Pesticides, Plants and Arthropods – Using a land-use and climate gradient approach to evaluate the potential impact of agrochemicals

• Applicants: Professor Dr. Jörg Müller; Professor Dr. Ralf Schulz
• Subject Area: Ecology of Land Use
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 511569970

Pesticides have often been mentioned as a parameter contributing to species diversity in agricultural landscapes, yet their role in the distribution of non-target plants or arthropods in off-field areas is not clear. Here we propose to use existing landscape and ecological data from a well-established land-use and climate gradient across Bavaria, i.e. the ~180 LandKlif sites of the University of Würzburg. We intend here to collect additional soil, plant biomass, arthropod (herbivores and spiders) biomass samples to measure the presence of agricultural pesticides in these samples and to conduct additional collections and determinations of species groups not yet covered in LandKlif (spiders and beetles). We intend to evaluate the importance of landscape features for the pesticide exposure and aim to combine traits of pesticide exposure (identity of different mode of actions, combinations of compounds (mixture toxicity), concentration levels, compound-specific toxicity, etc.) with traits of plant and arthropod distribution in the light of the available information on various confounding factors. Using data on compound and crop-specific pesticide use we intend to contextualise our findings through a meta-analytical integration of exposure and effect data for terrestrial plants and arthropods stemming from the published literature and regulatory risk assessment documents. We anticipate that the implementation of a larger set of background data will aid interpretation of our findings on pesticide exposure and species distribution at the LandKlif sites. Through the combination of the well-established LandKlif study area and terrestrial ecology expertise with pesticide ecotoxicology and meta-analytical expertise, we hope to shed further light on the potential role of agrochemicals in terrestrial non-target ecosystems.

• DFG Programme: Research Grants