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PART II. SUBSTANTIATION of the AXIOMSPROPOSED in the PART I

AXIOM 4(1) STRUCTURE OF ECOSYSTEM STABILITY

There exist the great variety of types of plant formations – ecosystems with definite composition of dominants. In fact, for only a part of the Palearctic province, the territory of the Former Soviet Union, it has been described 20 types of the formations, which include hundreds of the subtypes (Lavrenko and Sochava, 1956, 1956a). The information, useful for our aim, for most of them is scarce. Nevertheless, it is advisable to attempt to propose a characteristic of the main types with a view of SES, in other words, to give a sketch of their SESes.

In the present section, it will be shown composition of CESPPs peculiar for ecosystems concerning the main formations for variety of PPs, for which the data occured to be available. The totality of these CESPPs constitutes just SES of ecosystems of a given category. The below discourse is an attempt of holistic description of diversity of SESes. It will be offered CESPPs typical for a given formation, when it stays on the level ESPPs 3.1. "Proper control", and CESPPs of the level ESPPs 3.3. "Late control" for some groups herbivores, if ESPPs as to them stays continually on this level. It will be considered the following types of SESes peculiar for ecosystems depending on composition of their dominants.

4.1. Forests.4.1.1. Evergreen coniferous trees, Coniferales.4.1.2. Deciduous coniferous trees – the larch, Larix spp.4.1.3. Deciduous, Angiospermae trees. 4.2. Grasslands.4.2.1. Meadows.4.2.2. Steppes and prairies4.3. Deserts.4.4. Tundra.4.5. Forest-Tundra.4.6. Bogs.4.7. Fens.4.8. Marches.4.9. Riverain formations. 4.9.1. Brushwood on the sandy soil along rivers.4.9.2. Riverain forest.4.9.3. Riverain grassy formation.4.9.4. Reed seas.The types of SES 4.1.1, 4.1.2., and 4.1.3. concern forest ecosystems with great differentiation

of tissues within a tree and complicated structure. The components of the structure are as follows:

(a)The main story (stories) of dominants, i.e. matured trees. (b)Regrowth of dominants, i.e. young trees in the age range older than the seedling period,

but younger than maturity.(c)Seedlings of dominants(d)Seeds of dominants in the soil.(e)Undergrowth (a shrub stratum).(f) Ground grass cover.

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G.I. Vasechko STABILITY OF TERRESTRIAL ECOSYSTEMS TO PLANT PESTS: AN AXIOMATIC APPROACH.PART II. SUBSTANTIATION OF THE AXIOMS PROPOSED IN THE PART I

4.1. FORESTS4.1.1. Evergreen coniferous trees, Coniferales

The Scots pine, Pinus silvestris is convenient for understanding SES of the category 4.1.1. "Evergreen coniferous trees." This is so because this species has been studied well as to the problem of our interest. As a source of information, it is used the review by Yu. V. Sinadsky (1983) and other reports. If it needs, the data for other coniferous genera are used.

The list of invertebrate herbivores of Pinus silvestris according to Yu.V. Sinandsky (Ibid., p. 83) includes the following numbers of species: Acariformes - 10, Homoptera - 52, Aphididae - 33, Adelgidae - 5, Coccoidae - 9, Psyllidae - 1, Hemiptera - 21, Thysanoptera - 11, Coleoptera - 348, Lepidoptera - 78, Hymenoptera - 28, Diptera - 6, Orthoptera - 12, Blattoptera - 1, Isoptera - 3.

The group of vertebrate herbivores (Ibid., pp. 322-323) includes the elk, the deer, the bear, the squirrel, the stripped squirrel, the sable, eleven species of rodents, two species of the woodcocks, the wood-hen and twenty-three species of other birds.

The list of microflora (parasitic and saprophytic) includes 572 species, including 558 species of the fungi (Ibid., pp. 324-337). The phytonematodes are presented by 81 species (Ibid., pp. 320-322).

The vast number of the above species and affection by them all the living parts of pine trees suggests the wide diversity in traits of protection within a host-tree.

The data as to SES 4.1.1. are concerned to the W.C. Cook’s zone (b).

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.a. The main story of dominants

Needles, Defoliators

It should repeat the above data as to the protective role of oleoresin exudation against these defoliators of the families Lepidoptera and Hymenoptera. There are the data, in particular for Dendrolimus pini, that older larvae of the defoliators are able to feed by needles with significant oleoresin exudation. But for survivirship of neonate larvae, to find food with a lack of the exudation is of crucial importance. In healthy stands, this aim is achieved mainly by two means – usage of the part of needles with low exudation, and feeding staminate "flowers." Because in healthy stands such a resource is very limited, the defoliators are kept in them on the level Insignificant density continually.

In weakened pine stands, the defoliators tend to choose the part of needles with the less exudation. For example Neodiprion sertifer limits its feeding by needles of a previous year, although their nutrient quality is worst than that in needles of a current year. This species is rather tolerant to oleoresin. Moreover, it uses the oleoresin for self-protection against avian predators. At attacks of birds, the larvae feeding in-groups meet them vomiting droplets of oleoresin.

The needles in a lower part of tree crown have less rate of oleoresin exudation. That is why larvae of Lymantria monacha begin their feeding by needles in a lower part of crown on pine trees. The decreased protective response of host-trees is more important for survivorship than greater danger on the part of phytopathogens in shadow. Feeding by staminate "flowers" is also important for this species.

The third way to find food free from oleoresin exudation is used by the leaf-miner, Ocnetostoma friesei Sv. ssp. transbaicalensis Pozmogova. Its larvae feed by inner tissue of needles, but do not touch oleoresin ducts. If a larva breaks the duct, its mine fills by oleoresin, and a larva dies (Sinadsky, 1983, p. 108). Nevertheless, on healthy trees, oleoresin exudation pressure is so potent that a mine filled by oleoresin even if a duct is not broken.

Thus, pine ecosystems protect themselves against defoliators by CESPPs 2.1.1.2.1.2.1."Antibiosis to herbivores, Physiological (biochemical), Permanent."

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In firs, Abies spp., and spruce, Picea spp., defoliators (Choristoneura spp.) evade from oleoresin by means feeding in young instars by juvenile needles, where protective capacity has not developed yet. The needles ("fresh foliage") are free from oleoresin and are mild. Hatching in fall and hibernating in well-organized concealment, they wait appearing of fresh foliage. The rapid development gives them a possibility to finish their feeding before hardening of needles. The favorite host-tree for Choristoneura fumiferana is Abies balsamea, because "Balsam-fir foliage…not only appears at the proper time but remain green and succulent during entire the period of larval development" (Graham, 1939, p. 172).

"The black-spruce buds open too late to supply much food for the larvae at this critical period" (Ibid., p 171). "The white spruce, another host tree, produces abundant fresh foliage at the proper time, but its needles usually ripen up and become hard too quickly to permit full development feeding upon them" (Ibid., pp. 171-172). A probability of the outbreaks decreases at "…sufficient number of tree species and diversity of forest types" (Ibid., p. 174).

Thus, self-protection of Abies spp. and Picea spp. against defoliators is provided by CESPPs 2.1.1.2.1.2. "Antibiosis to herbivores, Physiological (biochemical)" with a cooperation with 2.1.2.1.1. "Superevasion from herbivores" and 2.1.2.4.2. "Heterogeneity of a species composition within a stock of dominants."

In winter, when favorite food is in a deficiency, some vertebrate animals feed by needles of evergreen coniferous trees, in particular the pines. This is known in the wood-cocks, Tetrao urogalus L. and T. parvirostris L., in wood-hen, Tetrastes bonasia L. They aggregate on some trees, and are able to strip them that leads to mortality of the trees (Sinadsky, 1983, p. 159).

In this case, it operates CESPPs 2.1.2.3.1. "Supertolerance to herbivores" of CESPPs 2.1.1.3.1.2. "Repair or compensation of losses of host-plant tissues" in a cooperation with CESPPs 2.2.2. "Natural enemies of vertebrate herbivores", 2.2.2.2. "Predators."

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.a. The main story of dominantsRoots, stems, branches, Herbivores

The most important herbivores of roots in ecosystems of coniferous tree species are white grubs – larvae of beetles of the family Scarabaeidae. In Eurasia, roots of Pinus silvestris are run the risk on the part of voracious white grubs of the cockchafer, Melolontha spp., and others, especially Polyphylla fullo L., Anoxia pilosa F., and Amphimallon solstitialis L.

Older roots of the pine have developed self-protection exerted by oleoresin exudation, which does no allow the grubs to feed them. Studies of Z.S. Golovyanko have shown that the grubs attempt to nibble the roots, but they are repelled by exuded oleoresin. Further, in any healthy stand of Pinus sylvestris, at least several large grubs of the cockchafer are present in the soil on the area of 1 sq. meter. Nevertheless, no signs of weakening of their host-trees are seen. Obviously, in such conditions, the grubs need to limit their feeding mainly by small roots of grassy plants (Z.S. Golovyanko, pers. comm.).

The role of CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent" for self-protection against the white grubs is seen clearly, if to compare the situation in pine biocenoses of the level ESPPs 3.1. "Proper control"and pine plantations (articenoses). In years with outbreaks of the grubs, at planting of the pine, it is necessary to protect roots of the seedlings with insecticides. This is so because rootlets of the seedlings are defenseless against the grubs. The plantations being overstocked in the stage of thicket (especially in 12-25 years) suffer due to severe competition for moisture and nutrients. Then, they often die off, because their roots are heavy affected by the grubs. In badly managed plantations, where weak oleoresin exudation in pine roots allows the grubs to survive, density of them is much more than that in biocenoses.

Stems and branches – this is a realm of CESPPs 2.1.1.1.1.3. "Nonpeference to herbivores, Of unknown nature" and 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent." These tree parts contain vitally important tissues of the conductive concern. Therefore, the traits directed on protection of them have reached maximal activity.

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Traces of Tolerance are seen in the situations, where a self-protection by Antibiosis is difficult to do. In the spruce, the butt part of stems is torn by the bear, Ursus spp. This is tolerable for trees, because a girdling is little of probable.

In the pine, upper shoots of matured trees are used by the pine shoot bark beetles Tomicus (Blastophagus) piniperda and T. minor for imaginal feeding and overwintering. The beetles penetrate in these thin twigs in summer in the period, when pines suffer due to moisture deficiency, which is most expressed in the tree parts most remote from roots. This results in a decrease of oleoresin exudation. Nevertheless, on the level ESPPs 3.1."Proper control", amount of beetle’s population too small to bring serious damage. There are observations that these beetles avoid the tree-tops with significant oleoresin exudation.


Shoots, Pine shoot mothsUpper shoots of young pine trees are affected often by several species of the pine shoot moth,

Rhyacionia (Evetria, Petrova) spp. This is a simple case: host-trees are protected by CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent." Intensive oleoresin exudation provides reliable protection against these herbivores. Other characteristics of the oleoresin (rate of crystallization, toxicity of its components) also are able to exert a protective effect. In Pinus pallasina, thick cover of buds serves as means of protection that does not allow neonate larvae of the moths to penetrate into living tissue. Hence, in this case, it operates CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent." The advanced Antibiosis to herbivores, Physiological (biochemical), Permanent (2.1.1.2.1.2.1.) is also characteristic for P. pallasiana species.

4.1.1.Evergreen coniferous trees, Coniferales4.1.1.a. The main story of dominants

Rootlets

Rootlets (roots of current season or of preceding one) are protected by CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" in cooperation with 2.2.1. "Natural enemies of invertebrate herbivores." Trees, however, are able to tolerate losses of their rootlets if these losses are not too heavy. This takes place on the level ESPPs 3.1."Proper control", where the grubs have alternative food (roots of diverse plant species), and numerous natural enemies, including bird and mammal predators, parasites and pathogens are active.


Staminate "flowers", Chewing herbivores

Staminate "flowers" are favorable foodstuff for defoliators. As to Choristoneura fumiferana, "In spring, staminate flowers provide succulent food for the newly emerged larvae… Larval development is promoted when staminate flowers fed on" (Greenbank, 1963, p. 218).

The same is true for Porthetria monacha. The abundance of the "flowers" and terms of their appearance vary from season to season. The coincidence of hatching of the larvae with abundant appearing of the "flowers" is important factor promoting growth of moth’s density (Khanislamov and Latyshev, 1962).

It is known specialized feeders of staminate flowers. Among them, the beetle, Rhinomacer attelaboides F. (the family Rhinomaceridae) has been reported (Sinadsky, 1983, p. 311). Further, larvae of Xyela iulii Brèb. (Hymenoptera: Xyelidae) "inhabit male "flowers" of the pine and feed by unripe pollen" (Ermolenko, 1974, p. 416).

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There are no reports about factors of Antibiosis in staminate "flowers", whereas they are obviously rich with proteins.

It is little of probable that significant part of contained in them pollen is consumed by herbivores. This is so because the term of producing of pollen is short, and the amount of it is very large. In fact, Pinus sibirica produces up to 130 kg of the pollen per hectare per year (Sinadsky, 1983, p. 12).

In the considering case, it operates CESPPs 2.1.2.3.1. "Supertolerance to herbivores, Compensation of losses of plant regeneration" and CESPPs 2.1.2.1.1. "Superevasion from herbivores."


Seeds, Herbivores

The cones are oleoresinferous. Often, oleoresin flows off cones affected by insects. Nevertheless, percentage of consumed seeds in the years with low yield of them is high. This suggests that seed-consuming insects are able to protect themselves against oleoresin. Neonate larvae of the insects feed by young cones (strobiles), where content of oleoresin is very low, if any. The older larvae are probably tolerant to oleoresin. This product serves as a means of protection of unripe seeds against vertebrate consumers.

As it has been shown above, due to periodicity of yielding, percentage of consumption of seeds of coniferous tree species is low, whereas vertebrate animals consume high percentage of seeds every year. Thus, for example, in years with low yield, they throw down from spruce trees 40-60% of cones, and in seasons with the abundant yield –30-40% of them (Glasov, 1984). The most part of seeds in the thrown down cones is eaten by the animals.

The seeds of Pinus sibirica (nuts) are eaten willingly by numerous species of mammals and birds. Usually, they consume 95% of the yield (Sinadsky, 1983, p. 158). In the same time, they are seeders of this species. The less (non-consumed) part of the harvest is sufficient for successful regeneration of Pinus sibirica. Its seedlings appear in abundance under canopy of this species or others. The main enemy of the regeneration is ground forest fires, rather than seed-consuming herbivores.

More detailed information as to the vertebrate herbivores is offered by D.V. Vladyshevsky (1984). Seeds of the spruce, the fir, and the larch fall out from cones on a soil surface in fall. During the fall and next winter, nearly 90% of them are consumed by rodents. In the pine, seeds fall out in winter at onset of frost after a thaw, when a frozen snow-crust appears. They are spread by the wind on large distance on a surface of the crust, and suffer a little due to rodents. Nevertheless, up to 84% of them are consumed by woodpeckers in cones before the fall out. Despite of such significant losses, the number of seeds is sufficient for forest regeneration, and its success is determined by the factors, which are not connected with the consumers.

Thus, seeds of coniferous tree species are protected by CESPPs 2.1.2.3.1.1. "Supertolerance to herbivores, Compensation of losses of plant regeneration" and CESPPs 2.1.2.2.1.1. "Disappearance from herbivores, Suppression of herbivores by means of food deficiency."


Needles, shoots, stems and roots, Sap-sucking arthropods, non-gall formers

This group includes organisms of various taxa of two classes. The grounds for such unifying consist in suggestion that they have a number of common traits in counteracting with self-protection of their host-plants and natural enemies.

The group includes the class Insecta with the superfamilies Aphididae (the aphids) and Adelgidae (the chermeses or adelgids), the suborder Coccidae (the scale insects), the order Thysanoptera (the thrips); the class Arachnidae – the mites, Acariformes.

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In this section, it will be considered the species, which do not produce special structures on their host-plants – galls. The species – gall-makers stay in different interrelations with their host-plants.

Having the mouthparts in the form of a minute beak, they pierce plant tissues and suck juices thereupon. This is a very precise feeding "mechanism", which allows them to evade the structures containing plant protecting substances. In coniferous species, the substances are oleoresins. Therefore, the interrelations of organisms of this group with their host-trees differ principally from those in the defoliators. The latter at feeding are forced to contact with oleoresin containing in host-plant tissues. That is why in healthy trees, the tissues protected by oleoresin are free from defoliators. Contrary, the sap-sucking arthropods, particularly the aphids "... are so generally distributed that it is scarcely possible to find a tree of sapling size or larger which is not infested by them to a greater or less degree" (Graham, 1939, p. 305). The mites may be found on any plant; as herbivores, they are omnipresent likely to microorganisms (A.M. Voytenko, pers. comm.).

Yu.V. Sinadsky (1983, p. 317-320) has given the list of sap-sucking species of this group inhabiting on pines. The list includes dozens of species. These species are fed by all the living tree parts from roots to tips.

CESPPs 2.1. "Plant resistance to PPs" operating against the groups are diverse. This becomes clear if to compare pine species growing in the same area (a botanical garden), but evolved as species in diverse environmental conditions. Such data were provided by N.N. Kuznetsov (1968, pp. 10-11) for the scale insects, Coccidae on pine needles. They were present on the needles, but stayed on Low density in the following situations:

i) Thick layer of cuticula (on Pinus pinaster and P. gerardiana).ii) Hypodermal cells stretched out in radial direction (on Pinus bungeana, P. gerardiana,

P. edulus, P. pinaster, and P. cembroides).iii) Thickened infradermal scleronchyma (on Pinus banksiana, P. pinaster, P. ponderosa, and

P. seopularum).iv) Many needles in a bunch, every needle of three-facet form or two-facet convex form (on

Pinus excelsa, P. monticola, P. strobus and P. pumila). v) A sing needle as a trait (on Pinus mesophylla).vi) The large number of oleoresin ducts that leads to often breakage of them at feeding by the

coccids (on Pinus pinaster, P. maritima, P. halepensis, and P. pityusa).vii)Disposition of oleoresin ducts close to a flat facet of a needle (on Pinus halepensis,

P. resinosa and P. pityusa).Furthermore, it was recorded a phenomenon, which might be considered as an evasion of

pines from affection by the coccids (Ibid., p. 11). Young needles of Pinus cembroides, P. edulus and P. gerardiana were free from coccids, because the young needles were divided in a bunch in the late term (September-October), when larvae of the coccids finished their hatching. In other pine species, the dividing of young needles took place in the period of coccid activity.

The above data suggest an operation of CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent" and CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent" as well as CESPPs 2.1.1.4.1. "Evasion from herbivores."

The study of the role of content of terpenoids in foliage of Tsuga species was conducted by M.S. McClure and J.D. Hare (1984). Density of Eiorinia externa Ferris and Nueulasis tsugae Marlatt (Hemiptera: Diaspididae) was studied on two species of host-trees. It was recorded the direct dependence of density one coccid species on content of some terpenoids, and the inverse dependence for another coccid species. Within a single Tsuga species, any trends did not exist. This fact and wide polyphagy of the coccid species, which infest in the USA forty-two species of coniferous species of seven genera, suggest that content of terpenoids is not a significant factor of the resistance. This report implies an operation of CESPPs other than the above.

The sap-sucking arthropods suffer on the part of predators and parasites. The situation, when native natural enemies are insufficiently effective for suppression on exotic species might be illustrated by the pine bark adelgid, Pineus strobi Hart. on the Weymouth pine, Pinus strobus in

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East Europe. "There are known the cases, when 30-50 old trees affected by the adelgid die off during four or five years" (Dmitriev, 1973, p. 218). This species is active both in parks and forest stands, i.e. actually in biocenoses. It invaded in Europe in XVIII century with seedlings of its host-trees. In East Europe, the Weymouth pine began to cultivate only in XX century. Native natural enemies have had little of time to adapt on this species.

Contrary, the experience of introducing of predators has shown that they are able to suppress density of their preys (an exotic species) to the level nearly Zero. Due to activity of natural enemies, in biocenoses, these organisms are common, but their density can hardly able to exceed a threshold of damage for dominants, except, when a species has invaded. Obviously, CESPPs 2.1.1.3.1.1. "Tolerance to herbivores, Deactivation of arthropod digestive juices" operates widely and cooperates with CESPPs 2.2.1. "Natural enemies of invertebrate herbivores."

Moreover, the interrelations of them with host-plants might be nearly symbiotic ones. This is evidenced by the role of honeydew as an imaginal food for parasites of herbivores and a stimulator of activity of nitrogen fixing organisms in the soil. In the conditions, where activity of natural enemies is insufficient, it develops protective traits, as it has shown above in the case with the pines. These traits belong mainly to the category of Structural Antibiosis. It is more durable than one of the physiological (biochemical) category. The latter can be overcome by these herbivores. The cause consists in high intensity of the microevolutionary process in this group comparing to other groups of herbivores. Two or three seasons are considered to be sufficient for adaptation of an aphid species to a non-host species of plants (Shaposhnikov, 1967; Eastop, 1972).

The advanced capacity of sap-sucking arthropods to adaptation results in often increases of their density in ecosystems, which as to others PPs stay on the level 3.1. "Proper control." In such cases, CESPPs 2.5. "Effects of crowding" enters into operation.

