道路交通网络对生态空间质量影响效应研究——以长沙市为例

Research on the Effect of Road Traffic Network on Ecological Space Quality:A Case Study of Changsha City

从规模、结构和功能三维层面定量研究道路交通网络演变对生态空间质量的影响,可更全面、更精细地研究生态空间规模、结构和功能之间的相互影响以及累积效应。文章以中部地区典型城市长沙市为例,开展不同道路交通网络密度和等级下生态空间质量的演化效应研究。结果表明:(1)在规模影响方面,道路交通网络及周边建设活动通过直接占用生态用地造成生态空间规模降低。路网密度越高,侵占程度越大;道路等级越低,对生态空间的作用程度越直接。(2)在结构影响方面,道路交通网络通过带动建设用地的扩张造成生态空间破碎化,使其由“大团块”向“小斑块”转变。(3)在功能影响方面,道路交通网络通过降低高生态功能土地规模,造成区域整体生态质量下降。(4)道路交通网络通过不断改变土地利用格局影响生态空间的规模,在累积效应作用下进而对生态空间结构与功能产生影响,导致整体生态空间质量降低。(5)道路交通网络扩展在保证联通地区的基础上,应尽量避让生态空间,优先保护大面积完整生态空间,不可避让时则侵占低功能生态区域。

The impact of road traffic network evolution on ecological spatial quality can be studied quantitatively at the scale,structure and function levels,and the interactions among the ecological spatial scale,structure and function as well as the cumulative effects can be more comprehensively and finely portrayed.This paper takes Changsha,a typical city in central China,as an example,and conducts a study on the evolutionary effects of ecological spatial quality under different road traffic network densities and levels.The results show as follows.(1)In terms of the scale impact,the road traffic network and surrounding construction activities cause a decrease in the scale of ecological space by directly occupying ecological land.The higher the density of the road network,the greater the degree of encroachment;the lower the road grade,the more direct the degree of effect on ecological space.(2)In terms of the structural impact,the road traffic network causes the fragmentation of ecological space through the expansion of construction land,resulting in a shift from“large clusters”to“small patches”.(3)In the functional impact,the road traffic network deteriorates the overall ecological quality of the region by reducing the scale of land with high ecological function.(4)The road traffic network affects the scale of ecological space by constantly changing the land use pattern,which affects the structure and function of ecological space under the cumulative effect,leading to the deterioration in the overall ecological space quality.(5)The road traffic network expansion should avoid the ecological space as much as possible on the basis of ensuring connected areas,give priority to protecting large areas of intact ecological space and encroach on low-functioning ecological areas when unavoidable.