Planning a water-constrained ecological restoration pattern to enhance sustainable landscape management in drylands

Ecological restoration is an important approach to improving landscape sustainability. However, ecological restoration in drylands is strongly limited by water resources. Therefore, a technical route for ecological restoration in drylands that creates sustainable landscapes based on those water constraints is needed. In this study, we develop a spatially explicit framework named "Constraint-Pattern-Benefit" to plan ecological restoration patterns in Inner Mongolia, China. Based on a prediction of the ecosystem service (ES) increase under limited evapotranspiration as a water constraint, we constructed 5 landscape sustainability-related strategies with 100 ecological restoration scenarios, which considered fragmentation of restoration locations, distance to city, water consumption, and the allocation scale to determine the spatial arrangement of ecological restoration. Results show that the ES increase potential of ecological restoration under water constraints is distributed in the center of Inner Mongolia. The multi-objective scenario simultaneously achieves 59.1% water yield, 74.2% soil conservation, 57.2% sand fixation, and 52.8% carbon sequestration with 50% restored landscape. Considering the indicators of fragmentation, water consumption, and distance to city decreases the restored landscape fragmentation from 0.44 to 0.26, improves the restoration efficiency by 14.41%, and increases the beneficiary population by 35.5%, respectively. Small-scale allocation can further increase the ES realization efficiency, which is on average 4.8% higher at the city scale than at the provincial scale. Moreover, this approach focuses on the sustainable effect of the spatial arrangement on dryland landscapes at different scales, which provides methodological support for improving the sustainability of drylands.