Microorganisms in soil

The most complex of the feedback systems are those in which biota are directly involved. Indeed, one feedback of climate on CH4 may well be an example microorganisms in soils are a known CH4 sink, and the rate at which they consume CH4 is temperature dependent. 

There have been some reports of herbicides disturbing the metabolism of microorganisms in soil. For example, dichlobenil was shown to increase the rate of CO2 formation from glucose in soil (Somerville and Greaves 1987). 

Commercially produced amines contain Impurities from synthesis, thus rigid specifications are necessary to avoid unwanted Impurities In final products. Modern-day analytical capability permits detection of minute quantities of Impurities In almost any compound. Detection In parts per million Is routine, parts per billion Is commonplace, and parts per trillion Is attainable. The significance of Impurities In products demands careful and realistic Interpretation. Nltrosatlng species, as well as natural amines, are ubiquitous In the environment. For example, Bassow (1976) cites that about 50 ppb of nitrous oxide and nitrogen dioxide are present In the atmosphere of the cities. Microorganisms In soil and natural water convert ammonia to nitrite. With the potential for nitrosamine formation almost ever-present In the envlronmeit, other approaches to prevention should Include the use of appropriate scavengers as additives In raw materials and finished products. 

Soil pH affects the transformation of Cr between Cr(III) and Cr(VI) in soils. Since Cr(VI) has greater bioavailability and mobility in soils than Cr(III), which is strongly bound by soil solid matrix (Han and Banin, 1997). Cr(III) can be oxidized by soil manganese oxides into Cr(VI), while Cr(VI) can be reduced by organic matter, Fe(II) and microorganisms in soils. Reduction of Cr(VI) has been found to occur much slower in alkaline soils compared to acid soils (Cary et al., 1997). 

Although all microorganisms in soil are important, most attention is focused on bacteria (often, little or no distinction is made between bacteria and cocci, both being lumped together and simply referred to as bacteria ). This is because they are extremely numerous and versatile in the reactions they carry out. In well-drained soils, they inhabit aerobic (oxidizing), anaerobic... 

Kuhn EP, Suflita JM. 1989. Dehalogenation of pesticides by anaerobic microorganisms in soils and groundwater-a review. In Reactions and movement of organic chemicals in soils. Soil Science Society of America Special Publication 22 111 -180. 

Soil. In soil, malathion was degraded by Arthrobacter sp. to malathion monoacid, masphoro-dithioate. After 10 d, degradation yields in sterile and nonsterile soils were 8, 5, and 19% and 92, 94, and 81%, respectively (Walker and Stojanovic, 1974). Chen et al. (1969) reported that the microbial conversion of malathion to malathion monoacid was a result of demethylation of the 0-methyl group. Malathion was converted by unidentified microorganisms in soil to thiomalic acid, dimethyl thiophosphoric acid, and diethylthiomaleate (Konrad et al, 1969). 

CASRN 25954-13-6 molecular formula C3HnN204P FW 170.10 Soil. Fosamine is rapidly degraded to carbon dioxide by microorganisms in soil (Humburg et al, 1989). The reported half-life in soil is approximately 7 to 10 d (Hartley and Kidd, 1987). 

Robert, M. Chenu, C. (1992). Interactions between soil minerals and microorganisms. In Soil Biochemistry, Vol. 7, ed. G. Stotzky J-M. Bollag, pp. 307-404. New York Marcel Dekker. 

The effect of PCDDs, PCDFs, and PCDDs on CP-degrading microorganisms in soil has not been systematically studied. These compounds do not biodegrade and do not seem to inhibit CP bioremediation (Valo Salkinoja-Salonen, 1986 McBain et al., 1995). The treatment of soils contaminated simultaneously with PAHs and chlorinated dimeric compounds by white-rot fungi could be potentially advantageous since the peroxidase enzymes oxidize all these chemicals (e.g. Valli et al., 1992 Gold et al., 1994 Lamar Glaser, 1994). 

Sjoblad, R. D., and Bollag, J.-M. (1981). Oxidative coupling of aromatic compounds by enzymes from soil microorganisms. In Soil Biochemistry, Vol. 5, Paul, E. A., and Ladd, J. N., eds., Marcel Dekker, NewYork, 113-125. 

Larkin, R.P., Hopkins, D.L., Martin, F.N. Effect of successive watermelon plantings on Fusarium oxysporum and other microorganisms in soils suppressive and conducive to Fusarium wilt of watermelon. Phytopathology 1993 83 1097-1105. 

Biodegradation slowly broken down by microorganisms in soil, in pure culture, a soil fungus metabolizes rapidly with t,/2 = 2 wk (Herbicide Handbook 1989). 

Soil. Aerobic and anaerobic microorganisms in soil decompose metaldehyde to C02 and water... 

Gorbushina, A. A. Krumbein, W. E. (2005). Role ofmicroorgansims in wear down of rocks and minerals. In Soil Biology, Vol. 3. Microorganisms in Soils Role in Genesis and Functions, ed. F. Buscot A. Varma. Berlin Springer-Verlag, pp. 59-84. 

Related Experiment in the Companion Book 22. Microorganisms in soil, water and air... 

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