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  2. Nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_cycle

    The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple ... found in a wide variety of bacteria ... and leached out of rocks. Iron ...

  3. 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.

  4. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    The six aforementioned elements are used by organisms in a variety of ways. Hydrogen and oxygen are found in water and organic molecules, both of which are essential to life. Carbon is found in all organic molecules, whereas nitrogen is an important component of nucleic acids and proteins.

  5. 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.

  6. Marine biogeochemical cycles - Wikipedia

    en.wikipedia.org/wiki/Marine_biogeochemical_cycles

    On land most phosphorus is found in rocks and minerals. Phosphorus-rich deposits have generally formed in the ocean or from guano, and over time, geologic processes bring ocean sediments to land. Weathering of rocks and minerals release phosphorus in a soluble form where it is taken up by plants, and it is transformed into organic compounds.

  7. Coal - Wikipedia

    en.wikipedia.org/wiki/Coal

    Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams.Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. [1]

  8. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System.

  9. Moon rock - Wikipedia

    en.wikipedia.org/wiki/Moon_rock

    The main repository for the Apollo Moon rocks is the Lunar Sample Laboratory Facility at the Lyndon B. Johnson Space Center in Houston, Texas. For safekeeping, there is also a smaller collection stored at White Sands Test Facility in Las Cruces, New Mexico. Most of the rocks are stored in nitrogen to keep them free of moisture.