Risk Assessment Of Agricultural Drought In Dalian

With the economical development and global environmental change, the demand for water resources is increasing, so the threat of drought is growing. The agricultural system is complicated, and it responses to the drought strongly. Dlian is an important commodity grain base of Liaoning province. By the influence of the nature, social and other factors, the drought occurs frequently. Its agriculture receives the arid threat frequently. As the viewpoint of the system theory, the agricultural drought risk assessment includes the disaster mechanism analysis, the agricultural drought vulnerability appraisal and the loss assessment. Rested on this theory, this article carries on the assessment to Dalian's agricultural drought risk. The main research content and the achievement are as follows:(1)Using historical data, summarizes the characteristics of agricultural drought in Dalian, also analyzed the mechanism of agricultural drought disaster, from disaster environment, factors of causing and supporting body. The results show that the agricultural drought in Dalian is the result of the natural environment and role of social enviroment, Seasonal rainfall uneven distribution and water shortage are two important factors to agricultural drought.(2)Evaluate the drought vulnerability of Dalian .There are two parts. First, the agricultural drought vulnerability of the 7 agricultural areas in Dalian from 2000 to 2007 is evaluated. The annual change of the agricultural drought vulnerability in each area is less the same. Compared with other area, the frequency of the highest agricultural vulnerability is in Wafangdian, while the smallest in Lushunkou. Within the space, there are three grades in the agricultural vulnerability of all the areas. Pulandian, Wafangdian and Zhuanghe are intensity agricultural drought vulnerability area, Jinzhou and Chanhai are moderate agricultural drought vulnerability area, Ganjingzi and Lushunkou are slight agricultural drought vulnerability area. And use fuzzy comprehensive evaluation method to evaluate the agricultural vulnerability in the overall of Dalian. The result is that agricultural drought vulnerability is weak strongly, that is, the risk of drought in Dalian is greater.(3)Rating damage assessment of agricultural drought is an important part. Apply model for variable fuzzy assessment based on the theory of variable fuzzy to assess the drought degree in Dalian in 2002. The result shows that the drought is serious. thereby a comprehensive evaluation method with the consideration of multifactor is provided for drought.Last, propose the measures to combat drought, and a summary is given.