土壤中不动水体对溶质运移影响模拟研究  

Experimental and Model Simulation of Influence of Immobile Water on Solute Transportation in Soil

作　　者：李勇[1] 王超[1] 汤红亮[1] 

机构地区：[1]河海大学环境科学与工程学院,江苏南京210098

出　　处：《农业环境科学学报》2005年第1期104-108,共5页Journal of Agro-Environment Science

基　　金：国家重点基础研究发展计划(973计划)资助项目(2002CB412303);江苏省研究生培养创新工程资助项目

摘　　要：通过室内细砂土柱实验研究了保守性物质在土壤中运移特性,并采用考虑不动水体和忽略不动水体两种数学模型进行模拟,研究发现,考虑不可动水体和忽略不可动水体的数学模拟结果与实测值比较,平均误差分别为5%～10%和9%～15%,表明考虑不动水体的土壤溶质运移数学模型,能更准确地反映溶质的对流弥散运移特征。We employed a silver sand soil column experiment, and studied the transport characteristics of conservative solutes (Cl-and Br-) in this test.Firstly, KBr solute was added instantaneously into the soil column at two periods, namely, 5 min and 15 min, respectively. Secondly NaCl and KBr solutes were mixed continuously into the soil column (240 min). Based on the instantaneous experiment, only about 91.5%of total input perforated the soil column sections at z=30 cm and z=80 cm, while the rest part of 8.5%resided in immobile water. The results showed that transportation of the solutes in both mobile and immobile water in soil and the immobile water of soil may temporarily reserve or release solutes, influencing the transport process of solutes in soil. Simultaneity, calculated results from mathematical models under both considering and ignoring immobile water were compared with observed data from soil column according to thecontinuous experiment. We have found that breakthrough curves (BTCs) of Cl-and Br-were coincident. The mean difference of comparison of observed data (Cl-and Br-at z=30 cm, 80 cm and 150 cm) with calculated data under considering and ignoring immobile water, with mean correlation coefficients of 0.981 2 and 0.965 3 (n=45), were in a range of 5～10%and 9～15%respectively. Consequently, the mathematical model considering immobile water, which reflects compatibly the solute transport process in the soil, overmatches ignoring immobile water in some studies.

关 键 词：土壤 溶质运移 不可动水体 

分 类 号：X830.3[环境科学与工程—环境工程]