GEOGRAPHICAL RESEARCH
Year:2009 | Volume:24 | Issue:1 (92)|Papers Count:9

In December 16 – 21, 2005 occurred a wild spire forest fire on about 150 hectares of Gilan and Mazandaran forests. In regarding to study of these less precedence fires, data of frequency, area and time of fires and also their synchronized meteorological data were obtained. The following results are based upon the analysis of the weather pattern of the fire period by using Franciele method and synoptic-dynamic analysis in the study period: during the fire relative in the lee slopes of Alborz relative humidity decrease to %20 and temperature increase to 25oc and in the windward slopes have occurred precipitation and also cloudy conditions. For this reason it seems föhn event has been main factor of fire. Also in the period the calculated Franciele coefficient (k ) shows high dangerous stage of fire ability (0.3 < k). In the case of weather conditions, in these times, the surface maps shown a high pressure tongue that indicated by1020mbisobar and along from a high pressure in west of china with a 1050mb closed sell in its centre. the tongue covered internal area of Iran and southern slopes of Alborz Mountains. In the upper maps it has seen that a ridge with north – south or northwest - southeast axe located upon west-half and north-western of Iran so its upstream portion located on south and west of Alborz Mountains and downstream portion located on north of Iran. Sort of pattern makes possible to move the westerlies from Alborz mountain created fohn wind. Both zonal and meridional wind components are positive that’s mean westerlies moved from southwest direction and created a suitable condition for föhn phenomena.

Marginal settlement phenomenon, as spatial disequilibrium for population distribution, has caused many difficulties in iran. in some societies, attractiveness of industrial, employments opportunities, welfar state and adminstratives are resons of marginal settelments, aginest societies that is Conseqvense of uneployments and poverty. This status is more critical in Iran and especially in Provinces located in dry regions. Extensive migrations have been done according to these Conditions.These migrations produce pseudo employment and irregulars and erratics conditions in destination cities. The main purpose of this article is to analyze outcome of migration in Birjand city using 500 household Results in dicated that migrations, poor econamy and mismanagement have been created marginal settlements irregular Society with poverty and indigence. There fore, households of this societies don’t have hygienic, recreational and safety equipments. The marginal statements has cused dispute condition in Birjand city and if this tend continues, can be dangerous Crisis in futuer.

The Mereg watershed is located in Kermanshah province with 1466.150 square kilometer area, in west of Iran. It is one of up streams of KRB (Karkheh River Basin). Over exploitation of grand water and miss management have been caused undesirable conditions, what are reason of depletion of ground Water level. the main purpose of study was identification of site-specific to artificial-recharge in Mereg watershed In the first step, longitudinal and latitudinal profils of ground water level for 9 year between 1969-2006. Based on ereated profils, the zones with depletion of level (critical zones) were identified. Then, fifteen layers containing slop, land use, geomorphology, thickness of alluvium, lithology, soil, water table, dropping transfer coefficient, runoff areas, hypsometry, drainage network, fault, qanat, isothermal surfaces and isohytal have been prepared. These layers were weighted according to the three mathematical models including Boolean, Multi-Class-Maps and AHP and based on tow common methods of including surface and injected were intergrated. artificial recharge aquifers. Ultimately, the final maps were classified in two classes including favorable and unfavorable for Boolean model and five classes for Multi-Class-Maps and AHP including high favorable, favorable, medium, unfavorable and high unfavorable. In order to assess models, the most suitable units in three methods consist of slop, geomorphology, and lithology maps have been considered as field control; units with highest score in each model compared with suitable units in three layers. Results showed AHP model with most overlap and less area was selected as the best model. The second rank was for Multi–Class-Maps and Boolean method was categorizd in last rank. The average overla in these models Basedon and two methods were 97.8, 97, 93.7, 95, 78.6, and 84.6 respectively.

The global economy is strongly depending on natural gas and this energy resource is one of the most important elements of what the world needs in the future. Therefore, controlling these energy resources and its routes has become one of the power means.Indeed, those countries which have these resources and produce gas can apply such economic means to achieve their own political objectives as well as to gain prestige in the international arena. To this, to create an organization by the exporting countries in order to clarify the goals and to present the logic and good method for maximizing their interests is very essential.Therefore, it would be very significant to explore the GECF’s objectives. It is also important to illuminate the geopolitical and geoeconomic changes which will be caused by such organization both in regional and global level and its impact on the exporting countries’ economy and politics and those countries which consume gas as well.

