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1.
Rural urban migration can often result in decreased agricultural output in countries with scarce land resources. It also can hasten the socio-economic problems associated with the overcrowded cities of the developing world. As only 10% of Iran is arable it is particularly vulnerable to threats to food security and self-sufficiency. This paper examines the daily flow of villagers to a major city near the vital staple crop producing rural district of Lakan, where out-migration is already occurring. Although most discussions of daily travel to cities is typically relegated to commuting, this paper aims to analyze travel for the purpose of access to a variety of facilities and services that villages in the rural district of Lakan lack including secondary schools, post offices, banks, and even telephones and newspaper stands. The paper emphasizes that daily journeys make permanent moves to the city more likely because of the major inconvenience that results from the scarcity of basic facilities within Lakan villages. Travel to a distant city for staple foods at grocery stores or for access to secondary schools, for example, could intensify future out-migration because the heavy inconvenience of constant travel might eventually outweigh the benefits of maintaining residency in villages. The paper utilizes information about daily travel to Rasht to recommend various government construction projects and initiatives to improve the quality of life for villagers and avert future rural–urban migration and the reduction in staple crop production that might result.  相似文献   

2.
Evaluation of groundwater resources in dry areas without enough data is a challenging task in many parts of the world, including Tehran–Karaj plain in Iran, which includes Tehran, the capital city of Iran and Karaj, one of Iran’s biggest cities. Water demand due to increasing agricultural and industrial activities caused many problems in the field of water resources management. In this study, the potential of groundwater resources was evaluated using remote sensing, geographic information system (GIS), and analytic hierarchy process (AHP) for the first time. Digital Elevation Model from Shuttle Radar Topography Mission was used to generate a slope map and drainage density map. Three Landsat-8 satellite images were utilized to provide lineament density and land cover/land use maps. Geological and soil type maps were provided from the Geological Survey and Mineral Explorations of Iran (GSI). Tropical Rainfall Measuring Mission data were used to prepare average annual precipitation map. Discharge values from 102 pumping wells in the time period of 2002–2014 were used to evaluate the results. Seven data layers were prepared, and the geodatabase was made in GIS. The layers and their classes were assigned weights using AHP method. Finally, the layers were overlaid based on their weights, and the potential map of groundwater resources was generated. The area was classified into five zones with very high, high, moderate, low, and very low potentials. The zones covered 5.95, 32.90, 22.70, 10.20, and 28.25% of the study area, respectively. The results showed good agreement with the field data obtained from discharge wells.  相似文献   

3.
社会资本定量评价方法及应用——以黑河流域为例   总被引：4，自引：0，他引：4  
李玉文  徐中民 《冰川冻土》2007,29(5):830-836
社会资本是促使人们参加集体活动的规范、网络和社会制度.参考国际上社会资本定量评价方法,利用问卷调查的形式,通过构造认知型社会资本和结构型社会资本相结合的社会资本指数,对黑河流域各地区微观水平的社会资本作了相对评价.黑河流域社会资本整体水平不高,只有7%乡镇的社会资本指数在80以上的,32%的乡镇在50~80之间,61%的乡镇在50以下.整体上黑河流域社会资本水平上游高于中下游,认知型社会资本高于结构型社会资本,城市社会资本水平高于农村,经济条件好的地方社会资本水平高于经济条件差的地方.研究为进一步探讨水资源社会化管理奠定了基础.  相似文献   

4.
The aim of this paper is to develop a methodology for identifying various dimensions of the spatial configuration of urban systems in Iran from an interaction perspective. Through the provision of empirical evidence of different types of flows of people including air passenger flows, passenger flows by bus and car, this paper compares the resulting spatial constellations of these flows through the innovative use of indices to systematically describe and measure five dimensions of an urban system’s spatial configuration that include: (1) centrality and dominance of vertices, (2) network cohesion, (3) network strength, (4) network symmetry, and (5) communities and levels. The findings show that although the spatial configurations of different flows are not the same, all were characterized by having a significant distance within a polycentric urban system due to the primacy of the Tehran metropolis. In regard to passenger flows by car and bus, it was found that for various functional regions, there was a balanced distribution of centrality and urban hierarchy evident in Iran. By contrast, air passenger flows were not able to determine centrality within a national urban hierarchy because of the limited distribution of centers for air travel in Iran at higher levels of spatial organization.  相似文献   

