Evaluation of meltwater erosion intensity in Naqu district based on principal components analysis
FENG Junyuan1,2, LU Yan3, CAI Qiangguo1, LI Zhaoxia2, SUN Liying1*
(1 Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;2 College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, Hubei, China; 3 School of Water Conservancy of Environment,Zhengzhou University, Zhengzhou 450001, Henan, China)
Abstract:
Ten influencing factors were selected as indicators to evaluate the meltwater erosion intensity in Naqu district, as wind speed, total sunshine, annual range of temperature, relative humidity, slope gradient, aspect, NDVI, soil erodibility, elevation and snow change factor. The dominant influencing factors on meltwater erosion intensity were extracted by the method of principal components analysis, and the index of meltwater erosion intensity for each evaluation unit was calculated under different environmental backgrounds. Moreover, the meltwater erosion degrees were evaluated based on GIS software and the spatial distribution characteristics of meltwater erosion were analyzed in Naqu district. The results showed four dominant influencing factors on meltwater erosion, as geomorphology factor, climate factor, soil factor and snow change factor. Six degrees were classified for the meltwater erosion intensity in the study area. The percentage of areas with different meltwater erosion intensity degrees are: extremly slight erosion(40.0%), extremly serious erosion(24.0%), medium erosion(16.0%), slight erosion (8.0%), violent erosion(7.0%), serious erosion(5.0%).
KeyWords:
meltwater erosion; principal components analysis; GIS; Naqu district; strength evaluation
