Transfer of pesticides and metals in a small vineyard watershed. Preliminary study of the influence of hydrologic conditions on the transport of contaminants

Abstract

The implementation of the European water framework directive implies the intensification of contaminants monitoring, identification of the causes of degradation and implementation of corrective actions to reach a good chemical and biological status by 2015. The aim of the present study is on the one hand, to evaluate concentrations and fluxes of pesticides and metals in a small stream draining an agricultural watershed located in the Beaujolais area and on the other hand, to define a sampling strategy adapted for an accurate evaluation of exposition to these contaminants. The estimation of pesticide fluxes passing through the river during flood events and during grab sampling showed that a single flood event can transport as much pesticides as those mobilized during one month in baseflow.