Assessing pesticide concentrations and fluxes in the stream of a small vineyard catchment – Effect of sampling frequency

Abstract

This study reports on the occurrence and behaviour of six pesticides and one metabolite in a small stream draining a vineyard catchment. Base flow and flood events were monitored in order to assess the variability of pesticide concentrations according to the season and to evaluate the role of sampling frequency on the evaluation of fluxes estimates. Results showed that dissolved pesticide concentrations displayed a strong temporal and spatial variability. A large mobilisation of pesticides was observed during floods, with total dissolved pesticide fluxes per event ranging from 5.7x10(-3) g/Ha to 0.34 g/Ha. These results highlight the major role of floods in the transport of pesticides in this small stream which contributed to more than 89% of the total load of diuron during August 2007. The evaluation of pesticide loads using different sampling strategies and method calculation, showed that grab sampling largely underestimated pesticide concentrations and fluxes transiting through the stream.

Variations of periphytic diatom sensitivity to the herbicide diuron and relation to species distribution in a contamination gradient: implications for biomonitoring

“…For the highest concentrations (i.e. 4.5, 13.5 and 40.5 mg L À1 ), 10 mL of a diuron-d 6 (Dr Ehrenstorfer GmbH, Augsburg, Germany) solution (1 ng mL À1 ) were added as an internal standard and the samples were only filtered with regenerated cellulose membranes (0.45 mm) (Whatman, Versailles, France) prior to the liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis. Regarding the lowest concentration (i.e.…”

“…[16][17][18] Diuron was identified as one of the major contaminants in the river. 6 This study focused on an upstream site (Saint Joseph) not impacted by agriculture and a highly polluted downstream site (Saint Ennemond) (Fig. 1).…”

“…[2][3][4][5] As plants, diatoms may be particularly sensitive to herbicides which are commonly found in rivers draining agricultural areas with peak concentrations in spring after field application and rain events. 6 Diuron (3,4-dichlorophenyl)-1,1-dimethylurea is a herbicide which belongs to the phenylurea class. It is used in agriculture and especially vineyards to control undesirable weed growth.…”

Environmental Risks of Fungicides Used in Horticultural Production Systems

“…In both studies the readily available fraction of the Cu in sediment/suspended sediment was < 5% and often < 1% of the total Cu (Ribolzi et al, 2002;Fernandez-Calvino et al, 2008). Several recent studies have also studied the movement of synthetic organic fungicides by surface run-off in catchments dominated by viticultural/horticultural production (Hildebrandt et al, 2008;Gregoire et al, 2010;Rabiet et al, 2010). The largest of these studies involved monitoring concentrations of seven fungicides in surface water collected following 58 run-off events (over four years) in a wine-growing catchment in France (Gregoire et al, 2010).…”

Structural and Functional Effects of Herbicides on Non-Target Organisms in Aquatic Ecosystems with an Emphasis on Atrazine

“…There are extensive monitoring networks for herbicides to determine spatial and temporal trends in concentrations and loads in surface waters in the U.S. Plans for implementation of monitoring networks in Europe are planned over the next 5 years in association with the www.intechopen.com REACH legislation and the European Commission (Rabiet et al, 2010). The U.S. Geological Survey monitors herbicide concentrations at over 112 monitoring stations on a regular basis as part of its National Water Quality Assessment (NAWQA) and National Stream Quality Accounting Network (NASQAN) programs.…”