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1.
In the background of China's rapid urbanization, the conflicts between urban population, economy, space, and environment are intensified and complicated. This article aims to establish a coordinate assessment method for studying urban population, economy, space, and environment interactions in city scale by principal component analysis and regression analysis. On the basis of the case study on Shenyang city, the results indicated that the integrated development of urban population, economic, and space was in a poor situation from 1993 to 1999, whereas it turned better after 2000, and the urban environment improved steadily after 1998. The static coordination degree of urban integrated development and environment showed obvious periodical and fluctuant characteristics. Compared with the static coordination degree, the dynamic coordination degree appeared to be smooth and lag. The static coordination degree was elementary discoordinative in 1993, 1994, and 1999; whereas it turned to be elementary coordinative between 1995 and 2005. The dynamic coordination degree was elementary discoordinative from 1993 to 1996, whereas it became elementary coordinative overall after 1997.  相似文献   

2.
在中国城市化迅速发展的背景下.城市人口、经济、空间与城市环境的矛盾日益复杂和激化,从可持续发展的角度出发.迫切需要研究城市人口、经济、空间与城市环境之闻的协调关系。运用主成分分析和回归分析等方法。在市区尺度上构建城市人口、经济、空阃与城市环境的协调评价体系,并以老工业城市沈阳为例,进行实证分析。分析结果表明:沈阳城市人口经济空间的综合发展于1993—1999年处于困境.2000年以后城市综合发展逐步好转;沈阳城市环境在1998年以后稳定上升;沈阳城市综合发展与城市环境的静态协调度具有明显的阶段性和波动性特征,动态协调度具有平滑和滞后性的特点;静态协调度于1993—1994年属于基本不协调阶段.1995—2005年基本处于协调状态。于1999年出现了低谷。并存在着下降的趋势;动态协调度于1993—1996年属于基本不协调阶段。1997年以后总体上属于基本协调阶段。  相似文献   

3.
Air pollution is a major environmental problem in urban areas worldwide. Delhi, the capital city of India, is no exception to the universal pattern of deteriorating urban air quality with concentration of pollutants being well above the recommended WHO levels. The magnitude and urgency of the problem as a global environmental issue needs a systematic understanding of the potential causes of pollution and their contribution to air quality. In the present study, ambient air quality data (1987–2006) of SO2, NO2, SPM, and RSPM were analyzed to asses the changing air quality in the study area and to evaluate the effect of measures taken to control it. The primary data were collected from 1,583 households to examine the relationship between outdoor and indoor pollution level. Based on the data, the current study concludes that despite the implementation of different pollution-controlling measures, the pollutants, especially the particulate pollutants, were well above the standard limits set by CPCB. Integration between technological and social approach of urban planning is required to mitigate and manage urban environmental problems in sustainable manner.  相似文献   

4.
Differences in natural 14C content of rings from trees from urban and rural locations have been compared on a year by year basis. The differences as a fraction of the urban tree's radioactivity reflect the local excess 14C-free carbon dioxide from fossil fuel combustion in the urban environment. New York City, Boston, and Washington, D.C., show different degrees of excess carbon dioxide. New York City averages about 6% excess carbon dioxide between 1950 and 1970. From this is infered an average carbon monoxide concentration during this period of 5 ppm.  相似文献   

5.
伴随着我国城镇化进程的不断加快,城市环境污染问题备受关注。本文以城镇居民生活垃圾污染行为为起点,通过比较居民与政府目标函数,首先从理论上做出判断,城镇人口数量增加以及居民生活质量提高均会导致城市生活垃圾数量增长,从而对城市环境产生影响。随后,进一步采取Panel data的分析方法,以我国2004-2008年省级面板数据为样本,从城市生活垃圾污染的角度对我国城镇人口增长、居民收入水平与城市环境间的关系进行计量检验。结果显示:我国城市生活垃圾产生数量分别与城镇人口增长、居民收入水平间存在着长期正向协整关系,即在我国城镇化水平和居民生活质量不断提升的背景下,城市生活垃圾数量的增长以及对城市环境的污染存在着内在必然性;另外,我国城市生活垃圾数量的自发增长对平均增长的偏离逐年下降,可见,存在政策、制度、行为等外生因素抑制我国城市生活垃圾数量的增长。最后,文章从生活垃圾控制和处理的角度,就改善我国城市环境和促进城市环境可持续发展提出了简要的政策建议。  相似文献   

