Simulation of herbicide impacts on a plant community: comparing model predictions of the plant community model IBC-grass to empirical data

Authored by Jette Reeg, Simon Heine, Christine Mihan, Sean McGee, Thomas G Preuss, Florian Jeltsch

Date Published: 2018

DOI: 10.1186/s12302-018-0174-9

Sponsors: German Research Foundation (Deutsche Forschungsgemeinschaft, DFG)

Platforms: No platforms listed

Model Documentation: Other Narrative Flow charts Mathematical description

Model Code URLs: Model code not found

Abstract

BackgroundSemi-natural plant communities such as field boundaries play an important ecological role in agricultural landscapes, e.g., provision of refuge for plant and other species, food web support or habitat connectivity. To prevent undesired effects of herbicide applications on these communities and their structure, the registration and application are regulated by risk assessment schemes in many industrialized countries. Standardized individual-level greenhouse experiments are conducted on a selection of crop and wild plant species to characterize the effects of herbicide loads potentially reaching off-field areas on non-target plants. Uncertainties regarding the protectiveness of such approaches to risk assessment might be addressed by assessment factors that are often under discussion. As an alternative approach, plant community models can be used to predict potential effects on plant communities of interest based on extrapolation of the individual-level effects measured in the standardized greenhouse experiments. In this study, we analyzed the reliability and adequacy of the plant community model IBC-grass (individual-based plant community model for grasslands) by comparing model predictions with empirically measured effects at the plant community level.ResultsWe showed that the effects predicted by the model IBC-grass were in accordance with the empirical data. Based on the species-specific dose responses (calculated from empirical effects in monocultures measured 4weeks after application), the model was able to realistically predict short-term herbicide impacts on communities when compared to empirical data.ConclusionThe results presented in this study demonstrate an approach how the current standard greenhouse experimentsmeasuring herbicide impacts on individual-levelcan be coupled with the model IBC-grass to estimate effects on plant community level. In this way, it can be used as a tool in ecological risk assessment.

Tags

Individual-based modeling pattern Traits European flora Plant community model Non-target terrestrial plants Community-level effects Herbicide risk assessment Glyphosate