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Said Balyani, Yones Khosravi, Alireza Abbasi Semnani,
Volume 3, Issue 4 (1-2017)
Abstract

Hazard is potential source of harm or a situation to create a damage. So identification of zones exposed to hazards is necessary for planning or land use planning. But this situation becomes more critical when they appear at the population centers. So applying the principle of passive defense based on environmental capabilities is unarmed action that caused the reduction of human resources vulnerability, buildings, equipment, documents and arteries of the country against the crisis by natural factors such as drought, flood, earthquake, etc. Considering the possible occurrence of such risks in population centers, ready to deal with what is known unpleasant and undesirable consequences is necessary. On this basis and given the importance of population centers in Helle and Mond basins, in this study, the authors tried to analyze the Rain hazards of drought and flood.

The study area,Helle and Mond basins, with about 21,274, 47653 km2 area, respectively are located in the south of Iran. The Helle basin approximately is between 28° 20'N and 30° 10'N latitudes and between 50° E and 52° 20'E longitudes and Mond basin is between 27° 20' and 29° 55' latitudes and between 51° 15' and 30° 27'E longitudes.These basins are located in sides of a massive sources of moisture, Persian Gulf.

In this study, data from 23meteorological and synoptic stationsstations, during aperiod of20 years (1992-2011)in northern region of the Persian Gulf (Mond and helle basins)were used to calculate Standardized Precipitation Index (SPI). The data were collected by the Iranian Meteorological data website (http://www.weather.ir). The SPI is primarily a tool for defining and monitoring drought events. This index may be computed with different time steps (e.g. 1 month, 3months, 24 months). The SPI is defined for each of the above time scales as the difference between monthly precipitation (xi) and the mean value ( ), divided by the standard deviation. To assess flood risk zones, the flood, annual evapotranspiration, cities and populations centers layers were collected in Helle and Mond basins position. The annual precipitations and the SPI maps were drawn by Geostatistics, Kriging. It also the flood and annual evapotranspiration layers were weighted by Euclidian distance method, separately. Finally, all layers are weighted by AHP and fuzzy-linear methods (descending and ascending linear function) into vulnerable layers. The final map of vulnerable areas with flood and drought high risk was drawn based on the algorithm of linear-Fuzzy in a raster format.

According to the results, eastern, north eastern and south eastern part of Mond basin had high annual precipitation. Based on this result, it said that these parts of study area were known the least dangerous areas of vulnerability. The results also showed that with passing of the western regions and going to the center of the study area the annual rainfall have been added over the years. Kazeron, Chenar Shahijan, Firouz Abad, Borm plains and some parts of Khane Zenyan and Dash Arzhan are cities located in this regions. Low latitude, Proximity to the warm waters of the Persian Gulf, low annual precipitation and high temperature causing evaporation and inappropriate environmental conditions in Boushehr province and some coastal cities such as Genaveh, Deilam, Boushehr, Baghan, Lar and Khonj. Accordingly, west, north west, south and south west regions in Helle basin were located in extreme vulnerability zone with a loss of annual rainfall for drinking and agricultural production and poor nutrition underground aquifers.


Alireza Hosseini, Hediyeh Akbari Ghamsari,
Volume 3, Issue 4 (1-2017)
Abstract

Classifying daily climate circulation patterns has always been considered by climatologists. Investigating climate changes such as rainfall and the temperature in a same single time and place suggests that these changes are strongly influenced by atmospheric circulation patterns.

Regarding so, climate changes, known as variables here, such as rainfall, temperature, and other related phenomena, which are exemplified as flood, drought, glacial, and etc. are associated with special types of climate circulation patterns. The continuity and alternation of the systems are classified or identified climatically, therefore weather classification system is one of the main objectives of the synoptic climatology (Huth, 1996). Since every weather type creates its own special environmental condition, lack of identification in weather type frequencies leads to a difficult environmental explanation and alternation (Alijani, 1380: 64).

Identifying atmospheric circulation patterns different things that can be expressed inductively such as frequency, intensity, and spatial distribution of climate changes in rainfall and its physical causers (VicenteSerrano and LopezMoreno, 2006).

Heavy rainfall in many watersheds, particularly in the basin and sub-basin which involve less time exposure, causes floods and it also damages human, natural resources, infrastructure utilities and equipment. Before the occurrence of this kind of rainfall, it requires a deep understanding of the synoptic systems of their creator. This understanding is only possible through the classification and identification of rainfall patterns which used to cause floods in the studied basins.

The present study also aims at identifying and classifying the synoptic patterns of rainfall during the statistical stage of the study in the basin which caused flood in Taleqhan basin.

Taleqhan basin with area of (65/1242) per square kilometers is located in "36֯, 5', 20" to "36֯, 21', 30" north latitude and "50֯, 36', 26" to eastern longitude "51֯, 10', 18".

The study area is 120 kilometers away from North West of Tehran and located in a relatively high mountainous area in Alborz Mountain. This area is ranging from 1700 meters to 4400 meters above sea level. Average rainfall in this basin ara is 515/16 mm and its annual temperature fits 10.5 centigrade.  About 79 percent of rainfalls occurs from the cold weather period in November to March. It is also know as semi-humid cold weather based on the De Martonne classification.

Circulation algorithm (CA) and pattern clustering algorithm (PCA) were determined based on the daily methods in synoptic scale by applying information from stations in Taleqhan basin (Gateh deh, Dehdar, Dizan, Snkranchal, armouth, Ange, Joostan, Zidasht). In order to classify the weather type, daily average rate of 500 HPa and the sea level pressure (SLP) were extracted and reconstructed over the period (1980-2011) at the 2.5 degree of NCEP. Selected range includes 608 points from latitude of 10 to the 60 of northern degree, and latitude of 10 to 80 of eastern degree.

Principal components method mixes the interrelated points and reduces the matrix size, so 13 main components are remained that they includes 93 percent of the total variance. This study employs S array and Varimax rotation to identify different types of weather. It also makes use of K-Means clustering method to classify daily weather types. And finally, a matrix was formed in 118×608 dimension for 118 common days of rainfall among stations. All days were divided into four groups. They offer the most common climate circulation patterns in the proposed area. At the end, and finally integrated maps of sea level pressure and 500 HPa were drawn for each weather type. 

According to the results from factor analysis, 13 main elements were selected that they included 93% of the total variance of the data. According to the above mentioned method, all days (118 days) during the statistical period (1980-2011) were divided into 4 groups which provide the most climate circulation patterns in the study area. Then, integrated maps of sea level pressure and 500 HPa range were drawn for each of the types. Clusters were numbered according to the K-Means arrangement, and they were named based on the pressure patterns and the way circulation lines were ordered.

The classification shows two different resources for rainfall in this basin.

A: Those rain systems that are entered to the country from the West and South affect this basin. These systems humidity are caused by the Red Sea, the Mediterranean sea, the Black Sea, and the Atlantic Ocean. (B) Some parts of the Caspian coast rainfalls and the northern part of the Alborz mountain that has received their humidity from the Caspian Sea and it has infiltrated northern high-land, causes the rainfalls. It enters the basin from the wide valley of Sefid Rood. According to the rainfall measuring stations data, the least rainfall area is in western, which includes low-land areas. And the most rainfall area is its northern east. Rainfall in this area, in terms of rainfall time distribution in a year, is the Mediterranean. It does not involve a complete dry climate in summer and it takes 3 to 4 percent of the total rainfall.  Rainfall in the basin, respectively, is distributed in winter, spring, fall, and summer.


Miss Elham Karegar, Javad Bodagh Jamali , Abbas Ranjbar Saadat Abadi , Mazaher Moeenoddini, Hamid Goshtasb ,
Volume 3, Issue 4 (1-2017)
Abstract

Dust particles are important atmospheric aerosol compounds. The particles are resulting performance of strong winds at the soil surface desert areas. Sources of dust are 2 types: 1- Natural Resources 2- Human Resources. Iran is located in the desert belt which this problem cause increased the frequency of dust storms, especially in South East (Sistan) and South West. China Meteorological Administration Center classifies storms based on particles type, visibility and speed storms to 4 kind: Floating Dust, Blowing Dust, Sand/Dust Storm and Sever Sand/Dust Storm. In general, the effects of dust storms in 7 of Environment (particles into remote areas, the effect of dust particles on the material, climate, oceans and deserts), public health and health (increase of respiratory diseases , cardiovascular problems, digestive, eye, skin, reduced hearing, infections, reduced life expectancy and premature death, etc.), economic (unemployment, road accidents, damage to communication lines, air, land, sea, increase water turbidity in water utilities, creating uncertainty for all economic activities, etc.), Agriculture and Livestock (negative effect on the growth of plants and animals, reduced productivity and diversification, intensification of plant and animal pests and diseases, rising costs maintenance of livestock, etc.), socio-cultural (poverty and the loss of local jobs, destruction of subcultures, rural migration to the cities, closure of educational premises, industrial units, services, etc.) and military-security (disabling weapons, food and beverage contamination, the threat of sensitive electronics and power transmission systems, and reduce the useful life sitting on warehouse equipment, logistics cargo weight gain, etc.) can be evaluated. One way to identify, evaluate and forecast dust storm modeling. Dust cycle consists of 3 parts, dust emissions, dust and subsidence transfer dust that can be simulated by models.

In this study using the WRF_Chem model with FNL[1] input data and GOCART schema, sever dust storm in Sistan region was simulated to date 14 & 15 July 2011. Satellite images of the event was received by the MODIS sensor. Dust concentration data was received from the Department of Environment. The dust storm code, minimum visibility data and maximum wind speed data was received from the, Meteorological Organization.

