Abstract:Against the backdrop of global climate change, the increasing frequency of extreme weather events poses serious threats to agricultural production. As a major maize-producing region in China, Northeast China faces the challenge that key growth stages of maize overlap with the period of frequent regional heavy rainfall, leading to recurrent waterlogging disasters that severely endanger grain security. High-resolution remote sensing technology offers an effective means for rapid disaster monitoring. However, existing methods predominantly rely on water feature extraction from optical and radar imagery, which depends on prior knowledge of surface features and shows limited effectiveness in identifying "implicit" waterlogging areas where the canopy is not submerged. This is particularly evident in the inadequate accuracy and boundary consistency for detecting small-scale affected areas. To address these issues, the first high-resolution semantic segmentation dataset for implicit maize waterlogging disasters was constructed based on 3 m Planet and 4 m State Grid remote sensing images, filling the gap in high -quality labeled data. Furthermore, a DSA - DeepLab semantic segmentation model was proposed, which incorporated a DenseASPP module and an adaptive feature fusion module embedded with selective kernel attention, thereby effectively enhancing the detection capability for small targets and complex boundaries. Experimental results demonstrated that the proposed model achieved mean intersection over union and mean pixel accuracy of 80.70% and 88.60%, respectively, representing improvements of 1.63 percentage points and 1.67 percentage points over the baseline model. Specifically, for implicit waterlogging, the IoU and recall rates were increased by 2. 72 percentage points and 3. 38 percentage points, respectively, outperforming that of several mainstream semantic segmentation methods. Additionally, to address the memory overflow issue caused by large-size image inputs during inference, an overlapping patch extraction-edge ignoring strategy was adopted, effectively suppressing stitching artifacts and boundary errors. This research achieved high-precision automated extraction of implicit maize waterlogging disasters, providing reliable technical support for disaster assessment and agricultural insurance claims.