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("Cycling Of Substances" OR "Kretslopp") 2600+ documents
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What does (cycling Of Substances Or Kretslopp) mean? Let's check what the community at Wikipedia thinks
På svenska: Kretslopp kan syfta på: Biogeokemiskt kretslopp – inom ekologi och geovetenskap den cirkulation som varje grundämne, förening eller molekyl företar, då den färdas genom de biotiska och abiotiska delarna av ett ekosystem Kolcykeln – ett biogeokemiskt kretslopp Kvävets kretslopp – en cykel som innefattar kväve och ämnen som innehåller kväve Syrets kretslopp – ett kretslopp som grundämnet syre ingår i Vattnets kretslopp – den hydrologiska cykeln Lär dig mer på Wikipedia
In English: A biogeochemical cycle, or more generally a cycle of matter, is the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth's crust. Major biogeochemical cycles include the carbon cycle, the nitrogen cycle and the water cycle. In each cycle, the chemical element or molecule is transformed and cycled by living organisms and through various geological forms and reservoirs, including the atmosphere, the soil and the oceans. It can be thought of as the pathway by which a chemical substance cycles (is turned over or moves through) the biotic compartment and the abiotic compartments of Earth. The biotic compartment is the biosphere and the abiotic compartments are the atmosphere, lithosphere and hydrosphere. For example, in the carbon cycle, atmospheric carbon dioxide is absorbed by plants through photosynthesis, which converts it into organic compounds that are used by organisms for energy and growth. Carbon is then released back into the atmosphere through respiration and decomposition. Additionally, carbon is stored in fossil fuels and is released into the atmosphere through human activities such as burning fossil fuels. In the nitrogen cycle, atmospheric nitrogen gas is converted by plants into usable forms such as ammonia and nitrates through the process of nitrogen fixation. These compounds can be used by other organisms, and nitrogen is returned to the atmosphere through denitrification and other processes. In the water cycle, the universal solvent water evaporates from land and oceans to form clouds in the atmosphere, and then precipitates back to different parts of the planet. Precipitation can seep into the ground and become part of groundwater systems used by plants and other organisms, or can runoff the surface to form lakes and rivers. Subterranean water can then seep into the ocean along with river discharges, rich with dissolved and particulate organic matter and other nutrients. There are biogeochemical cycles for many other elements, such as for oxygen, hydrogen, phosphorus, calcium, iron, sulfur, mercury and selenium. There are also cycles for molecules, such as water and silica. In addition there are macroscopic cycles such as the rock cycle, and human-induced cycles for synthetic compounds such as for polychlorinated biphenyls (PCBs). In some cycles there are geological reservoirs where substances can remain or be sequestered for long periods of time. Biogeochemical cycles involve the interaction of biological, geological, and chemical processes. Biological processes include the influence of microorganisms, which are critical drivers of biogeochemical cycling. Microorganisms have the ability to carry out wide ranges of metabolic processes essential for the cycling of nutrients and chemicals throughout global ecosystems. Without microorganisms many of these processes would not occur, with significant impact on the functioning of land and ocean ecosystems and the planet's biogeochemical cycles as a whole. Changes to cycles can impact human health. The cycles are interconnected and play important roles regulating climate, supporting the growth of plants, phytoplankton and other organisms, and maintaining the health of ecosystems generally. Human activities such as burning fossil fuels and using large amounts of fertilizer can disrupt cycles, contributing to climate change, pollution, and other environmental problems. Learn more at Wikipedia
