Influence Of Commercial And Organic Waste Amendments On Metalaxyl Soil Sorption

The influence of two commercial humic amendments of agricultural origin (LF and SF) and the amendment with a solid waste from the olive oil processing industry (A) on metalaxyl soil sorption was assessed. Three soils of different physiochemical properties were treated with 10 YO w/w organic amendment and sorption studies performed by batch equilibration procedure. In order to examine the influence of sorption on leaching, metalaxyl was applied to the top of 30 x 5 cm methacrylate handpicked soil columns and leached under saturated/unsaturated flow conditions. For the three soils, addition of SF and A products increased sorption of metalaxyl, but in the case of LF, sorption remained unaffected or slightly decreased, which has been attributed to competition of dissolved organic matter for soil sorption sites. Laboratory leaching studies with B7, B7+LF and B7+SF confirmed sorption behaviour and indicated earlier breakthrough in soils amended with LF than in unamended soil, whereas in the case of SF leaching was reduced.