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1.
China is experiencing a process of rapid industrialization and urbanization at the cost of agricultural land and environment,particularly in the costal areas. This study takes Jinan as a case presenting a time-series analysis of urban land expansion from 313 to 2003. The results show that the urban expansion of Jinan city mainly took place in the last 100 years, especially after the economic reform in 1978. Social development and economic growth,urban population growth and migration policies were factors driving the urban land expansion. Urban sprawl resulted in a disappearance of wetlands and a great loss of agricultural land, and over-pumping of ground water that led to disappearance of the city‘s feature,namely “the city of springs“.  相似文献   

2.
In recent years flows of foreign direct investment (FDI) to developing countries have rapidly been increasing. It is now an important contributor to the national economy and urban growth in scores of developing countries. Rapid urbanization in these countries is leading to many problems in the cities. Existing urban infrastructure and municipal services have been unable to cope with the increased demand arising from growing population and rapid economic growth. Consequently, the environment in these cities has deteriorated alarmingly. This paper assesses the role of FDI in urban environmental management (UEM) by analyzing the linkages between them for Hanoi City in Vietnam. The paper's analysis and findings are presented under three main themes: one, FDI, employment and income; two, FDI and environmental degradation; and three, potential of utilizing FDI for the provision of urban environmental infrastructure and services (UEI&S) in order to improve the urban environment. Both primary and secondary source data have been used. Policy implications of the research findings are drawn from the perspective of sustainable development.  相似文献   

3.
长江流域经济发达地区城市发展思路   总被引:8,自引:2,他引:6  
长江流域具有优越的区位条件和良好的经济基础,改革开放后城市化水平大幅提高,目前该流域的城市格局正处于由传统的封闭型工业生产城市向经济型、开放型和以第三产业为主转变,单体城市也开始向相互依托、相互发展的城市群体转变。本文分析和总结了长江流域城市发展的现状和存在的问题,如城市化滞后于工业化、城市规划同城市发展不相适应、城市建设资金就足和城市生态环境问题等。在此基础上重点对长江中下游地区城市21世纪发展  相似文献   

4.
Abstract

China is experiencing a process of rapid industrialization and urbanization at the cost of agricultural land and environment, particularly in the costal areas. This study takes Jinan as a case presenting a time-series analysis of urban land expansion from 313 to 2003. The results show that the urban expansion of Jinan city mainly took place in the last 100 years, especially after the economic reform in 1978. Social development and economic growth, urban population growth and migration policies were factors driving the urban land expansion. Urban sprawl resulted in a disappearance of wetlands and a great loss of agricultural land, and over-pumping of ground water that led to disappearance of the city's feature, namely “the city of springs”.  相似文献   

5.
生态文明城市是新型城镇化建设的目标,是实现经济发展、民生改善与生态保护协调统一的最佳方式。适度的人口容量、科学的城市规划和有效的城市治理是避免和减轻城市病的根本途径。本文从生态经济学和系统工程学跨学科的视角出发,构建了一个基于适度人口容量,人口流动和城乡均衡发展的生态文明城市建设路径的理论分析框架,并以广东省惠州市为例,根据土地功能定位和主体功能区定位,分别测算了惠州市的适度人口容量;基于人口自然变动和人口机械变动的趋势,预测了惠州市未来人口发展状况。研究发现,惠州市常住人口已略微超过基于土地功能定位测算的适度人口容量,但基于主体功能定位的人口密度模型测算表明,惠州市未来人口发展规模远低于适度人口容量,进而从总体上剖析了惠州市生态文明城市建设中适度人口容量和人口均衡发展方面带有普遍性的问题和原因。由此,揭示出生态文明城市的创建,必须基于人口承载力,走动态规划调控路子,协同推进经济建设、民生改善、生态保护、环境优化和制度改革,真正地促进流动人口市民化、城乡公共服务均等化和社会保障公平化。  相似文献   

6.
Since China’s economic reform in 1978, the cities of China have experienced rapid expansion and urbanization, thereby profoundly transforming the spatial pattern of urban land use in the karst regions, particularly in the urban mountainous area within city, and urbanization has had and continues to have a negative impact on urban mountain area in cities of China. With the rapid development of urbanization and civilization in these regions, environmental degradation has been increasingly serious, especially in the urban karst mountain area, thereby resulting in the destruction and breakage of urban hills that induce serious natural hazard, i.e., flood hazard.  相似文献   

