Abstract:

In this paper, the 100 m grid spatial weather data were obtained from Kringing interpolation method based on the daily weather data including precipitation, sunshine duration, maximum and minimum air temperature, wind velocity and water vapor pressure during summer maize growing season (June 11 to September 30) at 118 weather stations of He’nan Province from 1981 to 2010. The Kringing interpolation method was optimized by cross validation. Water deficit indexes during different stages of summer maize were calculated by using the interpolated weather data. Drought dangerousness index was formed by water deficit index of different stages. The summer maize planting area retrieval from remote sensing, averaged yield reduction rate and social economic condition were used as the evaluation index for exposure, vulnerability and disaster resistant ability, respectively. The integrated risk evaluation model was established using the above indexes for risk assessment and division of summer maize drought in He’nan Province, and the whole province was divided into three risk grades. The low risk area mainly located in east and southeast regions of He’nan, while the high risk area mainly distributed in Zhoukou, Zhumadian and northwest part of He’nan, and the rest regions were moderate risk, which presented the similar spatial distribution with historic frequency of summer drought. The zonation results fully considered the summer maize plant area and land use information, therefore it had highly precision and could provide a reference for prevention and mitigation of summer maize drought disaster.

Key words:  summer maize, drought disaster, risk zonation, risk evaluation model, water deficit

摘要：

利用1981—2010年河南省118站夏玉米生长季（6月中旬—9月下旬）逐日降水量、日照时数、最高最低气温、平均风速、平均水汽压等气象资料，通过交叉验证确定较优的克里金插值方法，进行基于百米网格的空间要素插值。对插值后的数据进行空间运算，计算各生育阶段夏玉米水分亏缺量，建立全生育阶段干旱危险性指标；以基于遥感反演的夏玉米种植面积作为暴露性指标；以多年平均减产率作为脆弱性指标；以近6 a社会经济条件构建综合抗灾能力指标；在此基础上综合各项风险要素建立干旱综合风险评估模型。最后，利用风险评估模型结合土地利用信息进行河南省夏玉米干旱综合风险精细化区划，把河南全省划分为高、中、低3个风险区，低风险区主要位于豫东和豫东南，高风险区主要分布在周口、驻马店及豫西北地区，其它地区为中度风险区，与历史夏季旱灾发生频次的空间分布趋势基本一致。区划结果充分考虑夏玉米种植面积和土地利用信息，具有较高的精度，可为夏玉米干旱灾害防御提供参考依据。

关键词: 夏玉米, 干旱灾害, 风险评估模型, 风险区划, 水分亏缺量