نشریه جغرافیا و مخاطرات محیطی
پیاپی 1 (بهار 1391)

In the hydrology literatures flood is a flowing water with high discharge، which water level arise throughout the viver channel and flooding the land around them that usually not under water. During or after a heavy rain the river discharge increased sharply and the overflow of water from normal Channel and Flows in the floodplain and surrounding areas. If high pour، especially in showery conditions of inequality and vegetation، a large part of rain become runoff and interval shortly after the rainfall the current floods and the damage is usually. Flood zoning maps are widely used in studies flood plain management. Today، this maps is one basic data of studies and construction projects in the world prior to any investment or development projects، review by relevant organizations. Taleghan River watershed is one of the major subbasins of Sefidrood in the southern slopes of Alborz Mountains and is located in north western Tehran. This basin، is between latitude N36ْ 5 ''31 «to 36ْ 23 ''37» and the longitudes of 50ْ 21 ''00 «to 51ْ 01 ''16» East is lolated. In this study flood levels with interval occurrences of 5، 10، 25، 50، 100 and 200 years، in 6/5 km length of the Taleghan river Channel was determined by HEC-RAS model and HEC-geo-RAS rider. In other to، used of digital map 1:400 scale، and provide the TIN، then river and cross sections was determined. Finally this information were transferred to the HEC-RAS software، the geometric characteristics of the river and other required information was added. This information includes: Hydraulic data، Topographic data (longitude is and cross river profiles & river banks). Flood discharges one of the data needed for simulate، is the Manning roughness coefficient، in order to used of cowan respect. Also with the information of petite of sediment in the channels، the Manning coefficient of the field was determined. In addition to the items listed in this section، barriers in the path be entered، they include three bridges on the main route، group of obstacles is also the riverbank or is that residential fence or walls surrounding the houses fence or hedge and gardens have been constructed. The hydrological data، includes، discharge intervals، physical Charactrestics of River channel Related to paper purpose and cross Section is entered to the Software environment. Several factors are involved in a flood in a region that can be shaped increases or are prohibitively. Among these factors is lithology، vegetation، rainfall regime، basin shape، slope and construction of various structures in the path. In terms of lithology، the area studied there are formations related to Precambrian period، Paleozoic، Triassic، Jurassic، Cretaceous، Paleocene، Neogene، Pliocene and Quaternary. The range of choice، Type in riverbank sediments is generally quaternary alluvium that has a high susceptibility to erosion. Precipitation regime in this region based on Glynak weather station is about 500 mm and it is a Mediterranean regime. Month of March and May & April have the highest rainfall. Due to this، Taleghan river floods often occur in spring. There are 18 types of vegetation in the pasture، most land is included pastures. The shape of study area is roughly oblong that rectangular is much further risk of flooding is less in the intense rainfall. To study the basins used of the two methods، the elongation factor was used Gravlyus. In the studied area downstream، the Taleghan dam was constructed، resulting in sediment near the dam thus reducing the gradient to be this helps prevent the occurrence of floods. The results of calculation of water levels at different return periods، the HEC-RAS software through HEC-geo RAS rider was transferred to GIS and flood zones in each period were determined.. Differences in the flood zone، primarily topographic features is from the Valley. Obviously، anywhere the channel width is large، flood level increases. Unlike wherever the valley is narrowed As well as reduced of flood level and depth of flood level increases. The results show that the total area within 200 year flood is about 85/54% risk of flooding by floods 25 years and under. A large part of agricultural land and is part of the settlement this section is located.

