فصلنامه پژوهش های ژئومورفولوژی کمی
سال دوازدهم شماره 3 (پیاپی 47، زمستان 1402)

How the first human settlements came to be is an important issue, and from different scientific perspectives, different answers can be given; because the creation or degeneration of these settlements is not the choice of individuals; it depends on countless human and natural conditions. Studies show that the establishment of human societies on the ground has always been done in order to achieve maximum natural resources such as water resources, adequate vegetation and access to arable land, this effort is undoubtedly based on the principles that today It is interpreted as the science of location. At the beginning of human life, natural hazards were unknown to humans until their occurrence. Natural are also safe. Natural disasters are born of natural elements and factors, but human profiteering intervention in nature affects the quantity and quality of many natural disasters. Considering the mentioned cases, environmental factors, especially geomorphology, have played an important role in locating residential areas throughout history. Accordingly, in this study, environmental factors affecting the distribution of ancient settlements in Piranshahr have been investigated.

In this research, in order to achieve the desired goals, a 30-meter-high digital model, a layer of ancient sites identified in the region (Masoumian, 2021), a 1: 100000 geological map and a 1: 50,000 topographic map of the region have been used. The most important tool used in the research was ArcGIS and also in this research the combined model of fuzzy logic and AHP has been used. This research has generally been done in two stages. In the first stage, after preparing the layer of ancient sites in the region, the location of ancient sites in terms of slope, slope classes, elevation classes, distance classes from the river, lithology units and geomorphological units are analyzed and thus the distribution status of sites Ancient has been analyzed in relation to environmental conditions. In the second stage, in order to identify areas prone to ancient settlements, the results of the previous stage have been used and using the integrated model of AHP fuzzy areas, a map of areas prone to ancient settlements has been prepared.

In this study, in order to investigate the effects of environmental conditions on the distribution of ancient settlements, first the location of 67 ancient sites in Piranshahr city has been determined. According to the results, a large part of the ancient settlements are located in the slope classes less than 10%, so that 32 ancient sites (equivalent to 47.8% of the identified sites) are located in this class. In terms of slope, a large part of the ancient settlements are located in the northern directions so that 36 ancient sites (38.8% of the identified sites) are located in the northwest to northeast. In terms of height, a large part of the ancient sites are located in the altitude classes of 1250 to 1650, so that in this category there are 56 ancient sites (equivalent to 83.6% of the identified sites). In terms of distance from the river, a large part of the ancient sites are located near the river, with 48 ancient sites (equivalent to 71.6% of the identified sites), located less than 500 meters from the river. They had. Lithologically, a large part of the settlements are located on Quaternary alluvial sediments, so that 37 ancient sites (equivalent to 55.2% of the identified sites) are located in this unit. Also, in terms of geomorphology, a large part of the ancient sites are located in the alluvial plain unit, so that 37 ancient sites (equivalent to 55.2% of the identified sites) are located in this unit.

Environmental conditions have played an important role in the settlement of residential areas in the past and today. Considering that the knowledge of the effective factors in location selection has an important role in various planning, in this study, the effective environmental factors in the establishment of ancient sites in Piranshahr city have been analyzed. Based on the results, the distribution of ancient sites was directly related to environmental conditions, so that the highest density of ancient sites in low-slope areas, low-lying areas, areas near the river, north slope directions, unit Quaternary alluvium as well as unit of alluvial plains. According to the results obtained at this stage, areas prone to the establishment of ancient settlements in Piranshahr city have been identified that based on the results, the middle areas of Piranshahr city due to the conditions, are prone to the development of ancient settlements. The results of this study have shown that environmental conditions in the past have played a major role in the distribution of residential areas and by examining the environmental conditions of each area to a large extent can be found the existence of ancient sites in that area.

