پژوهشی
Geomorphology
leila aghayary; sayyad Asghari Saraskanrood; Batool Zeynali
Abstract
Text Landslides are one of the types of large-scale processes that cause many human and financial losses in many parts of Iran and the world every year. The increase in population and the expansion of human settlements in mountainous areas, the difficulty of predicting the occurrence of landslides ...
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Text Landslides are one of the types of large-scale processes that cause many human and financial losses in many parts of Iran and the world every year. The increase in population and the expansion of human settlements in mountainous areas, the difficulty of predicting the occurrence of landslides and the numerous factors influencing the occurrence of this phenomenon, reveal the necessity of landslide risk zoning. Identifying the effective factors in the occurrence of this phenomenon and its risk zoning is one of the basic and practical methods to achieve its forecasting, control and monitoring solutions. By using field studies, geological and topographical maps, and by reviewing the researches and studies done in this field, as well as examining the existing conditions in the studied area, 9 factors of elevation, slope, slope direction, lithology, distance from the fault. , the distance from the river, the distance from the communication roads, land use and rainfall were investigated as factors affecting the occurrence of landslides. Therefore, the purpose of this research is to investigate and analyze the most important factors involved in creating the risk of landslides in Garami city and to identify the prone areas that will probably be involved in landslides in the near future. In this research, the zoning of prone areas was done with the Aras multi-criteria algorithm in the Edrisi software environment, and according to the results of landslide risk zoning; The criteria of land use, slope, and lithology are the most important factors involved in creating the risk of landslides in the study area with weight coefficients of 0.187, 0.152, 0.152, and 0.142, respectively, and are 361.99 and 450.32, respectively. A square kilometer of the area has a very high probability of danger. Finally, it can be said that the most important factor involved in increasing the amount and potential of landslides in Germi city is the change of land use and the increase of agricultural land and livestock pastures.
پژوهشی
Hydrology
fatemeh ghavidel; Majid R.Banafsheh; Gholam Hasan Mohammadi
Abstract
The purpose of this research is to investigate the temporal changes and spatial distribution of the total cloud cover of the sky in the Ormia Lake drainage basin. In order to achieve the goals of this research, observational data on total cloud cover of the sky at five selected meteorological stations ...
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The purpose of this research is to investigate the temporal changes and spatial distribution of the total cloud cover of the sky in the Ormia Lake drainage basin. In order to achieve the goals of this research, observational data on total cloud cover of the sky at five selected meteorological stations and the product of total cloud cover of the sky (CFFCM) from MODIS sensors (Tera and Aqua) were used. The observed cloudiness values according to the ICAO standard were classified into five classes: cloudless sky, slightly cloudy, partly cloudy, semi-cloudy, and full cloudy, and the sky cloudiness changes were investigated. Pearson's correlation test was also used in order to investigate the relationship between the total cloud cover of the sky and the elements of precipitation, temperature, evaporation, and sunshine hours.The findings of the research showed that in the study area, the sky is mostly clear (28.7%) and slightly cloudy (23.9%), and only about 30% of the cases are semi-cloudy and full cloudy.In the examination of the frequency of occurrence of each of the cloudy classes, it was found that, in most cases, there was an increasing trend in the clear and slightly cloudy classes and a decreasing trend in the semi-cloudy and full cloudy classes.The study of the correlation coefficients between the total cloud cover of the sky and climatic parameters showed that there is a direct and significant relationship between the cloudiness of the sky and annual precipitation and an inverse relationship with temperature, evaporation, and sunshine hours, which is weaker in the case of annual temperature than the rest of the parameters, and also that the relationships established with observational data are more logical than those established with those established with satellite data. Investigating the spatial distribution of average seasonal cloudiness showed that cloudiness in winter and autumn is different from spring and especially summer. The highest amount of winter (summer) cloudiness is observed in the southern (northern) half of the Ormia Lake drainage basin, and this arrangement is consistent with the seasonal synoptic currents and the distribution of altitudes.
پژوهشی
Geomorphology
Jamshid Yarahmadi; Mohammad Khosroshahi
Abstract
The extended periods of drought, decrease in vegetation, and enlargement of the salt playa at Lake Urmia have resulted in the formation of local dust hotspots on the periphery of Lake Urmia in East Azarbaijan province. The objective of this study was to examine the spatial and temporal distribution of ...
