پژوهشی
RS
Abstract
Changes in land cover and land use due to human activities have left adverse effects on the environment. The eastern regions of Ardabil province are a clear example of this phenomenon. The purpose of this research is to analyze spatial and temporal changes in land cover and land use and its effects on ...
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Changes in land cover and land use due to human activities have left adverse effects on the environment. The eastern regions of Ardabil province are a clear example of this phenomenon. The purpose of this research is to analyze spatial and temporal changes in land cover and land use and its effects on the temperature of the surface of the earth in Lake Neor. To estimate land use and land cover, random forest models (RTC), maximum likelihood model (MLC) and support vector machine (SVM) were used and the efficiency of each was estimated by the Kappa coefficient and it was observed that the SVM model has the highest Kappa coefficient (0.87) Bands 6, 5 and 10 of Landsat 8 were also used to extract the LST index, and it was observed that the western part of the lake faced an increase in the temperature of the earth's surface. During the time period of 2002, 2013 and 2022, significant changes were observed in the water area of Neor Lake and its nearby vegetation. Barren lands had the largest extent in all studied periods. Vegetation has increased by 1.04 square kilometers based on SVM model. The surface area of the lake was estimated as 3.19 square kilometers based on the MLC model in 2002. The area of the water zone in the MLC model has decreased by 1.56 square kilometers between 2002 and 2022, and this decrease is 0.67 and 0.69 square kilometers for the RTC and SVM models, respectively.
پژوهشی
RS
Abstract
Extraction of the water zone in the western parts of Afghanistan through remote sensing images is an efficient way to investigate and monitor water resources and its impact on the water resources of eastern Iran, especially the wells of Sistan and Baluchestan. In this research, from OLI sensor of Landsat ...
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Extraction of the water zone in the western parts of Afghanistan through remote sensing images is an efficient way to investigate and monitor water resources and its impact on the water resources of eastern Iran, especially the wells of Sistan and Baluchestan. In this research, from OLI sensor of Landsat 8 satellite and TM sensor of Landsat 5 satellite, Normalized Difference Water Index (NDWI), modified Normalized Difference Water Index (MNDWI), normalized difference moisture index (NDMI), automated water extracted index (AWEI), new water index (NWI), and water ratio index (WRI) have been used to extract water areas. In the worst case, the area of the Arghandab dam has decreased by only 2.44 km upstream and the NDMI index has shown an increase of 0.65 square km in the moisture resources of this dam. However, the surface of the well in the southern half of Zabul has decreased from 55.94 square kilometers to 17.82 square kilometers, which shows a decrease of 38.12 square kilometers. This shows a sharp decrease in the level of the semi-well. This has caused more heat to be emitted in the dry areas. But the minimum temperature has decreased from 17.47 degrees to 11.87 degrees Celsius, which has experienced a decrease of 1.95 degrees Celsius. The LST index has a negative correlation with all the indices and the highest correlation with the NWI index was -0.941 in 1994. The lowest correlation was also obtained at the rate of -0.65 related to the NDMI index.
پژوهشی
RS
mehdi feyzolahpour
Abstract
Drought is the most expensive weather event in the world after hurricanes. Early detection of drought and prediction of its occurrence will reduce costs and save human lives. In this research, in order to evaluate the best index in estimating moisture stress and drought, 8 indices NDVI, NDWI, VCI, SR, ...
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Drought is the most expensive weather event in the world after hurricanes. Early detection of drought and prediction of its occurrence will reduce costs and save human lives. In this research, in order to evaluate the best index in estimating moisture stress and drought, 8 indices NDVI, NDWI, VCI, SR, MSI, SIWSI, NDII and NMI were used and Shadgan Wetland was investigated in the period of 2018 to 2023. LST index was also used to check temperature changes. In order to determine the most suitable index, the Pearson correlation coefficient was estimated between the indices and the effectiveness of each index was shown on the Chadwick scale. Based on this, NDWI, MSI, NMI and LST indices have the highest correlation and based on Chadwick's scale in 5 cases, NDWI and MSI indices have a strong and very strong correlation and there is a strong correlation between these two indices at around 0.99 - It has been established. The correlation between LST and NDWI indices was also negative and was estimated at -0.73. Due to the dominance of semi-arid conditions in the region, vegetation-based indices have a very weak capability in drought estimation, and the correlation between NDVI and NDWI was around 0.05. Therefore, based on this, it can be concluded that in Shadgan wetland, indicators based on humidity and temperature stress have better capabilities in drought estimation than vegetation indicators.