Although temperatures in 0 and below 0 C° in the cold season of the year and mid latitudes are not necessarily considered an extreme phenomenon، but their long-term durability in a widespread area or their sudden occurrence in the beginning and end of the cold season can make this faetor an extreme extent phenomenon. The extreme phenomena are resulted from interaction between large scale atmospheric circulations and the local landscaps of the study area (terrain، altitude، etc.). Considering the geographical situation of Iran and relatively high altitude of most of its areas as well as entering different air masses to this land، Freezing occurrence involves most parts of the country each year، so in some years، even the southern parts of the country is affected، and makes a lot of damages. Thus، identifying the circulation patterns causing such an extreme phenomenon can be helpful in more accurate forecasting as well as management of the freezing hazard. Therefore، a goal to be sought by this study is to achieve circulation patterns identifying، which create pervasive frosts in Iran. Study area: Iran with an area over 1''648''195 square km is located between 25N to 40N latitudes and 44E to 64E longitudes. Iran''s landscape is dominated by rugged mountain ranges that separate various basins or plateaus from one another. The populous western part is the most mountainous، with ranges such as the Zagros and Alborz Mountains، the latter of which also contains Iran''s highest point، the Damavand at 5،671 m (18،606 ft). The eastern half consists mostly of uninhabited desert basins with the occasional salt lake. The only large plains are found along the coast of the Caspian Sea and at the northern end of the Persian Gulf، where Iran borders on the mouth of the Arvand River (Shatt al-Arab). Smaller، discontinuous plains are found along the remaining coast of the Persian Gulf، the Strait of Hormuz and the Sea of Oman. The climate of Iran is mostly arid or semiarid، though subtropical along the Caspian beaches. This study is focused on synoptic anomalies resulting in pervasive frosts in Iran with the aim of improving the predictive capabilities of this phenomenon in Iran. So، to achieve this aim، Iran''s frosts were classified based on a location principle into three categories، including pervasive frosts (occurring simultaneously in more than 65 percent of Iran''s area)، semi-pervasive frosts (occurring simultaneously in 25 to 65 percent of Iran''s area) and partial frosts (occurring simultaneously in less than 25 percent of Iran''s area). It should be noted that this analysis only covers the years with maximum and minimum frequencies the pervasive freezing days with pervasive frosts that were a standard deviation above and below the average (respectively، and) for a 43-year Records from 1962 to 2004. Them after، the frosts were assessed in three scales of annual، seasonally (from October to November، from December to February and from March to April) and monthly. The variables used to describe the extracted anomalies، include: Sea level pressure، upper and lower level geopotential height، surface temperature، humidity at the level of freezing 850 hPa، wind lines at 850 hPa and 250 hPa، associated with zonal and meridional wind at 250 hPa. As noted، the anomalies were extracted with respect to the study period (1962-2004) for all three sub-periods، including annual، seasonal and monthly periods. Data used in this section are the re-analyzed data obtained from the National Center Environmental Prediction (NCEP) with the spatial resolution of 2. 5 * 2. 5 degrees. Composites prepared for the maximum and minimum frequency of pervasive frost days show different synoptic anomalies for study variables so that the composites for the maximum and the minimum frequency of indicate negative temperature and humidity anomalies for the entire studied periods. Also، at low levels of atmosphere for the maximum frequency of the pervasive freezing contempory with days with pervasive frosts، a bipolar pressure anomaly with a positive value in the north east and a weak negative value in the north west of Iran above the Turkey. In other words، with a strengthened Siberian high-pressure system and extending its western flow on the Mediterranean sea، the conditions for establishment of a high- pressure system on this sea is provided that the result of such an establishment would be pushing back the low-pressure system flow of Sudan monsoon to the lower latitudes as well as provided synoptic conditions for moving the cold air from the higher latitudes to the western part of Iran. The wind field in the high levels also shows a one-polar anomaly of the stream function generally with positive sign (except for November) over Iran that such a one-polar anomaly causes an anticyclone circulation (with the exception of November) over Iran that such an anomaly shows the weakening of subtropical jet stream over Iran. It is also seen for the minimum frequency of days with pervasive frosts that the entire studied area is dominated by a negative anomaly، which its central focus of severity is located over the Turkey. Thus، the spatial patterns configuration of this group indicates the weakening of the Siberian high pressure or anticyclone and subsequent extension of its western stream to the Mediterranean sea that as a result، the conditions for establishment of a low pressure system or depression with a cyclonic circulation over the Mediterranean sea will be provided; this pattern is well coordinated with the wind anomaly at 850 hPa level، therefore، under these circumstances and with the expansion of Sudan monsoon low pressure stream and humidity injection from anticyclone circulation of the Indian Ocean (Arabian Sea)، Iran''s climate experiences a more humid and