Mapping Early, Middle and Late Rice Extent Using Sentinel-1A and Landsat-8 Data in the Poyang Lake Plain, China.

摘要: Areas and spatial distribution information of paddy rice are important for managing food security, water use, climate change. However, there many difficulties in mapping rice, especially multi-season rainy regions, including differences phenology, the influence weather, farmland fragmentation. To resolve these problems, a novel approach based on Sentinel-1A Landsat-8 data is proposed. First, were enhanced fact that backscattering coefficient varies according to its growth stage. Second, cropland was NDVI winter lower than growing season. Then, areas extracted using K-Means unsupervised classifier with images. Third, further improve classification accuracy, utilized optimize by must be planted cropland. Classification accuracy validated ground-data from 25 field survey quadrats measuring 600 m × m. The results show that: planting effectively method adjusted early area 1630.84 km2, middle 556.21 late 3138.37 km2. overall 98.10%, kappa 0.94.