摘要
黄河源区地处青藏高原中南部,海拔高度在4100m以上,属中纬度高山多年冻土带,该冻土带内形成了一种特殊的冻结水环境。多年冻土通过季节融化带与大气系统、植被系统、地表水系统进行水、热交换,冻结层上水则是交换中的重要纽带。冻结层上水分布在冻土表层,是冻土区主要的潜水含水层之一,其空间分布直接控制着包气带含水量的变化和地表植被类型分带。2000～2001年,作者两次对黄河源区冻结层上水及其地质环境进行了专题研究,结果表明,水文地质结构、地表水位的变化以及过度放牧和开采沙金等人为作用均会对冻结层上水的空间分布产生影响,这些作用不仅影响着冻土类型的转化,而且还会由此引发一系列的生态问题,使原本十分脆弱的生态环境出现恶化。
The headwater region of the Yellow River is located in centralsouthern QinghaiTibet Plateau with an elevation of 4100m or more. The area belongs to a perennial permafrost zone in an alpine belt with middle latitude. In the permafrost zone occurs a kind of special permafrost water. In the environment of permafrost water, exchange of water and heat between the permafrost and the atmospheric system, vegetationsystem and surface water system occurs through the seasonal thawing layer. For this reason, the suprapermafrost water acts as an important link between them. The suprapermafrost water occurs in nearsurface permafrost, and is one of the major phreatic aquifers. The horizontal and vertical distribution of suprapermafros water directly controls the change in water contents in the unsaturated zone and the zonality of surface vegetation. Two specialty investigations were made of the suprapermafros water and its impacts on the geological environment in the headwater region of the Yellow River in the period 2000～2001. Field data indicate that changes in hydrogeological structure, and water table, as well as such human activities as overgrazing and sandgold mining have an important influence on the spatial distribution of the suprapermafrost water. Not only does the transferring of the type of frozensoil be affected, but also a series of ecological problems can be introduced. As a result, the original fragile ecoenvironment well be degradatel.
出处
《水文地质工程地质》
CAS
CSCD
2003年第6期6-10,共5页
Hydrogeology & Engineering Geology
基金
国土资源部2000年地质调查项目(20012300002)资助
关键词
黄河源区
地质环境
冻结层上水
青藏高原
生态环境
suprapermafros water
ecological environment
Qinghai-Tibet Plateau
headwater region of the Yellow River
