Landscape structure and network characteristics of the greenway system in Guangzhou City, South China

摘要

Greenways help to conserve natural areas and improve the quality of life for residents, especially in cities experiencing rapid urbanization. In this study, we evaluated the landscape structure and network characteristics of Guangzhou's greenway system and analyzed the potential effects of natural and socioeconomic factors on the construction of urban greenways. The total length and density of the greenway system in Guangzhou was 1319.3km and 0.18km/km(2), respectively. The greenway density in the urban regions was1.5km/km(2), which met the optimal threshold requirement for an urban greenway system. Guangzhou's greenway system had a total of 609 branches and 366 nodes, more than in Xiamen City (China) and Phoenix (AZ), which indicated a high level of network connectivity. The built-up area (area with residential, commercial, or industrial buildings) and the number of intersections of the transportation network were positively and linearly related (R-2=0.46 and 0.78, respectively) to the length of Guangzhou's greenways in each 1-km(2) pixel grid. Population density (R-2=0.47, p0.001) and gross domestic product per capita (R-2=0.75, p0.001) were positively correlated with the density of Guangzhou's greenways in each district. These results suggested that greenways were well distributed in the urban regions of Guangzhou. The slope was 5 degrees for 82.8% of Guangzhou's greenway system, which made it suitable for walking and biking; 43.7% of the 265 scenic spots were within 400m, and 64.9% within 800m, of the nearest greenway, indicating their high accessibility from greenways. However, nearly 50% (273km) of the waterfront greenways in Guangzhou were adjacent to poor-quality water bodies. The future priority for optimizing Guangzhou's greenways should be the balancing of environmental protection with social and economic development.