Riyadh and its development

After World War II Saudi Arabia has experienced spectacular changes. Based on huge oil and gas revenues a particularly rapid growth of population and a spectacular urbanization took place. One of the most booming cities in the desert environment of the arabian peninsula is the Kingdoms capital city of Riyadh. With a built-up area of 3.5 km² only before 1950 the city's present-day expansion reaches more than 500 km². During the same period of time the population of Riyadh grew from less than 50,000 in 1945 to more than 1.4 Mio. in 1985. Such an explosive development can be documented best by a satellite image. In this paper the process of urbanization of Riyadh is presented by the interpretation of a MOMS image taken in 1984, documenting the geographic situation, urban structures, and the city's development.     

Population density pattern and change in the city of Riyadh,Saudi Arabia

"This paper examines and assesses the changes in the population density pattern in the city of Riyadh, the capital of Saudi Arabia where the city has undergone dramatic changes in its physical as well as its social structure. Analysis of data revealed a decline in population density at an exponential rate from the city center with variation between city sectors and zones. The city's rapid horizontal expansion and dispersal of population is the result of factors such as increases in city population and in size and number of single family dwellings, widening of streets, rise in income and residential mobility rates, mass use of automobiles, change in family size, zoning regulations, leapfrogging, and huge governmental city development projects."     

Precarious residence: Indigenous housing and the right to the city

Drawing on findings from a study of Indigenous housing in a regional Western Australian city, this paper examines the experiences of Indigenous peoples as a particular set of ‘right bearers’ within the right-to-the-city discourse. In settler-states, colonial discourses of absence, threat, and authenticity have informed policy frameworks that have militated against various Indigenous claims of belonging, rights, and aspiration in relation to urban places. Housing has been a representative domain of struggle in this respect. Consequently, today, Indigenous peoples have disproportionately high rates of dependence on more volatile and discriminatory forms of tenure than their non-Indigenous counterparts.The paper examines the incongruence between State aspirations to move (Indigenous) people along a housing continuum in urban environments, and the actual experiences of Indigenous urban residents, which fix discursively on barriers to such movements. It also traces the deleterious, displacing impacts for urban Indigenous households of the retreat of the State in its role as a landlord for the socio-economically disadvantaged, and in responding to market signals and particular sociological theses regarding poverty, with specific spatial logics. In so doing, we advance two interwoven arguments. First, we assert that Indigenous people face a unique precarity in the Australian urban housing system, which is a result of both colonial and racially discriminatory forces, and economically discriminating processes such as capital concentration and the commodification of land. Second, we contend that this precarity sets many Indigenous people on housing career trajectories that are antithetical to policy intentions.     

Warsaw under transformation: new tendencies in the housing market

The aim of this paper is to show how and in what sense the post-socialist transformation process has influenced the urban spatial structure of Warsaw with the help of empirical evidence dealing with housing. Therefore, the main focus of the study is the transformation of the housing market in the 1990s under social and economic restructuring process. The article comprises two parts: the first part involves the geographical development of the urban spatial structure within the context of housing market changes. In order to explain today's transformation, the system of socialist time is also discussed. In the second part emphasis is placed on the evidence of the transformation in urban space, dealing with new tendencies and challenging mechanisms in the housing market. The last period of transformation is also investigated in terms of changes in the urban space since housing is seen as an important factor of urban transformation. Hence, following the brief outline of historical development of the urban space housing market changes including the privatization of urban land is going to be the concern of the paper. The problems of the transformation and practical implementation of the privatization process are also discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Investigation of the weathering layer using seismic refraction and high-resolution seismic reflection methods, NE of Riyadh city

Five seismic refraction and five high-resolution seismic reflection (HRSR) profiles were carried out in northeastern part of Riyadh city to investigate depth of the weathering layer. Results obtained from seismic refraction survey reveal the depths of weathering layer at 12, 25, 17, 12, and 16?m, respectively. On the other hand, HRSR stack sections illustrate the depths of weathering layer at 14, 28, 20, 13, and 18?m, respectively. The weathering layer is composed of alluvial sediments and gravel, which is underlain by a sequence of limestone and dolomite layer. Seismic results from site no. 2 have been found to be in good agreement with lithological information reported from the adjacent water well. The HRSR data generally reveal better signal-to-noise ratio and enhanced resolution compared to the refraction data. Although, the HRSR data failed in achieving high-quality common midpoint (CMP) stacking profile at site no. 3, it provide an improved image of the subsurface features than the refraction data, recognizing it as a potential seismic technique.     

