فصلنامه پژوهش های ژئومورفولوژی کمی
سال دوازدهم شماره 2 (پیاپی 46، پاییز 1402)

The diversities on the planet are divided into two categories: biodiversity and geodiversity, which have attracted a lot of attention today. It has been proven that geodiversity can be an important foundation for biodiversity, for this reason it has been the focus of different people and communities. Among them, geodiversity means natural variations related to geological, geomorphological, paleontological, mineral, tectonic, soil, topographic and hydrological factors. In fact, these are heritage items that should be geologically protected for today's societies and future generations. Geodiversity is evaluated with three qualitative, quantitative and qualitative-quantitative methods. Qualitative-quantitative methods are using a combination of quantitative data (such as digital models) and qualitative data (questionnaire); which has more reliable results in geodiversity evaluation. One of these quantitative-qualitative methods in the field of geodiversity assessment is the (GI) model, which was introduced by Betard & Peulvast (2021). which this research seeks to use in addition to using this index in one of the mountainous regions of Iran (Lorestan province), its geodiversity for the purposes of To evaluate geological protection and benefit from its geosystemic values and services.

The studied area is Lorestan province in the western plateau of Iran, where a part of the Zagros mountains passes through it. Lorestan province is located in three geological structural units: Sanandaj-Sirjan, high Zagros and folded Zagros.The soils of Lorestan province can be divided into 5 main categories based on the characteristics and factors that are effective and measurable in the formation and development of soils and their ability to grow and develop plants. In terms of geomorphology, this province has various forms. This research has used the index (GI), which is a quantitative-qualitative method and is compatible with the use of geographic information system (GIS) and questionnaires in order to evaluate the geodiversity of Lorestan province. Its sub-indexes are lithological diversity, geomorphological diversity, hydrogeological diversity and diversity of soil landscape units.

In our study area, the lithological diversity was first calculated without considering the erodibility, and in the next steps, the hydrological, soil and geomorphological landscape units were calculated. Then weights were assigned to each of the diversity indicators using the hierarchical analysis process (AHP) and the results obtained from the hierarchical analysis process showed that the indicators of geomorphological diversity, lithological diversity, hydrogeological diversity and diversity of units. The soil landscape had the highest score respectively. Then, each of the sub-indices of geodiversity was multiplied by its weights and finally the geodiversity assessment map of Lorestan province was created. (679% square kilometers) of the area of the province is in the very high geodiversity class (V5); These areas include: Shires Canyon, Sepidasht folds and Hogback Robat, oshtorankuh and North Poldakhtar protected area. Shires Canyon due to having various karst forms and lithological diversity, Sepidasht Heights due to lithological, hydrogeological and geomorphological diversity and diversity in alluvial and structural landforms, Oshtorankuh due to lithological, hydrogeological, soil landscape units and geomorphological and karst landforms and affected by the tectonic dynamics of the region and Melawi and Pol-e dokhtar region have the highest geodiversity due to lithological, hydrogeological and geomorphological variations.

Geodiversity evaluation indicators are divided into three categories: quantitative, qualitative and quantitative-qualitative. The output of the geodiversity evaluation index and its related sub-indices were divided into five classes based on natural breaks lines: very low (V1), low (V2), medium (V3), high (V4) and very high (V5). In order to evaluate the final geodiversity of Lorestan province, the weight of each criterion was calculated using expert opinion and the Analytical Hierarchy Process (AHP). Then, the information layers of each of the sub-indices related to lithological, geomorphological, hydrogeological and soil diversity were added together based on the weights and the geodiversity map of Lorestan province was created. Based on the weights received by each of the sub-indexes of geodiversity evaluation, geomorphological diversity and lithological diversity have obtained the highest points respectively, which indicates the high role of these two factors in the evaluation of geodiversity of a region. The results obtained from the geodiversity assessment show that 1% of the area of Lorestan province (679 square kilometers) is in the very high diversity class of geodiversity (V5); which include: Shires Canyon, Sepidasht fold complexes, Oshtorankuh protected area and north of Poldakhter city. Also, Sefid Kuh Khorramabad and Qali Kuh Aligodars are also in the high diversity class of Geodiversity (V4). The results of this research can be used by planners and managers for planning related to Geoconservation, benefiting from ecosystem and geosystem services and Geotourism.

Achieving environmental sustainability of the geographical area, requires planning principles defense, defensive positioning and enhance the security of sensitive sites and ease of movement. The knowledge and mastery of the capabilities and limitations of the geomorphological a particular area and its defense policies in times of crisis, will have an important role in the stability of a region.The issue of defense planning to reduce the vulnerability and increase the sustainability of the environment and facilitate crisis management and military actions against enemy threats, a process that is essential in the area of a country and its security.

South-East coast of the Islamic Republic of Iran (Makran coast), is one of the strategic areas. This area is only ocean beaches and in terms of defense and strategic planning is extremely important.Due to the sensitivity of the special position of this region, many threats in various areas, including most notably military threats (due to the presence of foreign troops) is expected for this region Therefore, in order to deal with these threats, compliance issues studied in the treatment of central coast region can be guarantee sustainable development and security.

One thing that plays a major role in the preparation of the defense, which is one of the most basic natural features of the natural environment geomorphological features of the area, which is the regional context of various activities in the area include. In this study, the preparation of the defense and security in South East Iran has been emphasizing the geomorphological features.This descriptive - field-based analysis methods and library. First, using GIS software to assess the ecological potential for human development activities, including urban development, rural industries And then to zoning and locating the region to military activities and defense were using AHP model and GIS software and then the complications are detected geomorphological area in preparation of an effective defense and a questionnaire survey of experts, the value and importance of each factor in the preparation of the defense review.

The various stages of the model was to be phased out and all the strengths, weaknesses, opportunities and threats were identified geomorphological region in terms of defense planning. The final factor 3/222 region's strengths, weaknesses final factor 2/859, 3/349 and regional opportunities final coefficient ratio was 3/011 final regional threats. The coefficients obtained from the matrix was placed strategically assess the situation and act according to the result, Strategies study area is close to an aggressive strategy and the authorities should try to advantage of strengths and opportunities, and to take steps towards this strategy.

As a morphological phenomenon, land subsidence is a type of change in the shape of the earth's surface, which is associated with a vertical deformation or downward movement of the earth's surface, as well as the gradual settlement or removal of surface materials. The phenomenon of subsidence is due to various causes, including natural factors such as earthquake, volcanoes, fault activities, subsidence due to rising sea levels, dissolution in rocks or following human activities, including; Indiscriminate removal of fluids from the ground, such as; Water, oil and gas occur. The environmental consequences of the subsidence phenomenon are irreversible, costly, and destructive, and include creating a gap on the surface of the earth, damaging human structures, etc. Foundations, streets, bridges, roads and power and sewage transmission lines, destruction of irrigation systems and fertile agricultural soils and damage to wells. According to the statistics announced in Iran, the adverse effects caused by subsidence are not low and are rapidly developing and spreading in different plains across the country, and the lack of timely management and control of its factors can cause loss of life. And leave an irreparable loss.

