Matarial Cycles and Physical Condition

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MATARIAL CYCLES AND PHYSICAL CONDITION

OF EXISTENCES

PAPER Arranged in partial fulfillment Basic Ecology

that guided by Prof. Dr. Hj. Mimien Henie Irawati, M.S.

and Dr. Fatchur Rohman, M.Si.

By:

1. Ndzani Latifatur Rofi¶ah (100341400702)

2. HikmahMaulidiah (100341400688)3. HamimTohariMahfudhillah (100341400686)

The Learning University

UNIVERSITY OF MALANG

FACULTY OF MATHEMATICS AND NATURAL SCIENCES

DEPARTMENT OF BIOLOGY

JANUARY 2012



Material Cycle and Physical Condition of Existence |2

A. Background

The human daily activity such as using detergent, using fossil fuel, using

some fertilizer, using air conditioned (AC), and so on. Without exception the use

of natural resources is accompanied by the production of unwanted waste and it

can influent to the major biogeochemical cycle, such as carbon cycle, nitrogen,

sulfur, and phosphorus. The uncontrolled usage can also disturb and damage the

ecosystem, for example the overuse of fossil fuel can increase the atmospheric

carbon dioxide that may cause warming of global climate, use of phosphorus

fertilizer may result nutrient pollution of river, lake, and sea.

In order to analyze the long-term impact we must understood the cycle of

biogeochemical cycle. Only after this has been done we can determine the best

way to reduce the effect or modifies these cycle.

a. Problems Formula

1. How are the processes of hydrological cycle in the world and what

it¶s importance?

2. How are the processes of nitrogen cycle in the world?

3. How are the processes of phosphorus cycle in the world?

4. How are the processes of sulfur cycle in the world?

5. What is ozone? And what are the functions?

6. How are the processes of global carbon cycle?

7. How is the nutrient cycling in nutrient-poor soils?

8. How are the processes of recycling pathways?

9. How are the processes of sediment cycle?

b. Objectives

1. To know the processes of hydrological cycle in the world and it¶s

importance.

2. To know the processes of nitrogen cycle in the world.

3. To know the processes of phosphorus cycle in the world.

4. To know the processes of sulfur cycle in the world.

5. To know the ozone and the functions.




6. To know the processes of global carbon cycle.

7. To know the nutrient cycling in nutrient-poor soils.

8. To know the processes of recycling pathways.

9. To know the processes of sediment cycle.

B. The Hydrological Cycle

There are two phase of hydrological cycle, the uphill or upstream and

downstream phase. The upstream phase is driven by solar energy that makes water

in the sea (the largest), land, pond, plant, and organism evaporate. The water

vapor that accumulated in the atmosphere made up clouds and return as rainfall

(Odum, E.P., 1989:109)

Figure 1. Hydrological cycle (Source: Campbell, 2008:1232)

The rainfall is very important for the land ecosystem and biomes, for

example: tropical forest, desert, savanna, and may be for the farmer in the




mountain. From the rainfall human can also use it as hydropower. One estimate is

that 20% of annual rainfall on the land runs off to the sea, and 80% recharges the

surface and groundwater reservoirs. The groundwater is being used by humans for

irrigation, industry, and drinking water. But nowdays, most of human increase

runoff and decrease infiltration into the soil by paving, ditching, draining swaps,

compacting soil, and cutting down forest. If human continuously do this, the water

will be gone.

C. The Nitrogen Cycle

Nitogen is an essential constituent of living biomass, primarily as protein and

amino acid, and change in carbon cycling. Nitrogen compound in the atmosphere

originate from natural biological activity for example, denitrification by bacteria,volcanoes, lighting, combustion of fossil fuels, and waste products of domestic

animal (Soutwick, 1985:74).

Figure 2. Diagram of Nitrogen Cycle (Source: Solomon, 2008:1174)




Figure 3. Nitrogen cycle in land ecosystem (Source: Starr, 2011:718)

The amount of both nitrogen oxides and ammonia in the atmosphere are

significantly influence combustion of fossil fuels and by waste from domestic

animal feed. Nitrogen oxides react in the atmosphere to form acidic compound

that contribute to acidic wet and dry deposition (Soutwick, 1985:74).

