广西城市发展的回顾与展望   总被引：1，自引：0，他引：1  

章牧 《热带地理》1998,18(2):172-176

尖回顾改革开放以来广西城市发展历史的基础上,分析了广西城市化的现状特征;从自然资源、社会经济背景、交通及区位条件等方面出发,说明了广西城市发展的区域基础,并对于今后广西建设与发展的思路,提出了一些设想和建议。  相似文献   

中国西北干旱地区城市化过程及空间分异规律   总被引：4，自引：0，他引：4  

段汉明  周晓辉  苏敏 《地球科学进展》2004,(Z1)

通过对实地调研和大量文献分析,对我国西北干旱地区城市发展与自然环境的关系进行论述,认为城市化过程本质上就是人地关系的集中凸现,是自然要素与人文要素长期互相作用的结果。自古以来,城市就是人类聚居的主要场所,屯垦是西北干旱地区最能体现人地关系的耦合点。在西北干旱地区现代城市化过程中,屯垦和矿产资源开发有较大的带动作用。由于自然因素和社会因素的双重影响,人口分布和聚居程度极不均衡,社会经济分异较大,城镇功能单一,部分地区和城镇的人口城镇化水平较高,并不是社会经济整体发展的结果,而是资源开采、行政建制的设立、极端自然条件下生存的需要等多种因素形成的。城市分布空间格局以带状、团状、串珠状为主,有着不同于其他地区的演化模式,城镇发展表现出多元复合的特征,是政治、经济、生态环境、资源、民族与文化等诸多因素相互关联、起伏变化的结果。城镇高速发展、城市化速度加快是未来西北干旱地区社会经济发展的必然结果,面对脆弱的生态环境和有限的资源,提出在西北干旱地区建设只有城镇、没有村落的新型城市社会,以达到社会经济和生态环境可持续发展的目标。  相似文献   

提高城市化水平与耕地面积变化的的关系研究——对大连市的实证研究   总被引：4，自引：0，他引：4  

栾维新  王茂军 《地理科学》2002,22(2):208-212

在对城市化水平与耕地面积关系综合分析的基础上 ,通过对大连市域城市化水平提高与耕地面积变化之间关系的实证研究 ,得出以下结论 :①人均建设用地与居民点规模呈反向变化 ;②大、中城市建设用地基本可以得到控制 ,农村居民点用地的控制难度较大 ;③在充分挖掘农村居民点内部潜力的前提下 ,随着城市化水平的提高 ,各类居民点人均建设用地的总规模将减小 ,提高城市化水平是缓解耕地供需矛盾的重要途径。  相似文献   

快速城镇化进程中太湖流域产水量变化的时空分布特征     

李伶杰  胡庆芳  王银堂  刘勇  朱琰  王磊之  崔婷婷 《湖泊科学》2019,31(5):1289-1298

快速城镇化进程中太湖流域下垫面的剧烈变化对流域产水量时空分布产生了深刻影响.在分析太湖流域城镇化进程及土地利用变化的基础上,采用太湖流域模型对3种典型降雨过程（1991、1999和2009年）与5种下垫面（1985、1995、2000、2005和2010年）的组合情景进行模拟,综合分析了城镇化进程中全流域和各水利分区在全年期、汛期、涨水期产水量变化的时空分布特征.结果表明：时程上,太湖流域和所有水利分区的各统计时段产水量增幅伴随城镇化进程推进均呈现增加趋势,2005年后产水量增幅进一步加大,且全年产水量增幅主要集中在汛期;空间上,东、中部城市集聚区的产水量增长率明显高于西部山丘区与太湖湖区,这主要是由于西部山丘区、太湖湖区不透水率增幅较小所致.产水量变化的时空非均匀分布特征为城镇化背景下太湖流域防洪除涝格局演变及流域-区域-城市防洪除涝协调性研究提供了重要的先验认识.  相似文献   

近30年来南四湖流域城市化进程中的水系变化分析   总被引：1，自引：1，他引：0  

江燕  薛丽芳  于红学  孟瑶瑶 《湖泊科学》2017,29(1):135-142

城市化对水系演化影响的研究国内目前多集中在快速、高速城市化地区,而对大流域、城市化发展较缓地区的研究比较薄弱.以南四湖流域为研究区,基于1987、2000和2014年3期遥感影像,分析了流域城市化进程中的下垫面变化特征;选取流域1980s、2003和2014年的地形图进行水系提取,从数量参数、结构参数和连通性参数3个角度分析近30年城市化进程中水系结构的时空变化特征.结果表明:(1)近30年来流域建设用地增加了1568.06 km~2,2000年以后城市建设用地扩张显著,2012年流域人口城市化率为32%;(2)1980s—2010s流域总河流长度、面积和河网密度均呈现出持续减少趋势,分别减少了135.46 km、2.75 km~2和0.49 km/km~2,各级河流表现出不同的变化特点,较低等级河流受到的影响较大;而流域水面率持续增加,近30年共增加了59.79%;(3)流域水系总体上还保持着自然状态下的空间格局,但结构特征发生了较大改变,河网结构稳定度减少了4.30%,连接率和实际结合度分别减少了21.82%和21.62%;子流域内部距湖区越远的空间城市扩展强度指数值越大,城市化对水系的影响越显著.该研究将补充对不同空间尺度、不同城市化水平地区河网水系演化影响的案例,并为研究区河网水系的保护提供支持与参考.  相似文献   