In this research, the images of Sentinel 1, which captures images in the C-band range of microwaves, have been used. Then the necessary processing was done through the SARSCAPE 5.2 plugin in ENVI 5.3 software and the technique used in this research to determine the amount of subsidence is the differential interferometric method with the combined opening of two frequent or non-frequent passes. In radar interferometry, the phase difference of two images from a specific time zone and baseline is determined. To zone the risk of subsidence, in the stage of data collection, the influencing components must first be specified and the required data and information must be collected and classified based on them. For this purpose, in this study, first, the effective factors (including slope, lithology, land use, precipitation, distance from the city and village, distance from the river, distance from the fault, and drop in the underground water level), according to the natural and human conditions of the region was identified. In the next step, information layers related to each of the factors were prepared in the geographic information system environment. In the next step, the weighting of the investigated factors was done according to the Critic method, and the final analysis was done using the Aras method.

After the interferometry steps, the phase difference has been converted into vertical displacement in the metric system. During the surveys conducted, the amount of subsidence between the years 2016 and 2020, during the last 5 years, shows that according to the above map, the highest amount of subsidence in the central, north-western, and north-eastern parts, amounting to 0.37 mm, it is concentrated. Investigation and analysis of land use and subsidence map and field studies confirm the maximum occurrence of subsidence in agricultural areas, and urban and rural areas, respectively. The presence of fertile plains and the flow of the Qarasu river in Namin city has provided a good opportunity for agricultural and animal husbandry activities, and the areas with agricultural land use have a high potential for subsidence due to the exploitation of underground water areas. After extracting the maps of each of the criteria and applying the relevant weights obtained by the Critic method and by implementing the different stages of the Aras technique, the maps of the subsidence risk zoning in 5 categories from very high to very low risk The risk is achieved. According to the result of using the Aras method, 168.01 square kilometers of the range area is in the very high-risk class and 222.31 square kilometers is in the high-risk class. Most of the high-risk and high-risk class in terms of the possibility of subsidence is located in the central and semi-western parts. Examining the high-risk and high-risk points introduced by the Aras algorithm shows; In terms of the criteria of land use, agricultural use, urban and industrial areas account for the largest percentage of the area of areas with very high and high risk. According to the land use map of the study area, a major part of the city's land has been allocated to agricultural use, which has caused overexploitation of the underground water table in recent years. In addition, a large part of the water needed for drinking and the industrial sector is also supplied from underground water sources, and this, in turn, is involved in the reduction of the water level and the increase in the risk of subsidence in the studied area.

The evaluation of the subsidence rate of the region shows that the highest subsidence rate was in the central, north-west, and north-east areas of the range and the results show that the trend of the groundwater level drop is consistent with the subsidence rate and in the areas where the water level drop is the highest. has existed, the amount of subsidence has also been higher. According to the results of subsidence risk zoning; The criteria of water level drop, and land use, respectively, with a weighting factor of 0.186 and 0.168, were assigned the most weight, and therefore, it can be said that the most important factor involved in increasing the amount and potential of subsidence in the study area of exploitation. It is a waste of underground water. Finally, it can be acknowledged that because land subsidence can cause irreparable financial and human losses, long-term solutions in the form of modifying water resources management methods and short-term solutions in the form of prevention From extraction of underground water tables, creating of underground dams to increase the water level, curbing surface water and implementing artificial feeding plans, confiscating unauthorized drilling equipment, preparing and installing smart meter devices, organizing drilling companies, strict control of water consumption and change The consumption pattern should be taken into consideration by relevant officials as well as residents.

Today, despite all the activities that have been done for the residents of mountainous areas, facing a phenomenon called avalanche in mountainous areas is still a normal thing. For years, the people of mountainous areas have to deal with this natural threat. The manner and place of residence and the type of construction, forestry and land use plans in recent decades have minimized the risk of avalanches in mountainous areas. During the occurrence of natural crises that are associated with social anomalies, an efficient management plan must be prepared and adjusted in advance to firstly identify high-risk areas and secondly, the shortest and most reliable ways to access the centers and the best decision can be made in setting up relief centers. In Iran, studies on the phenomenon of snow and snow avalanches are more limited than other studies. In this study, the Absafid waterfall area of Aligudarz has been investigated in order to prepare an avalanche zoning map and the factors affecting the occurrence of this hazard.

In this research, the input data to the model was prepared first. The input data included sampling points that were from avalanche prone areas (dependent variable of the model) which were identified in order to identify avalanche prone spots through field visits, local inquiries and using the information of natural resources experts in the region. Of the 4 sampling methods used, the first method is to select points that were in the area of rocky outcrops (model 1), the second method is to select points that have slopes of more than 45 degrees (model 2), the third method is to select random points in the areas of snow accumulation (model 3), The fourth method of selecting points in a grid with a regular distance of 150 meters from each other in the area of snow accumulation (model 4). And the independent variables of the model, which include indices (Slope, Aspect, LS , TWI , Wind effect, VRM , MBI , profile and general curvature , NDVI ) were used for modeling.

AUC index values for each of the 4 models, respectively, in training and test mode for: the first model) 0.808 and 0.75, the second model) 0.885 and 0.868, the third model) 0.875 and 0.881, the fourth model) 0.947 and 0.94 and the results show that all models are in the category of excellent models. The results of the Jackknife statistics analysis show that in model 1, NDVI and Slope indices have the greatest impact, model number 2 relates to Slope and TWI indices, model 3 relates to NDVI and Slope indices, and in model number 4, NDVI and Slope indices have had the greatest impact on the output of the model. The results of matching the zoning maps with each other and the percentage difference between the maps obtained from the 4 models show that the lowest matching rate among the above maps is the result of the comparison between model 1 and 2, which is 53% and also the highest The compliance rate is related to model 3 and 4, and their lack of compliance is 9%. Also, comparing the results with field observations shows that model number 3 has predicted the best result in identifying avalanche spots in the evaluated area.

In recent decades, the use of different modeling algorithms has been developed. On the other hand, in all data-driven models, in order to initially train the model, it is necessary to introduce the points related to the place of occurrence of the desired phenomenon. Therefore, the type of distribution of input data can influence the output maps. The most important goal of this research is to evaluate the type of input data introduced in a data-oriented method (based on Shannon entropy and logistic regression, Max.Ent) in preparing a snow avalanche risk zoning map in the limits of the White Water waterfall in Aliguderz city. In order to prepare an avalanche risk zoning map, 10 geomorphometric factors were used, and based on the field survey, the area of avalanche occurrence was identified in the region, and snow avalanche prone points were introduced to the model in four different ways. The results of prediction models' accuracy (AUC), determining the importance and degree of sensitivity of each of the criteria used showed that the accuracy of the predicted maps varied between 0.81 and 0.95. Also, from the results of the most effective environmental indicators in the output of each of the models, it was evident that, in general, the criteria related to vegetation and slope were given the most weight. The results of the spatial evaluation of the prepared maps indicate a difference of 53%-9% between the avalanche prone areas among the four introduced methods. In general, the northwest to southwest regions are the most sensitive to the onset of avalanches in the study area, and this issue is evident in almost all models.