The results of the simulation for dust concentration which peak amount of dust was for 21Z14July2011 and 03Z15 July 2011. Model output showed maximum wind speed 20 m/s with North to South direction in the study area. The model predicts maximum dust concentration for the latitude 31 degree North and longitude 54 degree East to 66 degree East (Within the study area). MODIS sensor images showed clearly the sever dust storm. Simulated time series in Figure 3-1 Changes in dust concentration during the event show in the Sistan region. As can be seen from the peak of the concentration of dust in 21 hours on 14 July (350 micrograms per cubic meter) and 03 hours on 15 July (425 micrograms per cubic meter) 2011 was created. Model simulation and satellite images indicated which the Sistan region, especially dry bed of Hamoun wetland in East of Iran was main source of sand and dust storm. Also, based on the model output blowing wind direction from North to South on Iran which converging these currents in East Iran caused by strong winds in the lower levels (According to the meteorological data), arise dust, increasing the dust concentration (According to Department of Environment data), increasing the dust and being transferred to the Southern regions, especially  Oman sea. To identify the source of the sand and dust storm, the path of the particle and anticipated this event cant actions and warned to stop and reduce effects its. . Simulation of dust particles in the resolution of 10 and 30 kilometers, the plains of Sistan in Iran's East region as the main source screen. The findings suggest that compliance with the maximum concentration limits on known sources of particles (especially Sistan plain dry bed of plain wetlands) is. Check drawings wear rate showed that the source of dust in the Sistan region, particularly the high potential of our wetlands dry bed of soil erosion in wind activity 120 days during the hot and dry conditions, and silt and clay up to thousands of kilometers away from their source transfers. Vector lines on maps wear rate, indicative of converging flow north-south and severe dust storms in history is this. It is better than models forecast dust events and rapid alert


[1] Final Reanalysis


Abolfazl Ghanbari, Fariba Karami, Mohammad Ali Saleki,
Volume 4, Issue 1 (4-2017)
Abstract

One of the geomorphologic issues that many human activities affect is the landslides. Natural factors and human activities on the other hand, these events are triggered. Landslide one of the most active hazards are natural processes that lead to erosion and changes in the landscape. Iran is a predominantly mountainous topography, seismic activity and high landslide, diverse climatic and geological conditions of natural conditions for a wide range of slip is important. Located in second place in the sector of industry, population of 1695094 people, proximity to major faults of Tabriz and occurrence Landslides of different city of Tabriz, the city has become one of the most dangerous cities in the environmental hazards, especially landslide. In these circumstances and completed a comprehensive review and a detailed zoning of land for landslide susceptibility seems absolutely necessary. The purpose of the present paper, the occurrence of landslide susceptibility assessment and mapping potential occurrence of landslides in the city of Tabriz in this range.

     This research of the type applied- development research and of the research method is descriptive - analytic. In this study, using a variety of sources including satellite imagery, aerial photography, global positioning system (GPS) and field studies landslide occurred in the study area were identified and these data were analyzed using the software ILWIS and use of library studies and expert opinions should identify the criteria and sub-criteria and range were classified. Then, using fuzzy TOPSIS model, the importance of the criteria and sub-criteria specified in pixel units and finally combining fuzzy-TOPSIS model and overlapping functions in ARC / GIS final map was extracted.

Geomorphologic and lithology conditions of the city with its mountainous location where the trigger landslides. The final results indicate that over 30% of the areas of the city of Tabriz are medium to high risk that this areas of land in the north and northeast is sparse. The accuracy of the final map and the map of the distribution of faults and the accuracy of the study proved to be that hazardous zones roughly corresponding to the final map lapses occurred. So we can conclude that the method and the model presented in this paper is an effective method for landslide hazard zonation within the cities.


Bakhtiar Mohammadi, Mohammadhossien Gholizadeh, Sharifeh Zarei,
Volume 4, Issue 1 (4-2017)
Abstract

Climate and weather conditions are among the most important factors in controlling our daily and even long-term activities. Since the emergence of human beings, the weather has been effective in our lives. Changes in precipitation and temperature, solar radiation and other climatic parameters, have had so much impact on people’s lives that as far back as the first periods of human lives, we have been witnessing the climate change, and these factors have determined the way of our lives. Since the old days, the scientists of criminology, sociology and psychology have considered the influence of nature and different circumstances on the crime and its rate. Hippocrates and Montesquieu were the oldest ones that studied about the impact of climate on effects and aggressive behavior. The main objectives of this research are as follows: Understanding the climatic regions of Kurdistan Province, and assessing the relationship between the climatic regions of the provinces and the aggression rate. From a psychological perspective, aggression is a behavior whose aim is to harm others or oneself with a conscious intent. The main idea of this study is to consider the theory that whether there is any connection between natural factors, especially the weather, and the mood, temperament and the aggression rate of people. For this purpose, and for climatic zoning of Kurdistan, we have used the surface data of all synoptic stations in Kurdistan as well as the stations around the province from their establishment until 2005 (25 stations). Using these data, 2068 cells (with approximate dimensions of 7/3 * 7/3 km²) in Kurdistan were appraised every day according to the Kriging interpolation. By applying the cluster analysis to these data, two main climatic zones were identified in Kurdistan. The hot-humid region was including the cities Bane, Marivan, Sarouabad, Sanandaj and Kamyaran, and the cold-dry region, was including the cities Saghez, Diwandareh, Bijar, Ghorveh and Dehgolan. Then in each of these regions, in the number of the samples which were obtained through Cochran formula (768 samples), the Buss and Perry questionnaires were distributed and collected. The new version of the Aggression Questionnaire, whose previous versions was hostile questionnaire, was revised by Buss and Perry (This is a self-report questionnaire that contains 29 words and four subscales).The prototype questionnaire has 52 questions, but a lot of weak questions of the questionnaire have been excluded using the factor analysis method, and it has turned into a questionnaire with 29 questions. Finally, the results of the questionnaires were analyzed through SPSS, using the t test for the independent groups. The results of this study indicate that the physical and verbal aggression rate and the level of anger and hostility among the residents of the cold regions of Kurdistan are higher than the residents of warmer regions. The results also showed that the level of aggression among the men is higher than women. The aggression among the men mostly appears in a physical form, while women make it in its verbal form. Also, in the hot-humid areas, the level of anger and hostility among the women is more than men. According to the data analysis, we can say that the results of this study are consistent with the findings of some researchers, though in some cases the results are not consistent with other researches. The assessment of the geographical environment has not concerned the scientists alone, and philosophers like Ibn Sina, Sociologists like Ibn Khaldun, and writers and thinkers such as Al-Jahiz have looked at geographical factors from other perspectives, and have examined its relationship with ethics and human behaviors. In conclusion, we can say that the results of this study are non-aligned with the results of the studies that have examined the effect of weather conditions on the temperament or real aggression. But the results of this study are consistent with the researches that have investigated the potential of aggression. Therefore, we can say that in a short period of time, warm weather conditions can predispose one to aggression, but to live in the warm climates, may raise people`s patience at the end, and make them able to control themselves at the occurrence of aggression. The results of this study indicate that in Kurdistan province, the extent of potential aggression is higher among the residents of the cold regions (Saghez, Diwandareh, Bijar, Ghorveh and Dehgolan) than the inhabitants of the tropic ones (Bane, Marivan, Sarouabad, Sanandaj, and Kamyaran). To justify these findings, we can say that freezing creates a sense of insecurity in people because we experimentally see that the residents of a cold region need to work constantly in order to keep their bodies warm. They need to have a secure plan for the winter, so that they can make enough food, fuel and clothing. This coherent planning makes them more active in comparison with the residents of the tropical regions. An unfavorable and difficult living environment emboldens people. The people who belong to these areas are pragmatic, and their approach to the environment is competitive or aggressive. In contrast, the people who live in the relatively warmer climate have usually less activity. The property of this kind of temperament is laziness and inertia. Working in hot places is unpleasant because it makes people sweat, and it makes them tired soon. Another finding of this study is that in the whole province, in both cold and warm climates, the aggression among men is more than women, and this difference is greater in cold areas. The men spend most of their time outside the houses, and because of this, the effect of climate is more on them, but women are living most of their time at home, and they can take advantage of the air conditioning equipment. Thus, they have a more relaxed and flexible temperament.


Morteza Esmailnejad, Bohlol Alijani,
Volume 4, Issue 1 (4-2017)
Abstract

Climate change is one of the crucial factors, which threaten many sector such as agriculture, water resource for decades, and the sector is more sensitive to climatic conditions.  Communities are the most vulnerable to the adverse impacts of climate change and variability because of their low adaptive capacity. One of the challenges of climate change and human spatial dimensions of climate change in international borders where climate change, and creates special challenges. Populated places in the East where rapid urbanization, industrialization and agricultural intensification result in vulnerability to climate change, water shortages as the main concern arises.

 Adaptation to climate change is the adjustment of a natural or human system to moderate the impacts of climate change, to take advantage of new opportunities or to cope with the consequences. Trying to identify the attitudes of people and their mental models of climate change can provide application to manage the post-change. Culture and engineering modeling approaches minds of scientists for climate risk management and climate change consequences have adopted. The review focused on farmers’ perceptions on changes in temperature, precipitation (rainfall), adaptation measures taken by farmers, barriers inhibiting these adaptation measures and the socioeconomic determinants of adaptations to climate change in Sistan plain.

The aim of this study is to provide mental system model, and understanding of climate change is to adapt these areas. To carry out this study to develop a theoretical framework for the model to adapt to climate change was discussed in Helmand. The field study was to assess the views of people on climate change action. The review found out that most farmers in this region are aware that the continent is getting warmer, and precipitation or rainfall patterns have changed. People with new changes and features adaptive approach to the challenges ahead were investigated. This data is based on knowledge (awareness) of water and climate change adaptation and mitigation strategies and be ready. So how compliance action is preventive in nature and to reduce the repercussions of climate change and the potential benefits of a region in the face of these side effects are formed. Most respondents aged over twenty years are at least a decade to climate change are felt to be most frequent subjects 30 to 40 years old. The data collected were processed using statistical techniques and modeling for ranking and evaluation of adaptation strategies were created and ASI index. The results for the insights, policy makers and service providers for local development is important, and can be targeted measures used and the promotion and adoption of coping mechanisms with the potential to build resilience and adapt to climate change and the resulting effects environmental prepare.

