研究中国城市化理论学派述评   总被引：17，自引：3，他引：14  

薛凤旋  蔡建明 《地理研究》1998,17(2):208-216

中国城市化具有独特性,自70年代以来一直成为学术界的研究热点之一.文中通过对各有关研究的比较和总结,归纳出5种最具代表性和影响力的学说,即反城市主义说、工业战略说、城市二元体系和工农业均衡发展说、工业化和城市偏爱说以及综合说,并对各学说进行了评述,指出中国在面临社会经济结构全面转型的历史时期,极有必要借鉴他人的研究方法和成果去建立自己的新理论.  相似文献   

A global analysis of urbanization effects on amphibian richness: Patterns and drivers     

《Global Environmental Change》2022

Urbanization presents an unplanned and highly replicated global experiment to understand biotic responses to global changes. Here we conducted a global analysis on patterns and drivers of urbanization effects on biodiversity using the global amphibian richness dataset along with background climate and the continuous rural-urban gradients. We, for the first time, empirically generalized the urbanizational gradients of amphibian richness at the global scale and in different climate zones despite the substantial differences in history, ecological context, and socioeconomic conditions across large geospatial extents. We found a positive imprint of urbanization on amphibian richness in cool and climate zones whereas the presence of urban thermal stress in high temperature climate zones. Anthropogenic forces behind the urbanization gradients entangled with environmental variables directly and indirectly drove the patterns as revealed by the structural equation modeling (SEM). The urbanizational diversity gradient (UDG) found in this study might signify the existence of another general principle in ecology analogous to well-known latitudinal and elevational diversity gradients. We proposed the heat-and-threat balance (HATB) hypothesis to explain UDG: urbanization-induced heat would promote biodiversity if the ambient temperatures are cooler than their optima. Alternatively, it may put threats on biodiversity when the ambient temperatures are close to their optima. There is an urgent need to advance the knowledge on UDG in an urbanizing planet by additional studies from diverse taxa, various geographical locations, and at different scales.  相似文献   

Arcellacean (thecamoebian) evidence of land-use change and eutrophication in Frenchman’s Bay, Pickering, Ontario     

E. G. Reinhardt  M. Little  S. Donato  D. Findlay  A. Krueger  C. Clark  J. Boyce 《Environmental Geology》2005,47(5):729-739

Frenchmans Bay, on the northern shore of Lake Ontario, has been negatively impacted by eutrophication in the last 50 years through urbanization and the use of chemical fertilizers. Eutrophication began with wholesale land clearance and agricultural practises beginning in the mid-nineteenth century and reached a peak with urbanization after World War II. Eutrophication and the effects of land-use changes on the watershed were investigated by a combined analysis of the sediment magnetic properties and arcellacean (thecamoebian) microfauna. Micropaleontological analyses were conducted on two 2-m-long cores (FMB1 and FMB2) every 10 cm (42 samples) and magnetic susceptibility was measured at 2-cm intervals. Both cores showed a distinct correlative transition at 60 cm and 110 cm that was marked by a rapid increase in thecamoebian concentrations (from approx. 10×10³ to 30×10³ specimens per cc) and a large increase in Cucurbitella tricuspis (from approx. 10–20% to 40–70%). This transition correlated with a marked increase in magnetic susceptibility (150–200×10^–8 m³ Kg^–1) at the same depth, which was attributed to elevated levels of detrital magnetic minerals derived from land clearance and soil erosion in the watershed. It was indicated by ²¹⁰ Pb dates indicate that there was a gradual onset of eutrophication in the mid-nineteenth century (AD 1850±56) and a more rapid rise in the mid-1940s to late 1950s. The initial increase in eutrophication was due to land clearing, agricultural development and increased nutrient loadings. The major eutrophication increase in the 1950s was from urbanization and storm sewer discharge loaded with high yield chemical fertilizers from lawns and gardens. This high concentration of nutrients has led to an unprecedented level of eutrophication within the wetland.  相似文献   

