西部省会城市公共绿地景观格局及其500m半径服务率

Status of pubic green pattern and its 500 m radius service rate in provincial capital cities of Western China

以10个西部省会城市为研究样本,利用GIS图像处理技术对各个城市公共绿地景观格局及其500 m半径服务率、斑块密度、距斑块平均距离等指标进行数据化分析,以揭示各不同规模城市的公共绿地系统结构及其社会服务现状、发展趋势和存在的问题.结果表明:西部省会城市公共绿地系统结构总体合理,服务率水平达到或接近国家标准,但一些大城市中存在公共绿地斑块密度小、分布不均衡和服务功能差的问题;系统结构分析表明城市化进程加剧了公共绿地系统的破碎化程度;相关分析显示公共绿地斑块系统景观连接度、斑块密度及500 m半径服务率之间呈现不同程度的正相关关系,与斑块平均距离呈负相关关系,而与斑块面积无相关性;公共绿地斑块密度、500 m半径服务率和景观连接度与城市规模呈负相关关系.

10 provincial capital cities in western China were taken as study samples and, using the technique of GIS, the landscape metrics such as 500 m radius service rate, patch density, distance were mathematically analyzed to demonstrate the status, tendencies and problems of public green space system in different city scales. The results showed that the qualities in both the public green space pattern and social service of public green space had reached or come near the national standard of landscape cities, but problems such as low patch density, low connectivity and social service level existed in some large cities. The analysis of public green space structure demonstrated that the increasingly urbanized landscape became more diverse and ecologically fragmented. A correlation analysis also indicated that the 500 m radius service rate was positively correlated with landscape connectivity and patch density, and negatively correlated with the mean distance index and did not correlate with the patch area, while the urban scale was significantly positively correlated with the patch density, connectivity and 500 m radius service rate.