In recent years, flood phenomenon has been one of the hydroclimatic events and one of the most serious natural hazards that has threatened human societies. Indiscriminate exploitation of forests and pastures and land use change and their transformation into unsuitable agricultural lands, along with the indiscriminate construction of residential areas, have caused an increase in floods. Therefore, the flood phenomenon is very important. Therefore, the present study was conducted with the aim of analyzing the spatial correlation of changes in vegetation cover with the height of runoff in the Gorgan River watershed in a 21-year period. For this purpose, from the data of slope, soil type, land unit and land use to prepare the hydrological response unit and Landsat images of different years (2000-2021) to investigate changes in vegetation density using the NDVI index in each of Hydrological response units are used. In this regard, 72 hydrological response units were prepared as basic units in the study area. Also, the height of the runoff was calculated by the SCS method in each of the hydrological response units using the criteria of rainfall height, soil hydrological group, vegetation, land use type and soil texture, so that the cities of Agh Qola, Simin Shahr and Gomish Tepe and the Gorganrood River in the height of the runoff There are many. The results of the analysis of 78% of the spatial correlation between the height of runoff and the density of vegetation showed that the agricultural and garden lands in the plains have increased significantly, while the density of forest and pastures has decreased in the 21-year period. This factor is caused by human activities such as the destruction of forests and pastures and the cultivation of these lands and the development of cities, the height of the runoff has increased. While in the highlands, due to more infiltration, despite the decrease in vegetation density, the runoff height is also low.

Groundwater depletion is one of the scenarios of climate change, which has become a global crisis today. Land use changes and land cover and rapid urbanization are the main causes. The decline of groundwater in recent years has caused land subsidence in many alluvial plains of the country. Uncontrolled and uncontrolled consumption of surface and groundwater resources, reduction of precipitation, concentration of consumption in some places (Imbalance between demand and water supply potential), inadequate cultivation pattern and lack of proper irrigation and digging of multiple wells and operation Irregularity of them in recent decades has caused a critical situation of groundwater resources in most plains of the country. To Groundwater level in most of the country's aquifers is constantly declining and the average annual decline over It has been 12 meters for the last 15 years. Decreasing the groundwater level of the plains increases the cost of water extraction and Increased energy consumption, reduced water quality and the emergence of land subsidence. As side effects, with decreasing volume The phenomenon of subsidence occurs in different spatial and temporal situations with different characteristics such as groundwater content, morphology, pedology and geology, which have different destructive effects. Shabestar-Sufian plain is one of the plains in the northwest of the country, which is facing many restrictions in terms of access to surface water and groundwater and is in a critical situation. In recent decades, the increasing trend of irrigated agricultural lands and overexploitation of groundwater resources has put the plain at risk of subsidence. Groundwater level drop is one of the most common causes of subsidence. Recognizing and examining ways to control it and prevent accelerating the process and expansion of subsidence phenomenon prevents the occurrence of hazards such as groundwater pollution, land slope change, well wall collapse, gradual sinking of masts and structures, changing the slope of rivers and roads Be. Risks that cause significant financial and human losses and on the other hand cause a waste of time and manpower, and pollution and destruction of the environment. In Shabestar-Sufian plain, there may be signs of subsidence in the form of sloping pipes, piping, shallow cavities, which is a warning for this fertile plain. If proper planning is not done regarding the exploitation of groundwater, we will soon see the destruction of lands, houses, water pollution, etc. In this regard,. The aim of this study was to identify areas prone to subsidence, for which the Fuzzy-AHP model was used. Information layers including land slope, altitude, geomorphological units, distance from the river, land use, lithology, groundwater level decline have been used as effective criteria. Expert Choice software was used to perform the calculations and after obtaining the final weights of each criterion, the obtained weight was applied on the layers according to the expert opinions in GIS software. Also, for the fuzzy model, fuzzy maps were combined using the fuzzy gamma operator. To modulate the very high sensitivity of the multiplication fuzzy operator and also the very low sensitivity of the sum fuzzy, the gamma fuzzy operator has been used and finally a map of subsidence prone areas has been prepared. Landslide risk areas are classified into five categories: very low (10.8%), low (14.2%), medium (7.22%), high (7.28%) and very high (2.23%). have became. About 52% of the southern, middle and western regions of the region are at very high risk of landslides due to excessive use of groundwater. In terms of spatial distribution, the highest risk of land subsidence is in the villages of Aq Kahriz, Dizaj Khalil, Shanglabad, Bagherabad, Kafi Malek, Kushk, Hallaji, Yousefabad, Ali Biglou, Haftcheshmeh and Qom Tappeh. Complete and common data were used between 2001 and 2017. Water loss map was prepared by idw interpolation method in gis environment. The results of groundwater status assessments in the region indicate that the study area in recent years has been faced with an increasing trend of groundwater level decline, so that the rate of water level decline has reached 4.7 meters in 18 years, a sharp drop in land subsidence in this region Has caused. . The calculated results are confirmed by examining the time series of water level drop in the wells of the region. Analysis of geomorphological parameters of the region has also shown that the same occurrence of subsidence has been in areas with a slope between zero to 5 valleys, have experienced less subsidence in the slope of more than 5 degrees or no subsidence has occurred in these slopes at all. It has a high subsidence in places with a height of less than 1500 meters, and with salt cover and alluvial materials, as well as areas with agricultural use. Areas close to the river were less prone to subsidence. Flat and smooth slope directions have been the main area of occurrence of this phenomenon. It can be concluded from the results that more than half of the 5% (51%) of the study are prone to high to very high subsidence, this means the critical situation in this plain.

