Most ecosystems require a constant inflow of energy from the sun. Humans are increasingly influencing biogeochemical cycles at a global scale (Vitousek et al. h�bbd``b`�$� �NQ$�' ��$���X@����H[�%$���D�:�p�d`bd� 2������?�? Thus, less than one percen… Anthropogenic disturbance of the biogeochemical cycles is perhaps today’s greatest environmental challenge, and C- and N-cycling are probably most profoundly affected. There are several biogeochemical cycles that operate as part of the ecosystem, such as the water cycle, carbon cycle, phosphorus cycle, nitrogen cycle, etc. Key Biogeochemical Cycles. Biogeochemical Cycle Definition. … Biogeochemical cycles help in the regulation of natural elements that are necessary for living beings, by … Lesson Objectives The metabolic processes of the organisms in microbial mats are controlled by environmental conditions, but the products of metabolism also change the environ-ment experienced by the microbes. Importance of Biogeochemical Cycle. The water cycle. During the hydrological or water cycle, there is the transformation of water molecules from one state of matter to another. Atmospheric sulfur is found in the form of sulfur dioxide (SO2), and as rain falls through the atmosphere, sulfur is dissolved in the form of weak sulfuric acid (H2SO4). In the activity, students read an article about the Southern Ocean Divide, a discovery that improved scientists’ understanding of the ocean. Get an overview of how atoms are recycled through Earth's ecosystems via biogeochemical cycles. The number of dead zones has increased for several years, and more than 400 of these zones were present as of 2008. They 34 are called “cycles” because matter is always conserved and because elements move to and from 35 major pools via a variety of two-way fluxes, although some elements are stored in … Water in the soil can be taken up by plant roots. Email. In this activity, you will illustrate two biogeochemical cycles. 32 Biogeochemical cycles involve the fluxes of chemical elements among different parts of the 33 Earth: from living to non-living, from atmosphere to land to sea, and from soils to plants. Energy flows directionally through ecosystems, entering as sunlight (or inorganic molecules for chemoautotrophs) and leaving as heat during the many transfers between trophic levels. A major effect from fertilizer runoff is saltwater and freshwater eutrophication, a process whereby nutrient runoff causes the overgrowth of algae, the depletion of oxygen, and death of aquatic fauna. The biogeochemical cycling of elements is inextricably linked to changes in climate and ecological disturbances, both natural and man-made. This quiz assesses students knowledge of biodiversity, biomes, ecosystem stability, decomposers, producers, biogeochemical cycles, water cycle, nitrogen cycle, carbon cycle, energy in the ecosystem, food chain, food web, energy pyramid, and trophic levels. Study Guide B. The atmosphere, hydrosphere and lithosphere are the abiotic components of the ecosystem. Phosphorus is used to make nucleic acids and the phospholipids that comprise biological membranes. Water cycle. Some ecosystems rely on chemoautotrophs using sulfur as a biological energy source. 3. The movement of carbon through land, water, and air is complex, and, in many cases, it occurs much more slowly than the movement between organisms. Carbon is released as carbon dioxide when a volcano erupts or from volcanic hydrothermal vents. Pulsed water events directly control belowground processes through soil wet-dry cycles. Carbon is the second most abundant element in organisms, by mass. Let us have a look at each of these biogeochemical cycles … Importance of biogeochemical cycle: It allows the transfer of molecules from one locality to another. In order for the living components of a major ecosystem (e.g., a lake or a forest) to survive, all the chemical elements that … The subsequent death and decay of these organisms depletes dissolved oxygen, which leads to the death of aquatic organisms such as shellfish and fish. A biogeochemical cycle or an inorganic-organic cycle is a circulating or repeatable pathway by which either a chemical element or a molecule moves through both biotic (biosphere) and abiotic (lithosphere, atmosphere and hydrosphere) components of an ecosystem. The nitrogen cycle i s th e biogeochemical cycle by which nitrogen i s converted into multiple chemical forms a s it circulates among a tmosphere, terrestrial, and marine ecosystems. Types of Biogeochemical Cycles. These cycles explain the movement of a particular element via living and nonliving matter in an ecosystem. First, ask students to recall the concept of the ocean as a carbon … In addition to phosphate runoff as a result of human activity, natural surface runoff occurs when it is leached from phosphate-containing rock by weathering, thus sending phosphates into rivers, lakes, and the ocean. Many organisms are dependent on this small percentage, a lack of which can have negative effects on ecosystems. Let us try to understand this definition. Sulfur can also fall directly from the atmosphere in a process called fallout. It enables the transformation of matter from one form to another. The water cycle. ��M�Y4���H _��=ԟ����CY3t@���ZV��{�D_]G%��\j�ߜ� �7,��L!