Journal of Geography and Planning
Year:2010 | Volume:14 | Issue:30|Papers Count:9

This article is an attempt to evaluate the changes in urban hierarchy in west Azerbaijan in the period of (1956 - 2006). In this Province during the mentioned period Urmia had always been on the top of the pyramid of regional urban hierarchy as in 1335 the size of this city was the same size of the second city (Khoy). In 1385 the size of Urmia (the first city) was 3.3 times Khoy (second city) and also 592 times the size of the last city (Simineh). We evaluated urban hierarchy in West Azerbaijan Province using some models of urban and regional planning. This work benefits from documentation and Excel software for data analysis. In conclusion urban hierarchy in West Azerbaijan urban network is unbalanced while small and medium size cities should be supported to establish desiredurban hierarchy and also to fill in the residential vacancy.

Alvand Mountain is located in the direction of north-west and south east of Hamadan Province in the west of Iran. The morphology of its north front causes instability due to the tectonics and different factors of erosion. Using determination of the rate of erosion or studying elements affecting geomorphic structure, one can assess the rate of slope instability. For assessing cliff morphology retrograde transformation of northern mountain front of Alvand mass, the region has been divided into 12 sub-watersheds, and using different indexes such as decline, retreat, replacement, rounding, sinuous mountain front faceting river gradient indexes, thalweg on deep index, and fans area index transverse topographic symmetry factors, the analysis was carried out.Results define the intensity of morphodynamic activities and erosion in sub-watershed the region and Alvand Northen slope instability. The existence of such slopes not only cause transformation but they also result in decline, retreat, replacement and rounding processes. The retrograde and transformation of mountain front in Alvand, are triangualar and the exit of shutter ridge, facets and sinuous forms of Alvand are sometimes linear and at times curvelinear.This fact expresses retrograde and transformation that was affected by drainage basin spacing, time and wide area. It seems that north mountain front of Alvand mass was under prelacier effective erosion system that causes retrogressive transformation.

Public spaces have a great capacity for developing social human aspects due to social interactions and participating in social life of cities. Responsibility of these spaces not only can develop social and individual human aspects but it also can improve person to person and person to place interactions. In this article, the aim was to achieve principles and indicators of designing responsible public spaces by applying archival study technique. Reviewing literature shows that there are different indicators that refer to different physical and activity aspects of public spaces. However, regarding those indicators from one hand and different aspect of place (Canter’s model) and human needs (Maslow’s model) on the other hand, a “responsible public space” can be defined by four main aspects. These aspects that have been discussed in this article include: Physical, activity, social and meaning responsibility each of which has its own special indicators.

Due to the increasing number of motor vehicles, street crossing has become a big pledge. However, sometimes pedestrians face with accidents and undergo physical injuries, and money loss, and also spiritual damages. With regard to the importance of this subject, the present article has attempted to study quantitative and qualitative aspects of official pedestrian crossings including zebra crossing, school crossing pedestrians, Pelican crossing, pedestrian refuges or traffic islands, and finally, the pedestrian facilities of signal junctions in crossings. Apart from the unique characteristics of each of these crossings, it should be noted that provided that the pedestrians are planned and designed in an appropriate way, they will increase the crossers' immunity in addition to the creation of traffic order and regulation. In our country the pedestrians, are limited to Pelican crossings and in exceptional occasions such as large urban centers to signal junction facilities. Therefore, aside from the recommendations that can be made over and above the appropriate site selection, is the correction or optimum construction of many types of Pelican crossings, school crossing patrols, and the presentation of pedestrian facilities on the basis of principles and standards that are mentioned.

In this article we have studied temperature elements (dry temperature, wet temperature, minimum and maximum temperature) and their fluctuations forest and non-forest environments. In order to observe temperature in two climatic stations the study was carried out in three elevations of 170, 130 and 5 cm at three local time zones 07: 30, 12: 30 and 18: 30.Results showed that in forest environment the average dry temperature and maximum temperature was low as compared with non-forest environments and great differences occurred in 5 cm elevation in forest and 4.6C at 12.30 p.m. and 4.2C at 18: 30 p.m.Average minimum temperature in forest environment was higher than non-forest maximum differences which was in 170 cm elevation at 06: 30 a.m. as high as 0.3C. The authors did not observe any trend in wet temperature element.

Relative dated deposit layers of Quaternary alluvial fans and their sequences in two regions in northwest of Iran, provide timelines for the assessment of the synchrony of the response of alluvial fans to late Pleistocene and Holocene climatic changes. In these regions three alluvial fan systems have been mapped: Two alluvial fans by the names of Koshksarsy and Sheykh-chay on the northern slopes of Mishow-dagh mountain range and Parsian fan on the northern slopes of Keyamaki-dagh mount. The conformity of deposition sequences in study area suggests a synchrony in climatic change phases, and a similarity in the response of alluvial fans to these changes. In the cold and wetter periods, high water and sediment supply from the catchments hillslopes is followed by debris-flow activity in Mishowdagh alluvial fans that intensifies debris-flow in Parsian fan system. In the warm periods, depositional processes change from debris-flows to fluvial processes that provide the way for soil development on hillslopes and alluvial fan surfaces. In recent periods, other mechanisms such as calcium carbonate precipitation and tufa deposition were active on the Parsian fan surface.

Some cities in Iran face with the urban sprawl. It seems that city trips which are done in their periphery need more time and cost than the ones near the center. Private vehicles are used in majority of these trips. For proving this hypothesis with the descriptive-analytic and surveying method, urban sprawl in Yazd during the years 1362-85 in comparison with the past was explained by using the periodical map for having different indicators. Then a survey was done by providing some questionnaires. The results show that those in the periphery have longer and more expensive trips than those living in the center of the city. These trips include common and daily movements (such as those done by their private vehicle).

Having precise information about hydrometrics is essential so as to perform effects such as watershed management or activities related to urbanism, establishing transportation lanes and so on. Existing registered information gained by hydrometric and climatic stations has made it easy and typical to calculating the relationship between precipitation and runoff as well as estimating the maximum out put of runoff due to bottom lands and runoff, in most areas, but often this estimation in basins denuded of the hydrometric stations is problematic. The existence of cities and crossing the roads over the numerous flood channels in these areas has made necessary theestimation of the maximum output of runoff.This article studies flood waters of "Soghad basin", an arid basin which is lacking either hydrometric or climatic stations.The first step was to estimate the maximum precipitation in 24 hours using the adjacent ecological station and Thiessen polygon method and calculate the amount of runoff resulting from precipitation through experimental formulas. Final step was the comparison of dimensions of flood way in output point of the basin and the maximum debit of runoff resulting from a range of precipitations. The precipitations that might promote the discharge was then specified, those which might disturb normal condition of the flood channel, that is followed by floods.