TA9 Ecological Risk Assessment and Landscape Ecological Modeling
D137-140
8:00 AM - 12:00 PM, Tuesday
() Landscape-scale behavioural-based models of vertebrates for population-level risk assessment.
Topping, C1, 1 EcoSol, Rønde, Denmark
ABSTRACT- Behavioral models have a number of advantages when used for impact assessment. Their precise modeling of the location of animals in space and time, as well as the ability to model the physiological state of individuals means that the impact of a toxicant or management can be precisely modeled at the individual level. It is now possible to combine these models with comprehensive landscape simulations capable of simulation field management and non-cropped areas simultaneously, resulting in highly realistic models. This provides the potential for evaluating a range new factors rarely considered in current risk assessments. One of the primary benefits for pesticide risk assessment is that the pattern of usage of the compound in both space and time can be modeled by these systems. Other potential influences that can be considered include modeling multiple stressors, and indirect effects. Here I present two examples of the use of these models in risk assessment of pesticides in Northern Europe. The first example considers the indirect effect of pesticides on three species of farmland bird, and considers what the impact of a national Danish scheme to reduce the amount of pesticides. The aim of the Danish scheme was to reduce the average number of pesticide applications per crop from its starting value of 2.3 down to 2.0 and then further to 1.7. Simulation results suggested that the impact of this reduction was negligible due to the confounding factor of the efficiency of modern farming. The second example is of a fictitious pesticide causing sterility of field voles. In this case I compare the effect of pesticide-induced sterility to the same proportion of voles suffering mortality. It is argued that the mortality scenario is analogous to a traditional population approach, and that the landscape-scale model has significant advantages when describing this type of system.
Key words: Risk assessment, Agent-based model, Landscape simulation