پژوهشی
Hydrogeomorphology
Mohammad Hossein Rezaei Moghaddam; Davoud Mokhtari; Tohid Rahimpour; Vahideh Taghizadeh Teimourloei
Abstract
Azarshahrchai catchment area, located on the western slope of the Sahand mountain range, is formed by the connection of numerous tributaries flowing in deep valleys, and every year in the spring season, with the onset of rains, floods occur in these valleys. The purpose of this research is to evaluate ...
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Azarshahrchai catchment area, located on the western slope of the Sahand mountain range, is formed by the connection of numerous tributaries flowing in deep valleys, and every year in the spring season, with the onset of rains, floods occur in these valleys. The purpose of this research is to evaluate the performance of the weighted evidence (woe) function for preparing the flood susceptibility map of the Azarshahr Chai catchment area. In order to reach the mentioned goal, first, the location of 82 flood catch points using Landsat8.c2.l2 satellite images based on the flood of April 2016 was randomly divided into two groups of 70% (57 flood catch points) for training data and 30 percent (25 points) flood) was used for validation data. Then 14 effective factors in flood occurrence elevation, slope, Aspect, slope curvature, distance to river, distance to road, river density, TWI (topographic moisture index), lithology, soil type, rainfall, and NDVI in Arc software environment and land use in ENVI5.3 software environment, analysis, and location of flood catch points in all 14 factors were investigated. The ROC operating characteristic curve was used to validate and correct the results obtained. The results of the research indicate that 19.56% of the basin is in the very high sensitivity class, 19.18% in the high sensitivity class, 24.61% in the moderate class, 21.94% in the low class and 14.68% in the shallow class in terms of flood vulnerability.
پژوهشی
RS
mehdi feyzolahpour
Abstract
Spatial and temporal changes of surface water affect the structure and functioning of the ecosystems of the Teham Dam region as well as the agricultural, economic and social development in this region. In this research, MNDWI, AWEI and NDWI indices and SVM support vector machine model was used to detect ...
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Spatial and temporal changes of surface water affect the structure and functioning of the ecosystems of the Teham Dam region as well as the agricultural, economic and social development in this region. In this research, MNDWI, AWEI and NDWI indices and SVM support vector machine model was used to detect the long-term changes of Teham Dam in the period from 2002 to 2023. The results of the AWEI index showed that the area of the dam was about 2.4 square kilometers in 2007, which decreased to 1.15 square kilometers in 2023. In the MNDWI index, in 2007 and 2023, the area of water was equal to 2.6 and 1.17 square kilometers, respectively. The NDWI map shows a 46.38% decrease in the area of the water zone from 2007 to 2023. But in the AWEI index, this decrease was equal to 47.9. AWEI index with kappa values equal to 0.94 has correctly recognized the boundaries of water areas. According to the SVM model, in this period of time, the amount of vegetation has decreased from 0.8 square kilometers in 2002 to 0.07 square kilometers in 2023. The amount of barren land has decreased almost in this period of time and was equal to 4.57 square kilometers in 2023. The maximum temperature of the earth's surface in July 2002 was equal to 38.3 degrees Celsius and in July 2023 it reached 28.4 degrees Celsius.
علمی
Geomorphology
sayyad Asghari Saraskanroud; Aghil Madadi; nazfar aghazadeh; Raoof Mostafazadeh
Abstract
Soil erosion is one of the significant environmental challenges that leads to the degradation and decline of soil quality. This study examines the impact of land use changes on soil erosion in the Givi Chai region. The use of satellite images (ETM+7 2010 and OLI 2022) as the primary tool for analyzing ...
