Monosulfuron-ester is a new,low rate,sulfonylurea herbicide that is being promoted for annual broadleaf and gramineal weed control;however,there is a lack of published information on its behavior in soils.The adsorpti...Monosulfuron-ester is a new,low rate,sulfonylurea herbicide that is being promoted for annual broadleaf and gramineal weed control;however,there is a lack of published information on its behavior in soils.The adsorption and desorption of monosulfuronester by seven type soils were measured using a batch equilibrium technique.The results showed that the Freundlich equation fitted its adsorption and desorption well,and the Freundlich constant values （K f-ads ） ranged from 0.88 to 5.66.Adsorption isotherms were nonlinear with 1/n f-ads values 1.Soil pH,organic matter （OM）,and clay content were the main factors influencing its adsorption and desorption.Adsorption and desorption were negatively correlated with pH 4.0–8.0 while positively correlated with OM and clay content.The adsorption of monosulfuron-ester was mainly a physical process,because its free energy （？G） in seven soils was less than 40 kJ/mol.Monosulfuron-ester adsorption by three soils increased with increasing CaCl 2 concentration using CaCl 2 as a background electrolyte.Monosulfuron-ester desorption was hysteretic in all tested soils.展开更多
基金supported by the National Basic Research Program (973) of China (No.2009CB119200)the Chongqing Natural Science Foundation (CSTC) (No.2009BA1042)the Program for Changjiang Scholars and Innovative Research Team in University (No.IRT0976)
文摘Monosulfuron-ester is a new,low rate,sulfonylurea herbicide that is being promoted for annual broadleaf and gramineal weed control;however,there is a lack of published information on its behavior in soils.The adsorption and desorption of monosulfuronester by seven type soils were measured using a batch equilibrium technique.The results showed that the Freundlich equation fitted its adsorption and desorption well,and the Freundlich constant values （K f-ads ） ranged from 0.88 to 5.66.Adsorption isotherms were nonlinear with 1/n f-ads values 1.Soil pH,organic matter （OM）,and clay content were the main factors influencing its adsorption and desorption.Adsorption and desorption were negatively correlated with pH 4.0–8.0 while positively correlated with OM and clay content.The adsorption of monosulfuron-ester was mainly a physical process,because its free energy （？G） in seven soils was less than 40 kJ/mol.Monosulfuron-ester adsorption by three soils increased with increasing CaCl 2 concentration using CaCl 2 as a background electrolyte.Monosulfuron-ester desorption was hysteretic in all tested soils.
