Effects of Aging on Bioreactive Chemical Retention,Transformation,and Transport in Soil
The fate of a bit-reactive organic chemical, such as a pesticide, in the soil environment is governed by the retention, transformation, and transport processes, and the interaction of these processes. Retention is the consequence of interaction between the chemical and the soil particle surface or soil components thereon. The retention processes, frequently described as adsorption or simply sorption, may be reversible or irreversible. Understanding the sorption process for a pesticide is important as it can retard or prevent pesticide movement, and affect availability of the pesticide for plant or microbial uptake or for biotic or abiotic transformation. While sorption is affected by the physical and chemical properties of both the pesticide and the soil particle resulting in a variety of retention mechanisms, increased contact time (i.e. aging) may also result in the formation of a stronger bond or a change in the binding mechanism between pesticide and soil, matrix deformation, diffusion of pesticide into remote sorption/binding sites (i.e. microsites in soil micropores), physical entrapment or sequestration of the pesticide in soil organic matter or clays, or a combination of these processes, all of which may affect the retention or sorption/desorption of the chemical in soil and in turn affect the processes of its transformation and transport (Cheng, 1990; Cheng et al., 1994; Cheng and Koskinen, 2002).
Sorption Desorption Aged residues Bioavailability
Hwei Hsien Cheng William C.Koskinen
Department of Soil,Water,& Climate,University of Minnesota,St.Paul MN 55108 USA USDA-Agricultural Research Service,St.Paul,MN 55108 USA
国际会议
杭州
英文
184-186
2009-10-10（万方平台首次上网日期，不代表论文的发表时间）