| The basic characteristics of pesticide chemical pollutants, the main factors which influence the transport of pesticide chemical pollutants in soil and the transport mechanism of water and pesticide chemical pollutants in unsaturated soil are researched based on the researches of predecessors. Several dynamic models, which describe the transport of pesticide chemical pollutants in soil, are established by considering several dynamic actions. The parametric inversion is studied, and the parameters of concentration field model are inversed by using least-squares techniques and Newton iterative method. The finite difference scheme — ADI method is used to solve the seepage field model. For the two-region/two-site model, the quasi-ADI method, which is used to treat mixed partial derivative, is given. The computing program is composed, and it is used to calculate an example and analyze the sensitivity of parameters, and the transport regulars of pesticide contaminant in unsaturated soil are explored and discussed by using the program. At last, some advises about preventing contaminants are given. The research in this paper has theoretical and practical significance to predict the transport and transformation law of pesticide chemical pollutants, evaluate environmental quality, use pesticide properly and control environmental pollution.
|
PDF Full Text Request