Landscape ecological analysis of urban vegetation in Guangzhou,China

The compositions, patches and landscape heteorogentity of Guangzhou urban vegetation are studied by using the principles of landscape ecology in this paper. The results showed that the area of urban vegetation was 26901 4hm 2, and the distribution of vegetation types and regional vegetation coverage were uneven. The patch areas of vegetation were large in scenery vegetation and shelter vegetation, and small in street corner vegetation and small garden vegetation. Most of patches fell in range between 100 and 10000 m 2. Only 1.13% of patches were larger than 1000000 m 2. Structure features of vegetation landscape in old urban areas were small patch, high scattering degree, high diversity, random distribution of vegetation patches and high heterogeneity. In new urban areas, the features were big patches, fine planning, medium landscape heterogeneity. Some suggestions are made according to landscape character of urban vegetation in Guangzhou.

Changing Concepts of City and Urban Planning Practices in Guangzhou(1949–2010): An Approach to Sustainable Urban Development

By focusing on Guangzhou, this paper examines how different concepts of city in terms of urban-rural relationships are shaped in transforming China since 1949, and explores how they influence the way in which urban planning are practiced. In the pre-reform era, the city was defined as a productive space under the system of urban-rural segregation established for securing rapid industrialization. Urban planning was thus only concerned with the development of urban areas. In the 1980 s and 1990 s after the reform, institutional change and economic transformation mobilized the urban-rural linkages. The development of suburban areas was then considered by urban planning, but this consideration was a passive response to urban problems such as population explosion and water resources protection. Since the new millennium, the agenda for sustainable development and problems of uneven urban-rural development have called for the development of urban-rural integration. In this context, the city is conceptualized as a complex of mountain, city, river, farmland and sea, reconstructing the ideology of urban-rural division in defining urban development. Urban planning has therefore sought in an active way to develop a sustainable city embracing rural and natural elements, and to balance economic growth and environmental protection. It is argued that developing the concept of city as a complex of urban and rural elements contributes to the urban planning for sustainable urban development, while this conceptualization relies on the recognition of the integrated urban-rural relationship.

Roles of urban vegetation on balance of carbon and oxygen in Guangzhou, China

The plant biomass and net primary production(NPP) of urban vegetation in Guangzhou were estimated by dimension analysis, tree truck volume, and harvest methods as well as relationship between biomass and NPP and so on. The biomass and NPP were respectively 2875150t and 1058122 t/a. They were respectively 392495t and 64948 t/a in the built-up area and 2482655t and 993147 t/a in the unbuilt-up area. It would make plant biomass, especially NPP decline obviously, if the unbuilt-up area were changed to the built-up area. The carbon content of plant was 1328649 for the total and 13.78 t/hm 2 for the mean, and amounts of carbon fixed and oxygen made by urban vegetation were respectively 4.80 t/(hm 2·a) and 12.79 t/(hm 2·a) for the mean and 462624 t/a and 1232430 t/a for the total, which were equal to 1.45 times and 1.04 times of those by human breathing. However, they were only equal to 7.61% and 4.97% of amount of carbon released and oxygen consumption in urban Guangzhou. The biomass and NPP of urban vegetation in Guangzhou only corresponded to 7.8% and 47.3% of those of southern subtropical evergreen broad-leaf forest in Dinghu Mountain. Therefore, the roles of Guangzhou urban vegetation in balance of carbon and oxygen would be increased greatly if it could be conserved and improved in some way.

Comparisons of urban-related warming for Shenzhen and Guangzhou

本文利用基于卫星遥感资料反映过去几十年中国、尤其是三大城市群区(京津冀、长三角和珠三角)城市下垫面扩张的土地利用数据,开展高分辨率的嵌套数值试验,定量评估并比较了珠三角城市群区广州/深圳城市下垫面扩张对增暖的贡献。广州/深圳大尺度气候背景场类似,城市化对城市下垫面区域增暖贡献接近(35%/44%),但对整个城市区的增暖贡献差别明显(17%/35%)。城市下垫面扩张对最高和最低气温的影响都表现为增温趋势,但最低气温增加趋势更加显著,日较差表现为减小的趋势。

ANALYSIS OF THE IMPACT OF URBAN GROWTH ON THE TEMPERATURE FIELD IN GUANGZHOU

Based on the 1973 – 2003 temperature data of Guangzhou meteorological station and 1980 –2000 temperature data of Foshan airport, the variations of urbanization effect on temperature of Pearl RiverDelta (PRD) and Guangzhou city were analyzed. It was found that the temperature has increased significantlydue to the PRD’s urbanization. During the last 20 years, Foshan airport’s temperature has increased by 0.7°C,and the Guangzhou city’s temperature increased by about 1.1°C during last 30 years. The heat island ofGuangzhou city is obvious but has some differences from other big Chinese cities.