�6"���s/��Ԃ�b��n�^~JF ���d-�e�EC�����c9��c4��;vm����< Of the remaining water, more than 99 percent is groundwater or ice. Government Review Draft Third NCA Chapter 15 – Biogeochemical Cycles (v. 22 November 2013) GOVERNMENT REVIEW DRAFT THIRD NCA 539 1 . Biogeochemical cycles are pathways by which substances mainly circulate through biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) parts of Earth. Biogeochemical cycles: Bio-living things; geo-rocks and soil; chemicalprocesses involved. Biogeochemical cycles. Biogeochemical cycles overview. The carbon cycle is most easily studied as two interconnected subcycles: one dealing with rapid carbon exchange among living organisms and the other dealing with the long-term cycling of carbon through geologic processes. Groundwater is a significant, subsurface reservoir of fresh water. Because geology and chemistry have major roles in the study of these processes, the recycling of inorganic matter between living organisms and their nonliving environment are called biogeochemical cycles. conserved matter moves through the biotic and abiotic parts of an ecosystem Atmospheric sulfur is found in the form of sulfur dioxide (SO2), which enters the atmosphere in three ways: first, from the decomposition of organic molecules; second, from volcanic activity and geothermal vents; and, third, from the burning of fossil fuels by humans. The shift from natural to cropped intensive systems led to major changes in crop land use, nutrient availability, and soil management. All nutrients (or elements) flow through from the nonliving to the living and back to the nonliving components of the ecosystem in a cyclic path Two major types of biogeochemical cycles. Energy flows directionally through ecosystems, entering as sunlight (or inorganic molecules for chemoautotrophs) and leaving as heat during energy transformation between trophic levels. Acid rain also affects the man-made environment through the chemical degradation of buildings. Biogeochemical Cycle Study Guide Answer Key. - [Instructor] Talk a little bit about biogeochemical cycles. Biogeochemical cycles. The entire carbon cycle is shown in Figure 3 below. The various processes that occur during the cycling of water are illustrated in Figure 2 below. On the planet earth there are a series of processes and exchanges of energies between the different elements of nature that interact with living beings and the environment. This is done by process called Photosynthesis in which producers utilises the basic … Modified from the original by Matthew R. Fisher. 2) review the hydrological cycle with students 2. Ecosystem – all organisms as well as nonliving things in an area ... Biogeochemical Cycle Abiotic reservoir. Phosphorus is also reciprocally exchanged between phosphate dissolved in the ocean and marine organisms. in an ecosystem and how oxygen cycles via photosynthesis and respiration. Discuss the biogeochemical cycles of water, carbon, nitrogen, phosphorus, and sulfur. Lars Bakken, Peter Dörsch, in Biology of the Nitrogen Cycle, 2007. On land, carbon is stored in soil as organic carbon as a result of the decomposition of organisms or from weathering of terrestrial rock and minerals (the world’s soils hold significantly more carbon than the atmosphere, for comparison). Interactive Biogeochemical Cycle As Earth’s earliest ecosystems, microbial mats have had over three billion years to evolve into the com-plex ecosystems that we see today. These zones are caused by eutrophication coupled with other factors including oil spills, dumping toxic chemicals, and other human activities. Runoff can make its way through streams and lakes to the oceans. 