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1.
This paper examines the distribution characteristics of urban settlements in the Kingdom of Saudi Arabia through major dimensions such as settlement regularly, degree of primacy and polarisation at the national and geographic regional levels. The paper points out that the settlement pattern at the national level has transformed from a primate distribution during the pre-plan period (< 1970) to an intermediary distribution during the period of development planning (1970 >). At the geographical regional level the settlement distribution, however, has shown diverse pattern. While the regional settlement distribution of Western and Eastern Region have shown trends of increasing polarisation, settlements in the Northern and Southern Regions are more log-normal in character. This is explained by the increasing growth of small and intermediary towns in the Northern and Southern Regions. The paper concludes that the national trend of decreasing urban primacy, induced by the decentralised national development strategies, is less pronounced due to the absence of a balanced regional investment policy. Since the government expenditure and settlement population growth rates are not related, slow growing primate cities continue to receive a larger share of public expenditure, enabling them to retain their primacy. This calls for a balanced regional investment policy to fully realise the national strategy of regional balance and multi-polar settlement pattern.  相似文献   

2.
Rural settlements,mission settlements and rehabilitation in Transkei   总被引:1,自引:0,他引:1  
During the 19th century the predominant form of rural settlement in Transkei was that of dispersed homesteads. The form of the homesteads tended to differ from tribe to tribe, while the homesteads of various tribal groups were separated from each other by uninhabitated areas, or buffer zones. During the 19th century mission settlements were introduced to Transkei, some of which developed into towns.In the 20th century, mainly as a result of government action, homesteads have been nucleated into rural settlements and villages and much of the land has been fenced. A few peri-urban and industrial villages also exist in Transkei. Over 95% of the population of Transkei in 1980 were still rural dwellers.  相似文献   

3.
Living resources in estuarine systems have been so intensively harvested that many fisheries are severely depleted at a time when demand for these resources is rising. In addition, multiple use demands on estuaries often conflict, leaving unresolved management questions. With the movement of the population to the coastal regions, conflicts among uses and users of estuarine resources are increasing. Aquaculture offers one means to reconcile the conflicting demands for use of the estuarine resource. Yet, the nation has few, if any new policy or management approaches to address these conflicts. Management on the level of the watershed is one effective tool that should be more effectively used. Involvement of the full range of stakeholders or user groups in policy setting and management options has brought remarkable success in a small number of cases where this approach has been used. The nation will need to develop other tools and approaches if estuaries are to be restored and protected as protected as planned in federal, regional, and state laws and initiatives.  相似文献   

4.
Informal settlements are an important source of affordable housing and economic activity in developing cities. Research shows that informal settlements are at high risk from natural hazards and the effects of global climate change. Conditions within such settlements are diverse, however, and it is important that we understand the variation in risk across households. In this paper, we study the uneven terrain of risk to localized hazards in informal settlements in Kolkata, India. Our research question is, which factors predict household exposure to monsoon rain hazards? We surveyed 414 households living in low-lying informal settlements on the city’s periphery. Using a variety of predictors, we estimate binary logistic models for two outcome variables tied to monsoon rain: home flooding and home leaking. We find that household exposure varies significantly across our study population and follows predictable patterns based on socio-economic and infrastructure variables. The home flooding model results show that households with higher incomes are less likely to flood, but in situ births increase exposure. Households living in structures made of more permanent materials are less likely to flood, as are households living near infrastructure. The home leaking model shows that households with relative financial stability are less likely to leak, as are those that have been living in the settlement for longer periods of time and whose houses are made of better quality materials. These findings indicate that extensive risk in informal settlements is unevenly experienced and that policies intended to reduce disaster and climate risk should focus on the lowest-income households, the provision of infrastructure, and security of tenure.  相似文献   