SUSTAINABLE URBAN-RURAL RELATION IN RAPID URBANIZATION AREAS——Case of Transformation of "Urban Village" in Guangzhou

Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. However, most of these studies started mainly from the standpoint of the city government, drumming for the landscape-oriented urbanization, namely pulling-down the urban village and constructing the splendid residence or business buildings. The article maintains that the most important thing the city government should do is to pay much attention to the sustainable living of urban villagers, who would lose their main income source, namely, the collective dividend and the family housing rent. The single method of compensation has been proved to be harmful to the villagers’ community, in which some young villagers relying on rent were no longer to do anything but stay at home. On the other hand, considering the floating population has become the main stream of renters in urban villages, the emergence of urban villages was inevitable and would continue to exist in a long time under the socio-economic transition in urban China and globalization. Based on the analysis above, the transformation of urban village should take more concerns on the housing demands of floating population besides compensation for local villagers. Meanwhile, it is necessary to avoid the "landscape-oriented urbanization" without the "peasant-to-citizen" transformation.

AN APPROACH TO RETAIL COMMERCE LOCATION OF GUANGZHOU URBAN AREA

Proceeding from the commercial function of Guangzhou urban area, this paper expounds the principles and requirements for choosing commercial location, puts forward the bases to determine the limits of commercial centres. Thirty major commercial centres, in Guangzhou urban area are classified by means of cluster analysis. The function, size, hierarchy and interconnection of commercial centres of different groups are studied. The paper emphatically analyzes the major characteristics and formation factors of the commercial location of Guangzhou urban area. Finally, to counter some problems in existence, some suggestions are put forward in order to improve the commercial location of Guangzhou urban area.

STUDY ON THE URBAN TRANSPORT AND LAND-USE OF GUANGZHOU

Changes in transport are likely to preduce changes in land use, and these long-term effects of transport policy may be of considerable potential importance. There is a growing movement, "The New Urbanism", which seeks to reconnect transport with land use and in particular to eslablish transitoriented development where higher-density,mixed-use areas are built around high-quality transit systems. Based on analysis on development and Pattern of urban transport inGuangzhou, this paper researches composition of urban transportation and struclure of travel pattern. The urban transport system development and change in urban form as well as change in land use are closely related. The urban transport, system required and promnoted by the high-density land-use pattern. There are many problems in the urban transportation and land-use, one of the resolving is integration of urban transport planning and land-use planning.

The Impacts of Urban Land Use on Urban Transport System in High-Densely Developed City-a Case Study of Guangzhou

Recently the study on the mutual relationship between urban transport and land use has been one of the hot subjects in the fields of urban geography, urban transport planning and urban planning. This paper tires to carry out some methods, such as multi-analysis statistics method, to specify the impacts of urban land use on urban transport system. Firstly, the choice of urban transport road network affected by the characters of urban land use layout is discussed. Secondly, the promotion of urban public transportation affected by high-density concentrated land use pattern is demonstrated. Thirdly, the impacts of urban city-size on transport system structure characters are expatiated. Finally, the impacts of urban master planning in Guangzhou on the layout of transport system are illustrated.

A study of urban traffic based on the temporal maps:the case of Guangzhou City

Temporal map is an isochronal map taking time as a measuring unit. It traces out the isochrones according to the discrepancy of the time distance between the different sites from the outside of the city and the down town. It can be clear and intuitional to show the different temporal relationships between the outside of the city and the city centre with the temporal map. The problem of traffi c congestion, with its potential for urban chaos, has increased dramatically with a growing number of vehicles and the continuing aerial expansion of Guangzhou. Both transit rid-ers and drivers f ind it is a great diffi culty to try to acquire the necessary information from urban spatial movements. Valuable time is lost due to the absence of good transportation information. So, the paper analyzes a case in Guang-zhou communication with Geographic Information System (GIS), and uses the most popular vehicles, including buses and taxis that are used to measure the temporal distance in the city, and then proposes the design of a new map that better re? ects the status of urban communication, and attempts to change the relationship between one point and another point of travel, reducing the amount of time allocated to such, often complex, movements. This paper also points out the obstacles associated with Guangzhou's existing traff ic congestion, and puts forward a strategy aimed at better def ining the need of linking the temporal map to spatial map of Guangzhou.