warmer conditions، which reduces the frequency of days with inclusive frosts over Iran. Based on a location criterion، the frosts in Iran were divided into three groups: Pervasive frosts، semi-pervasive frosts and partial frosts، and then، the anomalies of general circulation average of the atmosphere were investigated for years، seasons and months that had maximum and minimum frequencies of days with pervasive frosts. The atmosphere for the maximum frequency of the days with pervasive frosts، a bipolar pressure anomaly a positive value in the North East and a weak negative value in the North West of Iran over Turkey can be seen at low levels of atmosphere. Based on this anomaly، the configuration of spatial patterns of this group changes in a way that conditions for entering the anticyclones، both from the North East and the North West of Iran، will be provided. In other words، by strengthened Siberian high-pressure and its extended western stream over the Mediterranean Sea، conditions for establishment of a high pressure system over the sea is provided that results in pushing back the Sudan monsoon low pressure system to the lower latitudes as well as provided synoptic conditions for entering the cold air from the upper latitudes towards the western half of Iran. It is also observed for the minimum frequency of pervasive freezing days that the entire studied area (20 to 60 North degrees and 20 to 75 east degrees) is dominated by a negative anomaly that its central intensity focus is located over Turkey. Thus، the configuration of spatial patterns of this group indicates the weakening of the Siberian high-pressure and subsequent non-development of its Western flowing air up to the Mediterranean Sea; therefore، the conditions are provided for establishment of a low-pressure cyclonic circulation over the Mediterranean Sea that such a pattern is also well coordinated to the wind anomaly at 850 hPa level. Thus، under these conditions and with expansion of Sudan monsoon low pressure system and humidity injection from the Indian Ocean anti-cyclone (Arabian Sea)، under the abow Conditions، the Climate charechtrestics become warmer and wetter to cause the reduction of inclusive freezing days over the hole country.

The population growth and urban development are the effective factors of increasing the air temperature for urban areas، which may cause formation of heat island، which itself influences air quality and consequently، the public health. The heat island is one of the phenomena which effects the human beings’ living environment in urban areas on a large scale. The heat island occurs when an extra percentage of surface vegetation is wiped out and replaced with buildings، roads and other urban constructions. This problem causes the trammel of the ripe solar radiation into the urban structures during the day and its reflection at night. Thus، the natural process of earth surface getting cold during the night happens more slowly. Consequently، the air temperature of cities will be naturally higher than the temperature of suburb regions. Because of its important effects on environment and health، urban heat island was evaluated for Mashhad، as a major city in Iran، using satellite images and the fractal theory. Mashhad is located at latitude 36ْ 17 ''45 «-N and longitude 59ْ 36 ''43» –E. The population is 2410800، and it is one of the largest cities in Iran. An extra percentage of the surface natural covers is wiped out and replaced with urban constructions and many landscapes have changed into residential areas. Surface radiation emittance، as recorded by thermal infrared sensors، includes both topographically and non-topographically induced high frequency variations such as roads and edges which are caused by different spectral characteristics of different neighboring land covers. The use of fractals for analyzing thermal infrared images would improve our understanding of thermal behavior of different land-cover types as well as the effects of landscape pattern on thermal environmental processes. In this research، TM images of LANDSAT for June، 25th، 1992 and ETM+ of LANDSAT 7 for Aug، 6th، 2002 were used to study the urban heat island in Mashhad and also to obtain temperature and Land-use maps by using them. In addition، for better understanding of this phenomenon، the profiles in that direction of North-South، East-west and Northwest-Southeast were considered. Moreover، the fractal dimensions of these profiles were computed using the divider method، to as to have better understanding of thermal behavior of different coverings and the effects of land-space pattern on ambient temperature. The results showed that the surface radiant temperature of Mashhad during the decade 1992 to 2002 increased and this increase was remarkable in the residential areas. Land-use maps demonstrated developing of the residential areas for 2002 rather 1992، and many plant covers were destroyed and this subject was approved by calculation of the fractal dimensions. The relatively low values of fractal dimension suggested that the texture was less spatially complex. It means that the spectral responses to the thermal band along the line tend not to vary drastically. In urban areas due to the unsteady vegetation and roughness variability، the fractal dimension had high value. In northwest – southeast profile where urban or built-up cover had occupied the majority of the surface، the fractal dimension and temperature in both images were higher than other profiles. Because in east-west profile، urban area was developed more severely during 1992 to 2002، the fractal dimension increased more than other profiles. So، we concluded that، in Mashhad، the urban development resulted in increase of spatial variability، temperature and the fractal dimensions.

