摘要
在提出关于“地下水防污安全埋深”定义的基础上,以陕西交口抽渭灌区为例,将灌区灌溉水、土壤层和地下水视为水-土-水系统进行了整体研究,并把理论研究成果与灌区的实际状况相结合,从铬和砷在土壤中迁移转化及其净化的机理出发,通过选择耕作层下渗水量的水流运动模型、铬和砷在耕作层及包气带土壤层迁移转化的模型,根据灌区的实际勘察和野外试验结果确定了不同模型的相关参数,分别以灌溉水的实测浓度及拟设的其他不同浓度进行了耦合计算。结果表明,在黄土灌区,当灌溉水中铬和砷浓度不大于10.0m g·L-1的情况下,防止地下水铬和砷污染的安全埋深分别为不小于5.0m和1.5m,为灌区制定防止水土资源污染的有效措施提供了依据。
Jiaokou irrigation area in Shaanxi Province utilizes Wei River as its water source for farming. In recent years, as extension of cities and industries in the region, Wei River has been polluted seriously. As the water source for irrigation, Wei River has an important influence on ecological environment andthe quality of groundwater in the area. In order to lessen harm of polluting water irrigation to soil and groundwater, it is important to put forward efficiency measures to prevent soil and groundwater from pollution. As to the definition of Safely Buried Depth of protecting groundwater from pollution, it is the givenburied depth from groundwater table to surface. The soil layer in this depth can ensure that harmful elements are purified when polluted surface water seeps into it, and groundwater is not polluted. Determining the Safely Buried Depth of protecting groundwater from polluting is a critical problem that needs considering comprehensive factors. Taking with Jiaokou irrigation area in Shaanxi as example, the integral researches are carried out by regarding irrigation water, soil and groundwater as surface water-soil-groundwater system. The theoretical research results combine with present conditions of irrigation area. Proceeding from mechanism that Cr and As migration, transformation and purification in the soil, the coupling calculated results are concluded by choosing cultivated horizonmodel of water flow movement and aeration zone model of Cr and As migration andtransformation in cultivated and aeration horizons, determining the parameters of different models according to survey and field experiment results, and using actual analyzed and given concentrations, respectively. The results indicated that in loess area, when concentrations of Cr and As are less than 10.0 mg·L-1in sewage infiltration fluid, the purification depths of Cr is 5.0 m, and that of As is 1.5m in loessial soil. For irrigation area, if the concentration of Cr for irrigation water is 1.0 mg·L-1, after irrigating continuously 20 d,
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2005年第2期333-336,共4页
Journal of Agro-Environment Science
基金
国家科技攻关计划项目资助(2002B A901A43)
长安大学科技发展基金项目资助(04Z08)
关键词
陕西交口灌区
地下水
铬
砷
安全埋深
Jiaokou irrigation area in Shaanxi
groundwater
Cr and As
safely buried depth