Spatial Pattern of Housing Sales Vacancy in Guangzhou’s Urban District, China

Housing vacancy can reflect the destocking degree of the real estate market.Based on the data of 57 opened residential quarters(46,622 units)from 2015 to 2018,this paper constructs a calculation formula of the sales vacancy rate and then analyzes the spatial pattern in Guangzhou’s urban district.The results show that there is obvious differentiation in the spatial pattern of housing sales vacancy in Guangzhou’s urban district,showing a higher spatial pattern in the old area and urban district and a lower spatial pattern in the core area.Subdistricts with high vacancy rates are mainly located in the east of the old area,the south and east of the urban district and near Baiyun Mountain in the north.

基于“城市针灸”方法的存量公房活化模式研究——以广州市为例

在存量时代发展要求下,公房的管理使用成为广州实施城市更新过程中必须面对的挑战。文章回顾了国内外公房更新改造实践经验和“城市针灸”研究进展,结合广州实际情况选取老城区6个较具代表性的公房集聚区开展田野调查与深度访谈,探讨存量公房如何实现有效活化利用的更新难题。结果表明:1)公房对租户的住房保障作用至关重要,尽管面临诸多现实困难,租户仍表现出强烈的社区归属感和邻里信任感,且认可公房的使用价值。2)在系统总结了翻新出售、功能转换和民生保障3种活化模式的基础上,提出广州的公房活化利用“以民生保障为主,其次是功能转换,最后才是翻新出售”。3)在实证基础上,文章回归关注“城市的人”,在人本主义视角、地理学范畴内进一步总结提炼基于“城市针灸”方法的存量公房活化模式分析框架,提出存量公房分类评价综合评估模型,用于判别公房的活化模式类型,并探讨了活化利用实施路径的4个步骤:查找问题,精准诊断;以人为本,点出“穴位”;“穴位”活化,以点带面;良性互动,循环渐进。

基于多源数据的城市活力分布特征及空间治理策略——以广州中心城区为例

提升城市活力的空间治理是推进国家治理体系和治理能力现代化的重要内容。以广州中心城区为例,构建“人群—环境”城市活力模型,运用多源数据测度城市活力系统中人群与环境活力的协调程度。研究发现,广州中心城区正面临边缘地段城市活力较低且功能组成较为单一、城市“人群—环境”活力耦合协调度有待提升的问题。基于此,从公共空间营造、边缘地段产业空间活化、完善多层级治理渠道、促进公众参与四个维度针对性地提出面向活力全球城市的广州城市空间治理策略,为建设和提升活力广州提供思路,也为粤港澳大湾区各城市的空间治理提供实践参考。

广州城区垂直绿化景观应用现状调查

以广州城区五大片区主要的公园、广场、商场以及其他典型公共区域的垂直绿化景观为主展开应用现状调查,调查发现,广州城区经济新区、行政中心区垂直绿化景观优势明显,不同年龄人群对不同区域垂直绿化景观偏好度、满意度不同。最后针对存在的问题提出建议:传承岭南园林特色,促进垂直绿化景观制度化,加大宣传,加强管理。

物联网技术支持下的城市热环境时空变化分析

热环境是城市生态系统最为关键的大气环境要素之一,开展城市热环境研究的前提是在时空维度上获取足量的热环境参数。利用先进的物联网技术构建了在线式热环境监测设备,收集2022年10月16日至24日广州大学校园气温、风速、太阳辐射和地面温度四种热环境参数,分析小尺度下城市热环境的时空变化特征。研究结果表明:1)不同测点之间的风速特征具有一定的相关性,极个别测点的风速特征与其它测点相关性仅在0.5左右,显示其小气候的独特性;2)不同测点风速和热岛强度变化时空差异明显,即使距离靠近的测点,受邻近建筑和植被特征的影响热环境特征会有所差异,各测点的日间风速大,热岛强度较为明显,夜间风速较小,热岛强度较弱;3)地面温度与气温的相关性达0.8左右,这种相关性在夜间表现更为密切,并且这种关系受风速的影响不大。研究结果反映了城市热环境参数在小尺度上的高度异质性,并揭示了物联网技术在城市热环境监测领域的可行性、便捷性和高效性。