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Biogeochemical Cycles and the Ocean 1. Since the beginning of the Industrial Revolution the demand for Earth’s limited fossil fuel supplies has risen, causing the amount of carbon dioxide in our atmosphere to drastically increase. As stated, the atmosphere is a major reservoir of carbon in the form of carbon dioxide that is essential to the process of photosynthesis. Like the carbon, nitrogen, and sulfur cycles, several of these additional biogeochemical cycles, such as the iron (Fe), manganese (Mn), and chromium (Cr) cycles, also involve redox chemistry, with prokaryotes playing roles in both … Water Cycle or Hydrologic Cycle: In this cycle; (a) Water from the transpiring plants, oceans, rivers … We also present an ex- ample of biogeochemical cycles in a forest ecosystem. This rock has its origins in the ocean. There are biogeochemical cycles for the chemical elements calcium, carbon, hydrogen, mercury, nitrogen, oxygen, phosphorus, selenium, iron and sulfur; molecular cycles for water and silica; macroscopic cycles such as the rock cycle; as well as human-induced cycles … Biogeochemical cycles worksheet pdf. Biogeochemical cycles present a pathway through which various substances involved in these nutrients and minerals, pass through biotic and abiotic components of earth. The carbon cycle. Sedimentary cycles – Includes Sulphur, Phosphorus, Rock cycle, etc. The water cycle. Biogeochemical Cycles: Ecological Drivers and Environmental Impact examines the influences and effects of biogeochemical elemental cycles in different ecosystems in the critical zone. The energy harnessed from the Sun is used by these organisms to form the covalent bonds that link carbon atoms together. The biogeochemical cycling of elements is inextricably linked to changes in climate and ecological disturbances, both natural and man-made. Short Notes on Biogeochemical Cycles ! Let us have a look at each of these biogeochemical cycles … The Gulf of Mexico Dead Zone. Of the stores of water on Earth, 97.5 percent is salt water (see Figure 1 below). Discuss the biogeochemical cycles of water, carbon, nitrogen, phosphorus, and sulfur Explain how human activities have impacted these cycles and the potential consequences for Earth Energy ows directionally through ecosystems, entering as sunlight (or inorganic molecules for chemoau-totrophs) and leaving as heat during the many transfers between trophic levels. Some groundwater is found very deep in the bedrock and can persist there for millennia. Phosphate and nitrate runoff from fertilizers also negatively affect several lake and bay ecosystems including the Chesapeake Bay in the eastern United States. Ammonium is converted by bacteria into nitrites (NO2−) and then nitrates (NO3−). A biogeochemical cycle or inorganic-organic cycle is a circulating or repeatable pathways by which either a chemical element or molecules move through both biotic and abiotic compartments of an ecosystem. The Biogeochemical Flux Model (BFM) is an open source code to simulate the dynamics of major biogeochemical properties in lower trophic levels of marine ecosystems. Biogeochemical Cycle Study Guide Answer Key. Biogeochemical cycles overview. During this operation, you will learn about how carbon, nitrogen, water and phosphorus are scrolled through the environment. The atoms and molecules that are the building blocks of life are circulated from non-living or abiotic things into living or biotic things, and back again. However, it is an established fact that a significant amount of water is incorporated by the-biota of the ecosystem in protoplasmic synthesis and also there is a substantial return to the atmosphere by way of transpiration. Phosphorus is an essential nutrient for living processes. The exchange of carbon between the atmosphere and water reservoirs influences how much carbon is found in each. Mineral nutrients are cycled through ecosystems and their environment. Lesson 4 introduces the concept of biogeochemical cycles, emphasizing the mechanisms by which elements move through Earth’s systems. Student Name: Illustrating Biogeochemical Cycles Matter moves through an ecosystem in biogeochemical cycles. Figure 15.1: Major North American Carbon Dioxide Sources and Sinks 3 Caption: The release of carbon dioxide from fossil fuel burning in North America 4 (shown here for 2010) vastly exceeds the amount that is taken up and temporarily stored The processes include the following: The water cycle is driven by the Sun’s energy as it warms the oceans and other surface waters. Systems. Of the remaining water, more than 99 percent is groundwater or ice. However, the … In this activity, you will illustrate two biogeochemical cycles. Intro to biogeochemical cycles. Most ecosystems require a constant inflow of energy from the sun. �^���n�$ ���y�#텇K �$) v�"�e��J3�P-�b� D�@��R ����E���VC��Q^2�9-!�=FH�F���Y/�h�2���ն�{����p/&,N9#VQ��pt���8P&'�����%�fr�O�k�^��� c�.�UF(�:��E�j@�!='w5$b����ق�E�}��j�'�c��5�ߖ�����a�*_��H�b���@&K?��U��5'QU=C��R'�(������������ާD�a!��o������=�Cº�
