Microbes, including bacteria and fungi, are increasingly used to treat soil and water that has been polluted by waste products from large-scale animal farming as well as pollution caused by petroleum spills and the dumping of hazardous chemicals. Many of these microbes can metabolise waste products and render them harmless or even convert harmful substances to beneficial products, such as methane gas.
Biodegradation of Petroleum Products by Bacteria
An article published in the September 2010 issue of the Journal of Environmental Science investigated the ability of electrical fields to enhance the biodegradation efficiency of bacteria on petroleum products in the soil. In this study, researchers used samples of soil that contained 50 grams of petroleum for every kilogram of soil and found that a direct electrical current of 1.0 volt increased the degradation of the petroleum by 1.6 times, compared to bacteria that were not exposed to electrical fields. The study concluded that a direct electrical current can accelerate the degradation of petroleum pollution by bacteria.
Microbes Control the Ammonia Concentrations in Soil
Ammonia from urea and uric acid waste produced by large chicken farms has a tremendous impact on water and soil quality. The Journal of Environmental Quality published a study on the use of microbes to control the amounts of ammonia leached into the environment from farm waste. The authors found that the concentrations of certain types of fungus increased threefold in chicken waste when it was treated by commercially available additives to acidify the waste in hopes of controlling the ammonia going into the environment. The study concluded that uric--acid degrading fungi could significantly decrease the amounts of ammonia in waste within two weeks.
Bacterial species, such as pseudomonas, degrade pesticides in polluted bodies of water. An article in Environmental Science and Pollution Research International investigated the effects of pseudomonas on reclamation of a lake in Poland near the site of a pesticide dump by evaluating the amounts of plankton in the water. The authors used the amount of plankton as a measurement of the lake's health. The study found that increased concentrations of pseudomonas degraded pesticides much more efficiently as compared to water samples with lesser amounts of the microbe, as indicated by the increased levels of plankton in the water.
Creation of Methane Gas
A study published in Water Research evaluated the efficiency of methanogenic bacteria, or methane-producing bacteria, in converting the gas from waste from pig farms into an alternative source of methane. The authors compared several types of bacteria to determine which produced the highest yield of methane. The study found that certain strains of bacteria, called methanomicrobiales, resulted in the highest yield of methane generated from pig farm waste.