研究在厄尔尼诺-拉尼娜事件的影响下西南山区泥石流灾害的时空分布特征,将有助于为泥石流灾害的预测预报提供基础指导。根据统计数据,结合GIS空间分析技术,研究西南山区泥石流灾害事件与厄尔尼诺-拉尼娜事件的时空耦合关系。研究结果显示:厄尔尼诺-拉尼娜事件年西南山区泥石流灾害暴发频率在时间上总体呈增加趋势,且拉尼娜年发生频次多于厄尔尼诺年;厄尔尼诺-拉尼娜事件年西南山区泥石流灾害暴发在空间分布上主要集中于藏东南山区、横断山区、滇东北、贵州西部、贵州西南部、滇西北、大渡河及雅砻江流域等地区;厄尔尼诺-拉尼娜年西南山区泥石流灾害点的降雨量总体上大于多年平均降雨量。西南山区泥石流灾害事件与厄尔尼诺-拉尼娜事件存在明显的关联性,研究两者关系特征,将有助于对西南山区泥石流灾害进行多方位、准确合理的预测预报。

Researching the temporal and spatial distribution characteristics of debris flow in mountainous area of southwest China under the influence of El Nino-La Nina event will be conducive to providing basic guidance for the prediction of debris flow disaster. According to statistical data, we examined the spatiotemporal coupling relationship between debris flow events and El Nino-La Nina events in mountainous area of southwest China through GIS spatial analysis approach. We found that 1) in El Nino-La Nina year, the frequency of debris flow disaster in mountainous area of southwest China increased in temporal scale, and the occurrence frequency in La Nina year was larger than that in El Nino year; 2) in spatial scale, under El Nino and La Nina events, debris flow disaster was mainly concentrated in mountainous area of southeast Tibet, Hengduan Mountains, northeast Yunnan Province, west and southwest parts of Guizhou Province, northwest Yunnan Province, Dadu River basin, and Yalong River basin, etc; 3) in El Nino-La Nina year, rainfall amount in the debris flow stricken area was larger than multi-year average rainfall in general. We conclude that debris flow events in mountainous area of southwest China are evidently correlated with El Nino-La Nina events.