6.
Global urban development is increasingly becoming an aspect of focus as nations fight sustainability challenges. A review of the current literature on urban sustainability suggests that research on development of cities, in both developed and developing countries, is growing fast, with an emphasis on sustainable development. However, very little of this research contains an integrated framework to systematically identify and examine the various dimensions of urban sustainability and to measure and evaluate them appropriately. Cities are more than the sum of their sectors, and are complex and interdependent systems on whose dynamics the quality of life of millions of human beings and a good part of the economy depend. Environmental, economic, social and governance problems can create formidable barriers to urban sustainability. Governance remains a critically important dimension of urban sustainability, especially when discussing urbanization in developing countries, given rapid population movements and imbalances in socio-economic development. Understanding how cities function is fundamental to resolving these imbalances. The aim of this paper is to provide a review and analysis of the concept of urban sustainability and to propose the development of a holistic framework through integration of environmental, economic, social, and governance dimensions of sustainability. Such a review would make it possible to understand the complex dynamics of the four dimensions and to assess the progress and challenges in moving towards urban sustainability, taking the case of Nairobi, Kenya, as an example. The paper argues that, for urban sustainability in developing countries, more emphasis should be placed on the governance dimension, because this is where the biggest challenge exists, with increasing needs for immediate management of rapid urbanization.  相似文献   

7.
Recent investigations in Russia have emphasised the significance of dose contributions from contamination on urban streets and roof pavings, and, typically to a lesser extent, walls in the urban environment. The crucial factor determining the magnitude of these contributions is the retention of the contamination by the different types of urban surface. Since the Chernobyl accident, a series of long-term field studies has been carried out on urban streets, walls and roofs, to examine the weathering processes of 137Cs on the various surface types. The derived time-functions are applied to estimate resultant long-term doses to inhabitants of an urban centre. The paper highlights the effect on caesium retention of surface material characteristics.  相似文献   

8.
Environment, Development and Sustainability - The rapid urban growth in mid-sized cities of developing nations has induced conflict between development and the environment, often leading to urban...  相似文献   

9.
Abstract: his paper explored the relationships among nonagricultural population, employment and land in an integrated framework, taking account of rural-urban land conversion into Carlino-Mills's model on the regional growth. Two-stage-leastsquares and ordinary-least-squares were employed. Recent data for district (grade) cities in China (from 1999 to 2005) were used. Our results showed that: first, urban population influenced non-agricultural employment, and vice versa, but the evidence that non-agricultural employment influenced urban population was stronger than the evidence that urban population influenced non-agricultural employment; second, urban population and non-agricultural employment both influenced ruralurban land conversion, but the evidence that urban population influenced rural urban land conversion was more stronger than the evidence that non-agricultural employment did. We also found that: first, the employment from the secondary industry influenced urban population in a positive way, and vice versa, but the employment from the tertiary industry influenced urban population in a negative way, and vice versa; second, the employment from the secondary industry influenced rural-urban land conversion in a positive way, but the employment from the tertiary industry influenced rural-urban land conversion in a negative way. We can conclude that the key of urbanization is to speed up the process of non-agricultural employment, especially the employment from the tertiary industry, which might promote non-agricultural population, employment and land harmoniously.  相似文献   

10.
Abstract

This paper explored the relationships among nonagricultural population, employment and land in an integrated framework, taking account of rural-urban land conversion into Carlino–Mills’s model on the regional growth. Two-stage-leastsquares and ordinary-least-squares were employed. Recent data for district (grade) cities in China (from 1999 to 2005) were used. Our results showed that: first, urban population influenced non-agricultural employment, and vice versa, but the evidence that non-agricultural employment influenced urban population was stronger than the evidence that urban population influenced non-agricultural employment; second, urban population and non-agricultural employment both influenced ruralurban land conversion, but the evidence that urban population influenced rural urban land conversion was more stronger than the evidence that non-agricultural employment did. We also found that: first, the employment from the secondary industry influenced urban population in a positive way, and vice versa, but the employment from the tertiary industry influenced urban population in a negative way, and vice versa; second, the employment from the secondary industry influenced rural-urban land conversion in a positive way, but the employment from the tertiary industry influenced rural-urban land conversion in a negative way. We can conclude that the key of urbanization is to speed up the process of non-agricultural employment, especially the employment from the tertiary industry, which might promote non-agricultural population, employment and land harmoniously.  相似文献   

