Model establishment and zoning of wind-dust risk assessment tofeatured forestry and fruit industry in Xinjiang

Abstract: Natural disaster is a major adverse event resulting from natural processes of the earth, which consists from hazard bearing environment,hazard formative factors, hazard affected bodies, etc. Wind dust is one of the three major disasters of featured forestry and fruit industry in Xinjiang. The wind dust hazard caused great damage to the growth and yield of featured forestry and fruits in Xinjiang, due to its sudden happening,wide range of hazard affected areas and tremendous loss, meanwhile it has significant impact to the economy of local farmers and the whole region. To provide certain basis for the relevant production departments to defense and reduce the side effects of sandstorm disasters, this studyanalyzed the risk composition of wind dust disasters in three aspects, such as the risks of hazard-formative factor, the sensitivity of hazard affected environment and vulnerability of hazard bearing bodies, based on the theory of natural disaster system, combined with the characteristics of wind-dust disaster to the featured forestry and fruit industry in Xinjiang, and associated with the auxiliary data sets such as meteorological,basic geo-information and the agricultural and social economic data sets.In the disaster risk assessment zoning, reasonable empowerment for each hazard-formative factor would directly affect the reliability and formality of assessment results. This studyused the analytic hierarchy process (AHP) method and weighted comprehensive assessment method for properly selecting the item weighted indices for each factors in the disaster assessment model. According to the risk composition characteristics, this paper summarized the risk assessment indices in three aspects: the risk model of hazard-formative factors(intensity of wind-dust,wind days and frequency of wind-dust), sensitivity model of hazard affected environment(average wind speed, relative humidity,average temperature anddesertification area) and vulnerability model of hazard bearing bodies(GDPper area,cultivated land area, featured forest and fruit area, GDPper capita, development level of agricultural production),etc., and established the model of individual and integrated assessment indices, then discussed the practical principle of these indices to the assessment of wind-dust risks. Finally, on the basis of the comprehensive index model, the ArcGIS spatial analysis module tools was used todeterminethe assigned weights for each single evaluation index and proceed overlay analysis, to get the special distribution map of these three wind dust risk assessment indices, and overlaythe three indices to get the map of wind-dust risk assessment zone of featured forestry and fruit industry in Xinjiang. According to the comprehensive evaluation index(R) value, the system divided the Xinjiang region to fiveprevention and control area, and from the spatial distribution, southern forestry and fruit industry suffer higher wind dust risk than northern part. From the local distribution, the effects of wind dust hazards to forestry and fruit industry of southern margin of the Taklimakan desert and Hotan region are most significant.classified as the primary prevention and control area; For Toghrak desert, Bugiridesert, Kumtag desert, Gaxungobi district in Kashgar, Bazhou, Hami and Turpan regions,their forestry and fruit industry suffers relatively sever wind dust hazards, and classified as secondary prevention and control area; Other areas are classified as tertiary prevention and control area.