The amount of nitrogen (as nitrogen oxides and nitrate) formed by the

burning of coal and petroleum, and also by fertilizer is equal to about one half of

that produced naturally by the biosphere.

D. The Phosphorus Cycle

Phosphorus exist in the atmosphere as aerosol (does not have gaseous phase).

It can originate from crustal weathering, the oceans, and human activities such as

usage of detergent, sewage processing, and phosphorus fertilizer on agricultural

land. Phosphorus is eventually removed via air or water transport to the ocean,

then it is taken up by organisms and eventually incorporated into bottom

sediments. After million years, phosphorus in plant and fish remain is converted

into phosphate minerals (Soutwick, 1985:75).




Figure 4. Diagram of Phosphate Cycle (Source: Campbell,2008:1233)

E. The Sulfur Cycle

The sulfur cycle is the collection of processes by which sulfur moves to and

from minerals (including the waterways) and living systems. Such

biogeochemical cycles are important in geology because they affect many

minerals. Biogeochemical cycles are also important for life because sulfur is an

essential element, being a constituent of many proteins and cofactors (Anonym1,

2011).

Steps of the sulfur cycle are:

y Mineralization of organic sulfur into inorganic forms, such as hydrogen

sulfide (H2S), elemental sulfur, as well as sulfide minerals.

y Oxidation of hydrogen sulfide, sulfide, and elemental sulfur (S) to sulfate

(SO42±

).

y Reduction of sulfate to sulfide.




y Incorporation sulfide into organic compounds (including metal-containing

derivatives). (Anonym1, 2011)

Atmospheric sulfur is derived from a number of sources, including

volcanoes, the combustion of fossil fuels, and microorganism activity in

tidal flats and the water-logged soils of swamps and bogs. Sulfur is emitted

into the atmosphere from natural and anthropogenic (manmade)

sources, but many of the effects of emissions are identical.

In the atmosphere, sulfur gases that have been converted to sulfuric acid

are conveyed to the Earth's surface by precipitation or dry deposition. The

rapid removal of this el ement from the at mosphere restricts the transport of

anthropogenic emissions to short distances. Unlike fossil-fuel-produced

CO2, which has a global distribution, sulfur originating from coal and petroleum only disperses to a maximum of a few thousand kilometers

(Southwick, 1985).

Figure 5. Diagram of Sulfur Cycle

The sulfur (S) cycle, illustrates many of the main features of material cycling

1. A large reservoir in sediments a nd a smaller reservoir in the

atmosphere;

2. The key role in the rapidly fluctuating pool (the center "wheel") is




played by specialized microorganisms that function like a relay team, each

carrying out a particular chemical transformation;

3. The upward movement of a gaseous phase, hydrogen sulfide (H2S),

which result in a microbial recovery of sulfur otherwise "lost" in the deep

sediments;

4. The interaction of geochemical, meteorological and biological processes,

and the interdependence of air, water, and soil in maintaining the cycle at the

global level; and

5. When iron sulfides are formed in the sediments, phosphorus is converted

from insoluble to soluble form, as shown by the "phosphorus release"

arrow, and thus enters the pool available to living organisms. Recovery of

phosphorus as a part of the sulfur cycle is most pronounced in theanaerobic (without oxygen) sediments of wetlands, which are also

important sites for the recycling of nitrogen and carbon (Odum, 1989).

F. Ozone, a ³Chemical Weed´

A weed is sometimes defined as a plant in the wrong place, that is ,a

generally useful or harmless plant that insists on growing where we don¶t want it

(such as in the garden). Resources which are essential in cycles can cause trouble

when their amounts are increased or when they turn up in the wrong place as

a result of human activities. Ozone (O3) is a prime example of something

which we cannot live without, yet when in the wrong place is costly and

dangerous "chemical weed." (Odum, 1989).