11.
为探究城市建设用地集聚对城市建设用地利用效率的作用机理,文章基于2003—2017年中国278个地级及以上城市面板数据,通过构建多产出随机前沿生产函数模型测度城市建设用地利用效率,采用时间-空间双固定的空间杜宾模型探讨了不同程度的城市建设用地集聚对利用效率的影响机理与差异。结果表明:(1)从时空特征上来看,样本考察期内中国城市建设用地利用效率总体上呈稳步提升趋势,东部城市建设用地效率最高,西部次之,中部最低。(2)从全国维度的空间计量模型回归结果来看,城市建设用地集聚所带来的规模效应和外溢效应对城市建设用地利用效率具有改进作用,有利于利用效率进一步提升。(3)从不同城市建设用地集聚度分群回归结果来看,高集聚城市(东部发达地区)的直接效应显示随着城市建设用地集聚度的提高,利用效率也不断提高;间接效应中,建设用地集聚度的提高对周边城市的利用效率产生先带动后抑制的"倒U"形作用。低集聚城市(中西部欠发达地区)的直接效应和间接效应均显示,随着城市建设用地集聚的提高,其利用效率存在"先降后升"的"U"形曲线特征。可见,在城市发展的不同阶段,城市建设用地集聚对城市土地利用效率存在差异化影响。因此,中国城市发展应立足当前发展阶段特征,制定差别化的供地政策,促进城市建设用地集聚,针对性地提升区域要素利用效率,支撑经济社会进一步发展。  相似文献   

12.
乌鲁木齐可持续城市发展战略研究   总被引:7,自引:0,他引:7  
本文系统地分析了可持续城市发展的支持系统和主要问题,提出了新世纪乌鲁木齐可持续城市发展战略及其目标、方针与重点,指出了乌鲁木齐可持续城市发展的战略模式。  相似文献   

13.
城市热环境的规划改善策略研究——以武汉市为例   总被引:1,自引:0,他引:1  
随着城市热环境的恶化,城市中极热现象频率逐步增高。对于在城市尺度下提出的概念性的规划策略,因其缺乏可操作性并不能及时有效的缓解城市热岛现象。然而,在局部尺度下的策略一直难以提出,其中的一个原因便是对现有的关于城市微气候的研究缺少标准。在OKE教授团队提出的局部气候区(LCZ)概念的基础上,以武汉市为例提出一个通过量化的措施在局部尺度改善城市热环境的流程。方法上,利用ArcGIS和envi软件从Landsat-7的ETM+影像数据和武汉市的建筑矢量数据中提取出9个最常用的影响地表温度(LST)的地表指标,进而利用这9个指标通过K均值聚类的方法对武汉市研究区域进行LCZ划分。接着,利用普通最小二乘法(OLS)分析地表指标与LST的关系。以LCZ为框架,结合各地表指标与LST的相关性关系,从改善局部LST过高的角度出发,以分层结构和优先级的思路提出规划缓解策略。研究结果表明,案例中的武汉市研究区域被划分为7个LCZ,同时也定位出各LCZ中温度最高的热点,发现地表指标在不同的LCZ与地表温度有独特的相关性关系,因而针对不同LCZ中的热点提出了具体的地表指标参数值调整建议来改善热点的热环境状况。这可以在一定程度上有目标性的降低局部热岛的温度,同时至少在2个方面有助于城市微气候和规划的研究:(1)减小了城市热环境的研究尺度;(2)从规划角度提出了优化城市热环境的工作流程。  相似文献   

14.
To address the growing need for developable land, many coastal cities are draining and filling wetlands, transforming them into urban built-up areas, and thereby substantially altering the structure and function of coastal ecosystems. We demonstrate an integrative approach for investigating the dynamics and impacts of coastal development in China’s Jiangsu Province, where urban expansion has resulted in extensive wetland losses and sea reclamation (the process of creating new land from ocean or coastal waters). Remotely sensed data reveal that landscape change in the study area has been accompanied by an increase in total impervious surface area and an increase in mean surface “heat island effect.” These indicators of change can be detected with remote sensing data and used to support a strategic environmental assessment (SEA) for urban coastal planning. Changes detected in Lianyungang during 2000–2006 suggest that reclaimed areas are environmentally sensitive and should be a focus of concern in future development planning, which has historically targeted coastal salt pond wetlands for conversion to land for the development. Given the current and projected rate of coastal development in China and elsewhere in the developing world, our findings and assessment approach have implications for coastal management decisions in the developing coastal zones of China and other regions of the world that are experiencing rapid urban growth.  相似文献   

15.
Environment, Development and Sustainability - The variation in the atmospheric conditions of urban areas to the fringe areas is termed as urban heat island and is attributed predominantly to the...  相似文献   

