With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators...With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators and planners to optimize the urban development areas and define the ecological protection red lines. Based on the SPOT images and field investigation data of urban green spaces within the sixth ring road of Beijing in 2000, 2005 and 2010, the study investigated the dynamic changes of urban green spaces in this area, by means of GIS techniques and landscape ecology methods. The results indicated that green spaces in Beijing have decreased by 207 km2 from 2000 to 2010 at the expense of agricultural lands and waters. Although there has been some increases in urban forests and grasslands, it cannot compensate the rapid decrease of urban green spaces. The land cover types conversion occurred mainly in the areas between the fifth and sixth ring roads while the zones encircled by the fourth ring road had a little change. In addition, landscape metrics such as number of patches(NP) and shape index(SHAPE) increased, but the mean nearest-neighbor distance(MNN), aggregation index(AI) and patch cohesion index(COHESION) decreased during the period of 2000-2010. Also green landscapes became considerably isolated and fragmented. The study disclosed the obvious changes of green space size, composition and layout in urban districts of Beijing City from 2000 to 2010, and highlighted that construction of urban green space should consider not only the geometric or aesthetic effect, but also the increase of vertical green volume and optimization of spatial layout to fully develop the ecological service functions of green spaces.展开更多
大量的研究表明,城市绿地能有效地缓解热岛效应。文章通过Web of Science检索相关文献,综述城市绿地空间格局对热岛效应的影响研究。总结了目前这一领域的研究重点,并对主要的研究方法和结果进行梳理,讨论现有研究存在的问题与不足,提...大量的研究表明,城市绿地能有效地缓解热岛效应。文章通过Web of Science检索相关文献,综述城市绿地空间格局对热岛效应的影响研究。总结了目前这一领域的研究重点,并对主要的研究方法和结果进行梳理,讨论现有研究存在的问题与不足,提出相应的改进意见和未来研究方向。目前该研究主要集中于对城市绿地格局与热岛效应之间的关系,以及由此带来的社会、环境、健康等问题。主要的研究方法是对遥感影像中的城市绿地进行提取,借助景观指数对城市绿地格局进行量化,同时通过遥感卫星数据对城市地表温度进行反演,计算城市热岛效应的强度,进而分析城市绿地格局与热岛效应之间的相关性。通过不同文献分析发现相关性结果存在一定的矛盾。未来的研究一方面需要不断完善城市绿地、城市热岛效应的测度方法,另一方面,需要从实践与战略的层面思考科学问题与规划建设问题的结合。展开更多
基金Sponsored by Study on Space-time Rules of Beijing Urban Green Space Ecosystem Regulating Rainwater Runoff and Control Countermeasures(31200531)
文摘With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators and planners to optimize the urban development areas and define the ecological protection red lines. Based on the SPOT images and field investigation data of urban green spaces within the sixth ring road of Beijing in 2000, 2005 and 2010, the study investigated the dynamic changes of urban green spaces in this area, by means of GIS techniques and landscape ecology methods. The results indicated that green spaces in Beijing have decreased by 207 km2 from 2000 to 2010 at the expense of agricultural lands and waters. Although there has been some increases in urban forests and grasslands, it cannot compensate the rapid decrease of urban green spaces. The land cover types conversion occurred mainly in the areas between the fifth and sixth ring roads while the zones encircled by the fourth ring road had a little change. In addition, landscape metrics such as number of patches(NP) and shape index(SHAPE) increased, but the mean nearest-neighbor distance(MNN), aggregation index(AI) and patch cohesion index(COHESION) decreased during the period of 2000-2010. Also green landscapes became considerably isolated and fragmented. The study disclosed the obvious changes of green space size, composition and layout in urban districts of Beijing City from 2000 to 2010, and highlighted that construction of urban green space should consider not only the geometric or aesthetic effect, but also the increase of vertical green volume and optimization of spatial layout to fully develop the ecological service functions of green spaces.
文摘大量的研究表明,城市绿地能有效地缓解热岛效应。文章通过Web of Science检索相关文献,综述城市绿地空间格局对热岛效应的影响研究。总结了目前这一领域的研究重点,并对主要的研究方法和结果进行梳理,讨论现有研究存在的问题与不足,提出相应的改进意见和未来研究方向。目前该研究主要集中于对城市绿地格局与热岛效应之间的关系,以及由此带来的社会、环境、健康等问题。主要的研究方法是对遥感影像中的城市绿地进行提取,借助景观指数对城市绿地格局进行量化,同时通过遥感卫星数据对城市地表温度进行反演,计算城市热岛效应的强度,进而分析城市绿地格局与热岛效应之间的相关性。通过不同文献分析发现相关性结果存在一定的矛盾。未来的研究一方面需要不断完善城市绿地、城市热岛效应的测度方法,另一方面,需要从实践与战略的层面思考科学问题与规划建设问题的结合。
