Extrapolating from local to regional effects of chemical stressors:
Combining distributed population models with realistic spatio-temporal pesticide exposure patterns
Andreas Focks, Postdoc, Wageningen University, The Netherlands
Contact: Enable-Javascript@To-Read-E-mail-Address
This project investigates if and how effects of chemical stressors on populations and the population recovery differs between local and regional (i.e. larger scale) model simulations. The final aim is to analyse how characteristics of the chemical stressors, the landscape and the species influence the recovery of affected species at the regional scale and to develop appropriate indicators addressing the risk of chemical stressors at a regional scale.
Specific Hypotheses to be Tested/Questions to be Addressed:
- Would local reproduction or different modes of dispersal (walking, swimming, drift, aerial) determine recovery on a regional scale after disturbance?
- How do different chemical fate properties and herewith exposure patterns relate to the effects and the recovery from effects?
- How do differences in landscape infrastructure (ecological connectivity) influence the recovery at the regional scale?
- Which species, landscape and chemical traits are appropriate ecological, infrastructural and stressor indicators for risks and effects of pesticides on a regional scale?
Approach to be Used:
The overall plan is to use chemical fate simulations in stream/ditch/river networks as exposure pattern in effects simulations with NetLogo/MASTEP models. Special consideration will be paid on the chemical side to the influence of pesticide properties on the magnitude and duration of effects, and on the biological side on the influence of species traits and landscape properties on effects and recovery. On a technical level, the fate simulations will be done as separated module (e.g. with CASCADE-TOXSWA) and the effects models on a regional scale will be realised via the Java API of NetLogo.
Expected Significance of the Results:
The project is positioned in the process of extrapolating chemical effects from a laboratory scale to real-world scales in terms of agricultural landscapes. The significance of my results will be to see if and how effects of chemicals on populations and their recovery differs between local and regional population models. When there will be differences, the developed indicators will enable to consider the findings for higher tier chemical risk assessment. The used methodology will ensure to identify decisive factors for possible chemical risks, e.g. chemical persistence or toxicity, time point of application, river network properties, species traits, so the results will be useful for risk mitigation strategies.
Supervisor: Paul van den Brink (Wageningen University)
Co-supervisor: Colin Brown (UYORK)
Associated partners: Bayer; UBA