When density of sap-sucking arthropods becomes High, it takes place a protective response of host-plants. As to the balsam woolly aphid, Adelges piceae, "During the course of an infestation, the ability of a tree to support a population diminishes…Tree resistance apparently results from the nutritional quality of the stem deteriorating during attack and from production of a secondary periderm which prevent the aphid from inserting its stylets in the parenchyma below" (Greenbank, 1970, p. 564).

In this case, it operates CESPPs 2.5.1."Deterioration and/or shortage of food" with the effects 2.5.1.2. "Raising of secondary structural antibiosis" and 2.5.1.2.1. "Exuding of protective substances on a surface of buds or developing of protective barriers in affected tissues", 2.5.1.2.1.1. "Starvation."


Needles and shoots, Sap-sucking arthropods, gall-forming species

On evergreen coniferous species (the spruces, the firs, the pines), insects of this group is known as the chermeses, the family Adelgidae, and as flies of family Cecidomyidae. Injecting their saliva into host-tree tissues, they cause development of the galls – orbicular structures reaching the size of a hazelnut or a cone-shaped structure of the same size. The galls appear on internodes of a previous season in twigs or on shoots of a current year. On the pines, galls are produced by swelling of needles. In hollows of the galls, a progeny develops having food and shelter. Due to inhabiting in the shelters, these insects are well protected against natural enemies. That is why they are equally abundant in biocenoses (forests) and in parks (articenoses).

This fact implies that resistance of host-trees plays an important role in suppression of these insects. It was noted that distribution of the galls differs significantly from evidences of activity in other groups of herbivores. The trees with abundant galls can be near by those host-trees, where they are absent. Moreover, within a tree, some branches are affected heavily, whereas others are free of them.

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G.V. Dmitriev (1965a) explained these facts by the necessity of a strict correspondence between biochemistry of host-tree tissues and that of saliva of the arthropods for a success of the gall forming. Due to their hereditary diversity, host-trees are unequal in suitability to provide of gall-forming arthropods with ability to activate the tissues to form galls. Even within a tree, it is possible the biochemical differences due to the bud mutations.

On several species of the pines, it was noted the gall-forming by the flies of the family Cecidomyidae. Again, a success of the gall forming is determined by hereditary peculiarities of host-trees (Lee et al., 1994).

The role of physiological state of host-plants as a prerequisite of CESPPs 2.1.1.2.1. "Antibiosis to herbivores" in self-protection of host-trees against the chermeses is seems to be the open issue. This suggestion is based, in particular, on the following conclusion: "…any cultural practices are unable to change significantly the character interactions host-trees with chermeses" (Dragan, 1997, p. 14). Although G.V. Dmitriev (1965) insisted on affection by the chermeses just weakened trees.

The level ESPPs 3.1. "Proper control" as to the gall forming arthropods is maintained by CESPPs 2.1.2.4.1. "Hereditary heterogeneity of a stock of host-plants" and 2.1.1.3.1.4. "Tolerance to gall forming arthropods."

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.a. The main story of dominantsOleoresinoferous tissues, Resinocols

It is known a number of insect species, which inhabit the media very close to mass of oleoresin. Some species even feed by oleoresin. The habits of such species are described by B.M. Mamaev (1971). For definition of this group, this scholar used the term "resinocols." Some of them use oleoresin as a protective cover. This is reported for the families Tortricidae and Pyralidae (Lepidoptera). They feed by living tissues with significant oleoresin exudation, but isolate themselves from exuding oleoresin with a layer of silk. Larval mines of Laspeyresia duplicana Zett. are surrounded by masses of exuded oleoresin (galipot). Nevertheless, the mines are bored on the edge with deteriorated tissues of spruce of fir stems – wounds or areas affected by fungal rots. The same is true for Laspeyresia zebeana Ratz. inhabiting stems of the larch. The pine shoot moth, Evetria (Petrova) resinella L. is characterized by masses of oleoresin of the shoots inhabiting by its larvae. Young larvae of this species develop in the period of decreased oleoresin exudation. The older larvae are to able isolate themselves against oleoresin, when its exudation becomes high, and it pours out on a surface of the shoots (Krushev, 1957, p. 90).

The European spruce beetle, Dendroctonus micans should be included into the category of resinocols. Its older larvae and adults are tolerant to oleoresin. Although its eggs and young larvae are sensitive to this product. Therefore, a decrease of host-tree Antibiosis is necessary for successful colonization of this species. Comparing with many other species of bark beetles, Dendroctonus micans are able to colonized parts of trees (obligatory living ones) with higher oleoresin exudation. At deficiency of the plots, where the exudation is nil or negligible, the beetles attack plots of trees less favorable for the brood, but they improve the media pushing out exuded oleoresin (Wichmann, 1967). When the exudation stops, the oviposition begins.

The level ESPPs 3.1. "Proper control" as to the resinocols is maintained by CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent." The role of natural enemies (CESPPs 2.2.1.) is insignificant. Although when Dendroctonus micans colonizes vast areas on stems of trees, where oleoresin exudation is absent, it suffers heavily due to predation by the woodpeckers. In this situation known in Georgia (Former Soviet Union), the beetle should not be considered as a resinocol.

The dipterous resinocols (Cheilosia morio Zett., Brachyops spp., Thomasinia spp., Stelechodiplosis magna Moehn. and others) do not touch living tissues. They inhabit in oleoresin and feed by it. Therefore, they are out of the field of ESPPs.

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Some species of the genus Thomasinia inhabit cones of coniferous trees. B.M. Mamaev (1971) considers them as the resinocols and seed-consumers. In this case, ESPPs 3.1."Proper control" is maintained by CESPPs 2.1.2.2.1. "Disappearance from herbivores."


Diverse parts of trees, Phytonematodes

Pathogenic phytonematodes found out in all the parts of tree, with exception of needles, and in mycorrhiza. Mortality of older trees was recorded in the case of affection by an invading species. An example of such a situation, it can serve Bursaphelenchus lignicolus Mamija in Japan. Because this invasion has not catastrophic character, only weakened trees or those having no genes of resistance occurred to be endangered.

The native species of phytonematodes also are able to depress trees. Such an effect on the part of Dolichodorus silvestris was recorded in Pinus strobus stands in West Virginia (Sinadsky, 1983, p. 233). Probably, this took place on weakened trees, or it was a result of arising of a virulent strain (the saltation).

The level ESPPs 3.1. "Proper control" to phytomenatodes is maintained by CESPPs 2.1.1.2. "Antibiosis" and CESPPs 2.1.2.4.1. "Hereditary heterogeneity of a stock of host-plants."


Tree crowns, Plant semi-parasites

Several species of plant species are known as semi-parasites on branches of the pines and spruces. They use host as source of nutrients and water, whereas assimilates produce themselves. Yu. V. Sinadsky (1983, p. 208) reported about three species of this group – Viscum austriacum Wiesb., Arcenthobium pusilum K., and A. americanum L. The significant damage has been noted on the part Viscum austriacum in the conditions, where host-plants are probably weakened – on forest edges and on slopes of southern exposition.

As usually, the affection of the semi-parasites is not resulted in mortality of trees. Their interrelations are close to co-existence. Mortality of affected brunches or dieback are rare events.

In this cases, it is probable an operation of CESPPs 2.1.1.3.2.2. "Tolerance to phytopathogens, Limited compatibility", and 2.1.2.4.1. "Hereditary heterogeneity of a stock of host-plants."


Diverse parts of trees, Phytopathogens

Needles of all the evergreen coniferous species have well expressed Antibiosis - CESPPs 2.1.1.2.2.1.1. "Antibiosis to phytopathogens, Structural, Permanent" and 2.1.1.2.2.2.1. "Antibiosis to phytopathogens, Physiological (biochemical), Permanent." Contrary to deciduous tree species, needles of evergreen coniferous tree species, when they are healthy, do not bear any signs of phytopathogens. Only in the conditions, which preclude normal activity of needles, they are affected by phytopathogens. The latter are actually saprophytic organisms.

In particular, this is common in a lower part of crowns in stands with closed canopy. Weakened trees lost their capacity to protect needles over the entire crown. Yu. V. Sinadsky (1983, p. 169) noted that at breakage of water regime of trees in unfavorable environmental conditions (pines of forest edges of southern exposition, on sloped under effect of the mighty winds, on dry hills or in boggy habitats), their needles are affected often by the needle-shedding

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disease, Lophodermium pinastry (Sch.) Chev. (Leptostroma pinastry Desm.). This species is common in parks on old spruce needles at weather situation favorable for its development.

Stem-affecting phytopathogens are common in healthy stands on some living trees, which undergo gradual weakening. In subsequent years, they will die as the annual stem fall – a few percentage of trees, which loss their vitality due to competition or old age. In stands with closed canopy, the normal is slow dying of lower branches, because assimilation is impossible in shade. These branches are decayed being effected by phytopathogens.

The self-protection by CESPPs 2.1.1.2.2.1. and CESPPs 2.1.1.2.2.2."Antibiosis to phytopathogens, Structural and Physiological (biochemical)" spreads on above ground parts of trees, including staminate "flowers."

As to roots, healthy trees in their interrelations with the pine root rot, Fomes annosus Fr. (Heterobasidion annosum Bref.) and the honey mushroom, Armillariella mellea (Fr.) Karst. are in the range of CESPPs 2.1.1.3.2. "Tolerance to phytopathogens." Here, it operates the subcategories 2.1.1.3.2.3. "Demarcation of infested tissues" or 2.1.1.3.2.1.1."Symbiosis with former pathogens, Compatibility."

In stressed ecosystems, the situation is quite different. Affection of dominants with Fomes annosus or Armillariella mellea grows steadfastly.

It is known the cases, when trees are affected by a phytopathogen and die independently on their physiological state. Neither Antibiosis, nor Tolerance does operate in such cases. This is possible at invasion of foreign agent of infection or at arising of high-virulent biotype of native species (the saltation). The latter is characteristic for the rust fungi, whose microevolution is intensive. As an example of such a disease might serve Cronartium ribicola (Lasch.) Fisch. v. Waldh., which affect Pinus strobus.

Species of host-trees survive at appearing of such aggressive diseases by operation of CESPPs 2.1.2.4.1. "Hereditary heterogeneity of a stock of host-plants."

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.b. Regrowth of dominants

Vertebtate herbivores

Regrowth of dominants is a part of vegetation of an ecosystem, which will become dominants, when reaching of age of maturity. In Europe, in evergreen coniferous trees, it is adopted usually that trees enter in the category of maturity, when they reach 80 years. V.G. Nesterov (1949, p. 210) has supposed that the stage of regrowth begins with two-year age of trees.

The less age of trees, the more they exposed to grazing by hoofed animals. Now, destruction of the regrowth is a serious problem in silviculture. Because predators of hoofed animals are nearly wiped out even in reserves, density of these herbivores exceeds in many times that it takes place in undisturbed ecosystems. The problem of suppression of forest regeneration in reserves in USSR has been discussed in a number of publications, in particular by V.G. Mishnyov (1970) for the Crimea Peninsula (Ukraine). Density of the deer, Cervus elaphus G. in the Crimean Natural Reserve is as twice and half more than that tolerable for successful forest regeneration.

In exploiting forest stands, the predators of hoofed animals are actually absent, whereas hunting is organized badly, so that density of the elk, Alces alus L. reaches nine animals per thousand hectares of a forest area, whereas two or three animals of this species per this area are supposed to be normal (Smirnov, 1984). The High density results in heavy damage of forest regeneration. It is reported about affection of 23% of the best trees of the spruce Picea excelsa (abies) per plot, whereas 10% of them were killed over four years. The damage was recorded in trees of 20-80 years old. The trees younger 20 years were not mentioned. It seems, they occurred to be out of the observation, because were destroyd by the elks completely. "The bark of stems with diameter 12- 16 cm is damaged most often" (Ibid., p. 163.).

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Bark of butt parts of coniferous trees is torn by the bear, Ursus spp. The beasts use trees as a source of vitamins in spring licking a sap exuding from the wounds. V.I. Grimal’s’ky (pers. comm.) observed in the Carpathians Mountains damage of the spruce by Ursus arctos L. Mainly, the middle-aged trees with smooth bark on butts were suffered. The wounds did not engird all the circumference of the trees, so that they survived. The percentage of damaged trees was low, because density of the bear reached only a beast per several square miles. The damage was observed in very lonely areas.

The level ESPPs 3.1. "Proper control" of regrowth of dominants of evergreen coniferous trees as to hoofed animals in undisturbed ecosystems is maintained by a cooperation of CESPPs 2.1.2.3.1. "Supertolerance to herbivores" and 2.2.2. "Natural enemies of vertebrate herbivores", 2.2.2.2. "Predators."

In the case of wounding by the bear, it operates CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

In the Carpathians Mountains, it is common a damage of smooth bark of young spruce trees by the dormous, Glis glis L. The bark is eathen usually by paints with area up to 1 dm. The wounded trees do not die, but the damage promotes to affection by stem rots.

I.T. Sokur (1974) supposed that feeding by the bark is forced, when low yielding of favorite food of the dormouse – nuts of the beech, the hasel, the wahlnut, and fruits. In such cases, the dormouse migrates in spruce stands. Thus, spruce stems are protected against the dormouse by CESPPs 2.1.1.2.1. "Antibiosis to herbivores", CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", and CESPPs 2.2.2. "Natural enemies of vertebrate herbivores."


Defoliators

At outbreaks of defoliators, it is affected both the dominants in upper story and their regrowth. The defoliation of regrowth is common after complete consumption of food resource in the upper story, i.e. at a decline of an outbreak. This is so because defoliators evade shadow. At this phase of an outbreak, nutrients provided by insect’s excrements enrich the soil in an affected ecosystem. The regrowth obtains a resource for an operation of Tolerance. Probably, this is a cause of less sensitiveness of young trees to losses of their needle comparing with that in trees of an upper story of forest. At outbreaks, it survives greater percentage of young trees than older ones (McCarthly, 1981, P.M. Rafes, pers comm.).

In this case, again it operates CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."


Stem borers affecting young trees

When an ecosystem undergoes the aged crash, actually all the dominants in the upper story die being attacked by bark beetles. This phenomenon was recorded at the studies of outbreaks of the mountain pine beetle, Dendroctonus ponderosae in stands of the lodgepole pine, Pinus contorta var. latifolia (Amman, 1976, 1977; Berryman, 1976; Cole, 1976; Cole et al., 1976). However, a regrowth of this species survived and grew in dominants. After the period of 20 – 40 years, the crash returned.

The cause of survivorship of the regrowth have been seen in less thickness of its phloem, which is insufficient for development of bark beetle’s brood.

There are no reports about attempts to attack the regrowth on the part of Dendroctonus ponderosae. It seems, in this case, it operates CESPPs 2.1.1.1.1.3. "Nonpreference to herbivores Of unknown nature."

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In the regrowth, trees weaken due to own annual stem fall and weak insolation. They are colonized by the guilds of stem borers, which have some differences from those colonizing matured trees. There are a number of species of bark beetles with tiny bodies colonizing trees with thin bark or twigs of matured trees and young ones, for example beetles of the genus Pytiogenes. Also, in shade, it presents numerous species of “secondary” bark beetles (Drycoetes spp. and others). In these conditions, it operates again CESPPs 2.1.1.1.1.3. "Nonpreference to herbivores Of unknown nature" and 2.1.1.2.1.2.1."Antibiosis to herbivores, Physiological (biochemical), Permanent."

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.c. Seedlings of dominants

Herbivores

In pine nurseries, it is practiced sometimes a mowing of seedling that stimulates their ramifying. This implies that they being bitten out by vertebrate herbivores are able to restore their tissues. This is an operation CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues losses."

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.c. Seedlings of dominants

Phytopathogens

When growing of pine seedling in nurseries, it is necessary to protect them against the needle-shedding disease, Lophodermium pinastry and numerous species of root rots, Fusarium, Rhizoctonia, Pythium, Alternaria, Polyspora, Botrytis cinerea and others (Grimal’s’ky and Zelle, 1959). In the natural environment, the self-protection against the needle-shedding disease is exerted by CESPPs 2.1.1.2.2. "Antibiosis to phytopathogens", whereas against the root-rots by 2.1.1.3.2. "Tolerance to phytopathogens."

4.1.1. Evergreen coniferous trees, Coniferales4.1.1.d. Seeds of dominants in the soil

Herbivores and Phytopathogens

In the soil, seeds keep vitality over decades or even centuries. Here, they endangered by rodents and phytopathogens.

In the given case, it operates CESPPs 2.1.2.3.1.1. "Supertolerance to herbivores, Compensation of losses of plant regeneration" and 2.1.1.2.2. "Antibiosis to phytopathogens."

4.1.2. Deciduous coniferous trees – the larch, Larix spp.4.1.2.a. The main story of dominants

Needles, Defoliators

The bulk of data testifies about non-operation of Antibiosis in needles of the larches as to defoliators. The most convincing argument for this suggestion is the population dynamics of the larch sawfly, Pristiphora (Lygaeonematis) erichsonii in North America described by F.C. Craighead (1942, p. 369). Until introducing from Europe parasites of the sawfly, it "practically wiped out larch as a commercial species in eastern states and Canada maintaining high density year after year by 1910." After introducing parasites from Europe, population dynamics of this species obtains a pattern characteristic for the Old World – non-lasting outbreaks interrupted by a prolonged innocuous phase. Then, the larch began to restore itself in North America.

In this case, it takes place a cooperation of CESPPs 2.2.1. "Natural enemies of herbivores" with 2.1.1.3.1.2."Tolerance to herbivores, Repair or compensation of losses of host-plant tissues"

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on the level ESPPs 3.1. "Proper control", and CESPPs 2.5. "Effects of crowding" again with CESPPs 2.1.1.3.1.2. on the level ESPPs 3.3. "Late control."

In Siberia, population dynamics of Dendrolimus sibiricus suggests in favor of 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" as the only subcategory of CESPPs 2.1. "Plant resistance to PPs" operating as self-protection against this species. The studies of N.G. Kolomiets (1968) in the area situated in south Siberia on a border with the Steppe biome (the Tuva Region) over eighteen years showed that arising and decline of three outbreaks of this species can be explained by fluctuation of activity of its natural enemies.

This ecosystems stay continually on the level ESPPs 3.3. “Late control”, where CESPPs 2.1.1.3.1.2. cooperates with CESPPs of the Intrinsic class 2.5. “Effects of crowding.” Their pattern is directly density-dependent, lately spasmodic.

This area has all the sings of the W.C. Cook’s zone (a), where climatic conditions always are favorable for maintenance of High density of Dendrolimus sibiricus.

In areas situated northern and on high elevation above sea level, the important role in maintenance of ESPPs of the level 3.1. "Proper control" for this species is played by CESPPs 2.3. "Routine weather suppression."

4.1.2. Deciduous coniferous trees – the larch, Larix spp.4.1.2.a. The main story of dominantsFlushing buds, needles, Herbivores

The well-studied population dynamics of the larch bud worm, Zeiraphera diniana demonstrates the maintenance of the level ESPPs 3.1. "Proper control" by a cooperation of CESPPs 2.1.2.1.1. "Superevasion from herbivores", 2.3. "Routine weather suppression", and 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."


Stems, braches, Stem borers

M.G. Khanislamov and Z.Sh. Yafaeva (1958) stated that the larch bark beetle, Ips subelongatus is able to colonize host-trees, Larix sibirica on condition that the rate of oleoresin exudation in stems of breath height is the lowest according to numeric scores proposed by P.A. Polozhentsev. These numeric scores are "0", when the surface of phloem after 72 hours after the testing wounding is free from oleoresin, and "1", when oleoresin exudes by smallest droplets. Contrary, in the stems with the numeric scores of oleoresin exudation "4" and "3", settled the bark beetles were killed by abundant masses of exuded oleoresin.

The content of turpentine in phloem of the larch increased at weakening of the trees. In phloem of Larix sibirica defoliated by Dendrolimus sibiricus and colonized by the buprestid beetle, Phaenops guttulata Gebl., the content became twice as much as (2.8-4.2 mg per gr of dry weight) comparing with the healthy trees (Isaev and Ryzhkova, 1968).

The composition of turpentine in larch trees in the context of colonization by Ips subelongatus had been thoroughly studied by A.S. Isaev and G.I. Girs (1975). The review these data by G.I. Vasechko, (1981) showed the lack of dependence of the turpentine composition on physiological state of larch trees.

These data suggest that CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent" serves as self-protection of the larch against stem borers as it is characteristic for evergreen coniferous species.

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Buds, shoots, needles, Gall-forming arthropods

The larches, Larix sibirica and L. dahurica Turcz. in the southern part of their range are affected often by the larch bud gall midge, Dasineura laricis F. Lw. (Diptera: Cecidomidae). The interrelations of this species with its host-trees are specific, and are called by the scholars as endoparasitic ones (Nikol’sky et al., 1983).

Firstly, it should pay attention on the fact that CESPPs 2.1.2.4.1. "Hereditary heterogeneity of a stock of host-plants" operates in this case. This suggestion is confirmed by the following quotation: "Healthy and affected trees grew in the same plot, i.e. in the same growing conditions. The affected trees before a time of the studies were intensively inhabited by the midge during five years (1973-1977). In crowns of the healthy trees, it was not found out neither the new galls, nor old ones during ten years preceding the study" (Ibid., p. 174).