7.
Cities play a prominent role in our economic development as more than 80 % of the gross world product (GWP) comes from cities. Only 600 urban areas with just 20 % of the world population generate 60 % of the GWP. Rapid urbanization, climate change, inadequate maintenance of water and wastewater infrastructures and poor solid waste management may lead to flooding, water scarcity, water pollution, adverse health effects and rehabilitation costs that may overwhelm the resilience of cities. These megatrends pose urgent challenges in cities as the cost of inaction is high. We present an overview about population growth, urbanization, water, waste, climate change, water governance and transitions. Against this background, we discuss the categorization of cities based on our baseline assessments, i.e. our City Blueprint research on 45 municipalities and regions predominantly in Europe. With this bias towards Europe in mind, the challenges can be discussed globally by clustering cities into distinct categories of sustainability and by providing additional data and information from global regions. We distinguish five categories of sustainability: (1) cities lacking basic water services, (2) wasteful cities, (3) water-efficient cities, (4) resource-efficient and adaptive cities and (5) water-wise cities. Many cities in Western Europe belong to categories 3 and 4. Some cities in Eastern Europe and the few cities we have assessed in Latin America, Asia and Africa can be categorized as cities lacking basic water services. Lack of water infrastructures or obsolete infrastructures, solid waste management and climate adaptation are priorities. It is concluded that cities require a long-term framing of their sectoral challenges into a proactive and coherent Urban Agenda to maximize the co-benefits of adaptation and to minimize the cost. Furthermore, regional platforms of cities are needed to enhance city-to-city learning and to improve governance capacities necessary to accelerate effective and efficient transitions towards water-wise cities. These learning alliances are needed as the time window to solve the global water governance crisis is narrow and rapidly closing. The water sector can play an important role but needs to reframe and refocus radically.  相似文献   

8.
中国城镇化道路的反思与对策   总被引:1,自引:0,他引:1  
改革开放加速了我国的城镇化进程。从1978年至2010年,城镇化率由17.92%迅速提高到49.95%,形成了长三角、珠三角、京津冀三大城市群,一批区域性城市群正在加速形成。城镇化的快速发展特别是城市群的形成为推动我国经济社会发展和增强国际竞争力发挥了重要作用。但与此同时,城镇化也带来了突出的可持续发展问题。主要表现在:人口过度膨胀,城市病集中爆发,经济增长与宜居性背道而驰;城市面貌千篇一律,野蛮拆迁横行,土地型资本运作难以持续;进城易,定居难,城乡"二元社会"问题正演变为城市内定居群体与流动群体"二元社会"问题;城市间恶性竞争,产业同构,建立分工协作的机制任重道远。基于此,本文提出了未来10年推进我国城镇化的对策思路:坚持积极发展小城市和小城镇方针,缓解地域中心城市人口压力;创新农村居民点用地管理制度,实现城镇化与新农村建设有机统一;加强城市规划与管理的科学化,全力提升城市品位;建立跨区域城市协调机制,破解恶性竞争与产业同构困局;促进公共服务均等化,消除新老"二元社会"问题。  相似文献   

9.
量化识别城市扩张在不同发展阶段的时空特征,有助于从宏观上认知城市扩张态势,理解城市化的生态响应。以Landsat TM/OLI影像为数据源,分析了近30a(1986~2016年)长江经济带3个省级城市和4个地级市的城市扩张,包括建设用地的时空变化和扩张模式,以及扩张的生态效应。结果表明:(1)建设用地扩张量在过去30a呈线性递增过程,平均扩张速率在2006~2016年降低,表明建设用地由增量扩张向存量开发转型,但地级市的转型滞后于省级城市;(2)蔓延式扩张比例下降而填充式扩张和飞地式扩张不断增加,说明城市扩张模式由粗放蔓延型向紧凑集约型转换;(3)建设用地从快速扩张到稳定扩张的过程与植被覆盖从退化到管控的过程一致,印证了建设用地扩张与植被覆盖度的时空关联性。同时,建设用地扩张导致的生态系服务价值负值不断增加,较大幅度的降低了生态系统服务总价值。面临城市扩张进程中出现的植被覆盖退化和建设用地生态系统服务负值过大的问题,合理而有力的规划政策实施在未来城市发展中尤为重要。  相似文献   

10.
长三角地区城市土地开发强度特征及影响因素分析   总被引:1,自引:0,他引:1  
合理控制土地开发强度是提高土地利用效率和改善环境质量的重要手段。以建设用地面积占该区域土地总面积的比例为土地开发强度的表征指标,运用GIS软件和经济计量模型,探讨了1996~2008年长三角地区城市土地开发强度的特征及其影响因素。结果表明:长三角城市土地开发强度总体上呈增长趋势,城市间土地开发强度差异明显,并且具有空间集聚特征,形成了以上海、杭州为中心的高强度地区,这与目前长三角经济增长极相吻合。同时,经济增长、城镇化、产业结构与城市土地开发强度之间显著正相关,行政区划调整与城市土地开发强度在短期内表现为负相关关系,土地管理政策的影响尚不显著。今后,只有转变经济发展方式,严格执行土地管理政策和城市规划,合理推动城镇化和城市产业布局,才能使城市土地开发强度保持在合理水平。将为长三角地区城市土地可持续利用提供参考,对控制城市建设用地规模和发展方向,也有一定的理论和现实指导意义  相似文献   