The increase in human activities in recent decades, the increase in population, the development of agriculture and industries has caused a sharp increase in water consumption and, as a result, the quantitative and qualitative reduction of underground water resources and created a vulnerable environment, and exposed underground water as a natural resource to industrial and agricultural pollutants. At present, a significant part of the country's water consumption is provided by underground water sources, which are mainly open aquifers and have higher vulnerability. Assessing the vulnerability and pollution of the aquifer is necessary for the management, development and allocation of land use, how to monitor the quality, prevention and protection of groundwater pollution. During the vulnerability assessment process, attention is paid to transfer and flow models in saturated and unsaturated areas, and the effect of physical processes of water movement and the path related to pollution transfer, feeding and penetration depth in pollution transfer are simulated and the distribution of sensitive or vulnerable areas is evaluated.
The area studied in this research, Mashhad plain aquifer, is quantitatively in a critical prohibited situation, and qualitatively, it has faced serious challenges. Therefore, the general purpose of this research is to identify and analyze the qualitative vulnerability of the Mashhad plain aquifer, which causes the potential of vulnerability to pollution to be determined more accurately.

An open aquifer is spread throughout the Mashhad plain, which is not the same in terms of discharge. The Mashhad plain aquifer with an area of 2700 square kilometers is located in the geographical coordinates of 58°29' to 59°56' east longitude and 35°58' to 37°03' north latitude in the catchment area of the Kashafroud river. The main drain of this region is the Kashafroud river, which flows from the northwest to the southeast in the Mashhad plain. Various formations from the first to the Quaternary period can be seen in this area.
In this research, the vulnerability assessment of the aquifer was done with SINTACS and GODS models, and the ArcGIS environment was used to analyze the parameters and prepare the vulnerability map.
The SINTACS model includes seven hydrogeological parameters, which are: (S) groundwater depth, (I) net nutrition, (N) effect of unsaturated zone, (T) soil type, (A) aquifer environment, (C) hydraulic conductivity, (SV) topography (slope), (w) weight and (r) related rank to each of the parameters. A relative weight is assigned to each of the parameters, which indicates the relative impact of each characteristic on the transfer of pollution in groundwater. In this method, the vulnerability index is obtained according to equation 1:equation (1): SINTACS Index=S_Or S_Ow+I_r I_w+N_r N_w+T_r T_w+A_r A_w+C_r C_w+S_Vr S_Vw ∑_i^7▒〖I_SINTACS=P_i×W_i 〗

In the GODS method, four parameters of: (G) aquifer type, (O) Characteristics of unsaturated zone, (D) depth of underground water and (S) type of surface soil texture are used. The GODS vulnerability index is obtained from the product of the parameters and based on equation 2:equation (2): I_v=G×O×D×S

To prepare the vulnerability map of the aquifer, the layers of each model were combined in the ArcGIS and the final map was obtained. Then the area of each floor was calculated. According to the SINTACS model, the Mashhad plain aquifer is divided into five zones with very low vulnerability (0.44%), low (25.57%), moderate (28.58%), high (2.79%), very high (42.61%). Also, based on the results of the GODS model, the study area is divided into five zones with very low vulnerability (0.93%), low (31.11%), moderate (11.45%), high (1.56%) and very high (54.95%).
The validation results of the vulnerability maps showed that both SINTACS and GODS models are highly accurate in zoning the vulnerability of the Mashhad plain aquifer, so that the correlation coefficient of the vulnerability maps with the qualitative index of TDS is (0.91) in the SINTACS model and (0.85) in the GODS model.