Secondly, CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" plays the important role. In fact: "Average density of the midge on the affected trees was 40% of their buds. The measurement of a width of the stem yearly rings on the breast height did not show valid differences in values of the radial increment between the healthy and affected trees. Interestingly, the value of this index in the affected trees before a beginning of the mass affection by the midge was lower than that in the healthy trees, whereas after exploiting by the midge, it increased to the level of the healthy trees" (Ibid., pp. 174-175). Thus, the affection resulted in an increase of vitality of host-trees.

The explanation of this paradoxal finding consists in the following words: "In the annually infested trees, about 95% of buds can be destroyed. Such trees do not die, but sharply reduce their cone bearing" (Ibid., p. 184).

Thus, in the affected trees, the resources, which in the inaffected ones are used for seed production, are spent for maintenance of the parasite. Some part of these resources even promotes vitality of the trees. Because seed production is redundant, losses even most part of them due to the parasitization do not impede thriving larch species.

4.1.3. Deciduous, Angiospermae trees

The composition of CESPPs in ecosystems of deciduous Angiospermae trees will be considered on an example of the English oak, Quercus robur as most studied species.

The list of insect and mite herbivores, which feed by living and dying oak tissues, includes 850 species; within them 530 species consume green tissues of foliage, buds and young twigs (Dovnar-Zapol’sky, 1954, p. 805). The SES of the oak will be proposed on the base of groups included in this list.

4.1.3. Deciduous, Angiospermae trees4.1.3.a. The main story of dominants

Defoliators

The number of species that feed by flushing buds and leaves includes 240 species of the butterflies and sawflies, as well as 103 species of the beetles.

The literature suggests that in the conditions of temperate climate, which favorable for thriving of all the natural enemies - parasites, predators and pathogens, SES of oak ecosystems against the defoliators is composed by CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", CESPPs 2.1.2.1.1. "Superevasion from herbivores" operating in a cooperation with CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", and CESPPs 2.3. "Routine weather suppression." Hundreds of species of natural enemies operating jointly with diverse weather stressors are able to keep density of the defoliators on the values, which allow host-trees to thrive without expenditures of their resources for Antibiosis.

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The trait of Antibiosis, in particular monoterpene biosynthesis appears to be an energetically costly process (Croteau and Loomis, 1975). Therefore, in the environmental conditions, where such CESPPs as 2.2.1."Natural enemies of invertebrate herbivores" and/or CESPPs 2.3. "Routine weather suppression" are potent, it has evolved the traits of Tolerance to herbivores and/or Evasion (Superevasion) from herbivores.

Natural enemies are very effective even in the conditions of arid climate if forest articenoses have been established with usage of proper silvicultural practices. The author had a possibility to observe young forest plots (about 12 years) planted in south of the Steppe biome in Ukraine, where foliage of the oak was actually free from signs of feeding by defoliators. These plots had mixed composition of trees and shrubs, as well as luxuriant grass cover with abundant flowering. The thriving of grasses was due to good moistening this plot. It was situated near by an irrigative canal, so that water penetrated from it to the soil under the forest plot.

In the same area, but outside of effect of the moistening, oak plots of the similar age planted as a monoculture with insignificant grass cover due to arid conditions were affected heavily by several species of defoliators.

Nevertheless, the species of oak evolved in the conditions of arid climate, where activities of parasites and pathogens are low, have acquired the potent defenders against defoliators – the ants, which exist in symbiosis with the trees. The author observed such a case in shade trees on streets in the city Mdina on the Malta Island. Foliage of these evergreen oak trees was intact by herbivores, whereas the ants were common on the leaves.

The same principle of self-protection is known in a number of tree species in the conditions of tropic climate where activity of defoliators (invertebrate and vertebrate) is especially high.

Thus, in the above conditions, SES as to defoliators of the Angiospermae trees is specific one and consists of CESPPs 2.1.1.2.1.4. "Antibiosis to herbivores, Symbiosis with natural enemies of plant pests."

On base of the data presented in the present report, it is possinle to offer the composition of the main CESPPs suppressing defoliators of the deciduous Angiospermae tree species depending on belonging to the guilds and the W.C. Cook’s zone in the decreasing order of their role as follows:


The early-spring guildThe W.C. Cook’s zone (a)

CESPPs 2.1.2.1.1. "Superevasion from herbivores", CESPPs 2.3. "Routine weather suppression", CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."


The spring-summer guildThe W.C. Cook’s zone (a)

CESPPs 2.5. "Effects of crowding", and CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

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The spring-summer guildThe W.C. Cook’s zone (b)

CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."


The spring-summer guildThe W.C. Cook’s zone (c)

CESPPs 2.3. "Routine weather suppression", CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

4.1.3.a. The main story of dominantsThe spring-summer guildThe W.C. Cook’s zone (d)

CESPPs 2.3. "Routine weather suppression."


The summer-fall and fall-spring guildsThe W.C. Cook’s zone (b)

CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."


Buds, Invertebrate herbivores

The buds of all the species are protected against invertebrate herbivores (defoliators and sap-sucking arthropods) by CESPPs 2.1.1.2.1. "Antibiosis to herbivores." In some genera, in particular the oak, Quercus, the birch, Betula, it operates CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent." In other genera, in particular the poplars, the chestnut, Aesculus hippocastanum, in addition to CESPPs 2.1.1.2.1.1.1., it operates CESPPs 2.1.1.1.1.1. "Nonpreference to herbivores, Visual and tactile" and CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent."


Foliage, Sap-sucking arthropods

This group embraces thirty-eight species of the bugs (the order Hemiptera), fifty species of the order Homoptera, including thirty-three species of cicads, Cicadina, two species of the leaf fleas, Psyllodea, one species of the white wings, Aleirodidae, ten species of the aphids,

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Aphidodae, four species of the coccids, Coccodea, and nine species of the phytophagous mites, Acarina (Dovnar-Zapol’sky, 1954).

A.M. Voytenko (1970) found out in the Forests biome of Ukraine in mixed stands with dominance of the oak, Quercus robur eighteen species of phytophagous mites. They occurred on every tree, but did not exert damage to the main story of dominants. The same species were recorded on deciduous trees in settlements. Contrary to forest ecosystems, in settlements, their density often reached the level of damage. At lasting drought in summer, leaves of the trees bear the numerous mites, loss green color and fade. The damage is serious in parks and especially in shade trees on streets, where activity of natural enemies of the mites is insignificant. The scholar supposed that the suppression of the mites in forests is exerted by their natural enemies (A.M. Voytenko, pers. comm.).

The same is true for the aphids (V.A. Mamontova, pers. comm.).In biocenoses, the part of SES 4.1.3. concerned the considering group includes CESPPs

2.1.1.3.1.1. "Tolerance to herbivores, Deactivation of arthropod digestive juices", and CESPPs 2.2.1. "Natural enemies of invertebrate herbivores." In the condition of low activity of CESPPs 2.2.1., it is probably evolving of the traits of CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent."

In articenoses (orchards, parks, shade trees), CESPPs 2.1.1.3.1.1. cooperates with 2.5. “Effects of crowding.”


Foliage and buds, Gall-forming arthropods

This group includes twenty-seven species of Cynipidae, two species of Cecidomydae, two species of the mites.

A.S. Moravskaya (1971) offered data for the apple-formed oak galfly, Cynips (Diplolepis) folii (quercus-folii) L. This species is numerous on Quercus robur and four other species of the oak in the Forest-Steppe biome and the Caucasus. The affection of some trees is spectacular. Weight of branches with leaves bearing the galls exceeds weight of branches without the galls in 2.4-3.6 times. Oak trees with stem diameter 6-9 cm on breast hight under weight of the galls bend by their tops to the ground. The affection takes place on separate trees in any environmental conditions, so that the affection is determined by heredity of trees, rather than by their physiological state. The gallfly is suppressed by seven species of parasites (up to 55% of host insect mortality), and in fall by birds, mainly the titmice.

It is obvious an operation of CESPPs 2.1.1.3.1.4. "Tolerance to gall-forming arthropods" and CESPPs 2.1.2.4.1. "Hereditary heterogeneity of a stock of host-plants", and 2.2.1. "Natural enemies of invertebrate herbivores."

4.1.3. Deciduous, Angiospermae trees4.1.3.a. The main story of dominantsOak catkins, Arthropod herbivores

In this guild, it is known several species of leaf-rollers (Lepidoptera, Tortricidae), several species of the bugs, Hemiptera, several species of the beetles, Coleoptera, thirteen species of the gall-forming Cyniptera, and one species of the mites, Acarina (Dovnar-Zapol’sky, 1954).

In this SES, it is probable an operation of CESPPs 2.1.2.3.1. "Supertolerance to herbivores", and 2.2.1. "Natural enemies of invertebrate herbivores."

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Acorns

The fauna of pest arthropods on acorns in East Europe includes six species of weevils, Curculionidae, four species of butterflies of the genera Laspeyresia and Pamene, six species of the gall-forming Cynipidae, and one species of the mites, Acarina. The latter species was recorded as a consumer of acorn’s cups. Several species of the bugs and mites suck fruit stalks and young acorns.


Acorns, Chewing arthropod herbivores

The damage due to weevils and butterflies, whose larvae feed inside acorns, is usually significant – more 50% of an acorn yield. Z.S. Golovyanko (1950), and G.E. Korol’kova (1963) reported about the important role of insectivorous birds in suppression of these herbivores. The following birds were most active: Parus spp., Sitta europea L., Certhia familiaris L., Turdus spp., Muscicapa spp., Fringilla coelebs L.

R.I. Zemkova (1980) considered this problem in city’s parks. She agreed with the important role of birds in suppression of these herbivores, and paid attention on the fact that acorns were less damaged by all the seed-consuming arthropods in old parks. In them, species composition and age structure of the vegetation were close to those in natural ecosystems that was favorable for nestling of birds.

In this group, again, it is probable an operation of CESPPs 2.1.2.3.1. "Supertolerance to herbivores", and CESPPs 2.2.1. "Natural enemies of invertebrate herbivores."

As to operation of Antibiosis in seeds against herbivores, this phenomenon was recorded only concerning of exotic species of the oak. Thus, in parks of Kyiv, the species of the American origin the northern oak, Quercus borealis and the pin oak, Quercus palustris produced acorns free from seed-consuming insects (Zemkova, 1980). Although in North America, their acorns are affected by resident species of insect herbivores (Dorsey, 1967).


Acorns, Sap-Sucking arthropod herbivores

The sap-sucking and gall-forming arthropods on acorns are suppressed by the same CESPPs as those on foliage. They are CESPPs 2.1.1.3.1.1. "Tolerance to herbivores, Deactivation of arthropod digestive juices", and 2.2.1. "Natural enemies of invertebrate herbivores." In the condition of low activity of CESPPs 2.2.1., it is probably evolving of the traits of CESPPs 2.1.1.2.1.1. "Antibiosis to herbivores, Structural."


Acorns, Vertebrate herbivores

The jay, Garrulus glandurius L. is an active consumer of acorns. In fact, "…stomachs of the jay bagged in vicinity of Moscow from October to April usually on 80-100% are filled by pieces of acorns. Probably, over a winter the jay feeds mainly by acorns, which have been stored by it in fall" (Formozov et al., 1950, p. 101). Nevertheless, "The storing of acorns by the jay or rather a hiding of them in diverse places in forest litter, ant hills and cracks in stems obtained long ago a positive evaluation on the part of foresters as one of the main means of the natural spread of the oak. From this view, some part of acorn yield fed by the jay should not be considered as a

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harmful activity. In south forests, according to A.A. Silant’ev (1905), the jay feeds by walnuts. Probably, appearing of walnut trees on clear-cut areas and clearings is connected with the activity of the jay" (Ibid., p. 101).

In this case, it operates obviously CESPPs 2.1.2.3.1. "Supertolerance to herbivores." Further, acorns have the trait, which protect of them against excessive consumption of them

by the jay. This is a form of acorns and extremely smooth structure of their cover that result in often slipping out of them from paws of the birds (Kholodnyi, 1941). They have habits to gather acorns in paws and to fly with them in secluded places for feeding. In so doing, a part of acorns is lost by the birds.

M.G. Kholodnyi (1941) noted that the jay managed with nuts of the hazel, Corillus avelana L. the same as did with acorns, and it served as an important spreader of this species.

The above cases demonstrate an operation of CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent."


Stems and branches, Stem borers

The group of stem borers on the oak includes 106 species of the beetles, Coleoptera, ten species of the butterflies, Lepidoptera, and four species of the wasps, Hymenoptera.

Although experimental data concerning the protection response of the oak and other Angiospermae species are scarce, a lot of indirect data suggest that as in the case of the coniferous species, it operates CESPPs 2.1.1.1.1.3. "Nonpreference to herbivores, Of unknown nature", CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent", and CESPPs 2.2.1."Natural enemies of invertebrate herbivores, 2.2.1.2.1. "Predators" (especially the woodpeckers).


Foliage, Phytopathogens

On oak foliage, the powdery mildew, Microsphaera alphitoides dominates. In Europe, this species is an exotic one. It penetrated from America in 1907. Unlike to American species of the oak, most of European oaks do not have a distinct Antibiosis to it. The wide spread susceptibility of the latter to this phytopathogen might be explained by its relatively low virulence. Presence of its micelium on leaves does not destroy completely their function. Therefore, the trees are able tolerate it.

In this case, it operates CESPPs 2.1.1.3.2.4. "Tolerance to phytopathogens, Permissible susceptibility."

In American species of the oak, it operates CESPPs 2.1.1.2.2. "Antibiosis to phytopathogens." Among the European oak species, it occurs ones, which insignificantly affected by the mildew, in particular the cork oak, Quercus suber L. In its leaves, a thick epidermis protects against the mildew. This is a case of CESPPs 2.1.1.2.2.1." Antibiosis to phytopathogens, Structural.


Stems, branches, Phytopathogens

The stem-affecting (bracket) fungi are common on the oak and other deciduous tree species. It is accepted that these phytopathogens infest weakened trees – those growing in unfavorable environmental conditions, damaged by fire, wounded by people or animals. Overmatured trees, even growing in the optimal conditions and undamaged are also affected by the rots. Such

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affected trees contimue to be living over a number of decades. In them, wood rots are limited by a central part of stems (a hartwood), which have no vascular tissues, and therefore is not vitally important. The trees skimp their resources exposing the parts to infection.

In such situation, it is possible an operation of CESPPs 2.1.1.3.2.5. "Tolerance to phytopathogens, Permissible susceptibility" and CESPPs 2.1.1.3.2.3. "Tolerance to phytopathogens, Demarcation of affected tissues."


Roots, Phytopathogens

In self-protection against the honey fungus, Armillariella mellea, it operates CESPPs 2.1.1.3.2.3. "Tolerance to phytopathogens, Demarcation of infested tissues" or CESPPs 2.1.1.3.2.2.1."Tolerance to phytopathogens, Symbiosis with former pathogens, Compatibility."

4.1.3. Deciduous, Angiospermae trees4.1.3.b. Regrowth of dominants

Foliage, Insect herbivores

Young oak trees are endangered by numerous species of insect herbivores. The activity of them is clear in articenoses, where vital conditions for insect herbivores are much better then those under forest cover. Returning to D.P. Dovnar-Zapol’sky (1954), it should the list of pest insects in young oak plantations, as follows: twenty-four species of the coccids, thirty-five species of the bugs, nine species of the aphids, and one species of the cicadids. Beside the sap-sucking insects, in oak plantations beginning with several years old, it appears numerous species of defoliators.

In regrowth of oak dominants, activity of the above species is much less. Here, the potent impact is exerted by natural enemies abundant in biocenoses and in properly managed articenoses. In such situation, it is obvious an operation of CESPPs 2.2.1. "Natural enemies of invertebrate herbivores" and CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."


Crowns, stems, Vertebrate herbivores

G.V. Kuznetsov and G.L. Lozinov (1984) reported about comparative resistance of regrowth of several deciduous tree species to grazing by the elk. The ash, Fraxinus sp. had some signs of Antibiosis. Its twigs were damaged no more than on 10-14% that did not suppress vitality of these trees. The resistance allowed the ash to compete successfully with the oak or the elm, and to grow into an upper story of forest. In the same stands, a regrowth of the oak was killed or heavy damaged on 70%.

The above observations were done in the conditions of excessive density of the elk. In undisturbed ecosystems, where density of vertebrate herbivores is lowered by the predators, there are no problems with serious damage of regrowth of dominants.

The rowan-tree, Sorbus aucuparia L. keeps berries over winter, and its trees often are overthrown by big animals, which feed by the berries in winter. As an adaptation to such a damage, it might be considered the species’ trait of foliation of the roots, which occurred to be above the soil surface. When planting of the rowan-tree by top down, its roots foliate and keep direction to the soil. This trait is used for cultivation of the species as an ornamentl tree of a weeping form. This is a kind of 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

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In 4.1.3.b., it operates CESPPs 2.1.2.3.1. "Supertolerance to herbivores" in a cooperation with 2.2.2.1. "Natural enemies of vertebrate herbivores, Predators", 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", and 2.1.1.2.1. "Antibiosis to herbivores."


Stems, PhytopathogensIn disturbed by human activity ecosystems, the damage of regrowth of dominant, in

particular the oak, induces of affection of the trees with stem phytopathogens, especially the stem cancer in a result of grazing by cattle or wild hoofed animals (Rudnev et al., 1975). The affected trees continue to be leaving during decades, although their commercial quality becomes low.

In undisturbed ecosystems, it is probable similar affection by phytopathogens due to grazing by wild hoofed animals, but at much less degree. Self-protection of the regrowth in such cases is exerted by CESPPs 2.1.1.3.2.5. "Tolerance to phytopathogens, Permissible susceptibility", CESPPs 2.1.2.3."Supertolerance", and 2.2.2. “Natural enemies of vertebrate herbivores.”


PhytopathogensThe powdery mildew is common on oak seedings. It is probable an operation of CESPPs

2.1.1.3.2.4. "Tolerance to phytopathogens, Permissible susceptibility." The affection oak plantlets by the powdery mildew is often accompanied by mortality of such plantlets. It might be they were weakened before the affection. Here, CESPPs 2.1.1.3.2.4. does not operate.

4.1.3. Deciduous, Angiospermae trees4.1.3.c. Seedlings of dominants

Vertebrate herbivores

Oak seedlings are consumed by vertebrate animals. Due to significant stock of nutrients in acorns, oak seedlings are able to restore their overground part even at repeated biting by the animals. When oak seedlings grow in shade, their sprouts die off due to lack of light. Nevertheless, they can renew them over several years, and grow well if favorable light conditions appear.

In winter, the seedlings are protected from animals by snow cover. This might be considered as a kind of CESPPs 2.1.2.2.1. "Disappearance from herbivores." In addition, in 4.1.3c., it operates CESPPs 2.1.2.3.1. "Supertolerance to herbivores" in a cooperation with CESPPs 2.2.2.1. "Natural enemies of vertebrate herbivores, Predators", CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

4.1.3. Deciduous, Angiospermae trees4.1.3.d. Seeds of dominants, AcornsVertebrate herbivores on/in the soil

On a surface of the soil and being sown, acorns are a favorite food for rodents the wild boar, Sus scrofa L. The activity of the jay provides acorns by CESPPs 2.1.2.1.1.4."Superevasion from herbivores. Protection of vulnerable plant stages." Again, it operates CESPPs 2.1.2.3.1. "Supertolerance to herbivores" in a cooperation with CESPPs 2.2.2. "Natural enemies of vertebrate herbivores."

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4.1.1.e., 4.1.2.e., 4.1.3.e. Undergrowth (a shrub stratum)Herbivores, Hoofed animals

From the view of ESPPs, an undergrowth in forest ecosystems of the categories of 4.1., 4.2., and 4.3. has common features. They consist in broad participation of the species with well-developed traits of protection against hoofed animals. They are unpalatable to these herbivores due to diverse causes. Thus, the common juniper, Juniperus communis L. has thorny needles with high content of pungent turpentine. A number of species are actually not fed neither by wild animals, nor cattle, because they contain in their bark high concentration of substances of bitter or astringent taste. They are the elder, Sambucus nigra L. S. racemosa L., the high cranberry, Viburnum opulus L., the buckthorn, Ramnus cathartica L., the alder buckthorn, Frangula alnus Mill., the smoke tree, Cotinus coggygria Scop., the hazel-tree, Corylus avellana L., the prick-wood, Euonymus spp. There are many thorny species: the Siberian locust, Caragana arborescence Lam., the barberry, Berberis vulgaris L., numerous brushes and semi-brushes of the family Rosaceae: Rosa spp., Crataegus spp., Prunus spinosa L., P. stepposa Kotov., Rubus ideaus L., and R. caesius L. As the poisonous species, it is know the mezerum, Daphne mezerum L., Cytisus spp., Euonymus spp. Rhamnus cathartica L. Ledum palustre L. (the latter is common in humid habitats).

In all these cases, it operates CESPPs 2.1.1.2.1.1.1. Antibiosis to herbivores, Structural, Permanent" and 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent."

The rowan-tree, Sorbus aucuparia L. is a favorite species for grazing by the elk. However, the rowan-tree is very tolerant, so that the consumption up to 80% of annual height increment over ten years did not affect on productivity of the trees (Kuznetsov and Lozinov, 1984). In this case, it operates 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

4.1.1.f., 4.1.2.f., 4.1.3.f. Ground grass coverVertebrate herbivores

The ground grass cover (herbaceous undergrowth) in forest ecosystems is characterized by high participation of poisonous plants. M.E. Tkachenko et al. (1939, pp. 458-459) offered a list of poisonous for livestock forest grassy species, which included twenty items. In this list, there are common species, which often prevail in the cover, namely: Convallaria majalis L., Asarum europaeum L., Hypericum perforatum L., Paris quadrifolia L., Melampyrum nemorosum L., Dugitalis grandiflora Mill., Pirosa rotundifolia L., Veratrum lobelianum Bernh. and V. nigrum L., Vincetoxicum officinale L., five species of Anemone, three species of Stellaria.

