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A model for the impact of contaminants on fish population dynamics
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- Author(s) / Creator(s)
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Mathematical models have been widely applied to perform chemical
risk assessments on biological populations for a variety of ecotoxicological pro-
cesses. In this paper, by introducing a dose-dependent mortality rate function,we formulate a toxin-dependent aquatic population model that integrates mor-
tality as toxin effect in addition to considering the effects of toxin on growthand recruitment. The model describes the direct effect of toxin on popula-
tion by treating the concentration of toxin in the environment as a parameter.The model is more convenient to connect with data than traditional differen-
tial equation models that describe the interaction between toxin and popula-
tion. We analyze the positive invariant region and the stability of boundaryand interior steady states. The model is connected to experimental data via
model parametrization. In particular, we consider the toxic effects of mercury
on rainbow trout (Oncorhynchus mykiss) and obtain an appropriate range for
each model parameter. The parameter estimates are then used to illustrate the
long-time behavior of the population under investigation. The numerical results
provide threshold values of toxin concentration in the environment to keep the
population from extirpation. The findings are consistent with surface water
quality guidelines. It may be appropriate to apply our model to other species
and other chemicals of interest to consider guideline development. -
- Date created
- 2013-01-01
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- Subjects / Keywords
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- Type of Item
- Article (Draft / Submitted)