In both models, the largest area of the Mashhad plain aquifer in terms of vulnerability is located in the zone with very high risk, while the smallest area is located in the zone of very low vulnerability and then in the zone of medium vulnerability. In general, the vulnerability of the Mashhad plsin aquifer increases from the southeast to the northwest, and then the vulnerability decreases from the central areas of the range to the extreme northwest.
The reason for this can be attributed to the direction of the underground water flow, which is from east to west, as well as the high water table in these areas. Also, clearly, areas with medium, high and very high vulnerability are compatible with the uses of water agriculture, gardens, population and industrial centers. In terms of the type of sediments in the aquifer environment, sandy and sandy ranges show moderate to high vulnerability due to higher permeability, While there is the lowest level of vulnerability in clay and silty areas. The results of the current research can be used in environmental assessments and analysis of various pollutions and can be used as a basis for management decisions.

The space syntax and its models is a method of visualizing the spatial relationships of places and analyzing the environmental configurations of settlements, in which novel titles such as territorial land-contexts, land-texts and configuration are examined as components of spatial analysis in the arrangement of settlements and the environmental relations of settlements.
Coastal land-contexts are among the geographical land-contexts that are the legacy of sea level changes and where a large population of people of the world have settled. What becomes important in this research is the understanding of the geographical analysis of the rules of the layout of the coastal land-context, which has created a unique identity and differences in the landscape and diverse social and environmental configurations. The fundamental question here is that the southern coast of the country with the unique nature of the mangrove marine ecosystem can be introduced as a marine garden city, in a way that, inspired by the rich Iranian-Islamic culture, meets the needs of a new sea-based civilization.

The current research is compiled according to the phenomenology method;
In the first step, it was determined and recognized the space of the research field. Then, by field investigation and study of library sources and articles, the database was collected.
In the next step, the frequency distribution of the research hydrogeomorphic arrays (height, slope, slope direction) is first analyzed as two spatial dimensions, and then the two parameters of distance from the coast and distance from waterways in relation to the number of foci Demographics and their population are analyzed in the scope of the research.
In the next step, relying on the phenomenological method, it has been analyzed (urban and rural settlements) and after identifying and analyzing the existing social configurations and their identity context, it has been introduced to Marine Garden City Metropolis and the role of configurations We examine the existing social issues in creating a new and smart configuration of Marine Garden City Metropolis.

Hydrogeomorphic Arrays
Height as the first hydrogeomorphic component is examined in order to limit the development of settlements. The results show that with the increase in altitude above sea level, the number of urban and rural settlements and their population decreases.
The second hydrogeomorphic component is the slope. The results show the number of urban and rural settlements and their population in the 0-2 percent slope class has increased and the difference between this class and other classes has increased.
The third hydrogeomorphic component is the direction of the slope. The results show that most of the urban and rural settlements are located in the direction of the slope from east to west.
Distance from the beach
The results show that most of the urban and rural settlements are located at a distance of 5 kilometers from the coast, and with the distance from the coast, a decreasing trend in their number and population is observed; As a result, the beach is considered the best factor in attracting the population of urban and rural settlements.
Distance from waterways
The results show that the largest number and population of urban and rural settlements have been formed at a distance of 500 meters from waterways, and as this distance increases, the number and population of urban and rural settlements decreases.
Explanation of mangrove land-context and social configurations
The mangrove land-context has a unique identity that has created various landscape differences and environmental configurations. In order to explain and extract the logic of the land-texts syntax in the mangrove land-context, the transformational role of the distance of the settlements from the waterways and the distance from the coast in this area is addressed, and the population centers of the mangrove land-context are explained as the land-texts of the research scope. Each environmental social configuration in the mangrove land-context have an independent and unique identity, which are described in the form of urban configuration, rural configuration, nomadic configuration, coastal configuration, and mangrove configuration.

