Biogeochemical Cycles
Biogeochemical cycles are pathways through which elements such as carbon, nitrogen, and phosphorus move through the biotic and abiotic components of the Earth. These cycles involve processes like photosynthesis, respiration, decomposition, and weathering, and play a crucial role in maintaining the balance of nutrients and elements in ecosystems. They are essential for sustaining life and regulating the Earth's systems.
8 Key excerpts on "Biogeochemical Cycles"
eBook - ePub- Robert L. Tate(Author)
- 2020(Publication Date)
- Wiley-Blackwell(Publisher)
...Added complexity is introduced when the elements of concerns exists in several oxidation states (e. g., nitrogen, sulfur as well as metal ions such as iron, and aluminum. Therefore, an evaluation of Biogeochemical Cycles must include consideration of the totality of biological, chemical, and physical interactions associated with the movement of nutrients between organic and inorganic pools and the variety of geochemical reservoirs existent within an ecosystem. This definition of the complete realm of Biogeochemical Cycles emphasizes the point that study of these chemical transformations has real implications beyond the world of plant science and general biology. Study of these cycles of life‐sustaining nutrients is also essential for such broad‐based disciplines as general ecology or environmental science. For example, consideration of Biogeochemical Cycles in disturbed environments is essential for optimizing anthropogenic activities for ecosystem sustenance as well as in development of management plans for restoration or reclamation of damaged systems; that is, development of appropriate ecosystem stewardship procedures. As suggested by the foregoing analysis, a study of Biogeochemical Cycles requires a means of assessing a wide array of complex interactions within a constantly varying environment. Some details may be studied in isolation, but it must be remembered that the primary objective of the exercise is to develop an understanding of the overall pattern of distribution and movement of nutrients in the ecosystem and their impact on ecosystem function and sustainability as well as evolution. A means of developing an overarching framework for study of Biogeochemical Cycles is to assemble the data into models. These models may be used to elucidate gaps in knowledge, provide hypotheses for future study, and develop experimental plans for quantifying nutrient movement within the cycles and assessment of the impact of environmental modification on these processes...
eBook - ePubAir Pollution Calculations
Quantifying Pollutant Formation, Transport, Transformation, Fate and Risks
- Daniel A. Vallero(Author)
- 2019(Publication Date)
- Elsevier(Publisher)
...The extent and likelihood that a substance will move and where it may move and end up in the environment, that is, its fate, can be estimated by quantifying these mechanisms and matching them with the inherent properties of the substance. The physical and chemical mechanisms and properties will also determine whether the substance and its transformation products are likely to become more or less toxic and more or less mobile. The biogeochemical cycle is a means of depicting how matter and energy move through trophic states within biological organizations and how the abiotic, nonliving components of a system interact with the biotic, living components. It is a means of keeping track of the mass and energy balances, both thermodynamically and fluid dynamically [1]. This chapter specifically addresses the cycles of carbon; environmental nutrients, especially N and sulfur (S); and metals. The cycles of other substances are also important to air pollution management. Energy is discussed in this chapter as part of the Biogeochemical Cycles, for example, light in photosynthesis and heat’s role in solubility and volatilization and thermal reactions. These cycles depend on the water cycle and processes that are discussed in Chapter 7. 8.2 Spheres and cycles The lithosphere affects air pollution in many ways. The geomorphology of an area can influence and even dictate where people live; for example, most cities are in coastal plains and in valleys near waterways. The terrain also determines wind patterns and air circulation; for example, inversions in urban valleys can greatly exacerbate air pollution episodes, and land-sea breezes can improve or degrade air quality depending on the direction. An example of a physical mechanism occurs when the molecular configuration engenders its substantial expansion by volume as it freezes, that is, change of state from liquid to solid, or when it sublimates, that is, change of state from gas to solid...
