彭阳县玉米干旱风险评估与区划

［目的］彭阳县玉米种植区域广泛，但干旱灾害频发，常造成玉米减产甚至绝收。因此加强彭阳县玉米干旱灾害风险评估与区划有着重要的现实意义。［方法］利用彭阳县气象数据以及地形、土壤类型等数据，基于灾害风险评估原理，运用相关分析法、层次分析法，结合GIS技术对彭阳县玉米干旱灾害进行风险评估与区划。［结果］彭阳县北部及西部降水少，玉米干旱危险性较高，南部和东部降水多，玉米干旱危险性较低； 草庙乡土壤保水性最差，玉米干旱敏感性最高，白阳镇、城阳乡土壤保水性最好，玉米干旱敏感性最低； 新集乡、白阳镇、草庙乡耕地面积所占总面积最大，玉米干旱暴露性最高，小岔乡耕地面积所占总面积最小，玉米干旱暴露性最低； 白阳镇灌溉田比例最高，玉米防灾减灾能力最强，彭阳北部1镇3乡都没有灌溉农田，玉米防灾减灾能力最弱。综合来看，彭阳县西北部玉米干旱综合风险较高，西南部和东南部风险较低，其余地区以中等风险为主。［结论］玉米干旱灾害风险评估与区划是科学认识农业干旱的基础，为科学管理以及制定合理有效的防灾减灾方案提供科学参考。

DROUGHT RISK ASSESSMENT AND REGIONALIZATION OF MAIZE IN PENGYANG COUNTY

Pengyang county has extensive maize planting area, but it suffers a lot from frequent drought disasters. Therefore, it is of great practical significance to strengthen the study in drought risk assessment and zoning of maize in Pengyang county. Based on meteorological data, terrain data and soil types data, this research assessed and zoned drought risk for maize cultivated in Pengyang county by application of natural disaster risk assessment principles, correlation analysis method, analytic hierarchy process and Geographic Information System technic. The results showed that the drought risk of maize was higher in the northern and western parts of Pengyang county where there were few precipitations while it was much lower in the southern and eastern parts that with relatively more precipitations. The soil moisture retention in Caomiao township was the worst while its drought sensitivity of maize was the highest. The soil moisture retention in Baiyang town and Chengyang township was the best while their drought sensitivity of maize was the lowest. The total area of cultivated land in Xinji township, Baiyang town and Caomiao township was the largest, and their drought exposure of maize was the highest. The total area of cultivated land in Xiaocha township occupied the smallest area, and its drought exposure of maize was the lowest. It had the highest proportion of irrigated fields in Baiyang town, and its ability to minimize the risk of disasters and their damages was the best. There had no irrigated farmland in one town and three townships in the northern part of Pengyang county where the ability to minimize the risk of disasters and their damages was weakest. Overall, the comprehensive risk of drought of maize in northwestern Pengyang county was relatively high while the risk in the southwest and southeast was relatively low, and the remaining areas were mainly moderately risky. The risk assessment and zonation of maize drought is the basis for scientific understanding of agricultural drought, which would provide scientific references for scientific management and formulation of reasonable and effective disaster prevention and reduction programs.