REGULATED RIVERS: RESEARCH & MANAGEMENT, VOL. 13, 199–202 (1997)

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HYDROLOGY AND HYDROCHEMISTRY OFBRITISH WETLANDS, edited by J. Hughes andL. Heathwaite. John Wiley & Sons, Chichester,1995. No. of pages: 486. Price: £60.00 ISBN 0-471-95759-3.

Although the literature on wetlands has expandedenormously in recent years, this book performs avaluable function in drawing attention to work thathas been undertaken specifically within British wet-lands, illustrating how the applied aspects of wetlandsresearch and the need to understand the significanceof wetland processes for nitrate and phosphorusdynamics have driven research. The book has itsorigins in a meeting at the Institute of BritishGeographers Conference in January 1993, withadditional invited contributions, and although it hastaken over two years to come to press there is muchof current interest. The book comprises a total of 25chapters which form three sections on hydrology,hydrochemistry and ecology and management. Thesections have introductory chapters which aim to putthe British research into an international context;although given the enormous global increase inwetlands research this is difficult and is only partiallysuccessful. For example, there is very limitedreference to hydrological studies in American wet-lands, or discussion of why British wetlands shouldbe regarded as unique. However, the last chapter isespecially useful as it gives a summary of researchneeds for wetlands identified by the Terrestrial andFreshwater Sciences Committee of the NaturalEnvironment Research Council. This chapter pro-vides the context for much of the research describedin the whole book, it emphasizes our current lack ofunderstanding of physical processes in wetlands, andalso the wide-ranging benefits and values that havebeen attributed to wetlands.

Hydrology is frequently described as the mainfactor determining wetland characteristics: theirecology and geomorphology (Mitsch and Gosselink,1993). These concepts are reinforced in several

chapters that outline the development of waterbudgets for wetlands. However, as outlined in thefirst two chapters by Hughes and Heathwaite, there isa considerable variety in British wetlands whetherthey are described as fens and bogs, wet heath ormarshes and meadow. These wetland types have beenstudied to differing extents in this country asillustrated by the chapters in the hydrological section.Burt describes the hydrology of headwater wetlands,while a groundwater focus is provided by Lloyd andTellam who review their work on soligenous wet-lands, mainly in East Anglia. Similarly, Bromley andRobinson illustrate the potential of a numerical modelto determine the effects of hydrological managementon a raised bog. The area of greatest difficulty withwetlands is determining the ecological consequencesof hydrological change, and this is considered byWheeler and Shaw. Although vegetation records havethe potential to cover periods of hydrological change,this is frequently difficult as past records mainlyinclude occurrence, and not abundance, of individualspecies. Vegetation is also significant in accountingfor variations in wetland evapotranspiration, whichmight be expected to be the dominant term in mostwetland water budgets, while to understand thelinkage between hydrology and ecology there is aneed for more studies of unsaturated water content.Baird gives a thoughtful analysis of current wetlandstudies and considers that the emphasis upon budget-ary analysis and measuring water table fluctuationshas detracted from greater physical understanding ofwetland processes, and in particular the oftenunquestioned application of Darcian principles todescribe water flow through wetland substrates. Inthis respect, the larger focus described by Kirkby andothers is potentially very useful, as it links hydro-logical and ecological processes and successfullyraises the scale from site-specific studies. However, Iwould have welcomed more information on thederivation of some equations, and Equation (6.4) inparticular [a� (i0� dq/dx)i1].

