Objective To support the transformation and development of resource−exhausted cities in Northeast China and scientifically advance the ecological restoration of coal mining subsidence wastelands and comprehensive management of territorial space, this paper takes the Xi'an Coal Mining Area in Liaoyuan City as the research object to carry out ecological suitability assessment of territorial space development, so as to provide a scientific basis for spatial optimization and ecological restoration practices in the mining area.

Methods The analytic hierarchy process (AHP) was adopted to construct an evaluation system consisting of 9 indicators under 3 criterion layers: soil quality, vegetation status and topography, and the indicator weights for three utilization directions (arable land, forest land and grassland) were determined. The exponential sum method was applied to quantitatively calculate the ecological suitability index, and ground subsidence risk was introduced as the limit constraint to revise the evaluation results. On this basis, suitability grading and comprehensive zoning were completed in combination with GIS spatial overlay analysis.

Results The areas suitable for cultivation, forestry, grassland, fishery and wetland ecological landscape restoration in the study area are 6.28 km², 10.06 km², 1.13 km², 0.13 km² and 2.74 km² respectively. The overall spatial pattern features forest−suitable land as the dominant type, concentrated and contiguous arable−suitable land, and differentiated utilization of subsidence water areas. According to the evaluation results, 7 types of territorial space functional zones were delineated, including wetland ecological recreation area, modern agriculture and forestry planting area, and abandoned quarry experience area.

Conclusions The evaluation method coupling the exponential sum method and the limit condition method balances the comprehensive quantitative characterization of multiple indicators and the rigid constraint of geological safety, which is applicable to the ecological suitability assessment of coal mining subsidence areas in Northeast China. The research results can provide reference for spatial governance of similar resource−exhausted mining areas.