Global urbanization projections for the Shared Socioeconomic Pathways     

《Global Environmental Change》2017

The new scenario process for climate change research includes the creation of Shared Socioeconomic Pathways (SSPs) describing alternative societal development trends over the coming decades. Urbanization is a key aspect of development that is relevant to studies of mitigation, adaptation, and impacts. Incorporating urbanization into the SSPs requires a consistent set of global urbanization projections that cover long time horizons and span a full range of uncertainty. Existing urbanization projections do not meet these needs, in particular providing only a single scenario over the next few decades, a period during which urbanization is likely to be highly dynamic in many countries. We present here a new, long-term, global set of urbanization projections at country level that cover a plausible range of uncertainty. We create SSP-specific projections by choosing urbanization outcomes consistent with each SSP narrative. Results show that the world continues to urbanize in each of the SSPs but outcomes differ widely across them, with urbanization reaching 60%, 79%, and 92% by the end of century in SSP3, SSP2, and SSP1/SSP4/SSP5, respectively. The degree of convergence in urbanization across countries also differs substantially, with largely convergent outcomes by the end of the century in SSP1 and SSP5 and persistent diversity in SSP3. This set of global, country-specific projections produces urbanization pathways that are typical of regions in different stages of urbanization and development levels, and can be extended to further elaborate assumptions about the styles of urban growth and spatial distributions of urban people and land cover occurring in each SSP.  相似文献   

Frontiers of urbanization: Identifying and explaining urbanization hot spots in the south of Mexico City using human and remote sensing     

《Applied geography (Sevenoaks, England)》2017

This article applies a multi-method approach to develop a better measurement of urbanization dynamics using remote and human sensing based on a GIS platform. The results demonstrate the benefits of bringing human and remote sensing sources together in a framework of hot spot analysis for a megacity such as Mexico City. Furthermore, our analysis suggests that human and remote sensing work well together in detecting the expansion of illegal urban settlements. Looking at the driving factors of illegal settlements, the existence of strong association between the expansion of illegal urban settlements and socioeconomic factors such as unemployment, provides some answers and reveals new questions. Illegal urban growth often leads to the loss of ecological areas in the urban frontiers, especially in areas where the urbanization potential is high. As a consequence, there are conflicts with legal settlers who dislike the illegal expansion. This approach can be extended to and replicated in new urbanizing areas, in particular in Africa and Asia.  相似文献   

城市化对近地层风速概率分布及参数的影响   总被引：1，自引：0，他引：1  

吴息  吴文倩  王彬滨 《气象学报》2016,74(4):623-632

通过地面风速Weibull概率分布参数的阶段变化来描述城市化对地面风速的影响,并通过理论分析得出城市化进程导致其尺度参数c缩小,位置参数r增大的趋势效应的结论。将北京等8个城市1982—2005年地面天气资料定时数据按时间划分为前、后两个时段,分别拟合分布曲线的参数,对比前、后两个时段的拟合结果,验证了理论分析所得结论,即随城市的发展,各城市风参数c不同程度地缩小,r不同程度地增大,同时概率密度曲线的峰值均增大;不同城市的风速概率密度函数曲线变化特征有所不同,根据前、后时段概率密度曲线变化的特征,8个城市风速概率分布变化大致可分为A、B两种类型,两者的主要差异是A型变化特征为在曲线两端(大风和静风)的概率都减少,曲线分布更加集中;B型则是大风概率减少而静风的概率则增大,曲线向左移动;A型变化城市的r参数平均增大46.3%,明显大于B型城市的15.7%。初步资料分析还表明,风参数c和r变化幅度与城市化扩张速度有关。  相似文献   

