Concept and Quantitative Assessment of Vulnerability of Surface Water Resource
地表水资源的脆弱性及其评价初探

Vulnerability assessment of water resource system is very important for regional water management,water allocation and economic development.However, little attention has been paid to the surface water resource system in the South China,which is the primary water resource in this area.In this research,the Hengyang Basin is selected as the representative area of the South China based on some considerations such as data available,geographic characteristics,administrative boundaries and human activities.First,a concept of vulnerability of surface water system expressing the characteristics of surface water resource system in the South China is presented based on the resource and environment theory.The connotation and the contributing factors of the surface water vulnerability are analyzed subsequently.The vulnerability of surface water includes water quality and water quantity both of which contain natural vulnerability,artificial vulnerability,and burdening vulnerability.An assessment index system is established and applied to calculate the vulnerability degree,which is an indicator of water resource vulnerability during the exploitation and the utilization of regional water.Twelve assessment factors are selected based on the conditions of supply capacity,demand stress,and utilization efficiency of water subjected to the regional physical,economic,and water conservancy settings.These factors are integrated into the complex index model,which is capable and effective for the vulnerability assessment.And the vulnerability degrees of seven counties in the Hengyang Basin are calculated.The assessment results demonstrate the vulnerability of surface water in the Hengyang Basin is great and the regional distribution of the center and the north basin is greater than that of the south basin.Moreover,the assessment results are consistent with the practice,which indicates that the index system and the assessment method are credible.Therefore,enhancing the vegetation covering,strengthening the irrigation facilities,improving the water utilization efficiency,and adjusting the agricultural layout are important water management measures in the South China.