Application Of Connection Number In Drought Vulnerability Analysis And Evaluation

Drought disaster has always been a natural disaster with great harm.Due to its uncertainty and complexity,it has always been a difficult problem to control and prevent.With the dramatic change of global climate in recent years,the harm caused by drought disaster to human society is also increasing.In this paper,a macro evaluation model of drought vulnerability based on connection cloud is established,and the level change of regional agricultural drought disaster vulnerability is comprehensively evaluated.On this basis,the drought disaster vulnerability index is identified by the constructed five-elements effect total partial connection coefficient.The main works and the corresponding conclusions are as follows:(1)In order to manage the agricultural drought disaster scientifically and effectively,reduce or avoid the agricultural losses caused by drought disaster,a regional agricultural drought disaster vulnerability evaluation model based on connection cloud is built to evaluate the agricultural drought disaster vulnerability in Bengbu City.The possibility that an evaluation index belongs to each level is expressed by the degree of certainty,which overcomes the defect of traditional cloud model and makes the evaluation more reasonable.After analysis and calculation,the following evaluation results are obtained: the vulnerability levels of agricultural drought disaster in Bengbu City from 2001 to 2003 are level IV,and those from 2004 to 2012 are all level III.The evaluation results are basically consistent with the results of fuzzy comprehensive evaluation,cloud similarity,and the coupling of connection number and grey correlation methods.It indicates that it is reasonable to use connection cloud to evaluate the vulnerability of agricultural drought disaster,and it is more scientific than the evaluation results obtained by traditional cloud model method.(2)On the basis of the existing research on three-elements effect total partial connection coefficient,the calculation formula of five-elements effect total partial connection coefficient is put forward.At the same time,with the help of trend curve area for partial connection coefficient,the connotation of effect total partial connection coefficient is further explained.Meanwhile,the application range of effect total partial connection coefficient is expanded.The effectiveness of five-elements effect total partial connection coefficient is verified by the example of water resources carrying capacity in Sichuan Province.The results show that there is a high degree of consistency between the five-elements effect total partial connection coefficient andthe five-elements fourth order total partial connection coefficient for the dynamic analysis and evaluation of water resources carrying capacity in Sichuan Province.Moreover,the five-elements effect total partial connection coefficient can reflect the development trend of evaluation object more obviously,and the calculation process is simpler Therefore,the evaluation results are more reasonable and more in line with the physical meaning of partial connection coefficient.The diagnosis results of five-elements effect total partial connection coefficient to agricultural drought disaster vulnerability index is consistent with the actual situation.In addition,the diagnosed four indexes have a greater fluctuation with the change of year,and the four indexes have a greater impact on the comprehensive evaluation results of drought disaster vulnerability.To sum up,this paper constructs an analysis method with the integration of evaluation and diagnosis,which provides an effective method for the analysis and evaluation of agricultural drought disaster,establishes a scientific basis for the management of agricultural drought disaster vulnerability,and improves the research method system of drought disaster vulnerability.