CAJ | 학술논문

农药在土壤中的吸附和淋溶特性是评价农药在土壤中迁移的重要指标.采用振荡平衡法、土壤薄层层析法和土柱淋溶法,研究甲羧除草醚在3种不同类型土壤中的吸附和移动特性及其影响因素.结果表明,甲羧除草醚在江西红壤、太湖水稻土与东北黑土中的吸附较好地符合Freundlich方程,Kd值分别为20.2、146.1和240.1,Kd值大小次序依次为:江西红壤<太湖水稻土<东北黑土.影响甲羧除草醚土壤吸附性的主要因素为土壤有机质.通过对土壤吸附自由能计算,3种土壤的DG值分别为–18.86、–23.17和–23.66 kJ·mol-1,说明该吸附为自发过程;同时,DG绝对值小于40 kJ·mol-1,说明该吸附为物理吸附.薄层层析试验和土柱试验表明甲羧除草醚在3种土壤中不易移动,淋溶试验的结论为难淋溶.影响甲羧除草醚在土壤中吸附性和移动性的主要因素为土壤有机质含量和在水中的溶解度.
농약재토양중적흡부화림용특성시평개농약재토양중천이적중요지표.채용진탕평형법、토양박층층석법화토주림용법,연구갑최제초미재3충불동류형토양중적흡부화이동특성급기영향인소.결과표명,갑최제초미재강서홍양、태호수도토여동북흑토중적흡부교호지부합Freundlich방정,Kd치분별위20.2、146.1화240.1,Kd치대소차서의차위:강서홍양<태호수도토<동북흑토.영향갑최제초미토양흡부성적주요인소위토양유궤질.통과대토양흡부자유능계산,3충토양적DG치분별위–18.86、–23.17화–23.66 kJ·mol-1,설명해흡부위자발과정;동시,DG절대치소우40 kJ·mol-1,설명해흡부위물리흡부.박층층석시험화토주시험표명갑최제초미재3충토양중불역이동,림용시험적결론위난림용.영향갑최제초미재토양중흡부성화이동성적주요인소위토양유궤질함량화재수중적용해도.
Abstact: The adsorption and leaching of pesticides in soils are important evaluation index which can be used to describe the migration characteristics in soil. In this study, the adsorption and leaching of bifenox in different soils in China were conducted by oscillation equilibrium experiment, soil TLC and column leaching. The results showed that bifenox in the above soils were better fitted by the empirical Freundich adsorption isotherm. The adsorption constant (Kd) in Jiangxi red soil, Taihu paddy soil, Northeast China black soil were 20.2、146.1 and 240.1. The extent of bifenox adsorbed by soils followed:Jiangxi red soil<Taihu paddy soil<Northeast China black soil. The soil organic matter content was the dominant factor which affected the adsorption of bifenox in soils. Based on the calculation of free energy of soil adsorption, charges of free energy (DG)in Jiangxi red soil, Taihu paddy soil, Northeast China black soil were–18.86、–23.17 and–23.66 kJ·mol-1, the bifenox adsorption by soils belonged to spontaneous process. The bifenox adsorption by soils belonged to physical adsorption with charges of free energy less than 40 kJ·mol-1. In all the kinds of experimental soil, bifenox showed comparatively low mobility and leaching degree. The soil organic matter content and solubility of bifenox were considered as the major factors which affected the adsorption and leaching of bifenox in soils.