National-Scale Sub-meter Mapping of Spartina alterniflora in Mainland China 2020

The first 2020 national-scale sub-meter Spartina alterniflora (S. alterniflora) map of Mainland China (CM-SSM) was generated using an Object- and Sub-meter-enhanced Pixel-based Phenological Feature (OSPPF) composite method. Based on this map, a total of 148,072 S. alterniflora patches were identified, covering a total area of 59,371 hectares. The CM-SSM achieved an overall accuracy of 96.76% and an F1 score of 0.95, demonstrating excellent performance in delineating patch boundaries, detecting small patches, and capturing internal structural details. This map enhances scientific understanding of S. alterniflora invasion dynamics, provides a solid foundation for carbon accounting, and supports evidence-based management and restoration of coastal wetlands.