فصلنامه فضای جغرافیایی
پیاپی 67 (پاییز 1398)

Flooding is a natural hazard. This phenomenon carries significant importance for Iran which is one of the world's six countries in terms of accident. Synoptic conditions of atmospheric circulation patterns are very important in identifying the risk factors that lead to flooding in heavy rainfall. This study used Morghak hydrometric station's daily and hourly discharge statistics as well as  daily precipitation data from the rain gauge stations and surrounding area during the period of 1360- 1388. Flooding date in the basin was extracted in order to study the flood-causing system in BAZOFT basin. Then, days of widespread rainfall in the questioned territory which synchronized with the occurred flood date were determined. Afterwards, four main patterns were specified through a cluster analysis on Euclidean distance of flood data in 487 sea level pressure. Thus, these four patterns were analyzed in terms of sea level pressure, geopotential height at 500 and 700 hPa, wind components, moisture flux convergence, and Omega. The results of synoptic maps analysis showed that when floodwater occurs, low pressure tab of the Mediterranean and Sudan spread toward the south-west of Iran and BAZOFT basin. The Mediterranean, Black and Red seas have played a role in strengthening the aforementioned tabs. Positioning of western wind through axes with cut off low pressure in this basin is the main factor of severe inconsistency and heavy rainfall. The results of the analysis of the convergence of moisture flux showed that torrential rainfall was mainly a result of water flow from the Sea of Oman, the Persian Gulf, the Mediterranean and the northern half of the Red Sea to the BAZOFT basin and moisture accumulation in the basin.

In irrigation science, accurate estimation of the water requirement of crops and horticultural products is one of the most basic pillars of design and engineering calculus (Islami and Qahreman, 2013).Observations on evaporation through the pans have not always been accompanied by precision. Also, the dense network of evapometry stations is not available and, on the other hand, the use of direct methods involves a lot of time and cost. Therefore, developing an alternative approach for estimating evaporation rates based on meteorological variables with the ability to measure and estimate more easily is necessary. In order to estimate reference evapotranspiration, using mathematical models with measurements of meteorological parameters as independent variables will be inevitable (Islami and Qahreman, 2013).Mohammad-Reza-Pour et al. (2015) presented modeling of monthly potential evapotranspiration using genetic programming in Sistan and Baluchestan Province. For this purpose, the reference evapotranspiration on a monthly scale using the Penman-Monteith method and based on meteorological data such as mean temperature, relative humidity, sunshine hours, wind speed and precipitation amount over a 40-year period at Zabol, Iranshahr, Chabahar and Zahedan stations was calculated and arranged in 16 separate time delay patterns. Then, modeling of monthly evapotranspiration values based on genetic programming using the GeneXproTools software was used to develop and implement genetic programming based models. The purpose of this study was to provide a simple, yet practical and accurate model for calculating potential evapotranspiration in order to calculate the evaporation rate from the surface using effective climatic elements in evaporation.

Kermanshah Province accounts for 1.5% of the total area of the country. This province is limited from north to Kurdistan Province, south to Ilam and Lorestan Provinces and east to Hamedan Province. In this study, due to the importance of growing season and water requirement for the growth and development of crops and pasture products, in order to estimate potential evapotranspiration at selected stations in the region, the sum of months of the year during the statistical period of 1995-2012 was considered. In this study, the GEP model was used to determine drought and evapotranspiration indices. The stations in the region were statistically surveyed and 5 stations in Kermanshah Province were selected. Then quantitative and qualitative data were analyzed by the run test in both Excel and SPSS. Then, the GEP model and software were used to determine the dry and semi-arid seasons and the seasons that were suitable for growing and cultivating. The accuracy of the estimated data was evaluated and finally, the zoning map of potential evapotranspiration of the province was prepared.