城市化背景下年最大日径流演变及影响因素研究——以长江下游秦淮河流域为例     

罗爽  许有鹏  王强  于志慧  林芷欣  唐仁  江如春 《湖泊科学》2023,35(6):2123-2132

随着气候变化和人类活动的加剧,城市化地区水文过程受到较大影响,极端水文事件发生频率显著加大,探究城市化地区洪水演变和驱动机理对于防洪减灾具有重大意义。本文以长江下游快速城市化地区的秦淮河流域为例,分析了1987—2018年期间该流域年最大日径流的演变特征,构建多元线性回归模型和广义可加GAMLSS模型识别了关键驱动因子并量化其贡献作用。结果表明:(1)城市化背景下秦淮河流域年最大日径流呈现显著上升趋势,平均增长速率为14.77 m³/(s·a),并于2001年发生显著突变。(2)汛期降水量和不透水面率是年最大日径流变化的关键驱动因素,最优模型显示前者贡献率超过了70%,表明了降水改变的决定性作用,而不透水面率贡献率超过20%则表明了下垫面的改变对年最大日径流演变存在显著影响。(3)不透水面的增加对年最大日径流和汛期降水量响应关系的影响程度从突变前的6.7%增加到突变后的10.4%,快速城市化已显著改变了流域降水-径流响应过程。研究表明,随着城市发展秦淮河流域的年最大日径流受到人类活动显著影响,洪涝威胁日趋增大,研究结果可为城市化地区防洪减灾提供一定参考。  相似文献   

Megacities – megarisks     

Friedemann Wenzel  Fouad Bendimerad  Ravi Sinha 《Natural Hazards》2007,42(3):481-491

We review the definitions, population trends, and characteristics of megacities. Characteristics of megacities are, apart from their size, their complexity in terms of administration, infrastructure, traffic, etc., and at the same time the speed of change. Vulnerabilities and risk potential are discussed using the examples of Mexico City and Mumbai. We present the experience accumulated in the 6 years work of the Earthquakes and Megacities Initiative (EMI, ) with more than 20 large cities around the world, mostly located in the developing world. On this background we analyze obstacles that keep megacities from developing an efficient approach towards disaster mitigation and define a strategy that might overcome these problems. The key element of this strategy is the development of a Disaster Risk Management Master Plan (DRMMP) for cities. Currently the Istanbul Earthquake Master Plan (IEMP) serves as best example for an appropriate strategy for disaster reduction in megacities.  相似文献   

Urbanization and water management in Ho Chi Minh City,Vietnam-issues,challenges and perspectives     

Phu Le Vo 《GeoJournal》2007,70(1):75-89

The management of water resources is an unfinished effort of the international community. Rapid urbanization has transcended the management capacity of governments in developing countries. Since the renovation policy launched in 1986, Ho Chi Minh City, Vietnam, has experienced the fastest urbanization and industrialization process. This has placed severe constraints on the use of water resources and management capacity of the local government. The abstraction of groundwater has exceeded the limiting volume (520,000 m³/day) and the annual drawdown of water table is 2–3 m. In addition, the quality of urban water bodies is increasingly exacerbated by a huge volume of untreated industrial and domestic wastewater. These are hampering water demand, use and the capacity of the municipal authority in managing water resources. The purpose of this paper is to analyze the impact of urbanization on water resources. Current issues and challenges in the management practices of water resources are discussed. It will propose a new paradigm of water management in Ho Chi Minh City.  相似文献   

Urbanization and class-produced natures: Vegetable gardens in the Barcelona Metropolitan Region     

Elena Domene 《Geoforum》2007,38(2):287-298

This paper examines urban vegetable gardens in the Metropolitan Region of Barcelona (MRB) in the context of a political ecological approach. We argue that these gardens provide an interesting example of how the urbanization process creates particular “socionatures” linked in this case to retired members of the working class who occupy (often as squatters) and transform the interstices left by the expanding city in order to produce food at a small scale. We document how these vegetable gardens are the product of a peculiar form of the recent urban history of the area, and also how they are increasingly under pressure due to the rapid process of sprawl now characterizing the expansion of the built environment in the Barcelona region. Vegetable gardens also highlight the contradictions of public policies in managing urban development, since the general attitude towards their elimination from the urban landscape stands in opposition to many of the sustainability initiatives such as the “greening of cities” promoted by city councils in this area.The empirical analysis was carried out in the municipality of Terrassa, one of the largest cities in the MRB, and also one with a higher number of vegetable gardens. We interviewed 132 plot users and obtained data about the legal status of gardens, their size and appearance, and crops grown, as well as the reasons for pursuing this activity. Our results show that, in general, this is an activity undertaken by people over 60 years old, often retired members of the working class that migrated to Catalonia from other Spanish regions in the 1960s and 1970s, and that use these spaces for a variety of reasons (personal goals, support to their families, and also as a bond to their rural past). Finally, we develop some conclusions regarding vegetable gardens in which we maintain that different social classes may create different natures but that class and power relations appear to legitimize some of these natures over others, for example, private and public gardens having a much larger social and institutional appeal and support than the vegetable gardens of the retired workers.  相似文献   

The COVID-19 pandemic and global environmental change: Emerging research needs     

《Chemie der Erde / Geochemistry》2006

The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs.  相似文献