北京山区暴雨泥石流激发雨量条件

发布时间：2018-03-04 18:45

本文选题：暴雨　切入点：泥石流　出处：《中国水土保持科学》2017年05期 　论文类型：期刊论文

【摘要】：泥石流是北京山区常见的一种山地灾害,也是威胁山区生态环境的头号安全问题。分析该区的泥石流激发雨量条件对于该区山洪泥石流预测预报具有指导意义。笔者搜集18场降雨数据,分析该区泥石流的激发雨量特征。结果表明:激发降雨的峰值降雨时段介于3~9 h,峰值时段平均降雨强度达22.6~50.0 mm/h,累积雨量达91.9~350.0 mm,峰值降雨时段雨量占累积雨量的63.9%~100.0%,这说明激发泥石流的降雨过程具有历时短、雨量集中、突发性强的特点。用修正后的李氏法进行雨场分割,得到该区泥石流激发的降雨强度-历时和累积雨量-历时关系。最后,以密云区北部山区为例分析3期植被盖度和泥石流激发雨量条件。归一化植被指数和像元线性分解模型分析表明,1989—1991、2004—2005和2011—2012年植被覆盖度分为64.48%、68.57%和72.48%;相应的泥石流雨量激发条件也随着植被覆盖度的增加而增大,可见植被恢复盖度对泥石流的形成具有一定影响。本文统计分析得出的泥石流激发雨量条件可为该区山洪泥石预测预报和监测预警指标选取提供参考。
[Abstract]:Debris flow is a kind of mountain disasters in Beijing mountainous areas, the number one security problem is a threat to the ecological environment of the mountain area. Analysis of the debris flow excited rainfall has guiding significance for the prediction of the debris flow. The author collects 18 rainfall data, analyze the excitation characteristics of the area rainfall debris flow. The results show that the rainfall the peak period of rainfall from 3~9 to h, the average intensity of rainfall peak periods up to 22.6~50.0 mm/h, the accumulated rainfall of 91.9~350.0 mm, the peak period of rainfall rainfall accounted for cumulative rainfall of 63.9%~100.0%, indicating that the rainfall debris flow excited has short duration, rainfall concentrated, characteristics of sudden strong rain. The field division with Lipschitz modified, get the rainfall intensity duration and cumulative rainfall induced debris flow duration. Finally, in the mountain area in the northern Miyun for example analysis of 3 vegetation coverage and debris flow Stimulate the rainfall conditions. The NDVI and the pixel linear decomposition model analysis showed that the 1989 - 19912004 - 2005 and 2011 - 2012, the vegetation coverage is 64.48%, 68.57% and 72.48%; the corresponding rainfall debris flow excitation conditions also increases with the increase of vegetation coverage, vegetation coverage can see has a certain influence on the formation of debris flow. This paper analyzed the statistical conditions for the excitation of debris flow rainfall flood debris forecasting and monitoring of early warning indicators selected to provide reference.

【作者单位】：北京林业大学水土保持国家林业局重点实验室;北京林业大学北京市水土保持工程技术研究中心;北京林业大学水土保持学院;
【基金】：国家自然科学基金“北方土石山区低黏度泥石流起动机理研究”(41702369)
【分类号】：P642.23

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