Showing 733 results for Type of Study: Research
Engineer Elham Azizikhadem, Doctor Kazem Rangzan, Doctor Mostafa Kabolizade, Engineer Ayob Taghizadeh,
Volume 18, Issue 51 (6-2018)
Abstract
The tourism industry has become a major economic activity in the early years of the 21st Century and is considered one of the most productive and most employment-oriented global industries. Tourism is one of the most important factors generating wealth and employment in the world. It is necessary to plan for the proper exploitation of this industry, The most important steps to plan are to locate sites for providing tourists with the services they need in the form of tourist villages, This research is for the city of Shush which is one of the most important tourist areas of Khuzestan province And since it has many ancient monuments, it has attracted many tourists, , But the city has been at a very low level in terms of having a space worthy of tourists. Therefore, the conditions reinforced the idea of creating a tourism village. In this research, location-based discussion was conducted through a fuzzy inference system, Finally, the Fuzzy Topsis method has been used to protect the environment and to some extent extend sustainable tourism development. The ranking of these sites is based on environmental criteria. In the fuzzy inference system by applying the layers required in this method, four sites are considered to be very suitable.Then, using Fuzzy Topsis, which includes 10 criteria and 4 options, identified the best site on site 4. This site will bring the least damage to the environment, Located on the banks of the Dez River, most of the area has been covered by ground. In terms of maintaining environmental criteria, the site has a completely organic environment than other sites.
Ahmad Pourahmad, Nabi Moradpour, Hossen Hataminejad,
Volume 18, Issue 51 (6-2018)
Abstract
This study examined the effect of physical dimensions - space to encourage walking in Tehran. Micro level and macro level of the position of the subject matter, the authors were forced to Amirabad area of Tehran University as an area of study of their choice. The research method is analytical and survey. And the questionnaire for citizens was used. The population of the study, all residents of the neighborhood Amirabad and up Tehran University, using a sample of 384 randomly selected examples. The writers for more accurate research results, the sample size has been increased to 400. For data analysis software is used SPSS21 and LISREL8. The results indicate that the physical dimensions - space and encourage walking there. The amount of factor loadings obtained in all the research indicates that the selected indicators to measure the physical dimensions of space, encourage walking properly measure these dimensions, so that the physical dimensions, safety index (99/0 ) and the spatial dimensions of the security indicator (75/0) have had the highest amount of loadings. In addition, the effect of spatial scale on a direct and positive are encouraged to walk in space as well as the physical dimensions of 34/0 and 42/0 of variance explained that encourage walking.
Hossein Imani Pour, Abdolreza Kashki, Mokhtar Karami,
Volume 18, Issue 51 (6-2018)
Abstract
Heating requirements are one of the most important human issues in the fields of agriculture, tourism and energy management in the present and future .Knowing the extent of these changes can be very effective in making decision makers. The purpose of this study is to examine the changes in the requirements of the heating degree day in conditions of climate change in southern Khorasan province. For this purpose, daily data from the minimum and maximum temperature of 11 stations of the South Khorasan province were received from the Meteorological Organization of Iran during the period of 1990-2015. The latest available scenarios of the fifth report of the Climate Change Interagency Panel (AR5 2014) include RCP scenarios from the Canadian Climate Change website and, using the SDSM macroeconomic statistics software, the data for the upcoming period (2016-2046) in the study area was thrown off. Using the Matlab software capability, the monthly and annual heating requirements of the stations were calculated in the current and future period. Finally, using the Kriging interpolation method, the zoning maps for cooling requirements for the current and future period are mapped in ArcGIS software. By examining the effect of geographic features (latitude and longitude and station height) on the heating needs in the area, it was determined that the role of heights is very effective in changing the heating needs. In the cold months of the year (Azar, Dey and Bahman), the highlands (Qain, Arsak, Fath Abad, Aryan Shahr, Darmian) require higher energy levels due to the need for higher temperatures. Increasing the temperature and warming of the air in the future, especially in the months of Farvardin and Mehr in most places, requires less use of exhaustible equipment in the future.
