基于GIS的湖南省山洪沟提取技术及其应用

Extraction and Application of Flash Flood Ditch in Hunan Province Based on GIS

摘要: 本文基于GIS空间分析技术进行流域信息分析，结合坡度、地形起伏度等地形特征，利用逆流原理对湖南省山洪沟边界信息进行提取，结果表明：1) 湖南省山洪沟多分布在湖南省西北部、南部和中部山区。与降水分布进行对比，发现这些地区降水分布相对集中，且出现强降水的概率较大，出现山洪灾害的风险较高。2) 对山洪沟预测指标进行等级分级，用不同等级值反映了山洪灾害发生的概率，可以看出提取的山洪沟位置信息与实际发生山洪灾害的位置有很好的对应关系。说明山洪沟的分布能在一定程度内反映出山洪灾害的发生地点。3) GIS提取结果与历史普查的山洪灾害发生区域进行叠加分析，相似度较高，较好的验证了山洪沟提取的可靠性。

Abstract: In this paper, GIS spatial analysis technique is based on watershed information analysis, combined with slope, terrain ruggedness, and other terrain features, to extract flash floods ditch of Hunan. The results showed that: 1) Flash floods ditches are located in mountainous areas of northwestern, southern and central in Hunan Province. Compared with the distribution of precipitation, rainfall distribution is concentrated in these areas, and both the probability of heavy precipitation and risk of flood disasters are higher. 2) Used different levels of value to reflect the probability of flash floods disasters, we can see that it has a good relationship between flash flood position by extracted and the actual location of flood disasters. To some extent, the distribution of flash floods ditch also has been reflected the occurrence of flood disasters in place. 3) The results can reflect the Flash floods ditch extraction reliability compared with the history fact of flash flood disasters.