Soil Core Microcosm

In a soil-core microcosm study, Winkelmann and Klaine (1991) observed that the concentration of atrazine decreased exponentially over a 6-month period. Metabolites identified in soil included desethylatrazine, deisopropylatrazine, didealkylatrazine, and hydroxyatrazine. The half-life in soil... 

Winkelmann, D.A. andKlaine, SJ. Atrazine metabolite behavior in soil-core microcosms, in Pesticide Transformation Products. Fate and Significance in the Environment, ACS Symposium Series 459, Somasundaram, L. and Coats, J.R., Eds. (Washington, DC American Chemical Society, 1991), pp. 75-92. 

US Environmental Protection Agency [USEPA]. 2002a. Terrestrial (soil-core) microcosm test guideline. Washington (DC) US Environmental Protection Agency. 

Conducting Static Toxicity Tests with the Lemma gibba G3 Conducting a Terrestrial Soil-Core Microcosm Test Conducting Three-Brood, Renewal Toxicity Tests With Ceriodaphnia dubia Hazard of a Material to Aquatic Organisms and Their Uses... 

Terrestrial Microcosms Root Microcosm System Soil Core Microcosm Soil in a Jar... 

Terrestrial microcosms also see a comparable range in size and complexity. A microbial community living within the soil in a test tube can be used to examine biodegradation. A soil core is comparable in size and utility to the laboratory microcosms described above. In some cases terrestrial microcosms can be established with a variety of plant cover and include small mammals and insects. Field plots are the terrestrial equivalent of the larger outdoor... 

Survey and Review of Typical Toxicity Test Methods 4.3.4 Soil Core Microcosm... 

The soil core microcosm (SCM) is one of the first test vehicles developed for the evaluation of xenobiotics on an agroecosystem with it accompanying plants, soil invertebrates, and microbial processes. Table 4.16 summarizes the basic protocol. 

Summary of Test Conditions for Conducting a Terrestrial Soil-Core Microcosm Test... 

Microcosm size and type 60-cm deep X 17-cm diameter plastic pipe made of ultra-high molecular weight, high density, and nonplasticized polyethylene and containing an intact soil core covered by homogenized topsoil tube sits on a Buchner funnel covered by a thin layer of glass wool... 

ASTM E 1197-87.1993. Standard guide for conducting a terrestrial soil-core microcosm test. Annual Book of ASTM Standards. American Society for Testing and Materials, Philadelphia, PA. 

Many simple laboratory microcosms have been constructed primarily to assess the behavior of the chemical in both terrestrial and aquatic systems. Another approach has been to bring a piece of the environment into the laboratory. Soil cores have been used to monitor the fate of both inorganic and organic contaminants. A complex terrestrial microcosm will be described to illustrate what is involved in the design and operation of such a unit and the nature of the data generated. 

Winkelmann DA, KlaineSJ (1991) Atrazine metabolite behavior in soil-core microcosm formation, disappearance, and bound residues. Pesticide transformation products in the environment. In Somasundaram L, Coats JR (eds) Pesticide Transformation Products Fate and Significance in the Environment. American Chemical Society, Washington DC, pp 75-92... 

In a soil-core microcosm study, Winkelmann and Klaine (1991) observed that the concentration of atrazine decreased exponentially over a 6-month period. Metabolites identified in soil included DEA, deisopropylatrazine, DAA and hydroxyatrazine. The half-life in soil is 71 days (Jury et al., 1987). Under laboratory conditions, the half-lives for atrazine in a Hatzenbiihl soil (pH 4.8) and Neuhofen soil (pH 6.5) at 22°C were 53 and 113 days, respectively (Burkhatd and Guth, 1981). Atrazine degradation products identified in soil were deethylatrazine, deisopropylatrazine, deethyldeisopropylatrazine and hydroxyatrazine (Patumi et al., 1981). Microbial attack of atrazine gave deethylated atrazine and deisopropyl atrazine as major and minor metabolites, respectively (Sirons et al., 1973). 

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