chapter  6
16 Pages

The Spatial Structure of Populations and Ecological Risk Assessment

WithWayne G. Landis

The introduction of spatial considerations to the risk assessment of populations provides a number of insights and opportunities for ecological risk assessment. Many populations use only certain areas of the landscape for spawning, other areas for maturation, and adults may be segregated to an alternate part of the landscape. Several animal and plant populations have been examined in the context of understanding the influence of spatial structure on their dynamics. Metapopulation dynamics is a useful tool in evaluating the consequences of a stress over both time and space. The potential pattern of propagation of effects from the spatial relationships among populations requires an understanding of these interactions. The expansion of population-level ecological risk assessment also broadens the types of questions that can be approached. A general assumption is that there is a minimum viable population size below which patch extinction will occur in a deterministic model.