Spatial Data-based Analysis of Inland Wetland Distribution in the Han River Basin

The purpose of this study is to construct a spatially structured dataset that characterizes the distribution patterns of inland wetlands in the Han River Basin and to provide baseline information that supports type-specific, size-specific, and region-specific management and conservation planning. The analysis identified 620 inland wetlands with a total area of 271.41 km<sup>2</sup>, corresponding to 23.5% of the national inland wetland inventory (2,704 sites, 1,154.6 km<sup>2</sup>). Riverine wetlands constituted the largest share of the basin’s wetlands, accounting for 339 sites and 237.16 km<sup>2</sup> (87.4% of the total area). Although 350 wetlands smaller than 0.1 km<sup>2</sup> represented 56.5% of all sites, they occupied only 3.8% of the total area, whereas four wetlands larger than 10 km<sup>2</sup> accounted for 39.6% (107.52 km<sup>2</sup>) of the total area, bimodal size distribution. At the regional scale, Gyeonggi-do and Gangwon Special Self-Governing Province accounted for the largest wetland areas, whereas Seoul Special City and Gyeongsangbuk-do had only limited wetland area coverage. At the municipal level, Gangneung-si, Anseong-si, Jecheon-si, and Chungju-si showed relatively large numbers of wetlands. Large wetland areas were concentrated in Gimpo-si (59.10 km<sup>2</sup>), Hwaseong-si (28.13 km<sup>2</sup>), and Pyeongtaek-si (31.39 km<sup>2</sup>). In Gyeongsangbuk-do, wetlands were recorded only in Bonghwa-gun and Mungyeong-si, which indicated a restricted distribution. The basin also included nine legally designated wetland protected areas, which underscored its conservation significance. These results indicate pronounced spatial heterogeneity across administrative units and provide baseline information for wetland management and policy development.