两岸典型城市生态功能网络的组成与结构

城市景观的发展加速了景观结构的更新,亦使得景观功能日趋完备;同时,由于城市化亦衍生了景观破碎化以及城市热岛效应等一系列限制当前城市发展的环境问题。因此,城市景观优化必须在充分考虑经济和生态双重需求的前提下,寻求与自然生态体系协调的生态问题解决途径。本文通过对城市生态网络组成与结构的现状分析,阐明城市生态系统间的空间关系,以网络结构的优化达到保护生态环境,提高城市整体开放空间价值的目标。选择经济发展稳定且生态环境良好的中国台湾乌溪流域(台中地区)及深圳市为研究区,通过耗费距离模型评价两岸典型城市生态网络结构。结果表明:两地城市生态功能网络均受城市发展影响,生态中心与社会经济中心的空间位置出现显著的两极化,且生态功能中心与联系中心并不吻合,使得生态功能的流动与传输更依赖于城市范围内的生态组分与结构通达性。因此,为提升城市生态功能,需从强化生态功能网络结构入手,整合城市内的生态景观单元,提高关键生态节点的通达性,进而优化城市景观生态。

Elements and configuration of ecological function network in typical cities of the Mainland and Taiwan

Rapid urbanization accelerates the evolvement of urban landscape through urban function upgrading and spatial configuration renewing. However, the consequent eco-environmental problems, such as landscape fragmentation and heat island effect, have negative effects on the development of urban landscape. Therefore, the spatial optimization of urban landscape should take the economic and ecological needs into account, and propose ecological approaches for solving eco-environmental problems. Through analyzing the present status of the elements and configuration of urban ecosystem, the relationships among the elements were illuminated, aimed to protect the environment and promote the open spatial value of cities through optimizing urban framework. Taking Shenzhen of the Mainland and Wuxi of Taiwan, the two cities with stable economic development and well environment as study cases, their ecological function networks were evaluated by cost distance model, and the results showed that the urban ecological function networks in Shenzhen and Wuxi were significantly affected by urban development, with the location of their ecological center and economic center polarized obviously. The ecological center was far away from the transmission center, and the ecological functions flow and transmission had to depend more on the ecological components and unblocked structure within the areas of the cities. It was suggested that urban framework should be strengthened to promote urban ecological function, with the landscape units optimized and the key network nodes unblocked, which in turn could optimize urban landscape.