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The extended periods of drought, decrease in vegetation, and enlargement of the salt playa at Lake Urmia have resulted in the formation of local dust hotspots on the periphery of Lake Urmia in East Azarbaijan province. The objective of this study was to examine the spatial and temporal distribution of wind erosion in East Azarbaijan province using the DSI index. To achieve this, a set of weather data recorded over the past 30 years at specific codes in meteorological stations was compiled. Subsequently, the Mann-Kendall test was employed to assess the presence of a trend in the data series. Following this, the frequency of dust storms was calculated using the DSI index, and a spatial distribution map was generated in the GIS. The results of the Mann-Kendall test indicated that the slope of the trend for both local and extra-local dust storms in the province is on the rise. However, only the trend in extra-local dust storms is statistically significant at the 95% confidence level. The findings of the research revealed that the majority of the observed dust storms originate from outside the local area in East Azarbaijan province. Nevertheless, there has been a relative increase in the frequency of local dust storms in recent years, which can be attributed to the prolonged droughts resulting in reduced vegetation and the expansion of the playa of Lake Urmia. In this context, the highest frequency of dust storms has been observed at the Tabriz, Sahand, and Maragheh meteorological stations near Lake Urmia.
پژوهشی
Hydrogeomorphology
Masoumeh Rajabi; Fatemeh Rangraz Forough
Abstract
There are various types of tourism depending on the motivation for travel, one of which is health tourism. Health tourism has grown significantly in recent years due to the spread of machine life and psychological pressures. This type of tourism includes individuals and groups who travel for medical ...
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There are various types of tourism depending on the motivation for travel, one of which is health tourism. Health tourism has grown significantly in recent years due to the spread of machine life and psychological pressures. This type of tourism includes individuals and groups who travel for medical treatment, such as using mineral and warm waters, spending time in recovery, and so on. As one of the natural resources, hot springs are a part of health tourism that are used to treat various medical conditions. The current research focuses on the hot springs of East Azerbaijan province. The study is descriptive-analytical in terms of methodology and applied in terms of purpose. Due to its geographical location, climatic features, and geological and tectonic conditions, East Azerbaijan province is considered one of the important centers of hot springs, which are concentrated around Sahand mountain and Bozgoush mountain range in the northeast of Kalibar. This research uses the Comanescu method, library research, Internet-based surveys, documentary studies, and surveys of 20 experts from the Regional Water Organization and the Provincial Tourism Department, Motalleq Hot Springs, Bostan Abad, Asbforoushan, Allah. Haq, Isti Su Liqvan, Yel Sui, Top Tapan, and Dash Alti were selected and evaluated. The results revealed that the Motalleq Hot Spring, with a total score of 86, has the highest score among the eight selected springs. The Asbforoushan hot spring comes in second with 84 points, the Yel Sui hot spring comes in third with 82 points.
کاربردی
Bromand Salahi; Mahdi Foroutan
Abstract
Monitoring the changes and fluctuations of precipitation in geographical areas can give a better view of the behavior of this phenomenon in the coming years. The purpose of this research is to investigate the precipitation situation in Ardabil Plain (Ardabil, Bileh-Daragh, and Kolour stations) and forecast ...
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Monitoring the changes and fluctuations of precipitation in geographical areas can give a better view of the behavior of this phenomenon in the coming years. The purpose of this research is to investigate the precipitation situation in Ardabil Plain (Ardabil, Bileh-Daragh, and Kolour stations) and forecast it in the coming years based on the output of CMIP6 models by the CMhyd downscaling model. Then, using R2, MAE, MSE, RMSE, and Taylor diagram, the observational data of the base period were compared with the historical data of 5 GCM models from CMIP6, and the best model was selected for each studied station. The output of the top models was corrected for skewness by linear scaling method and based on SSP126, SSP245, and SSP585 scenarios, the precipitation of 2050-2023 for each station, forecast, and its trend were drawn with the Mann-Kendall statistic. The results showed that in the eastern and western areas of Ardabil Plain (leading to the heights of Talesh and Sablan mountains), the rainfall changes were increasing (2.80 mm). In the Ardabil station, the MIROC6 model with a correlation coefficient of 0.94%, and in Bileh-Daragh and Kolour stations, the MPI-ESM1-2-HR model with a correlation coefficient of 0.88% and 0.92%, respectively, have the highest accuracy in simulating the precipitation. Also, the results of the scenarios showed that the precipitation changes in Ardabil station in the future period compared to the base period under the SSP126, SSP245, and SSP585 scenarios will be 0.24, -6.36, and -2%, respectively.
پژوهشی
Hydrology
Raoof Mostafazadeh; Mostafa Zabihi Silabi; Mohamad Kazemi
Abstract
The increasing human needs and changes in climate patterns have led to the construction of water storage structures to meet the water demand in many regions worldwide, including Iran. Consequently, the hydrological regimes of rivers in various parts of Iran, due to human activities such as dam construction, ...