The hydrochemistry section concentrates uponnitrogen and phosphorus dynamics, with most

# 1997 by John Wiley & Sons, Ltd.

emphasis on riparian wetlands as buffer zones, andlargely consisting of work undertaken in south-westEngland. The introductory chapter by Ross, gives anextended overview of chemical processes withinwetlands. This successfully identifies the contributionof work overseas, but is rather long and there is somerepetition with introductory sections in other chap-ters. Much of the hydrochemistry section is con-cerned with understanding the role of wetlands innitrogen and phosphorus cycling, which is an area ofcurrent interest given the potential of riparian bufferzones to assimilate nutrients. Accordingly, the wet-land focus is dominated by lowland wetlands: Bakerand Maltby examine nitrate processes and Russelland Maltby consider phosphorus dynamics in flood-plains in south-west England. Similarly, Gaffney andRoss, and Ross and others look at solute processes inthe Somerset Moors area, and illustrate the benefits ofcombining field experimentation and laboratoryanalysis to understand the hydrochemistry. Thesignificance of laboratory work is further illustratedby Skeffington and others who describe work toidentify a critical load for dystrophic peat. The effectof differences in water source and hence hydro-chemistry on vegetation is illustrated by Proctor whodescribes the wetland system at Malham Tarn. WhileButcher and others describe another area of concernand the management protocols devised to controlwater colour changes induced by peat decompositionin a Pennine catchment.

The challenge in wetland studies is to apply thisunderstanding of physical processes to the ecologyand management of wetlands, which requires anappreciation of the effects of hydrology on flora andfauna. These questions are considered in differentways in Section III on ‘Ecology and Management’.The problem is introduced by Hughes and Johneswho outline how hydrology governs both the input oforganic matter to a wetland and also the internalproduction of energy. Maltby and others provide afurther discussion on wetland hydrochemistry, byexploring how catchment management influences theprocess of denitrification, and how soil conditions canaffect the wetlands role as a nitrogen sink. Differentmanagement perspectives for lowland raised miresare described separately by Money and Heathwaitefor Thorne Moors in Yorkshire, and exemplify thedifficulty in successfully integrating ecology andhydrology. A more ecological focus is provided byNewall and Hughes who consider the ability ofmacrophytes to create distinctive hydraulic environ-

ments within wetlands. In many areas such processeswithin wetlands are limited by recent land manage-ment as illustrated by Boothby and others for pondsin north-west England where land reclamation has ledto a considerable loss of habitat. In this context, thereis an urgent need for the development of wetlandinventories in Britain, possibly having a similar formto the National Wetlands Inventory of the UnitedStates, to acquire accurate information on wetlandloss nationally (e.g. NRC, 1995). There is a generallack of data characterizing wetlands at an appropriatescale, so that remote sensing is likely to be ofincreasing importance. Gilvear and Watson describethe potential of this technique for examining thehydrology of the extensive Insh Marshes, an area offloodplain wetland beside the River Spey. Theacquisition of data at this scale is essential for thesuccessful recreation of wetlands as described byArmstrong and others, who look at wetland restora-tion at three scales: at Marsh Gibbon beside the RiverRay, at Elmley Marsh and at Leadwell Meadows.These wetlands have been managed under centralgovernment initiatives, by the Royal Society for theProtection of Birds and by a local council, respec-tively, illustrating the variety of bodies involved withwetland management and the differences in availableresources.

The editors are to be congratulated on bringingtogether the different themes discussed in individualchapters. While there is some repetition of basicconcepts, different derivations of wetlands’ waterbudgets and several descriptions of the diplotelmicmodel of mire systems, the book has an overallcohesion, and emphasizes the diversity of approachesadopted by British wetland studies. The diagramshave generally been produced to a high standardthroughout, although the generalized wetland waterbudget in Figure 2.1 is unattributed to Mitsch andGosselink (1993; their Figure 4-5), and the ground-water influx arrow is misdirected. Hydraulic con-ductivity is also given in different units within thebook. On a different note, in the hydrological section,more discussion of the significance and variability ofwater yield would have been useful. This is one of thekey hydrological properties of wetlands and does notappear in the index, although the property ofwetlands to store water is frequently cited as one oftheir key values. Similarly, the hydrological chaptersdemonstrate the lack of studies devoted to wetlandevapotranspiration. Frequently, evapotranspirationhas been estimated as the residual term of the water

200 BOOK REVIEWS

# 1997 by John Wiley & Sons, Ltd. Regul. Rivers.Vol. 13, 199–202 (1997)

balance, or from MORECS, and although there areproblems with evapotranspiration measurements as-sociated with the oasis effect and the small size ofmost wetlands, the lack of accurate evapotranspira-tion data needs to be addressed very soon.