The city of Mashhad will carry a population of nearly three million people and its annual water requirement will be nearly 300 million cubic meters. Concerning the role of underground water resources in the supplying drinking water protection of wells inside the urban area is an inevitable subject. Therefore a comprehensive planning and management of water resources for the protection of drinking water wells against the danger of contamination is an urgent issue. One of the important factors in this kind of planning is the determination and the observation of hygienic surrounding of drinking water wells. The hygienic capture zone of a well is the area around it which should be far enough from the well to the extend that if there is a little contaminated piece within the area, it should be eradicated in its path toward the drinking water well in a period of 50 days and create no danger of contamination for the water of that area. Therefore, in order for the drinking water well to be without microbial pollution, there should be a proper distance between the polluting resource and that water well. Since a remarkable number of Mashhad drinking water wells are located inside the urban area, determination and improved and precise calculation of water well surroundings should be performed based on the scientific basis, because the assessment and the execution of smaller surroundings will increase the danger of water well contamination and a larger surrounding for the water well will entail the waste of asset. For the assessment of hygienic surrounding of 174 drinking water wells of Mashhad, the mathematical model of microorganism transfer which is one of the methods of numerical calculations of biological surrounding of a well has been used in this research. After determination of hydrodynamic coefficient of water table for each one of 174 mentioned water wells, the coordinate lines of reaching the contamination to the water wells has been determined and drown by the Kinzelbach model in the Visual Basic program, afterwards the obtained distances for each water well have been calculated and finally the hygienic surrounding of the drinking water wells of the city of Mashhad have been zoned by Surfer and Arcview software. The results of this survey indicate that drinking water wells of Mashhad because of the difference in the particulars of their water table have different hygienic surroundings in different areas of the city. The variation of which is between 270 to 350 meters. To the extend that in the central areas of the city (the areas of the Holy Shrine toward Shohada and RahAhan Sq.) the hygienic surrounding of the water wells is between 270 to 290 meters and moving toward the north western part of the city of Mashhad, this surrounding increases to 320 to 350 meters, therefore the hygienic surrounding decreases from west and north-west part of the city of Mashhad toward the Eastern part of it.

In order to explain historical geography of Mokerian during the last four centuries geographical conditions and area of Mokerian Kurdistan has been discussed based on approaches and references. According to the data and information, location and area of Mokerian was investigated and its location on present maps has been identified. In studies of physical geography, relief and topography properties has been considerd. In relation of human geography the characteristics of of human geography in the studied area was investigated. Analysis of the results was carried out using expansion of Mokerian territories under different conquerors resolts indicated significant changes on area and territories. These changes were in relation to the power and weakness of captors.

The proportion of daily precipitation to the annual precipitation (PDPAP) is a criterion to recognize the intensity of daily precipitation. The high proportion demonstrates that it is possible for the annual precipitation to occur only in a few days. The high proportion reveals that having heavy and showery precipitation is normal. In contrast, the low proportion shows that there are moderate precipitation and more precipitation days. In the present research, data of the highest amount of daily precipitation of 46 Iranian synoptic stations from 1976 to 2005 were collected from the country meteorology organization to measure the proportion of daily maximum precipitation to annual precipitation. In the first, statistical methods including correlation tests, simple and multiple regressions, analysis of variance and the Friedman, nonparametric tests were used to measure the impact of independent factors of height, geographical longitude and latitude on that proportion and to judge the significance of the proportion changes of daily maximum precipitation to annual precipitation during the statistical period as well. Then, charts and maps were used for visual assessing and finally by using the Ward, s clustering method, the continental survey of the stations under study was presented based on the proportion of precipitation. Measuring the impact of geographical latitude on the proportion of daily maximum precipitation to annual precipitation of Iran showed that the proportion is increasing with latitude declining. Evaluating changes of the proportion of daily maximum precipitation to annual precipitation during the statistical period in the stations showed that those changes were significant only in the case of the Sanandaj station. Those changes of the proportion throughout Iran (46 station) made it clear that the first decade did not have any significant relationship with the second one, but changes in the third decade had increased in a significant way in comparison with the first one. The results also manifested that there was a significant relationship between the maximum amount of daily precipitation of the stations and their annual precipitation. Eventually, the continental survey of the stations illustrated 5 continental classes based on the proportion of daily maximum precipitation to annual precipitation in Iran.