To the market and back: Housing policy and state housing in New Zealand

Housing policy in New Zealand has traditionally been characterised by significant market intervention in support of home ownership and a residual state housing rental sector. Within the context of dramatic social welfare reforms in the 1990s, a set of radical housing reforms was introduced that profoundly transformed the role of the state in the housing system. Key elements of the reforms included the creation of a profit-oriented company to manage state rentals, a move to market rents in the state sector and the introduction of an accommodation supplement. This paper examines the underlying rationale and impacts of the reforms focusing on issues of privatisation, tenant turnover, affordability and tenant protest. Having examined the ongoing problems engendered by these reforms the paper reviews more recent political and legislative reforms that were sought to reassert the state's traditional position within the New Zealand housing market. This revised version was published online in July 2006 with corrections to the Cover Date.     

天然褐铁矿的光电化学响应及对嗜酸性氧化亚铁硫杆菌生长的影响

通过对比实验研究了天然褐铁矿对嗜酸性氧化亚铁硫杆菌(A.f.)生长的影响.利用X射线衍射分析(XRD)确定实验中所用天然褐铁矿样品的主要物相为针铁矿和赤铁矿,紫外-可见漫反射光谱(UV-Vis DRS)和不同光照条件下的时间电流曲线表明天然褐铁矿在可见光下具有良好的光电化学响应.采用H型装置进行双室体系反应,设置了3组对比实验,结果显示A.f.在有光催化电子传入情况下生长较好,在96 h内细胞浓度增加了12倍,3组实验中Fe2+浓度的变化规律与A.f.的生长趋势相对应.由此揭示了天然褐铁矿促进A.f.生长的机制为:在光照作用下天然褐铁矿能产生光生电子-空穴对,光生空穴被电子供体(抗坏血酸)捕获,分离出的光生电子传入阴极室能够将Fe3+还原为Fe2+,实现Fe2+的电化学再生,提供充足的电子能量来源,促进细菌生长.     

Assessment of pollution sources in the southeastern of the Riyadh and its impact on the population/Saudi Arabia

The rapid growth of Riyadh—capital of Saudi Arabia—is pushing the area to more pollution and incentive for reorganization. The aim of this research is to assess air pollutants in southeast of Riyadh and detect opinion of the population about their environment. The assessment was done by analyzing 405 questionnaires, evaluating thermal band of Landsat 8, and spatial analyzing of particular matter and chemicals in 19 air samples by geostatistical tool in the ArcMap. Most of the inhabitants stated that they are suffering from bad odor, sewage leakage, and dust mainly from a cement factory. The thermal band of Landsat clarified the location of the pollution sources mainly the 1st industrial city, Yammama Cement Factory, and power plant in Farouq area. The ordinary kriging maps showed that the highest concentration of PM₁₀ (>403 μg/m³) lied to the northern and western side of the study area and caused a health issue to most inhabitants.     

Consumption preferences and environmental externalities: A hedonic analysis of the housing market in Guangzhou

The urban housing market of China has been transformed since the 1980s from a centrally-planned to a free-market system. This study aimed to (1) investigate the position of outdoor environmental quality in house-buyers’ preferences; (2) assess monetary values attributed to environmental externalities by the hedonic pricing method (HPM); and (3) test the applicability of HPM in China. The study area was Guangzhou, the major city of south China with a booming real-estate market. A questionnaire survey was conducted with households in new residences sold in 2004. The main buying motives were improving living quarters and floor area. Security concerns and a preference for high-rise buildings were somewhat unexpected. Good outdoor environment, including green space provision, proximity to parks, and views of green space and water, carried significant hedonic values. Differences between the submarkets of old and new towns were found; new town households expected apartments in high-rise blocks, exclusive residential land use, and views of green space, while old town households preferred proximity to shopping areas and workplaces, green space within the development and proximity to nearby parks. The findings could help to fine tune the developing housing market to match supply with demand in quality terms. Values accorded to environmental attributes could justify funding for urban green spaces and nature conservation. The study verified the applicability of HPM to the housing context in China.     