Ozon is formed naturally in the stratosphere as incoming solar radiation

interacts with oxygen. The ozone layer in the upper atmosphere shields us from

deadly ultraviolet radiation, and its formation early in the earth's history enabled

terrestrial life to evolve to its present advanced state. Certain air pollutants,

notably chlorofluorocarbons (Cohn 1987) from aerosol cans and emissions from

high-flying jet aircraft, can break down this life-sustaining shield. Such a prospect

is so frightening that limits on chlorofluorocarbon production were set in

1970, resulting in a 17 percent reduction in the production of these gases. Some

industries are voluntarily suspending manufacture. However, these limited




reductions in the United States are not enough to halt the threat to the global

shield, which now shows signs of Chinning, especially in the Antarctic (Bowman

1988).

At the same time that we strive to maintain it in its proper place, ozone in the

lower atmosphere is becoming a major photochemical oxidant pollutant at

ground level. A recent experimental study showed that ozone, in the

concentrations of 0.02-0.14 ppm (parts per million) that now exist in areas

far removed from large cities, reduced photosynthesis in all species of crops

and trees tested (Reich and Amundson 1985), suggesting that ground-level ozone

may be a greater threat to us and our life-support system than acid rain. Or, as

we might expect, there could be a synergism between the two. Kneese

(1984), in a study of the economic benefits of clean air and water, calculatedthat even a very small reduction of 0.01 ppm in ground-level ozone

concentrat ion would result in a million fewer cases of chronic respiratory

disease in the work force, yielding a benefit to business of greater than a billion

dollars a year (Odum, 1989).

G. The Global Carbon Cycle

The carbon cycle is the biogeochemical cycle by which carbon is

exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and

atmosphere of the Earth. It is one of the most important cycles of the earth and

allows for carbon to be recycled and reused throughout the biosphere and all of its

organisms (Anonym2, 2012).

The global carbon cycle can be divided into two categories: the

geological, which operates over large time scales (millions of years), and the

biological - physical, which operates at shorter time scales (days to thousands of

years) and as humans we meddle with both categories (Anonym3, 2011).

The global carbon cycle refers to the movements of carbon, as it exchanges

between reservoirs (sinks), and occurs because of various chemical, physical,

geological, and biological processes. The ocean contains the largest active pool

of carbon near the surface of the Earth, but the deep ocean part of this pool does

not rapidly exchange with the atmosphere. Below in the diagram, you can get




some idea where and how carbon is stored in the whole Earth system. The global

carbon cycle is usually thought to have four major carbon sinks interconnected by

pathways of exchange. These sinks are:

y the atmosphere,

y the terrestrial biosphere (which usually includes freshwater systems and

non-living organic material, such as soil carbon),

y the oceans (which includes dissolved inorganic carbon and living and non-

living marine biota),

y and the sediments (which includes fossil fuels ).

Carbon exists in the Earth's atmosphere primarily as the gas carbon dioxide

(CO2). Although it is a very small part of the atmosphere overall (approximately

0.04% and rising fast), it plays an important role in supporting life. Other gasescontaining carbon in the atmosphere are methane and chlorofluorocarbons (the

latter is one we introduced and are still adding to). These are all greenhouse gases

whose concentration in the atmosphere are increasing, and contributing to the ri

sing average global surface temperature (Anonym3, 2011).

The annual movements of carbon, the carbon exchanges between reservoirs,

occur because of various chemical, physical, geological, and biological processes.

The ocean contains the largest active pool of carbon near the surface of the Earth,

but the deep ocean part of this pool does not rapidly exchange with the

atmosphere in the absence of an external influence, such as a black smoker or an

uncontrolled deep-water oil well leak.

The global carbon budget is the balance of the exchanges (incomes and losses)

of carbon between the carbon reservoirs or between one specific loop (e.g.,

atmosphere biosphere) of the carbon cycle. An examination of the carbon

budget of a pool or reservoir can provide information about whether the pool or

reservoir is functioning as a source or sink for carbon dioxide (Anonym2, 2012).




Figure 6. Diagram of Carbon Cycle

Global Carbon Cycle - Sinks and Storage

Carbon is taken up from Earth's system in several ways:

1. When the sun is shining, plants perform photosynthesis to convert carbon

dioxide into carbohydrates, releasing oxygen in the process. Deforestation

and land clearing pose serious problems to the carbon cycle, and obliterating

this sink means more carbon is forced into the atmosphere.