eBook - ePubEcology
From Individuals to Ecosystems
- Michael Begon, Colin R. Townsend(Authors)
- 2020(Publication Date)
- Wiley(Publisher)
...Nutrient recycling is never perfect and some nutrients are exported from land by runoff into streams (ultimately to lakes and oceans) and others, such as nitrogen and sulphur, that have gaseous phases, can be lost to the atmosphere. Moreover, a community receives additional supplies of nutrients that do not depend directly on inputs from recently decomposed matter – minerals dissolved in rain, for example, or derived from weathered rock. 21.1.2 Biogeochemistry and Biogeochemical Cycles the ‘bio’ in biogeochemistry We can conceive of pools of chemical elements existing in compartments. Some compartments occur in the atmosphere (carbon in CO 2, nitrogen as gaseous nitrogen, etc.), some in the rocks of the lithosphere (calcium as a constituent of calcium carbonate, potassium in feldspar) and others in the hydrosphere – the water in soil, streams, lakes or oceans (nitrogen in dissolved nitrate, phosphorus in phosphate, carbon in carbonic acid, etc.). In all these cases the elements exist in an inorganic form. In contrast, living organisms (the biota) and dead and decaying bodies can be viewed as compartments containing elements in an organic form (carbon in cellulose or fat, nitrogen in protein, phosphorus in adenosine triphosphate, etc.). Studies of the chemical processes occurring within these compartments and, more particularly, of the fluxes of elements between them, comprise the science of biogeochemistry. Many geochemical fluxes would occur in the absence of life, if only because all geological formations above sea level are eroding and degrading. Volcanoes release sulphur into the atmosphere whether there are organisms present or not. On the other hand, organisms alter the rate of flux and the differential flux of the elements by extracting and recycling some chemicals from the underlying geochemical flow...
eBook - ePubExploring Environmental Issues
An Integrated Approach
- David D. Kemp(Author)
- 2004(Publication Date)
- Routledge(Publisher)
...Thus the plants and animals and other less visible constituents of the biosphere are secondary environmental elements dependent upon interaction with the primary components — lithosphere, atmosphere and hydrosphere — for their continued existence (Box 3.1). Without the appropriate mix of gases in the atmosphere or the water in the hydrosphere, the earth' s flora and fauna could not survive. Because it represents the results of a wide range of interactions, the biosphere is the most complex of all the spheres that make up the global environment, and perhaps as a result it often provides the first indications of environmental change. SOIL Supplying the essential link between the abiotic (non-living) and biotic (living) groups in the BOX 3.1 Biogeochemical Cycles Essential to the successful operation of a closed material flow system such as the earth/atmosphere system are procedures that allow an element to be used and reused an infinite number of times. This is accomplished through a biogeochemical cycle in which an element moves between sources and sinks along well established pathways. To facilitate progress through the cycle, it may change state - from a liquid to gas, for example - often in combination with other chemicals and involve both organic and inorganic phases. Although any given cycle is ultimately balanced, flow-through is normally uneven. Quantities of an element may be shunted out of the cycle for periods of time. Carbon and phosphorus, for example, are regularly stored in the oceans, perhaps for years at a time, before becoming active in their respective cycles again. Similarly, fossil fuel deposits represent carbon that has not been directly involved in the carbon cycle for millions of years. Several current global issues involve disruption of biogeo-chemical cycles...
eBook - ePubWaste
A Handbook for Management
- Trevor Letcher, Daniel A. Vallero(Authors)
- 2019(Publication Date)
- Academic Press(Publisher)
...Chapter 5 Waste and Biogeochemical Cycling Daniel A. Vallero Department of Civil and Environmental Engineering, Duke University, Durham, NC, United States Abstract Waste management requires an understanding of how matter and energy move and change within the environment. This chapter discusses the cycles of water, carbon, nitrogen, and other substances in terms of the biological, chemical, and physical processes and mechanisms responsible for these cycles. Keywords Biogeochemical cycle; Hydrosphere; Hydrologic cycle; Carbon cycle; Carbon equilibrium; Nitrogen cycle; Trophic state; Biological organization; Sulfur cycle Outline 1 Introduction 2 The Hydrologic Cycle 2.1 The Hydrosphere 3 Scale and Complexity of Matter and Energy Cycles 4 Carbon Equilibrium and Cycling 5 Nutrient Cycling 5.1 The Nitrogen Cycle 5.2 Interactions Between Sulfur and Nitrogen 5.3 The Sulfur Cycle 6 Biogeochemical Cycles and Decision Making References 1 Introduction The earth is a dynamic system of systems in which matter and energy cycle into and out of myriad compartments in the environment. The amount, the chemical form, and the location determine whether a chemical substance is essential or detrimental. Nitrogen (N), for example, is an indispensable nutrient for plants. However, plants can only use certain bioavailable forms in soil. Under many conditions, such as excessive concentrations, transformations by biota into toxic chemical forms, or moving into drinking water supplies, this same N can become air, water, and soil pollutants. Both matter and energy cycle through the environment, so an understanding of wastes requires consideration of the physical mechanisms by which substances and energy move and change. These mechanisms can be combined with the inherent properties of a chemical to estimate the extent to which a chemical will be more or less likely to move and where it may move in the environment...
