Remote Sensing Monitoring of Debris Flow Area in Dabaini River Basin of Xiaojiang, Dongchuan County

Abstract

Dongchuan County in Yunnan Province, China is a typical debris flow area in China and even in the world. The occurrence of debris flow has a great impact on the land cover. At present, remote sensing monitoring has been widely used in land use surveys due to its characteristic of non-directly contacting with the measured objects. Therefore, the use of remote sensing technology is a safe and efficient method for land cover surveys in debris flow area. Based on the 2016 Landsat remote sensing image, this paper selected the tributary of Xiaojiang River-Dabaini River Basin in Dongchuan County as the research object, monitored the land cover in the basin through the remote sensing interactive interpretation and then revealed the current status of land use. The results showed that: (1) According to the land cover of the Dabaini River Basin presented by remote sensing image, the land in the basin can be divided into two categories: debris flow area and non-debris flow area. (2) The remote sensing interpretation marks were established for debris flow area. The debris flow area was divided into three sections: source section, with an area of 174.70 ha; circulation section, with an area of 94.87 ha; accumulation section, with an area of 98.74 ha. Different sections exhibited different shapes and structural features. (3) The land use of non-debris flow area was divided into four types, including 767.61 ha of cultivated land, 682.33 ha of forest land, 112.78 ha of construction land, 414.87 ha of bare land. The spatial distribution of four land use types presented a variety of features. (4) However, there was still an irrational land use in the Dabaini River Basin, such as free to occupy cultivated land and indiscriminate felling of trees which caused inefficient and unsustainable land use. This phenomenon should be controlled and improved in order to reduce soil erosion and optimize the allocation of land resources, to make the land use in the Dabaini River Basin be intensive and rational. This paper has an important scientific significance for the study of debris flow land cover monitoring and land use evaluation in the Dabaini River Basin.