南水北调中线工程水源林生态系统对水质的影响——以秦岭南坡中山地带火地塘林区为例  

Effect of the forest ecosystem on water quality in the water supply catchment for the middle line of South-to-North Water Transfer Project: A case study of the Huoditang forest,part of the medium altitude,southern slope of the Qinling mountain range

作　　者：张胜利[1] 李靖[1] 韩创举[1] 王德连[1] 

机构地区：[1]西北农林科技大学,陕西杨凌712100

出　　处：《水科学进展》2006年第4期559-565,共7页Advances in Water Science

基　　金：西北农林科技大学校长基金资助项目(08080215);国家林业局重点科研资助项目(2001-04)

摘　　要：通过对秦岭南坡中山地带火地塘林区大气降水与支沟溪流水和流域出口径流水质的比较分析，以及溪流水和流域出口径流水质与水量的相关分析，发现7—10月份大气降水呈微酸性，经过森林生态系统的调节，径流pH值升高，且不随流量变化而发生变化；森林生态系统对随降水输入的NO3^-、NH4^＋、PO4^3-有很好的净化作用，这种作用对于降低南水北调中线工程取水地丹江口水库水质富营养化的威胁非常有益，对重金属元素Cd、Pb、Mn有固定作用；对K、Na、Ca、Mg、Fe有增加作用，尤其对Ca、Mg含量增幅较大，但这种作用不会对水质产生不良影响，对Fe的调升有利于水质改善；森林生态系统在调减Zn含量方面作用显著；林区径流水质与水量之间并无较大关系，水质不随水量变化而发生较大变化，森林生态系统对水质有很好的稳定作用。The objective of this research is to determine the effect of the forest ecosystem on water quality in the Huoditang Forest, part of the water supply catchment for the South-to-North Water Transfer Project. The effect of the forest on water quality was determined by measuring the water quality of rainfall and stream water collected from tributaries within the watershed and at the watershed outlet. The water flow rate in the streams was also taken into account. From July to October, rainfall was slightly acidic. The pH of the stream water was higher than that of the rainfall and was not affected by flow rate. The concen- tration of NO3^- , NH4^＋ , and PO4^3- in the stream water were lower than in the rainwater, indicating that the forest ecosystem was effective for reducing the level of these nutrients in water. This should reduce the probability of water eutrophication in the Danjiangkou Reservoir, the main water storage area for the South-to-North Project. The forest ecosystem also fixed the heavy metals Cd, Pb and Mn. This is helpful for improving water quality. The concentration of K, Na, Ca, Mg and Fe in the water ship between water quality and flow rate. Generally, there is no large change in water quality as flow rate varied. The results from this study show that the water quality is stabilized as it passes through the forest ecosystem.

关 键 词：南水北调 秦岭 森林生态系统 水质 影响 

分 类 号：X171.1[环境科学与工程—环境科学]