16.
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   

17.
Tehran metropolitan region (TMR) has experienced rapid urbanization in the last few decades. This accelerating urbanization trend mainly arising from high natural population growth and rural–urban migration along with rapid socioeconomic changes formed unplanned and uncontrolled urban expansion in peri-urban areas and resulted in degrading environmental quality and considerable changes in the urban landscapes of the TMR. Thus, the main objective of this research is to model spatial pattern of urban growth in eastern corridor of TMR using GIS-based SLEUTH model and the prediction of future developments of the region from 2014 to 2060. The SLEUTH is one of the most powerful models for urban growth modeling. This model analyzes the spatial pattern of urban growth based on historical data obtained from satellite images of 1987, 2003, 2011, and 2014. The results indicate that the most important factors affecting the urban growth are slope resistance and road gravity. The slope resistance is the highest coefficients value, which illustrates the limiting influence of the slopes on general trend of urban growth in eastern corridor of the TMR. The road gravity stands in second place where it displaces orientation of linear form of outlying pattern alongside the transportation network; it represents that the main pattern of urban growth in peri-urban areas of the region have a linear nature and edge expansion due to slope resistance and road-influenced growth, while spread, diffusion, and breed coefficients display low probability of new spreading center and spontaneous growth in the study area. In addition, the prediction of urban growth for 2020–2060 revealed that urban expansion which was 41,500 ha in 2014 will increase to 179,400 ha in 2060 with noticeable growth rate of 145.6 %. Comparing study area and other researches indicate that the urban growth happens in high rate in eastern corridor. One of the main reasons of this growth goes back to the formation of the second homes for residents of Tehran metropolitan city.  相似文献   

18.
Current international discussions on the increasingly critical levels of carbon emissions from the transportation sector commonly attribute the causality chain to urban sprawl growth–private car use–carbon emission. An often assumed development context of this causality chain is that common of developed country urbanization. However, in the particular context of developing country urbanization, urban sprawl and associated workplace–home distanciation may lead to more intensive use by the urban workforce of public mass transportation system, instead of higher dependence on private vehicle travel. Thus, the source of the rise in carbon emission may actually be the public transportation system. Utilizing mixed methods, combining quantitative (origin–destination matrices) and qualitative data gathering and analysis, the authors present a case study in Metro Manila which has been experiencing sprawl and increasing costs and unaffordability of land and housing in the workforce’s vicinity of employment. This, in turn, causes greater distances of daily travel between home and workplace using public transportation system. When the latter is characterized by fuel-inefficient small vehicles with second-hand engines, higher carbon emission results. We argue that the convergence of multiple interacting factors such as urban sprawl, lack of affordability of housing near the centres of employment, high dependence of commuters on public transports, longer distance travel by commuters, and low fuel efficiency of the public utility vehicles primarily causes the increase in CO2 emission from the transport sector. Implications of this case to policy scoping of immediate and long-term state responses for carbon emission mitigation in transportation sector are discussed.  相似文献   

19.
This paper aims to estimate the effects of changing life style and consumption demands driven by income growth and urbanization on increase of energy requirements in China, and es-timate the impacts of improvement in household consumption on mitigating energy requirements towards 2020, based on input-out-put analysis and scenarios simulation approach. The result shows that energy requirement per capita has increased by 159% for urban residents and 147% for rural residents from 1995 to 2004. Growth in household consumption driven by income growth and urbanization may induce a successive increase in energy require-ments in future. Per capita energy requirements of urban residents will increase by 240% during 2002-2015 and 330% during 2002-2020. Urbanization might lead to 0.75 billion ton of increment of energy requirements in 2020. About 45%-48% of total energy requirements in China might be a consequence of residents’ life styles and the economic activities to support consumption demands in 2020. Under low-carbon life style scenario, per capita energy requirements of urban residents may decline to 97% in 2015 and 92% in 2020 in contrast with baseline scenario. That implies that China needs to pay a great attention to developing green low-carbon life style in order to realize mitigation target towards 2020.  相似文献   

20.
湖南怀化地区96.7城市特大洪涝灾害成因分析   总被引:1,自引:1,他引:0  
湖南省怀化地区地形以山地为主,该地区1996年7月发生了城市特大洪涝灾害,本文概述了该地区96.7城市洪涝灾情,并以区域灾害系统论为指导,从孕灾环境、致害因子、承灾能力和人类活动的不利影响等方面,对这次灾害的成因进行了分析,认为其主要成因是:(1)易洪涝的山丘区环境;(2)96.7降雨强度大、覆盖面广、持续时间长的异常雨情和高洪峰水位、流量的异常水情;(3)城市防洪标准低、水利水电工程防洪效益差和抗洪害意识不强等原因造成的城市防洪能力低;(4)砍伐森林、人为侵占河道和大型水库超常规蓄水等人类活动造成的不利影响。  相似文献   

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