2. At the surface of the oceans towards the poles, seawater becomes cooler and

CO2 is more soluble. Cold ocean temperatures favour the uptake of carbon

dioxide from the atmosphere whereas warm temperatures can cause the ocean

surface to release carbon dioxide. With seas warming this means CO2 is not

so easily absorbed, and remains in the atmosphere. This is coupled to the

ocean's thermohaline circulation which transports dense surface water into the

ocean's interior. During times when photosynthesis exceeded respiration,

organic matter slowly built up over millions of years to form coal and oil

deposits. All of these biologically mediated processes represent a removal of




carbon dioxide from the atmosphere and storage of carbon in geologic

sediments.

3. In upper ocean areas of high productivity, organisms form tissue containing

carbon, and some also form carbonate shells or other hard body parts. Apart

from trees in forests, phytoplankton in the Earth's oceans are very important

organisms that soak up carbon. The seas contain around 36000 gigatonnes of

carbon, and again and in warmer seas, organisms cannot produce carbonate

shells at the same rate, and increasingly acidic seas dissolve shells, or make it

difficult to create shelly material. This means of course that carbon dioxide is

not being taken up as quickly through this process and more carbon remains

in the atmosphere, propelling global warming.

4. As shelled organisms die, bits and pieces of the shells fall to the bottom of theoceans and accumulate as sediments. Only small amounts of residual carbon

from plankton settle out to the ocean bottom but over long periods of time

these represent a significant removal of carbon from the atmosphere

(Anonym3, 2011).

Global Carbon Cycle - Sources

Carbon can be released back into the system in many different ways:

1. Through the respiration performed by plants and animals.

2. Through the decay of animal and plant matter. Fungi and bacteria break down

the carbon compounds in dead animals and plants and convert the carbon to

carbon dioxide if oxygen is present, or methane if not. The melting

permafrost is releasing large amounts of methane, which contributes to global

warming at a rate 21 more times than carbon dioxide.

3. Through combustion of biomass which oxidizes the carbon it contains,

producing carbon dioxide (as well as other things, like smoke). Burning fossil

fuels such as coal, petroleum products, and natural gas releases millions of

tonnes of carbon that has been stored in the geosphere for millions of years.

Fires also consume biomass and organic matter to produce carbon dioxide

(along with methane, carbon monoxide, smoke), and the vegetation that is

killed but not consumed by the fire decomposes over time adding further




carbon dioxide to the atmosphere. Wildfires and forest fires are likely to

increase as land masses dry out with higher rates of evaporation.

4. Production of cement. A component, lime, is produced by heating limestone,

which produces a substantial amount of carbon dioxide, and impacting upon

the global carbon cycle.

5. At the surface of the oceans where the water becomes warmer, dissolved

carbon dioxide is released back into the atmosphere.

6. Volcanic eruptions and metamorphism are part of the global carbon cycle and

release gases into the atmosphere. These gases include water vapour, carbon

dioxide and sulphur dioxide (Anonym3, 2011).

H. Nutrient Cycling in Nutrient-poor SoilsOne of the myths about the tropic is that the soils there are fertile and

capable of feeding if we would just remove the forests and plant crops. There are,

of course, areas of ferule soil in the warmer climates, but soils in huge arm, such

as the tropical rain forests of the Amazon basin, are quite poor compared with

areas such as the prairie soils of Iowa. Luxuriant forests ate able to persist in the

Amazon because of efficient biotic recycling mechanisms that keep vital nutrients

such as phosphorus and nitrogen circulating within the biomass. In such forests,

less than half of the available pool of nutrients is in the soil, as compared with

more than 90 percent in European or eastern North American forests. When

vegetation is removed from temperate forests or prairies for agricultural purposes,

the sods retain their nutrients and structure. They can be conventionally farmed

for many years, which involves plowing one or more times a year, planting short-

season annual, plants, and applying large amounts of quick-release inorganic

fertilizers. During the winter, freezing temperatures help hold in nutrients and

combat pests and diseases. In the tropics, on the other hand, forest removal takes

away the land's ability to hold and recycle nutrients (as well as to combat pests) in

the face of high year-round temperatures and periods of-leaching rainfall. The thin

tropical soils lack organic and biotic holding,, mechanisms, so any nutrients left in

them are quickly drained away. Crop production declines rapidly (maybe after




only 2 to 3 years), and the land is abandoned, creating the pattern of shifting

agriculture so common in the tropics (Odum, 1989).