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Soil erosion is one of the significant environmental challenges that leads to the degradation and decline of soil quality. This study examines the impact of land use changes on soil erosion in the Givi Chai region. The use of satellite images (ETM+7 2010 and OLI 2022) as the primary tool for analyzing land use changes and assessing soil erosion has been a crucial step in this research. The images were classified using an object-based method, identifying various land uses. These uses included residential areas, agricultural lands, barren lands, orchards, dense, medium, and sparse vegetation, and water bodies. The factors influencing the G2 model included R (rainfall), S (soil erodibility) , V (vegetation cover), T (topography) , and I (slope adjustment factor). An erosion map was created and analyzed. Results indicated an increase in residential areas and sparse vegetation while showing a decrease in orchards and medium vegetation cover. These changes directly impacted soil erosion. The amount of erosion in 2022 increased compared to 2010, with the highest erosion occurring in agricultural and barren land uses. The final erosion map indicated areas with very high and high erosion associated with agricultural land use, weak pastures, and residential areas. The increase in agricultural and barren lands and the decrease in vegetation cover were identified as the main factors contributing to soil erosion. The study shows that changes in land use, particularly the increase in residential and agricultural areas, have a negative impact on soil erosion.
پژوهشی
Hydrology
zohreh khorsandi Kouhanestani; Fatemeh Taatpour
Abstract
Rainfall-runoff processes are among the most complex and nonlinear phenomena in hydrology. In water resources management, runoff forecasting faces challenges in ungauged watersheds.In this study, the efficiency of lumped models and machine learning methods was investigated in the Kabkian watershed, that ...
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Rainfall-runoff processes are among the most complex and nonlinear phenomena in hydrology. In water resources management, runoff forecasting faces challenges in ungauged watersheds.In this study, the efficiency of lumped models and machine learning methods was investigated in the Kabkian watershed, that is one of the principal branches of the Karun River. AWBM, Sacramento, SIMHYD, TANK, and SMAR Also, some algorithms in decision trees, artificial neural networks, and support vector regression were applied to simulate daily and monthly runoff in the Kabkian watershed. Monthly and daily discharge, precipitation, and potential evapotranspiration for the period between 1972 and 2022 were used,. The accuracy and efficiency of the methods were examined using R², the Nash-Sutcliffe coefficient, and RMSE. Results showed that SMAR and AWBM, in comparison to other lumped models, have the best efficiency in the simulation of daily discharge in the Kabkian watershed. The Nash-Sutcliffe coefficients for them in the test stage are 0.79 and 0.78, respectively, showing that these models have good efficiency in daily discharge simulation. Also, the SMAR and AWBM models' Nash-Sutcliffe coefficients are 0.71 and 0.72, respectively, and the R2 for the two models is 0.79 in the monthly time series. These values show that these models have good efficiency. In machine learning methods, in the daily series, the random forest algorithm's R2 is 0.61 and has the best efficiency in comparison to other methods. Also, in the monthly series, the random forest's R2 is 0.93, which illustrates good discharge simulation efficiency.
پژوهشی
watershed
Mahnaz Saber; Bromand Salahi; Roghayeh Maleki Meresht
Abstract
The SWAT model was used in this research to simulate the hydrological conditions of the Aras River basin in the future period. The model was calibrated based on the data of 1987-2006 and its validation was done in 2007-2014 with the SUFI2 algorithm and the SWAT model was calibrated based on the monthly ...
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The SWAT model was used in this research to simulate the hydrological conditions of the Aras River basin in the future period. The model was calibrated based on the data of 1987-2006 and its validation was done in 2007-2014 with the SUFI2 algorithm and the SWAT model was calibrated based on the monthly flow rate of the selected hydrometric station. After selecting the optimal parameters and running the simulation in 350 simulator rounds, the values of the evaluation criteria were obtained in the calibration period and in the validation phase. To evaluate the water balance changes of the basin under the conditions of climate change from the downscaled data of the CNRM-CM6 climate model in the historical period (1985-2014) and the future period (2025-2100) under the SSP5-8.5 scenario were used as input data to the SWAT model. The findings showed that evapotranspiration of the Aras basin has wasted a large share of the precipitation of 272mm in the historical period and 351 mm in the future period of the basin, and the amount of infiltration and lateral flow, which are necessary to feeding underground and surface resources, is very low. Also in terms of land use, the minimum ET of the basin was calculated in the use of good pastures. Also, the findings showed that although in the future period the annual rainfall will be 79 mm more than the historical period, but a major part of it will be spent on evapotranspiration in the months of May to July.