Important factors affecting the saturation deficit are temperature, wind, and relative humidity. Increasing the temperature and wind speed give rise to increasing the amount of the saturation deficit, thereby increasing the evaporation, and increasing the relative humidity, in contrast, decreases the saturation deficit, thereby decreasing the evaporation. Therefore, in this study, four factors of temperature, wind speed, relative humidity and saturation deficit as independent variables and the input of the model were used to estimate potential evaporation using the GEP model, and evaporation from the pan was also considered as a dependent variable in order to fit and evaluate the performance of the model. In examining the calculated values, it was observed that evaporation values estimated by the GEP model were close to the evaporation values measured through the evaporation pan and showed a very high correlation (r=0.98), which indicates the great efficiency of the GEP model to estimate the potential evapotranspiration in Kermanshah Province. In the present study, the IWD method was used for geostatistical interpolation, so that after calculating the potential evapotranspiration rate using the GEP model and generalizing the obtained values to the surface using the ArcGis software, the zoning map of evapotranspiration of Kermanshah Province based on the estimated and observed values was drawn. The survey of the zoning maps showed that there was very little difference between the results of the GEP model and the recorded rate of the evaporation pan and in the both cases, the highest evaporation was related to the western and southwest counties to near the center, and the least was related to the east and northeastern counties of the province.

In this study, the GEP model based on genetic algorithm was used to estimate the potential evapotranspiration. The results showed that there was a high correlation between the data obtained from the model and the evaporation pan. An absence of sufficient facilities such as the pan to record the potential evaporation rate and the incompleteness of existing statistics in most parts of the country reveal the importance of various methods and models in estimating the potential evapotranspiration based on the factors affecting it with a high coefficient of certainty. In this study, it was shown that the GEP model is an efficient model for estimating potential evapotranspiration in Kermanshah Province, and it can be used with high confidence to rebuild incomplete statistics and modify outlier data in the province. The analysis of the zoning maps of the potential evapotranspiration rate based on the measure of the evaporation pan and the GEP model showed that by moving from east to west and north to south, the evaporation rate was increased. The very important result obtained from the comparison of the annual rainfall of the province with evaporation was that from the beginning to the middle of the growing season, the plants of the eastern counties had a monthly precipitation more than evaporation, and this amount is reduced to the west, so that a little after the central areas (Islamabad), the amount of precipitation and evaporation is equal and then it decreases, and as we approach the end of the growing season, the situation is generalized to the whole of the province, that is more evaporation than rainfall, which indicates water scarcity and high water requirement of the plant, especially in the west to the provincial capital at the end of the growing season.

The present resarch was performed to investigate the changes of Ilam oak forests following the occurance of tree declines and Identifying and zoning of Dieback oak stands. To study the status of Ilam forests, before the tree decline, the satellite images of Landsat 7 ETM 2001 was used. In order to identify the declined oak forest stands, classification of declined areas in terms of  topography, size and location of damaged forests in the province by training sample method in geographic information systems, satellite images of Landsat 8 in 2013 were used. The results from comparison of the satellite images of 2001 and 2013 show that the area of Ilam forests decreased about 26073 hectares (from 542252 to 516179 ha) which about 12847 ha is belongs to decline stands and about 13226 ha is belongs to construction of towns, roads, and etc. The most amount and percentage of tree decline was found in moderate class of forest density, climates of cold semi-arid, cold Mediterranean and sub-humid ultracold, in elevations of 800 to 1200 m, low slopes 0-15% and south west aspects. Also the most amount and percentage of tree decline was found in the cities of Ilam, darrehshahr and Badreh.

Forests located in the Zagros Mountains, as part of natural resources have different services. Soil retention is one of the most important services of forests. Population growth in recent decades has led to intensifying the exploitation of forests and uncontrolled destruction of them. Knowledge of ecosystem services as a new approach can help to prevent the destruction of forests. Current study was done by purpose of considering the role of forest ecosystems in soil retention as an ecosystem service and identification of areas with high supply of this service. InVEST software was used to model soil retention (SR), as the capacity of ecosystems to retain soil, by their equations. The results of the study showed that because of increasing the LS and R factors toward the south part of Lorestan province, the maximum potential of soil erosion was seen in the this region (1000 t/ha). The role of forests in soil retention was highlighted because spatial overlay of forest cover with maximum soil erosion areas was seen in the south part of Lorestan province. According to results the maximum of soil retention was allocated to forest cover compared to other land uses.

