Study On Groudwater Hydro-Ecological Security Evaluation Information System In Arid Areas

Groundwater is an important part of water resources, is the most abundant and widely distributed freshwater resources on the earth. Groundwater has significant meaning for people’s living, social and economic development, it is an important factor to constitute and affect the ecological environment. Surface water resource in arid areas has limited quantity, people’s social producting and daily life mainly use the groundwater resource, the land ecological system mainly depends on the groundwater, and all these characteristics show that the groundwater has an irreplaceable position. Therefore, solving the groundwater hydro-ecological problems has far-reaching significance for the implementation of sustainable utilization of the water resource and protection of ecological environment in arid areas.Hydro-ecological system study is the concern hot topic in21st century. As an important direction in the concept of sustainable development, maintain and guarantee hydro-ecological system and water security become the foremost issue in rational utilization of water resources and the protection of ecological environment for regional developing. This study focuses on subject of groundwater hydro-ecological system, in view of groundwater and hydro-ecological security problems of the typical oasis in arid area of northwest China Shihezi reclamation area, discusses the theory of groundwater hydro-ecological security, constructes the indicator system for assessment of hydro-ecological security, researches the evaluation models, evaluates the groundwater hydro-ecological condition of Shihezi reclamation area in Xinjiang province of China, and based on this, utilizes the information technology into the hydro-ecological research fields to promote the theory research to practice. The main research content as follows:(1) Basic theory research, groudwater hydro-ecological system is a kind of open system far from the balance state, is a combination of groundwater’s physical properties, chemical composition, storage space and the states formed by natural geological process and human engineering-economic activities. Groundwater hydro-ecological security defined as:state characteristics of groundwater hydro-ecological system and the stability and sustainable ability of maintaining its own resources, ecology and environment function. Discusses the connotation of groundwater hydro-ecological security evaluation and the working process, and based on which, presentes the connotation of groundwater hydro-ecological security evaluation information system.(2) Based ont the system theoretical method, designs the overall struct of GIS-based groundwater hydro-ecological security evaluation information system. This system is a spatial information system that based on gis basic platform, can undertake spatial data storage and presentation, anylyze the groundwater information data in spatial and temporal scale, including database management and maintenance subsystem, data processing subsystem, groundwater hydro-ecological security evaluation indicator screening subsystem, groundwater hydro-ecological security evaluation subsystem, groundwater hydro-ecological information service subsystem, make whole groundwater hydro-ecological security evaluation work systematization, integration and automation.(3) Research of groundwater hydro-ecological security evaluation indicator system establishment and indicator selection. Groundwater hydro-ecological system is affected by natural factors and human factors, summarizing, groundwater hydro-ecological security evaluation indicators are groundwater resource recharge modulus, groundwater resources exploitable modulus, groundwater table, ground water levels drawdown rate, soil salinization rate, groundwater salinity, groundwater exploitation modulus, water-consumption per10000yuans GDP etc.40factors such as optional indicators.On the basis of groundwater hydro-ecological security evaluation indicator system, indicators’security levels are defined and the quantitative definition and description are carried out. Further, designs and develop the evaluation indicator screening subsystem that integrated the principal component analysis, analytic hierarchy process etc. several common indicator selection algorithm.(4) With Shihezi agricultural reclamation area in arid area as an example, verifies the evaluation models’reliability for groundwater hydro-ecological security evaluation, and tests the work effectiveness and efficiency of hydro-ecological security evaluation information system that developed based on ArcEngine.The evaluation results show that, the groundwater hydro-ecological system conditions of five irrigated area in Shihezi agricultural reclamation area:Shihezi irrigated area, Jin’an irrigated area, Xiayedi irrigated area, Mosuowan irrigated area, and Manas irrigated area, are as follows:Shihezi irrigated area’s groundwater hydro-ecological system security level is safe, the system resource supply function, ecological maintain function and groundwater quality is good, chemical compositions are stable, effectively support the water requirement of Shihezi irrigated area’s industrial and agricultural producting as well as living. Jin’an irrigated area groundwater hydro-ecological system security level is basic safe. Xiayedi irrigated area mainly exploites the confined water, groundwater drawdown rate is high, water table is deep, north edge area land desertification relatively serious, groundwater hydro-ecological system belong to the basic safe status. Mosuowan irrigated area exploites groundwater to satisfy producting, living and ecological water requirements; neighbor with desert, precipitation exiguous, groundwater recharge pattern is single, regional hydro-ecological environment is bad, and groundwater renewable ability is weak, groundwater resource demand and supply exist contradictions. The regional local area in groundwater drawdown rate is high, some area’s salinity reach20g/L, the regional groundwater hydro-ecological system is in crisis states. Manas irrigated area groundwater hydro-ecological system belongs to very safe state.According to the groundwater hydro-ecological condition of Shihezi agricultural reclamation area, propose to control mountain environment condition, emphasize water source conservation and soil desalting treatment, simultaneously control quantity of cultivated land, promote agricultural water saving measures and conduct water resources planning, rational use of water resources and establish a complete groundwater hydro-ecological dynamic monitoring system.