Research Progress on the Impact of Urbanization on Climate Change

The world has been undergoing a remarkable process of urbanization, especially in developing countries in recent years. The urbanization process has brought about great urban development and large population agglomeration, changes in production and lifestyle, and man-made disturbances such as greenhouse gas and pollution emissions. As the global urbanization process continues to advance, its impact on climate change continues to strengthen significantly. This paper mainly reviewed and summarized relevant researches from two aspects: the influence of urbanization on climate change and the mechanism of influence of urbanization on climate change. Urbanization causes regional warming and urban heat island effect, extreme events such as high temperature, heat wave and heavy rainfall increase in frequency, and also leads to increased urban flood risk. The increase of pollutant emission in the process of urbanization is the main cause of air quality deterioration. Urbanization also has an indirect impact on air quality by changing urban climate. Urbanization has an important impact on climatic factors such as relative humidity, wind speed, sunshine and cloud cover. The impacts of urbanization on climate change are mainly realized through underlying surface changes, greenhouse gas and pollution emissions, anthropogenic heat emissions and urban high heat capacity. Urbanization not only directly affects the regional/local climate, but also indirectly affects the regional/local climate by promoting global climate change. Therefore, the impact of urbanization on climate change has a global and regional multi-scale superposition effect.     

基于MIKE 11的北京市典型区域降雨径流特征研究

以北京城市化发展区凉水河大红门闸控制流域为典型区域,在分析区域20世纪80年代到2000年后下垫面变化特征的基础上,结合区域同时期的降水和径流资料,采用MIKE11软件中的UR-BAN模块构建流域降雨径流模型,以流域模拟流量和实测流量拟合效果最佳为原则,利于多场次的实测降水进行降雨径流的模拟分析,研究区域城市化发展对水文特性变化的影响。     

Kenya’s Secondary Cities Growth Strategy at a Crossroads: Which Way Forward?

Kenya has been promoting equitable urban and regional development since the 1970s despite the lack of a clearly formulated national urban policy or an urban and regional development policy. A key element of the country’s equitable urban and regional development effort is the promotion of secondary cities that would relieve population pressure in the countryside, help to better integrate the country’s rural and urban economies, help to reduce congestion and improve the quality of life in the metropolitan cities of Nairobi and Mombasa, and help increase the modernization spin-off which urban centers provide to the surrounding rural areas. Using recent census and economic survey data, this paper examines the current state of Kenya’s secondary cities in the context of its urban and regional development strategies. The paper finds that: (1) the country’s urban and regional development strategies have failed to work as planned largely because of insufficient devolution of power and fiscal responsibility to municipal and other local government units, (2) the country’s secondary cities are faced with immense challenges that undermine their ability to live up to expectations, (3) some of these cities have significantly grown economically over the last four decades despite immense challenges, and (4) Nairobi’s dominance of Kenya’s economy continues because of policies that unwittingly concentrate investments there. The paper concludes with strategies that could enhance the country’s urban and regional development programs and, in the process, aid the development of its secondary cities.     

Kenya’s Secondary Cities Growth Strategy at a Crossroads: Which Way Forward?

Kenya has been promoting equitable urban and regional development since the 1970s despite the lack of a clearly formulated national urban policy or an urban and regional development policy. A key element of the country’s equitable urban and regional development effort is the promotion of secondary cities that would relieve population pressure in the countryside, help to better integrate the country’s rural and urban economies, help to reduce congestion and improve the quality of life in the metropolitan cities of Nairobi and Mombasa, and help increase the modernization spin-off which urban centers provide to the surrounding rural areas. Using recent census and economic survey data, this paper examines the current state of Kenya’s secondary cities in the context of its urban and regional development strategies. The paper finds that: (1) the country’s urban and regional development strategies have failed to work as planned largely because of insufficient devolution of power and fiscal responsibility to municipal and other local government units, (2) the country’s secondary cities are faced with immense challenges that undermine their ability to live up to expectations, (3) some of these cities have significantly grown economically over the last four decades despite immense challenges, and (4) Nairobi’s dominance of Kenya’s economy continues because of policies that unwittingly concentrate investments there. The paper concludes with strategies that could enhance the country’s urban and regional development programs and, in the process, aid the development of its secondary cities.     