Emissions of greenhouse gases and their continuous accumulation in the atmosphere directly affect the temperature of the air and increasing air temperatures is a serious threat to the climate of the planet. The purpose of this study is to determine the spatial modeling of seasonal temperature in Iran two data sets were used for this purpose 1- Average temperature data of 115 synoptic stations (1980-2014) and 2- EH5OM database data for the period 2015-2050 in the form of 3-hour observations (8 times a day) under the scenario A1B. The REGCM4 model was used downscale the EH5OM base data. Then the hourly temperature data of the air temperature is downscaled and with a spatial resolution of 0.27 × 0.27 arc, they were transformed into a 15-by-15-square-meter curry grunge method which resulted in a matrix with a dimension of 7200 × 4. The accuracy of the modeling data was evaluated using three (R2), (MAE) and (RMSE) statistics and their authenticity was confirmed with high confidence. Temperature modeling has shown that temperatures in Iran during the summer and winter seasons for the period 2015-2050 will increase under the A1B scenario with values of 0.91 and 0.33 degrees Celsius, respectively. Temperature Auto-correlation with Geary C statistics indicates the strong association of temperature spatial units in Iran. The center of gravity of Iran under the influence of global warming has been increasing in all seasons and also, the directional distribution function of the spatial deviation of the seasonal temperature of Iran was normal which has led to the discovery of the role of heights and the direction of a large rectilinear system of atmospheric pressure on the other at Iran's temperature.

Geotechnical studies with a minimum of experiments can prevent from many of the problems caused by drilling such as the cost and blasting enormous in gas pipes. The spatial interpolation methods were developed for these problems with different applications. In most research on interpolation, the data used that the coefficient of variation are low, so in this study we have tried capability mapping interpolation methods for data with the coefficient of variation is relatively high, such as resistance allowed the soil near the fault tested and the impact of clustering method to improve the zoning evaluated. Eram town in Tabriz city selected as a case study because of its proximity to the main fault with nonisotropic data's. For this purpose, in this study, various methods such as kriging, inverse distance weighted, radial basis functions, local polynomial for zoning and cluster analysis with Euclidean distance with minimum variance technique is used. The data used for soil authorized strength of 40 boreholes in the town of Tabriz city. Zoning for the first state is without clustering and second state is with clustering that the whole area is divided into three zones. The result shows clustering approach could improve results and estimates at least 2 percent of estimate and at least 5 percent of root mean square error. The interpolation methods, local polynomial function method is better than other methods.

Playas from the past century have been of interest to geographers and geologists. The role of playas as a valuable evidence of climate change has been the main focus of this study. The aim of this study was to identify the geomorphologic evidence of quaternary climate change in Meyghan play. For this purpose, the necessary information layers were prepared, or from satellite images P6 IRS (with spatial resolution of 24 meters) were extracted and the geomorphology map of Meyghan basin was drawn based on them. Then the Meyghan playground was reconstructed in humid quaternary periods with the assistance of four glacial, climatic, human and laboratory indicators.The Meyghan sedimentary basin is 5528 square kilometers. Meyghan playa has 135 square kilometers area and is located at an average height of 1675 meters above sea level and at altitudes of Alborz and Zagros, 15 kilometers north and northeast of Arak city.

In order to do this study, four glacial, climatic, and human and laboratory indicators were used as evidence assessment of wetter periods in Meyghan play. Then each of the indicators was identified and analyzed separately in Meyghan playa.Glacial Indices: For analysis of glacier indicators, digital elevation model, topographic map 1: 25000, satellite imagery IRS P6 and regional temperature map were collected. Then, by examining the shape of the curves of degree and conformance and their relationship with zero-degree line and satellite images, the circus placement was extracted from topographic map.Climate indexes: Regression relationship was established for calculating climatic indices, average temperature parameters and annual precipitation of 8 climatic stations in a 25-year long period. From 1987 to 2012, the regression relationship was established and its equations applied on the digital elevation model of the area.Human Indicators: A review of human indicators through observation of the field and exploration of the studied area, or strategies such as testing on the evidence available in the playa environment to prove human life in playas in the distant period, is a strategic one.Laboratory Indices: For laboratory studies, data from 11 trenches we collected from the study area was used. In the first stage, field and survey operations were sampled in the study area. In each of the trench points, a trench was drilled to a depth of 75 cm with a small chisel and a shovel, which resulted in the removal of 11 samples of sediment from different locations with proper dispersion. Samples were taken in plastic and carefully labeled. Photos were then taken from the sedimentary environment of the samples. The laboratory parameters in this study included Granulometeric analyze, orthoscopic interpretation, and XRD and XRF tests.