پژوهشی
Hydrology
Leyla Babaie; Hirad Abghari; Raoof Mostafazadeh
Abstract
The occurrence of low flow and high flow periods in watersheds is a part of a river's regime. In recent years, changes in river flow and its intensification have impacted the production and utilization of river flows as well as water management, making it an important area of study. Evaluating various ...
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The occurrence of low flow and high flow periods in watersheds is a part of a river's regime. In recent years, changes in river flow and its intensification have impacted the production and utilization of river flows as well as water management, making it an important area of study. Evaluating various characteristics of the flow regime of natural rivers can help understand how river discharge changes due to climatic. In this study, changes in high flow and low flow indices at the Bitas watershed, Mahabad-chai, which monitors a naturally flowing river upstream of Mahabad Dam, were assessed for the period from 1963 to 2020. The results indicated that the Number Spell index was 144 during high flow periods and 253 during low flow periods. The Single Longest index was 1,635 for low flow periods and 163 for high flow periods. The average peak flow and average duration of peak flow indices for high flow periods were 22.6, and for low flow periods, they were 0.33. Additionally, the mean duration was 29.6 for high flow and 54.82 for low flow. According to the results, the total duration index for high flow periods fluctuated between 3 and 163, while the total duration index for low flow was 241. The findings of this study can be used to better understand changes in the natural flow regime, variations in the timing and frequency of low and high flow events, and ultimately to optimize the management of inflow to Mahabad Dam.
پژوهشی
Hydrogeomorphology
Sayyed Hojjat Mousavi
Abstract
Problems of watersheds and their water resources require comprehensive planning and integrated management in this natural open system, which is necessary to be prioritized in national and regional plans to achieve the sustainable development goals, flood risk and crisis management, and solving water ...
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Problems of watersheds and their water resources require comprehensive planning and integrated management in this natural open system, which is necessary to be prioritized in national and regional plans to achieve the sustainable development goals, flood risk and crisis management, and solving water shortage issues. Purpose of this research is the evaluating and analyses of hydrogeomorphometric components in Bastam watershed systematically to understand environmental, flood and erosion issues. In this regard, parameters of the height distribution, average height, altimetry and hypsometry curves, slope, aspect, watercourse rating, branching ratio, drainage density, watercourse boundary, main watercourse length, concentration time, perimeter, area, basin shape, Gravilius coefficient and equivalent rectangle was evaluated. Results showed that study basin with an average height of 2085.341 meters and an average slope of 21.788% is a mature and relatively smooth basin, and its upstream slopes at altitudes of more than 2100 meters are exposed to exploration due to the roughness youth. Maximum extent of the basin with 24.53% belongs to the southeast aspect. Shape of the basin is like a rectangle with a length of 91.842 km and a width of 19.175 km, which has a medium to small flood capacity. Components of branching ratio 3.528, drainage density 0.2985 and compression coefficient 0.09352 indicate the low to moderate flooding of this basin. Its concentration time in the main waterway with a length of 62.675 km is equal to 6.066 hours, which has the maximum flood with 6-hour rains.
پژوهشی
Hydrology
Raoof Mostafazadeh; Javanshir Azizi Mobaser; Shahnaz Mirzaei
Abstract
The river flow regime can be influenced by various climatic and anthropogenic factors, including land use changes, dam construction, flow diversion, and water abstraction, leading to changes in available water and environmental flow allocation patterns. This study compares the changes in flow regime ...
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The river flow regime can be influenced by various climatic and anthropogenic factors, including land use changes, dam construction, flow diversion, and water abstraction, leading to changes in available water and environmental flow allocation patterns. This study compares the changes in flow regime components between two rivers, one natural and one regulated by a dam, in Ardabil Province. Using R programming, various charts, change point analysis, and significant temporal trends were derived for flow statistics, including high flow, low flow, and baseflow. The results indicate change points in all three flow components (annual maximum, Q10, Q25, low flow, and baseflow) in both natural and regulated rivers, with more pronounced changes occurring in the regulated river after dam construction. In the natural Khiavchai River, high flow and peak discharge showed no significant trends, whereas in the regulated Balikhlochai River, all flow components exhibited significant decreasing trends. Comparison of flow duration curves and violin plots revealed substantial reductions in minimum flows and baseflows in the regulated river, with monthly discharge distributions strongly influenced by dam regulation. Comprehensive evaluation of river regime changes and flow components enables prediction of trends and effective water management for environmental flow allocation.