This list does not embrace all the range of forest grasses dangerous for cattle. A.M. Vilner (1974) added to the list such species, as the belladonna, Atropa belladonna L., the aconite, Aconitum napellus Kar. Et Kir., the upland fern, Pteridium aquilinum Kuhn. and other ferns, the gold-caps, Caltha palustris L., Actea spicata L., Cimicifuga foetida L. In some regions, the participation of poisonous grasses is so high that veterinary prohibits grazing of cattle in forest.

Many plant species are unpalatable. Among them, there are all the Bryophyta, Lycopodiophyta, and Angiospermae with rigid leaves (Vaccinium vitis idaea L., V. uliginosum L., Vinca herbacea W.K.) or with acid leaves (Oxalis acetozella L., Rumex spp.), with smarting above ground parts (the nettle, Urtica urens L. and U. dioica L.).

As to the mosses, Bryophyta, they are disregarded by mammals in area with temperate climate due to high content of lignin and low content of nutrients (Prins, 1982).

The seasonal aspect is also significant. In early spring, it is abundant poisonous, bitter and spicy grasses –the pasqueflower, Pulsatilla patens L., Ranunculus spp., Anemone spp., Gagea spp., Equisetum spp., and Tussilago farfara L., Adonis vernalis L. (Lyubimenko and Vul’f, 1927). The expressed self-protection is explaned by increased demand of vertebrate herbivores for forage after acute winter deficiency.

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In the above cases, it is obvious an operation of CESPPs 2.1.1.2.1. "Antibiosis to herbivores" with the subcategories 2.1.1.2.1.2.1. "Physiological (biochemical), Permanent" and 2.1.1.2.1.1.1. "Structural, Permanent."

In forest ecosystems, there are wide spread the grassy plants with thin, long, firm, plane, slip leaves often sharp on their edges or with thin and rounded in diameter leaves. These plants are known in the genera Juncaceae, Carex and Cyperaceae. These traits allow to the leaves to slip out from an animal’s mouth at attempt to feed by the plants. In so doing, it is possible a cutting of mouth tissues in the animals. Therefore, they are forced to bite only apical part of the leaves with juvenile (unprotected) tissues. Such a damage is tolerable for the plants.

In this case, it operates again CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent." The role of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", and CESPPs 2.2.2. "Natural enemies of vertebrate herbivores" is a secondary one.

4.1.1.f., 4.1.2.f., 4.1.3.f. Ground grass coverInvertebrate herbivores

O.P. Kryshtal (1959, pp. 288-289) studied insect fauna of diverse ecosystems as sources of agricultural pests. In forests on the ground grass cover, it was found out 168 species known as such pests. Among them, there are Oscinella spp., Opomyza florum, Meromyza saltarix, Phorbia (Hylemia) coarctata. On the nettle, it is common Pyrausta nubilalis.

The occurrence of insect herbivores on plants in the forest grass cover can be considered on the base of the article by L.M. Nosova et al. (1984). In it, it was reported species composition and indices of damage of leaf surface in dominate species of grass cover in spruce, birch and pine forest plots of diverse types in the Moscow Region (Russia). These plant species are the following: Oxalis acetocella L., Carex pilosa Scop., Ranunculus cassubicus L., and the fern Dryopterus lanuolato-cristata (Hoffm.) Alston. On every of these plants, species composition of insects occurred to be rather rich – several tens of items. Approximately, one third of them were phytophagous, one third – microphytophagous (the mites), and the rest – used the diverse ways of feeding, including natural enemies of the herbivores. The phytophagous species embrace the weevils (the genera Apion, Sciaphilus, Omias, Scleropterus, Polydrosus, and Phyllobius), the chrysomelids (the genera Crepidodea and Liliocerus), the aphids (the genera Cinara, Macrosiphum), the cercopidids (the genera Aphrophora and Philaenus), the cicadids (the genus Cicadella), caterpillars (the order Lepidoptera) and pseudo caterpillars (the order Tenthredinidae). The leaves had traces of defoliation – up to 30% of leaf surface on the fern, and up to 20% of leaf surface on other species, as well as traces of sap-sucking. This study is probably concerned to the specialized insect herbivores.

The data for a species of wide polyphagy, the fir spanworm, Boarmia bistortata Goeze, have been offered by S.S. Prozorov (1955). The list of host-plants of this species includes 115 plant species (Ibid., pp. 99-107). Notably, the presence in a plant species the substances of protective concern against vertebrate herbivores does not protect against the spanworm. In fact, such poisonous or unpalatable for the vertebrate species as Veratrum album var. lobelianum Schmalh., Aconitum excelsum Rchd., Caltha palustris L., Oxalis acetosella L., and Vaccinium vitis idaea L. were more damaged than favorite for the vertebrate the willow, Salis alba L. "The upland fern is very little damaged. It is known only a few insect pests of this plant, in which the first place is occupied by Strongylogaster lineata Christ. On the shave-grasses and the lycopodiums, there are signs of damage by the spanworm. The very little damage is observed on the cereals" (Ibid., p. 99).

Even such a poisonous plant species as Atropa belladonna serves as a host-plants for insects, in particular for the monophagous chrysomelid beetle, Chrysolina porphirina (V.M. Broudiy, pers. comm.), Pachyprotasis antennata Kl. (Tenthredinidae) (Tryapitsin and Zholokhovtsev, 1981, p. 29) and Pegomya betae Curtis (Anthomyiidae) (Elberg, 1981, p. 189).

M.I. Neischtadt (1948, pp. 141-143, 334, 336) reported that some plants in forest grass cover are pollinated by hymenopterous wasps and flies. This was noted in Listera ovata R.Br., Neottia

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nidus avis Rich., Epipactis palustris Crantz., and Calluna vulgaris Salisb. (Erica vulgaris L.). Thus, there exists a symbiosis the plants with parasites of insect herbivores.

In the case of insect herbivores on forest ground cover, it is probable an operation of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" in a cooperation with CESPPs 2.2.1."Natural enemies of invertebrate herbivores."

As to the slugs and the snails, which are abundant on the soil surface in forest, it operates the same CESPPs, which have been mentioned above in the cases of vertebrate and invertebrate herbivores.

4.2. Grasslands4.2.1. Meadows

I.V. Larin (1964, p. 5) determines a meadow as an area of the Earth surface occupied by perennial grasses growing in the conditions of moderate moistening. The attribute "moderate" means less than in bogs and more than in prairie (steppe). The primary meadows are pertinent to flood plains on the terrain, where water at flooding stays during the term, which is non-compatible with vitality of tree vegetation. The secondary meadows arise in a result removing of forest by people in mesic habitats with the aim of establishing of pastures. Meadows exist in mountain areas on latitudes above the forest belt.

The level of moistening in meadows is optimal for vital activity of grasses. In the meadow soil, a characteristic content of water is maintained on the level 60-80% of the full saturation, whereas air content is 20-40% of soil hollow (Larin, 1964, p. 242). On the other hand, plants growing in humid habitats are endangered by deficiency of oxygen for roots due to excessive moisture of the soil. In arid climate, the plants are endangered by moisture deficiency inducing a fading. Optimal water regime allows meadow pastures to tolerate the greater number of exposition to grazing comparing with that in pastures in other biomes. In fact, pastures in forest biome (a meadow) are exposed to grazing three or four times per season, whereas pastures in the steppe or semi desert - two or three times, in the desert - one or two times (Ibid., p. 349).

4.2.1. MeadowsVertebrate herbivores

From the view of ESPPs, the above data give the ground to suggest a vast operation of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" in meadow ecosystems. In fact, the review of literature offered by B.D. Abaturov (1984) has showed that wild mammal herbivores annually consume up to 80% of biomass of a meadow ecosystem that does not disturb its general stability. Contrary, at badly managed grazing by cattle, such a loading is destructive of meadow ecosystem. When the cows consumed 75% of the biomass at a single grazing operation, the next operations on the same place were imperfect (Johnstone-Wallace and Kennedi, 1944).

The difference is explained by the unequal behavior of wild and domesticated animals at grazing. When feeding, wild animals move over an area of a pasture much quickly than domesticated animals do. They are provoked to the quick moving by a pursuit on the part of their predators, so that they return to an affected plant with high probability over a term, which allows to this plant to restore of lost tissues. The role of this factor is demonstrated by advantages of the proper pasture management, in which cattle is forced to move from a plot to a plot after certain time giving to grass a possibility to regrow after grazing.

This measure is called the portioned or normalized pasturing. In so doing, on a grassy area, it is framed a pen with portable fence, where cattle feed usually a day or several hours. After that, a pen is transferred to another place, and the cattle are drawn there. It is practiced consumption of 60-70% of biomass within a pen. Then, it is left intact on 15-25 days that allows restoring of a volume of the biomass. Returning of the cattle on the aftermath gives the animals a possibility to feed juvenile tissues of regrown grass that is favorite food. A practice of application of the

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normalized pasturing in diverse countries showed its advantages. In particular, productivity of a pasture increased twice as much comparing with traditional practice, and it is maintained year after year (Larin, 1974, pp. 351-382).

It might be interactions of cattle with grasses at the normalizing pasturing simulate forage habits of wild animals in nature. Then, it operates CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

In the case of wild animals in biocenoses, this CESPPs operates in a cooperation with CESPPs 2.2.2. "Natural enemies of vertebrate herbivores", 2.2.2.2. "Predators."

The second means of self-protection of grassy species is presented by the traits, which suggest an operation of CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent." These are poisonous plant species. These species are well known in grazing management. I.V. Larin (1984, p. 152-153) reported that "In USSR, among studied in the forage concern 4730 plant species, it was stated 378 undoubtedly poisonous species and 336 species as suspiciously poisonous. The two latter categories compose 15% of all the studied species. Intoxication of animals by these plants undoubtedly occurs very often… Most number of poisonous and suspiciously poisonous species was revealed in the following families: Ranunculaceae - 116, Euphorbiaceae - 70, Compositae - 43, Umbelliferae - 20, Solanaceae - 19, Polygonaceae - 6, Scrophulariaceae - 17, Liliaceae - 28, Equisetales - 9. In the families Solanaceae, Euphorbiaceae, and Equisetales, nearly all the species are poisonous… Poisonous substances are the following: most or significant part of alkaloids, glucosides, saponines, organic acids, lactones, toxalbumines, a part of essential oils, dye-stuffs, and oleoresins… The families Ranunculaceae, Papaveraceae, Leguminosae, Solanaceae, and Liliaceae are especially rich as to content of alkaloids. Poisonous glucosides are wide spread in the families Cruciferae, Rosaceae, Scrophulariaceae, they are known also in the family Gramineae. Saponines have been found out in Caryophyllaceae, Primulaceae, Liliaceae, Equisetales. Organic acids are contained in Lichenes, Filicales, Senecio, Euphorbiaceae and others. Essential oils are known in many species of Compositae, Umbelliferae, Ericaceae, and Coniferales, whereas oleoresins in the family Umbelliferae."

Hierochloe odorata (L.) Wahlb. (Graminaceae) contains cumarine, and it is not fed by cattle, (Zhukovsky, 1938, p. 384). At presence in a grass stock of Deschampsia caespitosa (L.) P.B., a meadow is unaccessible for grazing (Ibid., p. 561).

The third means of the self-protection is represented by the mat-grass, Nardus stricta L. This plant is not tall – 10-40 cm height. Its stalks are thin, slide, are free of knots, leaves are thin and clasped to the stalks, bunch of stalks is a cone-shaped. The roots are firmly held in the soil. All these traits are aimed to slide off the bunch from an animal’s mouth at grazing. This species is considered as a forage plant, but of low value (Bel’gard et al., 1984, pp. 314). In this case, it operates CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, Structural, Permanent."

Carlina acaulis L. – this a plant with developed thorns on a single flower clasped to the soil as well as on a rosette of clasped leaves. It is another example of CESPPs 2.1.1.2.1.1.1. This species is common on mountain pastures in Middle Europe.

CESPPs 2.1.2.5.1. "Parasitic antibiosis, Growth under protection of nonpreference and/or antibiosis of other plant species" operates also. The facts in favor of this suggestion are the following. The discourse uses the review by T.A. Rabotnov (1983, p. 57-58). In tests by J.L. Harper et al. (1961), Trifolium fragiferum L., being sown in pure stand, was eaten by the hare, whereas if this species was sown in a mixture with Trifolium repens L., both species were not eaten by the hare. Further, the cereals growing near by Ranunculus bulbosus L. are not eaten by livestock (Harper, 1977).

Thus, several CESPPs provide protection of meadow ecosystems against vertebrate herbivores – hoofed animals and hares. Although, CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" dominates. This fact might be explained by better competitive capacity of the species with this trait. In fact, all the couch-grasses, Agropyrum spp. are considered as good forage plants (Larin, 1974, pp. 67-69, 83-86). In the same time, these species are tiresome weeds in articenoses.

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This fact suggests advantages of the traits of Tolerance in competition with species protecting by Antibiosis. The latter, however, prevail in the conditions, where grazing becomes excessive, in particular around spring in mountain pastures. Here, it dominates unpalatable for cattle the sour-dock, Rumex spp.. On large areas of meadows in the Carpathians Mountains, the mat-grass Nardus stricta L. is a dominant. Such ecosystems arose in a result of digression of primary ecosystems at intensive grazing (Zhilyaev, 1984). In such conditions, a beneficial effect is exerted by wild boars, which break the mat-grass sod in search for soil-dwelling insects, so that other plant species are able to regenerate on spots of the bare soil.

4.2.1. MeadowsInvertebrate herbivores

The entomological literature abounds in reports about wild grassy vegetation as a source of pest insects of agricultural crops. In this context, it is valuable the reviews by A.Ph. Kryshtal (1947, 1959) and E.P. Narchuk (1987). They content great many data both original and literature, which allow to perceive the character of resistance of grassy plants against insect herbivores. This information concerns not only the Meadow ecosystems but also other grassy and even forest ecosystems. As to the latter, it is pertinent to the ground grass cover.

E.P. Narchuk (Ibid., p. 5) characterizes the fly superfamily Chloropoidea by the following words: "They are a mass group of flies in meadows, bogs, meadow-like steppes, savannas and other open habitats. They present in high density and in wide species diversity always on the cereals and the sedges. In USSR, all the associations with cereals as dominants of the total area 1500 thousand of square km of the natural (a climax of succession) and anthropic origin are inhabited by the flies. They are especially abundant in the mesophitic conditions. In Middle Europe on meadows, they constitute nearly a half of the entire number of species of fly herbivores (Bährmann, 1976, 1980). In fauna of USSR, it has been described 468 species of sixty-two genera of the flies. They are known from the coast of the Ice Ocean to mountains of Central Asia. In the tundra, their fauna is innumerous, mainly on the sedges. In the steppe zone, they tend to be numerous in mesic and hydric habitats. In the desert zone, they are common in the salt-soil habitats, and on the sedge in flood plains. The group includes the genera Oscinella, Chlorops, Meromyza, and Dicraeus with numerous pest species of cereal crops."

A.Ph. Kryshtal (1947) studied occurrence of cereal flies on seventy-one species of wild cereals and five species of cultivated ones in diverse biomes of Ukraine from Forest to Dry steppe ones. It was found out dozens species of the superfamilies Cecidomyidae and Chloropidae. In this book, it was reported about mass affection of the couch-grass, Agropyrum pectiniforme (cristatum) by the Hessian fly, Mayetiola destructor and other species of this genus (Ibid., p. 30), and affection of the couch (Devil’s) grass, Agropyrum repens on fields by diverse species of the frit fly, Oscinella (Oscinosoma) frit (Ibid., p. 54). In these weeds, the number of plants with affected stalks was greater than that in cultivated species – the wheat, the rye, and the barley.

A.Ph. Krystal (1959, p. 323) found out on secadol meadows 156 species of agricultural pest insects, on flood plane meadows – 165 species, on abandoned fields – 80 species.

When studing of the role of wild cereals in “meadow associations” as reservations of the frit fly, Oscinella frit L., it was obtained valuable information about the affection (Vasina, 1929). The frit fly occurred on all the studied species - Agropyrum repens P.B., Phleum pratense L., Agrostis alba L., Agrostis vulgaris With., Poa annua L., P. pratensis L., P. compressa L., Festuca rubra L., F. elatior L., Bromus sterilis L., Anthoxantum odoratum L., Alopecurus pratensis L., Dactylis glomerata L.

The most abundant species - Agropyrum repens had the greatest percentage of affected stems, and the value of affection depended on two factors – density of stems per quarter of 1 sq. meter in average, and the dates of the survey.

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Depending on the density, the numbers of affected stems per plot were the following: low density (347 stems) – 88.7; moderate density (735 stems) – 6.13; high density (918 stems) – 0.29.

Depending on the dates of the survey, the numbers of affected stems were the following: 11, May – 13.7%; 3, June – 2.9%; 15, June – 1.8%; 3, August – 8.9%; 24, August – 13.7%; 1, October – 7.6%.

These data demonstrate that value of the affection depends on abundance of young tillers in the host-plant. The tillers were abundant on the plots with sparse vegetation, and in May and August, when rains were common. It implies that density of the frit fly is suppressed by CESPPs 2.1.1.4.1. ''Evasion from herbivores.''

Further, domination of Agropyrum repens (from 36.6 to 74.5% of all the species stock in the diverse plots), despite it is a preferred host-plant to the frit fly suggests an operation of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

In addition in this study, it was found out at least ten other species of cereal flies, whose density had the same trend.

It is notable the following observation by A. Ph. Kryshtal (1959, p. 214): '' In 1946 at severe drought, on meadows in the flood plane of the Dnieper River near by Kaniv, a number species of grasses was affected en masse by the frit fly, Oscinella frit. The heaviest affection took place on Digraphis arundinacea, which grew on wet meadows and bogs. A special study showed that D. arundinacea was such affected, because young sprouts grew from its main stalk. The fly's females lay their eggs on the young sprouts.''

In the context with this observation, it was mentioned that Oscinella frit laid their egg on cereal crops mainly in early stage of their development – two or three leaves (Ibid., p. 214). Hence, presence of young sprouts is vitally important for survivorship of larvae of this species.

Spikes of Agropyrum repens are damaged by the fly Chlorops novaki (Kryshtal, 1959, p. 213). In grassy biocenoses, the spike beetles, Anisoplia spp. feed by spikes of the couch-grasses, Agropyrum spp. (Kapel’kin, 1923, pp. 51-52).

The aphids (seventeen species) are common on wild grasses in all the ecosystems, excluding dense forests (Ibid., pp.189-194). It is concerned, in particular, such pests species as Sitobion avenae, Schizaphis (Toxophera) graminum, Phopalosiphon padi, Rh. maydis, and Brachycolus noxius.

The beat webworm, Loxostega stricticalis L. consumes plants of thirty-five genera, especially weeds of the family Chenopodiaceae and many species of the mugwort, Artemisia spp. (Shchegolev et al., p. 358). Weeds and wild grasses serve as a source of affection of agricultural crops (Ibid., 1949, p. 364).

The corn stem moth, Pyrausta nubilalis Hb. in the USA consumes 230 plant species of forty genera. In USSR, it consumes forty-seven varieties of crops and 101 species of weeds. The favorite food – the common mugwort, Artemisia vulgaris L., and the hemp, Cannabis spp. (Ibid.,p. 368).

In spite of wild grasses maintain insect pests on significant density, vitality of these plants is not suppressed. Contrary, many of them are tiresome weeds. For example, cereals weeds, in particular the couch-grasses, Agropyrum spp., are indispensable host-plants for the Hessian fly, Mayetiola destructors in the period between harvesting and appearing of crops’ plantings. During this period, the fly has time to develop in two generations on this weed. Therefore, control of the weeds is considered as an important means of suppression of the fly (Ibid., 388).

The valuable results were obtained at the study of insect fauna of a meadow in the subalpine zone in the Carpathians Mountains (Tsarik and Kobyv, 1984). This was a plot of the ruderal vegetation on the altitude 1370 meters above sea level. In spite of wet and cool climate of this area that is not favorable for insects, their fauna on the resident dominant species sour-dock, Rumex alpicum occurred to be rich. It includes thirty-five species of insects of eighteen genera. Of them, herbivores species composed 38%, and predators – 50%. These herbivores consumed about 47% of the leaf surface and up to 20% of the roots.

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In this study, it is notably that a plant species having a distinct trait of Antibiosis to vertebrate herbivores has no the same trait as to insect herbivores. The cases cited above also suggest that plant species, which are unpalatable for cattle, serve as common or even favorite host-plants for insect herbivores.

The capacity of arthropods to adaptation to feed by plant species with trait of CESPPs 2.1.1.2.1.2. "Antibiosis to herbivores, Physiological biochemical" is much more than that in vertebrate herbivores. The selective pressure exerted by the arthropods results in developing of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", and 2.1.1.4.1. ''Evasion from herbivores'', which occur to be effective on condition that CESPPs 2.2.1."Natural enemies of invertebrate herbivores" operates well.

