Ecological Network Optimization in Highly Urbanized Areas: Achieving Connectivity Between Natural and Human Activity Spaces—A Case Study of Guangzhou

The insufficient connectivity between human activity spaces and the natural environment impairs ecosystem connectivity and leads to the gradual compression of the natural environment by human activity spaces. In highly urbanized areas, human activity spaces and natural environments are often disconnected, yet few existing ecological network studies have actively incorporated human activity spaces into the an optimization framework to promote their integration with natural ecosystems. Taking Guangzhou as a case study, this research integrates MSPA-InVEST (the Morphological Spatial Pattern Analysis—Integrated Valuation of Ecosystem Services and Trade-offs model), landscape connectivity assessment, the MCR model (Minimum Cumulative Resistance model), and the gravity model to identify ecological sources and potential corridors. It innovatively introduces enterprise kernel density to add planned sources and planned corridors, thereby developing an ecological network optimization scheme that achieves spatial integration between human activity spaces and the natural environment. The results identified 38 ecological sources (total area ~2907.65 km2, accounting for 39.07% of the study area) and 46 basic ecological corridors, showing a spatial pattern of “dense in the north, sparse in the central-south”. The addition of 7 planned sources and 22 planned corridors increased the network’s closure, connectivity, and linkage rate by 115.38%, 24.79%, and 23.26%, respectively, with the overall connectivity reaching 0.53. The spatial pattern shifted from an uneven distribution to a “north–south linkage and full coverage” layout. The optimized ecological network effectively connects the major ecological source areas in Guangzhou and, in combination with natural corridors such as rivers, forms a comprehensive ecological security pattern of “mountains–water–forests–city”, thereby constructing a comprehensive ecological network framework for highly urbanized areas. This method takes into account both ecological integrity and economic spatial demands, providing a scientific reference for the construction of ecological networks and the optimization of territorial space in high-density megacities, with the ultimate goal of integrating human activity spaces with natural ecosystems and fostering sustainable development.