پژوهشی
watershed
Ali Parvish; Hirad Abghari
Abstract
Watershed management, regardless of the role of local and state operators, will derail water and soil conservation policies and have many negative impacts and consequences in the long term. One of the water supply sources of Lake Urmia is the Baranduzchay River basin. Due to the increasing consumption ...
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Watershed management, regardless of the role of local and state operators, will derail water and soil conservation policies and have many negative impacts and consequences in the long term. One of the water supply sources of Lake Urmia is the Baranduzchay River basin. Due to the increasing consumption behavior of the population, sand mining and exploitation of this river is increasing day by day. Due to the need and importance of flood management and flood control to prevent social and economic problems, this research was carried out with the aim of studying the effects of non-standard sand mining on the hydraulic discharge of the river. The study area is located in the Baranduzchay River in West Azerbaijan Province, Urmia County. In this research, a section of the river from the geographic coordinates 490675 UTM and 4121955 UTM (upstream) to the geographic coordinates 490995 UTM and 4125550 UTM (downstream) is examined. In this research, topographic information is used before harvesting the riverbed and riverbank materials and the triangular irregular network (TIN) is extracted to verify the elevation features using the HEC-GeoRAS plugin, which is a bridge between the hydraulic model of HEC- RAS and ArcGIS: The effects of excessive sand mining on the hydraulic and hydrological properties of the river were studied. According to the research objective, the effects of extracting 1 to 2 meters of hydraulic runoff were simulated. This research showed that when the depth of the river bed increases by one to two meters, the cross section
پژوهشی
Hydrogeomorphology
Khabat Amani; Mossa Hosseini; Mojtabi Yamani; Mehran Maghsoudi
Abstract
There are various methods for determining flood-prone areas, including hydraulic and geomorphological approaches. Due to the extensive nature of flood-prone watersheds, 1:1000 scale maps are either not available in all regions or require significant time and resources to produce. This study aims to identify ...
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There are various methods for determining flood-prone areas, including hydraulic and geomorphological approaches. Due to the extensive nature of flood-prone watersheds, 1:1000 scale maps are either not available in all regions or require significant time and resources to produce. This study aims to identify optimal methods for determining flood-prone areas in regions lacking topographic data. It examines three separate 25-kilometer segments of the Sefidrud River: Yasavol in Kurdistan Province, Gilvan in Zanjan Province, and Astaneh in Gilan Province, using hydraulic and geomorphological approaches. The hydraulic method was implemented using a 1:1000 scale topographic map and two freely available remote sensing DEMs: SRTM (30 meters) and ALOS PALSAR (12.5 meters) in the HEC-RAS . The geomorphological identification of flood-prone areas was conducted based on aerial photographs, both old and new satellite images, field visits, and evidence of past flooding. The results indicate that in mountainous areas, in the absence of high-resolution spatial data, the use of 30-meter SRTM and 12.5-meter ALOS PALSAR DEMs provides acceptable accuracy for delineating flood-prone areas, provided that modeling results are refined and adjusted based on expert opinions and field observations. The comparison of the 30-meter SRTM and 12.5-meter ALOS PALSAR DEMs indicates that in mountainous and hilly areas, both DEMs yield relatively similar results. However, the 30-meter SRTM DEM, particularly in mid-term and long-term return periods, produces more favorable outcomes. In flat and lowland areas, remote sensing DEMs do not provide satisfactory results, and the use of geomorphological methods for delineating flood-prone areas yields higher accuracy
پژوهشی
Hydrogeomorphology
Mehdi Asadi
Abstract
In this study, the ALARM method (Analytical Land Atmosphere Radiometer Model) and UKESM1-0-LL, INM-CM5-0, CanESM5, BCC-ESM1, and ACCESS-CM2 models from the CMIP6 report and SSP scenarios (SSP1.2.6, SSP3.7.0, and SSP5.8.5 scenarios) were used to predict the amount of evapotranspiration in the Ahar Chay ...