5.
Flood risk assessment for informal settlements   总被引:3,自引:2,他引:1  
The urban informal settlements are particularly vulnerable to flooding events, due to both their generally poor quality of construction and high population density. An integrated approach to the analysis of flooding risk of informal settlements should take into account, and propagate, the many sources of uncertainty affecting the problem, ranging from the characterization of rainfall curve and flooding hazard to the characterization of the vulnerability of the portfolio of buildings. This paper proposes a probabilistic and modular approach for calculating the flooding risk in terms of the mean annual frequency of exceeding a specific limit state for each building within the informal settlement and the expected number of people affected (if the area is not evacuated). The flooding risk in this approach is calculated by the convolution of flooding hazard and flooding fragility for a specified limit state for each structure within the portfolio of buildings. This is achieved by employing the flooding height as an intermediate variable bridging over the fragility and hazard calculations. The focus of this paper is on an ultimate limit state where the life of slum dwellers is endangered by flooding. The fragility is calculated by using a logic tree procedure where several possible combinations of building features/construction details, and their eventual outcome in terms of the necessity to perform structural analysis or the application of nominal threshold flood heights, are taken into account. The logic tree branch probabilities are characterized based on both the orthophoto recognition and the sample in situ building survey. The application of the methodology is presented for Suna, a sub-ward of Dar es Salaam City (Tanzania) in the Msimbazi River basin having a high concentration of informal settlements.  相似文献   

6.
The global extraction of minerals is commonly located in areas populated by indigenous people; and while conflicts between multinational corporations and local activists and indigenous people are widespread today, the understanding of their dynamics are lacking. The Swedish government’s encouragement to an expanding mining industry has caused resistance due to environmental and social implications, particularly its effect on Sámi reindeer husbandry. The resistance to a mine in Gállok is based on the belief that the right to decide about land use historically falls on the Sámi people, and the right to affect land use is detrimental for the survival of Sámi culture and reindeer husbandry. Although the conflict may be perceived as concerning access to natural resources, we argue that the perceived environmental conflict can be viewed as part of a larger struggle over social status and recognition. Data have been collected using qualitative methods such as observations, interviews and documents. The subsequent analysis relies on a meta-theoretical framework of justice as recognition using a typology of relations of power. Our findings suggest that relations of power constitute different categories of social actors. Stakeholders like the Sámi population are subordinated to more dominant stakeholders such as the government, the company and media, who have ‘more’ power or ‘different’ kinds of power ‘over’ others. Through these asymmetric power relations, historical state-Sámi relations are continuously reproduced within prevailing institutions, and also in this mining conflict. Interviewees from business and the municipality testified to the discourses driven by a neoliberal and profit-focused worldview. Challenging the neoliberal discourse, other stakeholders, namely civil society and Sámi, expressed an alternative discourse based on a local, traditional, cultural, environmental and anti-neoliberal worldview.  相似文献   

7.
The paper describes spatially the zonal movements of residents to three squatter settlements established at different time periods in Mexico City. In addition, moves are related to the dynamics of the low income housing system and previous theories of intra-city squatter migration behaviour are evaluated. The data corroborate the concept that the traditionally accepted pattern of centre to periphery, tenement to squatter settlement movements has altered. Direct movement into the periphery on the part of incoming migrants is increasingly important, and older established squatter areas are the most important suppliers of population in recent invasions. The implications for the distribution and structure of housing opportunities for future low-income populations in Mexico City are discussed.  相似文献   

8.
This paper investigates the increasing provision of ‘community benefits’ – i.e. financial or material benefits to communities affected by wind energy development – with a focus on on-shore wind projects in Wales. The paper argues that as community benefits are becoming more significant in scale, so pressures are mounting on what have hitherto been largely ad hoc arrangements for their disbursement. The paper finds that previously dominant definitions of communities as places directly affected by and within close proximity to wind farm development, are being challenged by the tendency to define ‘affected’ communities as broader entities characterised by more indirect and widely dispersed claims to benefit entitlement. This redefinition of the recipient community is causing conflict, much of it focused on debates about how community benefits should be governed. Evidence suggests that any re-scaling of relations around community benefits – from local compensation towards wider development goals – may be more consensually achieved in communities with previous experience in handling these funds, and where growing income streams allow multiple constituencies to be satisfied.  相似文献   

