基于景观格局因子的居住点可达绿地质量评价

Evaluation of accessible green space quality in residence based on landscape pattern factors

城市绿地对美化城市、改善城市环境质量起着重要作用,科学度量城市人居绿地环境可为城市合理规划提供决策依据。首先利用Google Earth Engine平台进行天津市地物分类,然后利用路网数据建立POI居住点的可达范围,在此基础上采用格网法与因子分析法,综合城市绿地面积、生长状态、景观格局指数等指标,构建居住点可达绿地质量评价模型,最终,在居住点可达范围内应用评价模型,对天津市人居绿地环境质量进行评价。结果表明:经过因子分析,得到的可达绿地面积-生长状态因子、可达绿地形状因子和可达绿地破碎度因子在反映居住点可达绿地质量时具有代表性;中心城区与滨海新区居住点可达范围内植被覆盖度低、形状不规则且分布破碎。环城区越靠近中心城区,居住点可达范围内绿地面积越小、分布越破碎,越靠近远郊区,居住点可达范围内绿地面积越大,形状越规则。远郊区受自然条件的影响,居住点可达范围内植被生长旺盛、分布连贯且形状规则;天津市北部居住点可达绿地质量较好,中部及东南部较差,天津市居住点可达绿地质量从优至劣为:远郊区>环城区>滨海新区>中心城区。研究结果可为生态城市评估和绿地系统监测提供方法基础。

Urban green space(UGS)plays an important role in beautifying the city and improving the quality of urban environment.Scientifically measuring the urban residential green space environment can provide decision-making basis for urban planning.Firstly,the land cover classification of the study area was conducted using Google Earth Engine platform,and then reachable areas of POIs of residential areas were determined by the road network data.Using grid method and factor analysis method,comprehensive area,growth status,landscape metrics and other indicators of UGS to construct the accessible green space quality in residence evaluation model.Finally,the evaluation model was applied within the reachable areas of residential areas to evaluate the UGS in Tianjin,which could reflect the UGS quality of Tianjin.The results show that according to factor analysis,the accessible green space area-growth state factor,accessible green space shape factor and accessible green space fragmentation factor are representative in reflecting the accessible green space quality in residence.In the central city and Binhai New Area,UGS within the reachable areas of residential areas are insufficient,with irregular shape and fragmented distribution.The closer the ring city area is to the central city,the smaller the green space area and the more fragmented the distribution within the reachable range of residential areas.The closer it is to the outer suburbs,the larger the green space area and the more regular the shape within the reachable range of residential areas.On the contrary,in the outer suburbs,vegetation within the reachable areas of residential areas grows vigorously,distributes coherently and has regular shape,which owes to the natural conditions.Accessible green space quality in residence is good in the northern part of Tianjin,while that is poor in the central and southeast parts.Accessible green space in residence in various regions of Tianjin follows the order:Outer suburbs>Ring City>Binhai New District>Central City.Results of this research can provide a methodological basis for eco-city assessment and green space system monitoring.