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In this study, the ALARM method (Analytical Land Atmosphere Radiometer Model) and UKESM1-0-LL, INM-CM5-0, CanESM5, BCC-ESM1, and ACCESS-CM2 models from the CMIP6 report and SSP scenarios (SSP1.2.6, SSP3.7.0, and SSP5.8.5 scenarios) were used to predict the amount of evapotranspiration in the Ahar Chay watershed. The results of the ALARM method were also compared with the FAO Penman-Monteith and Torrent-White methods. For this purpose, 72 Landsat 8 OLI sensor images related to row 168 and pass 33 were used. The results showed that the ALARM method had the highest correlation (R^20.915) and the lowest error (RMSE 1.493 and MSE 1.232 mm) with the Penman-Monteith method. The RMSE and MSE values for evapotranspiration in all the models studied were below 2.867, and the lowest RMSE and MSE values were for the ACCESS-CM2 model with numerical values of 0.198 and 0.165, respectively, in the SSP1.2.6 scenario. It is also worth noting that the models studied did not perform very well in evaluating the evapotranspiration parameter in the SSP5.8.5 scenario, and the RMSE and MSE values in all models were above 1. This value in SSP5.8.5 in the UKESM1-0-LL model has the highest evapotranspiration rates with numerical values of 2.867 and 2.735, respectively. Also, the amount of very high soil salinity, based on the NDSI and S indices, has increased by about 6,613.81 and 6,296.81 hectares, respectively, from 2013 to 2024, which has a correlation of 0.987 with the increasing trend of evaporation and transpiration in climate scenarios.
پژوهشی
Geomorphology
Mousa Abedini; Mahrokh sardashti
Abstract
In recent years, the Kandovan-Chalus axis in the north of the country (in Mazandaran province) has experienced numerous dangerous floods. Geological and topographic features, precipitation and human intervention have made the Kandovan-Chalus axis susceptible to potential flood risks. In addition to natural ...
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In recent years, the Kandovan-Chalus axis in the north of the country (in Mazandaran province) has experienced numerous dangerous floods. Geological and topographic features, precipitation and human intervention have made the Kandovan-Chalus axis susceptible to potential flood risks. In addition to natural factors; lack of dredging, lack of proper watershed management and unprincipled human interventions have led to an increase in flood risks in the researched area. The aim of this research is to zone flood-prone areas and determine the priority of factors affecting their occurrence using the random forest algorithm in the Kandovan-Chalus axis. For this purpose, 9 land use indicators were selected: distance from the river, slope, height, failure to observe the river boundary, river discharge, waterway network, rainfall, and lack of river dredging. After determining the variance inflation factor and tolerance coefficient, in the next stage, modeling was carried out by entering the data related to the effective factors into the ARC/MAP10.2 software. Then, the random forest algorithm was used to determine the role of the effective factors in the occurrence of floods in the region. Finally, a flood risk zoning map was prepared in three very dangerous, medium-risk, and low-risk zones in the ARC/MAP10.2 environment. The results show that based on the flood potential map, the risk of flooding in the region is about 261.43 square kilometers of the region, 151.1 square kilometers of the region are considered low-risk areas, 118.3 square kilometers of the region are considered medium-risk areas, and about 118.3 square kilometers
پژوهشی
Geomorphology
بهناز سلیمانی; maryam ilanloo
Abstract
Understanding the river's changes and displacements in the past decades is essential for future planning. Using remote sensing facilities, satellite images, and aerial photographs, these goals can be achieved at minimal cost and in the shortest possible time. The aim of this study is to zone the ...