The results showed that most people in the region following the election of climate change is adaptive behavior. In total, there are 15 strategies in the region. The ASI index rating of strategies to change the pattern of cultivation, selection of resistant strains, reducing the amount of land-cultivated variety is the pattern of adaptation to environmental changes. Ensuring awareness of and adaptation to climate variability call was conducted with the cooperation of the people. Therefore, variability of climate and natural features of the area was measured by various options. The results show that already sampled respondents in the community are aware of climate change. 60% of respondents strongly observed signs of climate change and the dry season and low rainfall and warmer temperatures to believe. The main adjustment options adopted by farmers to temperature in the region include change of product types and number of ships that 61.6 percent of the farmers that their efforts. Another priority is that 39 percent of them tend to change sowing dates and planting varieties resistant to drought. The main recommendations for adapting to new circumstances in this region to stimulate the economy and livelihood of local people can be to diversify crop production (food for example, and cash crops, annual and permanent crops greenhouse) and the use of foreign income from farm sources (ecotourism, rural tourism) can be cited.


Norollsh Nikpour, Samad Fotohi, Hossien Negaresh, Masod Sistani,
Volume 4, Issue 1 (4-2017)
Abstract

Has been stated in various sources, soil as one of the most important natural resources has a major, role on the lives of humans. Today soil erosion and sediment production, a problem that is increasing day to day process and loss of surface soils and sediment accumulation in dam reservoirs, canals and also sedimentation damage to the country's economy. One of the most important types of water erosion, gully erosion or (Galli formation). This type of erosion and loss of soil due to sediment production and enormous damages to land, roads and infrastructures, is of great importance. Soil erosion is one of the most important factors that threatens large areas of Iran annually and decreases or eliminates the quality of agricultural lands and rangelands. Due to highlands of Iran in comparison with the grounds and surrounding plains (mean elevation of 1250 m), it has been affected by water erosion. So it is very important to study erosion and present management strategies to reduce the impacts of erosion in basins of Iran. This study to Target morphometry gullies and the influencing factors on gully erosion in the South West sub-basin of ILAM (Cham Fusel).

The average height in the area between 50 and 1,200 meters above sea level and has a dry climate with an average annual rainfall of less than 200 mm and the average annual temperature is above 25 degrees C°. In terms of the main geological formation of this area is affected by gully erosion, Aghajari formation (red mudstone, siltstone and sandstone) are related to Miocene period. Basin area of over 150 hectares affected by gully erosion and slope threshold for gully erosion in the area between 8-2 percent.

The research method in this study is field research, library study and morphometric measurements of gully erosion forms. Besides, on the basis of the geological maps of 1/100000 and topographic 1/50000 and DEM 30 meter area, the software of GIS Arc has been used to make the required maps. Furthermore, the GPS device and a camera has been used in the field to harvest. o

The average height in the area between 50 and 1,200 meters above sea level and has a dry climate with an average annual rainfall of less than 200 mm and the average annual temperature is above 25 degrees C°. In terms of the main geological formation of this area is affected by gully erosion, Aghajari formation (red mudstone, siltstone and sandstone) are related to Miocene period. Basin area of over 150 hectares affected by gully erosion and slope threshold for gully erosion in the area between 8-2 percent. The study, which the sub basin in Cham Fusel ILAM province is located in the South West, with the aim of gully morphometric including deep, height, length, height from sea level, and geographical location as well as classification criteria in three sample gully gully of area, In order to identify factors affecting the development of erosion in the basin plain Cham Fusel was evaluated. The results of morphometric and field visits to the region, factors such as climate factors, slope and aspect, geology (Land genus), tectonic activity and faulting, land use, overgrazing of amount plants, including the most important factors recognized were identified in the development of gully. Which layers to extract some of these factors in Arc GIS software designed and based on creation of maps and data to analyze each of these parameters and their impact on Gully Erosion percent has been paid.

According to the morphometric data, it can be concluded that the gullies basin largely toothed and clawed, permanent, of medium to large gullies, which have expanded continuously. Below you can see images of morphometric gullies sample was collected during the field visit of the area. The results show that due to the widespread earthquake in the region in recent years and local faults can be concluded that one of the most important factors in the formation Galli uplift of the Earth. Also overgrazing by cattle ranchers in the area Tuesday Abdanan city, murmury, Dahlgren and ranchers outside the province of Hamedan and Kermanshah provinces such as ranchers who use the area as Qishlaq, Another important factor in the development of gully erosion in the area. Due to the climatic amount of rain, sleet, snow, ice, temperature and wind could be the climate factors in the rise of water erosion. As the geographical location and local climatological data suggests, the study area is influenced by the Mediterranean winter rains. Which are imported to Country from the West in winter and more in the form of showers and hail rainstorm conditions caused severe erosion gully in the area easy. Lack of growth of vegetation and bare Land is another contributing factor is considered in the development of gully erosion in the area. That is because the rainy season in the winter when the soil in the area is almost devoid of vegetation. The lack of vegetation in the region as one of the important factors, has caused soil erosion, its most destructive erosion of the gullies show. Also according to the map slope and aspect of the region was marked within the range of between 2-8 percent and Create Gully and aspect with the West and the South West and North West are more affected by gully erosion. Finally, all factors except factors of land use, all other factors were named among the important factors affecting the development of gully erosion are the region. It was also found other factors in the evolution of land use contrary to gully erosion region. That is because of the lack of culture in this area and dropping land by farmers as wasteland, and also because of the recent drought in the region has caused more and more extend of gully erosion and land with the ability crop damage and destroy all. The results obtained showed that the study area in terms of of gully erosion in critical condition.


Elahe Etemadian, Reza Dostan,
Volume 4, Issue 1 (4-2017)
Abstract

Climate risks are the inherent features of Earth's climate. The occurence of heat wave is one of these natural phenomena. Heat waves, one of the basic appearances of climate change, are very important because of frequency and damage of life and property, (Haddow et al, 2008). Frequency of heat wave occurence in recent years, is one of the aspects of climatic changes and extreme weather (Matthies et al, 2008), and resulted in heavy financial loss and increasing p mortality. From statistical point of view, heat waves are the positive changes and upper extremes of maximum average daily temperature, which continuing during consecutive days, weeks or months in certain geographical areas. According to the available definitions, two dimensions of time and space are important in the occurrence or non-occurrence of heat waves  (Smith,2013). Due to the positive slope of temperature and increase in temperature extremes and many changes in values of maximum temperature in Iran, main purpose of this study is the spatial and time distribution of heat waves on the plateau of Iran.

The daily maximum temperatures recorded in 49 synoptic stations of 31 years (1980-2010) climate normal period were used for the spatial distribution of heat waves. In order to determine heat waves, using the 95th percentile index, the temperature threshold for each month and each station was determined separately. The reason of studying heat waves in the monthly scale is temperature differences and different consequences in different parts of Iran, as an example, maximum temperature 30 degrees in May for south of Iran is normal, but for the northern regions of Iran is a heat wave and causes damage. So the basis in this study is determining heat waves and spatial differences of these phenomena in monthly scale. In this study, the heat wave has been defined as temperatures above the 95th percentile threshold per month, continuing for three days and more. So with specifying the threshold temperature for each month at each station in different parts of the country, temperatures above the threshold continuing for three days and more, defined as a heat wave for each month and the spatial distribution of heat waves was plotted in the whole area of Iran plateau for each month. In order to determine changes in heat waves in the whole country, the number of heat waves has been specified for the whole country in three decades (80-90-2000).

The spatial distribution of heat waves: Maximum temperature thresholds are related to the southeastern, southwestern and southern stations; and the lowest thresholds are northern coast and northwest mountains stations. In general, the minimum temperature thresholds are visible in the northern half and towards the heights; however, the maximum thresholds are visible in southern half. In this temperature variable, the role of latitude and altitude is dominant in lines with the same threshold of extreme temperature like other temperatures properties in Iran. Spatial variations of this temperature parameter throughout the year, increased from the Caspian Sea and North West of Iran to the South East and South West of Iran. In the entire study period, the number of heat waves in different parts of Iran indicates that most heat waves were occurred in the mountainous regions of Iranbased on the zoning temperature Alijani. The number of heat waves decreased from this area to the north and south coastal areas and East of and Central of Caspian has the lowest number of heat waves during the entire period of the study in Iran.

Time, temporal and decade distribution of heat waves: Time changes in heat waves shows increasing trend, As we can see the increase in the number of heat waves, from mid-90s and then, in 2010 most of it.Also, the 5-year average and decade-long average of heat waves, show a significant increasing trends and the most of the heat waves occur in Iran during 2000s. Time series of heat waves in Iran; show a significant increase over time.Hence, from the late 90's onwards, the spatial average of heat waves rather than the average before these years has increased. Iranian plateau in 1992 and 2010 has experienced the minimum and maximum of heat waves, respectively.

The results showed the minimum temperature threshold along the heights in northern half of the country and maximum temperature threshold at the southern half. Spatial variations of this thermal parameter throughout the year, is increased from the Caspian Sea coast and the North West of Iran toward the South East and the South West of the country. In general, this parameter that is associated with the extreme temperatures in Iran is under latitude and heights distributions the same as distribution of maximum temperature areas in Iran. But spatial distribution of heat waves as a natural hazard is different from the distribution thresholds and maximum temperatures. So that, the most heat waves are in Zagros Mountains, the East foothills of Zagros, South of Western and central Alborz and also southern Binalud foothills in the North East. The number of heat waves is reduced toward the center of Iran and the Great Plains (Lut and Kavir deserts). The minimum heat waves occur on the coasts of Caspian Sea, southern coasts of Iran, South-West and West Zagros and central Iran. The occurrence of heat waves in Iran have an average between 9 and 14 heat waves during all months of the year except for May with a maximum of 6 heat waves and June, with a maximum of 16 heat waves (months of minimum and maximum occurrence, respectively). This shows minimum increase in cold months and maximum increase in warm months. Therefore, the occurrence of heat waves in Iran is possible in warm and cold periods of whole year and there is a little difference between these two periods. This indicates both internal (local) and external factors (air masses) involved in occurrence of heat waves in Iran. The number of heat waves increase and decrease since January and June, respectively. This temporal sequence is disrupted by a sharp decrease in May (6 heat waves less than previous month).