Soil erosion in any place is affected by various factors, including natural features and human activities. Mediterranean rainfall system and high water erosion, large extent of soils and formations sensitive to erosion, poor natural vegetation in many regions of the country and uneven conditions are some of the important natural factors affecting soil erosion in Iran (Arab Khodri, 2014). So that about 125 million hectares out of 165 million hectares of the country's lands are exposed to water erosiondramatically. Therefore, the incoming blown sand is dropped close to the brink line. Gully erosion as one of type of water erosion is very severe in many areas specially in arid and semi-aird areas. Because in areas with low vegetation cover are mpre prone to the drops of rainfall with high intensity. There are many researches regarding this type of water loss that some of these researches focus on modelling and predicted the prone areas with stochastic model. Rangzen et al. (1401) in their research studied the prone areas to gully erosion using fuzzy membership function in the watershed of Mehr city, in the south of Fars province, they have determined prone areas to gully erosion using fuzzy membership function and hierarchical analysis model (AHP) in Mehr city, in the south of Fars province. The results of their investigation showed that the areas located in the center of the studied area (about 18%) are more sensitive to gullies erosion. They have used the ROC curve to validate the model, the AUC values near 85 indicate the high accuracy of the model for predicting areas prone to gully erosion in the watershed of Mehr city. In this study we have applied the CART model to predict the prone areas in Ljasouh watershed in South of Fasr province in Iran.

The study area isKhasuye watershed, with an area of 136,622 hectares, is located 337 km from Shiraz city in Fars province, Zarindasht city. In terms of the geographical location of this watershed between the longitudes of 54 degrees and 9 minutes to 54 degrees and 42 minutes east and the latitudes of 28 degrees and 18 minutes to 28 degrees and 39 minutes north, it occupies the northern strip of Zarindasht city.The average annual and monthly temperatures of this basin are 21.91 and 19.09 degrees Celsius, respectively. Also, the maximum and minimum average temperature of the basin is 33.09 and 9.78 degrees Celsius, respectively, corresponding to the months of July, the average annual rainfall of Khasouye station is 221.54 mm and its average height above sea level is about 1150 meters.For the applying the CART model by using the SPM (Salford Peredectie Modeler) software in research, in first step, the locations of the gullies were recorded using the Google Earth software and Global Positioning System (GPS) in the whole study area. The second step, out of 16 influencing variables in gully erosion, including topography-related indicators (height, slope, slope direction, slope length, flow strength, stream depth, topographic wetness and longitudinal curvature), normalized vegetation cover index (NDVI), land use, distance from roads, distance from rivers, geological map, rainfall, soil type and soil erodibility have been used. After assigning the values related to independent indicators to each of gullies area, modeling has been run to predict the prone gullies areas in the study area, in the SPM software environment using the CART model. The applied model has used 70% of the data as training data and 30% of the data as test data in the modeling process.

One of the main factors in modeling is checking the accuracy of model results, therefore we have used different stastical index to evaulte the accuracy of our result for each traing and testing data. Table No. 1 shows the CART model accuracy evaluation indices. According to this table, the correlation coefficient or R2 for training data is equal to 0.904 and for test data is equal to 0.845. Considering that (Chain et al., 1998) have defined three values of 0.19, 0.33 and 0.67, respectively, as the criterion value for weak, medium and strong values of the evaluation of the structural parts of the model by means of the R2 index (correlation coefficient). Therfore we can conclude that the model it has high accuracy in predicting the points prone to gully areas height parameter with R square of 0.915 and Std error of estimate of 0.133.In terms of the relative importance of each of the independent variables participating in the CART modeling process, respectively, the variables of height, amount of precipitation, distance from streams and land use have the highest value with values above 50%, and the variables of slope direction, Longitudinal curvature, topographic wettness have the lowest values.

As we have seen in the predicted map of gully erosion the most of these features occur in the flat area with low slope in the Khasouye basin. Due to rainfall or irregular irrigation of the adjacent lands, the water flows on the surface and finally reaches these flat areas. Usually, the amount of precipitation in high areas is higher than in flat and low-altitude areas, but all the precipitation that occurs in high areas is due to other factors such as topography, slope and the direction of the slope of the area, especially in the Khasouye watershed, where the high areas lack suitable vegetation. By applying the results obtained from the implemented statistical model and the geological maps of the Khosouye watershed, it was determined that the most gullies occurred in the places consisting of the Quaternary formation. Quaternary formation includes alluvial and sedimentary deposits and loess. Due to the high solubility of this type of formation, its sensitivity to water erosion and especially to ditch erosion is very high.

The changes in the river flow regime are the main factor in the stability of the river ecosystem and may change due to factors such as dam construction, water abstraction, flow diversion, and climate change. The hydrological regime of the river is the main driving force of ecosystem dynamics and river functioning. In addition, hydrological regimes play a major role in changing the structure and ecological processes of river ecosystems. On the other hand, the morphological characteristics are constantly changing over time as a dynamic system and these changes will be different due to changes in river flow and sediment transport capacity. The management of the watershed according to the distribution of the annual values of each of the 33 parameters of hydrological changes within the range of natural changes of the parameters is the basis of the range of variability approach. When the purpose of river flow change analysis is different between two time periods, the IHA software allows users to use RVA change methods to calculate indicators and compare results. The effective management of the river ecosystem requires the description of the parameters of the hydrological regime of the natural flow and the determination of the degree of changes in the flow rate of the regulated flow compared to the natural flow. Based on the literature review, the assessment of changes in the regime of rivers in mountainous areas requires comprehensive research. Khiavchai River of Meshgin shahr is a snow-fed rivers and a typical mountainous river, which has been selected as the study area. The purpose of this study is to investigate the changes in hydrological flow indicators in Khiavchai River, in this regard, long-term discharge data and range of variability (RVA) are used.

First, the changes in annual discharge statistics were evaluated in the periods of 1969 to 2019 and then the studied periods were analyzed based on the change point analysis software. The range of variability approach is a type of hydrologically-based methods for river flow analysis. In this regard, management goals should be determined based on available ecological information regarding the river flow regime. In the absence of appropriate ecological information, it is recommended that the standard deviation range can be considered as a default for the initial determination of targets. In other words, the normal values of each of the IHA parameters in the normal state should be considered within the range of standard deviation (± STD) from the average values, or the 25% and 75% quartiles should be considered as the lower and upper limits of the parameters, respectively. The results of the changes in five groups of parameters of hydrological changes (IHA) in the range of range of variability changes were obtained at the Pol-Soltani hydrometric station, Khiavchai River using IHA software. In this regard, hydrologic change indicators are calculated using Indicator of Hydrologic Alteration software and compared and analyzed in different periods.