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Understanding the river's changes and displacements in the past decades is essential for future planning. Using remote sensing facilities, satellite images, and aerial photographs, these goals can be achieved at minimal cost and in the shortest possible time. The aim of this study is to zone the temporal and spatial changes of the riverbed using satellite images in the Arc/Map software environment. Landsat satellite images from 1973, 1986, 1999, 2012, and 2024 were used to examine and monitor the temporal and spatial changes of the Bahmanshir River. The river was divided into six different intervals and the changes were zoned in seven classes: high sedimentation, medium sedimentation, low sedimentation, stable, low erosion, medium erosion, and high erosion. The results showed that in all periods except the 1999-2012 period, the sedimentation rate prevailed over the erosion rate. In all periods except the 1999-2012 period, the sedimentation rate prevailed over the erosion rate. The largest changes occurred in the first period during the period 1999-2012, in the second, fourth and fifth periods during the period 1973-1986, and in the third and fifth periods during the period 2012-2024. Considering that in all the periods studied except the period 1999-2012, sedimentation prevailed over erosion, only in the first period did erosion exceed sedimentation.
پژوهشی
Hydrogeomorphology
Rouhollah Nadri; Hasan Alizadeh
Abstract
This research was conducted with the aim of investigating the geological and structural condition of Kopeh Dagh structural zone to create the karst phenomenon. Using the digitization of geological maps, the main faults of the studied area were identified. The condition of limestone formations, length, ...
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This research was conducted with the aim of investigating the geological and structural condition of Kopeh Dagh structural zone to create the karst phenomenon. Using the digitization of geological maps, the main faults of the studied area were identified. The condition of limestone formations, length, number and density of faults and fractures were investigated. Due to the existence of many fractures in the area and the complexity of their analysis, the fractal dimension analysis method was used to prepare the fracture density map.The results showed that there is a very close relationship between the number of springs and the distance from faults, such that the largest number of springs studied are located near fault lines, but the spring discharge rate has no relationship with the distance from the fault and is more related to geological formations. Parts of the studied structural zone that have the highest density of faults and fractures in thick-bedded carbonate formations have the highest potential for karst groundwater in the region. In the structural zone of Kopeh Dagh, Mozduran and Tirgan basins have the most underground water reserves, followed by the Dareh Gaz, Quchan, Kardeh, and Quzaghan Chai basins, respectively.Therefore, this study can be an introduction to obtaining new water sources in the region.
پژوهشی
Hydrogeomorphology
LiLi Asle Mohamadi; Abdloah Behboodi; Fariba Karami
Abstract
The settlement of human societies on the Earth's surface has consistently aimed to maximize access to natural resources, such as water resources, suitable vegetation cover, and arable land. Undoubtedly, this endeavor is based on principles now understood as the science of spatial planning. The primary ...
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The settlement of human societies on the Earth's surface has consistently aimed to maximize access to natural resources, such as water resources, suitable vegetation cover, and arable land. Undoubtedly, this endeavor is based on principles now understood as the science of spatial planning. The primary objective of this research is to examine the role of environmental factors in the settlement patterns of archaeological mounds in Maragheh County using the MACBETH and SWARA models. To achieve this goal, variables including topography (slope, slope direction, elevation classes), hydrology (distance from rivers, aqueducts, and springs), lithology, soil, and land use were analyzed.
According to the results, elevation classes, distance from rivers, and slope have the most significant influence on the distribution patterns of the archaeological mounds, while the distance from aqueducts plays the least role. Validation results showed that in the SWARA model, 51, 19, and 7 of Maragheh’s archaeological mounds fall into highly suitable, suitable, and other zones, respectively. In contrast, the MACBETH model places 35, 20, and 22 of these mounds in highly suitable, suitable, and other zones.
Thus, it can be concluded that the SWARA model demonstrates superior performance compared to the MACBETH model for this region.
پژوهشی
Geomorphology
farhad khodamoradi; Shahram Roostaei; Ali Zareiyan
Abstract
Landslides are influenced by internal, external (climatic), and anthropogenic factors. Salavatabad Pass, located in eastern Sanandaj along the Sanandaj–Hamedan route, is a highly vulnerable area experiencing recurrent landslides. The presence of the main road, along with uncontrolled construction, ...