There are the data that in grass ecosystems, parasites of insect herbivores are very active. Because available data concerned mainly steppe ecosystems, this issue will be considered in the next section.

In vertebrates, there exist the cases of consumption by poisonous plants. However, these cases should consider as a quacking, rather than a feeding. Probably, in such a way, the animals are unloaded from helminthes. It is pertinent to recall the American name of the very toxic plant, Veratrum spp. – the bear garlic.

Consider situation in a grassy ground cover in fruit orchards. The orchards are common in mesic habitats close to meadows or in xeric (steppe) ones, but in the latter case, it is used often irrigation. These facts give grounds to discuss in this Section some interrelations of grassy plants with the phytophagous mites. Because the plants serve as a source of affection of fruit trees by these pests, scholars collected valuable information about the question under study.

In fact, I.Z. Lifshits (1964, p. 18) has reported: "In spring, females of Tetranichus atlanticus McG. migrate from fruit trees on weeds. Here, they feed and reproduce intensively forming large colonies. When the food is exhausted or weeds become dry out in summer, they return on trees. In orchards, where bare furrow is practiced, density of T. atlanticus is insignificant, the mite occurs mainly near by shelterbelts. In orchards with abundant weeds, the mite is common."

A.M. Voytenko (1970, p. 98) has described the situation in following words: "The common spidery mite, Tetranichus telarius L. and the atlantic mite, T. atlanticus McG. reach high density in orchards with poor cultural practices, where weeds serve as a "bridge", on which the mites come to tree crowns. In so doing, the apple varieties with low or pendent crowns suffer especially severe. In orchard plots, which are free from weed, constant damage due to the mites is absent."

These facts show that density of the mites on weeds is usually significant. Nevertheless, the weeds thrive. This suggests an operation in grassy plants CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" as a means of self-protection against phytophagous mites.

Thus, in meadow ecosystems, ESPPs to diverse group of arthropod herbivores is maintained by an operation of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" in a cooperation with 2.1.1.4.1. ''Evasion from herbivores.''

It has been known that grassy agricultural crops produce biomass, whose vitality cannot be maintained further due to deficiency of vital resourses, especially in the conditions of competition within a plant stock. This (redundant) part of plant's biomass dies off independently on affection of it by herbivores. Therefore, consumption of this part of plant's biomass is indifferent to vitality of a plant. This phenomenon is considered as an operation of CESPPs of the category 2.1.1.3.1.3. ''Tolerance to herbivores, Indifference to losses of host-plant tissues.'' Obviously, in the meadow ecosystems, where competition within a plant stock is very intensive, an operation of this CESPPs is common.

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4.2.1. MeadowsPhytopathogens

The data on interrelations between meadow grasses and phytopathogence are scarse. The knowledge of those in agricultural crops suggests an operation of diverse subcategories of 2.1.1.3.2. '''Tolerance to phytopathogens'' and 2.1.1.2.2. ''Antibiosis to phytopathogens.''

4.2.2. Steppes and prairies

V.G. Mordkovich (1982) has been pointed out numerous definitions of this category of ecosystems, which, however, do not offer comprehensive characteristics of all diversity of them. From the view of ESPPs, it is important that they are ecosystems with grasses as dominants, which differ from the meadows by presence of the additional period of suppressed vital activity of their vegetation – deficiency of moisture within a season. Depending on climatic conditions, severity and duration of this period vary in the wide range. Its duration is from two months in north areas of the Steppe biome to half of year in its south part. Depending on traits of the period, this category of ecosystems is subdivided on several subcategories, namely: meadow-like steppes, true steppes, dry steppes and desert-like steppes or semi-deserts (Ibid., pp. 30-35). These characteristics determine composition of CESPPs in their ESPPs.

4.2.2. Steppes and prairiesVertebrate herbivores

It is appropriate to consider SES of the category 4.4.2. beginning with the soil-dwelling rodents. "The soil-dwelling rodents inhabit all the biomes… excluding the Polar desert biome. Their role is especially significant for vegetation of forest-less well drained areas (the biomes of Tundra, Meadow, Steppe, Prairie, and Semi-Desert)… they are most abundant in steppes and semi-deserts. "The virgin dry steppe and semi-desert are true realms on the rodents. Myriad burrows, thousands of subsoil galleries and tunnels …pierce the subsoil" (Formozov, 1954, pp. 309-310)" (Rabotnov, 1983, p. 53).

4.2.2. Steppes and prairiesVertebrate herbivores, Soil-dwelling rodents

In steppes of Eurasia, from ninety-two resident species of mammals, the rodents are represented by seventy-two species (Mordkovich, 1982, pp. 125-126).

Density of rodents in grassy ecosystems reaches often High values that implies the good adaptation of them to the environment of steppe ecosystems. Providing by food in them is achieved by wide polyphagy and capacity to store forage. In fact, it was showed that the vole, Lagurus lagurus Pall., the subfamilly Microtinae is able to feed by 107 species of steppe vegetation, including the lichens and the mugworts (Formozov, 1976). Fifty species of the rodents from seventy-two of ones inhabiting steppes of Eurasia store their food – seeds or hay (Mordkovich, 1982, p. 159). In them, it is common the trait of dormancy. In some species, the dormancy continues eight months. The dormancy allows limiting their activity by the period of flushing of vegetation.

A dwelling in burrows of a complicated construction provides them with rather good protection against weather stressors and predators. Developed responses allow them to save from predators outside of their burrows. The predators are able to decrease density of rodents, when the latter exhaust their food resource in vicinity of burrows, and therefore rodents need to move for food on large distance. This is a true problem for rodents. For the vole Lagurus lagurus, is characteristic to wipe out all the vegetation around its burrow at radius of six meters; then, it is forced to move to a new place (Ibid., p. 170). In undisturbed by people ecosystems, where predators were active, the moving led to mortality. Such mortality concerned CESPPs 2.5. "Effects of crowding" might be significant now only in natural reserves of large area.

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It is advisable to put a question: what kinds of factors precludes destroying of grassy ecosystems by the rodents? The factors concern CESPPs 2.5. "Effects of crowding", but an operation of its subcategories is determined by advance in adaptation of a species to the environment. In this respect, the difference among rodent species is substantial.

The difference was showed by B.D. Abaturov and G.V. Kuznetsov (1983) in the studies conducted in the desert-like steppe to the north from the Caspian Sea. The best adaptation was noted in the ground squirrels, Citellus spp. At deficiency of food, these animals fall in dormancy, which continues in dependence on availability of food (Ibid., p. 61). They consume up to 20% of grass biomass in seasons with normal moistening, and up to 38% of it at drought (Ibid., pp. 60, 64). The prolonged dormancy decreases weight of animals and their fecundity. Therefore, great fluctuations of density are not characteristic for them.

The above quoted scholars suggest that the best adaptation is characteristic for diverse species of the ground squirrels and marmots, Marmota spp., whereas the worse one - for the voles.

In fact, density of the vole, Microtus brandtii undergoes wide fluctuations. When all the food resource becomes exhausted, the population decreases to the Insignificant level of density that continues a number of seasons. During this period, the vegetation restores.

The character of population dynamics of rodents in grassy ecosystems and factors of the dynamics were considered by S.A. Severtsev (1941, pp. 175-184). This review allows understanding, what kinds of CESPPs operate in SES of steppes as to these herbivores. Here are the data for the voles, Lagurus lagurus Pall., and Microtus arvalis Pall. in steppe in south Ukraine. These species demonstrated the trend of 3-4 years growth of density.

Activity of natural enemies was as follows: at decline of density, it took place heavy mortality due to pathogens. In previous years, percentage of mortality was rather high, and the main cause of mortality was supposedly avian predators. In the first month of life of the first generation, the mortality equaled 27% per 10-day period, lately – 20%. Nevertheless, this mortality was unable to preclude significant growth of the density. "We observe huge difference in density of the mice between spring and fall" (Ibid., p. 179).

In late summer, when food was in shortage, growth of density occurred to be less, or even it decreased. In early spring, when snow melted, the mortality increased sharply. The cause was penetration of melting water in burrows, so that it appeared of ice plugs, which precluded entrances in the burrors. In this period, voles were defenceless to their predators. Nevertheless, the density grew year after year until on third or fourth year, the population underwent a decline being affected by pathogens.

A periodicicy of the outbreaks was expressed rather weakly. "If melting is quick, the mice can be nearly exterminated" (Ibid., p.178). In a result, the periodicity fails. Notably, population dynamics of the voles kept its uniformity within limited area. Thus, in 1913, density of voles burrows in the Razyan Region reached 12,000 pieces per hectare, whereas in near by Regions, it was about 200 pieces. In 1923, in diverse Disricts of the Voronezh Region, areas in hectares with High mice density were as follows: 47,250; 51,200; 11,890; 4,600; and 1,000 (Ibid., p. 183). The significant difference in weather situation among Districts within a Region is little of probable. This implies, that the population dynamics is deternined mainly intrapopulational factors – interrelations between the hosts and their pathogens.

The important factors, which take part in sharp decline of the ground rodent at High density, are parasites (helminthes, fleas, and mites). Dwelling in burrows and crowding make the conditions, in which these natural enemies thrive. The periodicity in population dynamics of a number species of the rodents in grassy ecosystems recorded by many scholars, is determined by the microevolutionary process of fluctuation of virulence of pathogens and parasites. The extreme expression of this process is arising of epidemics of mortal diseases as the plague.

Diseased animals are favorite food for predators. For example, S.S. Folitarek (1948, cited in N.P. Naumov, 1963, p. 485) compared the number of deseased individuals of the vole, Microtus arvalis in traps and as a prey of avian predators. In the preys, the number of the voles with

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parasitic helminthes, degeneration of a liver and a spleen was twice as more comparing with those in the traps reaching in some cases 68%.

I.Z. Klimchenko et al. (1986) on the base of fifty years studies showed dependence of plague epidemics on population dynamics of the rodents. The epidemics arise at the outbreak phase. They are promoted by often contacts diverse species of rodends with active role of the vectors, in particilar the fleas. In the past, the main source of the plague epidemics, it was the ground squirrel, Citellus fulvus. Later, in a result of ever-increasing of overgrazing, areas inhabiting by the ground squirrel decreased from twenty million hectares to five million ones. On the rest area, the main sourses of the plague epidemics became the sandy mice, in particular Gerbillus meridianus Pall. and G. tamaricinus Pall. This fact implies destruction of dry-steppe ecosystems in result of overgrazing that resulted in appearing large areas of sandy habitats.

The polyphagy of the rodents suggests that Antibiosis of above ground parts of grassy plants is not important as a means of their self-protection. Only the little number of steppe plants are ignored by the rodents, for example the Austrian wormwood, Artemisia austriaca Jacq. (Voronov, 1973, p. 238). Contrary, roots of grassy plants are protected well. In the roots, it is concentrated most part of biomass of the plants. The more expressed aridity of climate, the greater part of live biomass is deposited in roots. This part is as follows: in Ukraine – 91%, in Kazakhstan – 94%, in Khakassiya – 96% (Mordkovich, 1982, p. 57). I. K. Pachosky, the prominent phytocenologist, called the steppe as "the forest growing by its stems downwards" (Ibid., pp. 20-21). These words should understand that the roots of steppe grassy plants are well-protected.

In SES of 4.2.2. " Steppes and prairies " as to the soil-dwelling rodents, it operates CESPPs 2.5.1. "Deterioration and/or shortage of food", 2.5.1.3.2.2."Decrease of body weight and fecundity", 2.5.1.4. "Emigration in the adult stage in advance of food deterioration and/or exhaust" with final effect 2.5.1.4.1. "Mortality due to diverse factors", CESPPs 2.5.4. "Fluctuations of herbivore host resistance to pathogens and parasites as well as virulence of pathogens and aggressiveness of parasites" with the final effect 2.5.4.1. "Suppression of herbivores over the period, which provides a reprieve for restoring of vitality of dominants." In some species, it operates CESPPs 2.5.1.7. "Cannibalism" that resulted in 2.5.1.7.1. "Direct mortality", and 2.5.1.11. "Dormancy in vertebrate herbivores" with the effect 2.5.1.11.1. "Decrease of body weight and fecundity."

N.P. Naumov (1963, p. 241) reported about the Siberian marmot (tarabagan), Marmota sibirica that "Foraging at droughty summer is limited, and the next hibernation is usually accompanied by increased mortality of the animals, especially at late beginning of vegetation in spring." In this case as in the mice, it operates CESPPs 2.4. "Periodic (bottle-neck) suppression."

It was studied population dynamics of rodents, when CESPPs 2.4. did not operate. This was the case of the rat, Epimis rattus in India. The study was conducted by the Commission for Control the Plague in Belgaun. The report of the Commission for 1917 was cited by S.A. Severtsev (1941, pp. 181-183). The rats reproduced entire year. Fluctuations of their density had no any periodicity, and were weak - the difference between minimal and maximal values of it equaled 2 - 2.5 times. Taking into account of potential reproducing of the rats, percentage of their mortality was characterized as kolossal one. The only recorded cause of mortality was the plague, which affected the animals entire year.

This suggestion seems to be dubious. Obviously, food for the rats was not in abundance. It is probable the decrease of fecundity - "embryonic mortality" and other effects. This mortality factor in term of ESPPs is referred to as CESPPs 2.5.6. "Exhaust of adequate food", 2.5.6.1. "Mortality due to starvation or inadequate food in the same generation on the next one, decrease of fecundity." Because the plague did no excite complete mortality, it operated the attenuated strain of plague pathogen.

Selective mortality due to the plague was recorded, although only in the ground squirrels, Citellus spp. Being fatty, the ground squirrels in adult stage were rather tolerant to the plague, whereas in young ones, the mortality was high (Severtsev, 1941, p. 209).

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As to CESPPs 2.1.1.2.1. "Antibiosis to herbivores", it seems that in the case of ground rodents, it is expressed significantly only in roots of perennual grassy plants, whereas annual grassy plants often wiped out around of their colonies. This fact might be considered as an operation of CESPPs 2.1.2.1.1. "Supertolerance to herbivores." Protection of steppe ecosystems from destruction is provided mainly by diverse subcategories of CESPPs 2.5. "Effects of crowding."

4.2.2. Steppes and prairiesVertebrate herbivores, Hoofed animals

The hoofed herbivores are provided by forage unequally depending on the subcategories of the steppe. In meadow-like steppes, and true steppes, in most of years, they do not suffer from deficiency of food probably over all the year. This is so because two causes. Firstly, productivity of these ecosystems is high –up to 28 metric tons per hectare of above ground biomass in the meadow-like steppes, and up to 48 metric tons per hectare of it in the true steppes (Mordkovich, 1982, p. 28). Secondly, "Because the period of vegetation in steppes is prolonged – from April to October, the animals, in difference to forest and desert vertebrate herbivores, have fresh forage over a season in abundance…Special qualities of the steppe grass stand allow the stand to serve as valuable forage even in a dried state, in difference to forest grasses. According to A.N. Formozov, this "dry hay on roots" maintains activity of steppe hoofed animals over all the year. The thin snow cover allows them comparatively easily to obtain forage carefully prepared by a steppe phytocenosis. Steppe forage plants are very rich with mineral substances. Some grasses even exceedingly overloaded by salts. This explains an absence of the acute mineral starvation in steppe herbivores, which is very common in hoofed animals and rodents in the forest zone" (Ibid., p. 159).

The vegetation of meadow-like steppes consists of grassy species with diverse categories of resistance to hoofed herbivores. This becomes clear, when to consider the changes in vegetation depending on gradations of grazing (Larin, 1964, pp. 190-191). At a low level of grazing, it dominates the species with developed CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues." An increase of grazing leads to greater participation of the species with traits of CESPPs 2.1.1.2.1.1.1 ."Antibiosis to herbivores, Structural, Permanent", 2.1.1.2.1.1.2. “Antibiosis to herbivores, Physiological (biochemical), Permanent” or 2.1.1.4.1."Evasion from herbivores."

The plants protected by CESPPs 2.1.1.4.1., are of low height or early matured. They are Poa bulbosa L., P. pratensis L., Festuca pseudo-sulcata Drob., Trifolium alba L.

At heavy grazing, it dominates unpalatable grassy species – Salvia nutans L., Silybi pratensis L., Achilea millefolium L., and Euphorbia spp. They are protected by CESPPs 2.1.1.2.1.

In the true and dry steppes, the providing of hoofed vertebrates by forage is not continual. In these ecosystems, heavy summer droughts are common, and they are accompanied by ground fires. Because the roots are well protected against the fires, most part of steppe vegetation survives, but hoofed herbivores loss forage until next spring. Therefore, entering into operation CESPPs 2.4. "Periodic (bottle-neck) suppression" in a cooperation with CESPPs 2.2.2. "Natural enemies of vertebrate herbivores" is very probable.

The role of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" is also important. The well-developed root systems of the main part of steppe plants allow them to tolerate the foraging spending no resources for Antibiosis.

Nevertheless, among the cereals, there is the species having Antibiosis to vertebrate herbivores – the feather-grass, Stipa tortilis. This is the only species of fifty-seven ones in the genus Stipa of flora USSR, which is annual one, the rest are perennual species (Zhukovsky, 1938, p. 385). The latter are able to tolerate consumption by vertebrates.

The buffalo, Bison bison bison in prairie consumes nearly a half of above ground production of the ecosystems (K.E.F. Watt, 1968, cited in V.G. Mordkovich, 1982, p. 160). These animals

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do not suffer due to predators. Probably, starvation in winter is the only factor, which limits their density is the CESPPs 2.4. "Periodic (bottle-neck) suppression." The necessity to fodder them in severe winters, practicing in reserves, suggests in favor of this suggestion.

The foraging of wild hoofed animals in undisturbed by people grassy ecosystems was beneficial as to maintenance of their general stability. This suggestion is based on the practice of pasturing with gradient of intensity, in particular by V.V. Alyokhin (1934) in the Streletskaya Step Reserve. This scholar studied five stages of pasturing.

In the first stage, at the least intensity of the operation, species diversity of grassy plants became greater comparing that that in the intact state.

In the second stage, it took place the letting off of the feather-grass, Stipa spp, and an increase of participation of the brome strict, Bromus riparius Rehm.

In the third stage, it dominated Bromus riparius and Festuca sulcata Hack. The fourth stage was characterized by the singe species as a dominant – F. sulcata, which

was rather endurable to trumping out by cattle. In the fifth stage, the Bermuda grass, Cynodon dactylon Pers. became a dominant. At heavy grazing, it is possible selection of grass stand on dominance of very tolerant species

(Cynodon dactylon) or species with very developed Antibiosis –Artemisia austriaca., and the spurge, Euphorbia sp. (Mil’kov, 1956, p. 135).

An expression of the traits of Antibiosis and Tolerance to hoofed herbivores is in inverse dependence on capacity to compete in a grass stand. Therefore, at a lack of the foraging, the species with less Tolerance and Antibiosis became abundant.

The lack of grazing is actually destructive for steppe ecosystems. Such a concluion was drawn by V.V. Alyokhin (1986, pp. 188-193) at study on a situation in the Kamennaya Step Reserve. Here, in 1912 grazing and mowing were prohibited. The scholar observed this area in 1932. The prohibition was mainly kept. Comparing this area with those, where grazing and mowing were practiced, showed the significant changes in the reserved ecosystem. In it, it was formed a layer of died grass sometimes more 20 cm in thickness – a mulch. This mulch occurred to be non-penetrable for small and delicate plant species. Further, the upper layer of the soil became much humid. In a result, it disappeared early spring species – the hyacints, violets, several species of the family Liliaceae, and a number of species vegetating in summer. The domination was occupied by more robust and water-like species: Bromus inermis, Agropyrum repens, Calamogrostis epigeious, Gallum verum, Sesily libanotis, Euphorbia spp, Veronica spurea, and even ruderal species. The distribution of plant species lost a uniform pattern, and became paint one with dominance of some of the above species in spite of the soil conditions were the same.

As one may see, in undisturbed steppe ecosystems, vegetation and hoofed herbivores are in the symbiotic interrelations.

In dry steppes and desert-like steppes or semi-deserts, the situation with forage of hoofed animals differs comparing with that in the subcategories of SES 4.2.2. with better moistening. Due to prolonged dry period, which continues a half of year, life strategy of plants consists in completion of their life cycle as soon as possible in early spring, when moistening is sufficient. They confine the development in 1 - 1.5 months (Mordkovich, 1982, pp. 121-122). This scholar characterized development of these ephemers by the word "a sprint" (Ibid., p. 92). A short period of restoring of plant activity occurs in late fall, when precipitation takes place again. Thus, most part of year, plants in this area are in a dormancy. Although dry grasses are available in winter, hoofed animals suffer due to food deficiency over the period of plant dormancy. This implies on operation of CESPPs 2.4. "Periodic (bottle-neck) suppression" in a cooperation with CESPPs 2.2.2. "Natural enemies of vertebrate herbivores."

The steppe ecosystems undisturbed by people provided thriving of all their living beings – herbivores, predators of them and vegetation. Such a conclusion might be drawn on the base of reports of the persons, who observed the last rest of this splendor. Here are the data for the hoofed animals (ungulate) in the European Steppe Biome offered in the review by S.V. Kirikov, 1983, pp. 73-83).