Taghi Tavousi, Mohsen Hamidianpour, Rashed Dahani,
Volume 4, Issue 3 (9-2017)
Abstract

Thunderstorms are one of the most important, abundant and severe atmospheric hazards. In addition to destroying a large amount of agricultural products and construction projects, cause many human casualties are annually in different parts of the world (Iran Pour and et al, 2015). This phenomenon is associated with severe storms, showery precipitation, hail (Puranik and Karekar, 2004), and thunder and lightning (Nath et al, 2009). These storms occur 50,000 times on a daily Basis. They account for 18,000,000 yearly (Ahrens, 2009). Extensive studies have been conducted in Iran and the world in this regard. For example, Wallace (1995) examined the abundance of lightning in the United States using 100 stations. He concluded that the greatest frequency of convectional showers occurs early in the night and at least at midnight. Sterling (2003) described the thunderstorms as a major dilemma for the United States in the twentieth century. The environmental and economic consequences of thunderstorms and their associated phenomena such as floods, hail and heavy precipitation are believed to be very ruinous on the US economy. Sistan and Baluchistan Province, Iran has annually been witnessing a variety of thunderstorms systems and associated precipitation. The province has suffered lots of damage resulted from the phenomena caused by thunderstorms. Therefore, this article aimed for a spatial analysis and the frequency of thunderstorm occurrences at different time scales. The article also examines the temporal variations and trends. The secondary questions outlined here are as follows: At what time of day do thunderstorms occur? How are thunderstorms recorded as various codes? Which one of these codes is the most commonly reported one? In terms of location, what are the stations with the greatest and least number of thunderstorms?
The area under study is Sistan and Baluchistan Province, Iran. With an area of almost 187,502 km2, the province is located in the southeastern part of Iran, on the Oman Sea coast and in the vicinity of Pakistan and Afghanistan. The province has 300 km water border with the Oman Sea in south, 1100 km land border with Pakistan and Afghanistan to the East, Khorasan Province to the North, and Kerman and Hormozgan to the West (Ebrahim Zadeh, 2009).
In this study, the frequency of thunderstorms was extracted based on 7 synoptic stations and the used of Presence Weather Codes. Temporal variations were then studied using the Man-Kendal and Sen's non-parametric tests. Finally, the relationship between the thunderstorms and ENSO was investigated. Meanwhile, spatial dispersion was also taken into account.
The results showed that thunderstorms have a peak region in southeast part with the center of the Saravan and Iranshahr stations and a minimum area in the Oman Sea coasts (Konarak and Chabahar). More precisely, Saravan Station scored the top with 567 thunders and lightning, while Konarak Station hit the lowest point with 96 in this 30-year period. In the maximum thunderstorm region, Saravan and Iranshahr are the main centers during different seasons so that the number of thunderstorms is higher in summer and fall in Iranshahr compared to Saravan. In winter and fall, such thunderstorms, caused by extra-tropical origin, are more in Saravan than Iranshahr Station.
The results of hourly investigations of thunderstorms showed that most of thunderstorms occur at noon and 3:00 p.m. Codes 13 and 17 were the most frequently reported codes with 605 and 571 occurrences, respectively, Codes 99 and 5 were the least. Monthly investigations showed that May and March had the highest number of thunderstorms (322 and 317, respectively), while September accounted for the least number (55). Quarterly investigations showed that spring had the highest number of thunderstorms (756) followed by winter (559). These thunderstorms are seen in spring more than other seasons because of the passage of extra-tropical air masses, which is abundant in the region under study. Summer, which is the Sub-tropical High pressure (STHP) season, had the least number of thunderstorms (340 occurrences of thunder and lightning). These thunderstorms mainly occur in Iranshahr and Saravan Stations, which was proven in the spatial analysis. The summer incidence increase of the thunderstorms is rooted in the Monsoon systems, preparing the ground for the phenomenon. The temporal variations at different monthly, quarterly, and yearly scales showed that no significant differences are found in thunderstorm trends. The phenomenon has experienced enormous fluctuations, likely to be associated with complex changes of macro-climate patterns. El Nino and the Lanino are likely to be the main factors affecting the ENSO's warm and cold phases. According to the results, almost 70% of thunderstorms are associated with the El Nino. In other words, more thunderstorms are expected during ENSO's warm phase.      

Fatemeh Razzaghi Borkhani, Ahmad Rezvanfar, Syed Hamid Movahed Mohammadi, Syed Yousof Hejazi,
Volume 4, Issue 3 (9-2017)
Abstract

Agricultural development depends on increasing production and productivity and reducing risks threatening the agricultural sector and in the shadow of extension risk management that can be prevented of wasting and damage to agricultural crops and the provision of necessary domestic agricultural production, also providing export and currency-made to advance the country's development goals. Pay attention to the strategic location of Mazandaran in citrus products, natural hazards that threaten citrus production each year in the economic development, production and exports and providing sustainable livelihoods to farmers affected negatively. Agriculture and in particular the subdivision gardening, due to dependence on weather conditions, the brunt of climate change is undergoing, horticulture stable on long-term behavior growers to ensure the stability and productivity of the land in the future is created and the expectations and concerns of the community intended to provide a food healthy and security to protect the environment and natural hazards reduction is concerned.
The main purpose of this study was to investigate Mechanisms of Reducing Natural Disasters and Risk Management to Sustainable of Citrus Gardens in  Mazandaran Province. The Population consists of all citrus farmers in the villages of 12 counties of Mazandaran province, a sample of 290 farmers was selected by using proportional random sampling method among 122361 citrus Orchard men. Data were collected by means of a questionnaire. The Validity of questionnaire was determined through sustainable agriculture experts of Mazandaran County and some faculty members at the University of Tehran, Department of Agricultural Extension and Education, Agricultural Management and Development. The reliability was found to be acceptable. Diagnostic validity by using an average variance extracted (AVE) and reliability by using Cronbach's alpha and composite reliability (CR) were confirmed. To explain the mechanisms Confirmatory Factor Analysis (CFA) was used to modeling the structural equations using LISREL software, version 8.80.
According to the results of the ranking factors related to the mechanism in dimensions, "supportive - credit", "environmental - spatial", "socio-participation", "knowledge-awareness", "infrastructure-institutional "," educational –informational" and "economic factors" respectively were mostly mechanisms and strategies based on factor coefficient. Among the credit-supportive, "insurance" has had the most important role in the structure of credit-supportive factor, thus, according to the regional agricultural insurance and damages in the event that the actual performance of the target area is less than the guaranteed performance is a good solution. One of the major goals of sustainable agricultural systems is decreasing vulnerability and improving sustainable livelihoods in rural people. Therefore adoption of GAP technologies has emphasized to increase elimination of pest with minimum impact on the environment, human health and access to sustainable agricultural development, (achieve to environmental, economic and social sustainability) as well as attention to the sustainability of on-farm activities to certain safety and quality of food and non-food agricultural crops. According to the study, understanding and awareness of farmers to improve skills and farming and horticulture management techniques to reducing natural disasters and risk management and  expand the participation of farmers in risk management, to develop processing and packaging industries, convenient and refrigeration practices for storage and preservation of agricultural and horticultural crops, in addition to  communication channels network  through demonstration farms, farmer field schools, workshops, field days, meeting, SMS, and information and communication channels carried by ICT as necessary solutions recommended. This Provides Information and knowledge share among orchardist and strengthening local associations and with each other.  This process helps them to increase their awareness about mechanisms of reducing natural disasters and risk management to sustainable of citrus gardens and find positive attitude toward it. This output complete sustainability goals of agriculture through improving social sustainability.  In order to access growers to timely sales service products, the establishment of a new extension system based on an available market with up to date and secure information as Marketing Information Services (MIS) could be a suitable strategy for orchardists in order to access sustainable development.

Seyed Reza Azadeh, Masood Taghvaei,
Volume 4, Issue 3 (9-2017)
Abstract

The field of natural hazards research has a rich history in geography, appropriately so because it involves conflicts between physical processes and human systems. Natural events occur without direct human effect and endanger his social life. Events that enforce average annual up to 150000 human damages and more than 140 milliard dollars financial damages on counties and especially developing countries. Among all the natural disasters, the earthquake is one of the most serious ones. It brings tremendous economic losses and deaths of people, as well as the enormous effects on the harmonious and continuous development of society. Iran is an event ism country in the world. In this field look at the recent decades earthquakes statistics that reveal average once in every five years.
Gilan province is located in south western of Caspian Sea in mountainous area of Talesh and central Alborz range that endure many earthquakes up today. The most ancient earthquake ever occurred in this area refers to Marlik civilization which is located near Rudbar – Rostam Abad. One of the recent earthquake in the 20th century in this area is Rudbar earthquake in 21 Jun 1990 with magnitude Ms = 7.7 Richter that caused many destruction. In one hand according to complex tectonic of central Alborz and in the other hand locating Gilan in the south west of Caspian sea that demonstrate many seismic activities, it illustrates as a result that this area is one of the active high potential seismic area of Iran.
The current study is aimed at investigating the earthquake vulnerability of rural and urban settlements of Gilan province. To this end, Euclidean distant analysis and raster overlay have been conducted in GIS. To run the procedure, the first step is to calculate distance (pixels in 86 m dimension) between province and active and inactive fault line based on Euclidean analysis distance in Arc Map. The next step is aimed at standardizing the calculated distances using Raster Calculator Command. The, zoning of earthquake vulnerability of Gilan into five zones (based on active/inactive faults) is the primary goal. As a matter of fact, standardization leads to fuzzy maps. Standard score (distance) is calculated by dividing each score by sum of the scores. The next step tries to categorize zoning map and to translate Raster map into vector one in order to calculate the area of each risk category. Finally, overlay of urban and rural layers base on zoning map may help us analyze seismic hazard urban and rural regions of Gilan province.
Results have shown that 40.72 % of total area of Gilan province are in 15 km distance from active fault. Also, 21.51 % of total area of Gilan province are in 15 to 30 km distance from active fault. Additionally, 64.45 % of total area of Gilan province are in less than 8 km distance from inactive fault (Table 1).
 
