Distribution And Causes Of The Landslide And Debris Flow Space-based Remote Sensing Interpretation

Gravity erosion is a type of soil erosion,the study area-Heihui River Basin is in the northwest region of Yunnan,and middle-mountain and alpine canyon are major for landform in the area.The gravity erosion is widespread,and what is more,most of the landslide and debris flow in the Heihui River Basin.Clarify these two gravity erosion in the form of the distribution of the study area,there are great significance about the estimated amount of soil erosion and preventing disaster.The paper apply the ETM~+ data of the latest series Landsat7 which is currently the most widely used landsatellite as the major data sources.ETM~+ remote sensing images are processed in the paper,and the last remote sensing image resolution is improved from 30m to 15m;On this basis,the use of remote sensing image and the characteristics of the landslide and debris flow,and combine the results of remote sensing interpretation on environmental background,to obtain remote sensing interpretation on the landslide and debris flow in the study area.The distribution as follows:landslide and debris flow distribution are similar to a inclined "Y"-shaped strip,and most of its location is at the sides of fractures in the study area.According to statistics,there are 62 debris flow ditches,distribution density of debris flow is 14.2/1000km~2,and there are 56 landslides,distribution density of landslide is 12.8/1000km~2.From distribution density of landslide and debris flow,the southern distribution density is over the northern in the Heihui River Basin.At the same time,the reason on the landslide and debris flow of the study area is preliminarily analyzed in the paper,The analysis from the macro level shows that the landslide and debris flow in the study area mainly are controlled by two fractures,which are called Longpan-qiaohou fracture and Tongdian-weishan fracture,moreover,the strength and highly frequency earthquake activity,high concentrated rainfall and heavy rain during the rainy season,and unreasonable human activities,such as the reasons both inside and outside,which effect the development of the landslide and debris flow in the Heihui River Basin.The reason is analyzed about typical landslide and debris flow in Sangbulao village,which shows the landslide and debris flow disaster is controlled by fracture from macro level,from the micro level analysis,that is synthetically caused by hydrology,topography,rainfall,soil,vegetation, land use,and human activities and so on.Although the landslide and debris flow are interpreted from remote sensing image on the study area,and the reason about the landslide and debris flow is analyzed in the paper,the interpretation and analysis are all preliminary,the two aspects are needed more adequate information to more research.Summarize the above research results,at last,some reasonable suggestion are putted forward to prevention of the landslide and debris flow for the area in the paper.