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
Hydrogeomorphology
Mohammad Hossein Rezaei Moghaddam; Davoud Mokhtari; meysam skandarialni
Abstract
Hydrological models are an effective tool for managing water resources as well as water balance components among research works. Today, basin hydrological models have been developed, but choosing the right model to simulate a specific basin has always been a challenge. Therefore, it is necessary to choose ...
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Hydrological models are an effective tool for managing water resources as well as water balance components among research works. Today, basin hydrological models have been developed, but choosing the right model to simulate a specific basin has always been a challenge. Therefore, it is necessary to choose a model that can simulate the hydrological processes with the simplicity of the structure and using minimal factors. Northwest Iran was simulated by AWBM and SWAT models. The AWBM model is an integrated model that simulates the runoff in catchment areas using two variables, rainfall and evaporation, and on the other hand, the SWAT model is a continuous and semi-distributed model that simulates hydrological processes using the physical characteristics of the basin (soil, land use, slope) as well as several water and meteorological information such as rainfall, temperature. The results of runoff simulation in the calibration and validation periods were evaluated using two Nash Sutcliffe statistical indices (NSE) and R2 coefficient of determination. By comparing the results of the statistical indicators used in the study, it was found that the SWAT model has better results in the simulation of monthly runoff in the validation and validation periods.
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
Groundwater
imad ali; maryam bayati khatibi; sadra karimzadeh
Abstract
This study aimed to delineate groundwater recharge zones using a combination of analytical hierarchy process (AHP), fuzzy-AHP, and frequency ratio (FR) models. Additionally, it aimed to compare the effectiveness of these models in groundwater recharge potential zone mapping. To achieve these objectives, ...
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This study aimed to delineate groundwater recharge zones using a combination of analytical hierarchy process (AHP), fuzzy-AHP, and frequency ratio (FR) models. Additionally, it aimed to compare the effectiveness of these models in groundwater recharge potential zone mapping. To achieve these objectives, nine groundwater influencing factors were considered, including geology, soil types, lineament density, elevation, slope, topographic wetness index, drainage density, land use land cover, and rainfall. Thematic maps for all these factors were generated using satellite and conventional data in the ArcGIS environment. Weight was assigned to each thematic layer based on its significance to recharge. All thematic layers were combined using AHP model-l (WLC), AHP model-ll (Weighted sum), fuzzy-AHP overlay, and FR-based model using ArcGIS. The findings revealed that 15% and 39% of the study area have high recharge potentials according to AHP-based model-l and model-ll, respectively. The FAHP model demarcated 43% of the area as high recharge zones while the FR model demarcated 42% of the area as high recharge zones. The majority of high groundwater recharge areas were found in the central part of the study area, while the southern part was demarcated as a moderate recharge zone. The eastern and western parts were demarcated as low recharge potentials zones. To validate the accuracy of these models, the study used receiver operating characteristic (ROC) validation curves. The ROC curves revealed that AHP model-ll had the highest accuracy (AUC=89%) followed by the FAHP model (AUC=88%), AHP model-l (AUC=84%), and FR (AUC=81%)
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
Geomorphology
Fariba Esfandyari Darabad; Ghobad Rostami; Raoof Mostafazadeh; Mousa Abedini
Abstract
In the current study, the risk of landslides in the Zamkan Watershed, located in Kermanshah Province, was evaluated. Two machine learning models, Support Vector Machine (SVM), and Logistic Regression, were used to prepare a landslide susceptibility map. Toward this, 13 informational layers including ...
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In the current study, the risk of landslides in the Zamkan Watershed, located in Kermanshah Province, was evaluated. Two machine learning models, Support Vector Machine (SVM), and Logistic Regression, were used to prepare a landslide susceptibility map. Toward this, 13 informational layers including elevation, slope, aspect, Melton ruggedness number, terrain convexity, stream length, valley depth, topographic wetness index, precipitation, geological formations, distance from rivers, distance from roads, and vegetation cover were utilized as independent variables. Approximately 70% of the watershed's landslide pixels were used for model training, and 30% for model validation. Model validation was performed using ROC curves. The results indicated the higher performance and accuracy of the radial basis function (RBF) kernel of the SVM model for generating landslide hazard maps in the study area. The area under the curve (AUC) for the RBF kernel was approximately 0.951 for model training and 0.944 for model testing. The results suggest that slope with a coefficient of 0.28, precipitation with a coefficient of 0.27, lithology with a coefficient of 0.26, and elevation with a coefficient of 0.22 are the main controlling factors for landslides occurrence in the Zamkan Watershed. Both the SVM model and logistic regression confirmed the deterministic effects of selected factors on landslides. About 35% of the study area as classified as highly susceptible to landslides, primarily in the eastern half of the watershed. Factors such as high elevation, steep slopes, heavy precipitation, and the Kazhdomi Formation's composition were identified as key contributors to this susceptibility.