Table 1. Seismic hazard zonation according to faults
Probability of earthquake hazard Distance to fault lines Relative area
Active Faults Passive Faults Active Faults Passive Faults
Very low risk 0-20 60-76 32-42 7.29 1.42
Low risk 20-40 45-60 24-32 13.82 3.96
Medium risk 40-60 30-45 16-24 16.66 8.13
High risk 60-80 15-30 8-16 21.51 22.04
Very high risk 80-100 0-15 0-8 40.72 64.45
sum - 100
 
According to seismic hazards due to active faults, 18 cities out of 51 urban regions are severely vulnerable to earthquake. Accordingly, 67.20 % of Gilan urban population are located at high-risk zone. Seismic hazard zoning map based on active faults have indicated that 20 cities are highly vulnerable to earthquake. (Table 2)
 
Table 2. Investigating the risk of earthquake in urban areas of Guilan province
Probability of earthquake hazard urban Settlement Population (2011) Relative population frequency (percent)
Active Faults Passive Faults Active Faults Passive Faults Active Faults Passive Faults
Very low risk 0-20 3 1 135846 17106 1.14 9.07
Low risk 20-40 6 4 86133 144021 9.62 5.75
Medium risk 40-60 10 8 739095 754968 50.43 49.37
High risk 60-80 14 18 380908 273137 18.24 25.44
Very high risk 80-100 18 20 155188 307938 20.57 10.37
sum 51 1497170 100
 
Seismic studies on rural settlement of Gilan province have indicated that 1350 rural out of 2925 rural residences are severely vulnerable to earthquake because they are near to active faults. These regions are the habitat of 24.9 % of the total rural population. Zoning map based on inactive faults have shown that 1679 rural regions are vulnerable to earthquake (Table 3).
 
Table 3. Probability of earthquake hazard in rural settlements
Probability of earthquake hazard Rural Settlement Population (2011) Relative population frequency (percent)
Active Faults Passive Faults Active Faults Passive Faults Active Faults Passive Faults
Very low risk 0-20 162 42 54240 30236 5.51 3.07
Low risk 20-40 379 147 183718 92018 18.68 9.35
Medium risk 40-60 481 291 255412 176183 25.96 17.91
High risk 60-80 553 766 245392 340448 24.95 34.61
Very high risk 80-100 1350 1679 244942 344819 24.90 35.05
sum 2925 983704 100
 
Studies have claimed that the majority of rural and urban regions of Gilan province are severely earthquake-prone. It is due to geographic and natural features of the mentioned province. To this end, some recommendations are given:
  1. Meticulous supervision on safety of building from the stage of plan-making to administration which have to be based on engineering principles for earthquake-prone cities including Baresar, Ataqur, Asalem, Haviq, and Roodbar which are next to active faults
  2. Prevention of formation of suburbs and towns on southern and northern parts of Gilan because these parts are really vulnerable to earthquake
  3. Prediction of temporary accommodation in central Gilan because this part is less vulnerable to earthquake
  4. To equip buildings, hospitals, schools, and other buildings located in big cities including Rasht, Bandar-E Anzali, Fuman, and Lahijan with facilities required in case of earthquake
  5. To hold training courses in rural and urban parts of the mentioned province to make residents prepared for earthquake and for emergency evacuation
  6. To prioritize reformation of old and historical buildings in Rasht because Rasht is mostly laden with old buildings which are really vulnerable to earthquake

Farzaneh Sasanpour, Navid Ahangari, Sadegh Hajinejad,
Volume 4, Issue 3 (9-2017)
Abstract

International studies show that the damages caused by natural hazards is essential that special attention to natural hazards in urban societies of the world, especially in urban areas of developing countries. In many of these communities needed new ways to deal with these challenges. This method should provide sufficient knowledge to identify the nature of problems and the identification of individual characteristics, socio-economic, physical, environmental and management, would in effect do the "Back to Balance" against natural hazards. This feature Back to Balance the same resiliency. The term resilience has a very long history and its use goes back at least a century BC. According to the different interpretations of the concept of resilience, this term is rooted in the traditions of various disciplines such as law, engineering, ecological and social sciences. Today, the concept of resilience has entered the field of planning with different orientations (social, economic, physical, and administrative, etc.).Although it still focuses more attention on environmental issues and a large part of its exploration dedicated to managing the environmental hazards such as earthquakes, floods, hurricanes and global warming. Tehran, as a result of political and economic influence, special conditions to deal with the crisis in terms of the influence of natural disasters and crisis management in terms of organizational structure and legal. In this respect, residential and urban areas of 12 with characteristic their history can be acute against the imbalances caused by natural hazards and create a crisis in urban life. Therefore, the present study has been prepared for the purpose of stability analysis flexibility in District 12 of Tehran metropolitan city.
This is of cognitive research that has been done for analytical and descriptive. All data is obtained in the manner of library and field. The library of available resources and work conducted the form of a questionnaire survey. Questionnaires have been used of type Likert spectrum (numerous, high, high, somewhat, relatively low, low and very low), and its completion is done by fieldwork. Statistical population has problems of urban planning experts, among them 80 people were interviewed for targeted samples. Resiliency that includes four dimensions (economic, social, ecological, environmental and institutional). Was approved the validity of the index by 7 experts manage urban planning problems. For measuring reliability coefficient is calculated Cronbach's alpha equal to 0/79. For data analysis, the use of statistical analysis such as frequency, maximum and minimum, average and standard deviations, T-Test one sample test and Friedman nonparametric test
The results of the indicators of urban resiliency against natural hazards suggests that economic indicators 73/24 Average been determined and relatively low level, ie below the average level. Results of the test showed one sample T-Test is an indicator of economic status of urban resilience against natural hazards of poor utility. As well as the social, ecological, environmental and institutional (organizational) urban resilience against natural hazards associated with poor utility. Finally the 12 metropolitan Tehran metropolitan areautility resilience against natural hazards with respect to all dimensions were too weak. Friedman test results on the scoreboard indicators showed that the index of environmental sustainability (20/33) related to the ecology and environment in the first rank the importance of urban resilience and adaptability Index System (10/11) related to next institutional (organizational) is set as the least significant indicator. Also, significant chi-square statistic is calculated at a rate of 09/67 in three degrees of freedom at the level of 0.000. So, with a probability of 99% can be said that there is a significant difference between the performance rating of 80 specialist urban resilience dimensions (economic, social, ecological, environmental and organizational) against natural hazards, and not the distribution of the same rank.
This research been prepared with the aim of assessing the scale of urban resilience against natural hazards in District 12 of Tehran Metropolis. Results showed that social, environmental and institutional ecology and urban resilience against natural hazards associated with poor desirability. According to this result, it is concluded that the region as a whole is resilient against natural hazards. In this direction, the resilience approach guidance to managers and practitioners use of flexible decisions and concerted policy for urban management. Build resilience in this area to support programmes should invest in organizing access to both external and existing resources in a fair manner, with a coordinated governance structure, and to facilitate social solidarity and support as part of disaster response. The findings also stress the importance of taking an ecological approach to studying resilience to disasters. Many factors from individual, community, and societal levels seem to be important in shaping resilience perceptions of natural hazards survivors. Understanding this evidence will help to validate and further develop indicators of resilience. Our findings point out that, despite existing pre-disaster vulnerabilities, resilience can be fostered following disasters if community members perceive availability of aid and support and mobilize resources Hence, psychosocial support programmes should invest in organizing access to both external and existing resources in a fair manner, with a coordinated governance structure, and to facilitate social solidarity and support as part of disaster response. The findings also stress the importance of taking an ecological approach to studying resilience to disasters. Many factors from individual, community, and societal levels seem to be important in shaping resilience perceptions of natural hazards survivors. Future research should conduct multiple levels of analysis with an all-hazards perspective to reveal how they can be integrated to increase adaptive capacities. Future research should focus on the process of capacity building through informing action to better prepare for disasters. Finally, this research tells us that due to the resiliency of the city will be able to have knowledge of all relevant indicators in the resiliency and reduce the adverse effects of these risks in urban communities

Saeid Hamzeh, Zahra Farahani, Shahriar Mahdavi, Omid Chatrobgoun, Mehdi Gholamnia,
Volume 4, Issue 3 (9-2017)
Abstract

As a result of climate change and reduction in rainfall during the last decade, drought has become big problem in the world, especially in arid and semi-arid areas such as Iran. Therefore drought monitoring and management is great of important. In contrast with the traditional methods which are based on the ground stations measurements and meteorological drought monitoring, using the remote sensing techniques and satellite imagery have become a useful tool for spatio-temporal monitoring of agricultural drought. But using of this technique and its results still need to be evaluated and calibrated for different areas.
The aim of this survey is to study the spatial and temporal patterns of drought using remote sensing and the regional meteorological data in the Markazi province. For this purpose, the MODIS satellite data between the years of 2000-2013 have been used to monitor and derived vegetation indices. Drought indices based on satellite data including the Normalized Difference Vegetation Index (NDVI), Vegetation Condition Index (VCI), Temperature Condition Index (TCI), Temperature Vegetation Dryness Index (TVDI), and Soil Water Index (SWI) were obtained from the MODIS satellite data for the period of study for different temporal scales (seasonal, biannual and annul).Then, correlation between obtained results from satellite data and standardized precipitation index (SPI) have been analyzed in all time periods.
Results show that study area has a low to medium vegetation cover. According to the results, the climate situation of the study area is more compatible with the seasonal results of the VCI, and VCI was selected as the best indicator for agricultural drought monitoring in the study are. The obtained results from the applying of VCI over the area show the drought condition in 2000 and 2008 and the wetness in 2009 and 2010 during the study period.

