GEOGRAPHICAL RESEARCH
Year:2006 | Volume:21 | Issue:2 (81)|Papers Count:7

The major objective of this paper is to investigate the causes of survival as well as Sustaining ancient cities during social and natural events.This process could well be classified into three distinguished eras; i.e. the periods of "Iranian-city", "Islamic-city" and "Modem-city". Proposing some hypotheses as well as introducing major urban-sociological theories follow this article. It emphasizes Huffer's structural-positional and Bemat's civilized values theories regarding definition of a city. Furthermore, Asian production method, Dokolunj religious theory and Christaler central place theory were used to support its factual explanation. Longitudinal investigation of historical documents along with personal observation and secondary analysis of viable national and international reports were constituted the major methodological frame works.This article tries to evaluate the civilized values and function of those three periods upon flourishing, prosperity and rehabilitation of ancient cities. In addition, reproduction of spectacular information with regard to couple ancient and live cities located in eastern part of Iran including Zouzan, Salumak, Sangan and Khar Gerd are among some of the other pursuing objective of this study. It is argued that very little information has been released regarding some of their historic monuments.It is inferred that modem cities through removal of relevant historical and international obstacles and diffusion of western civilization values, could well evolved upon ancient cities' circuit. They could develop good perspectives through provision of new infrastructure.

The investigation of democracy variables as well as corresponding bottlenecks and obstacles within Islamic regions demonstrate that democracy would not be confined just to one specific culture such as west democracy and cultural liberalism. Rather it particularly demands surveying of religious and identified culture. In addition, fulfillment of democracy in Islamic world entails interdependent between democracy and human rights. That is, any drawbacks regarding the implementation of human rights would consider as a threat to democracy. Finally, at the beginning of 21 century, policy makers need to consider effective flexibility regarding new international trends, people's inspiration and realistic accounts of democracy in Islamic worlds.

Sand storm is being considered as one of the major natural disaster in world dry regions and deserts in general, and Iran-arid zone in particular.Ardakan-Yazd plain taking into consideration its geographical location from aridity stand point is being subjected to this phenomenaas well. This in turn, has led to considerable damages. Thus any study toward understanding their very nature, may reduce their destructive impacts.This paper aims to study this phenomenon by selecting 12 different sample storms.Level synoptic maps of the Earth and those associating with 850 and 500 hectopascal were used. Wind direction and velocity, horizontal vision, moisture, temperature, cloudiness, pressure and dust are the prime variables of the study. According to the finding of this study, in low dynamic pressure which accompanies cold front, vertical air movement may result in air instability and subsequent sand storms in the region. One may argue that passage or approaching of a trough accompanied by strong advection of cold air and pressure gradient, may cause sand storms as well.In addition, the existence of pressure gradient between this region and adjacent area could be proved as another reason regarding sand storm event. In the area under consideration, most of the storms and high velocity would blow from west in afternoon during may.

Identification of current status of regions is being considered as first step in regional planning development. This identification entails the analysis of different economic, social and cultural sectors. Devoting credit and resources among different regions demand determination of regional development level as well. Recently, policy makers consider planning techniques with particular emphasis upon environmental potentials. That is, these methods frequently take into account environmental, economic, social, and political grounds.These regional development imbalance have been led to uneven population movement namely migration from less developed regions to developing or more developed regions. This article tries to evaluate Iranian provinces development levels regarding migration issue using planning models and techniques. Different variables related to cultural, tourism, housing and construction, labor force and employment, medical and sanitation, communication issues were used and classified in order to evaluate the provincial development levels. It is inferred that there exists a meaningful correlation between development level and migration. This study dictates a better idea of provincial planning for policy makers.

