Place names reflect the adaptation of human to environmental changes: taking the Erhai Lake Basin in China as an example

Under the global context of climate change, understanding the adaptation mechanisms of human societies to the environment has become a crucial issue for achieving sustainable development goals. The ecological wisdom embedded in traditional knowledge is increasingly valued for addressing environmental changes. This study takes the Erhai Lake Basin in China, as a case to explore the value of toponyms as carriers of local knowledge in revealing environmental changes and human adaptation strategies. Through a systematic analysis of the toponyms and their spatial distribution patterns related to settlement migration in the study area, the findings reveal three key patterns: 1) All of the geographical location fixed 1209 toponyms in the Erhai Lake Basin form three clusters located in low-altitude, flat, and expansive lakeside areas. Toponyms reflecting human life and production activities account for 55.1% of the total, while those reflecting natural environmental features account for 46.1%. 2) A total of 192 toponyms reflect human settlement migration, accounting for 10.01% of the total toponyms, with cluster areas consistent with the overall toponym distribution. These migration-related toponyms can be categorized into five types based on migration characteristics: Shang 上(upper) - Zhong 中(middle) - Xia 下(lower) prefixed toponyms (39.58%) exhibit a distinct vertical distribution from higher to lower elevations; Da 大(Big) - Xiao 小(small) prefixed toponyms (23.96%) are generally found at relatively higher altitudes; Nan 南(south) - Bei 北(north) (20.83%) and Dong 东(east) - Xi 西(west) (10.42%) prefixed toponyms with over half of these two categories being predominantly located on both sides of river valleys; Xin 新(new) - Jiu 旧(old) prefixed toponyms constitute the smallest proportion at 5.21%. 3) Four specific toponyms explicitly indicate past environmental features, with the highest altitude being ~140 m above the current water level of Erhai Lake, reflecting a period of higher water levels in Erhai Lake. The study confirms that the toponymic patterns in the basin reflect the state of human geography, and migration-related toponyms reflect environmental fluctuations and human adaptation processes. This inspires systematic research using toponyms to reveal strategies for human adaptation to environmental change, providing a new perspective for sustainable development practices under climate change.