A novel framework for assessing and enhancing urban ecological network resilience: integration of key species information and deduction of spatial optimization pattern

Resilience of ecological networks (ENs) is a critical indicator of urban ecosystem stability. However, conventional unweighted ecological network assessments deviate from actual ecological conditions by neglecting the spatial heterogeneity of dispersal resistance. Taking the Urban Agglomeration around Hangzhou Bay (UAHB) as a case study, this study constructs a weighted ecological network by integrating species information and embedding dispersal costs into corridor weights. Building upon this foundation, we propose three ecologically modified resilience indicators: the optimal connected subgraph coefficient (S'), the ecological efficiency index (E'), and the ecological resilience index (ERI). These metrics are utilized to characterize the network's response to dynamic disturbances and to conduct a benchmark comparison of eight spatial synergistic optimization strategies. The findings reveal the following: (1) By internalizing species-specific dispersal costs into the weights, we identified 40, 160, 95, 73, and 65 corridors corresponding to levels 1 through 5, respectively. This approach addresses the limitation of unweighted networks, which often overlook local spatial heterogeneity. (2) Under probabilistic and deterministic attack scenarios, the node removal rates when the ERI drops to 0.1 are 0.6 and 0.3, respectively. These values are lower than those derived from traditional resilience indicators. This indicates that the persistence of structural stability does not imply the persistence of functional integrity. Relying solely on structural metrics may underestimate the true vulnerability of the network to functional loss. (3) Regarding spatial synergistic optimization, utilizing our proposed resilience assessment framework, we identified the quantity-priority strategy from a global perspective (G_no) as the optimal approach. This strategy successfully increases the resilience threshold from 0.23 to 0.4, achieving a growth of approximately 74%. This study advances the transition of resilience assessment from geometric connectivity to functional persistence, providing a scientific basis for cross-regional urban ecological governance.