Soil salinity and expansion TTS it، in the arid and semi-arid areas is including environmental issues that in Recent years attention has been due to Population growth and the need to utilizeland. In order to human was tried that using of Different techniques determined salinity area Between remote sensing data in recent years have provided relatively accurate results as a source of information (Long & Nielsen; 1987، 221: Everitt et al; 1988، 1283: Csillage et al; 1993، 231: Verma et al; 1994، 1901: Bishop &McBratney; 2001، 149، Carre& Girard; 2002، 241، Douaoui; 2006، 217، Fernandez-Buces et al; 2006، 644: Melendez-Pastor et al; 2010، 55: Gutierrez & Johnson; 2010، 46،Bouaziz et al; 2011، 237). Also in Iran has been studied with remote sensing data and technique (Abdinam; 2004، 33، Dashtkian et al; 2008، 139، Nourozi et al; 2011، 59، Zare; 2011، 74). Remote sensing is as technique and science access to information about the phenomena without physical contact with the area. Also Geographic Information System is used as a system in collect، store and analyzes information related to the phenomenon. Obviously، that both techniques are appropriate for gathering information، making fast، accurate. In the two late decades using of field technique and mixture to remote sensing data has been significant aid to mapping of soil salinity. Remote sensing has capability and potential to extraction and problem study of salinity in Large-scale zones. Also remote sensing has provided forecast possible، assessment of salinity effect. Extractive salinity map has capability much in agriculture and other human activities. Darab Township is including regional that have Environmental conditions ofaridan dsemiarid، one of problems has been soil salinity. In this research we tried to using of landsat satellite image and also field survey extractive salinity zones and analyses Due to salinity. Study area: Darab township located in southeast Fars province and 54o، 11// to 54o، 24// east longitude and 28o، 33// to 28o، 49// northern latitude. Viewpoint of Geomorphology study area is part of Zagros south east (Fars region). In this region Zagros reached its maximum width and face rough appearance is different from other parts of the Zagros. So that waves of chains is more open and is panache as syncline ponds and anticline disks. Syncline ponds often has created very open plain (Darab plain) through arrival of anticline axis connected together. Most of the rainfall occurred in January. In the summer It has been very hot and dry Climates due to being away from moisture resource، water vapor entry path and sometimes the lack of qualified. This dryness status is also reflected in the rain. Of course is seen in Darab summer monsoon rainfall that is related to the southeast regime. This property is reflected in the days of 10 mm. In this paper the Materials relate to the topic was collected first using. After according to purpose research was used from satellite images Landsat (Landsat TM path and rows 161 and 40 to June 15، 2010 and 16 June 1987، with a pixel size for the thermal band 57 meter band panchromatic 25/14 meters and for the rest of the band 79 m). This image was downloaded of the GLCF site for easy access. After using of landsat image satellite (1987 and 2010 years) and Khaier method (2003) through detectiontechniques (Band 5 – Band 7 / Band 5 + Band 7) in software has extracted soil salinity zones. For superimpose of extraction map salinity zones to fact was doing field survey of study area. We Should say that the main technique in this research is detection pixels salinity represented. Also in this study using of geology and topography maps، digital elevation model (DEM) 30 m of Aster. To calculate the impact of climate factors was analyzed Darab synoptic station data. For ensure and accuracy finding was performed three stages of field survey. In the first stage was observed landforms of near. In the second phase was photographed of saline lands، their distance from salt domes and water way transport salt. In the third stage to validation findings was a complying extraction zone (with varying degrees of salinity) withthe earth surface، to have determined rate accuracy of calculation and soil salinity map. Finally was concluded based on research finding and investigate their right. Based on output map (image 2010)، 545. 37 square kilometers of the study area has high salinity (8. 33 percent)، 1804. 69 kilometers with significant salinity (27. 58 percent)، 2343. 41 square kilometers represent moderate salinities (35. 81%)، 1645. 23 square kilometers represent low salinity (25. 14%) and 204. 91square kilometers from the city Darab has very low salinity (3. 