FELS: A comprehensive approach to studying the fate of pesticides in soil at the laboratory, lysimeter and field scales

Lysimeters containing a soil monolith are generally recognized and used to study the environmental behaviour of pesticides in accordance with good agr icultural practice. In order to validate the transfer of lysimeter data to the field/region scale, an extensive experiment was set up consisting of a 1-ha experimental field plot with five sampling tubes, a small plot experim ent, 12 lysimeters, a measurement trench with 102 time domain reflectometry sensors (TDR) and 21 temperature sensors and a weather station. The leacha te in the field and small-plot experiment is obtained using tensiometer-con trolled ceramic plates. In addition to a mobile and an immobile test substa nce for determining mass transport, several water tracers are used over the three-year test period. A preliminary experiment for the further character ization of the test site and test systems was started in March 1997 with th e application of 2,6-difluorobenzoic acid. Complementary laboratory studies are performed for process identification and generation of input parameter s for simulation models.