The results showed that the annual runoff series changes in two consequent periods. The changes in the average discharge variables in different months in both study periods of the year have been decreasing and the rate of change of the index has been negative compared to the previous periods. The results showed that the low flow discharge minimum 1, 3, 7, 30 and 90 days decreased and decreased to zero in the third period compared to the second period, to a value of 0.01. The mean changes of the base flow index also showed a decrease from 0.02 to zero. It is worth noting that the base flow index can lead to the reduction of snow storage or the destruction of vegetation, and as a result, it is upstream of the study area. The increasing trend of low flow pulses and recession rate also decreases considerably.

As a concluding remark, the pattern of changes in river flow indicators based on the changes of hydrologic indices in both study periods had a similar trend, which indicates the decreasing trend of changes in river flow regime components, and these changes have occurred as a result of water abstraction and river flow diversion. Although a part of the changes in discharge values can be related to the change in hydroclimatic variables, but due to lack of sufficient studies on changes in climatic variables, it is not possible to draw a firm conclusion in this regard. Determining changes in climate generators for the river flow regime can be suggested as one of influencing factors in river behavior changes as well as better management of surface water

Changes in climatic variables affect the hydrology of basins. Evaluating the trend of seasonal changes in runoff is important in the water management of watersheds, especially when drought and flood hazards occur. This research studied the seasonal changes of Runuff under hydrological characteristics in Gharaghom Catchment located in northeastern Iran.

The Gharaghom Catchment is the sixth watershed of the country with 14 dub basins and is located in the northeastern part of Iran with an area of about 43925 square kilometers. The study area is located at latitudes between 36° 07΄ and 37° 41΄ North, and longitudes between 48° 51΄ and 61° 13΄ East on the border of Afghanistan.In this research, the hydrological status of the Gharaghum basin was investigated by estimating the runoff in its 14 sub-basins using the SCS-CN experimental model of the American Soil Conservation Organization. The maximum runoff flow was estimated using digital model data at a height of 30 meters, precipitation and temperature data of climatic stations, and network data of temperature and precipitation.

The assessment of physiographic indicators of the basin showed that in some sub-basins the ability to produce runoff was high and the analysis of the model results in runoff production showed that the spring season with 117 mm of rainfall in the sub-basin of Keshaf Rood with the largest area compared to other sub-basins can produce peak flow. It has up to 2379.3 cubic meters per second, and in general 88% of all spring rains turn into the runoff. The state of the soil hydrological group and permeability, vegetation cover, rainfall, and catchment area create different conditions for the potential of runoff production in different seasons. The summer season, with the lowest average rainfall of 6 mm can produce less runoff than other seasons due to the effects of the basin area. In the autumn season, due to the less vegetation and the increase in the amount of precipitation to 28.9 mm, the soil hydrological group had a greater effect on the runoff production than in other seasons, and as a result, 63% of the autumn precipitation was converted into the runoff. In the winter season, the average rainfall reached 71 mm, and 82% of the rainfall turned into the runoff. Of course, solid precipitations occur in the winter season and their melting at the end increases the ability to produce runoff in the winter.

The evaluation of the physiographic indicators of the basin showed that in some sub-basins the ability to produce runoff is high and the spring season with 117 mm of rain in the sub-basin of Keshafrood with the largest area compared to other sub-basins can produce a peak discharge of up to 2379.3 cubic meters per second, and in general 88% of all spring rains turn into the runoff. In the autumn season, due to the less vegetation and the increase in the amount of precipitation to 28.9 mm, the soil hydrological group had a greater effect on the runoff production than in other seasons, and as a result, 63% of the autumn precipitation was converted into the runoff. In the winter season, the average rainfall reached 71 mm, and 82% of the rainfall turned into runoff. In general, hydrological group C with low soil permeability and a high amount of CN causes significant runoff production potential in the spring season in this watershed and the management of surface water resources is essential.The lowest rainfall is for the summer season with 6 mm, of which 17% becomes runoff.Vegetation has reached its peak growth in this season and even with the effects of the soil hydrological group, the potential of runoff production is at the lowest possible level.In autumn, the amount of precipitation increases to 28.9 mm, and also the vegetation is less than in summer. The result of these changes is an increase in the peak discharge so that 63% of this season's rainfall turns into the runoff. Due to vegetation reduction in autumn, the effects of hydrological groups become more visible and increase the potential of runoff production in the sub-basins. The highest peak flow rate in the Kashf Rood sub-basin is estimated to be 396.6 cubic meters per second in the autumn season, and the lowest peak flow rate is estimated to be 26 cubic meters per second in the Sheikh Canal sub-basin. The winter cold turns precipitation into the snow, the vegetation is very weak and the effect of soil hydrological groups is more visible than in other seasons, the average seasonal precipitation reaches 71.7 mm. This causes the peak discharge to increase and the limiting factor of runoff production is precipitation in solid form. In the Gharaghom catchment area, snowmelt occurs at the end of the winter season, and due to the effect of other mentioned factors, 82% of the precipitation is converted into runoff and increasing the ability to produce runoff in the winter season. Therefore, based on the seasonal difference of runoff in the Gharaghom catchment and the significant amount of the peak discharge, the need to manage the flood risk in this basin seems necessary. Protecting the areas of the sub-basin, taking into account the existing hydrological situation, can prevent the wastage of surface runoff, and manage the runoff, It can lead to an increase in artificial nutrition with the penetration of runoff into the ground.

one of the methods for studying active tectonic movements is the use of Morpho tectonic information .in the study of active tectonic , tectonic geomorphology is very valuable which can determine the effect of active tectonic on the river. Iran is one of the active regions of the earth due to its location in the Alpine-Himalaya mountain belt. The Alborz orogenic belt is also a part of this region, and the location of the studied area in Western Alborz and Azerbaijan has caused this region to be affected by tectonic processes resulting from this collision. In this study, in order to evaluate the amount of recent tectonic activity, the number of 50 watersheds along with the longest possible route of their rivers were extracted in the ArcGIS 10.1 environment, and then the geomorphic indices of hierarchical anomaly (∆a), Branches (R), longitudinal gradient of the river (SL), shape of the drainage basin (Bs), were calculated in 50 drainage basins and finally, by combining the mentioned indices, using the relative active tectonic index (Iat), the extent of the case The study is classified into four categories of very high, high, medium and low tectonic activity. The Sangavard fault (Firouzabad-Mujdar), which is the main fault of the studied area, affects the studied area from the north to the south and causes very high tectonic activity, as well as the Andalibi and Niki faults in the east and the Sheikh fault. Janlu and Niakhrem near the south-western part and the Kalin-Qiya fault in the west have very high tectonic activity. Landslide evidence from field observations proves the results of four geomorphological indicators in the studied area.

In this study, using Arc GIS software and a digital elevation model of 30 meters using the Strahler method, watersheds were divided and extracted. Then, by using topographic maps on a scale of 1:25000 and geological maps on a scale of 1:100000 and aerial photos on a scale of 1:20000 and through the Arc GIS software, different application layers including waterways, basins, faults, lithology and lines height, was prepared, and finally, in order to carry out the present research in the area of Western Alborz and Azerbaijan, the studied area was divided into 50 basins and morphometric indicators including hierarchical anomaly (∆a), branches (R), longitudinal gradient of the river (SL) ) and the shape of the drainage basin (Bs) have been evaluated in order to investigate the tectonic activity of the region. And in the last stage, the geological units and the main structures of the region were investigated and analyzed with the results of measuring geomorphological indicators and field observations.