Yousef Ghavidel Rahimi, Manouchehr Farajzadeh, Esmaeel Lashani Zand,
Volume 18, Issue 51 (6-2018)
Abstract
In this study, the changes in the Khorramabad storm in the period of 1952 to 2015 have been investigated. For this purpose, data from meteorological codes 06 and 07 were received from the Meteorological Organization of the country, and after identifying the days of winding with dust storms and calculating their monthly frequency, monthly, seasonal and annual time series were analyzed. In this study, descriptive statistics, cluster analysis, linear and polynomial trend analysis, and nonparametric Mann-Kendal test were used to study the frequency variation of dust storms in Khorramabad station. The results of the research showed that the monthly frequency of dust storms in Khorramabad station in the middle of May, July and June is May and July, respectively, and from May to July (May to July), the frequency of storms in the dust and dust Khoramabad station is added that this issue is not related to the district heating and dry season. In the seasonal season other than the autumn, which is not frequent with frequent dust storms, in the rest of the seasons, especially in spring and summer, the seasonal concentration of dust storms in Khoramabad has been intensified. The analysis of the trend of time variation in the occurrence of dust storms in Khorramabad station showed that in most of the months of the year and in the three seasons of spring, summer and autumn, as well as in the annual period, there was a significant change in the frequency of dust storms in Khorramabad station. It is increasing with a relatively steep slope, indicating that in the future, the frequency of dust storms in Khorramabad station will be increased.
Doctor Maryam Ilanloo, Sir Hosein Bicgarian, Sir Mohsen Yahya Soltani, Sir Mohammad Mehdi Bahramian,
Volume 19, Issue 52 (3-2019)
Abstract
Solid waste is an integral part of human life, generation of various quantities and qualities of which is one of the greatest environmental problems of the current era. Application of modern tools and technology to find the right place for recycling, where the volume of recyclable materials can be reduced, seems vital for reusing the recoverable materials contained in normal waste and their recycling and reusing in the cycle of industry. The study aimed to find a location for recycling and its converting industries in Kelardasht, Iran. This was a descriptive and analytical research with a survey approach. At first, experts of the field were recognized and a scientific panel was formed to identify the relevant criteria through Delphi method. In this respect, five criteria of the distance from residential and commercial areas, the distance from urban streets, the distance from the river, the distance from the hospital and education centers, and the distance from hotels, banks, and offices were selected. After that, the permitted distances for these criteria were determined by Delphi technique, followed by the application of the centroid method to determine the exact distances. Moreover, the analytical hierarchy process (AHP) and geographic information system (GIS) were exploited to determine the and use weights in raster maps and generation of the zoning map. Furthermore, the best locations for recycling were selected in Kelardasht using field survey method and based on the zoning map. According to the results, four sites were selected for recycling of recoverable solid waste in this region
Mr Sirous Hashemi Darebadami, Dr Ali Darvishi Boloorani, Dr Seyed Kazem Alavipanah, Mr Mohammad Maleki, Mr Reza Bayat,
Volume 19, Issue 52 (3-2019)
Abstract
The term urban heat island (UHI), described the phenomenon of climate change in urban areas compared with surrounding rural areas. UHI effects include: increasing in energy and water consumption, air pollution expansion and interfering in thermal comfort. Surface urban heat island (SUHI) contains patterns of land surface temperature (LST) in urban areas that has interaction with UHI in urban canopy layer and urban boundary layer and investigate with thermal remote sensing. SUHI has diurnal and seasonal variations so requires multi-temporal data to analysis SUHI. In this study, the multi-temporal MODIS (Aqua and Terra) data product were used to analyze the SUHI in day and night in Tehran metropolitan. Physical and biophysical surface properties such as: land cover/land use (LULC), elevation, albedo, vegetation index (NDVI) and impervious surfaces index (NDBI) were used to interpretation of the LST and SUHI changes. The results showed that SUHI in Tehran, has spatial-temporal diurnal and seasonal variation. So that during warm days the surface urban cool island (SUCL) is formed in Tehran. At night times, SUHI index values was different between 2 and 5 ° C (maximum in the spring). The results also showed that different of land cover thermal properties, albedo and elevation was the most important factors is the diurnal changes of SUHI while phonological changes of vegetation and albedo, was the most important factors in seasonal changes of SUHI.
