基于“规模—密度—形态”的大连市城市韧性评估

Evaluation of urban resilience of Dalian city based on the perspective of "Size-Density-Morphology"

以建设安全城市为目标,依据地理学和景观生态思想方法,构建基于"规模—密度—形态"的三维城市韧性研究框架,并对2000-2016年大连市各县市区的城市韧性进行评估。其中规模韧性利用生态基础设施工具进行度量,密度韧性利用生态足迹与生态承载力工具进行度量,形态韧性基于源汇景观平均距离指数进行度量。还对各年份三类韧性的组合形式进行综合评判。本文认为,"规模—密度—形态"三位一体的韧性评估方法可有效识别城市的韧性特征,是建立城市规划与城市韧性研究之间有效联系的纽带。研究发现:(1)规模安全是城市空间扩张的基本约束条件;(2)生态承载力是城市密度的安全阈值;(3)"源—汇"景观的空间耦合是优良城市形态的基本特征;(4)是"规模—密度—形态"三个韧性的组合状况而不是某一单项指标决定城市的安全性。基于规模、密度、形态韧性及其组合特征判定,为未来大连的城市发展提出建议:(1)严格限制中心城区与金州区开发强度,遏制其蔓延式增长趋势;(2)严格控制海岸带开发,维持山体和绿色植被斑块的完整性;(3)促进市域均衡开发,提升城市整体韧性;(4)优化新市区开发战略,形成良好城市形态。

Aiming at building a safe city,this study proposed a "Size-Density-Morphology" based three-dimensional urban resilience evaluation framework according to the theories and methods of geography and landscape ecology.By using the framework,the urban resilience of each county in Dalian city during 2000-2016 was evaluated.There are three kinds of urban resilience,namely size resilience,density resilience and morphology resilience.The size resilience could be measured by ecological infrastructure tools;the density resilience could be measured by ecological footprint and ecological carrying capacity;the morphology resilience could be measured by "Source-sink"landscape average distance index.In addition,this paper also analyzed the combining forms of the three types of resilience.This study demonstrates that the three-dimension evaluation framework has a unique capacity to identify the resilience characteristics of city,and it is a key bond which creates the connection of urban planning and urban resilience research.Findings are as follows:(1)The size safety is the primary constraint condition for urban spatial expansion.(2)Ecological carrying capacity is the safe threshold for urban density.(3)The spatial coupling of source and sink landscape is a basic feature of good urban morphology.(4)It is the combination of size-density-morphology resilience to determine the safety of the city rather than each single one.According to the analysis of combination characteristics of the "Size-Density-Morphology"resilience,four suggestions were put forward for the development of Dalian city in future.(1)Strictly limit the development intensity of central urban area and Jinzhou district to curb the urban sprawl trend;(2)Strictly control the development of the coastal zone and maintain the integrity of natural mountain and green vegetation patches;(3)Promote the balanced development on a whole city scale to improve the city's overall resilience;(4)Optimizing the development strategy of new urban area in order to form a good urban morphology.