The band ratio and density slice method based on RapidEye remote sensing images and its application to investigation of karst rocky desertification:A case study in Heqing county,Yunnan Province
TU Jie-nan
YANG Liang
LIANG Li-xin
TONG Li-qiang
GUO Zhao-cheng
LIU Ting
HE Peng
Abstract：Heqing county is located in northwestern Yunnan Province,the southwestern margin of the Yang-zi platform,E 100°01′~100°29′and N25°57′~26°42′,the southern end of the traverse mountains in western Yunnan and the east of the Yunling range.Karst mountainous plateaus and basin landforms dominate this region with a total land area of 2,323.54 km2 ,including exposed carbonate rock 741 km2 ,representing typi-cal karst rocky desertification (KRD for short).The research on KRD is of great significance to soil erosion management and improvement of geological and ecological environments in Heqing county.The KRD inter-pretation based on high-resolution remote sensing images is one of the important methods in large-scale in-vestigations to this phenomenon.At present,visual interpretation is still the main approach for KRD inter-pretation with high-resolution remote sensing images.To improve the accuracy and speed of the KRD inter-pretation,a method of band ratio and density slice for KRD investigation is proposed.This study took Heqing county as an example and RapidEye multispectral remote sensing image of 201 1 as information source.On the basis of standard spectral curves of limestone and conifer-meadow mix,and combining with analyzing profile curves of different rock coverage DN values,we applied the band ratio and density slice method to investigation of large-scale KRD in Heqing county.After indoor interpretation,we went to the field to validate the accuracy of the interpretation results and modify them.At last,we obtained the KRD da-ta of Heqing county.The investigation results show that the area of KRD in Heqing county is 188.82 km2 , which accounts for 8.13% of the whole county area and 25.48% of the karst area.The area of severe KRD is 10.31 km2 ,which accounts for 5.46% of the total KRD area.The moderate KRD area is 42.28 km2 ,which accounts for 22.39% of the whole.And the mild KRD area is 136.23 km2 ,accounting for 71.15%.Through the field validation,the correct ratio of KRD interpretation is 84%,which can meet the interpretation de-mand and the technical specification.So it is concluded that the band ratio and density slice method can be applied to large-scale KRD remote sensing investigation effectively.
Keywords：remote sensing interpretationrocky desertificationdensity sliceband ratio
Publication Date：2015-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：10( 298-307 )