Microcosm studies

Wilson BH, Smith GB, Rees JF. 1986. Biotransformations of seleeted alkylbenzenes and halogenated aliphatie hydrocarbons in methanogenic aquifer material A microcosm study. Environmental Science and Technology 20 997-1002. 

Yoshida N, N Takahashi, A Hiraishi (2005) Phylogenetic characterization of polychlorinated-dioxin-dechlorinating microbial community by use of microcosm studies. Appl Environ Microbiol 71 4325-4334. 

For many exogenous organisms, many of these issues will already have been established, so that only complementation will be required for indigenous organisms determination of their presence, number, and metabolic activity by conventional laboratory procedures. It may be valuable to set up enrichment cultures using site material to provide suitable material for laboratory and microcosm studies. 

Field Applicability Testing (FAT) Workshop. In March 1982, the EPA Office of Research and Development convened a workshop with the specific objectives to (1) assess the state of knowledge on determining the field applicability of laboratory bioassay tests, toxicity studies, microcosm studies, and mathematical chemical exposure models (i.e., the extent to which these methods have been tested/compared with field data), and (2) recommend research objectives and priorities to advance the current level of field testing. Workshop attendees included representatives from EPA research laboratories, universities, and private industry. 

Wilson, B.H., Smith, G.B., Rees, J.F. (1986) Biotransformations of selected alkylbenzenes and halogenated ahphatic hydrocarbons in methanogenic aquifer material A Microcosm Study. Environ. Sci. Technol. 20, 997-1002. 

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... 

Nijenhuis I, Nikolausz M, Koth A, Felfoldi T, Weiss H, Drangmeister J, GroBmann J, Kastner M, Richnow H-H (2007) Assessment of the Natural Attenuation of Chlorinated Ethenes in an Anaerobic Contaminated Aquifer in the Bitterfeld/Wolfen Area Using Stable Isotope Techniques, Microcosm Studies and Molecular Biomarkers. Chemosphere 67 300... 

The alternative explanation for the phenomenon is that bacterial communities respond physiologically to changes in DOM inputs rather than by replacing populations. Bacteria obviously have some capacity to physiologically adapt, but their reservoir of genetic information is limited, and fundamental parameters such as uptake rates and substrate affinities are determined by cell size and enzyme structure, which may be difficult to modulate. Microcosm studies suggest that changes in productivity and enzyme kinetics measured 24-48 h after DOM amendment are associated with displacements in community composition as measured by DNA comparison techniques (see Chapter 14). 

Surface water t,/2 = 7488 to 17,280 h or 312 d to 2 yr, based on aerobic aquatic microcosm study of soil and water grab samples (Howard et al. 1991). 

Schaefers C. 2002. Community level study with copper in aquatic microcosms. Study report prepared for the International Copper Association. Smallenberg (Germany) Fraunhofer Instititute for Molecular Biology and Applied Ecology, 119 p. 

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