TA9 Ecological Risk Assessment and Landscape Ecological Modeling
D137-140
8:00 AM - 12:00 PM, Tuesday
() Incorporation of Landscape Characteristics and Receptor Organism Movement in Spatially Explicit Exposure Assessment Model RiskTrace.
Linkov, I1, Grebenkov, A2, Andrizhievski, A2, Loukashevich, A2, Trifonov, A2, Kapustka, L3, 1 Cambridge Environmental Inc., Cambridge, MA 02141, USA2 Institute of Power Engineering, Minsk, Belarus3 ep-and-t, Corvallis, OR, USA
ABSTRACT- We will present a methodological approach and a software prototype for spatially explicit risk assessment of contaminated terrestrial ecosystems designed to be implemented as a part of a risk-based decision protocol to support the assessment of ecological value and site reuse options for such areas. The software prototype calculates chemical accumulation by a receptor organism foraging in areas with specified contamination patterns and habitat parameters. For areas containing spatially localized contaminants, the software estimates exposure levels for wildlife as functions of spatial factors, such as the organism's average foraging area, the size of the habitat being assessed, and the distribution of contamination. Species exhibiting different foraging strategies may experience significantly different chemical exposures from the same site, even if their foraging areas overlap. Currently, exposure estimates and subsequent ecological risk projections generally assume a static and continuous exposure of an organism to a contaminant concentration represented by some descriptive statistic, such as the mean or maximum concentration. These assumptions are generally overly conservative and ignore some of the major advantages offered by advanced risk assessment techniques, such as the ability to account for site-specific conditions and to conduct iterative analyses. Our spatially explicit foraging model provides a time series estimation of soil and food contamination that receptor organisms may encounter in their daily movements. The model employs habitat suitability index (HSI) model to account for differential attraction to various habitat types within the site.
Key words: spatially explicit, ecological risk assessment, habitat suitability index, HSI, software model