1980~2013年安徽霾天气变化趋势及可能成因   总被引：4，自引：0，他引：4  

石春娥  王喜全  李元妮  邓学良  杨元建  温华洋 《大气科学》2016,40(2):357-370

对1980~2013年安徽省霾日数的时空变化趋势及可能原因进行了分析,结果表明:(1)1980年以来,霾天气年均发生日数总体呈上升趋势,年际波动较大。不同年代,霾高发区的位置不同:20世纪80年代平均为5.5 d,沿江到江淮之间有零星的高发区;20世纪90年代平均为8.5 d,高发区在沿江中西部的望江和池州、省会合肥、淮北北部的萧县和灵璧;2000年代,平均发生日数为8.7 d,有3个高发区,分别是以合肥为中心的江淮之间中部、沿淮中部地区和沿江中东部地区。(2)按地理位置把安徽省分为6个子区,不同子区年霾日数的变化趋势不同:皖南山区变化较平缓,沿淮地区2000年后上升明显,淮北北部和沿江有先升后降的趋势。(3)地级市平均霾日数呈显著上升的趋势,而县城霾日数上升速度缓慢,且在2008年之后有下降趋势。(4)城市化和汽车拥有量激增导致氮氧化物排放量快速增多,可能是2000年之后地级市霾日数显著增多的主要因子,而县城霾日数变化的驱动因子可能是气候变化原因,如东亚季风强度的变化。  相似文献   

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

Robert Barouki  Manolis Kogevinas  Karine Audouze  Kristine Belesova  Ake Bergman  Linda Birnbaum  Sandra Boekhold  Sebastien Denys  Celine Desseille  Elina Drakvik  Howard Frumkin  Jeanne Garric  Delphine Destoumieux-Garzon  Andrew Haines  Anke Huss  Genon Jensen  Spyros Karakitsios  Jana Klanova  Paolo Vineis 《Chemie der Erde / Geochemistry》2012

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   

长三角城市群下垫面变化气候效应的模拟研究   总被引：4，自引：3，他引：1  

花振飞  江志红  李肇新  马婷婷 《气象科学》2013,33(1):1-9

利用法国动力气象实验室发展的高分辨可变网格大气环流模式LMDZ,分别通过LMDZ的高分辨可变网格区域版及其全球版模式的数值模拟,研究长三角城市群下垫面变化带来的夏季气候效应,并尝试探讨大尺度环流的响应.其中LMDZ高分辨区域模式的模拟结果表明长三角城市群下垫面变化可导致夏季长三角地区接受的净辐射明显增加,感热通量上升,潜热通量下降,引起局地地表温度显著上升.同时西太平洋副热带高压西伸北抬控制长三角地区,反气旋性水汽通量异常,导致该地区降水异常减少.进一步对LMDZ全球模式的模拟结果分析,发现长三角城市群下垫面变化可能会引起大气基本模态的变化,进而引起南北半球中高纬异常波列结构的出现.  相似文献   

太湖湖陆风背景下的苏州城市化对城市热岛特征的影响   总被引：6，自引：2，他引：4  

杨健博  刘红年  费松  张宁  蒋维楣 《气象科学》2013,33(5):473-484

利用南京大学区域边界层模式,选取苏州地区2006年8月12日晴天小风的天气作为背景天气条件进行算例的模拟。分析了该地区在湖陆风环流背景下的城市化进程对热岛特征的影响。结果表明:苏州地区的风场受大尺度系统、湖陆风环流和城市热岛环流系统的共同影响,且湖陆风环流的强度大于热岛环流。苏州地区的城市热岛影响高度可达400 m左右,且在背景风场的影响下,该地区的温度分布会体现出比较明显的下游效应特征,下游效应的距离可达10 km左右。这种下游效应在400 m高度以下比较明显,随高度的升高而逐渐减弱。20 a的城市化进程(1986—2006年)导致苏州城区地表感热通量增加了200 W/m²、潜热通量减少了200 W/m²、湍能增加了0.045 m²/s²、日平均热岛强度增加了0.4 ℃;热岛环流加强,并使白天混合层最大高度升高了400 m,但对夜间逆温层发展的影响较小。太湖湖陆风,使靠近太湖的苏州市郊的混合层、逆温层高度明显下降,但对距离较远的苏州市区的混合层、逆温层高度影响不大。且太湖的存在对于城市化进程导致的苏州地区热岛强度增加、地表湍流动能增加、感热通量增加、潜热通量减少的趋势有比较明显的缓解作用。  相似文献