In this research, while proposing new concepts in the knowledge of geography with the phenomenological method, some fundamental issues of social configurations existing in the coastal mangrove land-context were explained and analyzed. In the first step, "mangrove land-context" was introduced and analyzed. Also, in order to identify and obtain the environmental components and to examine the layout of the population centers of marine garden city, some of the environmental components effective in the establishment of these coastal civil centers were selected and analyzed.
Distance was considered as the most important basis of place identity in the spatial analysis of marine garden city, because this index has served as the most attractive component in the history of settlements on the northern shores of the Persian Gulf. Also, by examining and analyzing the syntax of population centers in the scope of the research, urban, rural, fishing, mangrove and nomadic configurations were identified.
Considering the above and regional competition and its continuation in the Persian Gulf, the development of coastal areas should not be focused on population displacement, but the creation of coastal settlements in the form of marine civil production centers is a good solution against the formation of sea-based and air-based development in the southern coasts of the Persian Gulf. Therefore, it can be concluded that the interaction of the coast and the sea is the main factor in the formation or revival of a maritime civilization or a pattern of sea-based civilization based on a unique natural environment, i.e. mangrove habitats, which can be considered as a complementary necessity. Continental civilization is part of Iran's long-term development and progress goals, which is the fundamental infrastructure for the crystallization of maritime civilization and guarantees Iran's dynamism in international scenes.

Due to Iran's location in the Alpine-Himalayan orogeny , Iran is one of the most active areas in terms of infrastructure, of which the Sanandaj-Sirjan is a part. Sanandaj-Sirjan zone is the busiest structural zone in Iran, which has been formed as a part of Zagros orogeny and Alp-Himalayan orogeny system due to the convergence of the northern part of Gondwana and southern Eurasia at the end of the Mesozoic. Studying and recognizing active tectonics is very important in risk assessment, especially in areas with relatively high tectonic activity in the Holocene and Pleistocene, given that most active tectonic processes can damage human structures and be associated with sudden events. , Recognizing active tectonics in an area can reduce the risks of these events. Morphotectonics represents the relationship between tectonics and surface effects, and morphotectonic indicators are basic tools for rapid measurement and detection of areas with tectonic deformation.
Geomorphology represents the relationship between tectonics and surface features, and geomorphology indicators are preliminary and basic tools for rapid measurement and diagnosis of areas with tectonic deformation.

In this research, the active tectonics of a part of Sanandaj-Sirjan zone in the north of Kermanshah has been investigated, for this purpose, the indicators of the longitudinal gradient of the river (SL), hierarchical anomaly (Hi), branches (R), the shape of the drainage basin (Bs) and sinusitis mountain front (Smf) was measured in 54 watersheds in the region by By geographic information system (GIS(. Finally, the results of quantitative calculations were compared and analyzed with field observations in the region.

The values of five morphometric indices, including river longitudinal gradient (SL), hierarchical anomaly (Hi), branches (R), drainage basin shape (Bs) and sinusitis mountain front (Smf), were calculated separately for 54 basins in the study area. and finally a zoning map of the level of tectonic activity was prepared by combining the values obtained from the morphometric indices, the longitudinal gradient index (SL) of the river has high values in the eastern and southern parts of the studied area. In the east of the studied area, the northern basins of the Sahne fault and the southern basin of the Mianrehan fault show high and very high values of this activity index, which indicates the effect of the activity of the Sahne fault in this part of the region on the river slope. In the south of the studied area in the area of Biston-Taqbestan fault zone, basins 37, 43, 44, 48 have relatively high values of river longitudinal gradient index (SL).
Hierarchical anomaly index (Hi) and branching index (R) have high values in the western and eastern basins of the study area. Basins 22 and 25 in the north of the Sahne fault and the basins including the Morvarid fault have high activity based on these indicators. Also, the basins in the south of the region in the range of Koh-Safid fault and Qarasu fault, Biston-Taqbestan fault zone, as well as the southern basins of Qeshlaq fault in the west of the studied area show high values of these indicators. The drainage basin shape index (Bs) has the highest values in basins 49 and 47 in the south of the study area in the range of Koh Safid and Qaresu faults, basin 26 in the north of the Sahne fault, basin 12 in the north of the Marwarid fault and basin 37 in the north of the Biston fault zone. It has a vault. The elevations formed due to the activity of Sahne, Mianrahan, Morvarid and Biston-Taqbestan fault zone with a straight mountain front have the highest values of mountain front meandering index (Smf). Based on the results of calculating the mentioned indicators and preparing a map of tectonic activity by combining the values of these indicators, in general, the southern and eastern half of the study area have higher relative tectonic activity than the western and northern half. Biston-Taqbestan fault zone in the southern half of the study area and Sahne-Marwarid fault zone in the east of the study area have the most tectonic activity. All the basins north of the Sahne fault have high relative tectonic activity based on the indicators of longitudinal gradient (SL) and branches (R). Also, basins 17 and 26 have high values of basin shape index (Bs) and basins 22 and 26 have high values of index (Hi).

