Bioremediation

Bioremediation can be defined as any process that uses microorganisms, fungi, green plants or their enzymes to return the environment altered by contaminants to its original condition. Bioremediation may be employed to attack specific soil contaminants, such as degradation of chlorinated hydrocarbons by bacteria. An example of a more general approach is the cleanup of oil spills by the addition of nitrate and/or sulfate fertilisers to facilitate the decomposition of crude oil by indigenous or exogenous bacteria.
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Noun
1. the branch of biotechnology that uses biological process to overcome environmental problems
(hypernym) biotechnology
2. the act of treating waste or pollutants by the use of microorganisms (as bacteria) that can break down the undesirable substances
(hypernym) treatment, handling
(classification) bacteria, bacterium

Use of living organisms to clean up oil spills or remove other pollutants from soil, water, or wastewater; use of organisms such as non-harmful insects to remove agricultural pests or counteract diseases of trees, plants, and garden soil.