江西省干旱洪涝的时空变化特征分析

Analysis of spatiotemporal trend characteristics of droughts and floods in Jiangxi Province

根据1981-2010年江西省83个气象观测站的降水统计资料,采用Z指数作为旱涝等级评价的划分标准,分析了江西省旱涝灾害出现的频率,并采用趋势分析、Mann-Kendall检验、小波分析等方法,探讨了江西省旱涝灾害发生的空间、时间变化趋势。结果表明,江西省近30年旱涝灾害较为严重,整体上表现为增趋势,且存在涝-旱的交替循环转换,年代际变化比较明显。旱涝事件的周期振荡规律显著,洪涝灾害具有16年、9年和5年的周期,干旱灾害具有18年和5年的周期。从旱涝灾害频次的空间分布上来看,干旱主要发生在江西省和福建省交界的武夷山西侧和赣南,而洪涝主要发生在赣北沿九江一带和吉泰盆地。

With the precipitation data observed at 83 meteorological stations in Jiangxi Province during 1981 to 2010, the trends of frequency and spatiotemporal change of droughts and floods was analyzed using Mann-Kendall tests, wavelet analysis and IDW interpolation based on Z-index classification. Resuhs show that, droughts and floods in recent 30 years present an overall seriously increasing trend, and flood and drought change alternately with an obvious inter-decadal variation. Periodic oscillations of drought-flood events are significant, with floods＇ return periods of 16, 9 and 5 years, and droughts＇ return periods of 18 and 5 years. Spatial distribution of the frequencies of droughts and floods shows that, droughts mainly occur at the juncture of Jiangxi Province and Fujian Province , i.e. the west side of Wuyi Mountain and southern Jiangxi Province, while floods mainly occur in the north of Jiangxi along the Jiujiang region and Guiter basin.