Assessing Structural Connectivity of Urban Green Spaces in Metropolitan Hong Kong

Connectivity is a vital element in landscape structure because of its importance in species-landscape interactions. Connectivity analysis of green spaces in urban landscapes, especially in high-density cities such as Hong Kong, differs from that of habitats in natural or rural landscapes. Using the human being as the target species, we formulated with GIS techniques a resistance weight, a structural connectivity index and an ecological barrier effect index to assess connectivity of green spaces. Two factors were included in the modeling, namely the resistance of different land uses related to human activities, and the distance between different urban green spaces. We analyzed the relationships between the connectivity index of green spaces and green cover, elevation, building density and population density. Our results indicate that low connectivity usually occurs in both old and new town centers with high building density and low green cover, and in areas occupied by land uses with a high resistance weight. However, urban density may not necessarily have a negative influence on the structural connectivity of green spaces. Green cover also may not necessarily have positive impact on connectivity if the green spaces have a poor spatial pattern. Adding more green stepping stones, large green spaces and green corridors to form greenways and shortening the distance between urban green spaces can offer a spatial-planning strategy to increase the green space connectivity in Hong Kong. The study provides insights to optimize connectivity of green spaces to improve the urban living environment in high-density metropolises.