Hydrology
Mahnaz Rezaei; Somaiyeh Khaleghi; Mohammad Mahdi Hosseinzadeh
Abstract
Considering the importance of the subject, in this research, the factors affecting the hydrological changes of the Taleghan River have been investigated. Descriptive-analytical methods have been used in this research. The most important data of the research included Landsat 5 and 8 satellite images, ...
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Considering the importance of the subject, in this research, the factors affecting the hydrological changes of the Taleghan River have been investigated. Descriptive-analytical methods have been used in this research. The most important data of the research included Landsat 5 and 8 satellite images, the SRTM 30-meter height digital model, Taleghan synoptic station climate information, and regional discharge information. Also, the most important tools used in the research were ArcGIS, ENVI, and SPSS. According to the subject of the study, this research has been done in several stages. In the first stage, the evaluation of land use changes, in the second stage, the evaluation of changes in climatic elements, and in the third stage, using IHA indicators, has been paid to evaluate the hydrological changes of the Taleghan River. The results of this research have shown that during the years 2000-2017, the average temperature of the region has increased and the area covered by snow has decreased. Also, under the influence of population growth, the use of artificial areas has increased and the use of gardens and pastures has decreased. Also, the total results of this research have shown that the discharge of the Taleghan River under the influence of natural and human changes, in terms of all IHA indicators, has had a significant decreasing trend. Also, among the stations in the region, the Glink station, which is located downstream of other stations, has faced more changes, which can be considered as the result of human activities and climate changes.
Hydrogeomorphology
Mohammad Mehdi Hosseinzadeh; Ali Reza Salehi Milani; Fateme Rezaian Zarandini
Abstract
Floods, as natural and unexpected events, have occurred frequently in recent decades. To reduce the damages caused by floods and flood management, it is mandatory to assess the possibility of danger and prepare maps of possible danger zones. In recent decades, many destructive floods have occurred in ...
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Floods, as natural and unexpected events, have occurred frequently in recent decades. To reduce the damages caused by floods and flood management, it is mandatory to assess the possibility of danger and prepare maps of possible danger zones. In recent decades, many destructive floods have occurred in the Nakarod catchment. Because of this, to manage floods, reduce damages, and properly use water resources, the flood potential of the sub-basins of the Nakarod catchment has been studied. Neka River is 176 km long, and it is one of the important rivers of Mazandaran province and one of the catchments of the Caspian Sea. In this research, to prepare a map of the sensitivity of the sub-basins to the flood risk of the basin, 11 influencing parameters have been used, which includes elevation, slope, distance from drainage network, drainage density, flow accumulation, rainfall, land-use, geology, stream power index, topographic wetness index and curvature of the topography. The layers were weighted using the Analytical Hierarchy Process (AHP); and eventually, by using the weighted linear combination method in ArcGIS software, the standardized layers were multiplied by the corresponding weight, and then the results of all the variables were added and accumulated together, and the final sensitivity map was divided into five classes. The results of the research indicate that flood sensitivity is different in the sub-basins of the Neka RiverAmong the effective environmental factors in flooding, the elevation and stream density were the most influential factors in the flood risk of the Neka catchment.
hydrogeology
Zahra Yunesian; fariba hemmati; Mohammad Mahdi Hossein Zade
Abstract
are connected at the end of the basin and form the Darbadam River. According to the results obtained for the central angle, in the first part between 2010 and 2021, the Meandri River pattern was developed and there was no change in the pattern class, but in the second and third parts in 2010, the river ...
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are connected at the end of the basin and form the Darbadam River. According to the results obtained for the central angle, in the first part between 2010 and 2021, the Meandri River pattern was developed and there was no change in the pattern class, but in the second and third parts in 2010, the river pattern is not developed meandering, which in 2021 has become the developed meandering river patternBased on the average curvature coefficients in all three sections studied, the Darbadam River has a meandering pattern. Due to the characteristics of the region, such as the presence of resistant rock layers, the high slope of the region and also the mountainous topography, has led to low transverse displacement of meander in the region. However, in some parts of the river, due to human activities, including land use change, vegetation degradation and overgrazing, there has been a change in the river pattern.
