Special Session - Landscape ecological modeling and ecological risk assessment: at the cross roads Chair(s): Cole, Marlene¹, Johnson, Alan ², Linkov, Igor¹, ¹ ICF Consulting, Lexington, MA² Clemson University, Clemson, SC
Wednesday, March 31, 2004 1:00 PM - 4:40 PM Apollo Room 1

Landscape ecological modeling and ecological risk assessment are often used to support environmental decision making. While each operates within its own set of methods and tools, decision-making may benefit from the fusion of the two disciplines. This session will bring together researchers involved in landscape ecological analyses and spatially explicit ecological risk assessments. Ecological risk assessment, which has much regulatory utilization and guidance, provides a systematic approach to predict the likelihood of undesired effects arising from environmental stressors. Stressors may include chemical contaminants or other ecological disturbances (land use changes, altered hydrology, invasive species, genetically modified organisms, climate change, etc.). Landscape-level approaches could benefit ecological risk assessment in a number of ways, including: (1) explicit consideration of scale and spatial organization during problem formation, (2) accounting for spatial heterogeneity in exposure characterization, (3) extrapolation from small-scale studies to broad-scale effects, (4) selection of appropriate assessment and measurement endpoints, (5) spatial analysis of uncertainties, and (6) the use of maps or other spatial visualization techniques for risk communication. In turn, ecological risk assessment can benefit landscape ecology because: (1) it has an existing regulatory presence (and is often required), (2) its framework lends itself to addressing environmental questions, and (3) it provides direct application to environmental decision making.

Wildlife risk assessment and population viability in dynamic landscapes. Andersen, Mark^*,1, ¹ Department of Fishery and Wildlife Sciences, Las Cruces, NM, USA

ABSTRACT- Explicit consideration of spatial factors is essential for effective environmental risk assessment under most circumstances. However, the quality of the habitats of any species is likely to change across the landscape and over time. This dynamic will in turn influence the exposure of any species of concern to any localized stressor, such as land-use practices, invasive species, etc. In addition landscape dynamics will influence the population dynamics of the species, as well as its population-level responses to any stressors. Thus, the interaction of landscape dynamics and population dynamics will affect both the exposure of a species to localized stressors and the effects of those stressors. I present a modeling framework that allows these issues to be examined in detail; the basic model is a coupled map lattice in a spatiotemporally fractal landscape. I also present some results motivated by an example based on an assessment of the potential impacts of an invasive species. The results illustrate the dependence of population dynamics on landscape dynamics, particularly on the fractal characteristics of the spatial and temporal components of landscape dynamics. Additional potential applications and data-quality issues are discussed. The coupled map lattice framework has the potential to provide both broad theoretical insights and specific applications.

KEY WORDS: land use, risk assessment, invasive species, coupled map lattice, spatiotemporal fractal