Dr Vahid Riahi, Dr Parviz Zeaiean Firouzabadi, Dr Farhad Azizpour, Ms Parastoo Darouei,
Volume 19, Issue 52 (3-2019)
Abstract
The cognition of cropping pattern is important for planning and resource management .Remote sensing as a science and technology of spatial information and geographic information system due to having the analytical facilities can play a key role in determining the distribution of crops and their lands under cultivation. In this research, in order to identify and separate the lands under cultivation of the dominant crops in Lenjanat of Isfahan province, the multi-temporal images of Landsat 8 satellite, OLI sensor were used in the dates of April 17, July 6, and August 23 in 2016. Using maximum likelihood classification and normalized difference vegetation index (NDVI) of the agriculture crops in different periods of growth and according to their cropping calendar, the map of the cropping pattern of the area was determined. To evaluate the accuracy of the results, the produced maps were examined with reference data. Kappa coefficient and overall accuracy were 0.88 and 90%, respectively, in maximum likelihood classification, and 0.90 and 93%, respectively, in NDVI. Furthermore, statistics presented by Agricultural Jihad Organization of Isfahan province in the 2015-2016 crop year was used for evaluation. The results showed that there were differences equal to 10.2%, 18.6% and 1.8%, in the area under cultivation of wheat and barley, rice, and potato and forage, respectively, in maximum likelihood classification, comparing with the statistics of Agriculture Jihad while the results of NDVI comparing with Jihad statistics showed the errors equal to 6.6 %, 6.5 % and 3.2%, respectively, that indicated the better performance of temporal vegetation indices in estimation of area under cultivation according to its phenology. Investigation of land use and cropping pattern of this area indicate a high centralization of agricultural lands with high water requirements and industries on the proximity of Zayanderud River which necessitates the spatial analysis of land use in this area.
Sayyed Mohamad Hosseini, Abdolhossein Adelzadeh,
Volume 19, Issue 52 (3-2019)
Abstract
In this research, applied synoptic model for determining the average daily temperature and its relationship with the Geopotential Height in middle level (500 HPa). Therefore, two database were used: database of atmospheric circulations, includes the data of geopotential height at 500 HPa and its data were extracted from the NCEP/DOE(US National Oceanic and Atmospheric Administration) in hours 00:00; 03:00; 06:00; 09:00; 12:00; 15:00; 18:00; and 21:00 in Zulu and other, database of environmental (surface) events. Contain of average daily temperature in the Mashhad, Torbat-Heydarieh and Sabzevar stations in Khorasan Razavi Province. The maximum and minimum of these stations in the time interval from 01/01/1987 to 01/01/2014 equal as 9862 days from the meteorological organization of Iran. Then, was calculated the correlation of the average daily temperature of selected stations with high atmospheric data (500 HPa level) with the northern hemisphere in Surfer Software. The result shown, four regions in the northern hemisphere which had high correlations with selected stations. The correlation results suggest that the United States has 25 pixels, Northern China 25 pixels, Africa 45 pixels and Japan with 65 pixels. Then, weighted average of pixels in heights by multiple regression equation station. The results of diagnostic models indicate that, per geopotential height increase in the profile, the average daily temperatures of selected stations in the Sabzevar 1.4, Torbat-Heydarieh 1.3 and Mashhad 1.3 degrees Celsius will increase.