پژوهشی
watershed
Sepideh siyooti; Alireza Ildoromi; Behnoosh Farrokhzadeh
Abstract
In this research, the flood-blocking nodes of the drainage network in Khako (Faqira-Khidr) urban basin of Hamedan were measured and evaluated using the SWMM model. The results showed that the infiltration and runoff height of the project in the SCS method are equal to 50.86 and 16.14 mm, respectively, ...
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In this research, the flood-blocking nodes of the drainage network in Khako (Faqira-Khidr) urban basin of Hamedan were measured and evaluated using the SWMM model. The results showed that the infiltration and runoff height of the project in the SCS method are equal to 50.86 and 16.14 mm, respectively, and this indicates that the SCS method is a more accurate assessment of the infiltration and runoff values for the Hamadan urban watershed. and has an acceptable efficiency. The results show that out of the total rainfall of 120 mm, 33 mm is related to infiltration losses and 87 mm is related to surface runoff, and the flow volume is equal to 2.41 million cubic meters, which is 1.98 1 million cubic meters is related to Faqireh sub-basin and 0.43 million cubic meters is related to Khizr sub-basin. According to the efficiency coefficient of NS, which is calculated as 0.66 for the peak discharge and 0.73 for the flood volume, and these numbers are acceptable. The results showed that the highest volume of rainfall runoff of the project with 1.28 million cubic meters is related to Faqirah sub-basin due to the physical development of Hamedan city in recent years in this sub-basin and the lowest amount with 0.46 million cubic meters is related to the sub-basin. It is Khedrkhako. The results of this research showed that residential uses have the largest share in the flood potential of the study area.
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.
پژوهشی
Geomorphology
maryam bayatikhatibi; maryam bayati khatibi; imad ali; sadra kharimzadeh
Abstract
The Quetta sub-basin is a part of the Pishin River basin, situated in the southwestern region of Pakistan. This study aimed to determine the spatial distribution of annual soil erosion through the utilization of the Revised Universal Soil Loss Equation (RUSLE) model. To accomplish this, numerous data ...
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The Quetta sub-basin is a part of the Pishin River basin, situated in the southwestern region of Pakistan. This study aimed to determine the spatial distribution of annual soil erosion through the utilization of the Revised Universal Soil Loss Equation (RUSLE) model. To accomplish this, numerous data mining techniques were employed, along with machine learning algorithms, to produce thematic layers (K, R, LS, C, and P) that served as input parameters for the RUSLE model. According to the resultant model, soil erosion in the study area ranged from 0.00 to 866 tons per hectare per year. The estimated values for rainfall-runoff erosivity (R), soil. erodibility (K), topography (LS), and cover management (C), factors ranged from 147 to 191 (MJ.mm.ha⁻¹.h⁻¹year⁻¹), 0.0229 to 0.0259 (t.ha.MJ⁻¹mm⁻¹), 0.002 to 360.77, and 0.001 to 1, respectively. The statistics revealed that 58% of the land in the study area experiences a very low degree of soil erosion, at an erosion rate less than 13.58 t/ha/year. About 24% of the study area faces low erosion, with an erosion rate spanning from 13.58-44.16 t/ha/year. 13% of the area is demarcated as moderate soil erosion severity, at an erosion rate ranging from 44.16-81.53.14 t/ha/year. On the other hand, 5% of the study area experienced high to very high soil erosion, with an erosion rate of 81.53-866.34 t/ha/year.
پژوهشی
Hydrogeomorphology
Abazar Esmali Ouri; Shokrollah Asghari; Arezoo Eshaghzadeh; Raoof Mostafazadeh
Abstract
Determining the extent of riverbank erosion and displaying it as a map in a GIS environment is effective in the optimal management of water and soil resources. The aim of the current research is to delineate the riverbank erosion zone from aerial photographs, perform regression modeling, and identify ...
