Drought Risk Zoning of Double-Cropping Late Rice in Nanchang Region Based on Disaster Loss

本文基于南昌地区5个国家气象站点1978~2020年逐日气象资料、农业资料、水文资料，从干旱的致灾因子危险性、承灾害体易损性、灾损脆弱性、防灾减灾能力等4个风险因子考虑，采用专家打分法和熵权法确定各因素权重，构建基于灾害损失的双季晚稻干旱灾害风险综合评估模型，并进行干旱灾害时空格局分析。结果表明：南昌地区干旱发生概率为60%，其中1991~1994年和2000~2009年是干旱的高发期。53%的年份双季晚稻生长期间的累积降水量低于常年平均值，双季晚稻生产用水需求无法从自然降水中得到满足，干旱灾害风险非常大。综合风险区划结果显示，进贤县和新建区中南部为双季晚稻干旱灾害高风险区，南昌县中北部环鄱阳湖周边为低风险区，安义县为双季晚稻干旱灾害较低风险区。This paper was based on daily meteorological data, agricultural data and hydrological data from 5 national meteorological stations in Nanchang City during 1978-2020. Considering the four risk factors of drought, such as the risk of disaster causing factor, the vulnerability of disaster-bearing bodies, the vulnerability of disaster loss, and the ability of disaster prevention and reduction, the expert grading method and entropy-weight method were used to determine the weight of each factor, and a comprehensive assessment model of Double-cropping rice drought risk based on disaster loss was constructed. Also, the temporal and spatial distribution of drought disaster was analyzed. The results showed that the probability of drought occurrence in Nanchang was 60%, and the periods of 1991-1994 and 2000-2009 were the most frequent periods. The accumulated precipitation during the growth of Double-cropping rice was lower than the annual average in 53% of these years, so the water demand of second rice could not be met from natural precipitation, which means the risk of drought disaster was very high. According to the comprehensive risk regionalization results, Jinxian County and the central and southern parts of Xinjian District were high risk areas of second rice drought disaster, in addition the central and northern parts of Nanchang County around Poyang Lake were low risk areas, and Anyi County was lower risk areas.