Influence of organic matter and pH on bentazone sorption in soils.
Bentazone (3-isopropyl-1H-2,1,3-benzonthiadiazain-(4)3H-one 2,2-dioxide) is a postemergence herbicide which is used extensively worldwide, especially in China. The sorption of bentazone in various types of soils and extracted humic acids was investigated using a batch equilibration technique. Significant linearity was observed in sorption isotherms in five different types of soil, with distribution coefficients (K(d)) that varied between 0.140 and 0.321 mL g(-1). The distribution coefficient was determined to be a function of organic matter and pH in the soil. A model based on distribution coefficients was developed to predict bentazone sorption in soils. The organic matter-normalized partition coefficients for the neutral and anionic forms of bentazone were 370.3 and 2.40 mL g(-1), respectively. Hence, more attention should be given to the potential leaching problem when bentazone is applied in soils containing low organic matter and high pH.
Li
Kebin
K
Institute of Environmental Science, Zhejiang University, P.O. Box 1707, Hangzhou 310027, People's Republic of China.
Liu
Weiping
W
Xu
Dongmei
D
Lee
Sangjin
S
D000327:Adsorption; D001581:Benzothiadiazines / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D006540:Herbicides / Q000737:chemistry*; D006812:Humic Substances / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D012987:Soil
D001581:Benzothiadiazines; D006540:Herbicides; D006812:Humic Substances; D012987:Soil; C002003:bentazone