Comparison of fluometuron sorption to soil from a filter strip and cropped field

Abstract

A laboratory experiment was conducted to compare the adsorption and desorption of fluometuron between two soils, one collected from an eastern gamagrass filter strip and the other from a cropped field. Fluometuron adsorption to soil collected from the filter strip was higher than to soil collected from the cropped field. K d values for fluometuron ranged from 1.9 to 3.6 for soil from a cropped area, compared with 2.9 to 5.3 for soil from the filter strip, indicating a weak to moderate binding affinity for fluometuron. The total fluometuron desorbed ranged from 48 to 79% of that adsorbed, most of which (50 to 59% of the total amount desorbed) occurred during the first desorption cycle with both soils. Approximately 11% less fluometuron desorbed when a filter strip was present. Results indicate that eastern gamagrass filter strips can influence adsorption–desorption processes between fluometuron and a Brooksville silty clay soil by altering the soil properties, specifically soil organic matter.

Adsorption and Desorption of Metolachlor and Metolachlor Metabolites in Vegetated Filter Strip and Cultivated Soil

“…In this study, higher OC in the VFSS compared with CS probably contributed to enhanced metolachlor sorption (Benoit et al, 1999; Blanche et al, 2003; Rankins et al, 2002; Staddon et al, 2001). Greater herbicide sorption to VFSS than CS has been reported for several herbicides including metolachlor (Staddon et al, 2001), isoproturon (Benoit et al, 1999), and fluometuron (Blanche et al, 2003; Rankins et al, 2002). Since herbicide sorption is generally inversely correlated with mobility, greater metolachlor sorption to the VFSS should reduce its mobility (Mersie et al, 1999; Staddon et al, 2001).…”

“…The K fdes value for metolachlor was 37% higher in VFSS compared with CS. Similarly, larger K fdes values were reported for metolachlor (Staddon et al, 2001), isoproturon (Benoit et al, 1999), and fluometuron (Blanche et al, 2003; Rankins et al, 2002) in VFSS compared with CS. In these experiments, higher K fdes values were attributed to the greater OC of the VFSS.…”

“…Similarly, greater atrazine (Dozier et al, 2002), metolachlor (Dozier et al, 2002), and fluometuron (Blanche et al, 2003) adsorption has been reported for bermudagrass (Dozier et al, 2002) and switchgrass (Blanche et al, 2003) thatch compared with CS (Dozier et al, 2002; Blanche et al, 2003) and VFSS (Blanche et al, 2003). In these experiments, metolachlor (Staddon et al, 2001), isoproturon (Benoit et al, 1999), and fluometuron (Rankins et al, 2002) desorption was greater for CS than VFSS.…”

“…Organic matter significantly affects herbicide sorption. Greater metolachlor (Staddon et al, 2001), fluometuron (Rankins et al, 2002; Blanche et al, 2003), and isoproturon (Benoit et al, 1999) sorption has been reported for VFSS compared with CS. Similarly, greater atrazine (Dozier et al, 2002), metolachlor (Dozier et al, 2002), and fluometuron (Blanche et al, 2003) adsorption has been reported for bermudagrass (Dozier et al, 2002) and switchgrass (Blanche et al, 2003) thatch compared with CS (Dozier et al, 2002; Blanche et al, 2003) and VFSS (Blanche et al, 2003).…”

“…By design, vegetated filter strips accumulate greater above‐ and belowground organic matter compared with adjacent cultivated soils (CS) (Benoit et al, 1999; Blanche et al, 2003; Rankins et al, 2002; Staddon et al, 2001). Organic matter significantly affects herbicide sorption.…”