y Essential Plant Nutrients

There are at least 16 essential chemical elements for plant growth. Carbon,hydrogen, and oxygen, obtained in large amounts from air and water, make up the

bulk of plant dry matter in the products of photosynthesis, but usually are not

included as ³nutrient´ elements. Nitrogen (N), phosphorus (P), potassium (K),

calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), zinc (Zn),

copper (Cu), boron (B), molybdenum (Mo), and chlorine (Cl) are obtained from

the soil and required by all plants. Sodium, silicon, and nickel are essential

elements for some plant species and, although not required, have positive or

beneficial effects on the growth of other species. Cobalt is essential for nitrogen

fixation by legumes. Additional elements, such as selenium and iodine, are not

required by plants, but can be important in plant nutrition because they are

essential nutrients for humans and other animals that consume plants.

All essential nutrients are equally important for healthy plant growth, but

there are large differences in the amounts required. N, P, and K are primary

macronutrients with crop requirements generally in the range of 50 to 150

lbs/acre. Ca, Mg, and S are secondary macronutrients, required in amounts of

about 10 to 50 lbs/acre. Micronutrient requirements (Fe, Mn, Zn, Cu, B, Mo, and

Cl) are generally less than 1 lb/acre (Peter M. Bierman, 2011).

y Sources of Plant Nutrients in the Soil

Plants obtain mineral nutrients through root uptake from the soil solution.

Sources of these soluble nutrients in soil include:

1. Decomposition of plant residues, animal remains, and soil microorganisms

2. Weathering of soil minerals

3. Fertilizer applications

4. Manures, composts, biosolids (sewage sludge), kelp (seaweed), and other

organic amendments such as food processing by products

5. N-fixation by legumes

6. Ground rock products including lime, rock phosphate, and greensand

7. Inorganic industrial byproducts such as wood ash or coal ash




8. Atmospheric deposition, such as N and S from acid rain or N-fixation by

lightning discharges

9. Deposition of nutrient-rich sediment from erosion and flooding

Among biotic devices that aid in keeping nutrients recycling within the

living biomass in tropical forests are the following:

1. Root mats consisting of many fine feeders penetrating the surface little

quickly recover nutrients from fallen leaves before they can be leached

away. Root mats apparently also inhibit the activities of denitrifying

bacteria, thus blocking the loss of nitrogen to the air. Solve tropical trees

even have "upwardly mobile roots" that grow upward on the tree trunks

(instead of downward into the soil as do normal roots) and are thus able to

absorb nutrients from rainwater flowing down the stern (Sanford 1987)2. Mycorrhizal fungi, symbiotic microorganisms associated with root

systems, act as nutrient traps, greatly facilitating the recovery of nu-trients

and their retention within the biomass. (This symbiosis between higher

plant and microorganism for mutual benefit is widespread on poor soils in

the temperate zone as well.

3. Evergreen leaves with thick, waxy cuticles and thick bark retard loss of

water and nutrients and also resist herbivores and parasites.

4. Algae and lichens that cover the surfaces of many leaves scavenge

nutrients from rainfall and fix nitrogen from the air.

(For more on nutrient cycling in tropical forests, sec Jordan 1982, 1985.)

This brief account, of course, oversimplifies complex situations, but it

shows why sites in the tropics that support luxurious forests yield so poorly under

northern-style crop management. It is evident that a different type of agriculture

needs to be designed for the tropics one involving reduced soil disturbance (less

plowing), more perennial plants that use C4 photosynthesis and perhaps

mycorrhizae, more multiple cropping, and more use of legumes and other

nitrogen-fixers (Odum, 1989).

y Soil Composition

Over two-thirds of the world's rainforests, and three-fourths of the

Amazonian rainforest can be considered "wet-deserts" in that they grow on red




and yellow clay-like laterite soils which are acidic and low in nutrients. Many

tropical forest soils are very old and impoverished, especially in regions²like the

Amazon basin, where there has been no recent volcanic activity to bring up new

nutrients. Amazonian soils are so weathered that they are largely devoid of

minerals like phosphorus, potassium, calcium, and magnesium, which come from

"rock" sources, but are rich with aluminum oxide and iron oxide, which give

tropical soils their distinctive reddish or yellowish coloration and are toxic in high

amounts. Under such conditions, one wonders how these poor soils can appear to

support such vigorous growth.