Globalisation and regional integration: the case of the Italian urban system

A recent study on the European integration of the Italian urban system shows that globalisation processes do not necessarily separate cities from their regional networks. The most successful cases of recent urban development in Italy are associated with the formation of metropolitan networked regions in which a major metropolitan centre is linked with cities of a lower level by hierarchical, complementary and synergetic relations. The paper examines the result of an analysis carried out on 148 major Italian daily urban systems. It takes into account two sets of indicators: one referring to the supraregional network interactions, measuring the degree of globalisation, and one referring to the proximity interactions inside the regional networks, measuring the degree of regional cohesion. They allow the definition of typologies of urban systems founded on a (normally positive) correlation between supraregional functional openness and regional integration.     

基于砂槽模型研究不同水流密度下盆地地下水流系统

在干旱半干旱地区,沉积盆地是人类生产、生活用水的主要载体,为查明在水流自身密度改变条件下盆地地下水流系统的变化特征,需在变密度条件下对盆地地下水流系统进行模拟研究。本文采用砂槽物理模型,在改变区域性水流密度条件下模拟研究地下水流系统的变化规律。试验结果显示:随着区域性水流密度的增加,区域水流系统的渗流速度和循环量均减少,且流线径流距离和径流深度也随之减小;而局部水流系统的渗流速度和循环量均增加。结果表明区域性水流密度的增加会抑制区域水流系统的发育,对局部水流系统有一定增强作用。本研究着重强调了区域性水流自身密度变化对盆地地下水流系统所产生的影响,并通过物理试验模拟得出在改变区域性水流密度条件下盆地地下水流系统的变化规律。     

北京城市洪涝问题与成因分析

利用社会经济统计数据和水文气象资料,探讨城市化背景下北京城市洪涝特征、形成机制及影响因素。近50年来城市内涝逐渐成为北京洪涝灾害的主要类型,随着城市化迅猛发展,城市内涝积水点数量在时间上表现为显著增加趋势,在空间上呈现出由内环逐步向外环扩张趋势,与城市化发展空间格局关系密切。从水循环的角度分析城市洪涝形成机制,指出区域气候变化和城市化发展改变了城市降水格局,汛期降水量和极端降水事件呈现下降趋势,但城区短历时强降水事件呈现增加态势;城市化发展改变了区域下垫面条件、城市流域产汇流特性和城市排水格局,进而影响了区域水循环过程和水量分配,在一定程度上增加了城市洪涝灾害风险;同时城市基础设施建设水平不足、排水排涝标准偏低、应急管理能力不足等因素,导致城市洪涝发生风险增加,降低了城市洪涝综合应对能力。     

西北干旱区城市土地利用变化及其区域生态环境效应——以甘肃河西地区为例

基于高分辨率土地利用/土地覆盖数据,本文对1985～2000年期间河西地区城市土地利用变化的区域生态环境效应进行了定量分析,结果表明:1)1985～2000年期间河西地区总体生态环境质量在一定程度上维持着相对稳定,但生态环境质量改善和恶化的两种趋势并存,并在县级行政单元上表现出明显的区域分异特征,城市用地变化对区域生态环境的影响总体而言不显著;2)整个河西地区城市用地增长缓慢,表明其城市化进程缓慢.与城市用地变化有关的土地利用类型也多分布在金昌、嘉峪关、张掖、武威和酒泉5个地级市所在地区,表明这些区域的城市化过程相对活跃;3)城市用地变化对生态环境影响的空间规律表现为:使生态环境原本较差的地区生态环境质量有所增加,而使生态环境质量较好的地区生态环境质量降低;4)城镇用地与工矿用地对区域生态环境的影响表现出与城市用地总体基本一致的规律,但农村居民点则对生态环境正、负两方面影响都较为显著;5)城市用地扩展对区域生态环境的影响也体现出与城市用地总体类似的区域分异特征;而城市用地收缩的影响则与此趋势相反.     