5.
Iran has been seeking to develop fully functional waste management strategies to address the problem of its rapidly growing cities. This requires proper evaluation to determine the most appropriate strategies to meet the goals of sustainable waste management. Environmental Impact Assessment is capable of contributing towards this goal. However, such assessments tend to involve a qualitative approach in the evaluation of the sustainability or unsustainability of potential options. Therefore, a suitable quantitative approach to evaluate sustainability/unsustainability is necessary. The paper applies a mathematical model to evaluate the sustainability of unmitigated options for a municipal solid waste disposal site in Tabriz, Iran. This was based upon rapid impact assessment matrix evaluation of the options. The model’s application determines whether the options are sustainable or unsustainable. The model application results indicate that all of the options were considered as unsustainable in an unmitigated state. The results for Tabriz were then compared and contrasted with results obtained by the authors for another MSW disposal site near Tehran. Based on this, there are questions as to the potential value of current waste management strategies. The paper concludes by stating that economic costs are the largest single barrier to achieving sustainable waste management. Furthermore, it is important to develop solutions which disposes and manages waste in a manner conducive to the long-term sustainability of the environment–human relationship.  相似文献   

6.
In this study analytical hierarchy process approach which uses expert’s knowledge, was applied for selection of the best wastewater treatment alternative for electroplating workshops, located in Tehran province, Iran. This method can be applied for complicated multi-criteria decision making to obtain scientific and reasonable results. Four wastewater treatment alternatives including reverse osmosis, nano filtration, ion exchange, and chemical precipitation were evaluated and ranked based on economical, technical, environmental/ social aspects. Each criterion includes different indices such as land area, capital cost, sludge disposal issues, operating and maintenance, local suppliers and warranty, system flexibility, required skilled and non skilled man power safety, and etc. The results showed that reverse osmosis achieved the maximum general profits and can be the best choice. Sensitivity analysis can shows the effect of inputs parameters change on the results. Sensitivity analysis was applied for each criterion. The results illustrated that for economic and technical criterion, chemical precipitation and for environment criterion, reverse osmosis were qualified.  相似文献   

7.
Paul Claval 《GeoJournal》2000,51(1-2):73-81
Capital cities reflect the nature and organization of the states they control. Their functional role is higher in centralized systems, societies where the state is the source of all legitimacy, and countries using Continental Law. It is lower in federal systems, pillarized societies and countries, which are ruled according to a Common Law. The symbolic status of capital cities is higher when the state is the source of all legitimacy, lower in consociationalist societies. Theses processes were responsible for the development of two types of political capital cities and one type of economic and cultural capital cities during the nineteenth century. A partial standardization of the functions and statuses of capital cities occurred later. The European Union is neither a state nor a super-state since its main responsibilities are still in the economic field, it lacks a huge administrative bureaucracy and does not have definitive territorial limits. The European Union has officially three capital cities, Strasbourg, Luxembourg and Brussels. The really important one is Brussels. Its functions are nevertheless quite different from those of national capital cities during the first half of the twentieth century. European capital cities are thriving because most of them managed to become economic metropolises. The result is that the European Union has a complex and rapidly evolving system of capital cities.  相似文献   