9.
Kenya is one of those African countries with a very high population pressure. In cultivatable areas we find up to 650 rural inhabitants per sq km. The search for new possibilities of agricultural settlement is an indispensable task. Many sciences are involved, also the geography of climates. Probably the largest potential settlement area from the climatic point of view is the Northern coastal zone. It has been settled in medieval times much more densely than today. War-like invasions of nomads have decreased the population since the 16th century. The average density of the cultivatable strip has been less than 5 inhabitants per sqkm in the last census year 1969. New settlement schemes have been developed since 1970, but they face the difficulty to choose the right varieties of crops. Careful climatic investigations are necessary for the further selection of areas and for the agricultural extension service. Here, only a first approach has been made. The main emphasis was laid on the effective rainfall in the so-called agrohumid period of the year and its probability. A new system of climatic classification was applied to give a frame for further, more specialised studies.  相似文献   

10.
In the last five decades, many informal communities in Accra, Ghana have suffered from annual flood hazards. Residents of these communities appear to have successfully resisted evictions by city authorities; survived flood hazards and poor environmental health conditions. These flood affected households continue to survive with increasing housing and population densities in the face of these annual floods. Are they becoming resilient? Have residents built adaptive capacities through learning experiences from previous flood occurrences and evictions attempts? What has produced and continued to shape their responses to flooding? What can be learned from this supposed grassroots resilience to inform flood management in urban Africa? Using case studies of three informal communities of Glefe, Agbogbloshie and Old Fadama, this paper explores the gradual and evolving adaptive capacities and social resilience to flood hazards among poor urban dwellers. The paper reveals the depth of understanding and embodied nature of flood experiences among affected slum dwellers and how these are gradually being transformed into adaptive capacities and shaping their responses. In the absence of efficient state flood interventions, there are emerging and enduring flood responses and adaptation practices shaped by residents’ social networks, political alliances and sense of place. These responses translates into continuous re-structuring of housing units, construction of communal drains, creation of local evacuation teams and safe havens. Urban policy contributions that can be learned from these emerging grassroots capacities for flood vulnerability management have been proposed.  相似文献   

11.
某基坑位移、沉降和内力实测结果及预警值讨论   总被引:8,自引:0,他引:8  
李俊  张小平 《岩土力学》2008,29(4):1045-1052
以某深基坑支护结构位移、沉降、内力及水位的施工监测数据为依据,探讨了位移、沉降与内力大小及变化规律。实测表明:支护桩及外侧土体各点随着基坑开挖深度和时间的递增,水平位移逐步增大,增大速度由快逐步趋于平稳。另外,位移大小还与周围建筑物位置和支撑条件有关。周围建筑物的沉降随时间增大,且离基坑越近则越大;立柱沉降及土的隆起量与承受的支撑重量及基坑形状有关;支撑轴力的大小及变化与地质条件、支撑刚度和施工开挖顺序及速度等因素有很大关系;桩身偏心较小,底部可按轴心受力计算。最后,对预警值进行了讨论。  相似文献   

12.
Michael Woods 《GeoJournal》2011,76(4):365-381
This paper examines the local politics through which the reconstitution of rural localities under globalization is advanced and contested, with particular reference to the impact of international amenity migration. It contends that as globalization proceeds not by domination but by hybridization and negotiation, local politics is critical as the sphere in which the outcomes of globalization processes are interpreted and contested. The paper examines the case study of Queenstown Lakes district in South Island, New Zealand, as a locality that has experienced significant transformation through engagement with globalization processes. These include high levels of international amenity in-migration, substantial overseas investment in property, commerce and construction projects, and an increasing volume of international tourists. Collectively, these processes have contributed to rapid population growth and intensive pressure for the development of rural land in the area. As detailed in the paper, land use planning became the dominant issue in local politics, with conflict between groups informed by ‘boosterist’ and ‘environmentalist’ stand-points, as well as the ‘aspirational ruralism’ of amenity in-migrants. Although locally-grounded, the conflict engaged trans-local actors and networks and transgressed space and scale, thus becoming itself an expression of globalization.  相似文献   