13 percent). Compare this map to extraction map (1987) has showed reduction highsalinity، significant،insignificant zones and increased lowand mediumsalinityzones. Result showed that salt domes are main factor salinitization of soil and between Corsia salt dome played most of role. In around of Corsia salt dome existences salinity springs that not observed in other salt domes. Every year the significant amount of salt through these springs has left besides the Corsia salt dome. Field observations show that almost half of the salt dome has been eliminated in the erosion caused by flowing water (rainfall showery). Their main symptoms are formation of salt fan in the foot of the salt dome. In late years Human with Creation trench cause to aggregation armed with salt water. It is interesting to note that field visits showed that salinization of lands caused by Corsia salt dome erosion has cut in the time to around، In other words has been limited salinization. It can be because Limit is appearance of Shahyjan River in east salt dome and Golabi spring in west its. Seem that extraction map of salinity zones can be significant role in environmental management for achieve tosustainable development. Major of land high salinity located in west and southeast of Darab. Can be that diversity of landforms has led Substantial area (60 percent) of the Land in Darab are capable to cultivate. Of course in north and northeast are seen Salt stains that due evaporate sediments. Exist of diver alluvial fans in north Darab and Fresh floods that every year transport and left Significant amounts of sediment (including soil، etc.)، its watershed from upstream to downstream and the city. So many of alluvial fans of Darab is active and been developed (but human interpretations of the sediments should be noted) and Prone lands have been prepared for cultivation. The main operating of salinity is salt dome in the study area. In Darab town existence six salt domes that among them Corsia salt dome plays most role in salinity of lands. Around this salt dome existences spring that each year remained a significant amount of salt in surrounding. Due to high salinity in around salt domes only plants can be growth that was resistant to salinity. In addition the effect of salt domes in the soil salinity، also groundwaters are affected by then. So that in Khosoei Strait the electrical conductivity of waters appears up to 5000  M per square centimeter. Existences of river and fresh flood have caused prevention to expansion of saline lands and its have washed the area well land and salt transport to Khosoei Strait. In the mouth of the Khosoei Strait Man has attempted to create a barrier that Behind the dam each year، some salt is left behind. In the past that that there was no barrier waters moved to the southeast through the narrow river TngeCharkhi. Salinity of Forg and Abshore area in southeast Darab was As a result، the river crossing. Of course join water of Fedami waterfall to river reduces extent of salinity in this section. So that Palm groves and lands in section Irrigation to river water. The achievement of this research is to determine to the salinity zones، identify and analyses effective factors on soil salinity in study area. Output map as a scientific document can play a significant role in environmental management.

A landslide or landslip is a geological phenomenon which includes a wide range of ground movement، such as rock falls، deep failure of slopes and shallow debris flows، which can occur in offshore، coastal and onshore environments. Although the action of gravity is the primary driving force for a landslide to occur، there are other contributing factors affecting the original slope stability. Typically، pre-conditional factors build up specific sub-surface conditions that make the area/slope prone to failure، whereas the actual landslide often requires a trigger before being released. Landslide is among the natural hazards that causes financial losses and destruction the natural resources. The combination of natural and human factors provides conditions for this unstable range event in the geomorphic transport processes. Landslide hazard is defined as the probability of a landslide at a specific location in space and time. Landslides result from a complex mixture of geologic، geomorphic، and hydrologic conditions causing damage and disruption to people، organizations، industries and the environment. Modification of natural conditions by human activities، such as road building and forest harvesting accelerates land sliding. Study area: Taleghan watershed with an area equivalent to 1326 km of SefidRoudis the major sub basin in the southern slopes of Alborz Mountain and the northwestern part of Tehran and is located 120 kilometers from the city. Annual rainfall Average and annual temperature of the watershed are 515. 16 mm and 10. 5 °C respectively. The outlet stream gauging station is named Galinak with an area of 800. 5 km2. A second stream gaugeis Joestan Station whichlies in the upper part of the watershed and has an area of 412. 7km2. The area is well-known for Iranian people for its mild، sunny summers and cold winters. A landslide susceptibility zonation (LSZ) map helps to understand the spatial distribution of slope failure probability in an area and hence it is useful for effective landslide hazard mitigation measures. Such maps can be generated using qualitative or quantitative approaches. The present study focused on the identity the Taleghan Watershed landslide effective factors and the risk ratio zonation of this event using logistic regression model in the Arc GIS software environment. Landslide zones layer as the dependent variable and geology، distance to fault، distance to road، elevation، slope، aspect، and drainage density layers as the independent variables were entered in the model. Logistic regression is an approach to prediction،like Ordinary Least Squares (OLS) regression. Logistic regression is typically used when the predictor variables are not normally distributed and some may be categorical. The spatial prediction is modeled by a dependent variable and a number of independent variables that are available in a spatially continuous fashion across the region. Logistic regression is similar to