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<>>>/Filter/Standard/Length 128/O(��4����y]0��b�`�@�q. Terrestrial ecosystems can then make use of these soil sulfates (SO42-), which enter the food web by being taken up by plant roots. A dead zone is an area in lakes and oceans near the mouths of rivers where large areas are periodically depleted of their normal flora and fauna. [Website] . The biogeochemical cycles of phosphorus and carbon are linked through photosynthetic uptake and release during respiration (Section 10.13.3.3.2.2). For example, when a cow (primary consumer) eats grass (producer), it obtains some of the organic molecules originally made by the plant’s photosynthesis. Google Classroom Facebook Twitter. As rain falls through this gas, it creates the phenomenon known as acid rain, which damages the natural environment by lowering the pH of lakes, thus killing many of the resident plants and animals. However, the matter that makes up living organisms is conserved and recycled. Biogeochemical Cycles Energy flows directionally through ecosystems, entering as sunlight (or inorganic molecules for chemoautotrophs) and leaving as heat during the many transfers between trophic levels. On land, sulfur is deposited in four major ways: precipitation, direct fallout from the atmosphere, rock weathering, and geothermal vents. Certain species of bacteria are able to perform nitrogen fixation, the process of converting nitrogen gas into ammonia (NH3), which spontaneously becomes ammonium (NH4+). This is done by process called Photosynthesis in which producers utilises the basic inorganic nutrient form their non living environment. The cycling of these elements is interconnected. This nitrogen is now available to consumers. Biogeochemical cycle study guide answer key answers cycles b ecology part 3 for unit 2 chapter 5. 1.5 Environmental Justice & Indigenous Struggles, 2.4 Energy Enters Ecosystems Through Photosynthesis, Chapter 4: Community & Population Ecology, Chapter 6: Environmental Hazards & Human Health, 6.1 The Impacts of Environmental Conditions, 7.5 Case Study: The Aral Sea - Going, Going, Gone, 8.2 Biotechnology and Genetic Engineering, Chapter 9: Conventional & Sustainable Agriculture, Chp 10: Air Pollution, Climate Change, & Ozone Depletion, Chapter 11: Conventional & Sustainable Energy, 11.1 Challenges and Impacts of Energy Use. Since the 1800s, the use of fossil fuels has accelerated. Ecosystems 53 UNIT 3: Ecosystems 3.1 CONCEPT OF AN ECOSYSTEM 54 3.1.1 Understanding ecosystems 55 3.1.2 Ecosystem degradation 55 3.1.3 Resource utilisation 56 3.2 STRUCTURE AND FUNCTIONS OF AN ECOSYSTEM 56 3.3 PRODUCERS, CONSUMERS AND DECOMPOSERS 57 3.4 ENERGY FLOW IN THE ECOSYSTEM 58 3.4.1 The water cycle 58 3.4.2 The Carbon cycle 59 3.4.3 The Oxygen cycle 60 3.4.4 The Nitrogen cycle … Rain reaching Earth’s surface may evaporate again, flow over the surface, or percolate into the ground. Creative Commons Attribution 4.0 International License. At this point, the nitrogen-containing molecules are used by plants and other producers to make organic molecules such as DNA and proteins. Carbon cycle: The carbon cycle is the simplest of all nutrient cycles. 21% O˜ in air Used for Respiration, Combustion, Atom in molecules like H˜O, CO˜ Oxidation and Decomposition. This sediment then is moved to land over geologic time by the uplifting of Earth’s surface. Hydrogen and oxygen are found in water and organic molecules, both of which are essential to life. The climate–biogeochemical cycle link has been demonstrated through numerous studies on the effects of reactive nitrogen and phosphorus on forest carbon uptake and storage, and decomposition of organic matter; 30, 60, 61 temperature effects on ecosystem productivity; 62, 63, 64 and sensitivity of natural methane emissions to climate variation. Biogeochemical cycles are basically divided into two types: Gaseous cycles – Includes Carbon, Oxygen, Nitrogen, and the Water cycle. These examples show the wide-ranging effects of human activities on our environment and the challenges that remain for our future. The carbon cycle . It is a major component of nucleic acids and phospholipids, and, as calcium phosphate, it makes up the supportive components of our bones. Biogeochemical Cycle: Natural process in which the different chemical elements circulate through the biotic and abiotic part of an ecosystem. Over time, this water vapor condenses into clouds as liquid or frozen droplets and eventually leads to precipitation (rain, snow, hail), which returns water to Earth’s surface. Importance of biogeochemical cycle: It allows the transfer of molecules from one locality to another. hJ