eBook - ePubThe Global Carbon Cycle and Climate Change
Scaling Ecological Energetics from Organism to the Biosphere
- David E. Reichle(Author)
- 2019(Publication Date)
- Elsevier(Publisher)
...Chapter 10 The global carbon cycle and the biosphere Abstract Industrialization and changes in the landscape have disturbed natural geochemical cycles of carbon and other elements significantly for several centuries. Fossil fuel emissions are the main contributor, along with deforestation and cement production. Projection of future trends in atmospheric CO 2 and global carbon flows, under human disturbance, requires understanding of the natural exchanges between atmosphere, marine and terrestrial ecosystems, and geosphere pools. Regulation of the rates of flux in the global carbon cycle occur in enumerable biogeochemical processes, but overall through major feedbacks in the biogeochemical cycle of carbon through weathering, photosynthetic fixation, respiratory metabolism, and the ocean calcium carbonate buffering system...
eBook - ePub30-Second Climate
The 50 most topical events, measures and conditions, each explained in half a minute
- Joanna D Haigh(Author)
- 2019(Publication Date)
- Ivy Press(Publisher)
...LIFE & Biogeochemical Cycles LIFE & Biogeochemical Cycles GLOSSARY biomass Biomass is a measure of the total mass of all living organisms in an environment or area. It may be calculated at a population, species or global level, or for a particular trophic level in the food chain. The amount of biomass present at one trophic level determines the biomass available to creatures in the trophic level above. See trophic level. climax community The final result of succession in an undisturbed environment, a climax community is a stable ecosystem that will persist indefinitely unless disturbed. Ecological communities are thought to progress from early colonists on bare rock to a forest ecosystem, in the absence of factors such as fire, grazing or climatic changes. ecosphere The term ‘ecosphere’ refers to the interactions between all living organisms, and between living organisms and the non-living components of their environment such as air, water and rock. gross primary production (GPP) The total amount of chemical energy produced as biomass from photosynthesis. Some of this chemical energy will be used up in respiration; the remainder will be stored as organic matter, known as net primary production. GPP is influenced by the availability of solar energy. hydrosphere The sum of all the water on the planet. This includes water in rivers, streams, lakes and oceans, as well as moisture held in the atmosphere and underground. Water is carried between the different components of the hydrosphere by the hydrological cycle, driven by evaporation and precipitation. lithosphere The rigid outer layer of a planet is called the lithosphere. On Earth, the lithosphere includes the crust and a portion of the upper mantle that displays elastic properties over time scales of thousands of years. The lithosphere is divided into tectonic plates, which can move in relation to each other over geological timescales...
eBook - ePubClimate Change and the Oceanic Carbon Cycle
Variables and Consequences
- Isabel Ferrera, Isabel Ferrera(Authors)
- 2017(Publication Date)
- Apple Academic Press(Publisher)
...PART I UNDERSTANDING THE IMPORTANCE OF OCEAN BIOGEOCHEMISTRY CHAPTER 1 Grand Challenges in Marine Biogeochemistry ERIC P. ACHTERBERG Grand Challenges in Marine Biogeochemistry. © Achterberg EP. Frontiers in Marine Science 1,7 (2014). doi: 10.3389/fmars.2014.00007. Licensed under Creative Commons Attribution 3.0 Unported License, http://creativecommons.org/licenses/by/3.0/. 1.1 INTRODUCTION The ocean plays a central role in our earth’s climate system and also provides a range of important ecosystem services, including food, energy, transport, and nutrient cycling. Marine biogeochemistry focuses on the study of complex biological, chemical, and physical processes involved in the cycling of key chemical elements within the ocean, and between the ocean and the seafloor, land and atmosphere. The ocean is increasingly perturbed by human induced alterations to our planet, including anthropogenic emissions of nitrogen, phosphorus, carbon and trace elements, and climate change. The establishment of a detailed understanding of biogeochemical processes, including their rates, is essential to the identification and assessment of climatic and chemical feedbacks associated with changes in the chemical and physical environment that are mediated through ocean biology, chemistry and physics. Important research areas in marine biogeochemistry involve the cycling of organic and inorganic forms of carbon, nitrogen and phosphorus, the cycling and biological roles of essential trace elements, and the fate and climatic impact of marine produced trace gases. 1.2 GREENHOUSE GASES The concentrations of atmospheric greenhouse gases (GHGs; primarily CO 2, CH 4 and N 2 O) are currently ca. 40% higher for CO 2, 150% for CH 4 and 19% for N 2 O compared with pre-industrial levels (Myhre et al., 2013), and surpass levels seen over the past 650,000 years or more. Furthermore, there is no paleo analogue available for the present rate of increase in the atmospheric GHG concentrations...