In order to determine the level of relative recent earth-building activity in the target area, 4 geomorphological indices were calculated in 50 sub-basins. In order to measure the hydrometric indices, waterways and drainage basins of the region were extracted using a digital height model with an accuracy of 30 meters. Then the hierarchical indices, branches, shape of the drainage basin and longitudinal gradient index of the river were calculated. A zoning map was prepared separately for each index in the study area. Hierarchical anomaly index (∆a) was classified into three categories (high activity, medium activity and low activity) in terms of tectonic activity and in total 30 basins out of 50 basins of the studied area had high and medium activity. 21 basins showed high activity. The branching index (R) was divided into 3 categories (high tectonic activity, medium tectonic activity and low tectonic activity) according to the calculations, and out of 50 basins of the studied area, 38 basins have high activity and It showed average. According to the obtained values and results, the drainage basin shape index (Bs) was classified into 3 classes (high tectonic activity, medium tectonic activity and low tectonic activity). Out of 50 sub-basins of the entire sub-basin area, 32 showed high and medium amount of geo-structural activity according to drainage basin shape index (Bs). Like other indicators, the longitudinal gradient index (SL) was classified into 3 classes, according to which the activity level of the faults was checked. From the total of 50 sub-basins of the studied area, according to the values obtained from the river longitudinal gradient index (SL), 29 sub-basins have high and medium activity. Finally, in order to classify the region based on relative geo-structural activity index (Iat), geomorphological indices of hierarchical anomaly (∆a), branching index (R), drainage basin shape index (Bs) and river longitudinal gradient index (SL) were classified into three categories in terms of geological activity based on the values they had, and for each basin, the values of geomorphological indices (S/n) were measured and divided into 4 categories of relative tectoniv activity. (Iat) were divided. Of the 50 sub-basins in the studied area, 31 have very high and high tectonic activity.

By examining and evaluating the values obtained from the morphometric indices and putting together all the results for each of the faults separately and matching the sub-basins located on the important faults of the studied range in all the indices. It was shown that in the results of all morphometric indices, the sub-basins where the active bergsels of the region were located had a high activity category. The tectonic evidences obtained from field observations also prove the recent tectonic activity of structures and faults in the region. tectonic evidences such as faulting and folding in Neogene and Quaternary units, displacement of Neogene units due to the activity of the aforementioned faults, thrusting of old units on young units are a strong evidence of the high activity of the structures related to the faults. The scope of the study is The existence of travertine mines along the Sheikh-Janlu fault and the existence of landforms such as alluvial barracks, the creation of triangular surfaces, the tilting of layers, the creation of gorges and the existence of V-shaped valleys are among the results. The results of the morphometric indicators confirm the recent topographical activity of the area.

Geomorphology studies the forms and processes of earth's surface reliefs and their changes over time. Obtaining information about landforms and mapping of them re considered not only as a basis for different types of geomorphological research, but also for landscape evaluation, suitability studies, erosion studies, hazard prediction and various fields of landscape and regional planning or land system inventories is essential. recognition and extracting of landforms using traditional methods is time-consuming, costly, and affected by opaque and often unrepeatable decisions of the interpreter. Consequently, to accurately describe the topographical structure, new spatial analysis procedures and models need to be developed. Accessibility of digital elevation models, software development and increasing computational power of computers provide geomorphologists with tools and opportunities which may revolutionize their discipline. Nowadays, the automatic recognition of landforms is regarded as one of the most important procedures to classify landforms and deepen the understanding on the morphology of the earth. The main purpose of the study is Automatic Classification of Landforms and separation of the landscape of the Northeast Slopes of Natanz and Kashan Karkas Heights into landform classes using two methods of classification of Terrain Attributes (TA) and Topographic Position Index (TPA).

 Case Study The Northeast Slopes of Natanz and Kashan Karkas Heights was selected as the case area in the current study. The geocoordinates of the area are between E 33° 25′ 51′′ to E 34° 11′ 16′′ and N 50° 54′ 19′′ to N 52° 9′ 49′′ based on the World Geodetic System 1984 (WGS84), with a total area of 4,739 km2.  Landform classification process using Terrain Attributes The purpose of many models for the recognition and classification of landforms is to determine the froms of the hillslope. Terrain attributes is also one of these models. Chabala et al. (2013) used this model for the first time to Landform classification for digital soil mapping in the Chongwe-Rufunsa area, Zambia. The selected attributes were elevation, slope, relief intensity, and curvature. Terrain attributes derived from a digital elevation model were overlaid using cell statistics to generate a landform map with five classes: (1) Hills (Summit), (2) Upper Terraces (Shoulder), (3) Plateau (Back Slope), (4) Foot Slope and (5) Lowlands (Toe Slope).Landform classification process using Topographic Position Index TPI is only one of a vast array of morphometric properties based on neighboring areas that can be useful in topographic and DEM analysis. The classification using TPI is the difference between elevation value on pixel and the average elevation of the neighboring pixels. Positive values mean that the analyzed pixel has values greater than the surrounding values, while negative indicates that it is smaller. TPI values near zero are either flat areas (where the slope is near zero) or areas of constant slope (where the slope of the point is significantly greater than zero). Using topographic position index (TPI), a landform classification map of the study area was generated. The classification has six classes: (1) Valleys, (2) Lower Slopes, (3) Gentle Slopes, (4) Steep Slopes, (5) Upper Slopes and (6) Ridges.

 Landform Generation using Terrain Attributes the landform map was generated by overlaying the reclassified grids representing relief intensity, curvature, elevation and slope. This was done using the cell statistics tool in ArcMap with the mean set as the overlay statistic. The results of the landform classification are shown The landform of the Upper Terraces (Shoulder) with an area of 1,810 km2., which covers about 38% of the studied area, is the dominant landform of the landscape of the study area. Landform Generation using Topographic Position Index Land Facet Corridor Extension introduced for ArcMap software was used to classify landform elements with TPI model. The Valleys landform with an area of 1872 square kilometers, equivalent to about 40% of the study area, is considered as the dominant landform of the study area.

This research aims to Landform Classification and Mapping of the Northeast Slopes of Natanz and Kashan Karkas Heights Using Terrain Attributes (TA) and Topographic Position Index (TPI) which Both methods depend on digital elevation models (DEMs). Considering that the Terrain Attributes model uses the four parameters of Height above mean sea level, Topographic Slop, Curvature and Relief Intensity as input for processing and classifying landforms, it can potentially have higher accuracy than the TPI model that only uses DEM to identify features.