multiple regressions. However، the primary difference is that the dependent variable in the logistic regression is sampled as a binary variable (i. e. presence، absence of landslide). The logistic regression therefore models the probability of presence and absence given observed values of predictor variables. However، with logistic regression، the researcher is predicting a dichotomous outcome. This situation poses problems for the assumptions of (OLS) that the error variances (residuals) are normally distributed. Landslide hazard assessment is a primary tool to understand the basic characteristics of the slopes that are prone to landslides especially during extreme rainfall. In this study، the coefficients obtained from the model indicate the distance to fault variable as the most effective factor on the Watershed landslide events. Based on the layers normalization and the coefficients obtained، zonation of the landslide event risk was done in five categories: very high، high، medium، low and very low. These zones percentage is respectively 28. 19، 44. 64، 18، 6. 86 and 2. 33 of the total Watershed area; that 72. 83 percentage of the Taleghan Watershed area is located in the high and very high risk categories. Landslides cause enormous loss of life and property damage in the Taleghan watershed. Assessing landslide related hazard with only limited background information and data is constant challenge for engineers، geologists، planners، landowners، developers، insurance companies، and government entities in the watershed. Accurate prediction of landslide hazard is difficult because of the complex landslideprocesses and the human activities that constantly reshape the Earth’s surface. Thispaper illustrates the application of a logistic regression modeling technique for modeling landslide probability thata detailed landslide susceptibility map was produced using a logistic regression method with datasets developed for a geographic information system (GIS). This model is careless about the distribution pattern of the independent variables. Most of the topographic factors don’t have normal distributions. Therefore، logistic regression model could get better results comparing other mathematic models. The results of the model was obtained best fitting function to describe the relationship between influencing factors (independent variables) with a landslide event (dependent variable) and the zoning in study area. The effect of each independent variable on the landslide was assessedfrom the same coefficient in the logistic regression function.

Dominant process in arid and semi-arid region is dynamic of wind that carries the sand and caused damage to several facilities and human settlements. There are many human settlements with low population and mostly small and scattered in different parts of Foothills of Dasht-e Lut (Lut desert)، especially in mountainous margins of alluvial fans. Residential and cultivation area of this settlements are mostly affected by sand movement and over time a very large impact of this move are accepted. This study tries to examine the risk assessment of the sand dune movement at Hojjat Abad village located on the west of Lut desert (East Shahdad). Study area is located at Kerman province in the West of Lut desert and East of Shahdad City. In this study، descriptive analyses were used base on fieldwork and librarian study. At first، study area confined with satellite imagery. With three days fieldwork all parts of Erg were studied. Also different parts of Hojjat Abad village that by sand، were observed and area that invaded by wind and sand were identified. For identification of wind regime and the direction of sand movement، wind data were collected from synoptic station of Shahdad. In this study for comparing of Erg movement during the times، aerial photographs from different time were used. Aerial photos of 1:55000 (1955)، 1:20000 (1969)، 1:4000 (1998) and Google Earth image (2009) were used for determination of Erg displacement during 54 years. According to above mentioned، aerials photographs and satellite images، area and displacement of Hojjat Abad Erg was measured. At the next step، using ArcGIS software، shifting and other morphometric characteristics of Erg were measured in the different period of the time. Finally، based on population data of the village in different census، population growth and diminish were analysed and compared with displacement of Hojjat Abad Erg. Based on periodic diffrent aerial photographs and Google earth images، Results shows the changes and displacement of Erg Between 1955 to 2009. In fact، Displacem of Erg was accompanied with changes of area in Hojjat Abad Erg during the 54 years. At the first stage in 1955، area of Erg was 237 ha and about 13 years later، the area of Erg increased to 245 ha. Therefore، we encounter to eight ha increase the area of the Erg. At the second stage between 1969 and 1998 the area of the Erg increased from 245 to 293 ha، (46 ha increase of Erg area). At the third stage between 1998 and 2009، the area of the Erg increased about 22 ha. Overall، between the first stage in 1955 and the final stage in 2009، area of Hojjat Abad Erg increased about 78 ha. In the other hand، Increase of area of the Erg was accompanied with displacement of the Erg to the south east of the region. According to the measurement، 1050 meters displacement accrued during 54 years، between 1955 and 2009. Between 1955 and 1969، displacement was 350 meter and between 1969 