Geo-environmental effect of landfill site, southeast of Riyadh, Saudi Arabia

Landfilled wastes manifest slow decomposition, producing emanation of gases, and outflow of leachate. Waste mass shows various chemical reactions and complex evolutions that occur under the influence of natural agents, as rain and microorganisms. These reactions lead to biological, physical, and chemical transformations of wastes. The intensity of the phenomenon is related to the air and the humidity. These factors originate from the initial composition of the solid waste, the operating mode of the landfill, and the geological and hydrogeological conditions. Leachate is considered a major source of groundwater pollution. It has a complex nature; it typically contains high concentrations of chemical hazardous including heavy metals, chemical compounds that may severely pollute the environment. These challenges are faced all over the world by environment protection agencies and waste management bodies. The challenge differs according to the specific situation of the site, the climatic, environmental, and geological factors. The international literature is rich with studies in this concern. Each country or region of the world has its own legislation and laws governing waste management, e.g., the European Commission Legislation, the US Environmental Agency, and so forth. The main objective of this study is to shed light on the environmental consequences of a landfill site located in the southeast of Riyadh City, Saudi Arabia. It constitutes a peculiar case because of its situation, its exploitation mode, and nature of buried wastes. The study made use of satellite MSS, TM, ETM and SPOT image 2007, and Digital Elevation Model (DEM), respectively. Geological, morphological, hydrological, hydrochemical, and detailed drainage analyses were performed. Records of meteorological stations were also used in this study. The satellite images illustrate the evolution of the site through time since its start in the 1990s of the twentieth century. The main geological units outcropping in the area are the Sulaiy Formation, the Yamama Formation, Khabra deposits, floodplain deposits, alluvium, and sheet gravel. Drainage analyses shows a dendritic nature for the network, a total area of 2,113 km², basin slope of 0.016, perimeter of 430?×?10³, and a mean elevation of 635 m. Annual rainfall is around 100 mm, evapotranspiration is about 2,900 mm, wind speed averages at 5.1 km/h, and runoff peak is within 2.7–4.7 m³/s. A plume of total dissolved solids and nitrates was observed to initiate from the landfill site. Heavy metal concentration confirms the same result. Planners, environmentalists, decision makers, and other interest groups can use the findings of this study for environmental management of the landfill and protection of the downstream part of the Sulaiy tributary from leachate contamination. The results indicate the importance of monitoring landfills through the combined use of ground and satellite monitoring.     

Link of intensity of heat-island effect of a city with its size and population

Possibly the formation of the heat-island effect of cities (especially megapolises) is the most evident is consequence of man’s impact on the climatic regime. The intensity of the heat-island effect in a city, which is characterized by a surface air temperature drop between the urban core and its peripheral region, reaches several degrees. In this study, by means of power function, the model connecting the intensity of the heat-island effect in a city with the size of the population and/or city area is proposed. Qualitative model analysis, in comparison to the statistical data, allows us to allocate and classify various regimes of cities and their dynamics.     

The city of Tyre,Lebanon and its semi-artificial tombolo

The sedimentological history of the peninsular city of Tyre, located on the southern coast of Lebanon, reflects the political events surrounding Alexander the Great's conquest of the East (332 B.C.E.). Like many other Phoenician settlements, the city was originally situated on a small, relict rocky islet, but was later connected to the mainland by an artificial causeway constructed by Alexander's troops. As a result of the causeway construction, a gigantic tombolo formed, composed of at least 10 million m³ of sediment, mostly sand. Calculations based on the present size of the land tombolo of Tyre show that the average regional yearly volume of sand drift from the south and the north for the past 2300 years was approximately 4000 m³. If the present composition of high carbonate tombolo sands is representative of the entire sand body of the tombolo, about two thirds of the mass originates from nearby beaches which formed as a result of the erosion of the Pleistocene carbonate sandstone known as “Hajar Ramli.” © 1996 John Wiley & Sons, Inc.     