Alluvial fans are important depositional landforms developed around salt diapirs in the Zagros mountains. During time, some surfaces with different ages such as relict, old and young surfaces can be developed on an alluvial fan. Geomorphological processes and forms of the alluvial fan surfaces have great variations. For example, on the relict and old surfaces, channels and interfluves can be developed, wheeas on the young surface, bars and swales are dominant landforms. Dominant Processes on the relict and old fan surfaces are incision on the channel, wheathering and soil development on the interfluves, wheareas aggradation is the main process on the young surface of a fan. Differences in geomorphological forms and processes in the mentioned surfaces of alluvial fans can cause spatial changes in the soil characteristics and vegetation on the surface of alluvial fans. The purpose of this research is to investigate the impact of landforms and processes on the density and canopy of vegetation on the surface of an alluvial fan in the southeast of Shah Ghaib salt diapir in Larestan, Fars province. The mentioned alluvial fan consists of three surfaces including relict, old and young.

In order to calculate the vegetation density and canopy and their relations to the geomorphology, different surfaces of the stdy area alluvial fan including relict, old, and young surfaces, were identified. Aerial images were obtained by a DJI Phantom 4 Pro drone in nine paths in the apexes, mid-fans and toes of the fan surfaces. Based on the arial images prepared by drone, the density and canopy of vegetation cover were measured in 72 plots. Als, the 10 cm precision DEM (Digital Elevation Model) were obtained for 9 sections in the apex, mid-fan and toe of the three surfaces of study area fan. To compare the means of vegetation density and canopy variables in channels and interfluves, and also in bars and swales, the t-test were calculated. The One-way AVOVA test was used to evaluate whether the vegetation density and canopy variables in the relicl, old and young surfaces, as well as in the apex, mid-fan and toes of fan surfaces have a significant difference or not. The linear relationship between the vegetation density and canopy variables also was obtained.

Topographic cross sections of the fan surfaces prepared from the 10 cm precision DEM show that relict and old surfaces especially relict one are crenulated with higher channel incision (wide channels and short interfluves in the relict surface, and v-shaped channels and long interfluves in the old surface), whereas young surface is fairly smooth with bars and wsales landforms. Data show that the mean vegetation density is higher in the young surface (13.9%) compared to the relic and old surfaces, whereas the mean vegetation canopy in higher in the relict surface (10.44% ) than the old and young surfaces. Results reveal that the mean vegetation density is highr in the apexs (11.67%) than the mid-fan (10.22%) and toes (10.19%). Nevertheless, the mean vegetation canopy is lower in the apex (5.16%) than the mid-fan and toe (10.64% and 10.19% respectively) of the fan surfaces. In the relict and old surfaces, the mean vegetation density and canopy are higher in the channels compared to the interfluves. In the young fan surface, the means of both vegetation density and canopy are higher in the bars compared to the swals. Results of t-test show that there is a statistically significant difference between the means of vegetation density in the bars and swals, and also in the channels and interfluves. Also, there is statistically significant difference between the means of vegetation canopy in the bars and swals, and also in the channels and interfluves. Overal, vegetation cover is considerably higher in the channels of the relict and old surfaces of the fan, compared to the interfluves. This situation can be attributed to the higher shadow and moisture in the channels compared to the interfluves. Higher vegetation cover of the bars compared to the swales in the young fan surface can be associated with relatively better stability of bars than swales.

Alluvial fans can have different surfaces including young, old, and relic ones. These surfaces with different ages and also different morphology and processes can result in the variotaions in the vegetation type, density and canopy. In this study, the vegetation density and canopy of the relict, old and young surfaces of an alluvial fan located in the southeast of Shah Ghaib salt diapir were studied. Evaluation of the morphology of alluvial fan shows that the relict surface with deep channels and crenulated morphology is reltively older that the old surface, and the old surface with v-shaped channels is older than the young surface (with fairly smooth surface). Results of this study show that the vegetation cover is higher in channels than the interfluves in the old and relict surfaces of the fan, and also higher in the bars than the swales in the young surface of the fan. Overall, it can be concluded that the morphology and processes of the fan surfaces with different ages strongly control the vegetation density and canopy.

The phenomenon of land subsidence depends on many factors of geological phenomena, slow movements of the crust and the outflow of lava, human activities and draining of aquifers, land subsidence in agricultural lands in the plains causes the destruction of irrigation systems and the destruction of fertile soils. It will be accompanied by cracking and making the land unusable. The main problem of land subsidence is the irreversibility of the land. Persistent subsidence in the plains occurs as a result of indiscriminate extraction of groundwater and drainage of aquifers, which leads to compaction of clay layers. Iran is one of the countries that is facing the crisis of underground water resources in recent years, droughts, construction of dams, on the one hand, the increase in population, the need for water resources, excessive drilling of illegal wells, and the cultivation of aquatic species on the other hand. It caused the danger of water crisis in this country. The purpose of this research is to investigate the cultivation pattern and its role on the subsidence of Noorabad aquifer in Fars province.Currently, extensive cultivation of rice is carried out in this province and consumes water resources. From a long time ago, due to the rich surface water resources of the Bovan, Kati, Doregzan, and Marwarid rivers, as well as the suitable climate, farmers used to dedicate their lands to the cultivation of rice and safijat, and the passage of time and the reduction of surface resources Deep wells have continued the same flooding method as in the past and these species are still used as the dominant species in the region. The conditions have changed, but the cultivation is still in the old way, and this is one of the main problems that has doubled the subsidence crisis in the region as an important issue. Among the objectives of this research is to identify the types of water cultivation in the aquifer area, the areas with maximum subsidence and its relationship with the water types. One of the main innovations in this research is to investigate the relationship between the cultivation pattern and land subsidence for the first time. Is.Modifying the cultivation pattern is an important solution to prevent the progress of land subsidence by developing the cultivation of medicinal plants and transferring cultivation from open space to greenhouse space and developing planting and changing the time of cultivation from spring to autumn is a way to deal with water shortage. Actions such as pressurized irrigation and laser leveling and the implementation of protective vessels and the development of drought-tolerant gardens and the development of greenhouse cultivation along with training farmers to adapt to water shortages, modifying the cultivation pattern and preventing excessive extraction of underground resources are important measures. in reducing the effects of subsidence phenomenonThe method used in this research is analytical in order to prepare the cultivation pattern in the target area using Centil 2 images in the three months of the summer of 2021 in the GEE environment and it was prepared and then sampled using the support vector machine model in the ENVI software environment. (ROI) of the selected species was done in order to calculate the amount of subsidence using the radar interferometric method in the SNAP software environment.Investigating the amount of land subsidence in cultivated species shows that all cultivated species in the Noorabad aquifer are considered water-bearing and do not correspond to the conditions of the region. Rice cultivation is one of the most critical species in the Noorabad basin. Due to the high consumption of water and waterlogging and the high use of underground water resources, this species causes the drop of underground water and land subsidence. According to the graph, it shows that the amount of land subsidence in rice species has reached the maximum amount of about 10 centimeters per year. This situation is indicative of excessive wastage of underground water reserves and land subsidence in the Noorabad watershed. Sifijat is ranked second with a 3 cm settlement. These conditions indicate the crisis of subsidence in the region's aquifer.Land subsidence is a widespread phenomenon in the world, which has had significant quantitative and qualitative manifestations in the last few decades, mainly due to the excessive exploitation of underground water resources and the intensification of its level drop. The results of the study of land subsidence showed that several factors are effective in the occurrence of land subsidence. Therefore, the greatest impact on land subsidence is related to rice cultivation, which has the highest water demand in the summer season. Cultivation in a period of 1 year shows that rice has the highest rate with -10 cm of sediment per year, followed by safijat, with -3 cm. In these areas, due to meeting the water needs of residential communities, including the city of Noorabad and the surrounding areas, as well as meeting the water needs of agricultural activities, there is more water resource exploitation, and the extraction of underground water is very high. The factors with the intervention of the dry climate of this region have caused the high talent of these regions in the discussion of subsidence, and it has been identified as one of the critical areas of the city in the subsidence map. The results of radar interferometry show that the indiscriminate harvesting of underground reserves has caused the subsidence of the central part of the aquifer, including summer rice and corn, at the level of the danger zone of land subsidence, which has increased by 5 cm. The results obtained from the cultivation pattern and its relationship with land subsidence show a positive correlation of R2 coefficient equal to 98% and the lowest error rate is about 0.001

