High-resolution mapping of China’s flooded croplands

作者：Junliang Qiu, Xiankun Yang, Zihao Zheng, Paolo Tarolli · 发表于：中国科学通报：英文版 · 年份：2025 · DOI：10.1016/j.scib.2025.01.053 · 被引用次数：12 · 研究领域：Flood Risk Assessment and Management、Hydrology and Watershed Management Studies、Soil erosion and sediment transport

Mapping the flooded croplands in China. Climate change and the increasing frequency of floods have undermined China’s food security. Creating detailed maps of flooded croplands is essential to improve prevention and adopt effective adaptation initiatives. Previous large-scale flood mapping efforts were hampered by limited meteorological and hydrological data, and the susceptibility of optical satellite images to cloud cover, leading to high uncertainty when downscaled to the cropland-scale. Here, using 4968 near-real-time (NRT) Sentinel-1 SAR (S1) images (spatial resolution: 10 m), we generated China’s first set of high-resolution flooded cropland maps covering the period from 2017 to 2021. Our results demonstrate that croplands accounted for 43.8% to 49.8% of China’s total flooded areas (ranging from 82,175 km 2 to 122,037 km 2 ). We also created high-resolution flood maps specifically for rice and maize crops. The inundated rice areas ranged from 8428 km 2 to 22,123 km 2 , accounting for 22.34% to 41.91% of the annual flooded croplands, or 2.82% to 7.45% of the annual rice cropland. In comparison, the inundated maize cropland fluctuated from 2619 km 2 to 5397 km 2 , representing 5.38% to 13.56% of the annual flooded croplands. Our findings revealed extensive floods in rural areas, highlighting the urgent need to prioritize flood prevention and mitigation efforts in such regions. In light of China’s allocation of an additional 1-trillion-RMB treasury bonds for water infrastr...