Najmeh Shafiei, Mohamad Ali Zanganeh Asadi, Javad Jamalabadi, Zeinab Mojarrad Titkanlo,
Volume 19, Issue 52 (3-2019)
Abstract
In evaluating and studying natural phenomena, we sometimes encounter certain seemingly independent forms and processes and phenomena that are related to each other and can be analyzed through a series of mathematical equations and correlations, but sometimes paired phenomena It is found that they have certain relations with each other, but these relationships can not be called correlation, but their relationship has caused them to be presented as a double (a type of conjugacy) and they would appear to be opposing reactions in terms of collocation. The tectonic changes, especially the neonate movements, and its effects and consequences on groundwater reserves of these types of reactions. The purpose of this study is to investigate causes of groundwater drops in the framework of geodetic theory. With regard to the fact that in recent years, the water level in the northern plain of Mangasani has fallen sharply. Undoubtedly, non-structural activities in the region, along with other influential factors (uncontrolled harvesting of groundwater resources, droughts, etc.), can be attributed to The title is one of the main causes of water loss in the region. For this purpose, with the aim of evaluating the tectonic activity of the area, some geomorphic indices such as basin shape index (BS), drainage asymmetry index (AF), inverse topographic symmetry (T), mountain front sinus index (J), hypersonic integral (Hi), Valley Depth Wide Index (VF), River Sinusity Index (S), Longitudinal River Gradient (SL), Relative Tactical Rating Index (Iat), and Hierarchical Anomalies Index (Δa) have been used. The results show that the whole basin is dynamic in terms of tectonic activity. The tectonic situation in the range and the results of statistical data indicate a change in the level of groundwater table as a result of tectonic changes in the southern plain of Nur Abad, as evidenced by the fact that the depth of the station was 89 meters less than 82 meters The highest drop in the Khomeghar well is about 26 meters in the southern part of the basin, in line with Kazeroon's active fault.
Mr Ali Mohammadpourzeidi, Professor Bohloul Alijani, Associate Professor of Climatology Mohammad Saligheh, Mr Mohammadsaleh Gerami,
Volume 19, Issue 52 (3-2019)
Abstract
owledge of spatial rainfall behavior in environmental, land planning is effective. These changes in the later place in the form of time later and in the climate of the area. The Target of this study was to reveal the presence or absence of precipitation trend in the ratio of the height of local precipitation behavior and identify province mazandarn. Therefore, the purpose of the rainfall data station 32 (Meteorological Agency and Department of energy), the statistical period 1988-2010. To get the regression analysis of precipitation process was used to identify the local behavior of precipitation, the method of spatial statistics were used. The results obtained from the behavior of precipitation, the existence of the process within the scope of the study and the emphasis is most consistent with the Be modified regression model at adjustment indicate. According to the regional behavior of precipitation, using local spatial statistics, spatial Moran well hot spots check this behavior. The results showed that precipitation in the province of Mazandaran has the pattern of clusters with high value. According to the local hot spots and methods Moran, West Coast up to a height of 700 m has positive z score and clusters with high value, 99% confidence level. This range includes 15% of the total of the province. The range of the Southern Highlands as well as the negative z score and clusters with low value with a confidence level shows 99%. This range is also about 20 per cent of the province's total. About 65 percent of the total area of the province as well as the lack of a significant trend show.
