江西省森林冰冻灾害风险时空特征

Spatial-temporal Characteristics of Forest Freezing Disasters in Jiangxi Province

雨雪冰冻事件是影响中国南方地区农林业生产的主要气象灾害之一。本研究基于负积温与气温低于0℃的降水量与实际观测的冰雪冻害发生频次之间相关关系分析基础上,确定影响江西省森林冰冻灾害的主要气象因子,并采用模糊数学的方法,计算森林冰冻灾害风险评估因子。同时,应用Morlet小波分析和Mann-Kendall突变分析方法,分析江西省森林冰冻灾害风险的年际变化规律。基于负积温与最低气温低于0℃的当日降水量的平均隶属度、纬度和海拔的相关关系,构建了江西森林冰冻灾害风险区划地理函数,利用ArcGIS空间分析工具,采用自然断点法对风险等级进行区划。结果表明,1955-2018年,江西省冰冻灾害发生次数总体呈现减少趋势,冰冻灾害发生与负积温和当日降水量密切相关,利用负积温与低于0℃的降水量的平均隶属度可以有效地评估森林冰冻灾害风险;江西省森林冰冻灾害风险最为严重的区域主要位于武夷山脉、九岭山脉、罗霄山脉、雩山山脉以及庐山等平均海拔>1000 m的山区。该结论可为江西省森林资源管理提供科学依据。

Freezing rain and snow that occurs frequently in the southern China is one of the main meteorological disasters in the region.Based on a multiple regression model,this study established the relationship between actually recorded frequency of freezing rain and snow and environmental factors,including negative accumulative temperature,present-day precipitation,elevation,latitude and other factors.Based on the relationship,this study further developed the freezing damage risk distribution maps and identified the leading factors affecting freezing damage risks.In addition,the Morlet wavelet analysis and Mann-Kendall trend test were applied to analyze the interannual variation patterns of freezing damage risks.The results indicated that the frequency of freezing disasters in Jiangxi Province declined from 1955 to 2018.The occurrence of freezing disasters was positively correlated with negative accumulative temperature and the precipitation blow 0℃.Based on the membership degree of freezing disasters,this study developed the geographic zoning function for freezing disaster risks of forests in Jiangxi Province,and further classified five levels of freezing disaster risks using spatial analysis tools in ArcGIS.The most serious risk of freezing disaster occurred mainly in the region above 1000 m in the Wuyi Mountains,Jiulin Mountains and Luoxiao Mountains,Yushan Mountains and Lushan Mountain.This study will provide scientific guidance to manage forest resources and reduce the impacts of extreme climate events in Jiangxi Province.