Source Cycle
A majority of organic matter not already in the soil comes from groundwater. When the groundwater saturates the soil or sediment around it, organic matter can freely move between the phases. Groundwater has its own sources of natural organic matter also:
- "organic matter deposits, such as kerogen and coal
- soil and sediment organic matter
- organic matter infiltrating into the subsurface from rivers, lakes, and marine systems"
Note that one source of groundwater organic matter is soil organic matter and sedimentary organic matter. The major method of movement into soil is from groundwater, but organic matter from soil moves into groundwater as well. Most of the organic matter in lakes, rivers, and surface water areas comes from deteriorated material in the water and surrounding shores. However, organic matter can pass into or out of water to soil and sediment in the same respect as with the soil.
Read more about this topic: Organic Matter
Famous quotes containing the words source and/or cycle:
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