Mr Soleiman Pirouzzadeh, Mahmood Khosravi, Samad Fotohi,
Volume 19, Issue 52 (3-2019)
Abstract
Studies show that 14 provinces are impacted by wind erosion and the movement of sand dunes. The sand originated from the shores of Oman Sea is the most important environmental hazards that threaten the already large number of rural settlements. Sands of marine origin are available on the beach and away from the sea of dunes in addition of marine origin, Predictive models for planning sustainable use of land use and land cover in a country like Iran that land use is changing rapidly, there is an urgent need; To detect and predict changes in land cover changes overview to better manage natural resources and protect marginal lands beaches and is very effective long-term policy measures. The aim of this paper is modeling and prediction of changes in land-use in 2035 by using CA Markov model and Landsat satellite images in the West of Zarabad,( The coasts of Makran). Then to determine the changes in the movement of sand dunes in the study area ranged from twenty-three years (1991-2014), satellite imageries from Landsat 7 and 8(ETM+ sensor) with 15 and 30 meters spatial resolution , was used. The 1991, 2001and 2014 month August images were used, this images from website of the US Geological Survey (USGS) have been prepared. Finally, these images by using Geographic Information System (GIS), ENVI and IDRISI softwares were analyzed. The results showed that the changes in the region the largest increase in the interest of sand dunes in the year 1991 (25.561) km², in 2001 (10 . 568) km², and in 2014 (45.578), and the increase of (17.198) km², has experienced. The results also estimated that in future (2035) sand dunes area increase to 592.45 km².This increase in area of sand dunes occur in the absence of proper and efficient management is done in order to stabilize the sand. This increase resulted from changed moorland 162 km²of land area (27%) and 12 kilometers of vegetation (2%) and 23 km² of fluvial (3.4%). These changes makes heavily exposed about 6 villages (Karti,Gnjk, Sohroki, Pyvshk, Vanak and Kalirak) to the movement of running sands.
Mohamad Hadi Setavand, Fazel Hajizadeh, Hosin Yaghfoori,
Volume 19, Issue 52 (3-2019)
Abstract
Urban Public Service structuring the form and nature of the physical, social and spatial city; Therefore injustice in how to distribute it, the structure, on nature of the city and class segregation affects urban areas and Urban management is faced with serious challenges. In the same vein, the main purpose of this study, Spatial analysis of enjoyment levels ten main areas of the Shiraz city of Urban service. The research method is descriptive-analytical and its type is practical. In collecting data library method and field has been used. The statistical population of ten main areas of the Shiraz city that according to the 10 overall index and 49 components crucial public services Assessed. For analysis and grading the urban districts from the view point of enjoing public services, some models including Fuzzy TOPSIS, VIKOR and WASPAS have been used and for reaching to a unified result in data analysis of different models, the blended average of ranks has been used. The results of this method showed that Areas 1, 2 and 4 have in the first rank, areas 3, 6 and 7 in the category semi, Districts 8 and 10 low Enjoyment and Zones 5 and 9 enjoyment been lacking in class. The findings of this study show that the distribution of public services in areas of City Shiraz with Spatial justice approach does not match .At the end of this article, strategies according to research findings been proposed.
, , ,
Volume 19, Issue 52 (3-2019)
Abstract
The heat waves today are one of the most important climatic hazards in the world. According to many scientists, the Severe and frequent occurrence of heat waves in recent years has been due to the emission of greenhouse gases and consequent increased global warming. The purpose of this study is to investigate changes in the frequency and intensity of heat waves As well as their relationship with Global land-ocean temperature anomalies and greenhouse gases in the north-west of Iran. At First, maximum temperature of two meters of the surface during the period from 1851 to 2014 for 164 years was obtained from NASA’s website, then the maps of heat waves was drawn and extracted. Then, we analyzed and evaluated the frequency and severity of the heat waves, as well as changes in the annual, decade, fifty years old fluctuations and their centenary were analyzed. To achieve the research objectives, Pearson and Spearman correlation methods, linear and polynomial regression and non-parametric Mann-Kendall test were used. The results showed that the frequency of occurrence of heat waves in the considered period interval is incremental and relevant, and the most frequency of occurrence was in decades. Also the intensity of the heat waves is associated with a relatively significant increase, and the most intense heat waves occurred in the decades of the late 20th and early 21st century until the present period. The results of the correlation coefficients indicated that the intensity and frequency of the heat wave incidence have a positive and significant correlation with the Global land-ocean temperature anomalies. The results of investigating the relationship between frequency and intensity of heat waves with 4 important greenhouse gases, including: (CO2, CH4, N2O, SF6), showed that, except for the positive and significant correlation of carbon dioxide gas with the most severe heat waves in June, There was no meaningful relationship between them. The results of the Mann-Kendall test indicate an incremental and significant increase in the frequency and intensity of heat wave events in the North-West region of Iran.