According to the studies, the current tectonic activity is very high in the Sahne-Morvarid fault zone as part of the main Zagros fault (MRF) and the Biston-Taqbestan thrust zone, and the moderate and relatively high activity in the Mianrahan fault and the Koh Safid fault zone. The title of a branch of the Zagros Thrust Fault (ZTF) in the study area can be inferred based on the results of the morphometric indices, as well as the high compliance of the earthquakes with the relative tectonic activity level zoning map based on the morphometric indices (Iat) in the study area. The importance of using (Iat) as primary studies to identify seismic areas and long-term earthquake prediction in areas with high tectonic activity.

One of the main issues in drainage watersheds is erosion and sediment yield. Lack of proper management in this field can be environmental hazards and even a threat to human life. The purpose of this study is fingerprinting the sources of sediment yield in sub-basins 1 and 2 of Talar drainage basin in Mazandaran province.140 soil samples in first approach and 80 samples in second approach collected respectively sub-basin 1 (77) and (47), sub-basin 2 (63) and (33) of lithological units and range of peak ground acceleration and 20 drape sediment samples at the outlet sub-basins and 28 geochemical elements measured as tracers in the samples. Using the Kruskal-Wallis test and discriminant function analysis, the composite fingerprints was determined. The largest relative contribution of sediment yield based on the Bayesian un-mixing model is in the first approach (sub-basin 1 unit sandstone and conglomerate with 59.1%, sub-basin 2 unit marl and shale with 47.2%), in the second approach (sub-basin 1 unit the range of peak ground acceleration at the level (0.51-0.6) g with 50.3%, and sub basin 2 units channel bank with 64.6%). The results of this study showed that the range of peak ground acceleration have a direct effect on control of sediment yield and erosion processes. Also, division of lithological groups as sources sediment yield based on range of peak ground acceleration, which have a great impact on sediment yield, as a new approach, can be of great help in understanding sediment yield processes.

Land subsidence is a geological hazard that occurs in connection with human activities and environmental changes. This hazard has occurred in 60 countries and more than 150 cities of the world. Similar to many regions of Iran, the southern plains of the Alborz mountain range are facing rapid land subsidence in connection with excessive extraction of groundwater. Considering the average water consumption and the scattered data related to the drop in the underground water level in the country, it is not difficult to recognize that subsidence and its consequences have become a problematic phenomenon in the country. In recent years, many cracks have appeared in agricultural lands and residential buildings, streets and infrastructures of the study area; In such a way that in the agricultural sector of the region, it has caused the destruction and destruction of part of the lands, and in the residential sector, it has caused successive settlements in the buildings and caused irreparable damages.

In this research, data analysis was done in several stages, which are described below. In the first stage, using the information related to the water level drop of the wells in the studied basin, the amount of changes in the water level of the wells was calculated and then a map of the groundwater level drop in the studied basin was prepared. In the second step, using Sentinel 1 images for a period of 5 years (January 2017 to January 2022) and using the SBAS time series method, the amount of subsidence of the studied basin has been calculated. At this stage, the desired images with 24-day intervals have been prepared. After preparing the images, Linux operating system and SNAP software have been used to process the images. In the next step, the correlation between the amount of subsidence with the state of groundwater level drop in the region and other geomorphological parameters has been evaluated, for this purpose, the interpolation map related to the drop in the groundwater level of the region was entered into SPSS software in pixel format and then the subsidence map was also created. In the same way, it was entered into the SPSS software, and in this way, the relationship between the amount of subsidence and the groundwater loss of each pixel was evaluated together. At this stage, using the integrated model of fuzzy logic and AHP, areas prone to subsidence have been identified. To do this, first, the desired parameters including lithology, height, slope, the amount of groundwater loss, proximity to the river and topographic units have been selected. After preparing the desired information layers, the layers are scaled based on the subsidence potential. After fuzzy membership of the layers, the layers are weighted based on the opinions of experts (3 Geomorphologists) and the Analytical Hierarchy Model (AHP) and finally, the layers of information are combined using the fuzzy gamma operator and the final map of the areas prone to subsidence is prepared.