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The grasses ecosystems were inhabited by the auroch, Bison bonasus L., the elk, Alces alces L., the deer, Cervus alaphus G., the roe, Capreolus capreolus L., the saiga, Saiga tatarica Pall., and the Prjewalski horse (tarpan), Equus przewalskii Gmelini Antonius. In XVIII century, the two latter species yet were abundant in steppes. "In "Description of the Little Russia", written by G. Junker in 1737 and published in 1764, it was mentioned that the saiga occurred in steppes of the Crimea Peninsula and Azov in herds, with the number of animals sometimes up to 10,000 individuals (Junker, 1764)" (Kirikov, 1983, p. 78).

The abundance of the tarpans is demonstrated by the quotation from P.S. Pogrebnyak (1968, p. 54): "It was fixated the case concerned summer of 1772, when from the fortress Kodak (near by of the contemporary city Dnepropetrovsk), it was sent an urgent message to St.-Petersburg about the offensive of a numerous Tartar horse cavalry from the Crimea. Soon, however, it became clear that the alarm was groundless: large herds of the tarpans passed by the fortress to the north. Their migration was provoked by drying out of grasses due to drought in steppes near by the Black Sea (Schillinger, 1931)."

French engineer G. Beauplan, who knew Ukraine well, observed in Steppes herds of the tarpans with fifty or sixty animals, and numerous auroches (les buffles) in north Steppe and Forest-Steppe (Beauplan, 1650, 1660, cited in S.V. Kirikov, 1983, p. 26).

In the same time, predators of the hoofed animals were abundant also. The wolf, Canis lupus L. was common. "In 1750-ies, every year, about four thousand skins of wolves and foxes were sold to Russia from Zaporozh’ye. Also, many skins of these animals were sent to Poland and Crimean Khan State" (Kirikov, 1983, p. 91). The wolves were numerous even in XIX century. In Ukrainian steppes, during two huntings in 1843 and 1845, it was killed about three thousand of wolves (Ibid., p. 92).

In the meadow-like steppes, the grasses were so tall that grazing livestock was unseen in the stem stand. This was observed in 1799 in steppes of Bessarabia (now Moldova), i.e. on the north-western borded with the Forest-Steppe biome (Sumarokov, 1800, p. 255, cited in S.V. Kirikov, 1983, p. 45).

In north steppes near by of the Dnieper River, in the beginning of XIX century, the height of grasses was like that in a field of the rye, Secale cereale. (Ibid., p. 45). The rye is a tall crop - about four feet. The old man, who spoke about that time to historical writer D.I. Evarnitsky in 1888, noted that to mow these grasses was a hard deal.

At last, in the south (dry) steppes, situated in the lower reaches of the rivers Danube and Dnieper (the Budzhak Steppe), the height of grasses reached two feet (Beauplan, 1650, 1660).

4.2.2. Steppes and prairiesInvertebrate herbivores

People, who had luck to visit steppes in past time, when they were not ploughing up or steppe reserves now, reported that in heyday of a season the vegetation was luxuriant, and insects were abundant. Russian poet I.S. Nikitin, who lived in the middle decades of XIX century, has written: "On the beautiful green carpet, In flowers’ fragrance, Myriad of bright insects, Flutter and non-stopping chirr."

A.A. Chibilyov (1990, p. 122), who has cited this verse in the book "The Face of Steppe", supposes that the bright insects are mainly grasshoppers and locusts, which dominate in the steppe insect fauna. They are bright, because expose in flight their inner wings of pink color frightening away numerous predators. Among the locust, it is common Calliptamus italicus L., which brings damage to fields of agricultural crops, but harmless in grassy biocenoses. In fact, grassy vegetation in the Steppe and Forest-Steppe biomes maintains a number species of locusts; some of them are tiresome pests of agricultural crops.

Consider the circumstances, which determine locust’s density. Now, in the southern part of East Europe, over a number of years, it takes place a serious damage of agricultural crops by several species of them, mainly Calliptamus italicus L. and Dociostaurus brevicollis Ev.

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Breeding grounds of these species in Ukraine are located in abandoned fields and overgraized pastures, from which they spread on fields of crops (Fedorenko et al., 2003). The same was noted in Siberia and Kazakhstan (Shchegolev et al., 1949, p. 321). A damage due to the species grows in the periods followed social perturbations, when vast areas of arable lands ocurred to be abandoned. In 1990-ies and 2000-ies, in steppes of Ukraine, it took place the outbreak of Calliptamus italicus L. Its density was High in abandoned fields with not too dense and not too tall grass cover, but in the prominent steppe Ascania Nova Reserve, its density was low (Fedorenko et al., 2003). The latter can be explained by activity natural enemies in an undisturbed biocenosis of the steppe reserve.

On natural vegetation in the Ascania Nova Reserve, damage due to the locusts is unnoticeable in spite of the reserve is surrounded by affected fields (V.M. Lobko, pers. comm.). Further, S.I. Medvedev (1959) reported that in the Ascania-Nova, the locusts Euchorthippus pulvinatus F.-W. and Omecestus petraeus Bris. are abundant species. Nevertheless, there are no reports as to destruction of this ecosystem. Obviously the activity of natural enemies in undisturbed steppe biocenoses is much greater than that in abounded fields or overgrazed pastures.

Again, the Morocco locust, Dociostaurus moroccanus Thnb. in northern areas of the range in steppes of Caucasus foothills has its breeding grounds in xeric habitats, where vegetation has been destroyed by heavy grazing. Here, decrease of an amount of precipitation is favorable for the locust, whereas an increase of precipitation leads to mass affection of the larvae by fungal phytopathogen, Empusa grylli Fres. (Shchegolev et al., 1949, pp. 321-322).

In southern areas of the range, where environmental conditions are very severe and these ecosystems have suffered due to heavy grazing over millenia, breeding grounds of the Morocco locust spread on all the areas. Here, suppressive effect is exerted by a definite weather situation, namely: drought, which results in starvation of locust’s larvae (Ibid., p. 322).

On the other hand, dense grass cover is unfavorable for High density of the locusts of diverse species. In such conditions, these insects suffer due to pathogens. It was recommended for control of the locust to maintain dense grass cover by means of regulation of grazing or irrigation (Ibid., pp. 325-326).

In northern Steppes and mesic grassy ecosystems of the Forest-Steppe biome, it inhabits the locust, Locusta migratoria rossica Uv. et Zol. Its range spreads from Middle Europe to the Tataria in foothills of the Urals Mountains (Bey-Bienko and Mishchenko, 1951, cited in O.P. Kryshtal, 1959, p. 142). This species is particulatly sensitive to density of grass cover. Its outbreaks took place in past time, when bare fallow was practiced widely (Shchegolev et al., 1949, p. 322). The outbreak of this species in Ukraine was recorded in 1923-1925, when it appeared vast areas of abounded fields in a result of the civil war (Kryshtal, 1959, p. 142).

Thus, SES steppe ecosystems as to invertabrate herbivores includes the following CESPPs: 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", CESPPs 2.1.1.4.1. "Evasion from herbivores", CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", as well as CESPPs 2.4. "Periodic (bottle-neck) suppression."

On the level ESPPs 3.1."Proper control", Dociostaurus moroccanus is suppressed by CESPPs 2.3. "Routine weather suppression." On the level ESPPs 3.3."Late control", it operates CESPPs 2.5.1.4. "Emigration in the adult stage in advance of food deterioration and/or exhaust" with final effect 2.5.1.4.1. "Mortality due to diverse factors."

Using the analogy of steppe grassy vegetation and cereal crops, it is logical to suppose an operation in steppes CESPPs 2.1.1.3.1.3. '''Tolerance to herbivores, Indifference to losses of host-plant tissues.''

As a whole, the steppe ecosystems are characterized by greater instability as to density of vertebrate herbivores comparing with forest ones. V.G. Mordkovich (1982, pp. 107-115) paid attention of this fact, and explained it by the evolutionary youth of these ecosystems. This view implies that in evolutionary young ecosystems, density of herbivores is regulated insufficiently, in particular due to deficiency of vertebrate predators.

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The problem is, however, what is cause of the deficiency. P. Farb (undated, pp. 154-155) supposed that in undisturbed by people prairies, activity of the predators was sufficient to keep rodents and insect herbivores on the level, at which outbreaks of all the herbivores were absent, and the vegetation thrived. The situation changed radically in XIX century, when prairies were converted in fields and pastures. In so doing, the predators were destroyed. Then, small rodents and insect herbivores began to reproduce in enormous numbers.

It is possible, that the enterprise conducted by the American pioneers was a repetition of the destruction that had been doing by their ancestors in steppes of Eurasia over thousands years.

Diverse groups of natural enemies are reported to be important in suppression of herbivores of the order Orthoptera (grashoppers and locusts). The predators are presented by birds and the flies of the family Asilidae. They hunt their preys in flight managing even large and potent insects as the tiger-beetles ( Chibilyov, 1990, p. 124).

The role of parasites and pathogens in affection of the Morocco locust and other species of Acrididae was considered by V.P. Pospelov (1939). This short article explains entire ESPPs to Acrididae species. It is very active the blister beetles, the family Meloidae, the genera Mylabris and Epicauta. Their larvae kill eggs of locusts in oothecas. A single larva of these beetles is able to consume all the eggs in an ootheca. In the adult stage, these beetles need in fresh plant tissues of diverse species for feeding. Therefore, the beetles are abundant in undisturbed grassy biocenoses. Droughts and grazing suppress vegetation that decreases activity of them.

The flies of family Bombylidae are active parasites of locusts’s eggs. It was recorded destruction by them 66% of ooothecae in the Crimea Peninsula. In the adult stage, they feed by flower nectar, so that droughts and grazing again unfavorable for them. The flies of the familly Sarcophagidae- Bloesoxipha lineata inject in flight their larvae on bodies of locusts. The number of parasitized adults reached 60% (Ibid., p. 12). The eggs are affected by parasites Scelio vulgaris resulting in 50-70% of mortality, and by mites of the genus Eutrombidium. As to the latter, percentage of host mortality did not stated, but they were so abundant that in spring the soil surface became red being covered by these mites.

The role of pathogens is considered as even more important than that of parasites. In wet season, it was recorded nearly complete mortality of adults in locust populations due to fungus Empusa grylli, the family Emtomophoraceae. By placing of locusts in cages with wet sand, it was shown that affection by the fungus took place at absence of source of infection, i.e. due to activation of the inapparent form of infection. When the first diseased insects appeared, the disease became very contagious.

The fungi Mucor exitious and Metarhizium anisopliae, as well as a number of bacteria species, especially Coccobacillus acridiorum were very active. The latter species was considered by the scholar as a symbiont of Acrididae, which normally inhabits their guts. Importantly, that keeping of the larvae at suboptimal ambient temperature (18°C) and high relative humidity (90%-100%) induced epizootics in them. The bacteria were observed in hemolymph of the insects. At transition of diseased on the early stage insects to the conditions of optimal temperature (25°C), they recovered. In the oothecae, locusts were affected by a number of pathogen species, especially fungi of the genus Isaria. Again, the epizootics took place at wet weather.

The above discourse explains, why in undisturbed steppe biocenoses, density of the grasshoppers and locusts does not reach the threshold of damage for dominants. The dense grassy stem stock provides optimal conditions for their natural enemies, and constitutes suboptimum for physiological state of these herbivores. Contrary, at overgrazing of these biocenoses and in agricultural articenoses, the microclimatic conditions are unfavorable for the natural enemies and optimal for the locusts.

The butterflies in steppe vegetation are unnumerous, but they abundant in thickets of steppe shrubs and on edges of forest islands.

The cereal flies are abundant. E.P. Narchuk (1981, p. 161) characterizes the cereal flies, Chloropidae by following words: "They are wide spread in Forest and Steppe biomes, especially numerous in open habitats: meadows, fields, abandoned fields... The stalk fly, Elaschiptera

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bimaculata Loew... develops in many wild grasses, cane, reed, reed-mice, sometimes in spikes of cultivated cereals."

The remarks as to common occurrence on wild grasses was given for hundreds insect species including serious pests as the frit fly, Oscinella frit L., the wheat stem maggot, Meromyza saltatrix L., the gout-fly, Chlorops pumilionis Bjerander, and others (Narchuk et al., 1981). The species known as tiresome weeds are common host-plants for species known as pests. Thus, the couch-grass, Agropyrum (Elytrigia) repens growing in arable lands often bears more signs of affection by the Hessian fly, Mayetiola destructor than the wheat does. This fact might be explained by abundant producing by A. repens of young sprouts, which favorable for development of the fly (Kryshtal, 1959, p. 206). Another weed, Roegneria trachycaulon is also affected commonly by the fly (Ibid., p. 206).

The same is true for numerous species of flies of the Chloropidae complex including the genera Oscinella, Chlorops and Meromyza: "The wheat is most attacked (29 species)… The specific composition and the number of species injurious to weed (Agropyrum repens) are almost the same as to wheat and barley" (Nartshuk, 1968, p. 365). The flies "…use of wild grasses primarily of weeds for their development" (Ibid., p. 366). A.F. Kryshtal (1974, p. 506) recommended to destroy an overgrowth of the Agropyrum repens by herbicides for protection of crops against Mayetiola destructor.

The sawflies, inhabiting in stems of matured plants affects wild species in the same rate as cultivated crops. Cephus fumipennis Ev. is recorded as pest of the Agropyrum repens and the wheat, whereas C. pygmaeus L. is common on wild grasses and again the wheat (Tryapitsyn and Zhelokhovtsev, 1981, p. 32).

The sunn bug, Eurygaster integriceps Put. is a serious pest of cereal crops in the Steppe biome. Nevertheless, it is known populations of this species, which limit their activity by wild grasses. G.A. Viktorov (1967, p. 200) has reported that "…there are settled mountain populations of E. integriceps steady connected with wild vegetation… in south Kirgizia in spite of presence of small areas of the wheat and the barley, the sunn bug is found out mainly on wild grasses, particularly Hordeum bulbosum." In the laboratory conditions, this species developed normally on the couch-grass, Agropyrum trichophorum, but its fecundity was much less comparing with that at feeding by the wheat (Ibid., p. 201).

As to probable CESPPs operating in the interrelations of steppe grasses and insect herbivores, beside with CESPPs 2.1.1.3.1.2."Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", one might see again CESPPs 2.1.1.4.1. "Evasion from herbivores."

In fact, A.Ph. Kryshtal (1951, pp. 122) has reported that summer generations of the Mayetiola destructor encounter with difficulties at search for sites of oviposition. Vegetation in typical for steppe habitats is unfit for oviposition, because their foliage is either too solid or dry. Therefore, the flies aggregate on small depressions, where moisture presents over greater time than on the main steppe area, young tillers arise during prolonged time, and plants are juicy. In the depressions, there are common diverse species of the genus Agropyrum.

In spring, when all the plants are in vulnerable for the fly stage, its density is not too High due to winter mortality, so that CESPPs 2.4. "Periodic (bottle-neck) suppression" operates also.

CESPPs 2.1.1.2.2. "Antibiosis to herbivores" probably does not play any role in self-protection of steppe grassy species against insect herbivores. For example, the fauna of pest insects of the cannabis, Cannabis sativa L. includes seventy-three species (Shchegolev et al. (1949, p. 525). There are no data about a choice of weakened plants by these species.

The role of parasites in suppression of insect herbivore species in steppe ecosystems has been studied thoroughly as to the sunn bug, Eurygaster integriceps Put. The vast review of literature and data of own studies are presented in the book by G.A. Viktorov (1967). He agrees with G. Remaudière (1961) as to the regularity having no exclusions, namely: the damage due to Eurygaster integriceps takes place in those localities, where monoculture of the wheat spreads on thousands and tens thousands hectares (Ibid., p. 244).

The cause of the affection consists in a lack of the conditions for existence of parasites of this species in a monotonous landscape at the vast crop monoculture. The parasites need in forest

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ecosystems, where they find additional insect hosts and places for hibernation. As an example of the opposite situation, it has been offered the case of the Ararat Valley in Armenia, where density of the sunn bug is continualy very Low. Here, in foothills and on mountain slopes, fields of cereals are of small areas and situated near by forest plots growing in defiles (Ibid., pp. 204, 208). This scholar considered the parasites as the main factors of suppression of this tiresome pest.

In contrast to the parasites, sunn bugs are good fliers. They are able to fly on large distance searching forest for hibernation, so that long distance to forest ecosystems from fields does not lay obstacles for their survivorship.

"Among natural enemies of the sunn bug, from the times of S.A. Mokrzhetsky (1894), N.N. Sokolov (1897) and I.V. Vasil’yev (1913), the main role has been attributed to egg parasites of the order Hymenoptera. The great majority of them belongs to the family Scelionidae (the superfamily Proctotrupoidae), and the minor part – to the family Encyrtidae (the superfamily Chalcidoidae)" (Ibid., p. 89).

"The fly parasites belonging to the subfamily Phasiinae of the tachinid family (Larvaevoridae) occupies the second place after the egg parasites… Of them, it is long ago known and often recorded in literature Clytiomyia helluo F., Phasia subcoleoptrata L., Ectophasia crassipennis F., and Helomyia lateralis Meig. Beside above-mentioned ones, others species are indisputable parasites of the sunn bug" (Ibid., p. 127).

The role of forest as a refuge of the parasites might be seen from the data on affection of eggs of the sunn bug in a cereal field depending on the distance to a forest edge (Shapiro, 1959). The percentage of the parasitization was as follows: near by the edge - 65.1%, on the distance 100 meters - 61.3%; 200 meters - 52.2%; 500 meters - 32.0%.

Predators kill also a significant part of a sunn bug population. On samples in sites of hibernation, the number of the bugs consumed by predators amounted from 21.6 to 73.7% (Viktorov, 1967, p. 180). K.B. Arnol’di (1955) evaluated mortality of the bugs due to predators as equaled 18-25% (Ibid., p. 179).

A decline of outbreaks of the sunn bug is proceeded with heavy affection by pathogens. Among them, the main are Beauveria bassiana and Spicaria farinosa (Ibid., p. 180).

In the above-cited book, G.A. Viktorov (1967, pp. 28-29) offered a review of literature, which demonstrates abundance of natural enemies of insect herbivores in natural grassy vegetation comparing with that in fields of crops. In particular, after ploughing of virgin biocenoses, density of parasite and predacious insects decreases in four - eighteen times (Grigor’yeva, 1962).

The above data might characterize the role of natural enemies in suppression of insect herbivores in the Steppe biome.

Plant species having distinct CESPPs 2.1.1.2.1. "Antibiosis to herbivores" (hoofed animals) quite suitable for feeding by insect herbivores. For example, the Artemisia austriaca is a favorable food for the beat webmoth, Loxostega (Pyrausta) sticticalis L. as well as plants of thirty-five families, although the clover, Trifolium spp. is ignored by this moth (Ivanov et al., 1938, pp. 67, 69). The corn borer, Pyrausta nubilalis Hb. is a species with a distinct polyphagy. In the USA, it consumes more 230 species of forty families. In USSR, it was recorded forty-seven varieties of cultivated plants and 101 species of weeds, which serve as a food for its caterpillars" (Shchegolev et al., 1949, p. 368).

4.2.2. Steppes and prairiesPhytopathogens

The phytopathologic literature has paid great attention on affection of wild grassy plants by phytopathogens, because the plants are considered as a source of affection of cultivated crops. These data allow suggest a character of the interrelations in biocenoses.

The stem rust, Puccinia graminis as only in XIX century was observed on 100 species of cereals (Cheremysinov, 1965, p. 85).

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The abundant data on this issue are offered by N.A. Naumov (1940). "The stem rust, Puccinia graminis Pers. – is most spread species of the rust on the cereals, which parasitizes on the thee vast number of them both cultivated and wild cereals" (Ibid., pp. 232-234). The list of affected genera is the following: Secale, Hordeum, Agropyrum, Bromus, Elymus, Festuca, Alopecurus, Dactylis, Lolium, Beckmania, Triticum (nearly all the cultivars), Avena, Agrostis, Anthoxanthum, Arrehenatherum, Holcus, Koeleria, Phalaris, Phleum, Deschampsia, Poa, Aira, Calamagrostis, Apera, Briza, Trisetum, and others. About 300 species of the cereals have been known as host-plant of this species.

The crown barley rust, Puccinia coronifera Kleb. was recorded on the genera Agropyrum, Alopecurus, Arrhenatherum, Avena, Bromus, Calamagrostis, Festuca, Glyceria, Holcus, Lolium, Secale, Dactylis, Poa, Phalaris, Scolochloa (Ibid., p. 241).

The wheat leaf rust, Puccinia triticina is known on the genera Secale, Elymus, Aegilops, and Hordeum (Ibid.,p. 245).

The wide range of host-plants among wild cereals is shown for several other species of the rust, and powdery mildew, Erysiphe graminis, the ergot, Claviceps purpurea.

K. Norari et al. (1996, p. 147) reported that for the yellow rust "in hot and dry weather conditions in Iran, wild grasses seems to be the only overwintering hosts, because volunteers wheat in such conditions usually does not survive… Sixteen species from five genera of Gramineae, which were heavily infested with yellow rust, were collected from different parts of Iran."

The wild cereals serve as a source of infection of the septoriosis, Septoria spp. on the winter wheat in Ukraine (Kluchevich, 2004). This scholar observed the affection of the following species up to such a percentage of a leaf surface: Dactylis glomerata L. – 3.1%, Alopecurus pratensis L. – 6.5%, Festuca pratensis Heeds – 8.6%, Agrostis vulgaris With. – 14.1%, Agropyrum repens (L.) Nevski - 37.4%, whereas the winter wheat was affected by the septoriosis on 3.6% – 58.7% in the Forest biome, and 1.5% - 44.8% in the Forest-Steppe biome.