Hassan Mahmodzadeh, Sodabeh Panahi, Mahdi Herischian,
Volume 19, Issue 52 (3-2019)
Abstract
From the late twentieth century, human kind has found out that if he wants to obtain cost efficiently and continuous utilization of lands, it is better to execute this in a planned framework named management plan. Such idea is became as an introduction to monitor the land or utilization of lands. Monitoring lands means contribution of an optimized space for land utilization with realization of common upcoming and related to each other in the past, now and in the future.Therefore, the objective of this research is to select the suitable lands with monitoring lands of view in the city of Hamedan using a Multi-Objective Land Allocation method.The aim of Multi-Objective Land Allocation method use is to contribute selection of proper lands with monitoring approach based on ideal levels concept which have been executed by 3 different ecologic, socio-economic and strategic aspects existing in the territory.The examined use include agricultural use (water system or dry farming), pasturing use and urban use which based on the highest weight of independent variables, the area has been allocated to mentioned use with land monitoring approach.In what follows, the land suitability map is obtained through MCE operation for each type of land use and the obtained land suitability areas were calculated using these maps for which the results are as follows: irrigated agriculture with 601.176 hectares, dryland farming with 961.193 hectares, urban suitability with 762.984, and rangeland management suitability with 960.552 hectares which is an important criterion for determining the area for implementing MOLA.In the next step, it was time for implementing MOLA module for resolving the contradictions among the uses.The results of MOLA showed that in average for the three studied aspects, the maximum area was associated with dryland farming with 364.4 hectares which is equivalent to 32% of the studied uses and the maximum weight of 0.4 was associated with irrigated agriculture.These resulted were obtained based on five factors (i.e. the current area of each land use, the favorable area for each land use based on MCE method, the occupational dependencies of different individuals to each land uses, prioritizing the ecological, economic, and social aspects of each land use).Finally, the results showed that selecting the suitable lands with spatial planning point of view using a Multi-Objective Land Allocation method is carried out properly through economic, social, and ecological aspects.
, , , ,
Volume 19, Issue 52 (3-2019)
Abstract
One of the Challenging problems of Tehran metropolitan region is Air pollution. Suburban expansion in the form of sprawl patterns have created the travels and transportations, due to the dependence on personal vehicles contributes more than 85 percent of creators of air pollution. The article studied the role of transportation in emergence of urban air pollution in Tehran metropolitan region, have population more than 15.98 million. The method of this paper is of analytical and is based on the secondary data and traditions of the Quantitative research methodology. This article have been wrote in the context of Retroductive strategy and meta-analysis method and compositional research traditions. For analysis of suburban spatial transportation have used Raw Data Intra-Urban and suburban Data in 1395 Year And for spatial analysis of air pollution (PM2.5 and PM10), have been used The raw data from sensing stations and Landsat satellite images (OLI) for three selected days in 1392, 1393, and 1395 as survey samples in the ArcGIS software. The research findings indicate that due to the intensity of transportation flows in Tehran metropolitan, the suburb to the suburb, the suburb to the central city (Tehran) and vice versa, Air pollution center Rise cannot be attributed to Tehran alone, as the area of pollutant sources has been distributed within the "Tehran metropolitan region ".So, the amount of spatial correlation between air pollution maps and transportation flow maps in selected days (2 Bahman 1392, 5 Bahman 1393 and Dec. 7, 1395), in all cases indicated high spatial relations (more than 75%), Confirmation the idea of this paper. Analysis of this situation in triple loops also shows that the highest volume of transportation is in the city of Tehran (CBD), suburban and exurban areas, respectively and the distribution pattern and spatial accumulation of pollution are also subject to this situation.