The city and its port—an economic appraisal

Following a brief examination of the role of ports as foci for industrial and urban development, this paper discusses four major changes—the scale of international trade, structural changes in port activities, port industrialization, and traffic origin and destination—which are acting to alter the relationship between ports and their urban areas. Attention is then focused on the redevelopment of docklands and the need to inform public and political opinion of the importance of port activities to the development of local, regional and national economies. The use of economic impact studies to highlight the multiplier effects of port activities is discussed.     

珠江三角洲海岸变迁及对城市可持续发展的影响

应用遥感技术,结合2003年野外实地调查,利用地理信息系统(GIS)将历史时期海岸线叠加处理,得出珠江三角洲最新岸线演变动态.论文回顾了历史时期珠江三角洲的发育演变,对珠江三角洲自1965至2003年38年间围垦土地增长速率和海岸线变化趋势作了定量分析和测算,认为珠江三角洲海岸演进呈越来越快的趋势,其中伶仃洋、磨刀门、黄茅海为海岸变迁的典型地段.以珠江口地区为重点对河口海岸演变的作用效应、人类活动特点及其引发的海岸环境地质问题、海平面上升对环境的叠加影响等进行了分析,论述了海岸异常变迁背景下,人类工程活动造成湿地破坏、水位壅高、航道淤积、污水滞留等不良环境地质问题.海平面上升造成珠江三角洲大片低地被淹没、风暴潮灾害加剧等,对城市可持续发展的形势影响巨大.     

Excavating Lefebvre: The right to the city and its urban politics of the inhabitant

Much current activism and scholarship has raised concern that the various processes of neoliberal restructuring are threatening democracy. More specifically, researchers in geography and other social sciences have stressed that political and economic restructuring in cities is negatively affecting the enfranchisement of urban residents. Much recent research and writing has explored progressive responses to this perceived disenfranchisement in cities. One popular trend has been a fascination with the idea of the `right to the city' as a way to respond to neoliberal urbanism and better empower urban dwellers. I argue that the right to the city holds promise, but that in the literature the idea remains both theoretically and politically underdeveloped. It remains unclear (1) what the right to the city entails or (2) how it might address current problems of disenfranchisement. This paper examines the right to the city in greater depth. It does so by offering a close reading and analysis of the intellectual roots of the idea: the writings of Henri Lefebvre. I suggest that Lefebvre's right to the city is more radical, more problematic, and more indeterminate than the current literature makes it seem. The paper concludes by suggesting that the right to the city does offer distinct potential for resisting current threats to urban enfranchisement. However, the right to the city is not a panacea. It must be seen not as a completed solution to current problems, but as an opening to a new urban politics, what I call an urban politics of the inhabitant.     

落实调控措施强化政府责任构建和完善城镇住房保障体系

近年来，任建设部的指导和省委、省政府的高度重视下，我省认真贯彻落实国家的宏观调控政策措施，保持房地产市场平稳运行，充分发挥其满足住房消费、提高居民居住水平的基础性作用。同时，切实强化政府责任，大力加强住房保障，不断改善中低收入家庭住房条件，取得一定的成效。至今年年底，全省所有市、县基本上建立了经济适用住房制度，解决将近20万户中低收入家庭的仕房困难。有57个市、县实施廉租住房制度，覆盖率达到82．6％，惠及1万个以上家庭。全省参加住房公积金制。     

Opportunities accruing from the application of public private partnerships in down market urban housing in Kenya

GeoJournal - The purpose of this study was to investigate the opportunities which accrue from application of PPPs in development of down market urban housing in Kenya, hence attracting private...