Dr Parvin Zarei, Dr Ali Talebi, Dr Mahmoud Alaei Taleghani,
Volume 4, Issue 4 (1-2018)
Abstract

Landslides are considered as natural disasters that lead to many deaths and severe property damages worldwide. Therefore, it is necessary to investigate the effective factors in order to make urgent planning and to present management solutions for the sensitive regions. Massive movement of materials, such as a landslide, is one of the problematic hillslope processes in Javanrood located in the northwest of folded Zagros, for this phenomenon leads to demolition of forest lands, farms, and pastures of the region. Moreover, it is considered as a threat for road traffic. The present study aims slope stability analyses and landslide hazard zonation applying the process-based model (Sinmap).
This research was done by both field and experimental methods. Research steps are summarized as following.
Geomorphologic, hydrologic and soil mechanic characteristics of slopes in the considered zone were the required information in this study. To obtain this information, at first, it was necessary to recognize sample slopes to measure the above- mentioned variables. Therefore, first of all, landslides distribution map was prepared in the considered area then, on this basin, sample slopes were selected to measure essential variables. Sample hillslopes were recognized as 12 hillslopes, 5 stable (lack of land sliding) and 7 unstable hillslopes (having land sliding mass). They were 1- 12 numbers. 1-5 hillslopes are stable and 6-12 unstable. After selecting sample hillslopes, necessary parameters were assessed as following:
Mechanical features of soil: soil sampling from each hillslope was done the mechanical features of soil, so 50 kg soil was removed from each slope, from 75 cm to 1cm depth. In order to sampling soft and coarse soils, a core cuter devise and shovel were used, respectively. Sampled soils were transferred to Kermanshah soil mechanic laboratory, Kermanshah provincial transport office and necessary parameters, including dry soil specific weight(γ d), wet soil specific weight (γt), hydraulic conductivity , soil internal friction angle(φ) ,soil cohesion , and soil porosity were determined by using direct shear test.
Determining the geometric parameters of slopes: except for using topography map, altitude numerical model (Dem) with a pixel size of 20 by 20 m and satellite images were used to determine morphology parameters and to identify various hillslope types. Applying GIS software, manual and laser tape measure, clinometer, slope geometry characteristics such as mean slope (beta), slope width (W), slope length (L) area, were extracted.
Model implementation
The model used in this study was Talebi (2008) model which was, in fact, an extended model of process-oriented (physically based) model, being a combination of geometry model, hydrology model (permanent condition) and infinite slope stability theory. After obtaining necessary parameters to get slope factor of security (F S) including laboratory, topography and hydrology parameters, Fs values for each slope were measured by Matlab software
Unstable slopes of the region mainly have the stability coefficient less than 1 which is classified as very high vulnerable class. They have low inner friction angle, less than 29 degrees, based on geo-mechanic properties of soil. Moreover, their gradient angle is more than 35 percent. In term of shape, most of them have concave profile curvature and convergent plan which lead to slower drainage, the increase of relative saturation saving of the soil, and the decrease of stability. The results of the landslide hazard zonation mapping indicate that the majority of the study area located in protection class includes 26 percent of the study area. The lowest percentage of study area belonging to middle stability and quasi-stable classes which constitute 9.2 and 6.2 precent of the study area respectively.
According to landslide hazard zonation applying the process-based model (Sinmap), it can be included that percentage of stability is less than percentage of instability in Javarood region. So that the highest percentage of area is located in the protective class (26 %) and high threshold of instability (15.9 %) and a lower percentage of the region is located as stable and quasi-stable (20 %).This results indicates  that the susceptibility of the scope of the study area in terms of inherent instability. So that natural factors (concave longitudinal profile and low friction, high angle of slope and high saturation coefficient) in these areas will certainly cause the landslide phenomenon. Therefore, this hillslopes will unstable under the influence of human activities such as leveling hillslope for the construction of residential or their road cutting.

Marzieh Taabe, Abolfazl Ranjbarfordoei, Sayed Hojat Mousavi, Mohammad Khosroshahi,
Volume 4, Issue 4 (1-2018)
Abstract

The correct management in natural ecosystems is not possible without knowledge of the health in its sectors. Vegetation is the most significant sector in ecosystem that has important role in its health. Resilience is one of the defining features of health vegetation The term resilience was first introduced in the study of ecological systems and demonstrates the ability of the ecosystem to maintain its performance in the face of environmental disorders. A resilience-based system is not only equipped with a disorder adjustment mechanism but also has the potential to benefit from changes in a way that lead to creating an opportunity for development, innovation, and updating. Therefore, when a change occurs, the resilience provides the needed conditions for restarting and reorganization. If this goes beyond disturbing forces, the system will have the power to return to the maximum vegetation density with the least erosion effects, otherwise the system will be vulnerable to the change that was created and could already be controlled.
This research was done in part of North east of South Khorasan province (arid climate) with the aim of quantifying vegetative resilience on behalf of ecosystem health in response to drought occurrences and long-term precipitation changes, as environmental disturbances. Therefore first, using daily precipitation data from 15 meteorological stations around the study area, their annual precipitation was extracted and was standardized by Standard Precipitation Index (SPI) over the course of thirty years (1986 - 2015). Then, the SPI index data in 15 stations were interpolated by ArcGIS software based on Inverse Distance Weighted (IDW) method and dry, wet and normal years was estimated in the study region for each year. On the other hand, from archive of satellite images of Landsat 5 and Landsat 7, an image was created for each year in study period, between 15 June and 15 July, with permanent coverage at the best of growth. Following the necessary corrections for satellite images, the average Transformed Normalized Difference Vegetation Index (TNDVI) was obtained of each image by ENVI software. Finally, effected of precipitation changes on mean TNDVI was assessed and vegetation resilience was stabilized whit selected of sever time period samples based on four effective parameters (Amplitude, Malleability, Damping and Hysteresis).

Comparison of annual precipitation variations in the thirty-year time series (1986 -2015) indicated two approximate wet and dry periods in study area. The wet period is related to the first fourteen years of the time series (1986-1999) and the dry period is related to the last sixteen years (2000-2015). In this term, severe precipitation incidents with different intensities were occurred in the study area including one case of very intense precipitation (1986), one case of intense precipitation (1991) and two cases of moderate precipitation (1996 and 1992). Also, four drought incidents were occurred including one case of intense drought (2001) and three cases of moderate drought (1987, 2006 and 2008). All precipitations (wet years) are related to the first half and most droughts are related to the second half of the studied period. In this study for fixing of vegetation resilience in study area and for calculating of its parameters, In addition to the thirty-year time series selected sever time sections. in the whole study series (1986 - 2015), maximum of mean TNDVI (49.37 %) was in 1986 (reference), the lowest mean TNDVI (43.58%) was in 2010, The year effect of the decrease precipitation and drought, and mean TNDVI in 2015 was 44.28 %. Amount of parameters amplitude, malleability and damping are respectively 5.79, 0.7 and 5.09, and hysteresis was zero (%). The result of this case showed that the vegetation has moved towards the reference state (Resilience) but has not reached to amount of reference vegetation. The most specific cases for vegetation resilience happened from 1986 to 1996 (wet period) and 2003- 2009 time sector (dry period). In the first time section amount of amplitude and malleability were 0.64 %, damping was zero and hysteresis was 0.25%. The result of this case showed that not only the vegetation was returned to the reference state but also was increased to the reference (Cross reference).So despite the reduced rainfall and occurrence of sever occurrences of drought in dry period, hysteresis parameter (0.05 %) observed in 2003- 2009 time sector too that confirmed clearly vegetation health in study area whit dry climate. 


Awareness of the health status of the vegetation and its response to long-term precipitation changes and environmental disorders, such as drought occurrence, ensure the success of the managerial plans for renewable natural resources. The present study is the second study on quantifying the vegetation resilience and the first study under dry climatic conditions in Asia (an average annual precipitation of 160 mm) conducted in Iran by calculating four factors related to resilience, and is the first study that has presented the factor hysteresis in the calculations. Despite continuous of difficult condition, the native vegetation of the study area has been able to return the reference state not only by resolving the disorder relatively, but also it has experienced hysteresis stage. A set of quantitative calculations showed despite reduced annual precipitation and drought events, vegetation has been able to maintain its resilience, which indicates the health of the vegetation in the studied ecosystem. With the presence of such amazing protective and consistent mechanisms in the vegetation of arid regions, it is possible to maintain and restore these regions by proper managerial plans.