企业更替耦合土地发展的城市更新策略——以广州海丝城为例

基于企业发展与土地整备来推动城市空间有效更新是重要的实践和学术议题。研究基于“问题—对策”的分析框架,以广州海丝城为研究范围,利用ArcGIS和营商主体大数据分析技术,对企业更替状况、行业发展趋势和土地资源配置进行量化分析。研究发现:区域内在业企业年龄结构较年轻,但整体企业生命周期与土地供地期限不匹配;诸如数字经济试验区和开发区等政策型区域的企业迭代趋势显著;总部经济的集聚对区域发展产生多重外溢效应;用地空间破碎和国有集体权属混杂使城市更新的难度加剧。基于企业和土地数据的分析模型,提出基于企业生命周期灵活化土地出让、构建总部生态圈、鼓励土地混合利用和建立差异化土地供应机制等城市临港区域更新策略。

城市外围地区农村物流设施空间分布演变及影响因素--以广州市为例

城市外围地区农村物流设施是保障城乡物资双向流通和农村产业发展的重要支撑。以广东省广州市为例,综合使用多源空间数据和空间回归模型等分析方法,探索城市外围地区农村物流设施空间分布演变特征及影响因素。在空间分布演变方面,城市外围地区农村物流设施从单核转向多核,具有圈层化、等级化特征,与广州市空间发展方向和空间格局相一致,最外围地区物流设施建设短板突出;受村级设施分布变化影响,物流设施集聚性呈现“增强—减弱—增强”的波动。影响因素方面,人口因素、交通因素和工业因素对物流设施分布有显著正向影响,农业因素对其有显著负向影响,区位因素对其无明显影响。研究结果能够丰富对农村物流设施分布演变规律的认识,为城市尺度的农村物流设施的布局优化和支撑要素的建设等提供参考。

认知众包模式下的总体城市意象特色分析方法与广州市实践

引入“认知众包”这一概念,以社交媒体数据为信息抓手,以广州市为分析对象,逐级阐释“理论探析—信息提炼—转译分析”的意象特色解析流程:通过意象特色属性与社媒数据的特征拟合,构建场景特色与攻略特色结合的数字化总体城市意象特色体系;以可意象性数字量化为技术主轴,提出众包型意象特色的信息提炼框架,搭建从网络素材到认知信息再到意象要素的提炼途径;将要素频次作为统计归纳的基础,从强度、等级、空间分布等方面对意象特色进行整合剖析,得到广州市三能级交互的意象特色体系。同时,捕捉到意象特色在新方法的促进下形成的变化模式、创新动力和问题体现等情况,构建一个非介入式的公众认可的广州城市特色体系,实现可读、可看、可感知的意象分析再创新。

基于改进浮动单元的城市职住平衡时间尺度估计——以广州市为例

已有研究对城市职住平衡的测度往往存在可塑性面积单元问题,且忽略了交通网络在职住联系中的媒介作用。提出一种改进的浮动单元法,构建基于道路和城市轨道交通网络的数据集,以时间为职住分析尺度生成浮动单元,运用手机信令数据对职住平衡进行测度。以广州市为例,对就业中心和居住区的职住平衡时间尺度进行估计。研究发现:广州市中心城区职住平衡时间尺度分布呈圈层式空间特征,职住平衡时间尺度从一级就业中心向外围先减小再增大;城市轨道交通缩小了就业中心的职住平衡时间尺度;一级、二级(不处于一级就业中心的辐射范围内)和三级就业中心的职住平衡时间尺度分别为32~40 min、14~28 min和10~20 min,而居住组团的职住平衡时间尺度主要依附于就业中心且受到城市轨道交通的影响。最后,提出在合适的时间尺度下对职住空间结构进行评估和优化住房和就业等资源配置,并重视城市轨道交通对职住空间结构的影响。