Estimation of Photosynthetic and Non-Photosynthetic Vegetation Coverage in the Lower Reaches of Tarim River Based on Sentinel-2A Data

Estimating the fractional coverage of photosynthetic vegetation (fPV) and non-photosynthetic (fNPV) is essential for assessing growth conditions in arid areas monitoring environmental changes desertification. The aim this study was to estimate fPV, fNPV bare soil (fBS) lower reaches Tarim River quantitatively. acquired field data during September 2020 obtaining fBS. Firstly, six indices (PVIs) (NPVIs) were calculated from Sentinel-2A image data. PVIs include normalized difference index (NDVI), ratio (RVI), adjusted (SAVI), modified (MSAVI), reduced simple (RSR) global environment (GEMI). Meanwhile, (NDI), tillage (NDTI), senescent (NDSVI), (STI), shortwave infrared (SWIR32) dead fuel (DFI) constitutes NPVIs. We then established linear regression model different NPVIs fNPV, respectively. Finally, we applied GEMI-DFI analyze spatial seasonal variation fPV area 2020. results showed that GEMI revealed best correlation coefficient (R2) 0.59, while DFI had R2 = 0.45. accuracy fBS based on determined as by are 0.69, 0.58 0.43, consistent with phonological development characteristics area. concluded application estimation sufficiently significant its ecological functions areas.