Mrs. Mina Ranjbar Fard, Ms. Hourieh Aarabi Moghaddam,
Volume 19, Issue 52 (3-2019)
Abstract
Nowadays almost all big cities are confronting heavy traffic and suffering from lack of parking lots which leads in traffic jam. According to the significant role of vertical parking in reducing the traffic load and smoothing the traffic current; this study was carried out with the purpose of presenting a decision support system for vertical parking site selection for mechanical and constructive parking lots by using Fuzzy-DANP method. Each criterion’s correspondent GIS data was acquired from Tehran Municipality for district no.3, 6, 7, 10, 11 and 17 which were chosen according to the corresponding mayors’ opinions of those districts and converted into its specific layer. Each criterion’s weigh was exerted to its determined GIS layer and eventually all those layers were integrated with each other. The final map of GIS output demonstrated a spectrum which determined the most appropriate to inappropriate locations to establish a parking of each type. The final results were shown within a user interface, including the GIS map and the estimated location of the chosen district and parking type. The overall steps mentioned above are forming the DSS of the study. The results showed that setting up mechanical parking in districts no. 3, 6 and 7 is proper. For building constructive parking; all districts are appropriate.
Mr Asdollah Hejazi, Mrs Fatemeh Khodaie Geshlag, Mrs Leila Khodaie Geshlag,
Volume 19, Issue 53 (6-2019)
Abstract
Varkesh
-Chai River with approximately 69 kilometer and north-south trend, in one of the main and permanent rivers of Tabriz city, That 10 villages with worn out texture have established in its main bed. Field studies show that, villages’development has been without knowing the rules governing hydraulic behavior, prediction of river hydrological behavior, and no respecting the main bed of river, it has been conserved to the agricultural land or garden. Lack of knowledge and attention to the above-mentioned cases and river bed manipulation has increased the vulnerability of villages, agricultural land or other human facilities of the flood risk in the catchment area. Therefore, it is necessary to study the areas potential to the flood occurrence and to prepare floodplain maps in district. In present study, flood levels were determined along the main river, during the return periods of 25 and 50 years. For this purpose, geography information systems (GIS) and HEC_RAS model and HEC_GEO_RASextension were usedto simulate earth geometry, river plans, left and right rivers shores, and flow rate obtained then, the villages exposed to flood with these return peaks were identified and then, hydraulic behavior of the river was simulated. Finally, solution to reduce the damages caused by flood along the main river were identified.
Dr. Mohammad Javad Vahidi, Dr. Rasoul Mirabbasi,
Volume 19, Issue 53 (6-2019)
Abstract
In order to protect soil and water resources should be identified erodible areas of watersheds, to be able to prevent land degradation and to control erosion in the form of soil conservation planning or watershed management. Therefore, the present study aimed to classification and delineation of susceptible areas to water erosion in the Hervi watershed using Hjulstrom curve, has been conducted. Increasing of accuracy, speed and facility of spatial achievement, using GIS technology, are advantages of the present study. In this study, were separated 10 sub-watersheds based on the feeding levels of streams. Spatial variability of soil properties in sub-watersheds, such as texture and the mean diameter size of the particles using hydrometer method were measured; also the maximum potential velocity of outlet in sub-watersheds based on the characteristics of each sub-watershed were calculated. Then, status of erosion and sediment in watersheds and sub-watersheds was studied using Hjulstrom curve (based on the mean diameter size of sediment particles and the maximum potential velocity of outlet), and was comparatively classified in term of erodibility. Finally, delineation map of susceptible regions to water erosion in the study area were obtained. The results revealed that the upstream and side areas of the watershed including: Sub-watershed No.4 (8.94% of the land), has very high erodibility, and Sub-watersheds No.1 and No.9 (36.94% of the land) have high erodibility. These areas are steep and often devoid of vegetation or have poor vegetation (such as poor pastures and rain-fed farming); so, it is necessary a proper strategy to prevent further erosion.
