Aminocyclopyrachlor sorption-desorption and leaching from three Brazilian soils

作者：Francisco Jeane G; Mendes Kassio F^*; Pimpinato Rodrigo F; Tornisielo Valdemar L; Guimaraes Ana C D

来源：Journal of Environmental Science and Health - Part B: Pesticides, Food Contaminants, and Agricultural Wastes , 2017, 52(7): 470-475.

DOI：10.1080/03601234.2017.1301758

• Herbicide transport
• pyrimidine carboxylic acid
• retention
• tropical soils

This study aimed to evaluate the sorption-desorption and leaching of aminocyclopyrachlor from three Brazilian soils. The sorption-desorption of C-14-aminocyclopyrachlor was evaluated using the batch method and leaching was assessed in glass columns. The Freundlich model showed an adequate fit for the sorption-desorption of aminocyclopyrachlor. The Freundlich sorption coefficient [K-f (sorption)] ranged from 0.37 to 1.34 mu mol ((1-1/n)) L-1/n kg(-1) and showed a significant positive correlation with the clay content of the soil, while the K-f (desorption) ranged from 3.62 to 5.36 mu mol ((1-1/n)) L-1/n kg(-1). The K-f (desorption) values were higher than their respective K-f (sorption), indicating that aminocyclopyrachlor sorption is reversible, and the fate of this herbicide in the environment can be affected by leaching. Aminocyclopyrachlor was detected at all depths (0-30cm) in all the studied soils, where leaching was influenced by soil texture. The total herbicide leaching from the sandy clay and clay soils was <0.06%, whereas, approximate to 3% leached from the loamy sand soil. The results suggest that aminocyclopyrachlor has a high potential of leaching, based on its low sorption and high desorption capacities. Therefore, this herbicide can easily contaminate underground water resources.

• 出版日期2017