Evaluation of regional ecological carrying capacity coupling with landscape pattern and ecosystem services

The main basis of landscape development and planning is the evaluation of regional ecological carrying capacity. The results of this evaluation can reflect the extent to which ecological carrying capacity can remain unaffected by continuous development and planning activities of humans. Nowadays, among the existing methods for assessing ecological carrying capacity, the method based on ecosystem services value is relatively mature and widely used. However, the assessment of ecosystem services value is based on the classification of ecological land types in the region; therefore, it is difficult to apply where the land use status lacks extensibility and resilience. To fill this gap, this study coupled landscape pattern and vegetation change parameters with the ecosystem service provision capacity through a comprehensive index system with 3 criteria and 11 indicators. The landscape pattern determined the size, shape, and connectivity of various ecological patches, which in turn affected the abundance, distribution, and population viability and anti-interference ability of the landscape. Thus, landscape pattern indexes could be used to identify regional ecological protection priorities under urbanization, further improving regional environmental quality and resource utilization efficiency. The vegetation change index could spatially describe changes in breadth and depth of vegetation cover in regions, which were the result of the interaction between nature and human activities. This study applied the assessment model to Shijiazhuang City, measuring its comprehensive ecological carrying capacity at the grid, township and district scale. The results showed that the spatial distribution of the ecological carrying capacity of Shijiazhuang based on the grid analysis was relatively high in the western mountainous area and low in the east plain. Regarding the indicator layer, the distribution of ecosystem service provision capacity was relatively consistent with the comprehensive ecological carrying capacity distribution, whereas the landscape metrics presented a mosaic distribution pattern and the vegetation change index represented a circle layer distribution pattern. Meanwhile, the spatial heterogeneity of the first-level indicators was more significant. The further regional analysis results focusing on the administrative scales of districts and townships showed that the indicator distribution on smaller scale was more heterogeneous, and evaluation results in some regions were inconsistent with those assessed at higher administrative level. Therefore, local decision-makers should adjust more targeted management objectives and actions according to the jurisdiction. In general, through horizontal analysis in space and vertical contrast on scales, western Shijiazhuang City should focus on integrating the forest ecosystem conservation into urban development and construction; the eastern districts and townships should coordinate between the ecological environment and economic development, and improve the ecosystem service capacity through the optimization of ecological space patterns, thereby improving the comprehensive carrying capacity of national land space.