Imagining resilience: situating perceptions and emotions about climate change on Kamchatka, Russia

Global environmental change shapes places and people through ongoing transformation of ecological, socioeconomic, political, and cultural phenomena. One region construed as highly vulnerable to global environmental change, particularly anthropogenic climate change, is the North. Recent research about human communities in Western arctic and subarctic places revolve around vulnerability to anthropogenic climate change, focusing on loss of the ability to pursue traditional livelihoods, threats to ecosystems sustaining human communities and the need to adapt to new environmental regimes. Fewer studies address Russia and the perceptions and emotions related to climate change. To understand how people of the Russian North engage with climate change, I conducted ethnographic research in two rural and remote communities in subarctic alpine Kamchatka, Russia in 2009–2010. Local narratives about climate change largely reflect climate skepticism, and anthropogenic climate change is rejected as explaining environmental changes because: (1) climate is considered as naturally and cyclically changing, (2) humans are not considered a large enough force to alter natural climate cycles, (3) environmental problems are solvable with technology and (4) there is a lack of knowledge about climate change science. Thus, perceptions and emotions about transformation focus on other realms—socioeconomic, political, cultural—that are perceived as more critical to everyday life in the present and near future. Here, I describe these narratives and place the regional understanding of climate change in greater context to explain resistance to imagining environmental transformations due to climate change.     

SOVETSKAYA GEOLOGIYA (SOVIET GEOLOGY) IN COVER-TO-COVER TRANSLATION, 1961, NO. 8

In the Minusinsk (Siberia) intermontane downwarp, the Devonian-Carboniferous boundary lies within the regional paleomagnetic horizon. This boundary's perfect correlation with the same boundary in the Russian platform (4000 km away) is taken as evidence of the widespread occurrence of the inversely magnetized Upper Fammenian zone, of a certain isochronism between the Devonian-Carboniferous boundaries in Minusinsk and in the northwest of the Russian platform (notwithstanding their tectonic differences, etc.) and of possibilities of such correlations on a worldwide scale.--V.P. Sokoloff.     

北京城乡过渡区土地利用变化驱动力分析

在多时相遥感数据和实际调查数据的支持下，采用典型样带和样点相结合的研究方法，对北京西部城乡过渡区的土地利用/覆盖变化驱动力进行了研究。结果表明，研究区的土地利用/覆盖变化受到了不同层次、多种驱动力的综合作用，人类活动从整体上改变着城乡过渡区的景观特征，政策体制转变下的经济高速增长和快速的城市化过程是北京城乡过渡区土地利用/覆盖变化的根本原因。在这个过程中，城市投资和产业的转变与农村农业用地内部的结构调整相互结合，从城市和农村两个方向共同推动着北京城乡过渡区的土地利用/覆盖变化，而地形、交通等因素则从局部尺度上决定着土地利用/覆盖变化的方向。此外，人类个体的行为选择，尤其是就业和消费选择，也在一定程度上对北京城乡过渡区的土地利用/覆盖变化起着调整和修改作用。     

THE OCEAN-CONTINENT TRANSITION ZONES: STRATIGRAPHIC AND PALEOECOSYSTEM STUDIES

The author uses the Cenozoic of the Russian Pacific coast, drawing particularly on his 30-year experience with the molluscan faunas, as the source of examples of the ways that regional and global changes in the inorganic world affect the living world, as reflected in the stratigraphic and paleontologic record. The shelf ecosystem, despite its relative stability, shows periods of rapid change, reflecting both migration and accelerated evolution.     

区域土地利用变化驱动力研究前景展望

区域土地利用变化驱动力研究旨在从典型区域角度揭示土地利用变化背后的真正动因及其作用机理,进而动态模拟、预测区域土地利用变化过程。土地利用系统的自组织性及其内驱动因子作用的复杂性,决定了其研究必须与某一特定区域相联系,以便确定合适的可定量指标来体现外生驱动因子的驱动效果。系统地识别土地利用系统在不同控制状态下的驱动因子及其多种时空尺度效应,建立具有综合模拟的区域土地利用变化动态模型,能减少土地利用系统通常受临界值域和突变所左右的局面。区域土地利用变化驱动因子识别、区域土地利用变化驱动机制分析、区域土地利用变化驱动过程模拟等的研究现状表明,为更好地理解区域土地利用变化的机制和原因,测度现有及未来土地利用变化的速率、过程和地点,支持政府相关决策的制定与实施,促使区域土地利用变化向有利于人类的方向发展,区域土地利用变化驱动力分析应优先考虑以下研究领域：①驱动力因子识别及其作用效应的尺度依赖性;②驱动力因子的贡献量化及其在具体区域的非均一分布;③驱动力因子作用过程的自然反馈机制模型化。 [HT5H]关〓键〓词：[HT5K]     