to 2009 displacement was about 700 meter. In the first stage، the Erg displaced from 550-meter distance from Hojjat Abad village to 200-meter distance. In the second stage that covered 29 years، Erg passed east of village، affected and harmed the cultivation area around the village and some part of residential area. This has led to a large volume of agricultural land of Hojjat Abad village affected by sand movement and buried under the sand، and consequently the area of habitat was reduced. Results of the study of population of Hojjat Abad village shows that during the period from 1955 to 1375 census، the population shows an ascending mode and from this year onwards there is descending mode due to sand movement and risk Erg displacement. In fact، frequency، direction and intensity of prevailing wind and sand transportation from north west are most important reason of Erg movement to the south east in this area. Table 1 Displacement of Erg in the period of studyScale Area (ha) Displacement (m) Year1:55000 237 - 19551:20000 245 350 19691:4000 293 700 1998- 315 - 2009 In this study، we investigate the sand sea displacement and risk of sand movement in Hojjat Abad region near the Shahdad city and West of Lut Plain (Lut Desert). Our study shows that the study area has been encountered with sand movement for many years. Especially in recent year with invaded of Erg to near of Hojjat Abad village، some cultivation area buried by sand and caused the migration of people from this village to other areas. Aerial photos from different periods of time and satellite image of 2009 shows the displacement of Erg from north west to the south east of the region as well as increasing of area of the Erg from 1955 to 2009. Results show that the village did not affected by sand movement during 1955 to 1969 but the Erg approached to 200 meters distance from the village. In the second stage، sand movement covered part of agricultural area of the village. In the third stage، sand effected some part of residential area of the village and cultivation area and Erg passed from east of village. Results of population census show that until 1996 population in Hojjat Abad village increase while from this time، population decrease. In fact، main reason for population decrease is sand movement in this area and damage of cultivation area by displacement of Erg. In feature two methods of live or biological and none live methods or mechanical methods can be used to prevention of sand movement to the residential and agricultural part of this area.

Iran is located in a semi arid region of the world. In recent years، dramatic changes in the form of increasing in maximum temperature and severe droughts have damaged water resources، local forests and agriculture. In the mid- and high latitudes of the Northern Hemisphere the warmest years have been recorded in recent decades (IPCC، 2007). In order to fully understand the climatic fluctuation in each region and its effect on regional ecosystems، long time monitoring of climatic parameters is necessary. Using these gathered data and different methods and modeling، the regional climate change can be studied. Establishment of meteorological stations in Iran dates back not longer than 1950s. To face this challenge، indirect evidence of past climatic situation which is recorded in some living and non living structures can be used. Tree rings are annually resolved natural archives that provide proxy data for palaeo-environmental studies and reconstructions of various climate elements. Despite of long-lived tree species in the north and the west of Iran، unfortunately dendroclimatology studies are still scare in the region. The Zagros Mountain range in the west of Iran contain the largest oak woodlands in the country and these trees are the most abundant and important species in the Zagros forests. In addition، one of the most important sites of Quercus infectoria Olive is located in Kermanshah province. The relatively high longevity of these trees and their wide distribution make them potentially suitable for dendroclimatological approaches. Our aim is to reconstruct variability of maximum temperature in Kermanshah province based on oak tree rings. Faryadras site is one of the largest sites of Quercus infectoria Olive in Kermanshah province، western Iran. The region is a part of the central Zagros Mountains. In the region، precipitation usually falls during an eight month period from October to May whereas there is no effective precipitation in other months during a year. We extracted 20 cores from 10 trees at breast height using an increment borer. Only the largest diameter trees with no obvious injury or disease were sampled. The samples were mounted on sample holders، coded، air dried and measured from bark to pith with a LINTAB5 measuring system at a resolution of 0. 01 mm using the software package TSAP-Win. All growth curves were cross-dated by visual and statistical tests (sign-test and t-test) using the software package TSAP-Win. The raw ring-width series were standardized to remove biological growth trends as well as other low-frequency variations due to stand dynamics. We decided to use residual chronology (RC) were constructed with the ARSTAN program. The reliability of the chronology was evaluated by the expressed population signal (EPS; Wigley et al.