Comparison of Microbial Transformation Rate Coefficients of Xenobiotic Chemicals Between Field-Collected and Laboratory Microcosm Microbiota


Book Description

Two second-order transformation rate coefficients--kb, based on total plate counts, and kA, based on periphyton-colonized surface areas--were used to compare xenobiotic chemical transformation by laboratory-developed (microcosm) and by field-collected microbiota. Similarity of transformer to nontransformer community structure in blended aufwuchs was indicated by kb values, and similarity of transformation rates per unit of periphyton-colonized surface area was indicated by kA values. Xenobiotic chemicals used for the comparisons were methyl parathion (MP), diethyl phthalate (DEP), and 2,4-dichlorophenoxyacetic acid butoxyethyl ester (2,4-DBE). Even though rate coefficients of each of the chemicals were similar among microcosm- and field-collected microbial samples, not all of the field-collected samples showed MP or DEP transformation. The MP transformation was suppressed by aqueous extracts of field-collected, algae-dominated aufwuchs. Lack of DEP transformation appeared to have resulted from an absence of DEP-transforming bacteria in field-collected aufwuchs samples.










Ecological Microcosms


Book Description

Ecological Microcosms is a seminal work which reviews the expanding field of enclosed ecosystem research, and relates the results and models of microcosm studies to general concepts in ecology. Microcosms are miniaturized pieces of our biosphere, ranging from streams and lakes to terraria, agroecosystems, and waste systems. The study of these simplified ecosystems is providing provocative insights into ecological principles as well as issues of environmental management and global stability. The authors have used the well-known thermodynamic approach of H.T. Odum and numerous computer simulations. The book also includes an evaluation of alternative mesocosm approaches for the support of humans in space, as well as appendices to aid in the teaching of environmental concepts using student-created microcosms. Ecological Microcosms will be of interest to ecologists, environmental engineers, policy makers and environmental managers, space scientists, and educators. Robert J. Beyers is a Professor of Biology at the University of South Alabama. Howard T. Odum is Graduate Research Professor of Environmental Engineering Sciences at the University of Florida, and was awarded, with Eugene Odum, the 1987 Crafoord Prize in the Biosciences.







EPA's Sludge Rule


Book Description










Handbook of Ecotoxicology


Book Description

The Handbook of Ecotoxicology provides a readily accessible, yet critical collection of information on ecotoxicological testing. Now available in a single paperback volume, this handbook represents excellent value. Part A concentrates on techniques, especially those tests used for prediction. Thorough descriptions of the main tests are provided, followed by critical analyses in terms of ease of handling, repeatability and ecological relevance, and finally, an extensive bibliography citing key documents describing test methods and key papers evaluating them. Part B focuses on the toxicants themselves: summarising their ecological effects, describing ways of predicting effects from physico-chemical properties alone, and describing and discussing fate models. Now available as a single volume in paperback An invaluable reference resource