县域尺度下的宝鸡市农业洪水灾害脆弱性评价及区划

为探究农业洪水灾害发生机理和降低洪水灾害对农业生产的不利影响，以宝鸡市为例，利用辖区内2014年降水数据与2015年社会经济统计资料，依据自然灾害脆弱性理论，从易损性和适应性2个因子着手，选取了年降水量等12个分指标，构建了宝鸡市农业洪水灾害脆弱性评价指标体系，运用均方差赋权法确定权重，利用ArcGIS 10.2技术以县域尺度视角对研究区农业洪水灾害脆弱性进行了综合评价与区划。结果表明：（1） 高易损性区主要集中在岐山县、金台区等年降水量较高且耕地比重较大的区县。（2） 高适应性区主要包括渭滨区、金台区等经济发达地区。（3） 高脆弱性区为太白县、千阳县；较高脆弱性区为陇县、麟游县、岐山县、扶风县；中等脆弱性区为陈仓区、凤翔县；低脆弱性区为金台区、渭滨区、眉县、凤县。整体来看，宝鸡市农业水灾高脆弱区集中分布在辖区东北部，宝鸡市政府及有关部门应加强水灾风险研究，根据各区县的地理环境特征和经济发展水平来因地制宜调整土地利用结构和农业种植结构，重视防洪工程建设，降低农业水灾脆弱性以减轻农业洪水灾损。

Assessment and zoning of vulnerability of agricultural flood diaster in Baoji City based on county scale

Floods are a natural phenomenon.The frequency of flooding disasters will increase if there is an imbalance between people and the land.Agricultural floods occur because of the interaction between natural and socio-economic factors.The vulnerability and adaptability of the disaster-affected bodies affect the vulnerability of agricultural floods.As a critical agricultural city and population gathering area in the western part of the Guanzhong area,Shaanxi Province,China,the landform types of Baoji City in the area are complex and diverse.Owing to the inter-annual and seasonal fluctuations in the East Asian summer monsoon,the flood disasters in Baoji City are frequent and serious,and the damage caused by flood disasters is second only to drought disasters.Therefore,it is critical to conduct a risk assessment and zoning research of agricultural floods.Based on the precipitation data in 2014 and the socio-economic statistics in 2015,this study initially discussed with the vulnerability and adaptability factors and selected 12 subindexes,including annual precipitation.We constructed the index system and evaluation model for the vulnerability assessment of agricultural flood disasters in Baoji City and determined the weight by using a mean-variance weighting method.The vulnerability of agricultural flood disasters in the study area was comprehensively evaluated and zoned using ArcGIS 10.2 technology from the perspective of a county scale.Results show the following:(1) The high-vulnerability area is concentrated in the districts and counties with high annual precipitation and the large proportion of cultivated land in Daishan County and Jintai District.(2) Highly adaptable areas include economically developed areas such as Weibin District and Jintai District.(3) High-vulnerability areas are Taibai County and Qianyang County.The higher vulnerability areas are Jixian,Linyou,Daishan,and Fufeng,the medium fragile areas are the Chencang District and Fengxiang County,and the low vulnerability areas are the Jintai District,Weibin District,Meixian County,and Feng County.Overall,the high fragility areas of agricultural floods in Baoji City are concentrated in the northeastern part of the county.Agricultural floods are generally manifested in areas such as the Weihe River and Qianhe River,the mountain river catchment areas,channel coasts,and closed low-lying basins.The Baoji Municipal government and relevant departments should formulate the necessary disaster prevention and mitigation measures to reduce agricultural flood damage based on the characteristics of the cultivated environment,economic development level,population distribution pattern,and land-use structure of each district and county.Among them,ecological disaster reduction is a practical and effective measure to cope with flood disasters.The zoning results are consistent with the disaster situation in Baoji City,which could provide a reliable reference for the comprehensive management of regional agricultural floods.As there are few studies on flood disasters in small and medium-scale areas with complex topographical conditions of the past,this study is aimed at Baoji City,a mesoscale area with complex topographical and geomorphological conditions in a typical monsoon climate zone.We analyzed and evaluated the vulnerability of local agricultural flood disasters and proposed countermeasures.We believe that the occurrence of agricultural floods in small-scale regional areas is characterized by locality,suddenness,uncertainty,and difficulty in forecasting.The early warning,forecasting,and monitoring are of great practical significance for reducing the vulnerability and mitigating the actual damage.