The Basic Principles of Decomposition

Organic materials have many different qualities and uses. Yet all organic materials have a common trait that sets them apart from other materials: they naturally decompose. Decomposition is nature's way of recycling organic matter to replenish the soil and nourish plant growth.

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Anaerobic Decomposition and Methane Production

In some situations, such as human-engineered landfills, decomposition can create serious problems. When buried, organic materials are cut off from air and decompose very slowly-even newspapers from 40 years ago can still be found relatively intact in landfills.

Decomposition in the absence of air-or anaerobic decomposition-produces methane gas. Methane can build up in landfills or migrate underground to nearby buildings, creating the danger of explosion. As rain or groundwater percolates through the landfill, weak acids produced by decaying organic matter wash through the landfill and react with the other trash, creating a potentially toxic leachate that can contaminate groundwater, lakes, and streams. The systems designed to capture methane gas and collect leachate make landfills expensive to build and operate.

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Managed Decomposition: Composting

When organic materials are separated from trash and allowed to decompose with an adequate amount of oxygen-or aerobically-they can be turned into compost, a valuable resource. When used in gardens and parks, compost helps to make soil loose and well-drained, provides plants with valuable nutrients, protects soil from erosion and compaction, and conserves water and other resources.

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ALSO SEE:
how does compost happen?
chemical decomposers-microorganisms
physical decomposers-larger organisms