The signs of affection by the above phytopathogens are common in biocenoses that, however, do not suppress vitality of the plants. This fact suggests an operation of CESPPs 2.1.1.3.2. "Tolerance to phythopathogens."

4.3. DesertsVertebrate herbivores, Tortoises

Many data valuable for understanding of SES of desert ecosystems are offered by A.N. Formozov (1958).

It should begin the discource with a hervivore species having unique traits, which fit ideally to the severe desert environment. The tortoise Testudo horsfieldi Gray. spends in dormancy 9-10 months per year. These animals are active 2-3 months in spring, when plant ephemers thrive. At disappearing of the ephemers, they lay eggs, and dig into the soil making own burrors on the depth a meter or using burrows of other animals. The yongsters hatch in the same summer, and also find shelter in the soil until next spring without feeding. The species is prosperous. In early spring, youngsters of this species are too abundant that ''can be gathered by vans'' (Ibid., p. 400). The tortoises are considered as tiresome pests, which bring danger to pastures and to agricultural crops in oases.

What kinds of CESPPs suppress the tortoises? Probably, they are predators. Foraging of the tortoises is a feast for snakes, predacious birds, weasels, foxes, wolves, and cats. Only a little part of the brood survives to adulthood. In fact, several tens of the adult tortoises per hectare are considered as High density, which endangers pastures and crops. (Ibid., p. 401). The damage of pastures and crops by the tortoises might be explaned by destruction of their predators near by settlements. However, as a whole, desert ecosystems are much rich by these animals than that steppe ones. This fact can be explaned by that in deserts, even now, vast areas are scarcely populated.

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Hence, in this case, it operates CESPPs 2.2.2. ''Natural enemies of vertebrate herbivores, 2.2.2.2. ''Predators.'' It is obvious the significant role of CESPPs 2.1.1.3.1.2. ''Tolerance to herbivores, Repair or compensation of losses of host-plant tissues'' and CESPPs 2.1.1.4.1. ''Evasion from herbivores.''

4.3. DesertsVertebrate herbivores, Soil-dwelling rodents

Deserts of the Middle Asia of the Former Soviet Union (now, it is used the name Central Asia) are characterized by rich fauna and abundance of the rodents digging burrows in the soil. They are thirteen species of the Jerboa, Allastaga spp., four species of sandy mice, Meriones spp. and Rhombomys opimus Licht., two species of ground squirrels, Spermophitopsis leptodactyus Licht., and Citellus fulvus Licht., the grey hampster, Cricetulus migratorius Pall., the house mouse, Mus musculus L., the small-eyed mouse, Ellobius talpinus Pall., the shrew, Diptomesodon pulchellum Licht. and the porcupine, Hystrix leucura Sykes (Formozov, 1988, pp. 401-408).

The large sandy mouse, Rhombomys (Gerbillus) opimus Licht. is considered as the most serious pest, and its life history is described rather detaled that allows to propose some suggestion as to CESPPs, which suppress this species (Ibid., pp. 404-407). It is common in sandy habitats, where a family of the animals digs a group of burrows with long tunnels and numerous outlets. This activity is aimed to approach stealthy to forage plants, to store hay for winter, and to hide themselves from predators, which are able penetrate in such burrows. This species uses as a food very diverse plant species. Within the radius up to 75 meters from a burrow, actually all the plants are often destroyed. The mices do not move on larger distance from their outlets.

In SES of deserts as to this species, it if probable an operation of CESPPs 2.4 "Periodic (bottle-neck) suppression" and 2.5 ''Effects of crowding." It is reported that in spite of storing of hey in the burrows, winter mortality of the mice is high. In fall, in every family, it is common over fifteen animals, whereas in spring, the number decreases to the two-three mice. There are years favorable for reproducing of the mice, when their burrows fuse in colonies with many thousands of outlets. Obviously, in these years, operation of CESPPs 2.4. "Periodic (bootle-neck) suppression" becomes less due to weather situation favorable for producing of biomass of mice's forage.

The mice suffer due to diverse diseases. Among them, it is the leishmaniosis, whose agent is vectoring by the gnat Phlebotomus sp., which inhabits mice's borrows; the typhus vectoring by the mites Ornithodorus spp. These diseases are pathogenic for people. It is known abandoned colonies of the mice that suggests destructive effects of the pathogens.

It is reported about high activity of mice's predators, especially the mephitic weasel, Vormela peregusna Güeld (Formozov, 1988, pp. 412-413). It is able to penetrate into burrows of the sandy mice and kill all their inhabitants over one-two days. This species, however, is not able to pleclude the growth of its preys, until the pathogens enter into operation. In such years, resident foxes also become abundant – several subspecies of Vulpes corsac. Fluctuations of their density are similar to those in the polar fox in the Tundra ecosystems.

The composition of desert SES as to soil-dwelling rodents on the example of the mice is as follows: CESPPs 2.4. ''Periodic (bottle-neck) suppression'' and CESPPs 2.5. ''Effects of crowding'', when CESPPs 2.4. becomes weak. It is probable an operation the following effects of CESPPs 2.5.: 2.5.1. "Deterioration and/or shortage of food", 2.5.1.4. "Emigration in the adult stage in advance of food deterioration and/or exhaust", 2.5.1.4.1. "Mortality due to diverse factors", 2.5.1.10. "Decrease of body weight at shortage of food and/or forced feeding by inadequate food", 2.5.1.10.1. "Decrease of fecundity and increase of mortality due to weather stress", 2.5.2. "Attraction of predators and parasites, increase of their searching activity", 2.5.2.1. "Mortality under effect of predators and parasites", 2.5.3. "Increase of activity of pathogens and parasites in specific conditions of high host density", 2.5.3.1.4 "Mass mortality due to affection by acute form of infection and parasitization", 2.5.4. "Fluctuations of herbivore host resistance to

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pathogens and parasites as well as virulence of pathogens and aggressiveness of parasites", 2.5.4.1. "Suppression of herbivores over the period, which provides a reprieve for restoring of vitality of dominants", 2.5.5, "Disturbance of media of inhabitation", 2.5.5.1. "Affection by pathogens due to deterioration of sanitary state of the media."

Heavy foraging effect within colonies of the mice results in changes of desert ecosystems. On places of the adandoned colonies, it appears an open wood ecosystems: a desert scrub with the saksaul, Haloxylon spp. as a dominant (Ibid., 406). Thriving of these species is promoted by enrichment of the soil due to products of vital activity of the mice, and by a lack of plant competitors. These facts give the ground to suppose an operation of CESPPs 2.1.2.3.1. "Supertolerance to herbivores." It participates in the process of succession of the desert ecosystems.

4.3. DesertsVertebrate herbivores, Hoofed animals

The character of SES of desert ecosystems as to hoofed animals becomes clear from the text quoted below. This is description of foraging of the Prjewalski horse in the Gobi Desert (the Jungary), which has been offered by V.V. Klimov (1990, pp. 98-100). "Spring comes in the Central Asia lately. Only in May, valleys and slopes of low mountains become covered by green vegetation. Over previous winter, the horses fed by dried parts of sedges, cereals, mugworts, salt-plants (the genus Salsola), as well as by large-stalk species, which kept moisture long time – Astragalus spp. and Ferula spp. The spring moisture and warm are used by the ephemeric plants, which, however, are scarce in this area. Because these plants are poisonous, the horses keep themselves away searching for dried bunches of Stipa spp. and Festuca sulcata. When spring come in a bloom, although this is summer according to the calendar, the ephemers disappear and are changed by steppe cereals and onions. In this period, in the horse’s diet, it appears fresh Fistula sulcata, Agropyrum spp, Bromus spp., Poa spp., and Stipa spp. The horses migrate in foothills, where F. sulcata is abundant. They feed on meadows in lowlands. Nevertheless, they prefer more nourishing desert cereals."

Progressing of summer hot results in ever-increasing dormancy of plant species. The cereals disappear by the first. And the horses are forced to migrate searching for those plants, which are able to keep green parts – Salsola spp. Haloxylon spp., Tamarix spp., Ephedra spp., and Astragalus spp.

The fall rains begin in August and the desert becomes green again for short period. Its duration is very important for the horses as to accumulation of an energy store in their bodies.

In winter, the soil surface is covered by ice. The horses need to break ice to obtain forage, which is scarse. In this period, Salsa plants, which before are nearly ignored by the horses, become palatable. Further, it is used dried stalks of other species and even own excrements. The latter contained incompletely digested forage.

The things become worse at an onset the weather situation, when the forage is inaccessible. In so doing, the soil surface is covered by thick layer of ice. The animals are unable neither to feed, nor drink. This phenomenon is called in Mongolian "tsaganzud"- the white cover. In so doing, wild animals and cattle on open area perish. The situation is especially catastrophic, if the tsaganzud is accompanied by the mighty winds with snow. It is known the cases, when hundreds of thousands of wild animals of diverse species and cattle die at such weather. Only those animals, which occurred in foothills, where snow is accumulated, survive.

In addition, the horses and other species of hoofed animals are endangered by "kharazud" (the black cover) – a summer drought.

It is obvious that CESPPs 2.4. "Periodic (bottle-neck) suppression" plays very important role is suppression of vertebrate animals in desert. The effect of these CESPPs and a pursuit on the part of people resulted in an extinction of this species in the Gobi desert – the last refuge of the species in nature. The horses have not been seen here from 1947.

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Vertebtate hervivores encounter with host-plants having the well-developed protection of the category 2.1.1.2.1.1. "Antibiosis to herbivores, Structural." This CESPPs significantly limits consumption of the plants with such traits, but not precludes it completely. These traits protect absolutely matured tissues, but juvenile tissues are susceptible. This idea allows understanding, why the camels, Camelus spp. are able to use as a food the camel’s thorn, Alhagi camelorum, whereas the alpaca, Lama pacos feeds by the prickly pear, Opuntia spp.

4.3. DesertsInvertebrate herbivores

For understanding SES of deserts as to insect herbivores, it is important to take into account that these ecosystems are teemed by predators of them. They are the main food of lizards, which are so abundant from early spring to late fall that deserts of the Middle Asia is called "the country of lizards" (Formozov, 1958, p. 378). "A continual appearing of lizards for a moment before a pedestrian or a rider is a typical picture of nature in the Middle Asia" (Ibid., p. 398). Deserts of this region are inhabited by thirty-five species of the lizards. They pursue insects even on tops of shrubs, where lizards climb for feeding by plant tissues and to save themselves from a scorching surface of the soil in day hours (Kashkarov, 1938, p. 566). Further, insect herbivores encounter with ravenenous and abundant predators - rodents and ants on a surface of the soil, and birds and bats in the air.

Due to such circumstances, "In deserts, the first place among large insects is occupied by beetles, especially dwelling in the larval and adult stages in the soil and feeding by plant roots or in stems of shrubs. The locusts inhabiting the soil surface are much less numerous…" (Formozov, 1958, p. 378). Further, "In typical desert habitats, the locusts…have less density than that in steppes. In deserts, the density does not exceed one-two insects per square meter, and usually is less than one insect" (Ibid., p. 394).

Nevertheless, the locusts are able to reach High density. In fact, they "exert heavy damage to crops and pastures" (Ibid., p. 390). The abundant species of these insects, the Morocco locust, Diciostaurus maroccanus Thubg., and the Turan locust, D. nigrogeniculatus Tarb. are adapted well to the desert conditions (Ibid., p. 390, p. 394). These species fulfil their development during two months – from mid of March to mid of May, i.e. in the period of flourishing of ephemera. The rest of year, they spend in the egg stage. Their eggs are well protected from diverse stresses, including soil treatment by people. The eggs are laid in oothecae, which are deepened into the soil on the distance up to 80 cm, whereas the locust’s oothecae in steppe ecosystems are deepened up to 16 cm.

The composition of SES in desert ecosystems as to locusts might be elucidated if consider the detailed report about the desert locust, Schistocerca gregaria Forsk, offered by N.S. Shcherbinovsky (1952). Outbreaks of this species arise in certain areas of subtropic and tropic deserts after abundant monsoon rains, which result in flushing of vegetation. This fact suggests that among CESPPs, which keep density of this species on the Low level, it takes part the category 2.1. “Plant resistance to PPs.”

This suggestion needs in a sidelight. The range of the host-plants is very wide – up to 400 species (Ibid., p. 342). Among the preferred plants are those, which are common at absence of abundant rains, in particular the camel’s thorn, Alhagi camelorum, Karelinia caspica and Salsola kali (Ibid., p. 349). However, such plants are adequate as a food, probably, only for the imagoes and the larvae in older instars. As to the larvae in young instars, they need in juvenile tissues of host-plant tissues – young tillers.

This suggestion is based again on the data cited in the above book (Ibid., p. 355). “Indian entomologists” studied development of Schistocerca gregaria from larval hatching to oviposition on diverse plant species with two categories of muturity – “fresh” tillers and fully matured (“old”) tissues. It was found out that feeding by old tissues decreased all the indices of vitality, in particular at feeding by Heliotropium undulatum, the number of oothecae per female was 2.0-4.4., whereas on old tissues – 0.3.

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Importantly, in this study, it was shown that on the dry soil the female are unable to insert their oothecae deeply. They occurred on the soil surface.

Thus, at the period of low rains, which continies from two to seven years, Low density of Schistocerca gregaria is maintained first of all by deficiency of adequate food, i.e. it operates CESPPs 2.1. “Plant resistance to PPs.” Probably, this is 2.1.1.2.1.1.1. “Antibiosis to herbivores, Structural, Permanent”, which suppresses a locust population killing its larvae of young instars.

In a cooperation with this CESPPs, it operates 2.2.1. “Natural enemies of invertebrate herbivores.” They are diverse (Ibid., pp. 362-365). Among them, there are larvae of parasitic flies, which affected nearly 100% of oothecae in some areas, numerous species of birds, lizards, hedgehog, and ants. In the dry conditions, when growth of a locust population is limited, and the oothecae are badly protected, these natural enemies are able to keep the density on Low level. Contrary, at abundant rains, when growth and protection of populations are high, activity of natural enemies is unsufficient to keep the density on the Low level. In this SES, it operates also CESPPs 2.3.11. “Drought devastating of food resource” with the effect 2.3.11.1. “Mortality due to starvation and emigration.”

Thus, depending on the weather situation, ESPPs as to Schistocerca gregaria is situated either on the level 3.1. “Proper control” or on the level 3.3. “Late control.” In the latter, it operates CESPPs 2.5.14. “Emigration in the adult stage in advance of food deterioration and/or exhaust” with the effect 2.5.14.1. “Mortality due to diverse factors.”

In the reservations, it takes place the initial outbreaks of Schistocerca gregaria. Due to the migrations, which are directed in areas with recent raining, it arises the advanced outbreaks of this species. Probable CESPPs, which induces decline of the advanced outbreaks, is 2.5.3. “Increase of activity of pathogens and parasites in the specific conditions of high density” with the effect 2.5.3.1.4. “Mass mortality due to affection by acute form of infection and parasitization.”

These suggestions might be spread on other species of locusts in the Desert biome - the Morocco locust, Diciostaurus maroccanus Thubg., and the Turan locust, D. nigrogeniculatus. Although, their population dynamics differs from that in Schistocerca gregaria having no the regulatity. This is so because in deserts of the temperate climate, the periodicity of moistening is much less regular.

The lepidopterous herbivores also spend their preimaginal stages in shelters – in the soil, especially in loose sand, where they feed by roots, or inside of stalks, stems, and fruits. Nearly all of them are night butterflies of the families Noctuidae, Syntomidae, Pyralidae, and Cossidae (Ibid., p. 378). These traits are rather effective as protective ones not only from high air temperatures in day hours, but also against predators. It was recorded an active flight of butterflies, especially noctuid moths on light. At morning twilight, they hide themselves in diverse shelters (Ibid., p. 374).

The role of parasites in suppression of insect herbivores is little of probable, because production of nectare (imaginal food of the parasites) in xerophitic plants is very low (Ibid., p. 379). Further, high air temperatures in day hours are suppressive for parasites. The xeric environment is unfavorable to pathogens of insect herbivores.

SES of lepidopterous herbivores in desert ecosystems includes CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", 2.2.1.2.1. Vertebrate predators" and 2.2.1.2.2. "Invertebrate predators" (the ants).

As to self-protection of desert plants against lepidopterous and sap-sucking herbivores, it is probable an operation of CESPPs 2.1.1.3.1.2. ''Tolerance to herbivores, Repair or compensation of losses of host-plant tissues.''

This suggestion, however, is based on the very limited number of case stories. They concern suppression of the prickly pear, Opuntia spp. with introduced enemies the Argentine moth, Cactoblastis cactorum Berg. in Australia, and the cochineal insect, Dactylopius opuntiae Lichtenstein introduced from Hawaii to an island near by the cost of southern California. In the both cases, it was achieved the effective suppression of the weed.

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It is noticeable that the suppression has been recorded over many years: forty years in Australia (Huffaker et al., 1971) and eighteen years in California (Andres and Goeden, 1971). The fact of prolonged keeping of susceptibility of the very succulent plant to its insect pests suggests on absence of the trait of Antibiosis to consuments of these groups.

4.3. DesertsPhytopathogens

Arid climate of deserts is unfavorable for activity of phytopathogens. It is not available the data as to affection of vegetation in deserts due to these PPs. Therefore, it is logical to suppose that desert vegetation is protected against phytopathogens mainly by CESPPs 2.3. "Routine weather suppression."

4.4. TundraVertebrate herbivores, Hoofed animals

According to I.V. Larin (1964, pp. 180-181), the following types of vegetation are used as food for the reindeer, Rangifer tarandus in the tundra:

i) Brushes. Several species of willows, Salix spp. and birches, Betula spp. up to 60 cm in hight. They are grazed in spring, summer, and early fall.

ii) The lichen, Cladonia spp. and Cetraria spp. They are the main food in winter – from mid of September to end of May.

iii) The sedges, Carex spp. and cereals, Graminaceae spp. They are grazed mainly in the second part of May, in June, in fall (regrowth after spring foraging), and winter (from snow cover).

In the above publication, the mosses, Bryophita spp. are not shown as a forage of the reindeer, although according to another report, their participation in all the food stock reaches 17% in spring, 15% in summer, 25% in fall, and 40% in winter (Tishkov, 1984). These data concern all the range of this species.

According to the review of literature in the above-cited article, the moss as a food is inferior to other plants due to diverse factors. The mosses contane many lignin, cellulose and "cell’s walls," toxic glycosides, polyurone, and dicrane acids, whereas in them it is a little of a number of important amino acids (metionine, triosine, triptophane). In mosses, however, there is the unsaturated arakhidone acid, which protects cell membrames of animals against low temperatures (Prins, 1982). Therefore, in fall and winter, the consumption of mosses increases. As a whole, mosses are suitable as an additional foodstuff, rather than as the main forage. Participation of the mosses in the food increases on the pastures exhausted by overgrazing.

The mosses are protected as to consumption by the reindeer by CESPPs 2.1.1.2.1.5.1. "Antibiosis to herbivores, Nutrient inadequacy of host-plant tissues, Permanent." Other groups of tundra plants are protected by CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues." These CESPPs are effective on condition that they operate in cooperation with 2.4. "Periodic (bottle-neck) suppression" and 2.2.2. "Natural enemies of vertebrate herbivores", 2.2.2.2. "Predators."

The effect of predators (the wolves) is not only a decrease the density of the reindeers. It is important a persistent chasing of the herds by wolves, so that the vegetation was eaten a little in any place.

The suppressive role of pathogens is also significant as it was shown by G.I. Tanfil’yev (1911). He recorded affection of reindeers by a very contagious disease, probably, the anthrax. The mortality spreads on hundreds domesticated reindeers over a few hours (Ibid., pp. 224-225). Abundant gnats serve as potent vectors of the disease. The disease also affects wild reindeers. Due to deficiency of calcium, they gnaw bones of died kins. In cold climate of tundra, the infection retains long time.

The suppressive effect of predators and pathogens keeps density of the reindeers on the level from four or five animals per 1 sq. km, that is tolerable to vegetation. The animals move nearly

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continually biting off tops of plants. Such a limited consumption is vitally important for survivorship of the lichens, whose increment is very low - up to seven mm per season (Ibid., pp. 34-35).

The traditional nomad behavior of the native humans does not actually disturb this harmony. Contrary, the usage of a settled economy, which maintains the herds with many hundreds of animals and eliminates predators, leads to the consumption of tundra vegetation at winter foraging on the rate, which exceeds its possibility to tolerate the grazing. This results in starvation of the animals, growth of the number of diseased animals due to a lack of natural selection, and mass mortality of them.

Such events have been described by F.F. Darling and A.S. Leopold (1953); A.S. Leopold and F.F. Darling (1953).

4.4. TundraVertebrate herbivores, Soil-dwelling rodents

The lemmings, Lemmas, Myopia schisticolor, and Dicrostonyx torquatus unlikely to the reindeer prefer to feed by the mosses. A.A. Tishkov (1984) offers the review of literature for five species of the lemmings. They use these plants for food over all the year. A participation of the mosses in the food reaches 80% in summer and 96% in fall over all the range. The adaptation of the lemmings to mosses as the main food is verified by structures of their inner organs, which have traits directed on digestion of food with abundant ballast substances. In the animals, it was found out an increased hindgut and modifications of kidneys.

