摘要
道路树冠覆盖(RTC)是城市树冠覆盖(UTC)的最重要组成部分。本文从RTC量变及其与城市扩张的关系出发,构建了RTC量变评价体系,为城市生态规划及道路绿地系统管理提供依据。基于RTC与道路(R)、不透水地表(I)、UTC、潜在UTC(PUTC)变化的量比关系建立了5项评价指数,并以北京市主城区为研究区域分环路区间进行空间分布特征分析及评价。结果表明:2002—2013年间北京市主城区道路树冠覆盖面积增长显著,RTC面积变化指数为2.142,覆盖率从21.62%提高到35.00%;整体RTC增长相对城市不透水地表变化及道路加权变化呈现明显的优势响应特征;整体I响应指数为1.879,R响应指数为1.736;RTC相对整体UTC增长及PUTC面积减少呈微弱的优势响应特征,整体U(UTC)响应指数为1.055,P(PUTC)利用指数为1.06;RTC面积变化指数、I响应指数、R响应指数、P利用指数在由内向外的城市扩张梯度上具有递增趋势;在各环路区域间,U响应指数基本均衡,其余指标具有较明显的差异性;RTC面积变化指数在各环路区域间的差异性最大;RTC面积变化指数与R响应指数的相关性最为显著,越往外围,RTC的面积变化越为显著,其对道路和城市不透水地表变化的响应优势也越为显著;新增道路和不透水地表具有明显更高的RTC覆盖率;U响应指数和RTC的增长率不显著相关;北京主城区RTC环向区间差异性显著,内城提升需求高,特别是2环内区域的滞后性需要引起关注;RTC在整体城市树冠覆盖中的地位和倾向性优势仍待加强,3环内区域尤为迫切;RTC提升空间压缩,建成区不透水地表潜力开发是RTC后续增长的重要途径。
Roadside tree canopy(RTC)is the most important component of urban tree canopy(UTC).In this study,we constructed an evaluation system of RTC quantitative change from a perspective of the relationship between RTC quantitative change and urban expansion,which can provide basis for urban planning and road green space system management.Based on quantitative relationships between RTC and road,impervious surface,UTC and possible UTC(PUTC),we established five evaluation indices.The spatial distribution analysis and evaluation were carried out for regions between ring roads in the main urban area of Beijing.The results showed that the growth of RTC area was remarkable from 2002 to 2013,with a change index of the RTC area being 2.142,and the coverage rate increasing from 21.62%to 35.00%.The overall RTC growth showed obvious dominant response compared with the urban impervious surface change and the road weighting change.The overall I(impervious surface)response index was 1.879,and the R(road)response index was 1.736.The RTC showed weak dominant response compared with the overall growth of UTC and the decrease of potential UTC area,with overall U(UTC)response index of 1.055 and P(possible UTC)utilization index of 1.06.RTC area change index,I response index,R response index,and P utilization index all showed an increasing trend from inside to outside urban expansion.U response index was basically balanced between ring road areas,while the other indices had obvious differences.The difference of RTC area change index was the biggest between ring road areas.R response index showed the most significant correlation with RTC area change index.The RTC area changed greatly in urban outskirts,and its response advantage to road and urban impervious surface changes all showed a more significant trend from the inside to outside.New roads and impervious surfaces had higher RTC coverage.There was no correlation between U response index and RTC growth rate.The difference of RTC between ring roads in the main urban areas of Beijing was significant,with a promoted demand in the inner city,and especially the lagged demand inside the 2 ndring road which needed to be concerned.RTC position and tendency advantage in the overall urban tree canopy cover need to be strengthened,especially in regions inside the 3 rdring road.Leaving room for RTC growth was compressed.Exploring potentials of impervious surface in built-up areas is an important approach to RTC subsequent growth.
作者
张文
李晓婷
马杰
贾宝全
ZHANG Wen;LI Xiao-ting;MA Jie;JIA Bao-quan(Research Institute of Forestry,Chinese Academy of Forestry,Key Laboratory of Tree Breeding and Cultivation,National Forestry and Grassland Administration,Urban Forest Research Center,National Forestry and Grassland Administration,Beijing 100091,China;East China Jiaotong University,Nanchang 330013,China;Henan Institute of Science and Technology,Xinxiang 453003,Henan,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2020年第8期2678-2690,共13页
Chinese Journal of Ecology
基金
林业公益性行业科研专项经费项目(201404301)
北京市自然科学基金项目(8152031)
江西省高校人文社会科学研究项目(YS19103)
江西省教育厅科学技术研究项目(GJJ190336)资助。