The 1979 Census and some demographic trends in the Soviet Union

Recent demographic trends in the USSR are analyzed using preliminary 1979 census results that were published by the Soviet press in a central report issued on April 22, 1979, and in regional reports issued between April 25 and May 25, 1979. Topics discussed include regional patterns of change in the total population; urban and rural population; trends in the growth of major cities; changes in the sex ratio, particularly in urban areas; and trends in inter-regional and inter-republic migration.     

Future climate change impact evaluation on hydrologic processes in the Bharalu and Basistha basins using SWAT model

Urbanisation and climate change can have adverse effects on the streamflow and water balance components in river basins. This study focuses on the understanding of different hydrologic responses to climate change between urban and rural basins. The comprehensive semi-distributed hydrologic model, SWAT (Soil and Water Assessment Tool), is used to evaluate how the streamflow and water balance components vary under future climate change on Bharalu (urban basin) and Basistha (rural basin) River basins near the Brahmaputra River in India based on precipitation, temperature and geospatial data. Based on data collected in 1990–2012, it is found that 98.78% of the water yield generated for the urban Bharalu River basin is by surface runoff, comparing to 75% of that for the rural Basistha basin. Comparison of various hydrologic processes (e.g. precipitation, discharge, water yield, surface runoff, actual evapotranspiration and potential evapotranspiration) based on predicted climate change scenarios is evaluated. The urban Bharalu basin shows a decrease in streamflow, water yield, surface runoff, actual evapotranspiration in contrast to the rural Basistha basin, for the 2050s and 2090s decades. The average annual discharge will increase a maximum 1.43 and 2.20 m³/s from the base period for representative concentration pathways (RCPs) such as 2.6 and 8.5 pathways in Basistha River and it will decrease a maximum 0.67 and 0.46 m³/s for Bharalu River, respectively. This paper also discusses the influence of sensitive parameters on hydrologic processes, future issues and challenges in the rural and urban basins.     

Impact of city expansion on hydrological regime of Rispana Watershed,Dehradun, India

Rispana River flows through the heart of Dehradun, the capital city of Uttarakhand State, India. Uttarakhand had separated from Uttar Pradesh State in the year 2000; since then, Dehradun City has witnessed numerous changes. Both urban sprawl and densification were noticed, with around a 32% increase in population. The city had faced recurrent high runoff and urban flood situations in these last 2 decades. Therefore, the study was conducted to detect the change in land use/land cover (LULC), especially urbanization, through remote sensing data; and later to determine the impacts of such changes on the Rispana watershed hydrology. The LULC maps for the year 2003 and the 2017 were generated through supervised classification technique using the Landsat Series satellite datasets. The LULC change analysis depicted that mainly the urban settlement class increased with significant area among other classes from the year 2003–2017. It was noticed that majorly agriculture and fallow land (8.18 km², which is 13.52% of total watershed area) converted to urban, increasing the impervious area. Almost all the municipal wards, falling in the Rispana watershed, showed urbanization during the said period, with an increase of as high as 71%. The change in LULC or effect of urbanization on the hydrological response of the watershed was assessed using the most widely used Natural Resources Conservation Services Curve Number method. It was noticed that the area under moderated runoff potential (approx. 10.23 km²) steeply increased during the lean season, whereas, high runoff potential zones (5 km²) increased significantly under wet season. Therefore, it was concluded that an increase in impervious surface resulted in high runoff generation. Further, such LULC change along with climate might lead to high runoff within the watershed, which the present storm drainage network could not withstand. The situation generally led to urban floods and affected urban dwellers regularly. Therefore, it is critical to assess the hydrological impacts of LULC change for land use planning and water resource management. Furthermore, under the smart city project, the local government has various plans to improve present infrastructure; therefore, it becomes necessary to incorporate such observations in the policies.

