Ecological Modeling in Risk Assessment - Chapter 8 doc

... practical. Indeed, food-web models have already been applied in basic ecological research and chemical risk assessments (Tables 8. 2 and 8. 3). On the basis of our evaluation (Table 8. 2), we recommend ... generally interacts with other species in feeding relationships, either feeding on other species, being fed upon by other species, or both. Second, a receptor of concern in...

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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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... Crassulacean acid- dependent succulents) Semi-arid rangeland in Texas and Colorado; user-defined Hanson et al. (1 988 ) Island Multi-timescale community dynamics User-defined avian species User-defined ... capabilities include forecasting vegetative structure, assessing wildlife habitat, analyzing fire hazard, determining forest health risk, and monitoring ecological processes. Usi...

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... Number 1-5 667 0-5 7 4-6 Library of Congress Card Number 20010 382 78 Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Printed on acid-free paper Library of Congress Cataloging -in- Publication ... of expressing risk from the output of a population model are discussed later in this chapter (see Steps in Ecological Modeling for a Chemical Risk Assessment,...

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... results include risk of extinction, risk of decline, time to extinction, time to decline, expected abundance, and expected variation in abundance. The model has several parameters (e.g., carrying ... 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 structured...

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... endpoints included in the 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 ... 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 organ...

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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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... 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-web models, founded ... 2 Endpoints: Expected future abundance, risk of decline in abundance, risk of extinction, time to extinction, time to decline, toxicant concentration in the environment, toxican...

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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 ... limiting factor. The third trade-off is between integrating existing models and creating new models (Fig- ure 14.1). Integrating existing models results in models with enhanced c...

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... 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 19 98) . Indeed, incorporation of simple, scalar population modeling into...

Ngày tải lên: 11/08/2014, 09:21