According to the Granulometry results of samples, calculating the chromobin index showed that samples 5, 6 and 7 were of river sediments and other samples were low sediment deposits. Most of the specimens also tended to fine-grained particles. According to the analyzes, the present sediments of the present day are greater than the second and third Shale, containing chlorite and Elite minerals, as well as volcanic rocks (belonging to the Pliocene period) of the basin, and, of course, with moderate sedimentary maturity. The average temperature of the area during the quaternary period varied from a maximum of 2.67 to a minimum of -6.6 ° C. The results of morphoscopic analysis showed that in the transport of sediments to beech groves, in addition to the wind process, the blue process also played a significant role. Cumulative curves drawn on the basis of granulometric studies were also characterized by broken straight lines indicating that various mechanisms caused the sedimentation in the studied area. The analysis of the oxides of the main and secondary elements of the area showed; the origin of the deposits of the sediments of the area were of igneous rocks. From other points in the morphoscopy of sediments, it is found that kaolinite is found in the area of the plain, which goes underwater, and is much less visible on the margin of the playa, which proves the formation of kaolinite in the playground in Playa. Slowly Angularity of almost all quartz particles is evident in all samples, indicating the physical destruction of quartz during transportation to the desert and, of course, should not ignore the relative resistance of more quartz minerals.

Reducing the groundwater level due to irregular exploitation of these resources has caused land subsidence in most plains of our country. Study of this reduction in the groundwater level and trend of changes is essential for groundwater resources management and prevent adverse effects of irregular exploitation. In this paper, the indices of groundwater resource index (GRI) and the water level standardized (SWI) as two important index in hydrological drought were studied. To this goal, data from 40 pizometric wells located in Sari – Neka plain was used during the period of 30 years. In this study, first indicators of GRI and SWI in a year using the existing relations in the software Minitab 17 and M.S. Excel 2016 were calculated. And then, Using Mann - Kendall and Sen's slops in the application environment Makesens trends were examined. The results showed that both indices at the level of 99% has been declining and drought severity based on these two indicators has increased with time. As the drought severity in two indices for annual scale in 1394 and best wet for two indices for 1369, The main reason for the increase is the number of wells in operation, resulting in irregular exploitation of groundwater resources for agriculture in plain.

Climate can easily be considered as the most important factor affecting human life and the life of human societies. Perhaps the importance of the climate in human life has never been stressed as much as it is today in macroeconomic-social debates. Nonetheless, even today, many decision-makers of macroeconomic issues are not that cognizant of the importance of this issue. Now, most experts of political, economic, social and environmental issues present climate change as one of the most complex and influential issues in various areas of human life. They also predict that this issue will bring about different problems and consequences for human societies, depending on their economic, social and environmental context, especially in economic terms. Although the issue of climatic fluctuations and their economic impact on human life is not a new issue, the issue has recently taken a different turn. The financial costs incurred by climatic fluctuations will be very heavy and even irreparable for some areas and countries. In total, climate change is expected to impose, either directly or indirectly, significant economic impacts on human societies in various fields – especially agriculture, tourism, energy, human health, labor productivity, employment, economic growth, rising poverty, and increasing immigration, among others. However, the economic impact of climate change will not be equal and alike the world over. In other words, for some regions, climate change can be considered as a geo-economic opportunity and economic advantage, especially in the world economy and economic relations; in contrast, climate change for many regions and developing countries with very hot and dry weather is a geographical and economic crisis and bankruptcy. Due to the importance of the subject, this article tries to study the economic effects of climate change through a descriptive-analytical method. The issue is studied due to the fact that the literature of climate change in the Persian language is scarce; as well, from the climatic and economic point of view, Iran is one of the most vulnerable areas for climate change.

