城市生态系统指标相互影响的定量研究

应用网络理论对城市生态系统进行了分析,并通过网络模型分析了城市生态系统中各因子之间的关系.对城市生态系统中3个子系统所含指标的相关关系及指标之间的权重进行确定,依此建立城市生态网,并利用复杂网络理论对城市生态网进行了研究,结果如下:1)城市生态网是以城市生态系统指标为节点,以带权有向边将其连接,构成的相互交错的网状结构;2)二、三线城市生态网的网络平均Bacon数分别为2.76和2.62,城市生态网可能是一个小世界网络;3)在城市生态网中,最短路径选择时应遵循最能满足实际问题需求的原则;4)二线城市生态网关键节点是第三产业占GDP比例,三线城市生态网关键节点是工业SO2排放量.本文为整体研究城市生态系统提供了参考.

Quantitative study of indicator interactions in urban ecological system

The purposes are to analyze the urban ecosystem with the network theory,establish a network model for urban ecosystem,give the definition of the urban ecology network,and explore the relationship among factors in the urban ecosystem through the network model.The relationship and the weight among indicators of three subsystems of the urban system have been discussed and determined through the analysis.With these relationships and the weights,the urban ecology networks were established,and then the networks were studied with complex network theory.The results suggested that: 1) the urban ecology network was a net structure constituted by indicators of urban ecosystem and the indicators were connected by the directed edges weight;2) The network average bacon numbers were 2.76 and 2.62 respectively of large cities and small and medium-sized cities,which indicated the urban ecology network might be a small world network;3) In the urban ecology network,when the shortest path was selected,the principle that,instead of considering the smallest weight,to meet the actual requirement was the prime consideration should followed;4) In the urban ecology network,the key node could be determined by the importance of the node.The proportion in GDP of the tertiary industry was the key word in the large cities,and industrial SO2 emission was the key word in the small and medium-sized cities.