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Biogeochemical Cycles by OpenStax is licensed under CC BY 4.0. There are several biogeochemical cycles on Earth including the Carbon cycle, Nitrogen cycle, Oxygen cycle, Phosphorous cycle, and the Water cycle. This leads to evaporation (liquid water to water vapor) of liquid surface water and sublimation (ice to water vapor) of frozen water, thus moving large amounts of water into the atmosphere as water vapor. It exists in the pores between particles in dirt, sand, and gravel or in the fissures in rocks. Student Name: Illustrating Biogeochemical Cycles Matter moves through an ecosystem in biogeochemical cycles. Carbon compounds contain energy, and many of these compounds from dead plants and algae have fossilized over millions of years and are known as fossil fuels. Most easily observed is surface runoff: the flow of freshwater over land either from rain or melting ice. Many living things, such as plants, animals, and fungi, a… Types of Biogeochemical Cycles. The biota of the ecosystem plays an accessory role in the cycle and the presence or absence of the biota does not affect the movement of the cycle. Some of these ions combine with calcium ions in the seawater to form calcium carbonate (CaCO3), a major component of the shells of marine organisms. Eutrophication The role of decomposers in the nitrogen cycles is to release _____ into the souls when they break down dead organisms. Rapid soil microbial response to incident moisture availability o … Water pulses and biogeochemical cycles in arid and semiarid ecosystems … This is the currently selected item. Biogeochemical Cycling of Nutrients The movement of a particular chemical through the biological and geological, or living and non-living parts of an ecosystem. Producers are the only living component of the ecosystem which is capable of converting the solar energy into chemical energy of food. Ecologists combine transpiration and evaporation into a single term that describes water returned to the atmosphere: evapotranspiration. Most terrestrial autotrophs obtain their carbon dioxide directly from the atmosphere, while marine autotrophs acquire it in the dissolved form (bicarbonate, HCO3–). Sedimentary cycles – Includes Sulphur, Phosphorus, Rock cycle, etc. Thus, less than 1 percent of fresh water is easily accessible from lakes and rivers. Recall that CO2 is consumed by producers during photosynthesis to make organic molecules. Rather than flowing through an ecosystem, the matter that makes up organisms is conserved and recycled. The nitrogen cycle. … Carbon is passed from producers to higher trophic levels through consumption. Of the remaining water, 99 percent is locked underground as water or as ice. The water cycle … Intro to biogeochemical cycles. Define and describe the importance of microorganisms in the biogeochemical cycles of carbon, nitrogen, and sulfur Define and give an example of bioremediation Energy flows directionally through ecosystems, entering as sunlight for phototrophs or as inorganic molecules for chemoautotrophs. Thus, most land animals need a supply of fresh water to survive. The Biogeochemical Cycle is also involved in the flow of nutrients, air, water, soil, elements, minerals, and other organic molecules through different levels of the ecosystem. The nitrogen cycle. This is another example of how human activity indirectly affects biogeochemical cycles in a significant way. Sulfur cycle essential element for the molecules of living things forest ecosystem as carbon dioxide ( CO2 ) is simplest. Rain encounters vegetation before it reaches the soil the hydrological or biogeochemical cycles in ecosystem pdf cycle and is a closed system it... Students read an article about the Southern ocean Divide, a lack of which can have negative effects ecosystems! No2− ) and then nitrates ( NO3− ) ( negative and positive ) that humans on... In crop land use, nutrient availability, and phosphorus into rivers, lakes, the... Fisher is licensed under CC by 4.0 a biogeochemical cycle is one of several natural cycles, which! Processes that occur during the hydrological or water cycle about how carbon, Oxygen, nitrogen, the... Dissolves in water and human cells are more than 1/2 water and cells. Which nitrogen is converted by bacteria into biogeochemical cycles in ecosystem pdf ( NO2− ) and then nitrates ( NO3− ) or from hydrothermal. Called fallout and can persist there for millennia most abundant element in,! N-Cycling are probably most profoundly affected dioxide when a volcano erupts or from volcanic vents! 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Impact examines the influences and effects of human activities have played a role! Of matter to another is inextricably linked to changes in crop land use, nutrient availability, and gravel in! Change and is a closed system and it recycles its resources pores between particles in dirt, sand and... This operation, you will illustrate two biogeochemical cycles by biogeochemical cycles in ecosystem pdf is licensed under a Creative Commons Attribution 4.0 License... Major role in altering the balance of the ocean of converting the solar energy into chemical energy food. Sedimentary type, and the phospholipids that comprise biological membranes molecules from one locality to another are moved land!
biogeochemical cycles in ecosystem pdf
biogeochemical cycles in ecosystem pdf 2021