Dr Batool Zeinali, Sima Khalili, Saideh Eiyni,
Volume 19, Issue 53 (6-2019)
Abstract
The aim of current research is atmospheric hazards climate zoning in Iran Northwest. So meteorological organization data were used in cases such as mean temperature , minimum temperature , maximum temperature, precipitation in monthly and daily scale for 13 synoptic stations in range of East Azerbaijan province, West Azerbaijan province) and Ardebil province during 26 years. (1990-2015) in this research , it was investigated 10 main atmospheric hazards such as famine or drought , hailstone,, heavy snow , thunder storm, severe precipitation, margin precipitation , blizzard , fogging , dust storm in range of Northwest bound. Then happening frequency maps were prepared with separating form for hazards by using Geographic information system. (GIS) Also spatial zoning maps were prepared for every class. Finally by combining all of hazards investigation; it was prepared Northwest region atmospheric hazards extensive map. Results show that, East, Southeast, center and West parts in Northwest region are located among most hazard zones based on happening frequency. But Northeast parts and zones have the least hazards. Also results express that blizzard and dust storm are main atmospheric hazards at Northwest regionThe highest hazard frequency in Northwest region relate to blizzard with 4148 hazards during 1990-2015 study period. The highest blizzard frequency in Ahar station is observed with 514 hazards. The second hazard in Northwest relate to dust phenomenon with 1948 cases. The highest frequency of mentioned case was observed in Maragheh station with 410 hazards. The third case in Northwest relate to thunder storm phenomenon with 1773 hazards. The sixth case relate to icing phenomenon with 1315 hazards meaning. The highest icing frequency is observed in Khalkhal station with 144 hazards. The seventh case relate to hailstone phenomenon at Northwest with 341 hazards. The highest of hailstone frequency is observed in Maragheh station with 56 hazards. The eighth case relate to fogging phenomenon with 333 hazards. The highest of fogging is observe in Ahar station with 135 hazards. The ninth case relate to famine or drought phenomenon at Northwest with 168 hazards. The highest of famine or drought frequency is observed in Urmia and Ardebil stations with 16 hazards totally. The highest margin precipitation is observed in Parsabad station with 19 hazards. The lowest frequency of margin precipitation relate to Makou and Khalkhal stations with 4 hazards totally.
Dr. Ali Bayat, Mr. Saeed Mashhadizadeh Maleki,
Volume 19, Issue 53 (6-2019)
Abstract
Precipitable Water Vapor (PWV) is one of the most important quantities in meteorology and climate studies. PWV in Earth's atmosphere can be measured by Sun-photometer, the Atmospheric Infrared Sounder (AIRS), and radiosonde from surface, atmosphere and space-based systems, respectively. In this paper, we use PWV measured by Sun-photometer located in Institute for Advanced Studies in Basic Sciences (IASBS), AIRS and 29 Iranian synoptic stations data include temperature, dew-point temperature, pressure and relative humidity. For validation of AIRS data, the correlation coefficient between AIRS and Sun-photometer data calculated. The correlation is 90%. Average of PWV measured with sun-photometer and AIRS are 9.8 and 10.8 mm, respectively. Pearson's correlation coefficients between PWV of AIRS data set and temperature, dew-point temperature, pressure and relative humidity for synoptic stations are calculated. Correlation between PWV and temperature, dew-point temperature, pressure, and humidity are 73%, 74%, -40% and -30%, respectively. PWV and temperature correlation coefficient map shows a positive trend between latitude and correlation coefficient. Rising a degree in latitude lead to increasing 2.8 percent in the correlation coefficient.
