Ecological Modeling in Risk Assessment - Chapter 13 pdf

... development and use are shown in Tables 13. 2 through 13. 7. Toxicity extrapolation models are intended mainly for use in screening-level risk assessments and for developing generic environmental ... discrete or continuous- time) and deterministic life-history matrix models are most appropriate for screening-level ecolog - ical risk assessments (Table 13. 1). Some simple food...

Ngày tải lên: 11/08/2014, 09:21

... assessing the significance of estimated risks initially expressed in terms of individual-level end - points. In this mode, ecological models aid in translating risks for individual-level endpoints ... cost-effective approach for addressing many risk assessment issues (Ferson et al. 1996; Barnthouse 1998). Indeed, incorporation of simple, scalar population modeling into sc...

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... applied in this way. So far, we have discussed the use of ecological modeling in evaluating the ecological signifi- cance of risks to individual organisms. In addition to its use in risk characterization, ... an ecological model. Define Ecological Modeling Objectives The objectives of ecological modeling in the context of a chemical risk assessment are determin...

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... it. Relevance — HIGH — Possible endpoints include expected population size (age- or stage-specific), risk of decline, risk of extinction, and expected crossing time (the time at which the population ... is included. Relevance — HIGH — Possible endpoints include expected population size (age- or stage-specific), lambda, lambda-based measures such as sensitivity and elasticity, and risk...

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... extinction), a generic metapopulation model (Possingham and Davies 1995) • Meta-X, an occupancy status model currently being developed (UFZ and OFFIS 2000) In this chapter, we also included individual-based ... Gilpin and Hanski (1991), Breininger et al. (in press), and Akçakaya and Sjögren-Gulve (2000). We review two occupancy-type models and four software platforms for spatially struc...

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... unclear. Relevance — HIGH — Potential endpoints include the expected population size of any population in the model, risk of decline, risk of extinction, and expected crossing time (the time at which the ... collected. POPULATION-DYNAMIC FOOD-CHAIN MODELS These models are constructed by using predator–prey models (in differential equation form) with equations modeling the dynamics...

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... model are relevant to ecological risk assessment. The examination of direct and indirect effects of stressors (e.g., entrain - ment) is of high interest in ecological risk assessment. Although ... LEEM was initiated by the International Joint Commission to aid in anticipating the effects of declining nutrient loading, invasion of zebra mussels, loading of toxic organic con...

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... capabilities include forecasting vegetative structure, assessing wildlife habitat, analyzing fire hazard, determining forest health risk, and monitoring ecological processes. Using a parallel processing ... developing silvicultural prescriptions, evaluating management scenar - ios, updating inventory information, and providing input to forest planning models (USDA 1999 and reference...

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... modeling (Nestler 2001, pers. comm.). The modeling strategy inherent in CEL HYBRID has subtle problems in maintaining conser- vation when any sources or sinks are present and a problem with inflation ... the biology. An individual-based population model is a specific example of the broader CEL HYBRID approach to modeling. What individual-based modeling does for population modelin...

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... INVESTMENT TRADE-OFFS Investments in enhancing the use of ecological models in environmental decision-making involve three trade-offs represented by the diamond-shaped boxes in Figure 14.1 (Ginzburg ... Akçakaya (in press). Science and management investments needed to enhance the use of ecological modeling in decision-making. In V. Dale, Ed., Ecological Modeling for...

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