 


Dr. Firouz Mojarrad, Mrs. Samira Koshki, Dr. Jafar Masompour, Dr. Morteza Miri,
Volume 4, Issue 4 (1-2018)
Abstract

Thunderstorm is a destructive atmospheric phenomenon, which annually causes a lot of damage to various parts of human activities. Due to the accompaniment of thunderstorm with rainstorm and hail and its effective role in creating sudden floods, the analysis of the behavior of this hazard has been widely studied both in terms of agriculture and in terms of financial and life damages throughout the world. The study of thunderstorm as a hazardous atmospheric phenomenon using instability indexes in Iran has been less considered due to lack of observation stations. Convective Available Potential Energy (CAPE) and Vertical Wind Shear (VWS) are two indexes that are often used to describe and detect thunderstorm environments. This study evaluates the thunderstorms in Iran with reanalysis data using CAPE and VWS indexes.
Thunderstorm data in 7 different conditions at 8 times a day for 42 synoptic and upper air stations during a 37-year common period (1980-2016) was received from the Iranian Meteorological Organization. At first, frequency, trend and time of occurrence of thunderstorms in Iran were investigated during the statistical period. Then, the ERA-Interim reanalysis dataset of the European Centre for Medium-Range Weather Forecasts (ECMWF) with spatial resolution of 0.5 ° was used for the analysis of thunderstorms. To evaluate the ERA-Interim dataset, the CAPE and VWS values for the 80 selected thunderstorm events that were calculated using the RAOB software were compared with ERA data and their accuracy was confirmed. After confirming the accuracy of ERA data, the average values of CAPE and VWS indexes in 42 stations of the country were calculated based on 4,542 thunderstorm events at 00 and 12 GMT during the study period, and the maps of these two indexes were drawn up using the IDW method. Then, using an equation, the thunderstorm severity thresholds across the country were determined using ERA data with 4,542 thunderstorm events to distinguish between mild, severe and very severe storms. To ensure the selection of important storms, storms with CAPE values of less than 50 were removed to exclude poor environments for convection occurrence. As a result, out of 4,542 thunderstorms, 535 events were eliminated and 4007 events remained. On this basis, a "2 x 2 contingency table" was prepared that compares thunderstorm events and forecasts. This table provides the information required to compute warning performance statistics including POD (Probability of Detection), FAR (False Alarm Ratio) and CSI (Critical Success Index). But the results of these statistics did not match well with the conditions of thunderstorm events in Iran. Therefore, the discriminant analysis was used to differentiate the intensity of thunderstorms and to discriminate mild, severe and extremely severe thunderstorms.
The results of the study showed that thunderstorms in Iran are increasing during the statistical period with a regression slope of 0.23 events per year (8.5 events in the statistical period). The highest frequency of thunderstorms was observed in the month of May with an annual number of 111, and the lowest was observed in January with 12 events. Most thunderstorms occur around 21:30. The highest average frequency of annual events at stations was related to the stations of Urmia, Tabriz, Khorramabad and Bushehr respectively. The proper capability of ERA data to estimate instability indexes in Iran was proved. ERA data provides a very near estimate for VWS, but estimates for the CAPE index are slightly more than observational values. The highest values of the CAPE index are observed in southern provinces, as well as in the southwest of the Caspian Sea coasts, and the highest values of the VWS index are found on the Persian Gulf coasts. When the storm severity breakdown equation for the 400 selected storm events was obtained and the "2 x 2 contingency table" was prepared, it was found that this equation was not satisfactory with respect to the POD, FAR, and CSI indexes. Hence, using the discriminant analysis, the storm severity breakdown relationships and their discriminant equations were obtained. These equations categorized 60% of the surveyed thunderstorms correctly. There is no significant difference between the mean values of CAPE and VWS in the three storm intensity groups. The role of the VWS index was higher in determining the type of storm.

Yousef Ghavidel, , ,
Volume 5, Issue 1 (6-2018)
Abstract

Climatic geography of Tropical Cyclone hazards Affective on the southern coasts of Iran
The occurrence of any climatic fringes, including annual tropical storms, leave irreparable risks in its dominated areas. Understanding these events and knowledge of the time of their occurrence can be helpful in managing the unexpected incidents caused by them. Tropical cyclones are important natural turbulent processes in tropical and middle ecosystems in a number of regions of the world. Among the dynamic conditions of the atmosphere for the formation of tropical storms, there are three basic conditions: 1. The vertical wind shear should be limited between the 850 to 200 mb and the wind speed between these levels should be less than 10 meters per second. Such a situation allows the formation of a straight column, without breaking, to initiate tropical storms. 2- The formation state of tropical storms should be such that at least it is five degrees of latitude distant from the equator. Such conditions provide the minimum of Coriolis force to provide the tropical cyclic rotation along with other fundamental and apparent forces of the atmosphere and they occur following the pressure forces, Coriolis and centrifugal forces, cyclostrophic winds, and cyclic circulation in the center of the low pressure. 3- The presence of turbulence or discordance with vorticity and the convergence in the lower troposphere, or the anticyclone rotation and divergence in the upper levels of the atmosphere before the onset of activity, and the formation of tidal disturbances. Tropical storms are created by the presence of various dynamic and thermodynamic factors such as sea surface temperature and moisture content (thermodynamic properties), and flow and vertical winding functions (dynamic characteristics).
The parameters studied in this study for the dynamic and thermodynamic analysis of the tropical rotation of 1948 generally included the mean sea level pressure, geopotential heights, zonal and meridional components of wind, convection available potential energy, convective stabilization index, vertical velocity, relative vorticity, Sea surface temperature, humidity, and cloud cover levels which are drawn from the European Center for Medium Forecast Scale (ECMWF) with spatial resolution of 0.75 applying GRADS software. The study of combinational maps of 500 milligrams of geopotential heights and vorticity advection on the first day of the cyclone (1948/06/05) indicates the presence of a very strong low-altitude center with seven closed curves on the Arabian Sea. The most inner curve of this low-altitude center has the lowest elevation with 5650 geopotential meters height and the maximum vorticity advection and downright negative velocity of 10 and 0.5 Pascal to seconds, respectively. The above-mentioned Jetstream map with a maximum speed of 16 m / s, which covers the east of the center of the altitude, contributes to the greater divergence of this system. The formation of a very strong negative eddy in the 500-mb equilibrium also indicates intense instability at the site of the tropical cyclone and is actually a factor in the formation and reinforcement of such cyclones .The above-mentioned low altitude continues its cyclonic rotation at the level of 850 mb with two closed curves, and the maximum vorticity advection and downright negative velocity of 16 and 0.6 Pascal to second, respectively, due to the presence of lower level radar with a maximum speed of 20 m / s on the south side and similarly, in the south-east, it continued to circulate more rapidly at a rate higher than 500 mb, which results in the formation of the first pressure packet with a central
pressure of 997.5 mb on the sea surface. The high amount of specific humidity of 850 mb from the start of cyclone activity (12 g / kg), and the increase in this parameter in the next days of activity reaches 14 g / kg and also 4.5 g / kg at 500 millimeter equilibrium point to the high humidity at the location of the low-pressure center and the optimum conditions for the extraction of heavy rainfall in the eye wall of cyclone. Cloud cover maps also indicate a climber air density of up to 500 mb and the formation of a cloud at different levels of the atmosphere at the site of the formation of tropical rotation. The results show that the formation of the lower Jetstream, along with the tropical cyclone event (from 05 to 08 of 1948) affecting the southern coast of Iran, has been able to create severe air mass divergences in the left half of the nucleus and following this mechanism and the relationship between this velocity nucleus and the lower levels of the atmosphere and the sea level in the vertical direction, with the convergence of the mass, has been accompanied with the reduction of density and, finally, the reduction of pressure and the formation of turbulence, as the first ring for the development of tropical cyclones; therefore, the altitude of 850 mb and jet stream located at this elevation affected by the high-rise phenomenon on the western shores of the ocean (sometimes in the east of Madagascar) is considered as one of the most effective dynamic factors for the birth and development of this tropical cyclone on the southern coast of Iran. The tropical cyclone was formed from June 5 to June 8, 1948, at approximately 16 degrees north and 60 degrees east on the Arabian Sea. And, in general, the interaction between high pressure tongues on Saudi Arabia, Tibet and Iran, and the tropical cyclones has prepared the conditions for the activity and displacement of the tropical rotation. Previous studies of tropical storms have considered other synthetic systems, such as cyclones over Europe, and the integration of cyclones on the Mediterranean and Oman, as well as the displacement of the axis of tropical cyclones at middle and upper levels of the atmosphere affective in the escalation and displacement of the storm. It is also believed that the southern coast of Iran is also effective, and in general, less attention is paid to the causes of the development of the storm.
Key words:Tropical Cyclone, dynamic and thermodynamic analysis, low level jet stream, Thermodynamic parameters, Southern coast of Iran

Faryad Shayesteh, , ,
Volume 5, Issue 1 (6-2018)
Abstract

The role of tropospheric vertical anomalies in rainfall solid Case study: the hazard of hail in Kermanshah
Climate risks is one of the Types of hazards that damages human communities such as the phenomenon of hail, in the micro-scale, it causes financial losses and casualties. Hail is associated to the atmospheric elements and geo-location factors. Whenever weather conditions and appropriate physical processes are combined with geo-location creates and intensifies this phenomenon.
Losses resulted from hail has been more effective in the agricultural sector and in the effect of damaging the crops When growth and budding. However, it disorders in other sectors such as, blemishing residential buildings, Losing large and small animals also, damaging to the aircraft flight and its components. Hail considerable damage in Kermanshah province every year so that Farmers insure their crops against this Phenomenon and the government will incur heavy costs for
damage that is inflicted on the sector of activity.
Research methodology
The current weather data has been used with 3-hour intervals in the statistical period of 65 years (1951 to 2016) from synoptic stations of Kermanshah Province that includes the stations of Kermanshah, West Islamabad, Ravansar, Kangavar, West Gilan, and Sar-e-Pole-Zahab.
Among the 100 present weather code, Codes 99, 96, 91, 90, 89, 87 and 27 have been considered that including hail phenomenon by varying intensities and includes any appearance of this phenomenon in Hours scout and three hours earlier. Then, based on the above code, Were coded in Excel to identifies Codes 96, 91, 90, 89, 87 and 27 When entering from the Meteorological Data To the desired program among Group VII of the data, And when the written code, were identified, Hail days were marked.
Given that in this study Hail is studied regarding the synoptic conditions and temperature anomalies. Therefore, for the synoptic situation, Pressure data, vorticity, Special moisture, Components U and V, Omega transverse profile And outgoing longwave radiation, And for the temperature anomaly, Temperature and isothermal anomalies components Were getting from esrl.noaa.gov/psd site And using the software Grads were drawn maps for a selected day To determine the formation of hail.
Commentaries Results
The frequency of occurrence of hail has reached 187 in the period 65 years in Kermanshah province. This phenomenon generally occurs from mid-September to mid-June. The most number has been in Kermanshah station and the Least in Sar-Pol-Zahab station.
April has had the highest number of hail frequencies in Kermanshah province and the greatest losses in the month related to the agricultural sector. Therefore, Select System hail seems essential to examine how the temperature anomalies and the formation of hail in the month.
On the day of the event, trough hail has been formed in the East Mediterranean.Wrying the trough axis From North East to South West resulted in cold air from high latitudes to the East of the Mediterranean.
The establishment of trough in the middle and low pressure level in sea level and its following Convergence in the balance has created positive omega until balance of 200 hPa and most serious it is at the level of 400 hPa. Negative omega has maintained its association from ground surface until High levels in the study area.
The airflow of vorticity balance 1000 and 500 Hpa Suggests vorticity positive settlement area on the case study. Establishment of short wave in the vicinity of the study area and intensifying ascending conditions also Prolong Positive trough conditions from surface of Earth until 500hpa balance have been The necessary dynamic conditions for Hail in this day.
Special moisture and wind Vector with 700hpa balance of Moisture transfer has been done by two opposite vorticity system. Trough rotary motion Based on the Mediterranean and along the Red Sea on the one hand and Moving anticyclone over the Arabian Sea And the Persian Gulf and Oman Sea on the other, have conveyed Moisture of all moisture sources from The seas around to The study area.
Also OLR anomalies for the hail event day indicates being Negative in the study area and the sharp decline of Outgoing longwave in this day Compared to its long-term average And hence the conditions of cloudiness and the formation and intensification of convection has been provided.
1000 hpa positive anomaly 2 ° is representative the Higher than the average temperature conditions and in the 500hpa anomaly balance Minus 2 degrees Celsius is representative Lower than normal temperatures in the balance. These factors aggravate the vertical temperature gradient in the study area these days. 20+ degrees Celsius the Isothermal curve and -20 ° C. Respectively, the levels of 1000 and 500 Drawn to the area of study And has created a large temperature difference Between the upper and lower levels.
Keywords: Synoptic analysis, Hail hazard, Tropospheric anomalies, Vorticity, Kermanshah Province

