Meteorological Disaster Risk Assessment And Zonation Of Winter Wheat In Shaanxi Province

Shaanxi Province is located in the excessive belt between northwest continental climate and southeast coast monsoon climate, it belongs to the fragile ecological environment area. Because of the special geographical location and features, agricultural production is often affected by a variety of meteorological disasters, crop yields suffered serious losses. Applied natural disaster risk assessment theory and techniques to agricultural fields, combine with the agro-meteorological disasters’s formation mechanism to evaluate agro-meteorological disasters’ hazard ris、environmental sensitivity of breed disaster、vulnerability of carrier and disaster prevention and mitigation capabilities is an important direction of agrometeorological disasters risk assessments. So far, most of the researches are considered single disaster as research subjects at home and abroad, for a variety of meteorological disaster risk research is still rare, and can not reflect the actual weather condition general risks for agricultural production.In view of this, this paper uses relevant information of Shaanxi province to establish a meteorological disaster risk assessment model and study the majoy agro-meteorological disaster risk assessment of winter wheat based on the agro-meteorological disasters’s formation mechanism. The main conclusions are as follows:(1) Identification of winter wheat disastersIdentified the agricultural meteorological disasters during winter wheat’s whole growth period, determined the main disaster of winter wheat in Shanxi province are drought, frost, hot wind and so on.(2) The construction of indicesDeparture from the definition of meteorological disasters risk and factors, constructed each single-hazard disaster’s risk index. In order to reflect the effect of combined effects of disasters, the paper used gray correlation analysis to analysis single-hazard disaster index and cut rate. results show that the most harmful disaser of wheat drought disaster in Shaanxi province is drought, followed by winter frost, followed by late frosts, the Minimal harm disaster is dry-hot wind. Calculate various types of disasters’ weights through correlation, then sum weighted to get the comprehensive disaster risk index of winter wheat’s meteorological disasters in Shanxin province. After the turn, build expression indexes of disaster-environmental sensitivity, carrier’s vulnerability, disaster prevention and mitigation capabilities.(3) Formation mechanism based on the theoretical risk of natural disasters and agricultural meteorological disaster risks, including the risk to establish risk assessment model, sensitivity, vulnerability and disaster prevention and mitigation four aspects. Using AHP, got the weight coefficients of these four factors were0.4214,0.2818,0.2141,0.0827and calculated the disaster risk index of winter wheat in Shaanxi Province, and then get Shaanxi Provincial Meteorological Disaster Risk Zoning classification method through natural breakpoint.(4) Results of the integrated meteorological disaster risk assessment and regionalizationWinter wheat’s high-risk areas in Shaanxi are in Yulin, Weinan and Xi’an; higher risk areas are mainly located in Xianyang and the fringe of Yan’an’s northern and eastern part; South of Yan’an, Fengxiang and small parts of Hanzhong, Baoji is moderate-risk areas; Lower-risk areas are mainly located in most part of Baoji and Hanzhong, the central of ankang and the southeast of shangluo; Several cities in Southern Shanxi such as Foping, Shiquan, Shangxian,and Zhenan are low-risk areas.