Khanmirza plain is one of the plains of cold and temperate regions of Iran, with an average rainfall of 500 mm per year and sufficient nutrition in terms of surface resources, the subsidence event is currently happening in it with a rapid trend. In terms of geostructure, Khanmirza plain is located in the folded Zagros zone in the south of the Dana fault, and the presence of piezometers protruding from the soil, as well as the presence of springs, etc., are signs of crustal movement on the surface of this plain. For this purpose, with the aim of evaluating the tectonic activity of the region in creating the phenomenon of subsidence from some geomorphic indices such as basin shape index (BS), river longitudinal gradient (SL), drainage basin asymmetry (AF), reverse topography symmetry index (T), integral index Hypsometry (H) of the region's subsidence was studied tectonically. Likewise, the subsidence rate was determined using radar interferometry. Examining these indicators showed that the indicators of basin shape (BS), river longitudinal gradient (SL), drainage basin asymmetry (AF), reverse topography symmetry index (T) are active tectonics in the region. Earth construction activities have caused the plain to stretch and become asymmetric on both sides of the main river. Likewise, the results of radar interferometry in the two-year period indicate that parallel to subsidence (at a rate of 9 cm) in some parts of the plain, other parts are facing uplift (at a rate of 21 cm).Collapse and subsidence can be caused by natural geological phenomena such as earthquakes, dissolution of limestone, chalk and salt rocks, melting of ice and compaction of deposits, slow movements of the crust and the release of lava from the solid crust of the earth, or activities human activities such as mining, extracting underground fluids such as underground water, oil or gas (Galloy and Barbie, 2011: 1459). Radar interferometry has been widely used by Earth researchers since the early 1990s (Shirani et al.: 2013). This technique can be used to measure displacements resulting from many phenomena such as earthquakes, landslides and subsidence. In general, there are nearly six hundred plains in Iran, and it is likely that more than half of them are subject to subsidence (Kia Sharifi, 2010: 58).

In order to evaluate the tectonic situation of the region, from topographic maps 1:50000 and geological map 1:100000 to calculate basin shape index (BS), river longitudinal gradient (SL), drainage basin asymmetry (AF), symmetry index Inverted topography (T), hypsometric integral index (H) from (DEM) 30 meters and topographic map were used, which were processed in GIS environment. D-InSAR radar images were used in the period from 2003 to 2005, which were processed in ENVI 5.3 software. Radar interferometry technique

How to calculate the SL river gradient index: The SL index is calculated for the middle point between two flow curves. Symmetry index of transverse topography (T): this index can also specify the state of symmetry and, as a result, the active or inactive state of the region. Drainage basin asymmetry index (AF): The asymmetry index is a method to evaluate the existence of tilts caused by tectonic activities at the scale of the drainage basin. Basin Shape Ratio Index (BS): Basins that have an elongated shape are tectonically active. And the shape of basins that are tectonically inactive tends to be round. Integral Hypsometric Index: Integral Hypsometric is an index that calculates the height of the entire area in relation to the area of the entire area. The values of this index show the transformation stages of the landscape in the erosion cycle. Today, radar interferometry, as a technique that estimates the displacement of the earth's surface with high accuracy and resolution, is a common tool for investigating the change of the earth's surface due to various factors, including land subsidence. In this technique, an interferogram can be prepared using two satellite images. So that by using the interferometric tool, the phases of the return signal from the ground are subtracted from each other in two time-delayed satellite images of the same region to extract changes in the ground surface. The radar interferometry technique uses Sarscape software as one of the powerful tools in the digitization of satellite images to survey the changes in the earth's surface. In this research, 12 Envisat satellite images from the European Space Agency were prepared

 The amount of subsidence calculated from 10 paired images is 9 cm drop in a two-year period, and the amount of elevation obtained from the images was calculated as 21 cm in a two-year period. By comparing these two numbers, it can be concluded that in this basin, the uplift rate is twice as high as the subsidence rate.The obtained values show that in addition to groundwater extraction as one of the main and common causes of subsidence, considering the tectonic factor in areas such as the Khanmirza watershed with high rainfall input is one of the main reasons for its formation.

The phenomenon of land subsidence can cause irreparable financial and human losses and damage many surface and subsurface structures in urban areas and their suburbs. According to the definition of the Geological Institute of the United States of America, the phenomenon of land subsidence includes the collapse or downward settlement of the earth's surface, which can have a small displacement vector, it is said to occur gradually and instantaneously on a large scale. The most important cause of the regional subsidence of the earth's surface in the sedimentary basins of arid and semi-arid regions is the condensation and compaction of sediments due to excessive extraction of groundwater sources. If watery clay layers are placed between sand layers, this phenomenon will be observed more widely and more acutely. Land subsidence usually occurs with a time delay after the long-term extraction of underground water resources. The amount of subsidence depends on the thickness and compressibility of layers, length of loading time, degree, and type of applied stress. With the decrease of the underground water level, the increase of the effective stress caused by the decrease of the pore water pressure causes subsidence. Usually, it takes time to reduce the water pressure and increase the effective tension; Therefore, following the reduction of the piezometric level, subsidence will occur with a time delay. Subsidence caused by the drop in fluid level mainly takes place in unconsolidated or semi-consolidated sediments that are located in the vicinity of sand layers. In such conditions, inelastic compaction occurs due to the increase of effective stress in the soil, the arrangement of the soil grains is disturbed and the thickness of the vertical layer decreases. In the areas where the sediments are not very thick and the underground water extraction continues indiscriminately, lines and cracks are observed on the surface of the land, especially agricultural land, and it is known as the Shaq phenomenon. The phenomenon of subsidence due to the withdrawal of underground water can have different intensities and destructive effects according to the geological situation and geotechnical characteristics of the region. In the sedimentary basins of arid and semi-arid regions, including the Mashhad Plain, the most important cause of ground subsidence is the density of underground water tables due to excessive water extraction. This situation is especially critical in the area where excessive pumping of aquifers containing sand layers is located between impermeable clay layers and causes subsidence. This phenomenon is also happening in Iran, and it is visible, especially in the eastern and central regions of the country, which suffer from drought and the water supply through underground water extraction has greatly increased. Mashhad Plain is one of the areas with a very high subsidence rate, which needs to be given more attention. Land subsidence is a dangerous global problem, and geometric methods are not suitable for extensive and serious monitoring of land deformation.