، 1984). Meteorological data for our study were available from the climate stations of Kermanshah (33°21’N، 47°09’E; 1318 m a. s. l.). We used Monthly and seasonal maximum temperatures from pervious January to current September of the meteorological station to calibrate the ring-width_ climate relationships during the common period 1951–2010. To assess the temporal stability of the climate calibration model، the instrumental data (1951–2010) were split in half (1951–1980، 1981–2010) for calibration and verification tests. Due to high correlations between the site chronology and instrumental data، a linear regression model was used to reconstruct past maximum temperature variations. Statistical tests (sign-test and t-test) showed that all of the growth curves have the same trend in the Faryadras site. The length of the chronology is 305 years (1705 – 2010)، the first year with EPS >0. 85 was found in A. D. 1840. Quercus infectoria tree rings show the high sensitivity to maximum temperature and maximum temperature is one of the limiting factors of the tree growths in Faryadras site. Maximum temperature has a negative effect on tree growths from previous January to current September. Significant negative correlations between maximum temperature and the residual chronology were found in February، March، May، June، July (p)

One of the most important aspects of urban planning and management in Iran، is disaster planning management، because many regions of the country are vulnerable to natural disasters، especially earthquakes. Many Iranians are losing their lives each year because of this disaster. For this، Constructing of temporary housing is one of the most important steps in the process of disaster management. While the construction of temporary housing can be an appropriate response to the needs of homeless people، is an opportunity to make a fundamental reconstruction. In addition to broad social benefits، proper planning for these constructions can also reduce social costs to the vast amount. In the disaster literature، the provision of shelter and housing for victims falls along a continuum from pre-disaster emergency sheltering to permanent re-housing، which are classified into three or four groups. The three categories that are usually arrayed along this continuum include emergency shelters، temporary housing، and permanent (or replacement) housing. There are two different approaches for the temporary housing of three-step (emergency shelters، temporary housing، and permanent housing) or a two-step (emergency shelters and permanent housing) process. Select two or three-stages approaches due to the situation is different. This paper is seeking to apply the Analytic Network Process (ANP) and Geographic Information Systems (GIS) to locate temporary housing sites in Municipality of Region 16 in Tehran Metropolis. Thus، three-step approach to living individuals has been chosen. Because the people who are living in temporary housing provide the time required for reconstruction principle. Methods and Materials: The Analytic Network Process (ANP) is considered as the One of the newest methods in Multi Criteria Decision Making process that nowadays be widely used in the field of scientific researches. This method has been proposed by Thomas. L. Saaty. He stated that ANP is an essential step in the decision-making process considering its reversible structure. This stage، with all of its pros and cons، was a missing step in the decision-making process. The traditional approach acted imperfectly because of its linear structure. Thus، the most important distinction between this method and AHP is the efficacy and effectiveness of criteria on each other and the analysis on nonlinear relations and internal and external relationships and interrelations between the criteria and indicators of. In general، the locating temporary housing centers are complex issues which include several variables and criteria. Therefore، Multi Criteria Decision Making (MCDM) can be used for measuring the importance of effective factors on locating activities temporary housing as one of the most appropriate methods. There are different steps for applying this method. Therefore، this technique and its main steps are introduced. First، making a model and a structure in which the subject matter is clearly stated and is analyzed within a logical system such as network. This network structure can be regulated and formed by decision-makers and through methods such as brainstorming or mathematical techniques like DEMATEL. The second step includes the formation of comparison binary matrix and extracting the priority vectors. This step is similar to the Analytical Hierarchy Process. Finally، the third step consists of forming the Meta-Matrix. Then the article introduce the variables affecting the field of housing and shelter after disasters (24 index and in the 4 criteria)، as it has pointed to use this model in the study (16 in Tehran). Results and The results of findings show that among the indicators studied; three indicators per capita service levels، possession costs and the present land use were the most important variables، and the three indicators adjacent to the passageways and road networks، polluting industries and strong power boundary were the lowest importance in the process of selecting locations for habitation to homeless people in the related to the decision making from the perspective of planners itself. In addition، according to the method and the selected indicators have been identified the Beesat and 22 Farvardin parks as the most appropriate locations for establishing the temporary housing sites.