Conclusion

The processes governing the transfer of pesticides in soils are extremely varied and complex. Thus, the problem of quantitative assessment of the transfer and degradation of pesticides transported by infiltration must necessarily address aspects relating to the accessibility of retention and degradation sites. These are directly linked to the location of transport processes. In these systems, the circulation routes of solutions loaded with soluble pesticides, both through the soil during infiltration and at the soil surface, play a decisive role in pesticide distribution. Water transport modalities control the location of retention and release processes. They also control sorption kinetics and the quantities actually retained in soils. One of the questions currently raised is the existence of rapid vertical flows that can carry pesticides to deep horizons, without sufficient contact with...