You are here:
LANDSCAPE-SCALE EFFECTS OF TOXIC EVENTS FOR ECOLOGICAL RISK ASSESSMENT
Citation:
Fahrig, L. AND K. Freemark. LANDSCAPE-SCALE EFFECTS OF TOXIC EVENTS FOR ECOLOGICAL RISK ASSESSMENT. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/A-93/233 (NTIS PB93236628), 1993.
Description:
The effect of spatial heterogeneity on response of organisms has rarely been considered in ecological risk assessment or in ecotoxicological studies. ncreased and widespread use of agricultural pesticides has been linked with population declines of plants, invertebrate and vertebrate species. n this chapter the authors argue that ecological risk assessments for toxicants must go beyond the current practice of only assessing effects at the spatial and temporal scales of direct impact. he objectives are (1) to extend results of the effects of landscape pattern and variability on population survival to landscape scale effects of toxic events, (2) to develop a conceptual model of landscape-scale effects of toxic events on species, and (3) to propose a practical approach for redicting when landscape-scale ffects f toxic events are likely to occur. he authors rely primarily on tudies from the general ecological literature, articularly hose n he dynamics of stochastic, spatially structured populations. They do so viewing a toxic event as just another type f cological isturbance, thus enabling them to argue by extension from the existing literature.
