GEOGRAPHIC SPACE
Year:2013 | Volume:13 | Issue:43|Papers Count:13

Glacial activity has been existed in Zab Kouchak river Basin especially in western and northern highlands during glacial periods and digging of the glaciers are remained as circus and glacial valleys. Other glaciers works in the basin are being deposited glacial sediments on the slopes and river beds which cause mass movements. In the research was a determined domain of glacial deposit by using topographical maps of 1:50000, Radar data of Aster Sensor, LISS III and Panchromatic images of IRS Satellite and climatic data during 1365-1387. Weighted Sum analysis was carried out in order to determine zones of instability in Zab Kouchak Basin. Because of using different variables, we compared them and also coefficients were presented for each of the variables. The results showed that there is high instability in Zab Kouchak Basin. High and very high unstable domains are in conformity with slopes of cirques and valleys end up to cirques. Also the terraces on the edge of river valleys are unstable. Especially the terraces remained at altitude of 1600 meters in Silveh, Zivkeh and Mashkan villages near the upstream being formed of glacial deposits are the most unstable parts of the area. Fans and terraces of this river basin were exposed to drastic changes. The nature of the glacial deposits and their susceptibility to human economic activities has created hazardous conditions, so that Lands on the terraces are affected by landslides. Several falls have occurred in valleys of the edge roads during rainfall and materials and also sudden flood waters can threaten roads and bridges. Fish breeding centers and rural settlements along the river and on the loose glacial deposits are at risk of land instability.

Nowadays integrated multi-criteria decision making (MCDM) and geographic information system (GIS) are commonly used in order to solve spatial problems. Different multi-criteria decision making techniques present different methodologies with certain limitations and advantages. Regarding mentioned limitations it is not simple to choose one of them. In this article, combined FAHP technique is used in order to minimize the limitation. By using Fuzzy and AHP techniques we proposed a methodology for site selection problem. After importing green space criteria in GIS framework we used them as criteria in AHP tree. By utilizing improved analytical hierarchy process through Fuzzy set theory, we tried to calculate weight of each criterion. FAHP is AHP improved by fuzzy set theory which is a useful approach for evaluating complex multiple criteria alternatives involving subjective and uncertain judgments. By using fuzzy set theory in AHP method the qualitative judgment can be qualified to make comparison more intuitionists and reduce or eliminate assessment bias in pair wise comparison process.

Solar radiation reached to ground as one of the essential factors for studies of water resources, environment, agriculture and vegetables coverage, designing the systems for use of clean energy and other numerous cases, has a wide application. This factor is not measured in all meteorological stations and therefore has presented a lot of empirical methods by the use meteorological, astronomical and geographical parameters for estimation. The purpose of this study is estimating the total amount of radiation reached to horizontal surface using climate parameters (minimum, maximum and average temperature, minimum humidity, sky cloud inees, sunny hours) and it’s classification in East Azerbaijan province. Thus, the measured monthly data of solar radiation in Tabriz station during 2001 to 2006 were used for modeling. The climatic data of 6 synoptic stations in the province during 1987 to 2007 were used to estimate the amount of radiation. By calculating multiple regression coefficients the accuracy of the model was analyzed. Required layers in GIS environment were created and by applying regression model coefficients in created layers, the total amount of radiation on horizontal surfaces in the province was estimated. According to the distribution of monthly radiation maps at the province area, the radiation pattern in the province was divided to four periods: winter season, spring, summer and autumn. The lowest radiation amount is in January and the highest amount is in June. Distribution of annual radiation in state shows the reduction process from the south west to the north and northeast. Average annual radiation in the province, are 4244 W/m2/day. Amplitude changes of annual radiation in province are 443 W/m2/day and the spatial variability coefficient is 2 percent.

