Sustainable agricultural practices influence s-metolachlor, foramsulfuron and thiencarbazone-methyl degradation and their metabolites formation.

The effect of sustainable agricultural practices, such as mulching or the application of straw residues as an organic amendment, on the degradation, dissipation and persistence in the soil of S-metolachlor (SMOC), foramsulfuron (FORAM) and thiencarbazone-methyl (TCM) is still unclear. The objective here was to conduct a laboratory experiment to evaluate the impact of milled wheat straw (WS) simulating its individual use as mulch or applied as an organic amendment to two agricultural soils: unamended and WS-amended soils on the degradation kinetics of the herbicides SMOC, FORAM and TCM, and on the formation of their major metabolites at two incubation temperatures (14 °C and 24 °C). The degradation rate of SMOC on WS was 6.

Mulching vs. organic soil amendment: Effects on adsorption-desorption of herbicides.

Mulching and organic soil amendment are two agricultural practices that are being increasingly used to preserve soil from degradation, although they may modify the fate of herbicides when applied in soils subjected to these practices. This study has set out to compare the impact of both agricultural practices on the adsorption-desorption behaviour of the herbicides S-metolachlor (SMOC), foramsulfuron (FORAM), and thiencarbazone-methyl (TCM) involving winter wheat mulch residues at different stages of decomposition and particle size, and unamended soils or those amended with mulch. The Freundlich K adsorption constants of the three herbicides by mulches, and unamended and amended soils ranged between 1.