Assessment of habitat quality and ecological red line in southern Jiangsu Province of eastern China based on land use changes

Objective In the context of rapid urbanization, the assessment and simulation of impact of rapid urbanization on habitat quality can provide suggestions for adjusting ecological red line areas and ecologically sensitive areas, so as to improve territorial spatial planning and strengthen ecological spatial control.

Method In this study, the spatial and temporal evolution of land use changes, habitat quality, and habitat degradation degree in 2000, 2010, and 2020 were assessed using the InVEST model and hotspot analysis in southern Jiangsu Province of eastern China. The PLUS model was used to simulate land use changes from 2020 to 2030 and the InVEST model was used to assess habitat quality according to scenarios.

Result (1) From 2000 to 2020, land use in southern Jiangsu Province underwent significant changes, mainly characterized by the transfer of cultivated land to construction land and waters. The average value of habitat quality showed a decreasing trend. Additionally, a spatial distribution pattern emerged, characterized by high quality in the east and west, and low quality in the middle. The degree of habitat degradation showed a radial structure of “low center-high outside”. (2) Among the three land use simulation scenarios in 2030, the urban expansion scenario showed the largest decrease in cultivated land area. Under the ecological protection scenario, forests and lakes were strictly protected; the expansion of construction land was controlled under the sustainable development scenario. The ranking of mean values of habitat quality was ecological protection scenario > sustainable development scenario > urban expansion scenario. (3) The hotspot analysis revealed that in 2020, habitat quality and habitat degradation in southern Jiangsu Province showed a concentrated distribution at the township scale, with the town centers being the cold spots, hotspots mainly in forests and mountains, and watersheds being the hotspot areas of habitat quality. (4) Habitat quality within the ecological red line area was overall high and relatively stable. In future projections, the ecological protection scenario expanded the mismatch area, and the sustainable development scenario decreased the mismatch area.

Conclusion Rapid urbanization and intense human activities are the main reasons for decline of habitat quality in southern Jiangsu Province and low habitat quality in the part of ecological red line area. Therefore, optimizing the spatial structure of territory and reducing the impact of human activities on sensitive ecological environment areas are of great significance for improving the habitat quality in southern Jiangsu Province of eastern China.