内蒙古草原干旱灾害综合风险评估

Assessment on the integrated drought disaster risk in Inner Mongolia grassland

区域气候变化对内蒙古草原影响凸显,干旱已经成为威胁内蒙古草原生态系统的首要自然灾害。基于自然灾害风险理论,利用内蒙古草原牧区54个牧业旗县的气象、土壤水分、植被、遥感、社会经济和地理信息数据,从旱灾致灾因子危险性、孕灾环境敏感性、承灾体易损性和防灾减灾能力4个方面选取影响干旱的8个关键性指标,采用层次分析法、加权综合评价法和专家打分法,确定风险指标权重,构建旱灾风险评估模型,借助GIS空间分析功能,对内蒙古草原旱灾风险进行综合评估。研究结果表明:综合旱灾风险指数空间分布呈"南高北低、东高西低"特点,具有较明显的地带性分布规律。内蒙古草原高、中、低旱灾风险等级面积分别占研究区总面积的21.3%、37.4%、41.3%。高风险区主要分布在呼伦贝尔市中部偏西地区、兴安盟西南部、通辽市大部、赤峰市中部、锡林郭勒盟南部、乌兰察布市中部、呼和浩特市北部、包头市中部偏南和鄂尔多斯市南部;低风险区主要分布在呼伦贝尔市西部、通辽市东部、锡林郭勒盟西北部、乌兰察布市北部、鄂尔多斯市中部和东部及巴彦浩特市东部。构建的评估模型总体反映了内蒙古草原旱灾综合风险水平,可为内蒙古草原灾害风险管理、应对气候变化、抗旱减灾行动提供依据。

Since regional climate change has noticeably impacted on the Inner Mongolia grassland,drought has become the primary natural disaster threatening to Inner Mongolia grassland ecosystem.Based on the theory of Natural Disaster Risk,a risk assessment model about drought disaster has been developed.Using meteorological,soil moisture,vegetation,remote sensing,socioeconomic and GIS data in 54 animal husbandry counties,8 key indicators fot risk assessment were selected from four sub-systems,including hazard of the disaster-causing factors,sensitivity of disaster-formative environments,vulnerability of disaster-bearing body and capabilities of prevention and mitigation from disaster.The weights of these risk assessment indicators were determined by analytic hierarchy process,weighted comprehensive evaluation and expert scoring method.The drought disaster risk level of grassland in Inner Mongolia was then evaluated by this model.The results show that the spatial distribution of the comprehensive drought disaster risk index presents the obvious zonal distribution with higher in the south compared with the north and higher in the east compared with the west.The area of low,medium,and high level of drought disaster risk accounts for 21.3%,37.4%and 41.3%of Inner Mongolia grassland respectively.High risk areas are mainly distributed in southern of Ordos city,central southern of Baotou city,northern of Hohhot city,central Wulanchabu city,southern of XilinGol League,central of Chifeng city,most areas of Tongliao city,southwest of Xingan league and central western of Hulunbeier city.Low risk areas are mainly distributed in eastern of Bayannaoer City,central eastern of Ordos City,western Wulanchabu city,northwestward of XilinGol League,eastern of Tongliao city and western of Hulunbeier city.The model could reflect the situation of drought disaster risk over Inner Mongolia grassland and provide a reference for disaster risk management,responding to climate change,drought resistance and disaster mitigation action.