Rainforests are tremendously vegetated. Early European settlers in the

tropics were convinced (and even assured by scientists at the time) that the

lushness of the "jungle" was due to the rich soils, so they cut down large patchesof forest to create croplands. The cleared land supported vigorous agricultural

growth, but only for one to four years, when mysteriously, plant growth declined

to a point where copious amounts of fertilizer were required for any growth.

Settlers wondered why their crops perished and how such poor soil could support

the luxuriant growth of tropical rainforest. The answer lies in the rapid nutrient

cycling in the rainforest (Rhett A. Butler, 2011).

y Nutrient Cycling

The colonial settlers did not realize that they were dealing with an entirely

different ecosystem from their temperate forests where most of the nutrients exist

in the soil. In the rainforest, most of the carbon and essential nutrients are locked

up in the living vegetation, dead wood, and decaying leaves. As organic material

decays, it is recycled so quickly that few nutrients ever reach the soil, leaving it

nearly sterile.

Decaying matter (dead wood and leaf litter) is processed so efficiently

because of the abundance of decomposers including bacteria, fungi, and termites.

These organisms take up nutrients, which are released as wastes when organisms

die. Virtually all organic matter is rapidly processed, even fecal matter and

perspiration. It is only a matter of minutes, in many rainforests, before dung is

discovered and utilized by various insects. Excrement can be covered with

brightly colored butterflies, beetles, and flies, while dung beetles feverishly roll




portions of the waste into balls for use later as larval food. Insects are not only

attracted to dung for the energy value, but often for the presence of nutrients like

calcium salts. Human sweat is a treasure for several species of butterflies, which

gather on the necks and hats of tourists, and for annoying sweat bees, which can

cover seemingly every inch of exposed skin in some forests (Rhett A. Butler,

2011).

As vegetation dies, the nutrients are rapidly broken down and almost

immediately returned to the system as they are taken up by living plants. Uptake

of nutrients by plant roots is facilitated by a unique relationship between the roots

and a fungi, mycorrhizae. The mycorrhizae attach to plant roots and are

specialized to increase the efficiency of nutrient uptake nutrient from the soil. In

return, plants provide the fungi with sugars and shelter among their roots. Studieshave also shown that mycorrhizae can help a tree resist drought and disease (Rhett

A. Butler, 2011).

Goals of effective nutrient management are to provide adequate plant

nutrients for optimum growth and high-quality harvested products, while at the

same time restricting nutrient movement out of the plant-root zone and into the

off-farm environment. Biological processes control nutrient cycling and influence

many other aspects of soil fertility. Knowledge of these processes helps farmers

make informed management decisions about their crop and livestock systems.

How these decisions affect soil biology, especially microbial activity, root growth,

and organic matter, are key factors in efficient nutrient management. Managing

soil organic matter and biological nutrient flows is complex, because crop

residues, manures, composts, and other organic nutrient sources are variable in

composition, release nutrients in different ways, and their nutrient cycling is

strongly affected by environmental conditions.

Chemical and physical processes in soil largely control mineral solubility,

cation exchange, solution pH, and binding to soil particle surfaces . Knowledge of

soil chemistry makes it possible to formulate fertilizers that supply readily

available plant nutrients. Management of inorganic nutrient sources is simpler

than organic nutrient sources, because of their known and uniform composition

and the predictability of their chemical reactions, but they are also more easily lost




from farm fields. Chemical and biological processes and their effects on plant

nutrients cannot be clearly separated, because inorganic nutrients are quickly

incorporated into biological cycles and biological processes release nutrients from

organic matter in plant-available, inorganic forms.