8.
Building on recent criticisms within the literature on queer migration raised by Andrew Gorman-Murray and Nathaniel Lewis, the article explores ‘unconventional’ trajectories of queer migration: a Global North metropolitan area-Global North metropolitan area one and a Global North metropolitan area-Global North ordinary city one. Two very different migration patterns are analyzed: the movement of young queer ‘creative’ Italians from different metropolitan areas (Rome, Milan, Bologna, Catania, Naples, Padua and Turin) towards Berlin (Germany) and the relocation of young queers from the major Italian cities (Rome and Milan) towards ordinary/small size towns. Aimed at highlighting the complexity of material and immaterial factors leading the decision to migrate in times of crisis, austerity politics and increasing unemployment, the article introduces the role of welfare regimes in shaping migration’s choices. This way, queer migrants and their socio-economic status and possibilities find materially situated within national/local welfare regimes, thus challenging the teleological binarism of the ‘coming-out’ journey always presuming a rural/urban movement for queer subjects. Within such a framework, the ordinary/small size town can become a place for ‘outness’ and self-realization of queer migrants who create bridges and connections with the metropolitan areas, thus queering the provincial contexts.  相似文献   

9.
Natural Hazards - The present study was done to analyze and compare synoptic conditions during the most durable pollution and clean waves (MDPW and MDCW) in Tehran City (capital of Iran). For this...  相似文献   

10.
Xiaomei Ji 《GeoJournal》2018,83(2):381-397
Since the 1980s, toponymy studies in Western societies has shifted away from traditional to critical paradigm, which is focused on political and cultural conflicts involved in place-(re)naming. But Chinese toponymist has paid little attention to this turning. City-renaming for tourism promotion or place marketing and stakeholders’ resulting responses in the context of China’s special ideology and tourism flourish will be good materials for critical toponymy studies. By field observation and interpretation on online texts, this article outlined the space–time process of city-renaming practices and their effects both positive and negative on touristic matters such as destination and resources, outside tourists and local habitants as well as neighbourhood relationship, dissected the renaming process of two typical tourist cities and summarized the traits of tourism placename field (TPF) by focusing on stakeholders’ responses to city-renaming practices referring to Bourdieu’s Field Theory. It found that, appropriate renaming can improve cities’ popularity at low-cost and high-efficiency, inappropriate one may do harm to destination, resource, tourists, locals and neighbourhood relationship. There existed variant responses to official renaming-decisions owing to stakeholders’ various habitus and capital conditions . TPF in China was dominated by governmental hegemony and economic priorities, which is the determinant that other sorts of capital in toponyms should yield to economic capital. However, a head-on boycott launched by other stakeholders will occur if renaming causes their direct economic loss rather than be passive victims.  相似文献   

11.
Traditional models of urban development are no longer adequate to describe current metropolitan transformations. These are now at the centre of a debate concerning management and administration. In Italy, delays in resolving problems of urban and metropolitan government, despite the legal framework provided by Law 142/90, have weighed heavily on the larger urban areas of the country: Rome, Naples, Milan, which have not been able to tackle the issue of metropolitan government. Recent legislation, while not providing a pre-defined institutional solution, allows separate administrative districts to collectively establish metropolitan institutions of `variable geometry'. The Milan urban area is not one city, but a system of mutually-dependent cities, linked to each other and the rest of the world by a transport network still requiring much investment. The vitality of its economic structure (especially its small firms) is held back by seriously inadequate infrastructure and low external economic efficiency. The provincial capital may boast `historic centrality' but the most interesting potential for development is to be found on the periphery and in the administrative districts immediately surrounding it, in the recovery of derelict industrial areas and dormitory towns established in the 1950s and 1960s, especially to the north. Recovery of derelict areas, green areas, and better transport links within the urban area and with the outside world are the key elements in the reorganization of `Greater Milan'. In this situation of rapid transformation the most appropriate political strategies involve negotiated planning. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