Shahkoh range is located in northwestern part of Kermanshah province. It possesses ample water resources as well as fertile soil and climatic variations.The major objective of this article is to investigate the morphogenetic characteristics of the drainage system and more specifically to propose its quantitative relationships with lithographic and geomorphic specification of the region. Since, drainage locational patterns are being shaped by lithographic and topographic characteristics, faults, and climatic peculiarities. Drainage systems are inherently divided into some qualitative sub-divisions among which parallel, radial, divergent and convergent types received considerable attention.This study deals with quantitative investigation of this drainage system within its corresponding sub-basins and more specifically to determine the impact of litho logy and climate upon its development.From methodological stand point, geographical information system which supports digitalization of corresponding maps along with spss technique, and compilation of the relevant information banks containing length and rank of each branch proved to be useful. This is followed by calculation of length and conjunction angles of each branch within sub-basins. Statistical methods were used in order to determine degree of similarity between sub-basins taking into account their conjunction angles. It is argued that wherever two basins are close enough, there develop a cluster relationship in which their center acts as a gravity point. The degree of their combinations known under the concept of even succession and could be shown through fully branched diagrams.According to the relevant computations, basins numbers 8, 9 and 12 considered to be unique. It is argued that groups 9 and 8 with regard to possession of high drainage index and group 12 due to possession of relatively poor hydrographical net works are noticeable. The distribution of the drainage density index regarding the other basins is such that accommodate all of the other 17 basins in one big group. Drainages other than their classification capability are also being divided according to their conjunctions' angles. Sub-basins 1, 3, 4, 5, 6 are closely spaced. These clusters were carved out in limestone. Their lengths and elongations are among some of their specifications, which need considerable attention. Their prevailing processes include, mechanical weathering, snow avalanches, debris avalanches, and dissolution. Consequently, as such sub-basins 20, 16 and 17 fell into one group. This is explained by its very fragile litho logical composition as well as its limestone arrangement layers which is subjected to high degree of erosion. This situation is intensified by long annual duration of frost. Steep slop arrangement along with probability of alignment of south-east-north west fault may enhance conjunction angle of sub-basin 20. This study proved the existence of fault, even though; the geological map did not report it. Drainage networks in some places imposed on the litho logy. However, in some other regions, this situation paved the way for drainage expansion and development. It is concluded that in some sub-basins snow avalanches were determinant upon drainage development system. However, dissolution of carbonate stones and the existence of karstic-formation well supported poor drainage. Last but not least, steep slopes of basins 20, 17 and 18 have been led to great amount of debris accumulation.

The quality of environmental phenomena in terms of possession of dry, moist, cold and warm periods is being controlled by recurrent of synoptic system and air masses. This study aims to analyse the relationship between air-masses and wet and dry periods. Spatial synoptic classifition (SSC) technique was used to identify air-masses with regard to monitoring dry and wet periods. This method classifies the air-masses into six groups on the bases of their origin and path modification. These include dry-polar air-masses (DP), moist-polar (MP), dry-tropical (DT), dry moderate (DM), moist-moderate (MM), and finally moist-tropical.Typical-days (seed days) are required to determine the air-masses properties. The flow arrangement pertaining to low-level maps and 850 hectopascal illustrates the transition of specific air-masses to the study area.Initial criteria for determination of typical days (seed-days) in every station were done through precise and exact evaluation of the relevant data and level climatic maps and 850 hectopascal ones. This is followed by the evaluation of the air-masses pathes as well as their properties from origin to the study area. These seed days represent air-masses specifications of a particular air-mass. In order to cluster air-masses, variables such as temperature, dew point temperature, (FF), pressure (FF), cloudiness, wind direction and velocity pertaing to 3, 9, 15, 21 o'clock and 10 synoptic stations during 1961-99 were reckoned. Principle component analysis was determined as a useful technique taking into consideration the number of used dependent variables.Decimal, clustering technique was used to group air-masses. This in turn, led to determination of effective air-masses upon Iran south-west basins during winter. This is followed by proposing average climatic properties as well as reckoning percentage of frequency of each monthly air-mass of all of the stations for the above time-period.Consequently relevant maps were produced. Comparison between dry and wet periods indicates high and significant relationships with air-masses. It may be inferred that climatic conditions and climatic periods of the regions could be determined through recurrence of air-masses and their cumulative effects.

This article predominately aimed to investigate causes and backgrounds regarding the development of Ghetto in African cities. It stressed on desperate rural migrants who wanted to leave rural poverty and appeal to cities higher standard of living found in major African cities. Research method is based on documentary technique. This Study tried to identify the expansion of ghetto within cities as well as in cities fringes of Cairo (Egypt), Abidan (Nigeria) and Durban (South Africa). Poor migrants were forced to house in low quality, dilapidated slums. This phenomena is well associated with deficient governmental capability, political instability, lack of long - run comprehensive planning, vague urban law system, ethnical and racial clashes, central government dependency, prevailing looting and violence, deteriorated infrastructure all resulted from inconsistency between migration rate and urban infrastructure. Lack of coordination and convergence between different political levels (local and regional), consecutive administrative designation, inappropriate urban planning, insufficient constructive investment imposed negative impact upon urban politics. Taking into consideration Africa's internal problems, these poor areas are incrementally being expanded and create more and more problems.