In this paper, the probability of drought and wet year occurrence in Tehran by applying the first-order Marcov chain on Standardized Precipitation Index (SPI) time series in the scales of 6, 9, 12, 24 and 48 month were investigated. For this purpose, we used the monthly precipitation data of the Mehrabad station from January 1950 to December 2006. After that, SPI were computed in mention scales. Then, the conformity of SPI time series to the first-order Marcov chain were tested statistically by test statistic X2 and also confirmed. In the first of all, transition probability of drought, wet year and normal state were computed. In addition to, middle number of drought and expected wet year for future were forecasted. The result showed that transition probability of every state to it is more than other states. The probability of Pdd (the probability of drought after drought) is more than Pww (the probability wet state after wet state). Whatever, the time scale of SPI become longer, its stability is increased. On the whole, the probability of normal state is the most among all and the drought equilibrium probability is more than wet year. Whatever time scale of SPI became longer, the number of drought is decreased and its duration is increased. In the of all, occurrence probability of drought is more than wet year.

Natural hazards in different areas each year will be causing great damage. Hail as one of the major climatic hazards, a lot of damage in different parts of the environment, especially agricultural and horticultural products are created. Understanding of tempo- spatial distribution this phenomenon, much to the prevention of damage caused by this phenomenon, it can help.In this study, data on days with hail, in the period 1987 to 2007 and number five synoptic stations in Kermanshah province have been used. Method used in this study, is the Piossio distribution probability. The results showed that the probability of this phenomenon in the growing season of horticultural crops is very high so that the highest percentage and probability of occurrence of this phenomenon, to be in April and then May. In these months, still in early stages of plants and trees in bloom and are very vulnerable. A surveillance zone also showed that the most vulnerable areas of the hail event are the western province (Sarpolzahab station) and in the eastern province of Kermanshah in Kangavar station.

The study of synoptic rainfall has been an important parameter in the study of torrential rainfall. Every year rain induces floods which cause a lot of financial and economic losses in Lorestan province. These flood producing rains are the result of some special synoptic situations. From the meteorological maps of NCEP, the synoptic analyses of 24 major floods were studied. The results of the study showed that on the ground and at the level of 500 hp, heavy rainfalls in Lorestan have originated four patterns. the first pattern: The movement of Siberian high pressure to west and its combination with Azure high pressure, cold advection form east north to Iran, cold advection from Europe to north Africa all cause the transmition of moisture into Iran and the production of Sudan system, warm advection from Persian Gulf by Arabian subtropical high pressure to Lorestan province. The second pattern: This pattern shows that Siberian high pressure is very strong moving to Iran and warm water in south Iran causes warm and humid advection to Iran and Sudan system and combination whit Sudan and Mediterranean system with Iceland system. The patterns include: Cold advection from high latitude by Island system and combination with low latitude systems, the fourth pattern, the combination of Azure high pressure with European air movement, the existence of a blocking system on the North of Europe which hinders the movement of the waves to the East and diverts the systems to lower latitudes, The existence of Arabian high altitude on the Oman Sea and Persian Gulf which causes the transmission of hot and humid weather into Iran.

The local periodic markets are interactive places for the tourists going to Guilan Province for shopping and recreation. Therefore, these investigation studies of tourism situation in the local periodic market its facilities to the tourists. Therefore principal question is “what role local periodic markets have in developing of local tourism”؟ Statistical society was calculated by Cochran’s formula which was included visitors.was included Numbers of visitors were 400. Sampling method was stratified and radom sampling. For data analysis we used SPSS software.Results show that the local periodic markets are interactive with a view to local dimension (local tradition, cloth, crops). Many tourists who travel to the region visit the local periodic market. Also, product quality, market discipline, management, interaction and time affect the tourists impetus. Finally, market discipline and product quality are important factors among all.