12.
Time independent seismic hazard analysis in Alborz and surrounding area   总被引：1，自引：0，他引：1  
The Bayesian probability estimation seems to have efficiencies that make it suitable for calculating different parameters of seismicity. Generally this method is able to combine prior information on seismicity while at the same time including statistical uncertainty associated with the estimation of the parameters used to quantify seismicity, in addition to the probabilistic uncertainties associated with the inherent randomness of earthquake occurrence. In this article a time-independent Bayesian approach, which yields the probability that a certain cut-off magnitude will be exceeded at certain time intervals is examined for the region of Alborz, Iran, in order to consider the following consequences for the city of Tehran. This area is located within the Alpine-Himalayan active mountain belt. Many active faults affect the Alborz, most of which are parallel to the range and accommodate the present day oblique convergence across it. Tehran, the capital of Iran, with millions of inhabitants is located near the foothills of the southern Central Alborz. This region has been affected several times by historical and recent earthquakes that confirm the importance of seismic hazard assessment through it. As the first step in this study an updated earthquake catalog is compiled for the Alborz. Then, by assuming a Poisson distribution for the number of earthquakes which occur at a certain time interval, the probabilistic earthquake occurrence is computed by the Bayesian approach. The highest probabilities are found for zone AA and the lowest probabilities for zones KD and CA, meanwhile the overall probability is high.  相似文献   

13.
Solving the problem of waste is one of the central tasks of environmental protection. It is becoming increasingly difficult to find suitable sites that are acceptable to the public. Salt and salt formations have relevant properties to be utilizing as a repository for each kind of waste. The favourable properties of salt make rock salt highly suitable as a host rock, in particular for non-radioactive and radioactive wastes. Tehran and suburb as an industrial state require a waste reservoir. The Great Kavir (the largest salt desert in Iran) with more than 50 diapirs has surrounded the eastern and southern part of Tehran Province. The Qom and Garmsar basins are the nearest salt diapirs to Tehran province, and there are suitable repository for waste disposal. Great Kavir diapirs have been investigated as a case study based on surface and subsurface studies for its suitability to host a repository for various types of waste. The procedure should be based on field work for surface investigation and also include geophysical studies for subsurface investigations. This research work is presented in regard to site selection in the Central Iran Salt Basins for deposition of only certain types of waste. Results of this study will indicate if the Central Iran Salt Basins are appropriate place to deposit industrial wastes in the deep bedded salt.  相似文献   

14.
The North Qazvin region is a part of the Central Alborz Mountains in Iran and has experienced destructive earthquakes. This region is a popular and industrial zone near Tehran, capital of Iran. To identify the highest and lowest seismic hazard location and consequently the seismic zonation of this region, different parameters, such as topography, geology, tectonics and seismicity, have been focused. Accordingly, the north of Qazvin region can be divided into three subzones: western, eastern and southern. Seismic activity of the western zone is higher than the other ones and seismic potential of the eastern zone is higher than the other two zones. This zoning is also necessary for all seismic active areas to find the most dangerous zone.  相似文献   

15.
The present study reports on secondary school teacher’s environmental attitude in India and Iran. One thousand and four teachers were selected through the stratified random sampling technique from 103 secondary schools of Mysore city (India) and Tehran city (Iran). Subjects consisted of 505 male and 499 females. They were assessed using the Taj Environmental Attitude Scale (TEAS) developed by Hasseen Taj (2001). Results revealed that there are significant differences between Indian and Iranian teachers in their level of environmental attitude. Also there are significant differences between them in environmental attitude across and within two groups with regard to their gender. Also in overall, type of school management (Government and private) is not a factor, which can affect teachers environmental attitude.  相似文献   

16.
Determination of dust loading in the atmosphere is important not only from the public health point of view, but also for regional climate changes. The present study focuses on the characteristics of two major dust events for two urban areas in Iran, Kermanshah and Tehran, over the period of 4 years from 2006 to 2009. To detect extreme dust outbreaks, various datasets including synoptic data, dust concentration, reanalysis data and numerical results of WRF and HYSPLIT models were used. The weather maps demonstrate that for these events dusts are mainly generated when wind velocity is high and humidity is low in the lower troposphere and the region is under the influence of a thermal low. The event lasts until the atmospheric stability prevails and the surface wind speed weakens. The thermal low nature of the synoptic conditions of these major events is also responsible for deep boundary layer development with its thermals affecting the vertical dust flux over the region. Trajectory studies show that the dust events originated from deserts in Iraq and Syria and transported towards Iran. The main distinction between the two types of mobilizations seems to affect the dust concentrations in the Tehran urban area.  相似文献   