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Determining the extent of riverbank erosion and displaying it as a map in a GIS environment is effective in the optimal management of water and soil resources. The aim of the current research is to delineate the riverbank erosion zone from aerial photographs, perform regression modeling, and identify factors influencing the development of riverbank erosion using various spatial data including physiographic, hydrological, geological, and environmental data in different sections of the Balikhlouchai River in Ardabil Province. Initially, influential parameters in riverbank erosion in the region, including topographic, soil and land factors, hydrology, and land use changes, were calculated. Accordingly, the variables under study were obtained for four time periods: 1955 using aerial photographs, 1980 using TM satellite images, and years 2010 and 2013 using Google Earth images, and the effective extent of riverbank erosion was compared. Subsequently, multivariate regression analysis was performed using independent variables (including topographic, hydrological, soil erodibility, and land factors) and the effective extent of riverbank erosion as the dependent variable, using SPSS software, and suitable models were developed to estimate the amount of different riverbank erosion. Based on the results of regression analysis, environmental parameters such as slope of the river reaches, peak discharge, area under irrigated agriculture, concentration time, pasture coverage, and residential areas played a more significant role in exacerbating riverbank erosion.
پژوهشی
Geomorphology
Gholam hassan jafari; zinab barati
Abstract
The analysis of some geological features and structures can be used to determine Quaternary developments. Analyzing the types of landslides, their density, and scale is the key to identify the evolution of landforms. Based on this, the current research was carried out with the aim of spatial analysis ...
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The analysis of some geological features and structures can be used to determine Quaternary developments. Analyzing the types of landslides, their density, and scale is the key to identify the evolution of landforms. Based on this, the current research was carried out with the aim of spatial analysis of landslides that occurred in different lithologies of Mo’alem-Kelayeh basin, a part of eastern Alamut basin, between the longitudes 50°26'00″ to 50°31'20″ and the latitude 36°22'00″ to 36°30'00″, based on topographical, geological conditions, vegetation, the condition of waterways, and the proximity of different rocks in the area. According to the results, the Karaj, Rute, Shamshek and Neogene and destructive sediments are the most erodible formations in the studied area, which are the most important factors involved in the occurrence of mass movements on a micro and macro scale under the Mo’alem-Kelayeh basin. The nonresistant lithology is more extensive in the geographical levels downstream of the rivers. In such areas, in addition to the loosening of the lithology in wide sections, the material and energy flowing in the river also increases, if due to the lower slope of the slopes, the effect of the river on movements of the slopes becomes more limited. In the terrestrial levels close to the ridge line, matter and energy are less and lithology is more resistant; But due to greater slope of the slopes and the involvement of physical weathering in the porosity of rocks, the effect of river on the occurrence of surface slope movements increases.
پژوهشی
Hydrogeomorphology
Hamid Amoonia; Mohammadreza Yousefi Roshan; Mohammad Dِaymevar
Abstract
Gorgan Bay, one of the most important wetlands in northern Iran, has experienced significant water level fluctuations with severe environmental consequences for surrounding areas. This study employs a comparative analysis of spectral water indices to monitor water level changes in Gorgan Bay. Previous ...
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Gorgan Bay, one of the most important wetlands in northern Iran, has experienced significant water level fluctuations with severe environmental consequences for surrounding areas. This study employs a comparative analysis of spectral water indices to monitor water level changes in Gorgan Bay. Previous studies have documented substantial water level variations, leading to substantial ecological and economic losses, highlighting the urgent need for effective management strategies. The present research utilizes Landsat 5 and 8 images to investigate water level changes in Gorgan Bay through a comparative assessment of spectral water indices (NDWI, MNDWI, AWEI, and NDPI). The findings reveal that MNDWI outperforms other indices, with an average RMSE of 21/66, for water extraction from Landsat imagery. MNDWI-derived water area estimates indicate an increase of 2384 hectares between 1990 and 2000, a decrease of 1488 hectares between 2000 and 2010, and a further decrease of 11080 hectares between 2010 and 2020. The alarming 11080-hectare decline in water area from 2010 to 2020 underscores the need for intensified efforts in Gorgan Bay's water level monitoring and management. This study emphasizes the potential of satellite imagery and spectral water indices, particularly MNDWI, as valuable tools for effective water level monitoring and management in Gorgan Bay. The results can serve as a scientific guide for managing and planning water level changes in Gorgan Bay.
پژوهشی
Geomorphology
Reza esmaili; Niusha Nourizadeh Nesheli
Abstract
Rivers are natural systems that have undergone significant changes in their morphology due to human pressures over the past decades. The factors influencing river morphological changes and their responses vary across different regions. Consequently, in the present study, morphological changes in a section ...
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Rivers are natural systems that have undergone significant changes in their morphology due to human pressures over the past decades. The factors influencing river morphological changes and their responses vary across different regions. Consequently, in the present study, morphological changes in a section of the Haraz River in of Amol city were investigated over a 53-year period (from 1968 to 2021).The changes in river width, planform, and riverbed landforms were examined using aerial photographs and satellite imagery. Subsequently, by calculating the specific stream power and conducting field observations, the hazards associated with the river channel were identified. In 1968, the average river width was measured at 141 meters, but by the years 2006 and 2021, it had decreased to 55 meters. The area of riverbed landforms, including the active riverbed and longitudinal bars, decreased by 50% and 95%, respectively, during this period. The river channel transitioned from a braided pattern to a single-channel pattern due to channel narrowing and significant reduction in longitudinal bars. These changes led to an increase in stream power and erosional processes, resulting in river incision and bank erosion. Key factors contributing to the morphological alterations in the study area included the reduction in base flow, irrigation channel diversion, and land use changes along the river margins. Considering the observed trends, the construction of a new dam (Haraz Dam), continued exploitation of floodplain areas, and channelization could exacerbate the risks associated with the river channel and lead to significant floods.
پژوهشی
Geomorphology
sayyad Asghari Saraskanroud; Fariba Esfandyari; Mehdi Faal Naziri; Batool Zeinali
Abstract
Land subsidence refers to the gradual or sudden lowering of the earth's surface as a result of various factors such as tectonic activities, mining, oil and gas fields, and illegal extraction of underground water. In Alborz province, the growing trend of population and migration in recent years has ...
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Land subsidence refers to the gradual or sudden lowering of the earth's surface as a result of various factors such as tectonic activities, mining, oil and gas fields, and illegal extraction of underground water. In Alborz province, the growing trend of population and migration in recent years has added to the increase in demand and the amount of water withdrawal from the underground water table, so it is subject to subsidence due to the sharp drop in the level of underground water. In this research, subsidence assessment was done using radar interferometric technique, and then, prone areas were zoned with multi-criteria algorithm in the time frame of 2016 and 2023. The results of information extraction with interferometric technique showed that the average amount of subsidence in the urban boundaries of Saujblag, Karaj, Nazarabad, Chaharbagh and Fardis is between 15 and 320 mm. According to observations, the highest amount of subsidence is in the eastern part and then in the southern and southwestern parts. According to the estimated results of subsidence risk zoning; The parameters of water level drop, land use, slope and geology, respectively, with weight coefficients of 0.16127, 0.141875, 0.130145 and 0.128474, are the most important factors in creating the risk of subsidence in the study area, which are 31 and 23%, respectively. From the range, it has a very high and high probability of danger.
پژوهشی
Geomorphology
Shahram Bahrami; Arezou Cheraghi; Somayeh Khaleghi; Kazem Nosrati
Abstract
Dolines are one of the most important karst landforms and play an important role in soil formation. In this study, the morphometry of dolines and their relationship with the physicochemical characteristics of soil in Noakoh anticline were evaluated. Chemical and physical characteristics of 36 soil samples ...
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Dolines are one of the most important karst landforms and play an important role in soil formation. In this study, the morphometry of dolines and their relationship with the physicochemical characteristics of soil in Noakoh anticline were evaluated. Chemical and physical characteristics of 36 soil samples of dolines were collected and measured in the laboratory. Also, digital elevation model (DEM; 13 cm cell size) obtaining from UAV images, was used to measure the morphometric parameters of dolines. The results showed that large dolines have higher slope, depth and roundness, as well as sandy soils, and higher EC, pH, potassium, phosphorus, water holding capacity and soil organic carbon. Also, low- elevation dolines have large area, slope, depth, roundness and clay soils, and higher EC, PH, potassium, water holding capacity, organic carbon, and saturation percentage than high elevation dolines. The dolines located in the plunge of the anticline have large area, slope, depth, roundness and clay soils, as well as more EC, PH, potassium, water holding capacity, organic carbon and saturation percentage than the dolines in the central part. The mean of the most morphometric parameters and physicochemical characteristics of the soil in high-slope dolines is higher than in low-slope dolines. Therefore, the morphometric and pedological differences of dolines show that their formation and evolution are more at lower altitudes, plunge and steep slopes. In general, vegetation, elevation, slope and type of precipitation play an important role in morphometric differences and soils in dolines.
