Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
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],
Year Published 1982
Report Number EPA-R-806161; EPA-600/3-82-030
Stock Number PB82-196916
OCLC Number 48499525
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
Library Call Number Additional Info Location Last
EKCD  EPA-600/3-82-030 CEMM/GEMMD Library/Gulf Breeze,FL 07/17/2018
NTIS  PB82-196916 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 01/01/1988
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.