In recent years , there is more attention to migration from developed areas to un developed areas, so it highlighted the return migration. It can be said , it is a circumstance that individual or individuals selected their own country for residence from where  based on different reasons migrate to their own country or first areas. Aim of this study is recognition motivations of return migration and rates of economic and social changes and development of rural areas. The methodology of this study is based on functional aim and description –analysis nature and its framework based on survey. The requested data gathered from 260 returns migrates of rural of   Ahar at year 96 with using multi-stage cluster sampling method and for investigating gathering data is used document and library and questionaries’ technic. Spss and Anova, correlation test, regression and mean deviation are used for analysis of data. The obtained results of multi and two variables regression are shown that economic motivation of return migrant is most effective variable in rate of changes and developed of rural. Also, having land at rural effects on motivation of return migration, social cooperation and changes and developed of rural area. Using mechanizes and technology methods of agriculture effect on motivation s of migrants and social cooperation and developing rural. With regard to obtained results of multi – regression, economic motivation (36%) has more rate of economic-social development, and at total (52%) rate of rural development is determined by economic motivation of migrants, social cooperation, social motivation of migrants and using modern technology of agriculture.

Quality of life is one of the factors that today has a special place in urban studies. Efforts to improve the quality of life and its satisfaction in dysfunctional urban areas, especially in metropolises, due to a problem called burnout, and this problem has caused vulnerability and severe dissatisfaction with the quality of life in these tissues, has now become one Urgency and necessity have become. Therefore, in this paper, the purpose of identifying and measuring the effect of factors affecting the quality of life in inefficient tissues in the 12th district of Tehran is to enhance and improve the quality of life environment in these tissues. Based on this, the basis of assessing the quality of life in the inefficient tissue of the 12th district of Tehran is a measure of satisfaction with the quality of life in these tissues from residents' point of view. Statistical methods such as T-test, multivariate regression and Path analysis have been used to measure the effect of factors affecting quality of life. The method of this research is "applied" from the point of view of the "descriptive-analytical" study method and the collection of data and data is in both documentary-survey and deductive-deductible. The sample size of the study was 384 with regard to the inefficient tissue population of the 12th district of Tehran and using the Cochran formula. The validity of the questionnaire components was verified by a number of experts and faculty members of the university. Also, to verify the reliability of the research tool Also, the pre-test method and Cronbach's alpha coefficient were used. This coefficient was calculated for total indices of questionnaire 0.791 which indicates the appropriate and acceptable reliability of the questionnaire's tool and its structural validity is examined by factor analysis. The results of the research show that the satisfaction of the components of housing, physical-physical, social, economic, transport, environment and services is significant and indicates a low level of quality in these indices. Housing, physical, environmental and economic factors have the most effect on satisfaction with poor quality of life in 12th district of Tehran.

The use of methods that can meet the diverse challenges of traditional cities is inevitable. In this regard, the purpose of researching, localizing and prioritizing the criteria of New-urbanism as a holistic approach to urbanization in traditional cities is the case of Ardabil. The research method was descriptive-analytical and the statistical population consisted of urban experts and citizens of Ardebil who met the inclusion criteria. In order to identify the criteria of New-urbanism in accordance with traditional cities, two methods of library and Delphi technique based on expert opinion were used and localization in traditional Ardebil city, using two Delphi techniques with expert opinion and questionnaire with local residents' opinion. Questionnaire and AHP technique were used to prioritize native criteria. The findings of this study resulted in the identification of 17 criteria of new-urbanism in the traditional city of Ardebil in five dimensions: 1- physical, environmental and economic (five criteria) 2- traffic and transportation (three criteria) 3- housing and urban context (Three criteria) 4- Management and participatory system (three criteria) 5- Social, historical and traditional (three criteria). The research findings in the field section showed that traffic and transportation dimensions with weight 0.194 ranked first, housing dimension, urban texture 0.223, second, physical, environmental and economic respectively 0. 160. Third place, management dimension and participatory system with weight of 0.097 ranked fourth and finally social, historical and traditional dimension of weight 0.063 ranked fifth and out of 17 indigenous criteria, pedestrian with weight of 0.223 ranked. First, high density in textures weighing 0.144 second, sustainability in neighborhood structure, and emphasis on public transport and diversification weighing 0.88 in the third rank and planning criteria. And strain weighing0.013, social interactions, weighing0.012and benchmark the context of historical value with a weight of 0.006respectively in the ranking of the Hereafter low priority.