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  2. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    Exchanges of materials between rocks, soils, and the oceans are generally slower by comparison. [2] The flow of energy in an ecosystem is an open system; the Sun constantly gives the planet energy in the form of light while it is eventually used and lost in the form of heat throughout the trophic levels of a food web.

  3. Lichens and nitrogen cycling - Wikipedia

    en.wikipedia.org/wiki/Lichens_and_nitrogen_cycling

    Earth's mantle contains non-atmospheric nitrogen in the form of rocks and in the soil. [15] Weathering of the rocks and stone are normally caused by physical, chemical and biological processes. Plants cannot absorb nitrogen from rocks, but fungi can. Fungi within lichens can extract nutrients from mineral surfaces by secreting organic acids.

  4. Nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_cycle

    The nitrogen cycle is an important process in the ocean as well. While the overall cycle is similar, there are different players [42] and modes of transfer for nitrogen in the ocean. Nitrogen enters the water through the precipitation, runoff, or as N 2 from the atmosphere. Nitrogen cannot be utilized by phytoplankton as N

  5. Carbon-based life - Wikipedia

    en.wikipedia.org/wiki/Carbon-based_life

    Carbon is a primary component of all known life on Earth, and represents approximately 45–50% of all dry biomass. [1] Carbon compounds occur naturally in great abundance on Earth. Complex biological molecules consist of carbon atoms bonded with other elements , especially oxygen and hydrogen and frequently also nitrogen , phosphorus , and ...

  6. Coal - Wikipedia

    en.wikipedia.org/wiki/Coal

    Of particular interest is the sulfur content of coal, which can vary from less than 1% to as much as 4%. Most of the sulfur and most of the nitrogen is incorporated into the organic fraction in the form of organosulfur compounds and organonitrogen compounds. This sulfur and nitrogen are strongly bound within the

  7. Lithotroph - Wikipedia

    en.wikipedia.org/wiki/Lithotroph

    This group of bacteria are nitrogen-fixing photolithotrophs that are capable of using energy from sunlight and inorganic nutrients from rocks as reductants. [27] This capability allows for their growth and development on native, oligotrophic rocks and aids in the subsequent deposition of their organic matter (nutrients) for other organisms to ...

  8. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    A pressure-sensitive nitrogen capsule known commonly as a "widget" allows nitrogen-charged beers to be packaged in cans and bottles. [91] [92] Nitrogen tanks are also replacing carbon dioxide as the main power source for paintball guns. Nitrogen must be kept at a higher pressure than CO 2, making N 2 tanks heavier and more expensive. [93]

  9. Geochemistry of carbon - Wikipedia

    en.wikipedia.org/wiki/Geochemistry_of_carbon

    It is also found as fossil fuels in coal and petroleum and gas. Native forms of carbon are much rarer, requiring pressure to form. Pure carbon exists as graphite or diamond. [1] The deeper parts of Earth such as the mantle are very hard to discover. Few samples are known, in the form of uplifted rocks, or xenoliths.