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Landslides are influenced by internal, external (climatic), and anthropogenic factors. Salavatabad Pass, located in eastern Sanandaj along the Sanandaj–Hamedan route, is a highly vulnerable area experiencing recurrent landslides. The presence of the main road, along with uncontrolled construction, gardening, and road construction, has exacerbated these hazards. This study aims to identify, quantify, and classify continuous slope movements using radar interferometry and land use analysis. To assess vegetation cover, the NDVI index was derived from eight Sentinel-2 images, aiding in the selection of appropriate radar imagery. Additionally, four Sentinel-1 images from 2020 to 2023 were processed in SNAP software to analyze surface displacements. The land use map was generated using a 2023 Landsat-8 image, with supervised classification applied in ArcGIS, categorizing the area into six classes. The results indicate an annual displacement of 2.4 cm, totaling 9.5 cm over the study period. Hazard zoning revealed that 14.45% of the area falls within the high-risk category, while 29.33% is classified as moderate risk. The road network was divided into three segments, with the first (6.59 km) and second (6.6 km) segments classified as high and moderate risk, respectively. Ultimately, 18 unstable zones were identified along the road, with 16 primarily associated with rangeland and barren land use. The highest displacements were observed on slopes with northern, northwestern, southern, and western aspects..
پژوهشی
Geomorphology
Mohamad Sharifi Paichoon; Leila Moosavi
Abstract
Flooding, while a natural phenomenon that contributes to the formation of fertile plains and agricultural terraces is now recognized as one of the most significant natural disasters globally. This research examines the key factors influencing flooding, assessing their significance and impact across different ...
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Flooding, while a natural phenomenon that contributes to the formation of fertile plains and agricultural terraces is now recognized as one of the most significant natural disasters globally. This research examines the key factors influencing flooding, assessing their significance and impact across different areas of the Hor Roud catchment. Initially, critical indicators such as precipitation, soil, lithology, land use, drainage networks, elevation, slope, and slope direction were identified, mapped, and organized into information layers. These layers were converted into raster format and reclassified. To refine the data, a fuzzy logic approach was applied, utilizing linear and triangular functions based on the properties and effects of each layer. The fuzzy layers were then combined using gamma (0.9) operators. Additionally, the TOPSIS technique was employed to pinpoint the most influential indicators within the basin’s spatial zones. The final results, obtained from a fuzzy logic map and a TOPSIS technique, indicated that distant to the main stream, lithology, and land use were the most influential factors contributing to flooding in the Hor Roud catchment. The maximum flooding occurs along the banks of the main rivers, where conglomerate, marl, and clay soils cultivated. The flood risk map identified key contributing factors: slopes between 0-10%,, elevations of 1500-1800 meters, hydrological group D soils, cultivated land, conglomerate rock formations, proximity to main streams , and annual precipitation levels between 800-800 millimeters. The findings revealed that distant to the main stream, lithology, and land use were the most significant factors driving flooding in the Hor Roud catchment.
پژوهشی
Geomorphology
Leila Aghayari; sayyad Asghari Saraskanroud; Batool Zeinali
Abstract
The aim of the present study is to investigate the changes in different land uses and evaluate the effects of land use changes on soil erosion in Namin County. In order to achieve the goals of this study, first a land use map was prepared using the object-oriented method for the two periods of 2002 and ...
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The aim of the present study is to investigate the changes in different land uses and evaluate the effects of land use changes on soil erosion in Namin County. In order to achieve the goals of this study, first a land use map was prepared using the object-oriented method for the two periods of 2002 and 2024. In the next stage, information layers of other effective factors for soil erosion of the city were prepared in the GIS environment. The evaluation and standardization of the layers were carried out using the fuzzy membership function and weighting of the criteria, using the CRITIC method. The final analysis and modeling was carried out using the ARAS multi-criteria algorithm. The results of this study showed that the largest area in 2002 was related to poor pastures and rainfed agriculture, with 493.71 and 209.91 square kilometers, respectively, and in 2024, it was related to poor pastures and rainfed pastures with 422.62 and 271.93 square kilometers, respectively. According to the 2002 erosion zoning map, 15.05 and 22.46 percent, respectively, and according to the 2024 erosion zoning, 15.92 and 25.04 percent of the county's area are in the two very high-risk and high-risk categories, respectively. In general, the presence of erodible soil, the occurrence of heavy rainfall, and the intervention of human factors through land use change, destruction of vegetation, excessive grazing, road construction, plowing on slopes, and improper irrigation can be considered as the major factors of soil erosion and reduced fertility in Namin City.
