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Updated: May 16, 2026

Investigating the Relationship between Sea Surface Chlorophyll and Major Features of the South China Sea with Satellite Information
Published on: June 13, 2020
A 30 m vegetation map for the source regions of the Yangtze and Yellow Rivers from 2020-2025 ground surveys
Defu Zou1, Xiaodong Wu2,3, Guojie Hu1
1Cryosphere Research Station on Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
Abstract:
An up-to-date vegetation map is essential for characterizing current ecosystem conditions in the source regions of the Yangtze and Yellow Rivers (SRYYR) under ongoing climate change. Here, we release a region-specific 30 m vegetation type dataset that represents typical conditions in the early 2020s. The map was created using systematic ground survey data from 1,168 georeferenced sites collected from 2020 to 2025. A random forest classifier was trained using Landsat imagery and environmental predictors to generate the vegetation type map. Sample representativeness was quantified by comparing predictor distributions between survey sites and the study area. The Euclidean distance ranged from 2.99% to 8.85% and Pearson's r from 0.59 to 0.97. The final map had an overall accuracy of 79.56% and a Cohen's kappa of 0.74. Unlike existing plateau-wide products, this dataset explicitly delineates alpine swamp meadows (ASMs) and improves the spatial representation of alpine shrublands (ASHs), providing an updated baseline for permafrost-vegetation coupling and related ecohydrological processes in the SRYYR.
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