|Persistence in model ecosystems /
Gard, T. C.
| U.S. Environmental Protection Agency, Research and Development, Environmental Research Laboratory Center for Environmental Research Information [distributor],
|EPA/600-S3-82-030; EPA-600/3 S-82-030
Closed ecological systems--Mathematical models
|In Binder Received from HQ
| pages ; 28 cm
|Caption title. At head of title: Project summary. "May 1982." "EPA/600-S3-82-030."
|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 and sufficient conditions for continued presence of the model components throughout indefinite time intervals. These results can serve as a basis for preliminary evaluations of model performance.
|Corporate Au Added Ent
|Environmental Research Laboratory (Athens, Ga.)
|PUB Date Free Form
|OCLC Time Stamp
|EP 1.89/2:Ec 7
|OCLC Rec Leader
|02012cam 2200313Ia 45020