Use chemical fertilizers only after accounting for all organic nutrient

sources to avoid overloading the system and losing soluble nutrients . For many

farming systems,inorganic fertilizer will still be the largest nutrient input, but even

then it is useful to think of chemical fertilizers as supplementary nutrients. When

used to supplement biological nutrient sources, inorganic fertilizers can help make

more efficient use of other available plant-growth resources, such as water and

sunlight, by eliminating nutrient supply as the limiting factor in crop growth and

yield. Chemical processes should be managed so they work together with biological processes for a productive agriculture and healthy environment (Peter

M. Bierman, 2011).

I. Recycling Pathways

Since we are concerned more and more with recycling prob1ems, both in

nature and in commerce, it is instructive to review the subject of biogeochemistry

in terms of recycling pathways. As already indicated, recycling of many vital

nutrients involves microorganisms and energy derived from the decomposition of

organic matter.

Where small plants such as grass or phytoplankton are heavily grazed,

recycling by way of animal excretion may be important. In nutrient-poor

situations, a direct return is accomplished by symbiotic microorganisms that

become a part of autotrophs (plants), such as the mycorrhizal fungi mentioned in

the preceding section. Many substances arc recycled by physical means involving

solar energy. Finally, fuel energy is used by humans to recycle water, fertilizers,

metals, and paper. Note again that recycling requires energy dissipation from

some source, such as organic matter, solar energy , or fuel (Odum, 1989).




J. The Sediment Cycle

We learned earlier that sediment is material, in either particulate or dissolved

form, that is produced by weathering of rocks on the continents and then

transported, by some agent (water is by far the most important, in general, but

wind and moving glacier ice are important as well, at certain times and places) to

come to rest as a sediment deposit. A whole field of Earth science, sedimentary

geology, is devoted to the study of sediments, as well as the sedimentary rocks

thatare formed when sediment is buried and becomes lithified.

In a sense, the sediment cycle is simpler than the water cycle, because after

sediment is formed it inevitably moves downhill toward places of rest. From the

perspective of the Earth¶s surface, sedimentary processes are basically a matter of

source, transport, and sink. (Scientists like to use the term sink for a kind of placeto which matter moves and accumulates, or a kind of place to which energy flows

and is there stored or dissipated).

To have a full appreciation of the sediment cycle, we need to think beyond

the Earth¶s surface and the processes and kinds of environments of reservoirs

associated with it. Although sediment can be stored in lakes and in river valleys

for geologically long periods of time, and become buried deeply enough to be

converted to sedimentary rocks, most sediments end up in the world¶s oceans. The

oceans don¶t fill up, though: plate tectonics operates, in ways that are beyond the

scope of this course, to recycle the sediments and sedimentary rocks back to the

continents, there to be exposed once again to weathering and transport, to

complete the cycle.

K . References

Anonym1.2011. Sulfur Cycl e (online)(http://en.wikipedia.org/wiki/Sulfur_cycle,

acessed on 22 January 2012)

Anonym2. 2012. Carbon Cycl e,(online).(http://en.wikipedia.org/wiki/Carbon_

cycle, acessed on 22 January 2012.

Anonym3.2011. The Gl obal Carbon Cycl e, (online)(http://www.global-

greenhouse warming.com/global-carbon-cycle.html, acessed on 22

January 2012.




Bierman M. Peter, et al. 2011. N utrient Cycl ing & Maintaining S oil Fertil ity in

Fr uit and Vegetabl e Crop S ystems, (online)

(http://www.extension.umn.edu/distribution/horticulture/M1193.html,

acessed on 22 January 2012.

Butler A. Rhett. 2011. S oil s and N utrient Cycl ing in the Rain f orest , (online)

(http://rainforests.mongabay.com/0502.htm, accessed on 24 Januari 2012)

Campbell, Neil A. and Reece, Jane B. 2009. Biol ogy 8th Edition. San Fransisco :

Pearson Education.

Odum, E.P., 1989. Ecol ogy and Our Endangered Li f e-Su pport S ystem. USA:

Sinauer Associates, Inc. Publisher.

Odum, E.P.,1996. Dasar-dasar Ekol ogi (terjemahan Samingan, T.). Jogja: Gajah

Mada University PressSolomon, Eldra P., Berg, Linda R., and Martin, Diana W. 2008. Biol ogy, Eighth

Edition. USA: Thomson Brooks/Cole

Southwick, C.H. 1985. Gl obal Ecol ogy. Colorado: Sinauer Associates, Inc.

