Record Display for the EPA National Library CatalogRECORD NUMBER: 11 OF 17
|Main Title||Persistence in model ecosystems /|
|Author||Gard, T. C.|
|CORP Author||Georgia Univ., Athens. Dept. of Mathematics.;Environmental Research Lab., Athens, GA.|
|Publisher||U.S. Environmental Protection Agency, Research and Development, Environmental Research Laboratory Center for Environmental Research Information [distributor],|
|Report Number||EPA-R-806161; EPA-600/3-82-030|
|Subjects||Closed ecological systems--Mathematical models.|
|Additional Subjects||Ecology ; Food chains ; Nutrients ; Water pollution ; Mathematical models ; Toxicity ; Algae ; Aquatic biology ; Marine biology ; Periodic variations ; Environmental impacts ; Organic compounds ; Differential equations ; Evaluation ; Ecosystems|
|Collation||17 pages ; 28 cm|
Mathematical models aid in understanding environmental systems and in developing testable hypotheses relevant to the fate and ecological effects of toxic substances in such systems. Within the framework of microcosm or laboratory ecosystem modeling, some differential equation models, in particular, become tractable to mathematical analysis when the focus is on the problem of persistence. In this report, a hierarchy of microcosm-related models, the top level of which contains a nutrient-producer-grazer food chain, and general food chains are analyzed for persistence. The results, which take the form of inequalities involving model parameters, specify necessary conditions. These results can serve as a basis for preliminary evaluations of model performance.
Caption title. "April 1982." "EPA-600/3-82-030." Microfiche.