Amir Saffari, Amir Saffari, Jalal Karami,
Volume 5, Issue 1 (6-2018)
Abstract

Investigation about the influence of land-cover and land use changes on soil erodibility potential, case study: Gharesou, Gorganrood
Land use and land cover (LUC) change associated with climatic and geomorphologic conditions of the area have an accelerating impact on the land degradation. Natural as well as human-induced land use land cover change (LUCC) has significant impacts on regional soil degradation, including soil erosion, soil acidification, nutrient leaching, and organic matter depletion. Since the last century, soil erosion accelerated by human activities has become a serious environmental problem. It has a manifold environmental impact by negatively affecting water supply, reservoir storage capacity, agricultural productivity, and freshwater ecology of the region. In recent years, many researchers have highlighted the environmental consequences of soil erosion.
Soil erosion estimation at a regional scale is influenced by the complexity of the soil erosion process and the availability of data describing the soil erosion factors. In the last decade, regional and national level assessments of soil erosion were carried out using different approaches, ranging from indicator or factor-based approaches to process-based models. However, the revised universal soil loss (RUSLE) and its modifications are still widely used because of its simplicity and a greater availability of input parameters.
Gharesou basin is one of the sub-basins of Gharesou, it suffered from severe erosion in some areas over the past years. This erosion has occurred for different reasons and one of them is land use change and weak management of water and soil resources. The purpose of this research is to investigate the effects of land-cover changes on the potential of soil erosion in Gharesou Basin, a sub-basin of Gorganrood, in Golestan province. For this, we have employed RUSLE Model and used landsat satellite images from the sensors of TM, ETM, and OLI for 1985, 2000, and 2015. The potential soil erosion in this study was estimated using RUSLE model, which can be described using following equation:
A = R × K × LS × C × P
where A is amount of soil erosion calculated in tons per hectare per year, R is rainfall factor , K is soil erodibility factor , L is slope length factor, S is slope steepness factor, C is cover and management factor, and P is erosion control practice factor. To run the RUSLE model in GIS, first, rainfall raster layer, soil, slope, Digital Elevation Model, and also layers of soil protection range were created. Each of the involved factors was calculated in separate units in the basin level. In this research, Gharesou basin was analyzed based on raster network data with 30 meters cell size, because, from one hand it's small
enough to show heterogeneity of the basin and on the other hand, it matches pixel dimensions of landsat satellite images.
The results of land-cover changes have revealed a decrease in dense forest areas, low forest areas and the mixture of orchard, forest and pastures in a thirty years period. According to the results of RUSLE, changes of the classes indicate a general trend to the soil loss in the basin. Therefore, Gharesou basin is a basin with increasing soil erosion potential. In the plain and coastal plain areas of the basin, that is the mainly cultivated area, the amount of erosion is different from the other areas, and soil loss process is decreasing. It's due to the changes of cultivation method from traditional to modern, increase of irrigated farming area, choosing more environmentally friendly plants, and also, increase in the area of cities and villages from 7.14 percent to 29.04 percent during 30 years. In the study classes, for output of RUSLE model, in every 3 years of study, the maximum area relates to the classes of 100 to 200 Ton per year that is more seen in the mountainous regions. In these regions, all factors except vegetation are toward soil loss. Also, during 30 years, the amount of dense vegetation decreased from 34.56 to 31.55. In fact the only factor in protecting soil in (prone to erosion) areas has given its place to less effective vegetation, so, the area of this region has increased and Gharesou basin is in danger of soil loss in mountainous and forest parts. Also, areas with more than 200 Ton in hectare, with the lowest amount, have had a tangible increase during 30 year of study and its amount has increased from 11.74 to 12.50. These areas are usually located in mountainous parts with no vegetation. Also, the average of soil erosion potential estimated in Gharesou basin for 1985, 2000 and 2015 is 102.02, 103.11, and 103.76 (ton per hectare per year). This amount was found in the sub-basins too and except the sub-basin 4 located in coastal plain areas of the basin, with farming use, the amount of other sub-basins is increasing. According to the results of study, mountainous parts of Gharesou basin, has the most damage due to the accumulation of involved factors in the potential increase of soil loss. So, the necessity of watershed management is observed. Also modification of cultivation pattern and soil conservation training in farming lands of foothills and hillsides are required.
Keywords: RUSLE Model, soil erosion, Gharesou, Remote Sensing, land-cover changes

Aliakbar Anabestani, Mahdi Javanshiri, Hamideh Mahmoudi, Mohammad-Reza Darban Astaneh,
Volume 5, Issue 1 (6-2018)
Abstract

Spatial Analysis of Villagers’ Resilience Against Environmental Hazards
(A Case Study of Central District of Faruj County)
Statement of the problem
The concept of resilience is the outcome of changes in risk managing in current decade. Today, the views and theories of disaster management and sustainable development seek to create societies resilient against natural disasters. Natural disasters such as earthquakes, droughts, floods, etc. are inevitable phenomenon which always pose a serious threat to development, especially in rural areas. This reflects the need to pay more attention to resilience in local level (rural areas). Resilience is the ability of a social or ecological system to absorb and deal with disorder or disturbance, so that the basic functional structure, can maintain the capacity of reorganization and adapting to changes and tensions. Carpenter defines resilience as the capacity of an environmental and social system to absorb a disruption, reorganize and thereby maintain essential functions. Thus, in order to reduce damage caused by natural disasters, the capacity of rural areas to deal with these events should be increased. Increased level of resilience against natural hazards is possible through accurately identifying the factors affecting resilience. Therefore, the aim of this study is the spatial analysis of factors affecting the promotion of rural environmental resilience in the face of natural hazards in rural areas of Faruj County.
In fact, the present study seeks to answer the following questions: what are the factors which may increase the level of resilience in the sample communities exposed to natural hazards, and how resilient are the sample villages of the study?
Research Methodology
This study is an applied research conducted in a descriptive-analytical method based on questionnaires. Data were collected through library research and field works which required completing questionnaires and conducting interviews with villagers living in the Central District of Faruj County.
Validity of the questionnaires was confirmed based on experts' views and its reliability was calculated using Cronbach alpha for different dimensions. The population consisted of 4591 households from the villages suitable for temporary accommodation. Based on the Cochran formula, 252 were obtained from these samples. They were selected by stratified random sampling.
Using statistical analysis methods in SPSS software, we analyzed the data to measure resilience in sample villages of the study area. We also used Excel and GIS in various parts of the study. To determine the best option, we used the VIKOR models, Gray relational analysis and Additive Ratio Assessment (ARAS).
Results and discussion
The results showed that infrastructure dimension with a mean of 2.92 and the economic dimension with a mean of 2.58 respectively had the highest and least impact on increased resilience which suggest that these villages compared to sample villages have relatively good infrastructure facilities. However, due
to the lack of proper institutional framework and poor performance of crisis management institutions, villagers are less satisfied with these organizations. Accordingly, based on t-test, the actual mean of the total respondents’ views was less than 3 and at the moderate level, and the economic index with the t statistics of -10.38 had the most negative impact on the resilience of the villagers.
It should be noted that according to the results of the resilience correlation with the individual characteristics of the respondents, it became clear that the gender and marital status has a direct and weak relationship with each dimension of resilience, which means men and the married people compared to the women and the singles believe their villages are more resilient. Besides, there is a weak and reverse relationship between the education of the individuals and their resilience, meaning that people with lower education compared to educated people, believe their villages are more resilient. There was no relationship between age and the dimensions of resilience.
In order to assess the impact of each index of the study on the level of resilience in the villages of the study, the confirmatory factor analysis test was used which revealed that among the indices of the study, "the villagers’ satisfaction with the performance of the Rural Council and administers (Dehyars)", "the role of institutions in educating people about various incidents" and "the use of new and durable materials to prevent the damaging effects of the incidents" had the greatest effect on the resilience of the samples villages.
Eventually, to determine the best village in terms of resilience for establishing a temporary settlement site in crisis management, we use three techniques: additive ratio assessment (ARSA),- VIKOR and Gray relational analysis. We prioritized the villages based on the mean rank method. -Considering the indices of resilience in the rural areas of the study, the villages of Mefrangah, Ostad and Pirali have the highest ranks, and the villages of Rizeh and Roshavanlou have the lowest ranks.
Key words: resilience, environmental hazards, organizational-institutional dimension, additive ratio assessment (ARSA), Faruj Central District

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