13.
The article describes a new form of transnational environmental conflict that developed in the wake of globalisation. Activist in this new type of conflict still act as proxies of groups under pressure but in contrast to transnational environmental conflicts hitherto the target of their protests is rather their own society at home than the location of the pressured group. Despite these conditions it is claimed that this type of metaphorical conflict is going to become more frequent as alliances are built along the oppostion to a dominant discourse. According to the model, conflicts of values are easier to transfer on stages abroad or across the Atlantic than conflicts of interests and motivation for activists is higher as the return is affecting their home society. Dynamic and features of this type of conflict are explained with help of discourse theory.  相似文献   

14.
基于遗传算法的软土地基沉降预测   总被引:8,自引:3,他引:5  
夏江  严平  庄一舟  许向明 《岩土力学》2004,25(7):1131-1134
基于自然进化原理的遗传算法是一种解决岩土工程复杂非线性问题十分有前景的方法。对遗传算法中一些具有代表性的算法作了简要分析和评论。软土地基沉降受众多因素的影响,在时序上表现出复杂的非线性特征。针对一个加固纠偏工程的沉降预测问题,运用MATLAB编写遗传算法程序进行了预测分析。计算结果与实测资料基本一致,它在全局优化、非线性优化、多参数优化等方面表现出了传统算法无法比拟的优势。  相似文献   

15.
Classifying urban land cover from high-resolution satellite imagery is challenging, and those challenges are compounded when the imagery databases are very large. Accurate land cover data is a crucial component of the population distribution modeling efforts of the Oak Ridge National Laboratory’s (ORNL) LandScan Program. Currently, LandScan Program imagery analysts manually interpret high-resolution (1–5 m) imagery to augment existing satellite-derived medium (30 m) and coarse (1 km) resolution land cover datasets. For LandScan, the high-resolution image archives that require interpretation are on the order of terabytes. The goal of this research is to automate human settlement mapping by utilizing ORNL’s high performance computing capabilities. Our algorithm employs gray-level and local edge-pattern co-occurrence matrices to generate texture and edge patterns. Areas of urban land cover correlate with statistical features derived from these texture and edge patterns. We have parallelized our algorithms for implementation on a 64-node system using a single instruction multiple data programming model (SIMD) with Message Passing Interface (MPI) as the communication mode. Our parallel-configured classifier performs 30–40 times faster than stand-alone alternatives. We have tested our system on IKONOS imagery. The early results are promising, pointing towards future large-scale classification of human settlements at high-resolution.  相似文献   

16.
The objective of this paper is to engage constructively with literature on armed conflict and resources in order to draw attention both to assumptions that hinder a more accurate or useful understanding of natural resources and their role in territorial conflict as well as to aspects of this field of research that merit further work. In much of the literature on resource conflict, territorial aspects are either implicitly or explicitly tied to resource conflict largely through the assumption that the value of territory is intrinsic. Little of the literature attempts to advance theory, specifically, either on the particular role of resources or on the meaning and objectives of conflict beyond a one-dimensional objective of maintaining or securing control of territory. The paper considers themes of resource scarcity and resource abundance in conflict. A third section focuses on an analysis both of natural resource databases and of conflict databases (both international and civil) which emphasizes problematic results of blending these databases to demonstrate correlations. UIUC territorial conflict management workshop  相似文献   

17.
Pierre Dansereau 《Geoforum》1978,9(3):161-210
This paper attempts to place within an ecological framework the way in which man has appropriated and changed landscape. The ecosystem concept is used in order to facilitate a realistic examination of the ever changing relationship of man and nature. The resultant ecological grading of human settlements covers the full range of environments from “wild” to “urban”. It is hoped that such an approach will help to alert, educate, and instruct planners and decision makers as to the ecological cost of a number of problems which are normally viewed in economic, political, or social terms.  相似文献   