     

Urban expanding pattern and soil organic, inorganic carbon distribution in Shanghai, China

Soil carbon stock changes induced by land-use change play an essential role in the global greenhouse effect and carbon circulation. This paper studies the urban expanding patterns and spatial characteristics of soil organic carbon (SOC) and soil inorganic carbon (SIC) distribution and evolution during the urbanization process of Shanghai, China, based on the data of the regional geochemical survey. Urbanization process in Shanghai, China, has been quickening greatly since the 1980s. The urban area expanded from 193.08 km² in 1980 to 1,570.52 km² in 2005, or up from 3.05 to 24.77% in the past 25 years, and the urban expansion circled the central city region according to the RS images acquired in the periods of 1980, 2000 and 2005. The urban topsoil is slightly enriched with SOC and SIC, which shows obvious spatial variability. By comparison of SOC and SIC distribution in the central urban area, urbanized area during 1980–2000, 2000–2005 and the suburban area, the SOC obviously accumulates in the central urban area, while SOC density in the urbanized area decreases; similarly, the SIC obviously accumulates in central urban area; furthermore, the SIC density increases with urban land use duration extending and urban ecosystem evolving. This paper provides the characteristics of SOC and SIC distribution and evolution during the course of urbanization, which may be useful for assessing the impact of land use and urban development on SOC and SIC pools in urban ecosystem.     

Blending in for a life less ordinary? Off the beaten track tourism experiences in the global city

Cities worldwide are becoming tourism destinations and tourism is at the centre of urban economic production built around networks and connections. Attractions within the city are driving regional economies. However, there is little information about the practices of the city by tourists and residents and how they change the understanding of the place as city and destination. Research still focus on reasons for tourists to be attracted to a city and their impacts. Yet, how this infusion is conceptualized in the touristified city remains unanswered. The objective of this paper is to conceptualize specific tourism trends in the urban context, where boundaries are becoming less visible and where network hospitality is an enabler of urban infusion. This concept paper is structured to correspond with the research propositions, an investigation of the infusion in the global city.     

基于时间序列建模的城市热岛时间尺度成分分离方法与应用

城市热岛效应是全球与区域气候变化研究中的焦点问题。基于2001—2012年较长时间序列的北京市MODIS地表温度产品及相关NDVI和反射率产品,给出地表温度时间序列构建方法。基于站点气象观测资料进行的精度验证表明地表温度时间序列构建方法可行,并最终给出城市热岛强度的量化方案。研究选取统计学中X-11-ARIMA时间序列建模方法,分离并分析城市热岛强度时间序列的结构性成分。分析发现,以平均城乡温差为指标的北京城市热岛强度季节性特征明显,与城乡土地利用状况、季节性地表覆盖、地物热特性以及气候因子等联系密切。趋势—循环特征与城市扩张速度及入选城市区域面积相关。以已发生城市热岛区域城乡平均温差为指标的北京城市热岛强度趋势—循环特性在12年间表现平稳。时间序列建模分析提取出不规则变动成分,为定量研究偶然因素对城市热岛的影响提供了可能。     

快速城市化地区多尺度水文观测试验与暴雨洪水响应机理分析

城市下垫面改变引起水文循环过程发生变异,导致目前已掌握的天然情况下的产汇流规律和机制难以解释城市化等新形势下的水文现象与过程,而面临需重新再认识的挑战。本文以长三角地区为典型,建立了不同城市化水平及空间规模的水文试验流域,探讨了快速城市化地区暴雨洪水响应规律和机制。结果表明：(1)不同量级降水事件下城镇用地土壤水响应程度(表层土壤水涨幅基本超过4%)总体高于其他土地利用类型,城市化地区下垫面的改变通过影响土壤水动态响应模式直接影响了地表产流过程,植被覆盖率较低的城镇用地和荒地土壤含水率呈现出陡涨陡落现象,而植被作用下的土地利用类型则表现出缓慢上升和缓慢消退的土壤水响应过程。(2)流域洪峰滞时和洪峰流量整体表现为随流域面积增加而呈幂律函数关系形式的增加。(3)总降水量与主要洪水特征(如洪峰流量、单位面积洪峰流量和径流深)基本呈显著相关(相关系数分别达0.49、0.41和0.78以上)。城市下垫面通过改变土壤水动态响应等产汇流特征而直接影响了洪水过程,未来长三角地区暴雨洪水在城市化和气候因素双重作用下呈现持续加剧的趋势。