Author
AZCARATE, PAMELA - Instituto Nacional Tecnologia Agropecuaria | |
Schneider, Sharon | |
MONTOYA, JORGELINA - Instituto Nacional Tecnologia Agropecuaria | |
Koskinen, William |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 5/7/2014 Publication Date: 8/10/2014 Citation: Azcarate, P., Papiernik, S.K., Montoya, J., Koskinen, W.C. 2014. Sorption-desorption of rimsulfuron, nicosulfuron, and their metabolites in soils from Argentina and USA. 13th IUPAC International Congress of Pesticide Chemistry, August 10-14, 2014, San Francisco CA. Abstract 474. Interpretive Summary: Technical Abstract: For many pesticides, sorption coefficients increase with residence time in the soil, becoming constant after weeks of aging in the soil. Pesticide sorption is often slowly reversible with some fraction being recalcitrant to desorption. Dissipation in soil often follows a biphasic trend, in which the rate of degradation decreases with increasing residence time in the soil. These dynamic processes are ignored or simplified in many models describing pesticide fate and transport in soil. In more complex models, these processes are treated using multi-compartment models, non-first-order kinetic models, and other approaches. We surmise that a more straightforward approach to describing the dynamics of pesticide biodegradation in soil would consider bioavailability as linked to changes in sorption with residence time in soil. We describe here some examples of this approach for pesticides showing different trends in time-dependent sorption. |