18.
Gridded population distribution data are finding increasing use in a wide range of fields, including resource allocation, disease burden estimation and climate change impact assessment. Land cover information can be used in combination with detailed settlement extents to redistribute aggregated census counts to improve the accuracy of national-scale gridded population data. In East Africa, such analyses have been done using regional land cover data, thus restricting application of the approach to this region. If gridded population data are to be improved across Africa, an alternative, consistent and comparable source of land cover data is required. Here these analyses were repeated for Kenya using four continent-wide land cover datasets combined with detailed settlement extents and accuracies were assessed against detailed census data. The aim was to identify the large area land cover dataset that, combined with detailed settlement extents, produce the most accurate population distribution data. The effectiveness of the population distribution modelling procedures in the absence of high resolution census data was evaluated, as was the extrapolation ability of population densities between different regions. Results showed that the use of the GlobCover dataset refined with detailed settlement extents provided significantly more accurate gridded population data compared to the use of refined AVHRR-derived, MODIS-derived and GLC2000 land cover datasets. This study supports the hypothesis that land cover information is important for improving population distribution model accuracies, particularly in countries where only coarse resolution census data are available. Obtaining high resolution census data must however remain the priority. With its higher spatial resolution and its more recent data acquisition, the GlobCover dataset was found as the most valuable resource to use in combination with detailed settlement extents for the production of gridded population datasets across large areas.  相似文献   

19.
Although some scholars describe migrant farmers as ‘exceptional resource degraders’ others do not. This paper uses evidence from the transitional agro-ecological zone of Ghana, to examine whether there are substantial differences between households of migrants and the host population regarding agricultural land use. The aim is to determine whether migrants are more destructive of the land (and hence the environment) than the host population. This will be examined using a standard model of the determinants of agricultural land use, to which we add variables representing demographic impacts, including in-migration. The data used are from a household survey undertaken in 2002 among 110 migrant and 142 host population farming households in central Ghana. Results are mixed. We find no support for the hypothesis that households with migrants are less likely to consider the long-term effects of land use by increasing the land area in cultivation, but at the same time there is evidence of use of more land-intensive agricultural practices which tend to degrade farm land over time.  相似文献   

20.
Jörg Janzen 《Geoforum》1983,14(3):289-309
Sweeping changes have recently taken place in the life and economic circumstances of nomadic peoples in the countries of the Islamic East. In this respect, the ‘small’ oil-rich Gulf states are in a somewhat different position. In contrast to many other countries with nomadic populations, the prospects for the integration of the non-sedentary elements of the population into the process of modern development are more favourable in the Gulf states, chiefly because of their wealth in oil. The Omani government has devoted special attention to the development of the nomadic environment in the southern province of Dhofar following the end of the Dhofar conflict. A speedy expansion of the technological and social infrastructure took place on the basis of a newly created central place system of government centres. This covered the extension or provision of transport facilities, water supply, education, rural health services, religious establishments, the distribution of basic requisites to the population and the stimulation of retail trade. Additional government measures comprised the construction of low-cost housing for refugees, the allocation of building sites, financial assistance to the socially deprived and subsidies to shaykhs, as well as various small-scale programmes for the improvement of agriculture, livestock and fisheries. A further essential contribution to modern development has been the creation of thousands of new jobs, above all in the state's public service sector. The effects of the new opportunities for employment, together with relatively high cash incomes now available for many nomadic families, can be seen in numerous changes. The most important new trends can be summarised as the decline of the caravan trade, the advent of motor transport, an increasing rate of permanent settlement accompanied by a switch to gardening, the practice of commuting to fixed employment instead of nomadism, dependence on external food and outside markets and economic dependence on allowances, standardized tents and stone houses in place of the traditional dwellings. It can generally be confirmed that the nomadic population of Dhofar has shared in modern development in a variety of ways. However, a marked gap in development exists between the coastal area in the south with its settled population and the nomadic living space in the interior of Dhofar. Only the speedy introduction of a development programme that caters for the specific interests of the nomads can satisfactorily achieve their ultimate integration. If such measures fail to materialise one must fear a long-term social and economic decline for the majority of nomads in Dhofar and their reduction to a marginal status.  相似文献   

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