Radar interferometry with artificial valve is a remote sensing technique. In which two or more radar images are used to produce digital elevation models or to map the displacement of the earth's surface. In the above article, using radar data and using radar interferometry technique and small baseline time series analysis, the time series of land subsidence phenomenon in Mashhad is monitored and measured.In the present study, using radar interferometry and SBAS time series method, in the period from 2014 to 2021 in Mashhad city, by selecting 38 Sentinel-1 images with a suitable time interval, the average speed of land subsidence and uplift in the studied area was estimated.Then, to determine the main factors of this event, the studied area was investigated in terms of changes in the underground water level and tectonics.

The results of the analysis of the time series of the images showed that in Mashhad, the maximum ground displacement is between -77 and +8 mm, and the areas with subsidence are located in the northern parts of Mashhad, which is recorded between 30 and 30 mm. 77 mm subsidence per year. To determine the cause of this event, tectonic assessment and the status of underground water exploitation in this period and its relationship with land subsidence and earthquake data in the area were investigated.

The results of the research showed that the maximum subsidence rate is 77 mm in the area of Mashhad in the period of 7 years from 2014 to 2021 and is related to the north of Mashhad. It should be noted that while advancing towards the city center from the north, you should look for irreparable damage shortly. To check the accuracy of interferometry and interpret the results and investigate the possible cause of the subsidence of Mashhad city, the trend of changes in the water level in piezometric wells, this factor in the occurrence of subsidence in the region was investigated. The information on piezometric wells was obtained in the city of Mashhad, the results of which strongly showed the water level in the past years, which is based on the cause of subsidence in this area. Only in the center is the temporary rise of the underground water level due to the feeding of the urban Mashhad aquifer.Then, to investigate the tectonic participation in the subsidence event, the history of earthquakes and the fault network of the region were evaluated, which confirmed the absence of the investigated earthquakes (maximum 3.8 on the Richter scale) in the region and its surroundings, and there is no fault network within the area of the subsidence assets. did not have. There is no activity. The probability of supposition and the possibility of technology playing a role in the subsidence event is insignificant. Small cracks are mainly created near mental wells or agricultural water exploitation wells and are scattered much more.

The risk of subsidence can be an important factor in increasing the vulnerability of the center of human activities located in areas with natural hazardous infrastructure such as earthquakes. In recent years, this phenomenon has caused a lot of damage to the plains and cities of Iran, especially to residential buildings, plains and agricultural lands located in Chaharmahal and Bakhtiari provinces. Therefore, monitoring the amount of subsidence and dealing with its influential causes in order to control and manage its vulnerability is of particular importance. So far, various methods have been used such as using GPS, precision instrument alignment and radar interferometric method to measure land subsidence. In the meantime, the radar interferometric method is an up-to-date and effective technique for measuring changes in the earth's surface worldwide. In this article, satellite data and radar interferometric technique have been used to measure the subsidence risk of Lordegan plain and urban settlements. For this purpose, the amount of subsidence in a period of 6 years (from 2017 to 2023) has been evaluated using Sentinel A1 data using SNAP software. The results of field observations indicate that the occurrence of subsidence and proportionally the drop of groundwater level is due to excessive extraction of underground water. The data obtained from the piezometric wells of Lordegan city and Barm spring indicate a sharp drop in the underground water level since 2008. The amount of groundwater dropping has been observed in some areas up to 15 meters. The results obtained from the radar data showed that during a 6-year period, Lordegan city has experienced an amount of subsidence of about 14 to 18 cm. These subsidence amounts are about 3 cm per year, which is at the warning level and beyond the normal state. So, accurate management of the withdrawal of underground water seems essential by considering the significant rate of subsidence and its risk.

Radar images obtained from virtual aperture radars (SAR) with the ability to measure the length of the vector from the sensor to the ground surface, are widely used in measurements related to the preparation of digital elevation maps. The technique used in this method is known as radar interferometric technique (InSAR). In radar interferometry, the phase obtained from two images taken from a certain area is interfered to produce an interferometer. In fact, the interferogram is the different product of two radar images. In the interferometry method, the mixed radar images that have the return phase values from the complex to the sensor are combined with each other and an image called the interferometer is produced. Hence, interference is obtained from the phase difference of two images taken at two different times, which are geometrically precisely matched. By using the phase difference information available in the interferometer, which indicates the distance difference between the sensor and the object, it is possible to prepare the deformation variable of the earth's surface or earth's topography. In this research, C-band radar images of the European Space Agency's Sentinel-1A satellite were used in the period of 02/05/2017 to 01/29/2023 at the level of a SLC and in IW mode with high resolution with VV polarization. In addition, in the data processing stage, sub-band IW1 and segment 2 to 3 images were used.

The radar interferometry method measures changes in the earth's surface along the line of sight of the satellite. Due to the fact that the major changes in the land surface in subsidence are in the form of height changes, the displacements extracted by the radar interferometric method can be converted into height changes by ignoring the horizontal changes in the ground surface and depicting them in the vertical direction. Each interferogram individually only contains surface changes in one time interval. By using a number of interferograms along with time series analysis, surface changes can be examined over time. Analysis of time series using radar interferometric method is a suitable method for estimating the rate of land surface changes in high spatial resolution. By having two images with different time intervals from satellite images, the rate of subsidence and vulnerability of an area can be calculated at any point and date with the radar interferometric method. It is worth mentioning that the radar interferometry technique is one of the most up-to-date and accurate tools for calculating the rate of land surface changes in the world and is being used all over the world.

In this article, using the radar interferometric technique, the state of the subsidence phenomenon in Lordegan city and the damages caused around the Barm spring in Lordegan city have been discussed. In summary, the most important results obtained are:• The results obtained from the rainfall data and different hydrographs of the plain showed that, the amount of rainfall and the level of underground water have significantly decreased since 1986, for example, the level of underground water has decreased from a depth of about 15 meters from the ground surface to a depth of about 33 meters. The results of the radar interferometry technique to depict the range of subsidence, showed that the total maximum amount of subsidence between the years 2017 and 2023 was about 18 centimeters, which is about 3 centimeters of annual subsidence. based on the evidence and investigations carried out on the Barm spring in Lordegan city, it was determined that the volume of water spring has significantly decreased. It should be noted that the construction of heavy structures and other constructions near the spring has also affected the water flow and the reduction of the flow of this spring. In recent years, numerous damages have appeared in the city and around the Barm spring, for example, the appearance of numerous and annual cracks on the streets and the path of the old aqueducts, cracks and damage to the stone walls around the spring, damage to buildings.