Enhancing Ecological Network Connectivity Through Urban–Rural Gradient Zoning Optimization of Ecological Process Flow

Urbanization has significantly impacted ecological connectivity, making the optimization of ecological networks (ENs) crucial. However, many existing strategies focus on overall network structure and overlook the spatial concentration of local ecological processes flow (EPF), limiting the effectiveness of ecological planning. This study proposes a novel EN optimization framework based on urban–rural gradient spatial zoning to enhance connectivity from the perspective of EPF. The framework divides areas outside the core urban zone (CUZ) into the urban fringe zone (UFZ), urban–rural interface zone (UIZ), and natural rural zone (NRZ), applying tailored optimization strategies in each zone. These strategies include increasing corridor redundancy, reducing corridor resistance, and expanding corridor width to alleviate EPF concentration. Using Jinan, a mega-city in China’s Yellow River Basin, as a case study, this study simulated EN changes over 20 years and validated the framework’s effectiveness. Optimization validation showed that increasing ecological land in low-flow corridors to 65% in the UIZ and expanding NRZ corridors to 5 km improved connectivity by 6.3%, addressing seven pinch points and three barrier points. This study highlights the importance of optimizing ENs via urban–rural zoning to support sustainable development and ecological protection policies.