Sustainable Development Mode Based on Ecological Conservation in the Transition Zone Between Cold and Arid Regions

The Qilian Mountains (QLMs), a critical transitional zone between China’s cold and arid regions, serve as a vital ecological security barrier and water conservation area. Their sustainable development is essential for achieving regional ecological civilization and coordinated socio-economic progress. This study, grounded in ecological carrying capacity theory, established a comprehensive evaluation index system for the QLMs, delineated ecological functional zones using natural and socioeconomic data from 2001–2020, and then explored six sustainable development modes. Results revealed significant spatial heterogeneity in ecological carrying capacity, based on which ecological red line (32.02%), yellow line (40.30%), and green line (27.68%) zones were designated. For different zones, six differentiated development modes were proposed, the ecological conservation mode emphasized strict protection and systematic restoration to secure key ecological functions. The ecological compensation mode used institutionalized compensation to offset conservation costs and improve both protection performance and livelihoods. The ecological tourism mode leveraged natural and cultural resources to generate green income. The aboriginal integration mode strengthened resilience through livelihood transition and cultural continuity. The community co-management mode enhanced local governance through shared rights, responsibilities, and benefits. The social participation mode reinforced regional governance via multi-actor collaboration and resource integration. Overall, red line zones emphasized conservation and compensation, yellow line zones balanced social participation, while green line zones integrated all six modes. This study provided actionable solutions to resolve the conflict between ecological protection and economic development in the QLMs, and offered a replicable ‘assessment-zoning-modeling’ framework for sustainable development in other ecologically fragile and barrier regions in China.