Agricultural Drought Disaster Risk Evaluation Of Henan

Under the trend of global warming,the disaster brought by drought disaster is becoming more and more serious,drought disaster has become one of the most common natural disasters in the world.As a large grain Province in China,the effection of agricultural drought disaster which already direct lead to the agricultural production restricts has become a serious problem in Henan.Systematically evaluating the agricultural drought disaster is very significance to improve the efficiency of agriculture production,grain safety and socioeconomic sustainable development in Henan Province.The agricultural drought disaster is a very complex system which is comprehensive influenced by nature,society and other aspects,so it need to be fully considered.Drought disaster is influenced by many uncertain factors such as the hazard risk,disaster environment vulnerability,vulnerability of hazard bearing body and disaster prevention and mitigation capacity,therefore,whether the risk factors selected can accurately reflect the drought and quantitatively describe the drought degree and how to identify the uncertain factors in drought risk is the current problem which needs to solve in agricultural drought risk.This paper study on disaster-causing mechanism of agricultural drought disaster,based on the systematic analysis of the impact factor of agricultural drought in Henan Province,start with four factors include exposure of the risk factor,hazard-affected body,environmental vulnerability and drought disaster reduction ability to analysis the reasons of agricultural drought risk.Based on the theory of disaster science this paper use analytic hierarchy process(AHP),weighted comprehensive evaluation method and natural disaster risk index to build agricultural drought disaster risk assessment system,then describe the agriculture drought risk zoning map.According to the weather,agriculture,social and economic data and using the optimal segmentation method and fuzzy information distribution method to evaluation drought disaster risk probability of the typical city in Henan.The main conclusions are as follows:(1)Analysing the drought characteristics from the temporal and spatial distribution two aspects of Henan province in the past 60 years;from the social and natural factors which influence agricultural drought disaster to analyse the agricultural drought disaster mechanism.(2)Starting from the impact of agricultural drought disaster risk of the four elements of the hazard risk,disaster environment vulnerability,vulnerability of hazard bearing body anddisaster prevention and mitigation capacity ability,establishing the agricultural drought disaster risk model by selecting appropriate indicators to quantify the risk value,and drawing the agricultural drought risk map.The trend of agricultural drought disaster risk is descending from north to south in Henan province,longitude direction through the middle east to the west is gradually decline,the south of Henan is in the low risk area.The central part of Henan Province such as Pingdingshan,northern area such as Jiyuan and Hebi are in the high risk area;the central part such as Zhengzhou,Kaifeng,Xuchang and other regions are in the high risk area;drought risk is small in the middle of Henan Province such as Luoyang,Zhoukou southern Nanyang,Xinyang and other places are in the low risk area.(3)According to the agricultural drought index,using the optimal partition method to determine the risk grade standards.Choosing Xinxiang,Sanmenxia,Nanyang,Zhengzhou,Shangqiu as the agricultural drought disaster probability assessment typical area,using fuzzy information distribution method to evaluate drought risk value in the typical area,and get the following conclusions: The probability of low and moderate risk is higher in Nanyang,but the probability of high risk and extremely high risk in Nanyang is low;Sanmenxia and Zhengzhou have the highest probability of occurrence of the medium risk,the minimun probability of occurrence of low risk;the occurrence of Shangqiu and Xinxiang in medium risk and high risk probability is larger.