In order to carry out statistical and synoptic analysis of the sultry at the northern provinces of Iran, temperature, relative humidity, and saturated water vapor pressure obtained from Meteorological Organization of Iran in (1992-2007) period. The intensity sultry index and the partial water vapor pressure were calculated for each day. According to the defined threshold, the sultry days were divided into four groups. Statistical analysis proved that the August is the sultriest month with the average of 83% sultry. The Noshahr, with 149 sultry days, has the highest frequency of sultry days. Totally, west coast areas have more intensity of sultry than east coast areas.In order to synoptic analysis, 63 days of high sultry lasting two days or more, were selected The daily data of sea level pressure and 500 geopotential height were extracted from NCEP/NCAR database with spatial resolution of 2.5 x2.5 degree and then a hierarchical cluster analysis was applied using ward linkage method. Finally, the most important synoptic patterns were extracted which related to high sultry days. On the surface map was observed that Pakistan low pressure at the southern part of the country, and occasionally this low pressure penetrate into the study area. In addition it had been observed that high pressure tongue of Black sea and high pressure of north and west Europe in the area. Moreover on the base of synoptic patterns at the 500 hp level indicated that STHP was dominated.

Optimal and balanced distribution of allocated spaces to different types of land uses including, especially, health medical centers and hospitals, is one of organizational requirements. Accurate positioning of these centers is of organization requirements in terms of observing justice in access to health services for all segments of society. In this study, using GIS along with investigating the place-spatial distribution of abovementioned centers in Jahrom city, attempt was made to do a locational analysis and to make a prediction on the location of health-medical centers and hospitals (in the horizon of year 1400). Research methodology of this study was descriptive-analytical. Required data was collected by using 1/2000 landuse map, field observation and studying plans related to Jahrom city. And, using GIS and with the help of analytical hierarchy process (AHP), data processing and analysis has been made according to urban planning criteria. Finally, the most appropriate locations to create the desired centers were localized.

In planning recreational centers, considering the method of locating and spatial organization with regard to the geographic scale of the place plays an important role. The aim of this study is to determine suitable location for constructing residential centers in Tabriz using Analytic Hierarchy Process model in Expert Choice software and Geographic Information System. This study is a descriptive-analytical study and applies library and field data collection methods. Analytic Hierarchy Process (AHP) is a multi-criteria decision making technique used in locating. In locating process through this method, after determining hierarchy levels including objective, criteria, sub criteria and alternatives, pairwise comparisons were performed between categories for weighting. While weighting the categories, the analysis of compatibility of judgments was also performed. After weighing all criteria, sub criteria and alternatives, the final comparison of the alternatives with the objectives was performed and the results were presented in charts. The results show that, among the nine regions of Tabriz, region 1, having priority factor of 1.685, has the best conditions for establishing residential centers.

By developing urbanization and simultaneous of it, exploitation river resources from bed and banks of rivers speeded up increasingly. This expoit accompanied by changes in morphology and geometry of rivers. In this research we investigate geomorphological changes in parts of Kashkan River in Khoramabad county in Lorestan province from old Kashkan bridge to Cham Davood village along 14 km, which caused by removal of sand and gravels of the river bed. We used aerial photos of 1381 and satellite images of P5, Cartosat (for 2009) by an- eight -years’ time resolution to find and survey changes in river bends and bed width. By drawing two vector layers for river bed in two software environments of ARCGIS and AutoCAD, we calculated and get information on bed width in bendings of river, changes in Azimuth of river bends, the highest and the lowest radius of contact circles on rivers in two time intervals. During these investigations we detect changes during an- 8- year intervals in the river bed and compared changes. Field surveys and observations completed our research. Research shows that many bendings in river course caused by harvesting of gravel and sands during a short period of harvesting time, and regulations and rules of harvesting aren’t sufficient for protecting area from unexpected environmental changes.

The main objective of this paper is to investigate the long-run relationship between per capita income and environmental quality indices. For this purpose, we used the CO2 emissions and biological oxygen demand (BOD) per worker as a proxy for measurements of air and water quality. In this paper we used the Johansen's co-integrating technique for estimating the long run relationship between CO2 emission and water pollution with explanatory variables such as population density and growth rate of urban population. The results of this paper show that the EKC curve is confirmed for Iranian economy over the period of 1980 -2009. Moreover, the population density and urban population growth rate have positive and significant effect on the environmental degradation. The other results of this paper show that the elasticity of CO2 emission with respect to the population density is more than of water pollution and one percent increase in population density have led to 2.06 increases in CO2 emission.