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  2. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    The fast cycle operates through the biosphere, including exchanges between land, atmosphere, and oceans. The yellow numbers are natural fluxes of carbon in billions of tons (gigatons) per year. Red are human contributions and white are stored carbon. [30] The slow cycle operates through rocks, including volcanic and tectonic activity

  3. Marine biogeochemical cycles - Wikipedia

    en.wikipedia.org/wiki/Marine_biogeochemical_cycles

    Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle. [ 40 ] [ 41 ] [ 42 ] Human modification of the global nitrogen cycle can negatively affect the natural environment system and also human health.

  4. Flux (metabolism) - Wikipedia

    en.wikipedia.org/wiki/Flux_(metabolism)

    The activity of the enzyme catalysing the reaction; The properties of the enzyme; The metabolite concentration affecting enzyme activity. [5] Considering the above, the metabolic fluxes can be described as the ultimate representation of the cellular phenotype when expressed under certain conditions.

  5. Trace gas - Wikipedia

    en.wikipedia.org/wiki/Trace_gas

    In contrast, anthropogenic sources are caused by human activity. Some sources of a trace gas are biogenic processes, outgassing from solid Earth, ocean emissions, industrial emissions, and in situ formation. [1] A few examples of biogenic sources include photosynthesis, animal excrements, termites, rice paddies, and wetlands. Volcanoes are the ...

  6. Atmospheric carbon cycle - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_carbon_cycle

    Although individual CO 2 molecules have a short residence time in the atmosphere, it takes an extremely long time for carbon dioxide levels to sink after sudden rises, due to e.g. volcanic eruptions or human activity [17] and among the many long-lasting greenhouse gases, it is the most important because it makes up the largest fraction of the ...

  7. Oxygen cycle - Wikipedia

    en.wikipedia.org/wiki/Oxygen_cycle

    Main reservoirs and fluxes — in the biosphere (green), marine biosphere (blue), lithosphere (brown), and atmosphere (grey). The major fluxes between these reservoirs are shown in colored arrows, where the green arrows are related to the terrestrial biosphere, blue arrows are related to the marine biosphere, black arrows are related to the lithosphere, and the purple arrow is related to space ...

  8. Human impact on marine life - Wikipedia

    en.wikipedia.org/wiki/Human_impact_on_marine_life

    Human activities affect marine life and marine habitats through overfishing, habitat loss, the introduction of invasive species, ocean pollution, ocean acidification and ocean warming. These impact marine ecosystems and food webs and may result in consequences as yet unrecognised for the biodiversity and continuation of marine life forms.

  9. Sulfur cycle - Wikipedia

    en.wikipedia.org/wiki/Sulfur_cycle

    The important sulfur cycle is a biogeochemical cycle in which the sulfur moves between rocks, waterways and living systems. It is important in geology as it affects many minerals and in life because sulfur is an essential element (), being a constituent of many proteins and cofactors, and sulfur compounds can be used as oxidants or reductants in microbial respiration. [1]