Assessment Methods for Hazard Bearing Vulnerability of Water and Land Resources to Floods and Droughts
水土资源对旱涝灾害的承险脆弱性研究方法探讨

Hazard bearing vulnerability is of crucial importance in assessing hazard risk. It seems that natural resources research primarily focuses on resources exploration and utilization, with less studies being performed on the relationship between natural resources and natural disasters; the latter has a significant influence on the former. Assessment for hazard bearing vulnerability of natural resources has been rarely carried out. Water and land resources constitute the foundation of agricultural production, which is dominated in economic areas in China. Thus assessment of their hazard bearing vulnerability is of more significance. This paper aims to analyze the hazard bearing vulnerability of water and land resources to floods and droughts. The authors established key indicators for assessing the hazard bearing vulnerability of water and land resources to floods and droughts based on the Prevalent Vulnerability Index (PVI). The index consists of 3 sub-categories, i.e., physical exposure, inherent vulnerability and regional resilience. The indicators of physical exposure include the area and length of affected resources and intensity and frequency of the hazard events. Inherent vulnerability of land resources can be evaluated by land use types. Meanwhile, water quality is used to measure the inherent vulnerability of water resources. Regional resilience is generally grouped into two categories, which are basic resilience capacity and specific resilience capacity. Basic reliance capacity indicates the whole hazard relief capacity of a region which can be evaluated by the Gross Domestic Product (GDP) and GDP per capita. Specific resilience capacity can be measured by investment to reduce hazard effects. As for droughts, regional specific resilience capacity can be measured by reservoir capacity and numbers of power-operated well and water shortage rate for paddy land and irrigation loss rate for dry land. As to hazard events of floods, levee length and reservoir capacity can be used to assess the specific resilience capacity of a region. By assessing hazard bearing vulnerability of land and water resources to floods and droughts, policies on hazard effect relief can be made in a more reasonable way and investment of hazard effect relief would be more effectively used.