TY - JOUR A1 - Reeg, Jette A1 - Heine, Simon A1 - Mihan, Christine A1 - Preuss, Thomas G. A1 - McGee, Sean A1 - Jeltsch, Florian T1 - Potential impact of effects on reproductive attributes induced by herbicides on a plant community JF - Environmental Toxicology and Chemistry N2 - Current herbicide risk assessment guidelines for nontarget terrestrial plants require testing effects on young, vulnerable life stages (i.e., seedling emergence [and subsequent growth] and vegetative vigor [growth and dry wt]) but not directly on the reproduction of plants. However, the European Food Safety Authority (EFSA) has proposed that effects on reproduction might be considered when evaluating the potential effects on plants. We adapted the plant community model for grassland (IBC-grass) to give insight into the current debate on the sensitivity of reproductive versus vegetative endpoints in ecological risk assessment. In an extensive sensitivity analysis of this model, we compared plant attributes potentially affected by herbicides and the consequences for long-term plant population dynamics and plant diversity. This evaluation was implemented by reducing reproductive as well as vegetative endpoints by certain percentages (e.g., 10-90%) as a theoretical assumption. Plant mortality and seed sterility (i.e., inability of seeds to germinate) were the most sensitive attributes. Our results indicated that effects on seed production at off-field exposure rates must be very strong to have an impact on the risk assessment. Otherwise, effects on seed production are compensated for by the soil seed bank. The present study highlights the usefulness of community level modeling studies to support regulators in their decisions on the appropriate risk assessment endpoints and provides confidence in their assessments. Environ Toxicol Chem 2018;37:1707-1722. (c) 2018 SETAC KW - Ecological risk assessment KW - Ecotoxicology KW - Herbicide KW - Plant reproduction KW - Plant community model KW - Nontarget terrestrial plants Y1 - 2018 U6 - https://doi.org/10.1002/etc.4122 SN - 0730-7268 SN - 1552-8618 VL - 37 IS - 6 SP - 1707 EP - 1722 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Reeg, Jette A1 - Heine, Simon A1 - Mihan, Christine A1 - McGee, Sean A1 - Preuss, Thomas G. A1 - Jeltsch, Florian T1 - Simulation of herbicide impacts on a plant community BT - comparing model predictions of the plant community model IBC-grass to empirical data JF - Environmental Sciences Europe N2 - Background Semi-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. Results We 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 4 weeks after application), the model was able to realistically predict short-term herbicide impacts on communities when compared to empirical data. Conclusion The results presented in this study demonstrate an approach how the current standard greenhouse experiments—measuring herbicide impacts on individual-level—can 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. KW - Plant community model KW - Non-target terrestrial plants KW - Community-level effects KW - Herbicide risk assessment KW - Individual-based modeling Y1 - 2018 U6 - https://doi.org/10.1186/s12302-018-0174-9 SN - 2190-4715 SN - 2190-4707 VL - 30 IS - 44 PB - Springer CY - Berlin und Heidelberg ER -