1. Department of Environment and Geography, University of York, Heslington, York, YO10 5NG, U.K.
2. UK Centre for Ecology and Hydrology, Maclean Building, Benson Lane, Wallingford OX10 8BB, Oxfordshire, U.K.
3. DEBtox Research, Stevensweert 6107, The Netherlands
4. Syngenta Crop Protection AG, Basel 4058, Switzerland