11.
中国西部城市复合生态系统特点与生态调控对策研究   总被引:9,自引:1,他引:8  
城市是一类以人类活动为中心的社会—经济—自然复合生态系统。西部城市是西部大开发的重要铱托。本文首先介绍了中国城市与西部城市的发展概况,在与中、东部和全国城市比较的基础上分析了西部城市的城市化特点以及社会、经济和自然生态特点,并运用生态学原理和复合生态系统理论,提出了西部城市发展的生态调控对策。  相似文献   

12.
To analyze China’s actual urbanization level, we iden- tified two statistical approaches: using the population living within the administrative boundaries (administrative-based method) and within the urbanized or built-up areas (infrastructure-based method) of cities and towns as urban population. To illustrate the two approaches and the associated problems, we used data for Tangshan City as a case study. The estimates on the administrative-based method were unreliable and the infrastructurebased method pro...  相似文献   

13.
中国城市群的兴起催生经济集聚,化石能源消耗增多引发碳排放形势愈加严峻,探索经济集聚对碳排放强度的影响及传导机制至关重要。本文以2004-2016年京津冀、长江三角洲、粤港澳大湾区、成渝城市群的61个城市面板数据为研究样本,探索经济集聚与碳排放强度的关系及影响机制,创新性地使用抗日战争时期各城市是否有铁路通过、2003年各城市是否有机场、各城市历年的国家级经济技术开发区数量作为工具变量解决内生性问题,构建中介效应模型分别检验环境规制和城镇化水平对经济集聚影响碳排放强度的传导机制,并分析经济密度异质性下经济集聚对碳排放强度的不同作用路径。结果表明:①经济集聚与碳排放强度之间呈显著的负向关系,现阶段城市经济集聚水平的提高有利于降低碳排放强度;②相对于低经济密度城市,高经济密度城市经济集聚的降碳效果更为明显;③经济集聚不仅直接对碳排放强度产生影响,还通过环境规制与城镇化水平两条路径间接对碳排放强度产生作用,中介效应显著;④低经济密度城市经济集聚对碳排放强度的间接影响主要是通过城镇化水平来传导,而高经济密度城市经济集聚对碳排放强度的间接影响可以靠环境规制和城镇化水平两条路径来实现。据此本文认为,政府应推动城市群经济以促进区域融合发展,实现企业联动合作以提高经济集聚水平。针对经济密度不同的城市治理手段应有所侧重,高经济密度城市应以增强环境规制力度为主要碳减排手段,而低经济密度城市则应通过提高经济集聚水平,改善城市建设水平并最终达到碳减排的目标。  相似文献   

14.
As in many other developing countries, cities in Bangladesh have witnessed rapid urbanization, resulting in increasing amounts of land being taken over and therefore land cover changing at a faster rate. Until now, however, few efforts have been made to document the impact of land use and land cover changes on the climate, environment, and ecosystem of the country because of a lack of geospatial data and time-series information. By using open source Landsat data integrated with GIS technologies and other ancillary data, this study attempts to classify land use and create land cover maps, enabling post-classification change detection analysis. By this method, we document the spatial and temporal trajectory of urban expansion in Chittagong, the second largest city in Bangladesh, over a 36-year period. The findings suggest that, over the study period, 56 % of the land cover has undergone change, mainly because of the expansion of built-up areas and other human activities. During the 36-year period, the built-up area around Chittagong city has expanded by 618 %, with an average annual rate of increase of 17.5 %. As a result of rapid urbanization, the vegetated hills near urban development areas face serious threats of further encroachment and degradation, given that 2178 ha of hills have already been intruded over the study period. Because urbanization processes in Bangladesh have traditionally been viewed as the result of population growth and economic development, very little work has been done to track the potential growth trajectory in a physical or spatial context. This study, therefore, will contribute to the current understanding of urban development in Bangladesh from a temporal and spatial point of view. Findings will be able to assist planners, stakeholders, and policy makers in appreciating the dynamism of urban growth and therefore will facilitate better planning for the future to minimize environmental impacts.  相似文献   

15.
由全球气候变暖以及快速城市化引发的极端高温热浪事件频发现象已经影响到人类的生产和生活。利用多源卫星遥感数据和社会经济统计资料,构建基于"高温危险性-社会经济脆弱性-风险适应性"的高温热浪风险评估体系,获取2017年长江中下游城市群250 m分辨率的典型高温热浪事件风险评估结果。结果表明:热浪风险等级高值区主要分布在城市群中心城市以及其他城市中心城区,主要是较高的城市高温和社会经济脆弱性共同作用结果,围绕中心城区向外扩散,风险等级呈逐渐降低趋势。大城市虽具有更好的高温适应性,但离应对城市化导致的高温危险性和脆弱性还显得不足,从高风险区域面积来看,长三角城市群热浪风险高于长江中游城市群,主要与城市化水平以及人口聚集程度有关。通过多源遥感信息,获取高分辨率的城市群高温热浪风险空间分布特征,能为城市化过程中城市有效应对高温风险,加强区域防灾减灾提供科学参考。  相似文献   

