Is the resettlement suitability of migrants in arid mountainous areas high or low? A case study of ecological migration in Gansu Province, China

Extreme climate, natural disasters, and deep poverty have triggered increasingly common migration worldwide. China’s resettlement projects have relocated approximately 10 million residents from disaster-prone, drought-prone, mountainous areas to suitable resettlement sites. However, ecological migration (EM) and short-period resettlement site selection may pose potential risks to the sustainable development of resettlement. Furthermore, previous research has focused on immigrants’ livelihoods but paid less attention to resettlement suitability (RS) in arid mountainous areas. This paper conducts a case study investigating the measurement, differences, and obstacles of RS for EM resettlement sites in northwest China’s mountainous regions. We select 29 indicators from five dimensions, including geology, climate, economy, transportation, and public services, to construct an assessment model of RS. The results show that resettlement site suitability is inversely related to altitude and directly related to economic vitality. RS along traffic arteries and near water systems is significantly higher than in other areas. Long-distance resettlement’s average suitability is 14.63% higher than short-distance resettlement, facilitating migration resettlement. Topographic and geological conditions are the primary factors hindering RS in arid mountainous areas, with an obstacle degree of 37.11%. Flat terrain, convenient water access, and medical treatment are crucial for RS. This research offers insights into EM decisions in arid mountainous areas and improving RS and regional sustainable development under global climate change.