Research On The Groundwater Vulnerability Assessment Of The Lower Liao He River Plain

Content: With the development of economy recently, a series of environment problems appeared with the fast exploitation of water use scale, such as continuous descent of ground water level and serious pollution of water quality and so on. It is a very important thing currently that of strengthening groundwater programming, allocation reasonable, strengthening management and protecting it. Groundwater vulnerability reflects the relative potential possibility of groundwater system to be polluted, the research of groundwater vulnerability is the basis of groundwater protection. From this study to divide different vulnerability areas, estimate the relative potential possibility of groundwater system to be polluted and confirm the vulnerable area, it can caution people to protect water resource when they exploited.Geographic Information System (GIS) is a production with the development of computer technology and information systems. It has such functions as geography, drawing, data, analysis etc. With the system graph can be demonstrated and the database created, in addition analysis of geographical spatial data has been widely used. Since GIS is become more and more practical, which has the ability of synthetic analysis as well as spatial module construction, and to change and renew the database at any time, the evaluation process is facilitated, strong support is given to groundwater vulnerability, and the development of the research on groundwater vulnerability is promoted, so GIS has been widely applied in the evaluation and cartography of groundwater vulnerability.This paper is based on DRASTIC model, and takes GIS as tool, Taking the lower Liao he river plain area as the study area and based on the specific conditions of the study area, select appropriate parameters to form the vulnerability assessment factor system. On this basis, groundwater vulnerability assessment in the study area considered both intrinsic vulnerability and specific vulnerability. Intrinsic vulnerability considered two aspects: water quantity and water quality. In water quantity, taking aquifer thickness and crude recharge as parameters, and in water quality, selecting six indexes such as Soil organic material and so on as evaluate factors. Specific vulnerability evaluation selecting five indexes as evaluates factors, then convent the layer into Grid using vertical Mapper which is a model of MapInfo, after that made overlay analysis, then gained intrinsic vulnerability mapping and specific vulnerability mapping of the study area. Considered three scenes that put the intrinsic vulnerability mapping and special vulnerability mapping overlaid, at last gained three synthesis vulnerability mappings, through the research of groundwater vulnerability, the division of vulnerable extent of different section groundwater, the evaluation of potential pollution of groundwater and the fix of vulnerability scope of groundwater, people can apply practical measures when exploring and utilizing the groundwater in lower LiaoHe river plain to ensure the sustainable use of groundwater.