16.
近年来,城市热岛效应不断增强,已经成为一个突出的城市环境问题。重庆市作为长江中上游特大型城市,工业发达,经济快速发展,市区热岛效应明显,但是很少对其研究。以2007年Landsat5 TM影像为数据源,利用单窗算法对重庆市城市地表温度进行反演,并进行城市地面亮温等级划分,在从城市土地利用类型、NDVI等方面对重庆市城市热岛效应强度和空间格局分布及其特征进行了探讨。结果表明:城区热岛现象显著,且分布不均匀;不同土地利用类型对热岛效应影响不同;城市地面亮温与NDVI呈明显的线性负相关关系。最后结合重庆市的特殊地形,提出了以下解决城市热岛效应的对策:加强城市规划,调整城市结构;构建最佳绿化结构,提高城市绿化率;改变能源结构,提高能源利用率,控制工厂废气排放量。  相似文献   

17.
Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades,which plays a very important role in promoting city development,whereas some side effects on the eco-environment appeared at the same time.This paper,taking Xi’an City in China as a case study site,analyzed the features of population suburbanization and industry suburbanization and pointed out the impacts of suburbanization on urban eco-environment.Based on the research,suggestions of countermeasures for urban planning and municipal management of Xi’an City in protecting urban eco-environment and conserving natural ecology were put forward in the end.  相似文献   

18.
新疆和田地区城市化与土地利用变化的定量分析   总被引:1,自引:0,他引:1  
选取自然环境和人文环境比较典型的西部欠发达贫困地区-新疆和田地区作为研究区域,借助国内外城市化与土地利用变化关系方面的理论和研究成果,分析城市化进程中土地利用变化的特征;采用回归分析方法,研究城市化与土地利用变化的相关关系及城市化进程对土地利用变化的影响程度.分析结果显示,城市化与耕地、居民点及工矿用地、交通用地和未利用地间有显著的相关性,表明城市化的快速发展是造成农业用地减少和建设用地增加的主要原因.同时,耕地与未利用地等两种土地类型和城市化间的负相关关系说明,两种地类的减少与城市化的快速发展有着密切的关系.这体现了和田地区城市建设和经济的快速增长是影晌生态环境等一系列有关可持续发展问题的重要原因.  相似文献   

19.
In the context of rapid population growth and urbanization, atoll countries have engaged in reclamation works and in the construction of coastal defences to extend inhabitable areas and reduce the threats posed by coastal erosion and flooding. Despite their major role in asset protection, coastal structures are still poorly documented. However, a better knowledge of the characteristics of these structures (location, type, condition, management status, etc.) would facilitate the establishment of consistent construction and maintenance programmes, and also contribute to a better understanding of shoreline changes. To address this need, this paper provides an assessment of coastal structures on Tarawa Atoll in Kiribati. The results highlight the abundance of structures, mostly seawalls (94.7 % of the total), which stretch along 29 % of the coastline. The protected shoreline decreases from urban (53.9 % at Bairiki) to rural islands (27.3 % at Buota), in proportion to population pressure. The occurrence and height of structures are greater on windward, ocean shores than on lagoon shores. Seawall condition is better in rural islands, compared to urban and semi-urban areas. The observed differences in the characteristics and physical condition of coastal structures mainly reflect differences in the management status of structures and the availability of building materials and funding. More generally, the occurrence and characteristics of coastal structures are strongly correlated to population densities, land-use dynamics and shoreline mobility. At some locations, the failure of coastal protection highlights the seriousness of the problems raised by land-use practices in Tarawa.  相似文献   

20.
随着工业化与城市化步伐的加快,城镇建设用地高速扩张,建设与粮食生产的矛盾日益突出,如何合理有效使用土地成为城市快速发展过程中迫切需要解决的问题。通过多时相遥感卫星影像,结合相关模型,分析和模拟建设用地扩展的时空特征,可以为城市土地合理配置与投放提供依据。利用 1987、1990、1997、2001、2006年的TM卫星遥感影像解译获得的建设用地数据,分析了南通近 20年来城镇建设用地变化和城区扩展特征,并且模拟了其扩展趋势。结果表明:南通市城镇建设用地扩展呈现明显的阶段性特征;其扩展的热点主要集中在沿江区域,沿海地区城镇建设用地扩展的热度逐步升温;城镇建设用地扩展显示出城镇组团化发展的趋势,尤其使南通大都市区的轮廓日益明晰。  相似文献   

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