Abstract
Current herbicide risk assessment guidelines for non-target terrestrial plants require testing effects on young vulnerable life stages (i.e., seedling emergence (and subsequent growth) and vegetative vigor (growth and dry weight)) but not directly on the reproduction of plants. However, the European Food Safety Authority (EFSA) recently brought into attention that effects on reproduction might be considered when evaluating the potential effects on plants.
We adapted the plant community model IBC-grass to give insights in the current debate on the sensitivity of reproductive vs. vegetative endpoints in ecological risk assessment. In an extensive sensitivity analysis of the model, we compared plant attributes potentially affected by herbicides and the consequences for long-term plant population dynamics and plant diversity. This 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 indicate that effects on seed production at off-field exposure rates have to be very strong in order to have an impact on the risk assessment. Otherwise, effects on seed production are compensated for by the soil seed bank. This study highlights the usefulness of community level modeling studies to support regulators in their decision of the appropriate risk assessment endpoints and provide confidence in their assessment. This article is protected by copyright. All rights reserved
from Enviromental via alkiviadis.1961 on Inoreader http://ift.tt/2ERBqun
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου