University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 01 The Role of Land Use Changes in Shaping Surface Temperature in Cities: A Case Study of Isfahan" The Role of Land Use Changes in Shaping Surface Temperature in Cities: A Case Study of Isfahan" 1 17 94121 10.22059/jphgr.2023.361681.1007779 FA Zohreh Rooki Department of Natural Geography, Faculty of Geography, University of Tehran, Tehran, Iran H Mohammadi Department of Natural Geography, Faculty of Geography, University of Tehran, Tehran, Iran Rahman Zandi Department of Natural Geography, Faculty of Geographical Sciences and Planning, Isfahan University, Isfahan, Iran 0000-0002-1531-8260 Journal Article 2023 05 22 <strong>ABSTRACT</strong> The expansion and development of cities and the increase of urbanization are some of the current characteristics of human societies, especially in developing countries. Density and population growth in cities have led to the expansion and development of urban areas and changes in urban land use. In this research, a remote sensing technique was used to identify the patterns and examine the spatial changes in the surface temperature in different areas of Isfahan City. Using thermal equations and a similarity centre algorithm, the temperature of the earth's surface has been calculated for the periods of 1365 to 1401. The supervised classification of the most similar method was used to evaluate the changes in the land use of the studied area, which includes built uses, gardens, vegetation, and lands without vegetation. The results of the comparison of land use between 1365 and 1401 within the scope of studies show that during the mentioned period residential use increased by 175.94 square kilometers and garden use by 74.28 km shows a decreasing trend. Also, we see a decrease of 39.03 km in the use of vegetation and a decrease of 217.75 km in the use of areas without vegetation. The results of the earth surface temperature survey show the expansion of the earth surface temperature during the study period in Isfahan city. Based on this, in the studied period, the earth's surface temperature increased in the east and southeast regions. Examining the isothermal lines shows that the temperature of the earth's surface around the city increased significantly in terms of temperature and extent <strong>Extended abstract</strong> <strong>Introduction</strong> Howard first coined the term thermal island about a century ago, in 1833. Subsequently, numerous studies were conducted in major cities and industries around the world to find that urbanization caused significant changes. Consideration has been given to meteorological parameters and ground surface features, and consequently, many changes have been made in the local climate. Studies show that the role of thermoelectric sensing is crucial for studying the effects of thermal islands. Thermal remote sensing data have provided the opportunity to dynamically monitor and evaluate urban heat islands. Thermal remote sensing data is a unique source for defining the surface thermal island associated with the urban canopy thermal island. Synoptic meteorological station data have high temporal resolution and long-term overlap. Thermal remote sensing can provide an overview of each city and is particularly important for accurate city-level climate monitoring. Isfahan is at 51 degrees 39 minutes 40 seconds east longitude and 32 degrees 38 minutes 30 seconds north latitude. It is situated in a sedimentary plain that extends to relatively wide plains. Isfahan city covers an area of 106,786 square kilometers. Isfahan Province is one of the central provinces of Iran, with Isfahan city as its capital. The province ranks sixth in terms of area and third in population among all provinces in Iran and holds the first position in terms of urbanization in the country.   <strong>Methodology</strong> This study used 7 images of Landsat OLI and EMT sensors and Landsat TM multilingual image. These images cover the period 1986 to 2022 (36 years period); due to the intensity of heat in the summer months, these images are for the summer months and then to reduce and eliminate image errors, a series of preprocessing and geometric and radiometric corrections were applied to the images. The supervised method is then used to classify the information. In this method, training samples were used to classify the pixels. Similarity centers algorithm was used to classify the monitoring. This method analyzes the value of bivariate and each unknown pixel based on the variance and covariance of that spectral reaction class. It assumes that the data distribution for each class is based on the normal distribution around the mean pixel of that class. Finally, the kappa method was used for model validation and classification. Analysis of land use changes in Isfahan County from 1986 to 2022 revealed that in 1986, the majority of land use categories were areas without vegetation cover, covering an area of 338.53 square kilometers (61.51%). The least land use category included water bodies and vegetation cover, with areas of 0.72 square kilometers (0.13%) and 40.90 square kilometers (0.89%), respectively. The built-up land use category was scattered in the northern, eastern, and central parts, covering an area of 73.88 square kilometers (24.02%). Orchards accounted for 132.18 square kilometers, representing 24.02% of the total area. The areas without vegetation cover were concentrated in the southern and southwestern regions, specifically in zones 5, 6, 9, and 13, in the eastern part of zone 15, and in the northern part of zone 12.   <strong>Results and discussion</strong> The study's findings on land use changes in the area from 1986 to 2022 indicate that the built-up area increased from 8.73 square kilometers to 82.249 square kilometers. The vegetation covers also expanded from 9.40 square kilometers to 20.80 square kilometers. However, the area of orchards decreased from 132.01 square kilometers to 90.57 square kilometers. The areas without vegetation cover also decreased from 338.05 square kilometers to 78.120 square kilometers. Finally, the water bodies decreased from 0.72 square kilometers to 0 square kilometers in terms of land use. The examination of the relationship between isotherms (temperature lines) and land use in 1986 revealed that the highest temperature lines were associated with barren lands. Due to a lack of moisture, these lands become extremely hot during the day, leading to temperatures reaching up to 45 degrees Celsius (common in the plains and deserts of this county). Additionally, vegetation cover in the northeastern and northwestern directions acts as a natural modifier and cooler for the city. In this land use category, temperatures reach a minimum of around 30 degrees Celsius. For residential areas, which have experienced the most expansion in urban areas, the average temperature reaches around 40 degrees Celsius. This land use category acts as an intermediate zone among other land uses.   <strong>Conclusion</strong> Investigations show that most articles have focused on land use changes or thermal islands but have not examined the role of land use and its changes on thermal island formation over 36 years. This study used the most modern and scientific remote sensing algorithms, first using Landsat satellite imagery to investigate the relationship between land use changes and surface temperature. Land use and temperature relationships indicate that residential areas have been replaced in urban areas due to population growth, buildings, cement, and asphalt organizations. These surfaces will absorb the sun rather than reflect it, raising the temperature in urban areas and dominating a particular climate. The results also showed that the Zayandeh Rud River and vegetation in the river water area were moderated. <strong> </strong> <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work.   <strong>Conflict of Interest</strong> Authors declared no conflict of interest.   <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. <strong>ABSTRACT</strong> The expansion and development of cities and the increase of urbanization are some of the current characteristics of human societies, especially in developing countries. Density and population growth in cities have led to the expansion and development of urban areas and changes in urban land use. In this research, a remote sensing technique was used to identify the patterns and examine the spatial changes in the surface temperature in different areas of Isfahan City. Using thermal equations and a similarity centre algorithm, the temperature of the earth's surface has been calculated for the periods of 1365 to 1401. The supervised classification of the most similar method was used to evaluate the changes in the land use of the studied area, which includes built uses, gardens, vegetation, and lands without vegetation. The results of the comparison of land use between 1365 and 1401 within the scope of studies show that during the mentioned period residential use increased by 175.94 square kilometers and garden use by 74.28 km shows a decreasing trend. Also, we see a decrease of 39.03 km in the use of vegetation and a decrease of 217.75 km in the use of areas without vegetation. The results of the earth surface temperature survey show the expansion of the earth surface temperature during the study period in Isfahan city. Based on this, in the studied period, the earth's surface temperature increased in the east and southeast regions. Examining the isothermal lines shows that the temperature of the earth's surface around the city increased significantly in terms of temperature and extent <strong>Extended abstract</strong> <strong>Introduction</strong> Howard first coined the term thermal island about a century ago, in 1833. Subsequently, numerous studies were conducted in major cities and industries around the world to find that urbanization caused significant changes. Consideration has been given to meteorological parameters and ground surface features, and consequently, many changes have been made in the local climate. Studies show that the role of thermoelectric sensing is crucial for studying the effects of thermal islands. Thermal remote sensing data have provided the opportunity to dynamically monitor and evaluate urban heat islands. Thermal remote sensing data is a unique source for defining the surface thermal island associated with the urban canopy thermal island. Synoptic meteorological station data have high temporal resolution and long-term overlap. Thermal remote sensing can provide an overview of each city and is particularly important for accurate city-level climate monitoring. Isfahan is at 51 degrees 39 minutes 40 seconds east longitude and 32 degrees 38 minutes 30 seconds north latitude. It is situated in a sedimentary plain that extends to relatively wide plains. Isfahan city covers an area of 106,786 square kilometers. Isfahan Province is one of the central provinces of Iran, with Isfahan city as its capital. The province ranks sixth in terms of area and third in population among all provinces in Iran and holds the first position in terms of urbanization in the country.   <strong>Methodology</strong> This study used 7 images of Landsat OLI and EMT sensors and Landsat TM multilingual image. These images cover the period 1986 to 2022 (36 years period); due to the intensity of heat in the summer months, these images are for the summer months and then to reduce and eliminate image errors, a series of preprocessing and geometric and radiometric corrections were applied to the images. The supervised method is then used to classify the information. In this method, training samples were used to classify the pixels. Similarity centers algorithm was used to classify the monitoring. This method analyzes the value of bivariate and each unknown pixel based on the variance and covariance of that spectral reaction class. It assumes that the data distribution for each class is based on the normal distribution around the mean pixel of that class. Finally, the kappa method was used for model validation and classification. Analysis of land use changes in Isfahan County from 1986 to 2022 revealed that in 1986, the majority of land use categories were areas without vegetation cover, covering an area of 338.53 square kilometers (61.51%). The least land use category included water bodies and vegetation cover, with areas of 0.72 square kilometers (0.13%) and 40.90 square kilometers (0.89%), respectively. The built-up land use category was scattered in the northern, eastern, and central parts, covering an area of 73.88 square kilometers (24.02%). Orchards accounted for 132.18 square kilometers, representing 24.02% of the total area. The areas without vegetation cover were concentrated in the southern and southwestern regions, specifically in zones 5, 6, 9, and 13, in the eastern part of zone 15, and in the northern part of zone 12.   <strong>Results and discussion</strong> The study's findings on land use changes in the area from 1986 to 2022 indicate that the built-up area increased from 8.73 square kilometers to 82.249 square kilometers. The vegetation covers also expanded from 9.40 square kilometers to 20.80 square kilometers. However, the area of orchards decreased from 132.01 square kilometers to 90.57 square kilometers. The areas without vegetation cover also decreased from 338.05 square kilometers to 78.120 square kilometers. Finally, the water bodies decreased from 0.72 square kilometers to 0 square kilometers in terms of land use. The examination of the relationship between isotherms (temperature lines) and land use in 1986 revealed that the highest temperature lines were associated with barren lands. Due to a lack of moisture, these lands become extremely hot during the day, leading to temperatures reaching up to 45 degrees Celsius (common in the plains and deserts of this county). Additionally, vegetation cover in the northeastern and northwestern directions acts as a natural modifier and cooler for the city. In this land use category, temperatures reach a minimum of around 30 degrees Celsius. For residential areas, which have experienced the most expansion in urban areas, the average temperature reaches around 40 degrees Celsius. This land use category acts as an intermediate zone among other land uses.   <strong>Conclusion</strong> Investigations show that most articles have focused on land use changes or thermal islands but have not examined the role of land use and its changes on thermal island formation over 36 years. This study used the most modern and scientific remote sensing algorithms, first using Landsat satellite imagery to investigate the relationship between land use changes and surface temperature. Land use and temperature relationships indicate that residential areas have been replaced in urban areas due to population growth, buildings, cement, and asphalt organizations. These surfaces will absorb the sun rather than reflect it, raising the temperature in urban areas and dominating a particular climate. The results also showed that the Zayandeh Rud River and vegetation in the river water area were moderated. <strong> </strong> <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work.   <strong>Conflict of Interest</strong> Authors declared no conflict of interest.   <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. https://jphgr.ut.ac.ir/article_94121_5d15f2df3a8a7f639a9141da64857ef1.pdf

University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 01 The Impact of Groundwater on the Landslide Occurrence in the Southern Slope of Shah Neshin Mountain The Impact of Groundwater on the Landslide Occurrence in the Southern Slope of Shah Neshin Mountain 19 36 95006 10.22059/jphgr.2023.364630.1007788 FA Ali Rezapoor Department of Natural Geography, Faculty of Literature and Humanities, Razi University, Kermanshah, Iran Iraj Jabbari Department of Natural Geography, Faculty of Literature and Humanities, Razi University, Kermanshah, Iran Kazem Bahrami Department of Natural Geography, Faculty of Literature and Humanities, Razi University, Kermanshah, Iran Journal Article 2023 05 22 <strong>ABSTRACT</strong> Landslides are a critical geohazard, often triggered by seismic activity, intense rainfall, and water table fluctuations. Understanding the complex interplay of these factors is a key task in hazard assessment and mitigation strategies. This comprehensive study investigates the regional potential for water flow dynamics, displacement mechanisms, and landslide genesis. Based on a dual approach of rigorous fieldwork and meticulous laboratory analysis, approximately 5 kg of fine-grained clay and 100 kg of coarse-grained material were collected for in-depth mechanical property testing. These investigations focused primarily on assessing Atterberg limits and shear strength characteristics. The results showed a striking correlation between the water table and the site's structural integrity. In particular, the marl and alluvial layers exhibited a significant decrease in resistance, ranging from 40% to 55% and 60% to 80%, respectively, in different regions of the study area. In addition, the cohesion of the layers decreased with increasing slope steepness, resulting in a reduction in internal friction angles. This empirical evidence highlights the region's susceptibility to increased landslide risk, particularly in precipitation-induced surface water infiltration and potential seismic upheaval, such as the powerful 7.3 magnitude earthquake in Sarpol Zahab in 2017. These combined factors highlight the imminent threat of landslides and call for proactive risk management and disaster preparedness measures   <strong>Extended Abstract</strong> <strong>Introduction</strong> The landslide on the southern slope of Shahneshin Mountain (Male Kabud) lies within the western region of Kermanshah province, positioned between 45°53' to 45°54' east longitude and 34°31' to 34°33' north latitude, covering an area of 6 square kilometers, this landslide occurred approximately 8 kilometers north of Sarpol-Zahab city. This area's geological structure, influenced by tectonic activities and various climatic periods, has shaped distinct landforms as rocky outcrops, fractures, sharp ridges, valleys, wall-like abysses (known as Giloi), dolines, karens, screes, and springs. Abundant springs and water seepage along valley sides and slopes suggest a proximity of groundwater to the surface, notably visible as springs emerging from joints and cracks during heavy rainfall. This area is situated in the tectonically active Zagros earthquake zone and experiences significant seismic activity. The mountainous terrain, unique geological compositions, and alternating layers of marl and limestone create a predisposition for landslides in this region. These conditions form a landscape where the convergence of factors sets the stage for landslide occurrences.   <strong>Methodology</strong> This article aimed to assess the impact of groundwater on potential landslide occurrences and their influence on underlying formations. It delved into various parameters, including surface water dynamics, cracks, faults, groundwater flow, and geotechnical soil properties. The investigation relied on a comprehensive analysis combining field operations and laboratory studies. Identifying the area's cracks and faults was crucial to understanding surface water infiltration and groundwater flow patterns. Satellite imagery facilitated fault direction measurement, while Branton's compass aided in assessing seams, cracks, and primary ruptures resulting from recent landslides. These observations were then translated into directional and slope representations via rose diagrams using Stereonet software. This multifaceted approach allowed for a comprehensive evaluation of the terrain's vulnerabilities and potential triggers for landslide occurrences. In the subsequent phase, the influence of groundwater on the geotechnical properties of soils underwent a thorough examination. This involved assessing Atterberg limits, shear resistance, adhesion, and internal friction characteristics. To evaluate the alluvial materials and marl beds, samples were obtained both in their dry state and following a 40 mm rainfall event on the slip surface. Laboratory analysis focused on geotechnical features such as Atterberg's limits encompassing shrinkage, plastic, and liquid limits; tests for plastic and liquid limits adhered to Iranian Standard Number 10731. Additionally, direct cutting tests were conducted to measure parameters like adhesion (c) and friction angle (φ). Results from assessing Atterberg's limits and shear strength of alluvial materials and marl beds revealed a noteworthy trend as moisture content increased; the beds exhibited decreased resistance, particularly in marl layers. Given the prevalence of marl formations across numerous sections of the study area, the potential impact of groundwater on slope stability warrants comprehensive investigation.   <strong>Results and discussion</strong> "One of the pivotal factors influencing the occurrence of significant landslides on the southern slope of Shah Neshin Mountain is the presence and influence of groundwater. The stratigraphic column of the studied area comprises limestone-dolomite and marl beds affected by faults, joints, and cracks. This unique combination, including the almost pure Asmari carbonate formation sequences, intense tectonic activity, and numerous joints and fissures, has fostered the development of karst formations within the mountain. The alternation of permeable limestone and impermeable marl beds results in surface water infiltrating through the limestone layers and accumulating on the impermeable <em>marl beds. This water accumulates atop impermeable marl beds, heightening instability</em> within sensitive marl formations and amplifying the risk of landslides. Moreover, the recent landslide-induced cracks, expanding the waterway network, predominantly perpendicular to their direction, impede surface water flow. Consequently, these cracks exacerbate surface water infiltration into the ground, leading to aquifer formation on marl layers, providing ideal conditions for slip occurrences due to their low resistance against water infiltration. The region exhibits a rich presence of groundwater, notably influencing recent landslides and potentially affecting future occurrences. Laboratory analyses on alluvial materials and marl beds confirm a significant decline in resistance attributed to groundwater, particularly pronounced in marl layers. This diminished resistance contributes to landslide occurrences, especially during seismic events and heavy rainfall. The fracture system within the region directs water flow towards lower beds, raising groundwater levels, resulting in the emergence of springs and limited vegetation development. Furthermore, laboratory results indicate a notable decrease in resistance, especially in marl beds, due to water presence, further exacerbating landslide risks in the area. Tectonic movements and earthquakes compromising lower beds' shear resistance and changes in pore water pressure sans precipitation escalate landslide probabilities. The combination of created gaps and preserved waterways amplifies landslide risks during heavy rainfalls or seismic activities akin to the 1918 earthquake. Consequently, this intricate interplay of geological factors and water dynamics accentuates the area's vulnerability to landslide occurrences. "   <strong>Conclusion</strong> "The presence of dense and brittle limestone-dolomite beds, coupled with faults, joints, and fractures within these rock formations, facilitates water infiltration and downward movement into lower beds. Consequently, these waters accumulate on the impermeable marl layers, creating conditions conducive to forming aquifers. A visible manifestation of this process is the emergence of springs and water seepage across the region. The influence of these waters extends to diminishing the resistance of the beds, particularly the marl beds. Laboratory tests assessing Atterberg limits and soil shear strength from both marl and alluvial layers reveal a notable trend as the beds exhibit decreased resistance as moisture content increases. Additionally, with heightened slope angles, adhesion decreases while the angle of internal friction increases. These combined conditions create a favorable environment for landslide occurrences."   <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work. <strong> </strong> <strong>Conflict of Interest</strong> Authors declared no conflict of interest. <strong> </strong> <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. <strong>ABSTRACT</strong> Landslides are a critical geohazard, often triggered by seismic activity, intense rainfall, and water table fluctuations. Understanding the complex interplay of these factors is a key task in hazard assessment and mitigation strategies. This comprehensive study investigates the regional potential for water flow dynamics, displacement mechanisms, and landslide genesis. Based on a dual approach of rigorous fieldwork and meticulous laboratory analysis, approximately 5 kg of fine-grained clay and 100 kg of coarse-grained material were collected for in-depth mechanical property testing. These investigations focused primarily on assessing Atterberg limits and shear strength characteristics. The results showed a striking correlation between the water table and the site's structural integrity. In particular, the marl and alluvial layers exhibited a significant decrease in resistance, ranging from 40% to 55% and 60% to 80%, respectively, in different regions of the study area. In addition, the cohesion of the layers decreased with increasing slope steepness, resulting in a reduction in internal friction angles. This empirical evidence highlights the region's susceptibility to increased landslide risk, particularly in precipitation-induced surface water infiltration and potential seismic upheaval, such as the powerful 7.3 magnitude earthquake in Sarpol Zahab in 2017. These combined factors highlight the imminent threat of landslides and call for proactive risk management and disaster preparedness measures   <strong>Extended Abstract</strong> <strong>Introduction</strong> The landslide on the southern slope of Shahneshin Mountain (Male Kabud) lies within the western region of Kermanshah province, positioned between 45°53' to 45°54' east longitude and 34°31' to 34°33' north latitude, covering an area of 6 square kilometers, this landslide occurred approximately 8 kilometers north of Sarpol-Zahab city. This area's geological structure, influenced by tectonic activities and various climatic periods, has shaped distinct landforms as rocky outcrops, fractures, sharp ridges, valleys, wall-like abysses (known as Giloi), dolines, karens, screes, and springs. Abundant springs and water seepage along valley sides and slopes suggest a proximity of groundwater to the surface, notably visible as springs emerging from joints and cracks during heavy rainfall. This area is situated in the tectonically active Zagros earthquake zone and experiences significant seismic activity. The mountainous terrain, unique geological compositions, and alternating layers of marl and limestone create a predisposition for landslides in this region. These conditions form a landscape where the convergence of factors sets the stage for landslide occurrences.   <strong>Methodology</strong> This article aimed to assess the impact of groundwater on potential landslide occurrences and their influence on underlying formations. It delved into various parameters, including surface water dynamics, cracks, faults, groundwater flow, and geotechnical soil properties. The investigation relied on a comprehensive analysis combining field operations and laboratory studies. Identifying the area's cracks and faults was crucial to understanding surface water infiltration and groundwater flow patterns. Satellite imagery facilitated fault direction measurement, while Branton's compass aided in assessing seams, cracks, and primary ruptures resulting from recent landslides. These observations were then translated into directional and slope representations via rose diagrams using Stereonet software. This multifaceted approach allowed for a comprehensive evaluation of the terrain's vulnerabilities and potential triggers for landslide occurrences. In the subsequent phase, the influence of groundwater on the geotechnical properties of soils underwent a thorough examination. This involved assessing Atterberg limits, shear resistance, adhesion, and internal friction characteristics. To evaluate the alluvial materials and marl beds, samples were obtained both in their dry state and following a 40 mm rainfall event on the slip surface. Laboratory analysis focused on geotechnical features such as Atterberg's limits encompassing shrinkage, plastic, and liquid limits; tests for plastic and liquid limits adhered to Iranian Standard Number 10731. Additionally, direct cutting tests were conducted to measure parameters like adhesion (c) and friction angle (φ). Results from assessing Atterberg's limits and shear strength of alluvial materials and marl beds revealed a noteworthy trend as moisture content increased; the beds exhibited decreased resistance, particularly in marl layers. Given the prevalence of marl formations across numerous sections of the study area, the potential impact of groundwater on slope stability warrants comprehensive investigation.   <strong>Results and discussion</strong> "One of the pivotal factors influencing the occurrence of significant landslides on the southern slope of Shah Neshin Mountain is the presence and influence of groundwater. The stratigraphic column of the studied area comprises limestone-dolomite and marl beds affected by faults, joints, and cracks. This unique combination, including the almost pure Asmari carbonate formation sequences, intense tectonic activity, and numerous joints and fissures, has fostered the development of karst formations within the mountain. The alternation of permeable limestone and impermeable marl beds results in surface water infiltrating through the limestone layers and accumulating on the impermeable <em>marl beds. This water accumulates atop impermeable marl beds, heightening instability</em> within sensitive marl formations and amplifying the risk of landslides. Moreover, the recent landslide-induced cracks, expanding the waterway network, predominantly perpendicular to their direction, impede surface water flow. Consequently, these cracks exacerbate surface water infiltration into the ground, leading to aquifer formation on marl layers, providing ideal conditions for slip occurrences due to their low resistance against water infiltration. The region exhibits a rich presence of groundwater, notably influencing recent landslides and potentially affecting future occurrences. Laboratory analyses on alluvial materials and marl beds confirm a significant decline in resistance attributed to groundwater, particularly pronounced in marl layers. This diminished resistance contributes to landslide occurrences, especially during seismic events and heavy rainfall. The fracture system within the region directs water flow towards lower beds, raising groundwater levels, resulting in the emergence of springs and limited vegetation development. Furthermore, laboratory results indicate a notable decrease in resistance, especially in marl beds, due to water presence, further exacerbating landslide risks in the area. Tectonic movements and earthquakes compromising lower beds' shear resistance and changes in pore water pressure sans precipitation escalate landslide probabilities. The combination of created gaps and preserved waterways amplifies landslide risks during heavy rainfalls or seismic activities akin to the 1918 earthquake. Consequently, this intricate interplay of geological factors and water dynamics accentuates the area's vulnerability to landslide occurrences. "   <strong>Conclusion</strong> "The presence of dense and brittle limestone-dolomite beds, coupled with faults, joints, and fractures within these rock formations, facilitates water infiltration and downward movement into lower beds. Consequently, these waters accumulate on the impermeable marl layers, creating conditions conducive to forming aquifers. A visible manifestation of this process is the emergence of springs and water seepage across the region. The influence of these waters extends to diminishing the resistance of the beds, particularly the marl beds. Laboratory tests assessing Atterberg limits and soil shear strength from both marl and alluvial layers reveal a notable trend as the beds exhibit decreased resistance as moisture content increases. Additionally, with heightened slope angles, adhesion decreases while the angle of internal friction increases. These combined conditions create a favorable environment for landslide occurrences."   <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work. <strong> </strong> <strong>Conflict of Interest</strong> Authors declared no conflict of interest. <strong> </strong> <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. https://jphgr.ut.ac.ir/article_95006_c98863cfef02621aedcf764b76373e4d.pdf

University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 01 Analysis of Distribution of Temporal-Spatial Trend of Horizontal Visibility on the Southern Coasts of the Caspian Sea using Ridit Analysis Analysis of Distribution of Temporal-Spatial Trend of Horizontal Visibility on the Southern Coasts of the Caspian Sea using Ridit Analysis 37 54 94901 10.22059/jphgr.2023.362522.1007784 FA Behroz Sobhani Department of Climatology, Faculty of Social Sciences,University of Mohaghegh Ardabili, Ardabil, Iran Leyla Jafarzadeh Aliabad Department of Climatology, Faculty of Social Sciences, University of Mohaghegh Ardabili, Ardabil, Iran Golamhasan Mohammadi Department of Climatology, Faculty of Planning and Environmental Sciences, Tabriz University, Tabriz, Iran Journal Article 2023 05 22 <strong>Analysis of Distribution of Temporal-Spatial Trend of Horizontal Visibility on the Southern Coasts of the Caspian Sea using Ridit Analysis</strong><br /><strong> ABSTRACT</strong><br />The present study aims to investigate the temporal-spatial trend of horizontal visibility in the southern coasts of the Caspian Sea. For this purpose, horizontal visibility and climatic parameters (relative humidity, temperature, precipitation, and wind speed) were obtained in 13 selected meteorological stations from 1951-2010. After the data screening, the temporal changes of the perspective were examined. Also, Ridit tests were applied to examine the trend of horizontal visibility, and a correlation coefficient was used to identify the relationship between the climatic parameters effective in reducing horizontal visibility. The results of the research showed that the average annual dispersion of horizontal visibility in the studied stations experienced relatively different periods; the first period from 1951 to 1976 period of horizontal increase, the second period from 1977 to 1985 period of noticeable decline, the third period from 1986 to 2002 fixed period (no fundamental change) and the fourth period from 2003 to 2020 relative increase. Among the stations, the highest negative correlation coefficient was experienced by Astara station, with a value of -0.47, and the lowest was experienced by Sari station, with a value of -0.07. In the correlation between horizontal visibility and precipitation in the studied stations, the maximum significant negative correlation was observed in the Manjil station (with a value of -0.15) and the least in the Maratape station (with a value of -0.012). The correlation between horizontal visibility and temperature is direct and positive in most stations, and the maximum positive correlation is assigned to the Astara station with a value of 0.38. It also showed a negative correlation between wind speed and horizontal visibility. The inverse correlation's maximum and minimum range fluctuates between -0.28 in Sari and -0.08 in Babolsar<br /><strong>Extended abstract</strong><br /><strong>Introduction</strong><br />Horizontal visibility is one of the indicators of air quality. Atmospheric visibility refers to the maximum horizontal distance at which a person with naked eyes can detect objects on the ground. The range of visibility in a clear atmosphere is between 145 and 225 kilometers; in a normal atmosphere, it is between 10 to 100 kilometers, and in polluted areas, it is less. Horizontal visibility depends on the level and concentration of air pollutants, and its relationship with temperature and weather conditions is of particular interest in the studied region. This research aims to obtain the necessary information and specialized and public use of meteorological and climatological station data in northern Iran concerning natural disaster planning and prevention of resulting hazards in the studied area.<br /> <br /><strong>Methodology</strong><br />This research was conducted on the southern coasts of the Caspian Sea, which includes three provinces. All three provinces are located downstream from the Caspian Sea and are highly humid. First, filtering was done so that the data related to the hours of the day 06, 09, 12, and 15 Greenwich synopses were used, and also, the synopses with missing horizontal visibility and precipitation phenomena and relative humidity above 90% were screened. Then, to analyze the data, the annual average changes in horizontal visibility were checked by calculating the regional average and drawing a graph. Ridit analysis was used to analyze the behavior of horizontal visibility during the study period in selected stations. Finally, using the correlation coefficient, the relationship between the climatic parameters of the horizontal wind in the region was examined. ArcGIS software prepared horizontal visibility spatial distribution maps with climatic parameters.<br /> <br /><strong>Results and discussion</strong><br />From 1951 to 1976, the first period had a mostly higher average horizontal visibility, ranging from 17 to 5.21 kilometers. The second period, covering the years 1977 to 1985, experienced a significant decrease in horizontal visibility, with its average decreasing to 10 kilometers. The third period, from 1986 to 2002, was stable, with only minor fluctuations in the average horizontal visibility (1 kilometer). The fourth period, from 2003 to 2020, was a period of relative improvement in the average horizontal visibility, with a relatively high variability. Among the studied stations, Babolsar and Ramsar stations experienced an increasing trend compared to the regional average. The average horizontal visibility trend analysis showed a decrease from early winter to early spring, with its value reaching 8.11 kilometers in March. From mid-spring to late summer, horizontal visibility increased, with the highest average in June at 8.12 kilometers. In the autumn, a relative increase in horizontal visibility was observed, with the highest average reaching 13 kilometers in March. Almost all studied stations in the region followed a similar pattern, except for Babolsar and Qara Khial stations. In the spring season, the eastern part of the region has higher horizontal visibility compared to the western part. The maximum horizontal visibility is observed in the coastal strip of the Caspian Sea in the summer. This season, the southernmost part of the region, which is close to the Alborz Mountains, has lower horizontal visibility. As we approach the Alborz Mountains in the autumn, horizontal visibility decreases due to increased precipitation and fog. Horizontal visibility increases in the western and eastern parts of the region, respectively. In the winter season, the lowest horizontal visibility is concentrated in the southernmost part of the region. The results of the RIDIT analysis for selected stations showed that the Babolsar station had the best horizontal visibility conditions at the beginning of the study period and the worst conditions at the end of the period, showing a decreasing trend in horizontal visibility overall. The horizontal visibility at Ramsar station showed a decreasing trend from the beginning to the end of the study period, with RIDIT values ranging from 0.6 to 4.0. The Astara station had a decreasing trend in horizontal visibility, with RIDIT values ranging from 5.0 to 4.0, which is very close to the reference distribution conditions. The Nowshahr station showed an increasing trend in horizontal visibility, with a relatively small difference in RIDIT values ranging from 4.0 to 6.0, close to the reference distribution line. The Gonbad Kavus station showed no trend in horizontal visibility, with very little difference in RIDIT values. The Maraveh Tappeh station had a very small difference in RIDIT values throughout the study period. The spatial distribution of RIDIT analysis for annual scales showed that Maraveh Tappeh, Gonbad Kavus in the eastern region, and Nowshahr near the coastal strip had no trend in horizontal visibility conditions. The Babolsar and Ramsar stations near the coastal strip showed an increasing trend in horizontal visibility. The Astara station in the northwest of the region had a decreasing trend. In the spring and summer, the Nowshahr and Ramsar stations near the Caspian Sea experienced a decreasing trend, while Babolsar station had an increasing trend. In the autumn, the Nowshahr and Astara stations had a decreasing trend, while the Ramsar station had an increasing trend. In the winter, a decreasing trend was observed in the Babolsar, Nowshahr, and Astara stations, while an increasing trend was observed in the Ramsar station near the coastal line. The correlation between relative humidity and horizontal visibility showed a negative correlation coefficient in the study area. In the annual scale, the Astara, Bandar Anzali, Nowshahr, Gonbad Kavus, and Siah Bisheh stations showed a relatively strong inverse relationship between relative humidity and horizontal visibility, with a range of values from -23.0 to -47.0. On the monthly scale, the same stations showed a range of values from -25.0 to -47.0. The correlation between horizontal visibility and precipitation in the area was positive and negative. A significant correlation between horizontal visibility and precipitation was found in 27% of the area. The correlation between horizontal visibility and temperature was direct and significant in 72% of the area. The correlation between horizontal visibility and wind speed was direct and inverse, significant in 54% of the area.<br /><strong> </strong><br /><strong>Conclusion</strong><br />The results indicate that the annual mean of horizontal visibility in the study stations shows four relatively different periods. The most significant number of stations with a decreasing trend compared to other seasons was observed in winter. The spatial distribution of horizontal visibility on an annual scale shows that horizontal visibility has been higher in the eastern region compared to the western region. The results of the correlation analysis between horizontal visibility and climatic parameters showed that the correlation coefficient between horizontal visibility and precipitation was both direct and inverse, and 27% of the area had a significant correlation.<br />                                      <br /><strong>Funding</strong><br />There is no funding support.<br /> <br /><strong>Authors’ Contribution</strong><br />All of the authors approved the content of the manuscript and agreed on all aspects of the work.<br /> <br /><strong>Conflict of Interest</strong><br />Authors declared no conflict of interest.<br /> <br /><strong>Acknowledgments</strong><br />We are grateful to all the scientific consultants of this paper.<br />  <strong>Analysis of Distribution of Temporal-Spatial Trend of Horizontal Visibility on the Southern Coasts of the Caspian Sea using Ridit Analysis</strong><br /><strong> ABSTRACT</strong><br />The present study aims to investigate the temporal-spatial trend of horizontal visibility in the southern coasts of the Caspian Sea. For this purpose, horizontal visibility and climatic parameters (relative humidity, temperature, precipitation, and wind speed) were obtained in 13 selected meteorological stations from 1951-2010. After the data screening, the temporal changes of the perspective were examined. Also, Ridit tests were applied to examine the trend of horizontal visibility, and a correlation coefficient was used to identify the relationship between the climatic parameters effective in reducing horizontal visibility. The results of the research showed that the average annual dispersion of horizontal visibility in the studied stations experienced relatively different periods; the first period from 1951 to 1976 period of horizontal increase, the second period from 1977 to 1985 period of noticeable decline, the third period from 1986 to 2002 fixed period (no fundamental change) and the fourth period from 2003 to 2020 relative increase. Among the stations, the highest negative correlation coefficient was experienced by Astara station, with a value of -0.47, and the lowest was experienced by Sari station, with a value of -0.07. In the correlation between horizontal visibility and precipitation in the studied stations, the maximum significant negative correlation was observed in the Manjil station (with a value of -0.15) and the least in the Maratape station (with a value of -0.012). The correlation between horizontal visibility and temperature is direct and positive in most stations, and the maximum positive correlation is assigned to the Astara station with a value of 0.38. It also showed a negative correlation between wind speed and horizontal visibility. The inverse correlation's maximum and minimum range fluctuates between -0.28 in Sari and -0.08 in Babolsar<br /><strong>Extended abstract</strong><br /><strong>Introduction</strong><br />Horizontal visibility is one of the indicators of air quality. Atmospheric visibility refers to the maximum horizontal distance at which a person with naked eyes can detect objects on the ground. The range of visibility in a clear atmosphere is between 145 and 225 kilometers; in a normal atmosphere, it is between 10 to 100 kilometers, and in polluted areas, it is less. Horizontal visibility depends on the level and concentration of air pollutants, and its relationship with temperature and weather conditions is of particular interest in the studied region. This research aims to obtain the necessary information and specialized and public use of meteorological and climatological station data in northern Iran concerning natural disaster planning and prevention of resulting hazards in the studied area.<br /> <br /><strong>Methodology</strong><br />This research was conducted on the southern coasts of the Caspian Sea, which includes three provinces. All three provinces are located downstream from the Caspian Sea and are highly humid. First, filtering was done so that the data related to the hours of the day 06, 09, 12, and 15 Greenwich synopses were used, and also, the synopses with missing horizontal visibility and precipitation phenomena and relative humidity above 90% were screened. Then, to analyze the data, the annual average changes in horizontal visibility were checked by calculating the regional average and drawing a graph. Ridit analysis was used to analyze the behavior of horizontal visibility during the study period in selected stations. Finally, using the correlation coefficient, the relationship between the climatic parameters of the horizontal wind in the region was examined. ArcGIS software prepared horizontal visibility spatial distribution maps with climatic parameters.<br /> <br /><strong>Results and discussion</strong><br />From 1951 to 1976, the first period had a mostly higher average horizontal visibility, ranging from 17 to 5.21 kilometers. The second period, covering the years 1977 to 1985, experienced a significant decrease in horizontal visibility, with its average decreasing to 10 kilometers. The third period, from 1986 to 2002, was stable, with only minor fluctuations in the average horizontal visibility (1 kilometer). The fourth period, from 2003 to 2020, was a period of relative improvement in the average horizontal visibility, with a relatively high variability. Among the studied stations, Babolsar and Ramsar stations experienced an increasing trend compared to the regional average. The average horizontal visibility trend analysis showed a decrease from early winter to early spring, with its value reaching 8.11 kilometers in March. From mid-spring to late summer, horizontal visibility increased, with the highest average in June at 8.12 kilometers. In the autumn, a relative increase in horizontal visibility was observed, with the highest average reaching 13 kilometers in March. Almost all studied stations in the region followed a similar pattern, except for Babolsar and Qara Khial stations. In the spring season, the eastern part of the region has higher horizontal visibility compared to the western part. The maximum horizontal visibility is observed in the coastal strip of the Caspian Sea in the summer. This season, the southernmost part of the region, which is close to the Alborz Mountains, has lower horizontal visibility. As we approach the Alborz Mountains in the autumn, horizontal visibility decreases due to increased precipitation and fog. Horizontal visibility increases in the western and eastern parts of the region, respectively. In the winter season, the lowest horizontal visibility is concentrated in the southernmost part of the region. The results of the RIDIT analysis for selected stations showed that the Babolsar station had the best horizontal visibility conditions at the beginning of the study period and the worst conditions at the end of the period, showing a decreasing trend in horizontal visibility overall. The horizontal visibility at Ramsar station showed a decreasing trend from the beginning to the end of the study period, with RIDIT values ranging from 0.6 to 4.0. The Astara station had a decreasing trend in horizontal visibility, with RIDIT values ranging from 5.0 to 4.0, which is very close to the reference distribution conditions. The Nowshahr station showed an increasing trend in horizontal visibility, with a relatively small difference in RIDIT values ranging from 4.0 to 6.0, close to the reference distribution line. The Gonbad Kavus station showed no trend in horizontal visibility, with very little difference in RIDIT values. The Maraveh Tappeh station had a very small difference in RIDIT values throughout the study period. The spatial distribution of RIDIT analysis for annual scales showed that Maraveh Tappeh, Gonbad Kavus in the eastern region, and Nowshahr near the coastal strip had no trend in horizontal visibility conditions. The Babolsar and Ramsar stations near the coastal strip showed an increasing trend in horizontal visibility. The Astara station in the northwest of the region had a decreasing trend. In the spring and summer, the Nowshahr and Ramsar stations near the Caspian Sea experienced a decreasing trend, while Babolsar station had an increasing trend. In the autumn, the Nowshahr and Astara stations had a decreasing trend, while the Ramsar station had an increasing trend. In the winter, a decreasing trend was observed in the Babolsar, Nowshahr, and Astara stations, while an increasing trend was observed in the Ramsar station near the coastal line. The correlation between relative humidity and horizontal visibility showed a negative correlation coefficient in the study area. In the annual scale, the Astara, Bandar Anzali, Nowshahr, Gonbad Kavus, and Siah Bisheh stations showed a relatively strong inverse relationship between relative humidity and horizontal visibility, with a range of values from -23.0 to -47.0. On the monthly scale, the same stations showed a range of values from -25.0 to -47.0. The correlation between horizontal visibility and precipitation in the area was positive and negative. A significant correlation between horizontal visibility and precipitation was found in 27% of the area. The correlation between horizontal visibility and temperature was direct and significant in 72% of the area. The correlation between horizontal visibility and wind speed was direct and inverse, significant in 54% of the area.<br /><strong> </strong><br /><strong>Conclusion</strong><br />The results indicate that the annual mean of horizontal visibility in the study stations shows four relatively different periods. The most significant number of stations with a decreasing trend compared to other seasons was observed in winter. The spatial distribution of horizontal visibility on an annual scale shows that horizontal visibility has been higher in the eastern region compared to the western region. The results of the correlation analysis between horizontal visibility and climatic parameters showed that the correlation coefficient between horizontal visibility and precipitation was both direct and inverse, and 27% of the area had a significant correlation.<br />                                      <br /><strong>Funding</strong><br />There is no funding support.<br /> <br /><strong>Authors’ Contribution</strong><br />All of the authors approved the content of the manuscript and agreed on all aspects of the work.<br /> <br /><strong>Conflict of Interest</strong><br />Authors declared no conflict of interest.<br /> <br /><strong>Acknowledgments</strong><br />We are grateful to all the scientific consultants of this paper.<br />  https://jphgr.ut.ac.ir/article_94901_25cafb9038bb5c3dd2914ff83650400c.pdf

University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 03 Effects of Geomorphology of Alluvial Fans on the Physical and Chemical Changes of the soil of Alluvial Fan in the Southeast of Shah Gheib’s Salt Dome, Larestan Effects of Geomorphology of Alluvial Fans on the Physical and Chemical Changes of the soil of Alluvial Fan in the Southeast of Shah Gheib’s Salt Dome, Larestan 55 70 94814 10.22059/jphgr.2023.361957.1007782 FA Seyedeh Bayan Azizi Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Shahram Bahrami Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Somayeh Khaleghi Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Ahmadreza Mehrabian Faculty of Biological Sciences and Technology, Shahid Beheshti University, Tehran, Iran Journal Article 2023 05 24 <strong>ABSTRACT</strong><br />Alluvial fans are ideal places for investigating the effects of geomorphological processes and landforms on soil properties. This study aimed to investigate the effects of geomorphological forms and processes on physical and chemical properties of soil in an alluvial fan located in the southeast of Shah Ghaib salt diaper. The study area alluvial fan is composed of three surfaces including very old, old and young. The phosphorous, potassium, absorbable sodium, calcium carbonate, saturation moisture of soil, water’s holding capacity in soil, soil texture, and organic carbon parameters were measured in 72 soil samples on the alluvial fan surfaces.The results showed that the sodium, potassium, EC, calcium carbonate, phosphorous, and holding capacity of water, silt, and clay parameters were higher in the interfluves than the channels in inactive (very old and old) surfaces. The organic carbon, pH, saturation moisture of soil and percentage of sand is higher in the channels. Also, the sodium, potassium, EC were more in the young compared to the old and very old surfaces. The PH, phosphorous, and saturation moisture of soil were higher in the old surface than in the young and very old ones. The amount of calcium carbonate, water’s holding capacity in soil and percentage of silt were highest in the very old fan surface. The correlation coefficient between the measured parameters of the soil indicated that there are strong positive relationships between the clay and the sodium, electrical conductivity, calcium carbonate, and potassium. In general, the results show that geomorphological processes such as entrenchment in channels and weathering on the surface of the interfluves have controlled on the values of the physicochemical parameters of the soil in the study area alluvial fan<br /> <br /><strong>Extended Abstract</strong><br /><strong>Introduction</strong><br />As the thin layer of the earth's surface, soil changes continuously over time. This change occurs due to the effects of various factors. Geomorphological forms and processes can affect the physicochemical properties of soil. Alluvial fans are one of the most widespread landforms in Iran. Alluvial fans developed around salt diapirs of Zagros mountains are ideal places for investigating the effects of geomorphological landforms and processes on soil properties. The movement of diapir salts on the apex of alluvial fans can change the location of channel and sedimentation and, hence, the physicochemical properties of soil. This study aimed to investigate the effects of geomorphological forms and processes on soil's physical and chemical properties in an alluvial fan developed in the southeast of Shah Ghaib salt diapir in Larestan, Fars, Iran. The mentioned alluvial fan comprises three surfaces as very old, old, and young. The phosphorous, potassium, absorbable sodium, calcium carbonate, soil's saturation moisture, water's holding capacity, soil texture, and organic carbon parameters of 72 soil samples on the alluvial fan surfaces were measured.<br /><strong> </strong><br /><strong>Methodology</strong><br /><strong> </strong>In order to achieve the aim of this study, the borders of the studied alluvial fan surfaces were delineated by Google Earth images and field observation, and then the areas of three very old, old, and young surfaces were determined. A field survey was conducted in December 2021 to study the morphology and processes of the study area alluvial fan. Also, to analyze the physical and chemical properties of the studied alluvial fan, 9 plots in the apex, mid-fan, and toe of the very old, old, and young surfaces were selected. Seventy-two soil samples (24 samples for each surface) were acquired from locations (apex, mid-fan, and toe) and various landforms (channels, interfluves, bars, and swales) of the studied alluvial fan. The soil samples were then transferred to a laboratory. Ec, pH, phosphorous (P), potassium (K), absorbable sodium (Na), calcium carbonate (Caco), soil’s saturation moisture (Sp), water’s holding capacity in soil (WHC), soil texture (Texture) and total organic carbon (OCT) tests were conducted. The mean physical and chemical properties of soil on different surfaces (very old, old, and young) and in different landforms on inactive (channels and interfluves) and active (bars and swales) surfaces and also on different locations (apex, mid-fan, and toe) were calculated, and the results were compared. Later, the Pearson correlation coefficient was used to investigate the relationship between soil properties. Finally, the relationship between soil properties and fan morphology was analyzed.<br /><strong> </strong><br /><strong>Results and Discussion</strong><br />A comparison of data in the landforms of inactive (very old and old) surfaces indicated that the sodium, potassium, EC, lime, phosphorous, and water holding in soil, silt, and clay parameters were higher in the interfluves than the channels. The higher amounts of the mentioned factors in the interfluves can be attributed to the more excellent weathering and soil formation and the lower topographic gradients of the interfluves compared to the channels. In channels, incision and erosion processes are predominant, reducing parameters such as potassium, sodium, and water’s holding capacity in soil, clay, and silt. Results show that organic carbon is higher in channels than interfluves, possibly due to the higher vegetation density and canopy. Despite the richer soil of the interfluves compared to the channels of old and very old surfaces, the channels are more conducive for vegetation due to their shading and greater moisture, which could increase the organic carbon of soils in the channels. Data indicate that the amount of soil sodium on the new surface is much higher than on old and very old surfaces. This can be due to salt formations (Shah Ghaib salt diapir) in the drainage basin of the alluvial fan. Meanwhile, floods and runoffs in the basin only feed the young surface of the alluvial fan, resulting in the soil salinity.<br />On the other hand, the alluvial fan's old and very old surfaces have been abandoned and are not affected by the floods. The alluvial fan's old and very old surfaces are washed by rainfalls and runoffs each year, reducing their salinity. Results have demonstrated that the sodium, pH, limestone, organic carbon, and clay parameters are greater in the apex of the fan, while the phosphorous, silt, and gravel are greater in the toe of the alluvial fan. The correlation coefficient between the measured parameters of the soil indicated positive and significant relationships between clay and sodium, electrical conductivity, calcium carbonate, and potassium. Results also show sodium positively and significantly correlated with potassium and Ec. The Ec shows the soil's ability to conduct electrical currents. The most important effect left by electrical conductivity on soil fertility is that electrical conductivity is an indicator of access to nutrients in soil. Electrical conductivity is often low in sandy soils with low organic carbon. In soils with high clay content, electrical conductivity is high. The clay, Ec, sodium, and potassium are high in interfluves but low in channels.<br /><strong> </strong><br /><strong>Conclusion</strong><br />The studied alluvial fan is located southeast of Shah Ghaib diapir in Fars Province. Under the influence of salt movement towards the downslope, the stream flow in the basin outlet or the fan apex has been repeatedly relocated during the past hundreds or thousands of years, and hence, parts of alluvial fan (very old or old surfaces), have been subsequently abandoned, resulting in changing geomorphological forms and processes during previous periods. The morphological survey of the studied alluvial fan indicated that old and very old surfaces had been incised by erosive channels and had rough surfaces. In contrast, the young surface of the fan with swale and bar landforms was almost smooth. The interfluves of old and very old surfaces are affected by weathering and soil formation because much time has passed since their last flooding and sedimentation activities. At the same time, channels have been subjected to incision and erosion. Findings showed that the sodium, potassium, EC, lime, phosphorous, water holding in soil, silt, and clay factors were greater in the interfluves than in the channels. The higher amounts of the mentioned elements can be due to greater weathering and soil formation and the lower topographic slopes of the interfluves than the channels. The higher amount of organic carbon in the channels than the interfluves can be attributed to the vegetation density and canopy of the channels compared to the interfluves. Data also suggested a higher amount of soil sodium on the young surface compared to the old and old surfaces, which may be due to salt formations (Shah Ghaib salt diapir) in the drainage basin of the young surface of the fan. In general, the active processes on the alluvial surfaces, the difference in the relative age of various surfaces, and the lithology of the upstream drainage basin are among the most important factors controlling the physicochemical properties of the studied alluvial fan’s soil.<br /> <br /><strong>Funding</strong><br />There is no funding support.<br /> <br /><strong>Authors’ Contribution</strong><br />All of the authors approved the content of the manuscript and agreed on all aspects of the work.<br /><strong> </strong><br /><strong>Conflict of Interest</strong><br />Authors declared no conflict of interest.<br /><strong> </strong><br /><strong>Acknowledgments</strong><br />We are grateful to all the scientific consultants of this paper. <strong>ABSTRACT</strong><br />Alluvial fans are ideal places for investigating the effects of geomorphological processes and landforms on soil properties. This study aimed to investigate the effects of geomorphological forms and processes on physical and chemical properties of soil in an alluvial fan located in the southeast of Shah Ghaib salt diaper. The study area alluvial fan is composed of three surfaces including very old, old and young. The phosphorous, potassium, absorbable sodium, calcium carbonate, saturation moisture of soil, water’s holding capacity in soil, soil texture, and organic carbon parameters were measured in 72 soil samples on the alluvial fan surfaces.The results showed that the sodium, potassium, EC, calcium carbonate, phosphorous, and holding capacity of water, silt, and clay parameters were higher in the interfluves than the channels in inactive (very old and old) surfaces. The organic carbon, pH, saturation moisture of soil and percentage of sand is higher in the channels. Also, the sodium, potassium, EC were more in the young compared to the old and very old surfaces. The PH, phosphorous, and saturation moisture of soil were higher in the old surface than in the young and very old ones. The amount of calcium carbonate, water’s holding capacity in soil and percentage of silt were highest in the very old fan surface. The correlation coefficient between the measured parameters of the soil indicated that there are strong positive relationships between the clay and the sodium, electrical conductivity, calcium carbonate, and potassium. In general, the results show that geomorphological processes such as entrenchment in channels and weathering on the surface of the interfluves have controlled on the values of the physicochemical parameters of the soil in the study area alluvial fan<br /> <br /><strong>Extended Abstract</strong><br /><strong>Introduction</strong><br />As the thin layer of the earth's surface, soil changes continuously over time. This change occurs due to the effects of various factors. Geomorphological forms and processes can affect the physicochemical properties of soil. Alluvial fans are one of the most widespread landforms in Iran. Alluvial fans developed around salt diapirs of Zagros mountains are ideal places for investigating the effects of geomorphological landforms and processes on soil properties. The movement of diapir salts on the apex of alluvial fans can change the location of channel and sedimentation and, hence, the physicochemical properties of soil. This study aimed to investigate the effects of geomorphological forms and processes on soil's physical and chemical properties in an alluvial fan developed in the southeast of Shah Ghaib salt diapir in Larestan, Fars, Iran. The mentioned alluvial fan comprises three surfaces as very old, old, and young. The phosphorous, potassium, absorbable sodium, calcium carbonate, soil's saturation moisture, water's holding capacity, soil texture, and organic carbon parameters of 72 soil samples on the alluvial fan surfaces were measured.<br /><strong> </strong><br /><strong>Methodology</strong><br /><strong> </strong>In order to achieve the aim of this study, the borders of the studied alluvial fan surfaces were delineated by Google Earth images and field observation, and then the areas of three very old, old, and young surfaces were determined. A field survey was conducted in December 2021 to study the morphology and processes of the study area alluvial fan. Also, to analyze the physical and chemical properties of the studied alluvial fan, 9 plots in the apex, mid-fan, and toe of the very old, old, and young surfaces were selected. Seventy-two soil samples (24 samples for each surface) were acquired from locations (apex, mid-fan, and toe) and various landforms (channels, interfluves, bars, and swales) of the studied alluvial fan. The soil samples were then transferred to a laboratory. Ec, pH, phosphorous (P), potassium (K), absorbable sodium (Na), calcium carbonate (Caco), soil’s saturation moisture (Sp), water’s holding capacity in soil (WHC), soil texture (Texture) and total organic carbon (OCT) tests were conducted. The mean physical and chemical properties of soil on different surfaces (very old, old, and young) and in different landforms on inactive (channels and interfluves) and active (bars and swales) surfaces and also on different locations (apex, mid-fan, and toe) were calculated, and the results were compared. Later, the Pearson correlation coefficient was used to investigate the relationship between soil properties. Finally, the relationship between soil properties and fan morphology was analyzed.<br /><strong> </strong><br /><strong>Results and Discussion</strong><br />A comparison of data in the landforms of inactive (very old and old) surfaces indicated that the sodium, potassium, EC, lime, phosphorous, and water holding in soil, silt, and clay parameters were higher in the interfluves than the channels. The higher amounts of the mentioned factors in the interfluves can be attributed to the more excellent weathering and soil formation and the lower topographic gradients of the interfluves compared to the channels. In channels, incision and erosion processes are predominant, reducing parameters such as potassium, sodium, and water’s holding capacity in soil, clay, and silt. Results show that organic carbon is higher in channels than interfluves, possibly due to the higher vegetation density and canopy. Despite the richer soil of the interfluves compared to the channels of old and very old surfaces, the channels are more conducive for vegetation due to their shading and greater moisture, which could increase the organic carbon of soils in the channels. Data indicate that the amount of soil sodium on the new surface is much higher than on old and very old surfaces. This can be due to salt formations (Shah Ghaib salt diapir) in the drainage basin of the alluvial fan. Meanwhile, floods and runoffs in the basin only feed the young surface of the alluvial fan, resulting in the soil salinity.<br />On the other hand, the alluvial fan's old and very old surfaces have been abandoned and are not affected by the floods. The alluvial fan's old and very old surfaces are washed by rainfalls and runoffs each year, reducing their salinity. Results have demonstrated that the sodium, pH, limestone, organic carbon, and clay parameters are greater in the apex of the fan, while the phosphorous, silt, and gravel are greater in the toe of the alluvial fan. The correlation coefficient between the measured parameters of the soil indicated positive and significant relationships between clay and sodium, electrical conductivity, calcium carbonate, and potassium. Results also show sodium positively and significantly correlated with potassium and Ec. The Ec shows the soil's ability to conduct electrical currents. The most important effect left by electrical conductivity on soil fertility is that electrical conductivity is an indicator of access to nutrients in soil. Electrical conductivity is often low in sandy soils with low organic carbon. In soils with high clay content, electrical conductivity is high. The clay, Ec, sodium, and potassium are high in interfluves but low in channels.<br /><strong> </strong><br /><strong>Conclusion</strong><br />The studied alluvial fan is located southeast of Shah Ghaib diapir in Fars Province. Under the influence of salt movement towards the downslope, the stream flow in the basin outlet or the fan apex has been repeatedly relocated during the past hundreds or thousands of years, and hence, parts of alluvial fan (very old or old surfaces), have been subsequently abandoned, resulting in changing geomorphological forms and processes during previous periods. The morphological survey of the studied alluvial fan indicated that old and very old surfaces had been incised by erosive channels and had rough surfaces. In contrast, the young surface of the fan with swale and bar landforms was almost smooth. The interfluves of old and very old surfaces are affected by weathering and soil formation because much time has passed since their last flooding and sedimentation activities. At the same time, channels have been subjected to incision and erosion. Findings showed that the sodium, potassium, EC, lime, phosphorous, water holding in soil, silt, and clay factors were greater in the interfluves than in the channels. The higher amounts of the mentioned elements can be due to greater weathering and soil formation and the lower topographic slopes of the interfluves than the channels. The higher amount of organic carbon in the channels than the interfluves can be attributed to the vegetation density and canopy of the channels compared to the interfluves. Data also suggested a higher amount of soil sodium on the young surface compared to the old and old surfaces, which may be due to salt formations (Shah Ghaib salt diapir) in the drainage basin of the young surface of the fan. In general, the active processes on the alluvial surfaces, the difference in the relative age of various surfaces, and the lithology of the upstream drainage basin are among the most important factors controlling the physicochemical properties of the studied alluvial fan’s soil.<br /> <br /><strong>Funding</strong><br />There is no funding support.<br /> <br /><strong>Authors’ Contribution</strong><br />All of the authors approved the content of the manuscript and agreed on all aspects of the work.<br /><strong> </strong><br /><strong>Conflict of Interest</strong><br />Authors declared no conflict of interest.<br /><strong> </strong><br /><strong>Acknowledgments</strong><br />We are grateful to all the scientific consultants of this paper. https://jphgr.ut.ac.ir/article_94814_5451324760815259faf223d114f00a3b.pdf

University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 03 Temporal and spatial zoning of flood risk in Karganrood catchment using AWBM model and Fuzzy-ANP method Temporal and spatial zoning of flood risk in Karganrood catchment using AWBM model and Fuzzy-ANP method 71 88 94291 10.22059/jphgr.2023.361608.1007778 FA Seyyed Asadullah Hejazi Department of Geomorphology, Faculty of Planning and Environmental Sciences, University of Tabriz, Tabriz, Iran Kosar Loghmannia Department of Geomorphology, Faculty of Planning and Environmental Sciences, University of Tabriz, Tabriz, Iran Journal Article 2023 05 24 <strong>ABSTRACT</strong> Evaluating the flood potential of different watersheds is one of the important measures in the field of reducing damages caused by floods. As one of the flood-prone basins of Gilan province, the River catchment has always caused a lot of damage to the residents of the region in recent years. Therefore, due to the lack of studies in this basin, the current research has attempted to zonate the risk of flooding, and for this purpose, the AWBM model and the Fuzzy-ANP method have been used. , 2014, 2017 and the end of 2018 are estimated to increase and equal to the floods of 1990, 1993, 199, and 1997. In the spatial zoning of flood risk, 10 effective factors incluincludingecipitation, temperature, distance from the river, slope, slope direction, height, land use, vegetation, geolo   and soil were used. In the analysis of the results, it is estimated that the highest risk of flooding is in the southern areas and the outlet of the basin to the Caspian Sea, and the settlement in the river, lack of attention to watershed management, destruction of forests and pastures, and land use change are among the most important factors affecting this issue. In total, 90.3% of the area of the basin has the highest risk of flooding from a geographical point of view <strong>Extended Abstract</strong> <strong>Introduction</strong> Each of the effective factors in causing floods has a different contribution to the risk of its occurrence at the level of catchment basins so that each can be prioritized according to its importance in the region. Reclamation of watersheds for flood control in one project is impractical due to its large size, expansion of impervious areas, and economic and operational issues that can increase flooding. The temporal or spatial zoning of flood risk in this area has not been done with any of the selected models, and the relevant authorities rarely take measures to reduce flood damage. More research is needed in this field to study the basin properly. This study was conducted with the aim of flood risk zoning using two AWBM and Fuzzy-ANP models.   <strong>Methodology </strong> Monthly evapotranspiration, river flow, and precipitation data from 2006 to 2018 were used to simulate the runoff volume of Kerganrood Talesh River using the AWBM model for time zoning. The research used data from synoptic and hydrometric stations in Hashtpar, Lisar, Mashinkhaneh, Sheikh Darun Shandol, Kishli, Khan Balaghi, Piseson, and Davor Ardabil, prepared by the synoptic and Hydrometrical stations of Gilan and Ardabil Provinces. The required data is first arranged in Excel, in the format of RRL software, then it is defined for the model, and based on 9 parameters determined by the software itself, the simulation has been done to estimate the runoff and flood of this basin. This method evaluates the model's accuracy in simulating the observational data using the Nash-Sutcliffe coefficient index (EN2) as the objective function and the explanation coefficient (R2). Additionally, the sensitivity level of the parameters used in the model is investigated in the studied area. In order to conduct spatial zoning, Cochran's formula was used to calculate the statistical sample size. Then, 30 questionnaires were distributed among experts in the field based on the research objective. The purpose, criteria, and sub-criteria of the Super Decision software were determined, and 10 indicators were selected, which are factors such as geology, slope, land use, digital elevation model (DEM), precipitation, temperature, vegetation, soil, and distance from the river impact flood occurrences. This article will discuss the effect of each factor and how to map them.   <strong>Results and Discussion</strong> According to the values estimated by the model and the graphs drawn in Excel, it can be concluded that the AWBM model has a relative ability to estimate the runoff trend in the Kerganrood watershed. The model attempts to replicate the highest river discharge points during the designated time series. Although it follows a uniform mode in simulation, it can compute the runoff flow process similar to reality. Therefore, the use of this model has been evaluated with average accuracy in monthly simulation and has obtained the required efficiency satisfactorily. In this model, the runoff graph shows an increasing trend over time in 2011, 2014, 2017 and 2018, which indicates the risk of flooding in the study area based on the floods recorded by the Water and Regional Organization of Gilan Province. This increasing trend and the peak of the river flow correspond to the floods of September and October 2011, 2014, 2017 and October 5, 2018, which caused significant damage to the area's residents. In the spatial zoning of flood risk, the average data of Talesh synoptic station and 9 hydrometric stations recorded by the hydrometeorological and hydrological organization of Gilan province and Ardabil province were used to draw the map of the distribution of precipitation and temperature in the Kerganrood watershed. In the next step, the slope, slope direction, and topographic map were drawn using the digital elevation model (DEM) in the GIS software environment with a spatial resolution of 12.5 meters. Then, the waterways of the Karganrood basin have been classified after estimation by calculating the Euclidean distance from the river. In drawing the geological map, the 1:100,000 geological map of Talesh city was used, and for drawing the soil map, the soil map of the whole of Iran was used. Finally, to draw land use and vegetation maps, Landsat satellite images have been used as inputs for spatial zoning of flood risk. First, experts' opinions are used to weight indicators through network analysis in Super Decisions software. Then, layers are classified using GIS software, and a flood risk zoning map is created through the Weighted Overlay and Raster Calculate tools. In the end, an output map was extracted as a spatial flood zoning map of the Kerganrood Talesh basin with very low, low, medium, high, and very high-risk points, and the area of each floor was calculated.   <strong>Conclusion</strong> The spatial zoning of flood risk in the Karganrood Talesh watershed was done using AWBM and Fuzzy-ANP models. The Nash-Sutcliffe coefficient was 0.553 and 0.507 in the calibration and validation stages, respectively, based on the AWBM outputs. The estimated results have been evaluated as acceptable and show that in terms of time zoning, the trend of runoff in the years 2011, 2014, 2017 and 2018 is increasing and is in accordance with the floods that occurred in reality in the mentioned years. In the spatial zoning of flood risk using the fuzzy-ANP method, precipitation factors with 0.299856 and distance from the river with 0.150357 have the most significant impact compared to other factors about flood risk. However, the temperature factor with 0.0265413 has also obtained the least importance in causing floods in the studied basin. In the upper regions of the basin, the risk of flooding decreases as the height increases due to dense vegetation and resistant soil. 31.63% of the basin has very low flood risk, while 90.3% has a very high risk based on classification criteria. According to the results, it can be said that by taking appropriate measures and planning, the damage caused by floods in the studied area can be reduced as much as possible.   <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work.   <strong>Conflict of Interest</strong> Authors declared no conflict of interest.   <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. <strong>ABSTRACT</strong> Evaluating the flood potential of different watersheds is one of the important measures in the field of reducing damages caused by floods. As one of the flood-prone basins of Gilan province, the River catchment has always caused a lot of damage to the residents of the region in recent years. Therefore, due to the lack of studies in this basin, the current research has attempted to zonate the risk of flooding, and for this purpose, the AWBM model and the Fuzzy-ANP method have been used. , 2014, 2017 and the end of 2018 are estimated to increase and equal to the floods of 1990, 1993, 199, and 1997. In the spatial zoning of flood risk, 10 effective factors incluincludingecipitation, temperature, distance from the river, slope, slope direction, height, land use, vegetation, geolo   and soil were used. In the analysis of the results, it is estimated that the highest risk of flooding is in the southern areas and the outlet of the basin to the Caspian Sea, and the settlement in the river, lack of attention to watershed management, destruction of forests and pastures, and land use change are among the most important factors affecting this issue. In total, 90.3% of the area of the basin has the highest risk of flooding from a geographical point of view <strong>Extended Abstract</strong> <strong>Introduction</strong> Each of the effective factors in causing floods has a different contribution to the risk of its occurrence at the level of catchment basins so that each can be prioritized according to its importance in the region. Reclamation of watersheds for flood control in one project is impractical due to its large size, expansion of impervious areas, and economic and operational issues that can increase flooding. The temporal or spatial zoning of flood risk in this area has not been done with any of the selected models, and the relevant authorities rarely take measures to reduce flood damage. More research is needed in this field to study the basin properly. This study was conducted with the aim of flood risk zoning using two AWBM and Fuzzy-ANP models.   <strong>Methodology </strong> Monthly evapotranspiration, river flow, and precipitation data from 2006 to 2018 were used to simulate the runoff volume of Kerganrood Talesh River using the AWBM model for time zoning. The research used data from synoptic and hydrometric stations in Hashtpar, Lisar, Mashinkhaneh, Sheikh Darun Shandol, Kishli, Khan Balaghi, Piseson, and Davor Ardabil, prepared by the synoptic and Hydrometrical stations of Gilan and Ardabil Provinces. The required data is first arranged in Excel, in the format of RRL software, then it is defined for the model, and based on 9 parameters determined by the software itself, the simulation has been done to estimate the runoff and flood of this basin. This method evaluates the model's accuracy in simulating the observational data using the Nash-Sutcliffe coefficient index (EN2) as the objective function and the explanation coefficient (R2). Additionally, the sensitivity level of the parameters used in the model is investigated in the studied area. In order to conduct spatial zoning, Cochran's formula was used to calculate the statistical sample size. Then, 30 questionnaires were distributed among experts in the field based on the research objective. The purpose, criteria, and sub-criteria of the Super Decision software were determined, and 10 indicators were selected, which are factors such as geology, slope, land use, digital elevation model (DEM), precipitation, temperature, vegetation, soil, and distance from the river impact flood occurrences. This article will discuss the effect of each factor and how to map them.   <strong>Results and Discussion</strong> According to the values estimated by the model and the graphs drawn in Excel, it can be concluded that the AWBM model has a relative ability to estimate the runoff trend in the Kerganrood watershed. The model attempts to replicate the highest river discharge points during the designated time series. Although it follows a uniform mode in simulation, it can compute the runoff flow process similar to reality. Therefore, the use of this model has been evaluated with average accuracy in monthly simulation and has obtained the required efficiency satisfactorily. In this model, the runoff graph shows an increasing trend over time in 2011, 2014, 2017 and 2018, which indicates the risk of flooding in the study area based on the floods recorded by the Water and Regional Organization of Gilan Province. This increasing trend and the peak of the river flow correspond to the floods of September and October 2011, 2014, 2017 and October 5, 2018, which caused significant damage to the area's residents. In the spatial zoning of flood risk, the average data of Talesh synoptic station and 9 hydrometric stations recorded by the hydrometeorological and hydrological organization of Gilan province and Ardabil province were used to draw the map of the distribution of precipitation and temperature in the Kerganrood watershed. In the next step, the slope, slope direction, and topographic map were drawn using the digital elevation model (DEM) in the GIS software environment with a spatial resolution of 12.5 meters. Then, the waterways of the Karganrood basin have been classified after estimation by calculating the Euclidean distance from the river. In drawing the geological map, the 1:100,000 geological map of Talesh city was used, and for drawing the soil map, the soil map of the whole of Iran was used. Finally, to draw land use and vegetation maps, Landsat satellite images have been used as inputs for spatial zoning of flood risk. First, experts' opinions are used to weight indicators through network analysis in Super Decisions software. Then, layers are classified using GIS software, and a flood risk zoning map is created through the Weighted Overlay and Raster Calculate tools. In the end, an output map was extracted as a spatial flood zoning map of the Kerganrood Talesh basin with very low, low, medium, high, and very high-risk points, and the area of each floor was calculated.   <strong>Conclusion</strong> The spatial zoning of flood risk in the Karganrood Talesh watershed was done using AWBM and Fuzzy-ANP models. The Nash-Sutcliffe coefficient was 0.553 and 0.507 in the calibration and validation stages, respectively, based on the AWBM outputs. The estimated results have been evaluated as acceptable and show that in terms of time zoning, the trend of runoff in the years 2011, 2014, 2017 and 2018 is increasing and is in accordance with the floods that occurred in reality in the mentioned years. In the spatial zoning of flood risk using the fuzzy-ANP method, precipitation factors with 0.299856 and distance from the river with 0.150357 have the most significant impact compared to other factors about flood risk. However, the temperature factor with 0.0265413 has also obtained the least importance in causing floods in the studied basin. In the upper regions of the basin, the risk of flooding decreases as the height increases due to dense vegetation and resistant soil. 31.63% of the basin has very low flood risk, while 90.3% has a very high risk based on classification criteria. According to the results, it can be said that by taking appropriate measures and planning, the damage caused by floods in the studied area can be reduced as much as possible.   <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work.   <strong>Conflict of Interest</strong> Authors declared no conflict of interest.   <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. https://jphgr.ut.ac.ir/article_94291_850415fd805f11a067e131d82df6142c.pdf

University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 02 Erosion modeling of Jajrud river banks Between Letyan and Mamlu dams Jajrud, Tehran Erosion modeling of Jajrud river banks Between Letyan and Mamlu dams Jajrud, Tehran 89 109 93008 10.22059/jphgr.2023.358931.1007770 FA Ali Golestani Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Mohammad Mehdi Hosseinzadeh Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Journal Article 2023 05 23 <strong>ABSTRACT</strong> Rivers in their path are always struggling with a phenomenon called erosion, which on the one hand causes many changes in the geometric shape of the river section, morphology and hydraulic characteristics of its flow, and on the other hand, it brings irreparable effects to the lands adjacent to the channel. One of the main sources of sediment production is the erosion of river banks. In this regard, investigating the amount of coastal erosion is one of the management strategies. The area under study is the banks of the Jajroud River, between Letian Dam and Mamlo Dam, with a total of seven sections. In this study, for the erosion of the river bank and estimation of the amount of sediment from the method or model of estimation of the bank and foot of the bank (BSTEM) in this model, the geometrical parameters of the channel (angle of the wall and height of the bank and the distance of the toe of the bank and its angle), the height of the layers And their species, flow information and vegetation cover and other side cover materials have been extracted and used. In this research, the depth of the flow in a spiral discharge mode and the flow duration of 12 hours were used to model the bank erosion. The model models the amount of bank destruction by calculating the shear stress and soil resistance. The results of the research showed that all sections except section 6 have high erosion. The difference in erosion values in different stages was mostly due to the type of bank sediments and bank slope angle. In terms of bank stability and safety factor (FS), the most unstable bank was in section 5 and the most stable bank was in section 6 of the river   Extended Abstract Introduction Rivers always struggle with a phenomenon called erosion on the one hand, it makes many changes in the geometric shape of the river section, morphology, and hydraulic characteristics of its flow, and on the other hand, it brings irreparable effects to the lands adjacent to the channel. There are different types of erosion phenomena, one of the most important and common erosion mechanisms in rivers is the mass erosion of river banks. extensive research has been done in the field of mass erosion and factors affecting it that lead to soil erosion and loss of land adjacent to the river one of the main sources of sediment production is the erosion of river banks. There are various methods and models to estimate the amount of river bank erosion, and the Bank Stability and Toe Erosion Model (BSTEM) is one of the numerical simulation models. This model has been developed to predicting lateral retreat streambanks (caused by river erosion and geotechnical rupture). This model estimates the erosion rate by taking into account the soil resistance forces and driving forces along the surface prone to failure (rupture).   Methodology This study was carried out between the Letyan and Mamlu dams in the Jajrud River in the east of Tehran city. The effects of erosion are evident along the entire length of the channel despite the dam and its controlling role. The maximum discharge of Letyan dam was 206 cubic meters per second in the water year 1994-95, and its average discharge was recorded as 1.67 cubic meters per second in the statistical period from 1988 to 2018. In this research, the cross-sections under study were selected, based on aerial photos and satellite images and then based on field visits, the selected sections (seven sections) were examined to study bank erosion by BSTEM model. The BSTEM model is one of the most widely used and advanced models regarding the stability of the river bank. This model was developed by the National Sediment Laboratory in Oxford-Mississippi in the United States. This model estimates the erosion rate by considering the soil resistance forces and driving forces along the failure-prone surface. The required parameters of the model include the following 1- Geometric parameters of the channel 2- The thickness of the layers and their materials 3- flow data (flow rate) 4- Vegetation and other side covering materials. After entering the mentioned data into the model, can be seen bank erosion modeling (bank geometry, angle, and height of failure surface occurrence) and bank toe erosion modeling, for specific flow periods. The bank safety factor (FS) is calculated at the end of the modeling. In this section, you can see the results of the model, including the calculated shear stress, the amount of bank retreat, the amount of sediments transported from the bank and the bank toe, the new profile of the bank, and the amount of erosion.   Results and Discussion In this research, the bank erosion has been simulated in the BSTEM model to investigate the amount of bank retreat and the amount of sediment produced in 7 cross-sections of the Jajrud River. This research was used the scenario of flow depth in the case of bankfull and 12-hour flow duration to simulate the bank and the bank toe. Based on the simulation results, the amount of hydraulic erosion and the change in the geometry of the bank toe should be determined. The amount of erosion for the cross-sections was as follows. cross-section 1 is 21m^3, back length is 0.57 m and safety factor is 0.38, cross-section 2 is 4 m^3, back length is 0.63 m and safety factor is 0.05, cross-section 3 is m^3, back length is 0.57 m and Safety factor 0.69, cross-section 4 6 m^3, rear length 0.66 m and safety factor 0.66, cross-section 5 is 21 m^3, rear length 1.28 m and safety factor 1.3, cross-section 6 is m^3, Back length - m and safety factor 3.34, cross-section 7 is 9 m^3, back length 0.65 m and safety factor 0.82. This model was carried to know the bank erosion and the amount of sediment production due to bank failure and erosion of the channel bank in seven cross-sections of the channel and the results of all sections except cross-section 6 show high erosion. In cross-section 6, the top of the wall was in a low-risk state, and the foot of the wall brought an acceptable amount of sediment into the channel. The bank angle is most important and effective parameter.   Conclusion In all cross-sections, there is a large amount of retreat, the highest of which was related to cross-section 5 with an amount of 1.28 meters, and the lowest was related to cross-section 6 (almost zero). Other cross-sections are in the range of 57 cm to 66 cm. In terms of bank stability and safety factor (FS), the most unsafe cross-section is number 5 to the amount of 0.05 and the safest section is number 6 to the amount of 3.34. Of course, the safety number of 1.3 for cross-section 5 with the condition of vegetation is also high safety. The highest weight of the fallen mass is for cross-sections 5, 1, and 7, respectively and after these sections, there is cross-section number 4 and cross-section number 2. Field observations after one year showed that results of cross-sections No. 2, 3, and 4 are very close to reality and the walls have collapsed, which shows the high compatibility of this model with the natural conditions of the region. <strong> </strong> <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work.   <strong>Conflict of Interest</strong> Authors declared no conflict of interest.   <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. <strong>ABSTRACT</strong> Rivers in their path are always struggling with a phenomenon called erosion, which on the one hand causes many changes in the geometric shape of the river section, morphology and hydraulic characteristics of its flow, and on the other hand, it brings irreparable effects to the lands adjacent to the channel. One of the main sources of sediment production is the erosion of river banks. In this regard, investigating the amount of coastal erosion is one of the management strategies. The area under study is the banks of the Jajroud River, between Letian Dam and Mamlo Dam, with a total of seven sections. In this study, for the erosion of the river bank and estimation of the amount of sediment from the method or model of estimation of the bank and foot of the bank (BSTEM) in this model, the geometrical parameters of the channel (angle of the wall and height of the bank and the distance of the toe of the bank and its angle), the height of the layers And their species, flow information and vegetation cover and other side cover materials have been extracted and used. In this research, the depth of the flow in a spiral discharge mode and the flow duration of 12 hours were used to model the bank erosion. The model models the amount of bank destruction by calculating the shear stress and soil resistance. The results of the research showed that all sections except section 6 have high erosion. The difference in erosion values in different stages was mostly due to the type of bank sediments and bank slope angle. In terms of bank stability and safety factor (FS), the most unstable bank was in section 5 and the most stable bank was in section 6 of the river   Extended Abstract Introduction Rivers always struggle with a phenomenon called erosion on the one hand, it makes many changes in the geometric shape of the river section, morphology, and hydraulic characteristics of its flow, and on the other hand, it brings irreparable effects to the lands adjacent to the channel. There are different types of erosion phenomena, one of the most important and common erosion mechanisms in rivers is the mass erosion of river banks. extensive research has been done in the field of mass erosion and factors affecting it that lead to soil erosion and loss of land adjacent to the river one of the main sources of sediment production is the erosion of river banks. There are various methods and models to estimate the amount of river bank erosion, and the Bank Stability and Toe Erosion Model (BSTEM) is one of the numerical simulation models. This model has been developed to predicting lateral retreat streambanks (caused by river erosion and geotechnical rupture). This model estimates the erosion rate by taking into account the soil resistance forces and driving forces along the surface prone to failure (rupture).   Methodology This study was carried out between the Letyan and Mamlu dams in the Jajrud River in the east of Tehran city. The effects of erosion are evident along the entire length of the channel despite the dam and its controlling role. The maximum discharge of Letyan dam was 206 cubic meters per second in the water year 1994-95, and its average discharge was recorded as 1.67 cubic meters per second in the statistical period from 1988 to 2018. In this research, the cross-sections under study were selected, based on aerial photos and satellite images and then based on field visits, the selected sections (seven sections) were examined to study bank erosion by BSTEM model. The BSTEM model is one of the most widely used and advanced models regarding the stability of the river bank. This model was developed by the National Sediment Laboratory in Oxford-Mississippi in the United States. This model estimates the erosion rate by considering the soil resistance forces and driving forces along the failure-prone surface. The required parameters of the model include the following 1- Geometric parameters of the channel 2- The thickness of the layers and their materials 3- flow data (flow rate) 4- Vegetation and other side covering materials. After entering the mentioned data into the model, can be seen bank erosion modeling (bank geometry, angle, and height of failure surface occurrence) and bank toe erosion modeling, for specific flow periods. The bank safety factor (FS) is calculated at the end of the modeling. In this section, you can see the results of the model, including the calculated shear stress, the amount of bank retreat, the amount of sediments transported from the bank and the bank toe, the new profile of the bank, and the amount of erosion.   Results and Discussion In this research, the bank erosion has been simulated in the BSTEM model to investigate the amount of bank retreat and the amount of sediment produced in 7 cross-sections of the Jajrud River. This research was used the scenario of flow depth in the case of bankfull and 12-hour flow duration to simulate the bank and the bank toe. Based on the simulation results, the amount of hydraulic erosion and the change in the geometry of the bank toe should be determined. The amount of erosion for the cross-sections was as follows. cross-section 1 is 21m^3, back length is 0.57 m and safety factor is 0.38, cross-section 2 is 4 m^3, back length is 0.63 m and safety factor is 0.05, cross-section 3 is m^3, back length is 0.57 m and Safety factor 0.69, cross-section 4 6 m^3, rear length 0.66 m and safety factor 0.66, cross-section 5 is 21 m^3, rear length 1.28 m and safety factor 1.3, cross-section 6 is m^3, Back length - m and safety factor 3.34, cross-section 7 is 9 m^3, back length 0.65 m and safety factor 0.82. This model was carried to know the bank erosion and the amount of sediment production due to bank failure and erosion of the channel bank in seven cross-sections of the channel and the results of all sections except cross-section 6 show high erosion. In cross-section 6, the top of the wall was in a low-risk state, and the foot of the wall brought an acceptable amount of sediment into the channel. The bank angle is most important and effective parameter.   Conclusion In all cross-sections, there is a large amount of retreat, the highest of which was related to cross-section 5 with an amount of 1.28 meters, and the lowest was related to cross-section 6 (almost zero). Other cross-sections are in the range of 57 cm to 66 cm. In terms of bank stability and safety factor (FS), the most unsafe cross-section is number 5 to the amount of 0.05 and the safest section is number 6 to the amount of 3.34. Of course, the safety number of 1.3 for cross-section 5 with the condition of vegetation is also high safety. The highest weight of the fallen mass is for cross-sections 5, 1, and 7, respectively and after these sections, there is cross-section number 4 and cross-section number 2. Field observations after one year showed that results of cross-sections No. 2, 3, and 4 are very close to reality and the walls have collapsed, which shows the high compatibility of this model with the natural conditions of the region. <strong> </strong> <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work.   <strong>Conflict of Interest</strong> Authors declared no conflict of interest.   <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper. https://jphgr.ut.ac.ir/article_93008_4d7c5ecf2800c2c0ac447f8925829b8c.pdf

University of Tehran Physical Geography Research 2008-630X 55 3 2023 11 02 Rapid assessment approach of Zarivar international wetland ecosystem services in Marivan County Rapid assessment approach of Zarivar international wetland ecosystem services in Marivan County 111 130 94851 10.22059/jphgr.2023.354474.1007743 FA Karwan Shanazi Department of Agricultural Extension and Education, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Mousa Aazami , Department of Agricultural Extension and Education, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Journal Article 2023 05 23 <strong> ABSTRACT</strong> Recognition and evaluation of wetland ecosystem services and ecological coherence can be effective in the supply and sustainability of services at different levels. In this regard, the current research has evaluated the ecosystem services of Zarivar wetland by using the rapid assessment ecosystem services approach and the millennium ecosystem services assessment framework for the sustainability and development of its services. In order to evaluate the services in four categories of provisioning, regulating, cultural, and support services, the rapid evaluation approach of Ramsar Convention services was used. Data collection was based on interview tools and questionnaires from local experts, experts from wetland-related institutions, and members of environmental associations in the region, 55 of whom were purposefully selected. The Ecosystem Service Index (ESI) was used to compare and score the importance of services. The results showed the positive potential of Zarivar wetland in all 4 categories of services, such that cultural services have the highest positive potential (ESI=0.66) and supporting services (ESI=0.57), regulating services (ESI=0.42) and provisioning services (ESI=0.38) were in the next place. The comparison of services provided at different levels showed that most services were reported locally. The correlation test showed a positive and significant relationship between different wetland ecosystem services, which causes synergy between its services. The results of applying the rapid assessment approach can be used in local and national policy frameworks and decision-making processes <strong>Extended Abstract</strong> <strong>Introduction</strong> Recognizing and evaluating wetland ecosystem services, their effective management of human and natural threats, and the ecological integrity of the wetland are crucial in the supply and sustainability of services at the local, regional, and even global levels. Wetlands are among the most productive and valuable ecosystems in the world, providing a wide range of economic, social, environmental, and cultural benefits currently classified as ecosystem services. Despite the apparent importance of wetlands, their value is routinely overlooked, and they are often suffering from poor decision-making, leading to the ongoing loss and degradation of wetlands and their services. An appropriate approach to prevent this inefficiency is intensely identifying and valuing the ecosystem services wetlands provide for the region. In this regard, the rapid assessment approach to support wetland ecosystem services was developed by identifying the practical time and resource constraints faced by operational staff and providing a simple, user-friendly, and cost-effective approach to support the systemic assessment of the full range of wetland ecosystem services. The conceptual framework of this approach assumes a dynamic interaction between people and ecosystems that changes in human conditions directly and indirectly cause changes in ecosystems, and changes in ecosystems cause changes in human well-being. An overview of related literature reveals that there are very few studies aiming to provide a methodology and an approach for integrating ecosystem services into the framework of evaluation and management of wetland ecosystems, and the focus of studies on the biophysical processes of wetlands has been more than the evaluation of ecosystem services. Therefore, the current research aims to identify and evaluate the importance of Zarivar wetland services as an international and unique wetland located in the west of Iran with the approach of rapid assessment of ecosystem services to protect and develop ecosystem services and to present practical recommendations dealing with challenges of its ecosystem services. Methodology In order to evaluate Zarivar wetland ecosystem services from the respondents' point of view, ecosystem service indicators were taken from the framework of evaluation of Millennium ecosystem services (2003) and Ramsar Convention (2018) in four axes, including regulating, provisioning, cultural and support sectors and the approach of rapid assessment of wetland ecosystem services. It was applied through interviews with key participants in the region. These participants consisted of selected informants from among the local leaders living in the villages on the edge of the wetland (30 people), members of the environmental associations of the Zarivar wetland (Green Chia Association and Zhivan Association) (11 people), official experts from government institutions involved in management Zarivar Wetland (14 people), and some purposefully selected local people (55 people). The list of ecosystem services in this approach was modified and adapted according to the local context through dialogue and consultation with local stakeholders who were deeply familiar with the wetland. The exact scope of the evaluated area was defined objectively by the expert evaluator based on the purpose or scope of the evaluation, which in this study was the watershed area of Zarivar wetland and the area of its wildlife refuge. A checklist of services grouped into functional categories was originally defined in the Millennium Ecosystem Assessment and was set as an initial structural framework. In the next step, the semi-quantitative importance of each service was scored on a scale from "significantly positive" (++) to "neutral" (0) to "significantly negative" (--), as indicated. Equation (1) was used to derive the index of comparable ecosystem services; the range of ESI is from +1 to -1, calculated for each of the four categories of ecosystem services or a combined value for all services. Positive scores and close to one indicate the significant potential and importance of the wetland in providing the desired service, and negative scores and close to one indicate the negative potential of the wetland in that service. A score of zero indicates the wetland's unimportance and lack of potential in terms of the intended service. Finally, the collected data was analyzed using spss25 and Excel software.  Equation (1) ESI= <strong> </strong> <strong>Results and discussion</strong> The study's results showed the positive potential of wetlands in all four intended categories of services, which indicates the potential for positive contributions of wetlands to human well-being. Perhaps the most important services provided by the wetland, from the respondents' point of were cultural services with an ecosystem service index (ESI = 0.66), supporting services with an ecosystem service index (ESI = 0.57), and regulating services with an ecosystem service index (ESI= 0.42) and provisioning services with ecosystem service index (ESI = 0.38). The findings of the contribution of Zarivar wetland ecosystem services at the local, regional, and global levels showed that 34 of the 36 classified services are provided locally and support most wetland residents. Zarivar has also provided 10 services at the regional level, 5 of which are in the regulating dimension (regulating air quality, pollination, reducing the risk of floods and storms, and purifying outgoing water), three services in the cultural dimension (cultural heritage, tourism, and recreation, education, and research) and two cases in the provisioning dimension (genetic resources and medicinal plants). According to the acquired results, at the global level, Zarivar has provided five important services as protection of genetic resources, global climate regulation with carbon storage and sequestration, tourism and recreation, education and research, and habitat provision for biodiversity and protection of rare species. The results of the applied correlation test between Zarivar wetland ecosystem services show a positive and significant correlation between all five main services (sig= 99% level). In other words, it can be concluded that there is a kind of convergence between Zarivar wetland ecosystem services, which will change with tangible changes in each service. In the meantime, support services are highly correlated with other services. Some management strategies seem to weaken the provision of valuable services in this area. <strong> </strong> <strong>Conclusion</strong> The comprehensive management and integrated planning of wetlands with emphasis on good governance is necessary to develop the participation and accountability of various stakeholders and achieve win-win goals. Finally, some increasing economic development activities and goals should be targeted by recognizing the value of sustainable use of ecosystem services and using payment methods for ecosystem services to maintain and sustain services.   <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work. <strong> </strong> <strong>Conflict of Interest</strong> Authors declared no conflict of interest. <strong> </strong> <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper.   <strong> ABSTRACT</strong> Recognition and evaluation of wetland ecosystem services and ecological coherence can be effective in the supply and sustainability of services at different levels. In this regard, the current research has evaluated the ecosystem services of Zarivar wetland by using the rapid assessment ecosystem services approach and the millennium ecosystem services assessment framework for the sustainability and development of its services. In order to evaluate the services in four categories of provisioning, regulating, cultural, and support services, the rapid evaluation approach of Ramsar Convention services was used. Data collection was based on interview tools and questionnaires from local experts, experts from wetland-related institutions, and members of environmental associations in the region, 55 of whom were purposefully selected. The Ecosystem Service Index (ESI) was used to compare and score the importance of services. The results showed the positive potential of Zarivar wetland in all 4 categories of services, such that cultural services have the highest positive potential (ESI=0.66) and supporting services (ESI=0.57), regulating services (ESI=0.42) and provisioning services (ESI=0.38) were in the next place. The comparison of services provided at different levels showed that most services were reported locally. The correlation test showed a positive and significant relationship between different wetland ecosystem services, which causes synergy between its services. The results of applying the rapid assessment approach can be used in local and national policy frameworks and decision-making processes <strong>Extended Abstract</strong> <strong>Introduction</strong> Recognizing and evaluating wetland ecosystem services, their effective management of human and natural threats, and the ecological integrity of the wetland are crucial in the supply and sustainability of services at the local, regional, and even global levels. Wetlands are among the most productive and valuable ecosystems in the world, providing a wide range of economic, social, environmental, and cultural benefits currently classified as ecosystem services. Despite the apparent importance of wetlands, their value is routinely overlooked, and they are often suffering from poor decision-making, leading to the ongoing loss and degradation of wetlands and their services. An appropriate approach to prevent this inefficiency is intensely identifying and valuing the ecosystem services wetlands provide for the region. In this regard, the rapid assessment approach to support wetland ecosystem services was developed by identifying the practical time and resource constraints faced by operational staff and providing a simple, user-friendly, and cost-effective approach to support the systemic assessment of the full range of wetland ecosystem services. The conceptual framework of this approach assumes a dynamic interaction between people and ecosystems that changes in human conditions directly and indirectly cause changes in ecosystems, and changes in ecosystems cause changes in human well-being. An overview of related literature reveals that there are very few studies aiming to provide a methodology and an approach for integrating ecosystem services into the framework of evaluation and management of wetland ecosystems, and the focus of studies on the biophysical processes of wetlands has been more than the evaluation of ecosystem services. Therefore, the current research aims to identify and evaluate the importance of Zarivar wetland services as an international and unique wetland located in the west of Iran with the approach of rapid assessment of ecosystem services to protect and develop ecosystem services and to present practical recommendations dealing with challenges of its ecosystem services. Methodology In order to evaluate Zarivar wetland ecosystem services from the respondents' point of view, ecosystem service indicators were taken from the framework of evaluation of Millennium ecosystem services (2003) and Ramsar Convention (2018) in four axes, including regulating, provisioning, cultural and support sectors and the approach of rapid assessment of wetland ecosystem services. It was applied through interviews with key participants in the region. These participants consisted of selected informants from among the local leaders living in the villages on the edge of the wetland (30 people), members of the environmental associations of the Zarivar wetland (Green Chia Association and Zhivan Association) (11 people), official experts from government institutions involved in management Zarivar Wetland (14 people), and some purposefully selected local people (55 people). The list of ecosystem services in this approach was modified and adapted according to the local context through dialogue and consultation with local stakeholders who were deeply familiar with the wetland. The exact scope of the evaluated area was defined objectively by the expert evaluator based on the purpose or scope of the evaluation, which in this study was the watershed area of Zarivar wetland and the area of its wildlife refuge. A checklist of services grouped into functional categories was originally defined in the Millennium Ecosystem Assessment and was set as an initial structural framework. In the next step, the semi-quantitative importance of each service was scored on a scale from "significantly positive" (++) to "neutral" (0) to "significantly negative" (--), as indicated. Equation (1) was used to derive the index of comparable ecosystem services; the range of ESI is from +1 to -1, calculated for each of the four categories of ecosystem services or a combined value for all services. Positive scores and close to one indicate the significant potential and importance of the wetland in providing the desired service, and negative scores and close to one indicate the negative potential of the wetland in that service. A score of zero indicates the wetland's unimportance and lack of potential in terms of the intended service. Finally, the collected data was analyzed using spss25 and Excel software.  Equation (1) ESI= <strong> </strong> <strong>Results and discussion</strong> The study's results showed the positive potential of wetlands in all four intended categories of services, which indicates the potential for positive contributions of wetlands to human well-being. Perhaps the most important services provided by the wetland, from the respondents' point of were cultural services with an ecosystem service index (ESI = 0.66), supporting services with an ecosystem service index (ESI = 0.57), and regulating services with an ecosystem service index (ESI= 0.42) and provisioning services with ecosystem service index (ESI = 0.38). The findings of the contribution of Zarivar wetland ecosystem services at the local, regional, and global levels showed that 34 of the 36 classified services are provided locally and support most wetland residents. Zarivar has also provided 10 services at the regional level, 5 of which are in the regulating dimension (regulating air quality, pollination, reducing the risk of floods and storms, and purifying outgoing water), three services in the cultural dimension (cultural heritage, tourism, and recreation, education, and research) and two cases in the provisioning dimension (genetic resources and medicinal plants). According to the acquired results, at the global level, Zarivar has provided five important services as protection of genetic resources, global climate regulation with carbon storage and sequestration, tourism and recreation, education and research, and habitat provision for biodiversity and protection of rare species. The results of the applied correlation test between Zarivar wetland ecosystem services show a positive and significant correlation between all five main services (sig= 99% level). In other words, it can be concluded that there is a kind of convergence between Zarivar wetland ecosystem services, which will change with tangible changes in each service. In the meantime, support services are highly correlated with other services. Some management strategies seem to weaken the provision of valuable services in this area. <strong> </strong> <strong>Conclusion</strong> The comprehensive management and integrated planning of wetlands with emphasis on good governance is necessary to develop the participation and accountability of various stakeholders and achieve win-win goals. Finally, some increasing economic development activities and goals should be targeted by recognizing the value of sustainable use of ecosystem services and using payment methods for ecosystem services to maintain and sustain services.   <strong>Funding</strong> There is no funding support.   <strong>Authors’ Contribution</strong> All of the authors approved the content of the manuscript and agreed on all aspects of the work. <strong> </strong> <strong>Conflict of Interest</strong> Authors declared no conflict of interest. <strong> </strong> <strong>Acknowledgments</strong> We are grateful to all the scientific consultants of this paper.   https://jphgr.ut.ac.ir/article_94851_900102faee609003281a4cd8cee84e81.pdf