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Appl ications, Eighth Edition. USA: Brooks/Cole, Cengage Learning




STATEMENT ABOUT MATERIAL CYCLE

AND PHYSICAL CONDITION OF EXISTENCE

1. Ekosistem merupakan kumpulan komunitas yang melakukan interaksi dengan

factor abiotik.

Faktor abiotic meliputi: air, udara, cahaya, angina, batu, suhu, dll

2. Denitrifikasi merupakan proses pembentukan nitrogen oleh mikroorganisme

(bakteri, misalnya) pengurai dari sisa-sisa organisme yang telah mati.

Contoh bakteri denitrifikasi antara lain : N itrosomonas, N itrosococcu s,dan

N itrosobacter.

3. Biosfer merupakan keselurhan bioma yang ada dibumi

Contoh bioma yang ada di bumi: bioma hutan hujan tropis, bioma gurun, bioma tundra, bioma hutan jarum, savanna, dll.

4. Air tanah merupakan air yang terdapat dalam lapisan tanah atau bebatuan

dibawah permukaan tanah, contoh: sungai bawah tanah, sumur bor (artesis).

Air tanah merupakan salah satu sumber daya air yang keberadaannya terbatas

dan kerusakannya dapat mengakibatkan dampak yang luas serta

pemulihannya sulit dilakukan.

5. Akuifer merupakan suatu lapisan bebatuan (batu kapur atau batu pasir) yang

mernyerap air dari sebuah aliran air. Lapisan ini terletah diantara bebatuan

yang kedap air.

6. Ozon adalah salah satu gas yang membentuk atmosfer.

Ozon terdiri tiga molekul oksigen .Ozon adalah gas beracun sehingga bila

berada dekat permukaan tanah akan berbahaya bila terhisap dan dapat

merusak paru-paru. Sebaliknya, lapisan ozon di atmosfer melindungi

kehidupan di Bumi karena melindungi dari radiasi sinar ultraviolet yang dapat

menyebabkan kanker.

7. Greenhouse (rumah kaca) adalah sebuah bangunan di mana tanaman

dibudidayakan.

Rumah kaca sering kali digunakan untuk mengembangkan bunga, buah dan

tanaman. Rumah kaca melindungi tanaman dari panas dan dingin yang

berlebihan, melindungi tanaman dari debu dan mencegah hama.




8. Terrestrial adalah sesuatu yang berhubungan dengan daratan atau planet

bumi.

Daratan adalah bagian permukaan bumi yang tidak tertutupi oleh air laut.

Daratan merupakan tempat hidup bagi kebanyakan tumbuhan dan bagi

banyak hewan.

9. Belerang atau sulfur adalah unsur kimia yang memiliki lambang S dan nomor

atom 16.

Sulfur mempunyai banyak kegunaan industri. Belerang sangat penting untuk

kehidupan. Belerang adalah penyusun lemak, cairan tubuh dan mineral

tulang, dalam kadar yang sedikit. Di alam, belerang dapat ditemukan sebagai

unsur murni atau sebagai mineral- mineral sulfide dan sulfate

10. Samudra adalah laut yang sangat luas yang dibatasi oleh benua ataupunkepulauan yang besar. Samudra meliputi 71% permukaan bumi. Ada 4

samudra yaitu Samudra Antarktika / Lautan Selatan, Samudra Arktik,

Samudra Atlantik dan Samudra Hindia

11. Daur ulang: proses untuk menjadikan suatu bahan menjadi bahan baru dengan

tujuan menjadikan sesuatu lebih berguna.

12. Daur: suatu proses yang kembali ke keadaan awal dan mengulangnya dengan

urutan yang sama.

13. Esensial: sesuatu yang penting dibutuhkan dan dituntut untuk terpenuhi.

14. Nutrisi: substansi organik yang dibutuhkan organisme untuk fungsi normal

dalam tubuhnya.

15. Sedimen: bahan alami yang dipecah oleh proses pelapukan dan erosi yang

kemudian diangkat oleh angina, air/es, maupun gaya gravitasi yang bekerja

pada partikel itu sendiri

Documents

Matarial Cycles and Physical Condition