In conclusion,Hydrology and Hydrochemistry ofBritish Wetlandsgives a useful representation ofwork currently underway in this country. Thecollection of chapters is therefore an invaluableaddition to previous books looking at British wet-lands such as Gilman (1994) and Wheeleret al.(1995), and includes a good combination of process-based field studies with modelling approaches anddiscussion of hydrological and ecological interaction.Although the emphasis of individual chapters islargely upon empirical work, the potential fordevelopment of new theoretical models of wetlandsystems is evident. However, it would have beenuseful to have a description of the current status ofthe British wetland resource. Data on wetlandoccurrence are difficult to acquire and emphasizethe importance of wetland definition, classificationand ultimately the development of wetland inven-tories. However, the benefits have been recognizedelsewhere (NRC, 1995), and hopefully will beapplied to Britain in the near future. A further pointthat is worth emphasizing is the growing interdisci-plinary basis of wetland studies. This comes across

well in the book from a hydrological and ecologicalperspective, but it is also significant for archaeology,as recognized by Coles (1995) who utilizes materialfrom different disciplines to extract material relevantto wetland management for archaeological purposes.The applied nature of wetland work such as this islikely to become increasingly evident in sustainingwetlands research and in improving our capability ofmanaging the quantity and quality of water fluxes forisolated wetland sites, and relating to the changes inthe wetland flora and fauna.

REFERENCES

Coles, B. 1995.Wetland Management: a Survey for EnglishHeritage.WARP Occasional Paper 9, 126pp.

Gilman, K. 1994. Hydrology and Wetland Conservation.JohnWiley, Chichester.

Mitsch, W. J. and Gosselink, J. G. 1993.Wetlands, 2nd edition.Van Nostrand Reinhold, 722pp.

NRC (National Research Council), 1995.Wetlands Characteristicsand Boundaries.National Academy Press, Washington, D.C.308pp.

Wheeler, B. D., Shaw, S. C. Fojt, W. J. and Robertson, R. A. 1995.Restoration of Temperate Wetlands.John Wiley, Chichester.562pp.

CHRIS BRADLEYSchool of Geography,

University of Birmingham,Birmingham, B15 2TT, UK

REGULATED RIVERS: RESEARCH & MANAGEMENT, VOL. 13, 199–202 (1997)

CONSERVATION OF ENDANGERED FRESH-WATER FISH IN EUROPE, edited by A. Kirch-hofer and D. Hefti, Birkha¨user Verlag, Basel,Switzerland, 1996. No. of pages: 341. ISBN (hard)3-7643-5321-X.

The fish fauna of European fresh waters has sufferedthe consequences of increased pollution and loss offloodplain habitat, as indicated by the decline in theabundance and geographical distribution of manyspecies. This problem is continuing, despite ourgreater awareness of the environmental needs ofmany fish species, and in spite of the initiative of theWorld Conservation Strategy, launched in 1980.Attempts to reinforce stock levels, either for speciesdeclining in number or to enhance species of

economic importance, has often exacerbated theproblem through concomitant loss of intraspecificgenetic diversity.

The global extent of the problem was highlightedin 1990 at the FSBI symposium at Lancaster, UK onthe Biology and Conservation of Rare Fish.In 1994,an international meeting at the University of Bern,Switzerland, to discuss theConservation ofEndangered Freshwater Fish in Europefocusedattention on the problems emanating from a muchsmaller geographical region. The papers presented atthis meeting form the basis of this excellentlyproduced book; although the title of the book issomewhat misleading as only 15 countries wererepresented at the meeting, and none fromScandinavia.

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# 1997 by John Wiley & Sons, Ltd. Regul. Rivers.Vol. 13, 199–202 (1997)