[1]CUI Wanxin,LI Jinrong,SI Qiancheng,et al.Research on Extraction Method of Desert Shrub Coverage Based on UAV Visible Light Data[J].Research of Soil and Water Conservation,2021,28(06):175-182.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
28
Number of periods:
2021 06
Page number:
175-182
Column:
Public date:
2021-10-10
- Title:
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Research on Extraction Method of Desert Shrub Coverage Based on UAV Visible Light Data
- Author(s):
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CUI Wanxin1,LI Jinrong2,SI Qiancheng1,WANG Ru1,LUO Xiangying1,YANG Feng1,LI Yingkun1
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(1.Inner Mongolia Agricultural University,Hohhot 010018,China; 2.Institute of Pastoral Water Science,Ministry of Water Resources,Hohhot 010020,China)
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- Keywords:
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UAV; vegetation index; desert shrubs; visible light data
- CLC:
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TP79; Q948
- DOI:
-
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- Abstract:
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In order to improve the accuracy of desert vegetation extraction,taking the shrubs on the east bank of the Ulanbu and desert sections of the Yellow River as the research object,based on the spectral characteristics of the desert shrubs in the visible light band,from the perspective of index,threshold method and image resolution,we compared the characteristics of difference vegetation index(VDVI)and green index(EXG),normalized green-blue difference index(NGBDI),normalized green-red difference index(NGRDI),red-green ratio index(RGRI),excessive green minus red index(EXG-EXR)of 6 types of plants and analyzed the influencing factors. The results showed that in the desert shrub study area,the histograms of EXG and EXG-EXR indices were bimodal,and the rest were non-bimodal; for the peak characteristics,it was feasible to use the histogram threshold method and the threshold iteration method to calculate the threshold; the average extraction accuracy of VDVI,EXG-EXR and NGBDI was 98.11%,87.25% and 84.73%,respectively,and the Kappa coefficients were greater than 0.7(K>0.61),which was suitable for extracting desert shrub vegetation,and the extraction accuracy of other vegetation indices was less than 80%; when the aerial image had uneven light and dark textures,all the index grayscale images except the NGBDI index grayscale image showed shadow texture,but only the EXG index extraction accuracy was affected by the shadow texture,and the accuracy was reduced from 77.03% to 64.88%; flying heights of 40 m and 50 m were the preferred altitudes for field surveys through integrating the effect of ground pixel resolution and image stitching effect(brightness and completeness)on the extraction accuracy.