Thus, in SES of tundra ecosystems as to the lemmings, it is probable an operation only one CESPPs 2.1."Plant resistance to PPs" – 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

What kinds of CESPPs cooperate with 2.1.1.3.1.2.? Inhabiting in burrows provides the lemmings by good protection against predators if their density is not too High. Because they are adapted well to consume of the tundra vegetation, deficiency of food is hardly to be the problem for them. Therefore, the lemmings reach the overcrowding easily, that in circumstances of abundance of gnats characteristic for the tundra, causes the affection of a population by pathogens. So that, the cooperators of CESPPs 2.1.1.3.1.2. belong to CESPPs 2.5. "Effects of crowding."

Of them, there are probable the following: 2.5.1.4. "Emigration in the adult stage in advance of food deterioration and/or exhaust", 2.5.1.4.1. "Mortality due to diverse factors", 2.5.3. "Increase of activity of pathogens and parasites in specific conditions of high host density" 2.5.3.1.4. "Mass mortality due to affection by acute form of infection and parasitization", 2.5.3.1.6. "Mortality due to inadequate behavior", 2.5.4. "Fluctuations of herbivore host resistance to pathogens and parasites as well as virulence of pathogens and aggressiveness of parasites", 2.5.4.1. "Suppression of herbivores over the period, which provides a reprieve for restoring of vitality of dominants."

4.4. TundraInvertebrate herbivores

The invertebrate fauna of the mosses in the tundra are rather rich (for review see A.A. Tishkov, 1984). It includes nematodes, mollusks, mites and insects – beetles, butterflies, flies, bugs, aphids, and coccids. The reports about a noticeable damage by them are unknown. In the given case, it is probable an operation of CESPPs 2.3. "Routine weather suppression" and CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

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4.4.TundraPhytopathogens

The data on affection of the tundra vegetation by phytopathogens are unavailable. An activity of them seems to be low due to low ambient temperatures that implies high activity of CESPPs 2.3. "Routine weather suppression."

4.5. Forest-TundraThis formation differs from the Tundra by presence of scattered depressed trees or island groves of the trees. Here, it is common the pine, the spruce, the larch, the birch, and the willow.

4.5. Forest- TundraEvergreen coniferous species, Coniferales

The north border of the range of some needle-eating defoliators goes behind the southern edge of the biome. For most of the species, this area concerns to the W.C. Cook’s zone (d), where density of the species is suppressed to the unnoticeable level by CESPPs 2.3. "Routine weather suppression." The suppression is possible without operation of CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent" and 2.2.1. "Natural enemies of invertebrate herbivores."

In Central Europe, in mountains above the forest belt (the elfin woodland), i.e. in the conditions similar to the Forest-Tundra biome, it was recorded weak damage of needles on the brushy pine species - the mugo pine, Pinus mughus Scop. with the European pine sawfly, Neodiprion sertifer during one season (V.I. Grimal’s’ky, pers. comm.).

4.5. Forest- Tundra,Deciduous coniferous species - the larch, Larix spp.

In the Siberian Forest-Tundra, it is known defoliation of the larch by Zeiraphera diniana. Probably, this is a result of migration of the moths from the south. In such severe conditions, the resident population of the moth is hardly able to exist. Nevertheless, this species has a chance to complete its life cycle during the short northern summer. For this species, it is the W.C. Cook’s zone (c). Here, it operates CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" in cooperation with CESPPs 2.3. "Routine weather suppression."

4.5. Forest- TundraDeciduous Angiospermae tree species

The insect defoliators of brushy species Betula tortuosa and Salix phylicifolia in the northern forest-tundra were studied by I.A. Bogachyova (1984). It was found out four groups of the insects.

i) Spring. The fall spanworm, Oporinia autumnata on both above species. On the willow, Phyllodecta pallidus L. (Crysomelidae) and Epinotia cruciana L. (Tortricidae).

ii) Summer. On young leaves of the birch. Polydrosus ruficornis Bonsd. and Phyllobiuis maculatus Tourn. (Curculionidae), Tenthredinidae, Pamphilius sp., leaf-mining Leucotera spp. and the spanworm Cidaria hastata L. On the willow. Phyllobius viminalis L.

iii) Summer. On matured leaves of the birch and willow. Tenthredinus jakovleffi Knw., and Tenthredinidae sp.

iv) Summer and fall. Tenthredinidae spp. and leaf-miners.The species, which feed by matured leaves, often are unable to finish their development until

an onset of frost. The observations over thirteen years revealed a low rate of the consumption of a leaf surface – a few percents in young leaves and up to 8% in matured ones.

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Thus, species composition of defoliators in resident dominants (dwarf species of the birch and the willow) occurred to be rich. But they consume a negligible part of the leaf area. Nothing is known about a presence of their natural enemies. Continual Low density of the defoliators is a result of operation of CESPPs 2.3. "Routine weather suppression" This area should be considered as belonging to the W.C. Cook’s zone (c).

The probable CESPPs operating in this case are 2.3. "Routine weather suppression" and 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

4.5. Forest-TundraStem borers

Stem borers spread their activity on the Forest-Tundra biome. They are suppressed by CESPPs 2.1.1.2.1.2. "Antibiosis to herbivores, Physiological (biochemical)" and 2.3. "Routine weather suppression."

4.6. Bogs

The bog is "A community dominated by mosses; found in regions of high rainfall and poor drainage"(Godman and Payne, 1979, p. 333).

4.6. BogsVertebrate herbivores

It is unknown the cases of noticable consumption of mosses by vertebrate animals in areas of temperate climate. Here, it operates CESPPs 2.1.1.2.1.5.1. "Antibiosis to herbivores, Nutrient inadequacy of host-plant tissues, Persistent."

4.6. BogsInvertebrate herbivores

The humid media of mosses promotes activity of pathogens of arthropods, so that it is probable an operation of CESPPs 2.2.1. "Natural enemies of invertebrate herbivores", 2.2.1.3. "Pathogens."

4.6. BogsPhytopathogens

A protection against phytopathogens is provided by active antibiotic substances (Banerjee and Sen, 1979). Here, it operates CESPPs 2.1.1.2.2.2. "Antibiosis to phytopathogens, Physiological (biochemical)."

4.7. Fens

The fen is "A community dominated by reeds and sedges…" (Godman and Payne, 1979, p. 333). In fens, Carex pseudo-cyperus L., C. vesicaria L., C. riparia Curt., and C. caespitosa L. are abundant as well as the reed, Phragmites communis Trin. and Deschampsia caespinosa (L.)

4.7. FensVertebrate herbivores

The sedges have the following traits important concerning ESPPs against vertebrate herbivores: large and very tough leaves, which are favorable as forage only up to the spiking stage. Beginning with the stage of flowering, haying of this grass is undesirable, because it is eaten badly by cattle (Larin, 1964, p. 123). Thus, sedges are protected against vertebrate herbivores by CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses

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of host-plant tissues" in the juvenile stage and CESPPs 2.1.1.2.1.1. "Antibiosis to herbivores, Structural" in the mature stage. The same CESPPs are known to operate in these ecosystems in self-protection of the reeds.

4.7. FensInvertebrate herbivores

On the reed, it was found out rather rich fauna of insect herbivores typical for the cereals (V.A. Lozinsky, pers. comm). Here, it operates CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues." and 2.1.1.4.1. "Evasion from herbivores", 2.2.1. “Natural enemies of invertebrate herbivores.”

As an example of insect defoliators in such habitats, it can serve the meadow armyworm, Cirphis unipunctata Haw. (Engelhardt, 1929). Here is the characteristic of population behavior of this species: “The armyworm is closely connected with presence of water; its favorable habitats are damp meadows with dense flush cereal vegetation (Calamagrostis landgsdorfii Trin. C. neglecta P.B.), sedges (Carex meyeriana Kunth and others), shores of small rivers and lakes overgrown by the sedges and the reed, Phragmites communis Trin., the wild rise, Zizania, and other plants. On more elevated sites, slopes of hills and everywhere with the well-drained soil and sparse vegetation, outbreaks of the moth have not been observed” (Ibid., p. 75). Nevertheless, “Everywhere, this armyworm is concerned as a dangerous pest of field crops, especially in the United States and Canada” (Ibid., p. 75).

The data about natural enemies of the moth were presented for agricultural crops at the decline of an outbreak. The caterpillars and pupae were affected by ichneumonid and tachinid parasites (42% of parasitization). “The most serious enemy was the carabid beetle, Calasoma chinensis Kirby and its larva…In the fields with caterpillars of the armyworm, density of the larvae reached 95 insects per square meter” (Ibid., p. 78).

4.7. FensVertebrate herbivores

The mask-rat, Ondatra zibethica L. is not fastidious as to food. “Actually, there are not such water and fen plants, which musk-rats do not eat. They eat reeds, sedges, rushes, shave-grass, water-lilies, duckweed, and others” (Pantyukh, 1986, p. 171). Matured musk-rats grind rigid plant parts in a thin gruel and feed by it their brood. Nevertheless, young and juicy shoots are favorable for forage. In summer and early fall, musk-rats search for young roots, especially the sweet-flag, and again shoots. In late fall and winter, they eat roots, seeds, and winter buds of plants (Ibid.).

In mask-rats, it is well-developed the protection of a plot of inhabitation against intraspecies intruders; signs of heavy wounds are common on skin of the matured males, sometimes the males perish in the tournaments (Ibid., p. 169). Further, musk-rats suffer due to numerous species of predators; the herons and the silurus are tenacious enemies of the youngsters (Ibid., pp. 168, 172) .

ESPPs as to these animals is provided by a cooperation of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", 2.1.2.3.1.1. “Supertolerance to herbivores. Compensation of losses of host-plant regeneration”, and 2.2.2.2. “ Natural enemies of vertebrate herbivores, Predators”, and 2.5.1. “Deterioration and/or shortage of food”, 2.5.1.9. “Wounding at aggressive territorial behavior”, 2.5.1.9.1. “Weakening” 2.5.1.9.1.1. “Mortality due to predators.”

In its habits, the musk-rat is close to those in the beaver, Castor spp., so that the former is called the small-beaver. Probably, the suggestions as to the complex of CESPPs of the mask-rat is true for the beavers.

In fens, when "the surface of the peat rises…it may be colonized by trees" (Godman and Payne, 1979, p. 333). Because water regime of such habitats is very unstable, they often are

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affected by stem borers. The protection against stem borers is proceeded by CESPPs 2.1.1.2.1.2. "Antibiosis to herbivores, Physiological (biochemical)."

4.8. Marches

The march is "a community dominated by rushes and similar plants…" (Godman and Payne, 1979, p. 333). The word "rushes" unites a number of species of diverse genera as follows: blunt-flowered rush, Juncus subnodulosus, beak rush, Rhynchospora spp., bog rush, Schoenus sp., mat rush, Scirpus validus, sea club rush, S. robustus, shore rush, S. americanus, flowering rush, Butomus umbellatus, spike rush, Heleocharis sp., scouring rush, Equisetum hiemale, smooth rush, E. laevigatum, stout rush, E. robustum, twig rush, Mariscus mariscoides and Cladium sp.

4.8. MarchesVertebrate herbivores

The above species are poisonous (Equisetum spp.), or with rigid and sharp sprouts – Cladium spp. (their Russian name is a "sword-grass"), or of low value as forage. In America, there is own the sword-grass, Scirpus americanus. The brushes Ledum palustre L. and Rhododendron luteum Sweet. are poisonous. These traits imply an operation of CESPPs 2.1.1.2.1.1.1. "Antibiosis to herbivores, structural, Permanent, and CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent" as to vertebtate herbivores. They are able to consume only tips of the grasses with juvenile tissues.

In Glyceria fluitans CESPPs 2.1.1.2.1.3. “Symbiosis with fungi toxic for herbivores” protects leaves from such herbivores (see 4.8. Phytopathogens).

4.8. MarchesPhytopathogens

In humid habitats of temperate climate, where fens and marches arise, there exist favorable conditions for activity of phytopathogens. The protection against them is proceeded probably by CESPPs 2.1.1.3.2.2.3. "Tolerance to phytopathogens, Compatibility and cooperation with natural enemies of parasites." In this context, it should cite K.F. Baker and R.J. Cooke (1974, p. 297): "Yeast are generally common …and may represent 1% of the wet weight of grass leaves in humid areas."

Moreover, the symbionts of the grasses provide their host-plants by the trait Antibiosis to vertebrate herbivores. This is CESPPs 2.1.1.2.1.3. “Symbiosis with fungi toxic for herbivores.” In fact, it was recorded heavy poisoning of calves, which fed by Glyceria fluitans with intensive affection by the leaf rust (Vil’ner, 1974, p. 299). The affection did not preclude thriving of the plants in a humid habitat. Being free from the rust, this species is known as a good forage (Ibid.).

4.9. Riverain formations4.9.1. Brushwood on the sandy soil along rivers

The dominants are presented by diverse species the willow, Salix spp.

4.9.1. Brushwood on the sandy soil along riversVertebrate herbivores

In winter, in these ecosystems are favorite for foraging of the hare, Lepus spp. As a means of self-protection, it serves CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues" in cooperation with CESPPs 2.2.2. "Natural enemies of herbivores", 2.2.2.2. "Predators." An operation of the Tolerance might be explained by accessibility of water and high activity of predators (in the past time).

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4.9.1. Brushwood on the sandy soil along riversInvertebrate herbivores

The SES is the same as in 4.1.3.e. Deciduous (Angiospermae) trees. It operates a composition of CESPPs 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues", 2.1.1.2.1.2. "Antibiosis to herbivores", 2.1.1.1.1."Nonpreference for herbivores", and 2.2.1. "Natural enemies of invertebrate herbivores."

4.9.2. Riverain forest

This formation arises on the rich soil along rivers. Here, it dominates the elder, Alnus spp., the poplar, Populus spp., and the willow Salix spp. The SES is the same as in 4.1.3.a Deciduous (Angiospermae) trees. The grassy cover is well developed. Its SES is close to that in 4.7. Fens.

4.9.3. Riverain grassy formation

This is vegetation on banks of streams and ponds. It is situated in habitats, which occupy a small area comparing with areas of surrounding steppes or forests. These circumstances determine the peculiarities in the composition of plants. It includes the species with extremely expressed traits of self-protection.

4.9.3.Riverain grassy formation,Vertebrate herbivores

This ecosystem attracts from vast areas vertebrate herbivores, which concentrate in it for watering. This has led to evolving of plant species with well-developed protection against the consumption by poisonous substances or the traits of low value for as forage.

They are Cicuta virosa L., Oenanthe aquatica Lam., O. fistulosa L., Calla palustris L., Arum maculatum L., Linaria vulgaris Mill., Pedicularius palustris L., Gratiola officinalis L., Triglochin palustris L., Glyceria aquatica Wahlb., Equisetum spp. (Vil’ner, 1974, pp. 36, 77, 116-121, 133, 183-185, 195-196).

S.A. Kott (1955, pp. 325, 341) noted "very poisonous" Ranunculus sceleratus L. and unpalatable for cattle Hierochloe odorata Whib. In the Mediterranian climate, in these habitats, it grows the poisonous oleander, Nerium oleander.

In all these cases, it operates of CESPPs 2.1.1.2.1.2.1. "Antibiosis to herbivores, Physiological (biochemical), Permanent" sometimes in cooperation with CESPPs 2.1.1.1.1. "Nonpreference to herbivores."

The reed-mace L., Typha angustifolia L., T. latifolia L., the calamus, Scirpus lacustris, the reed, Phragmites communis Trin. are common in such habitats. In the juvenile age (up to the spiking stage) they are palatable for cattle (Larin, 1964, p. 90). L.E. Rodin (1956a, p. 536) noted that the reed is consumed by hoofed animals also in the mature stage, when they nibble tips of reed’s stems. They are able to recover quickly, so that a pastering is possible over a season. This is the case of CESPPs 2.1.1.3.1.2."Tolerance to herbivores. Repair or compensation of losses of host-plant tissues."

4.9.4. Reed seasLocusts

This type of ecosystem is present in the lower reaches of rivers with plain relief, where flooding spreading on vast areas takes place in the most part of seasons. A number species of the reed, Phragmites spp. and calamus, Scirpus spp. are dominants in this ecosystem. They are accompanied by great many other plant species. This formation exerts the great impact on people, because it is a breeding ground of the Asiatic locust, Locusta migratoria L. Just from these areas, the locust makes its plundering raids.

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Possibilities of the locust to reach abundance are determined by amount of precipitation in higher parts of rivers. In years with the amount close to yearly average, the soil surface in the formation is inundated by water that limits existence of the locust by small plots inaccessible for the water. When the amount becomes lower, the soil surface dries up that allows the locust to reproduce on vast areas. A repeating of such a situation over a number of years in succession leads to outbreak of the locust. Such an explanation of arising of the locust’s outbreaks was offered by V.N. Shchegolev et al. (1949, pp. 320-321).

The breeding grounds of the locust are situated in these ecosystems within southern part of areas of temperate climate and in subtropic climate. The detailed characteristic of vegetation in such ecosystems in the Central Asia and southern Kazakhstan has been given by L.A. Sokolova and L.E. Rodin (1956a). These ecosystems florish in the lower reached of the rivers Syr Darya and Amu Darya. The areas of its ecosystems is characterized by the word "immence" and for them, it has been used the words "reed sea" (Ibid., p. 543). They are situated not only in the river’s valleys, but also spread on deltas of these rivers and great areas of creeks of the Aral Sea (Ibid., p. 541). The reeds Phragmites communis Trin. and Ph. isiaca (Del.) Kunth are salt-tolerant.

V.N. Shchegolev et al. (1949, pp. 320-321) reported that in USSR breeding grounds of the Locusta migratoria were the lower reaches of the above-mentioned rivers, the Terek, the Kuban, and others. O.P. Kryshtal (1959, pp. 142-143) added to this list the Seven River Lakes in the Central Asia, and in Ukraine the rivers Danube, Dnieper and Dnister.

The three latter rivers are less known as a source of the locust invasions. They are plain rivers. The water regime of the rivers, which are fed by mountain water is especially unstable that promotes to arising of outbreaks of the locust.

In the past, the same vegetation flourished in the lower reaches of the Nile. It was supposed to be that Moses led his people through a reed sea, rather than through the Red Sea. That was the way at a low tide. The chasing army of the Pharaoh was crushed by the rising tide. It seems, the source of the Plague of Locusts – the locust’s invasion was not too far.

On the level ESPPs 3.1. “Proper control”, the main CESPPs as to Locusta migratoria are 2.3."Routine weather suppression" that induces at spring flooding 2.3.10.1. "Mortality of larvae due to excessive moisture content in sites of hibernation", and 2.1.1.3.1.2. "Tolerance to herbivores, Repair or compensation of losses of host-plant tissues."

On the level ESPPs 3.3.“Late control”, it operates CESPPs 2.5. ‘Effects of crowding", 2.5.1. "Deterioration and/or shortage of food", 2.5.1.4. "Emigration in the adult stage in advance of food deterioration and/or exhaust" and the effect 2.5.1.4.1. "Mortality due to diverse factors."

Other insect herbivores on the Ph. communis in lower reaches of the Rivers Dnieper were studied by V.A. Lozinsky and G. P. Oksyutich (1967). Over two-years studies, the following species occurred to be in the density, which might be harmful for the host-plant: Platycephala planifuens F. (Diptera, family Chloropielae), Auchanara geminipuncta Hw.(Lepidoptera, Noctuidae), Phragmataecia costaneae Hb.(Lepidoptera, family Cossidae), Chilo phragmitellus Hb., Chilo cicatricellus Hb. (Lepidoptera, family Pyralidae), Cosmotriche popatoria L. (Lepidoptera, family Lasiocampidae), Hyalopterus pruni F. (Aphididae).

The scholars noted prevalence stem boring insect species.Mortality of the reed due to affection of above species was not recorded. It took place

decrease of mass of affected plants and content of cellulose in them. It was found out numerous species of natural enemies of the pests– parasites, predators and pathogens. Density of of the pests was greater in areas disturbed by humans, where stem density was low and water regime was unproper.

It is probable that in such conditions with abundant watering, ESPPS of the level 3.1. “Proper control” is maintained by CESPPs 2.1.1.3.1.2."Tolerance to herbivores. Repair or compensation of losses of host-plant tissues” in cooperation with 2.2.1. "Natural enemies of invertebrate herbivores" and 2.1.1.3.1.3. “Indifference to losses of host-plant tissues.”

The advanced Tolerance allows some ecosystems with dominance of the reed to exist on the level ESPPs 3.3. “Late control” continually. Such a case was offered by J.H. Mook and J.van der

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Toorn (1985), who revealed that heavy damage of the reed Phragmites australis (communis) by larvae of stem boring moth Archanara geminipuncta induced developing thinned shoots, which were unfit for inhabiting of the larvae. In a result, every third year the moth disappeared. This is the case of operation of CESPPs 2.5.1.2. Raising of secondary structural antibiosis, 2.5.1.2.1. Exuding of protective substances on a surface of buds or developing of protective barriers in affected tissues, that caused 2.5.1.2.1.1. Starvation.

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STABILITY OF TERRESTRIAL ECOSYSTEMS AS TO PEST …€¦ · Web view. [email protected] 14_Axiom4-1.doc. PART II. SUBSTANTIATION of the AXIOMS PROPOSED in the PART I. AXIOM 4(1) STRUCTURE