Mapping Spatially Seamless Fractional Vegetation Cover over China at a 30-m Resolution and Semimonthly Intervals in 2010-2020 Based on Google Earth Engine  

作　　者：Tian Zhao Xihan Mu Wanjuan Song Yaokai Liu Yun Xie Bo Zhong Donghui Xie Lingmei Jiang Guangjian Yan 

机构地区：[1]State Key Laboratory of Remote Sensing Science,Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China [2]Beijing Engineering Research Center for Global Land Remote Sensing Products,Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China [3]State Key Laboratory of Remote Sensing Science,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100101,China [4]Key Laboratory of Quantitative Remote Sensing Information Technology,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China [5]State Key Laboratory of Earth Surface Processes and Resource Ecology,Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China [6]College of Arts and Sciences,Beijing Normal University,Zhuhai 519087,China

出　　处：《Journal of Remote Sensing》2023年第1期444-462,共19页国际遥感学报（英文）

基　　金：financially supported by the National Natural Science Foundation of China(grant nos.42090013,42271338,and 41871230).

摘　　要：Fractional vegetation cover(FVC)is a critical biophysical parameter that characterizes the status of terrestrial ecosystems.The spatial resolutions of most existing FVC products are still at the kilometer level.However,there is growing demand for FVC products with high spatial and temporal resolutions in remote sensing applications.This study developed an operational method to generate 30-m/15-day FVC products over China.Landsat datasets were employed to generate a continuous normalized difference vegetation index(NDVI)time series based on the Google Earth Engine platform from 2010 to 2020.The NDVI was transformed to FVC using an improved vegetation index(VI)-based mixture model,which quantitatively calculated the pixelwise coefficients to transform the NDVI to FVC.A comparison between the generated FVC,the Global LAnd Surface Satellite(GLASS)FVC,and a global FVC product(GEOV3 FVC)indicated consistent spatial patterns and temporal profiles,with a root mean square deviation(RMSD)value near 0.1 and an R^(2) value of approximately 0.8.Direct validation was conducted using ground measurements from croplands at the Huailai site and forests at the Saihanba site.Additionally,validation was performed with the FVC time series data observed at 151 plots in 22 small watersheds.The generated FVC showed a reasonable accuracy(RMSD values of less than 0.10 for the Huailai and Saihanba sites)and temporal trajectories that were similar to the field-measured FVC(RMSD values below 0.1 and R^(2) values of approximately 0.9 for most small watersheds).The proposed method outperformed the traditional VIbased mixture model and had the practicability and flexibility to generate the FVC at different resolutions and at a large scale.

关 键 词：MAPPING ENGINE Spatial 

分 类 号：V24[航空宇航科学与技术—飞行器设计]