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The increasing human needs and changes in climate patterns have led to the construction of water storage structures to meet the water demand in many regions worldwide, including Iran. Consequently, the hydrological regimes of rivers in various parts of Iran, due to human activities such as dam construction, have undergone alterations in recent decades. Understanding the effects of dams on river hydrological regimes is essential for river flow management and the preservation of river ecosystems. In this regard, the present study assesses the changes in the health of the Urmia's Shahrchai River flow during three periods: pre-dam construction, dam construction, and dam operation, from 1951 to 2017, through calculating different flow health related indices. The results indicate that the deviation of all hydrological health sub-indices in the post-dam construction period is higher than the pre-dam construction period. Moreover, the deviation of flow regime sub-indicators was predominantly low to moderate until 1998 and varied from low to very high after 1998. Additionally, the highest deviation of studied flow health-related indices occurred during the reference and dam operation periods for flood occurrence and minimum monthly flow, respectively, while during the dam construction period, it pertained to minimum monthly flow. Furthermore, the findings suggest that the hydrologic health of Shahrchai River flow decreased by approximately 16% and 45% during the dam construction/operation periods, respectively, compared to the reference period. The results of this study can be utilized in the understanding of flow alteration and the sustainable regulation of the Shahrchai River flow regime.
پژوهشی
Geomorphology
Maryam Bayati Khatibi; Behrooz Sari Sarraf
Abstract
Today, following the drying up of Lake Urmia, new centers for wind erosion activity have been formed in the northwest of the country, and these centers have become the source of dangerous dust production. In the southeastern part of Lake Urmia, the formation of wind erosion centers can lead to irreparable ...
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Today, following the drying up of Lake Urmia, new centers for wind erosion activity have been formed in the northwest of the country, and these centers have become the source of dangerous dust production. In the southeastern part of Lake Urmia, the formation of wind erosion centers can lead to irreparable damages from the point of view of nature and human health. In this study, in order to identify wind erosion centers, changes in the water level of Lake Urmia based on the fluctuation pattern of climatic parameters using data The long-term effects of the existing stations in the Urmia Lake watershed were investigated. In order to identify the origin areas of fine walnut production and track dust storms in the studied area, horizontal visibility data below 1000 meters of meteorological data and Lagrangian HYSPLIT model in retrograde mode were used at different stations and at different levels of the atmosphere. It was used regularly and also the highest amount of dust containing 26 pressure tsars (100-1000 hectopascals) and available with a time step of 12 hours. At the same time as the first dust entered the study area, the wind direction was investigated for 24 hours before that. In the studied area (Banab and Malekan cities), the focus of wind erosion was investigated using AOD data from MACC database with a spatial accuracy of 0.125 × 0.125 geographic degrees and a daily time scale. In this study, MODIS Terra and Aqua satellites with a wavelength of 550 nm were used to generate AOD data. Day-by-day review of MODIS satellite images and the implementation of the fine dust characterization index revealed the occurrence of specific dust storms over Urmia Lake and southeast of the lake on different days. Investigations showed that extensive salt dust spreads in all parts of Lake Urmia, including the southeast of the lake in the limits of Bonab city, and the dust in this part is spread in the bed of atmospheric currents to the east and southeast for a distance of more than 140 km. In the northeast direction, they spread over 150 km in 12 hours.
پژوهشی
Hydrogeomorphology
Aghil Madadi; sayyad Asghari Saraskanrood; Hossein Hajatpourghaleroodkhany
Abstract
Monitoring of land use changes and destruction of vegetation as one of the dominant parameters in soil erosion is one of the important issues for assessment and control in natural resource management. The Hyrcanian forests of Gilan province, over the past years, have deteriorated due to neglect and have ...
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Monitoring of land use changes and destruction of vegetation as one of the dominant parameters in soil erosion is one of the important issues for assessment and control in natural resource management. The Hyrcanian forests of Gilan province, over the past years, have deteriorated due to neglect and have taken on a different face. So; The purpose of this research is to reveal the changes in land use and the destruction of forest cover and its effects on soil erosion in the watershed of Ghaleroodkhan Fuman. For this purpose, the changes in land use that took place between 1371 and 1402 were extracted using Landsat images and object-oriented classification techniques and were classified (agriculture, forest, pasture, water, and residential). In the next step, by identifying the effective factors in the erosion of the area and preparing the information layers of each criterion in GIS, the standardization of the layers was done using the fuzzy membership function, the weighting of the criteria using the CRITIC method and the final modeling was done using the MARCOS multi-criteria analysis method. The study of the changes in watershed use shows that the forest cover in 1992, with an area of 222.17 square kilometers, had the largest area among the land uses, and in 2023, its area decreased to 205.03 square kilometers. Also considering the results; Residential use with an increase of 27.17 square kilometers has changed the most during the 30 years of study. According to the erosion zoning map, respectively; The area of the floor with very high and high erosion potential has increased from 18.04 and 31.05 percent in 1992 to 22.52 and 32.34 percent in 2023. According to the obtained results, it is possible to reduce the forest cover and convert it into residential areas, agricultural lands, and pastures, as well; He considered the conversion of agricultural lands to residential areas and the increase of residential and agricultural use in the boundaries and riverbeds as the most important factors involved in increasing the soil erosion potential of the basin.