17.
Capital cities are politico-administrative centers. They are command centers, they symbolize authority and also the unit that is governed. Primarily they are capitals of states, but other governance systems may also have capitals. In the European context there are now regional capital cities and at least the concept of a European capital. Particularly on account of their symbolic function but also for the uses made of its appearance in political life, the cityscape of capital cities is an interesting topic for research. There are different types of capital cities in Europe that give rise to different cityscapes. Existing urban networks and types of political regime are important in this respect. Although cityscapes are pretty stable, they are differently perceived over time and uses made of them also change. A research agenda for this intersection of historical, cultural and political geography should concentrate on the evolution of these cityscapes, their perception and the uses made of them in the acting out of politics.  相似文献   

18.
Microseismicity in the region of Tehran   总被引：6，自引：0，他引：6  
We record and analyze small earthquakes around Tehran, Iran, using the permanent seismological network of the Institute of Geophysics of the University of Tehran and two temporary dense seismological networks installed for several weeks during 1999 and 2000. Regional seismicity is distributed throughout Central Alborz, extending from the Caspian Sea to the Iran Plain, with the highest level of activity east of Tehran related to the Mosha and to the Garmsar faults, which both dip northward and have had strong historical earthquakes. Our focal mechanisms, the first for these faults, confirm a left lateral strike slip motion.  相似文献   

19.
Naturally, there are different species of Culex mosquitoes in Iran. Culex pipiens complex is widespread in many parts of the country, specially in urban areas. In spite of this fact that Cx. pipiens species is the vector of some orboviruses and filariasis in many countries of the World, it does not have an important role in transmission of diseases in Iran. This species can easily reproduce in urban areas, due to the infection of surface waters and presence of sewage canals. The importance of Cx.pipiens for mankind is in fact, its biting and nuisance, specially at sleeping time. In this study, six types of current military uniforms of Iran’s army were treated by permethrin (0.125 mg. permethrin [AI]/cm2) and examined against the biting of natural population of Cx.pipiens in urban areas in Tehran. Eight volunteer were selected for this study. Six of them put on the treated uniforms and the other two of them wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights July 2004. There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The average number of biting among who wore untreated uniforms (control) was 2.14 mosquito biting/min/person (128.2/hr), While it was 0.23 (13.8/hr) for who wore treated uniforms. The percent protection of treated uniforms, in comparison with untreated ones, was about 89%. The protection percent of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results of species identification among captured mosquitoes of a field study showed that about 95% of them are of Cx.pipiens species, and protection of treated uniforms against them, was estimated 87%. Moreover, as an accompaning environmental consequence a significant reduction in mosquito’s density was seen.  相似文献   

20.
Herman Kok 《GeoJournal》1999,49(1):53-62
After the changes of 1989, urban-to-rural migration in Poland and Hungary remained stable compared to rural-to-urban migration. This was connected to a growing importance of suburbanisation around major Hungarian and Polish cities. Suburban areas around these cities are attracting increasing numbers of migrants from the major cities. Pollution and higher crime rates, as well as rising living costs and increasing uncertainties make many people to decide to leave the city for the surrounding countryside. Not only upper middle-class people move to the suburbs, but also lower status people, for whom life in the big city became too difficult. Long-distance migration from the cities to the rural areas is declining. Economic problems together with low employment opportunities prevent people from making such a move. Though the overall level of urban-to-rural migration did not change too much, this article shows the rapidly increasing importance of suburbanisation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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