The area of Hashtgerd Plain lacks the variety of geomorphological landforms and is mainly located on the plain and old conifers. The absence of geomorphological barriers has made the residential and agricultural development in this area not to face much restrictions. Therefore, in the period of 30 years, there have been major changes in the land use of the region. The land use map of the studied area during the years 1990 to 2020 shows the increase of residential and agricultural uses. According to the results of calculating the water level drop in the studied wells, in this research, using the spline interpolation method, an annual groundwater drop map has been prepared in the study area, based on this, the middle and southern areas of the range Studies have the highest average annual groundwater level drop.
The correlation between the annual average drop of the underground water level and the amount of subsidence has been evaluated, and the results show that the correlation coefficient between them is about 7%. According to the results, it can be concluded that the Hashtgerd range has experienced subsidence between 18 and 320 mm in our five-year period.

Land subsidence will ultimately be the "death of the aquifer" and the destruction of agriculture and horticulture in the Hashtgerd Plain. With the continuation of this process, the fertile lands of Hashtgerd region will face a dark prospect and irreparable social and economic effects will affect the region. The results of radar interferometry indicate that the amount of subsidence in the study area during a 5-year period is between 18 and 32 cm. The final subsidence map shows that the highest amount of subsidence is in the southern and western areas and the lowest amount is related to the northern areas of the study area. Based on the assessment of areas prone to subsidence risk, it can be seen that the results of radar interferometry are highly reliable to a significant extent.

Debris flow, which is known as the most destructive natural hazard, is a complex environmental phenomenon in which a large volume of moving mass including mud, sand, rock, soil, water, and air travels down a slope under the impact of gravitational force. Due to this phenomenon's complex physical nature, the governing equations' analytical solution is complicated and almost impossible in real situations.
In the last two decades, with the advancement in computer technologies and numerical methods, some robust software has been developed to simulate debris flow and particle movement. The Rapid Mass Movement Simulation (RAMMS) is a two-dimensional model to calculate the motion of geophysical mass movements (snow avalanches, rockslides, debris flows, and shallow landslides) from onset to runout in three-dimensional terrain. Since the numerical analysis in this software is based on the terrain parameters which are extracted from a Digital Elevation Model (DEM), the accuracy of the model might be very dependent on the resolution of the DEM. For this reason, this study's main aim is quantitively evaluating errors and uncertainties in RAMMS-Debris flow model outputs induced by the impact of DEM cell size.

RAMMS extracts all topographical parameters (i.e., slope angle, flow directions, streams, altitudes, inundation areas) from a DEM (ASCII or GeoTIFF format). Since the resolution of the DEM and the resampling process can significantly affect the physical terrain parameters of a given watershed such as the mean slope, altitudes, the cross-section of rivers, etc., therefore the RAMMS outputs may be altered with the changing of the DEM resolution which causes the propagation of errors in modeling and calculations.
To investigate the impact of DEM cell size on the accuracy of RAMMS-Debris flow modeling, a watershed with high-resolution DEM (1 m), located in northeastern Iran, is considered. Then, this basic DEM is resampled using the bilinear method in ArcGIS to build DEM maps in various cell sizes such as 2, 3, 4, 5, 10, 15, and 20 m. Since the modeling process is based on the Voellmy-fluid friction model, the viscous-turbulent and the Dry-Coulomb type friction coefficients are considered constant at 200 and 0.2 respectively. Also, all other input data such as simulation time, inflow hydrograph, fluid density, etc. are considered constant for all scenarios.

The analysis showed that by increasing the DEM cell size from 1 meter to 20 meters, the mean slope of the computational domain decreased up to 4% such that, changing in DEM cell size from 1 meter to 10 meters decreases the mean slope by only 1% but with increasing the cell size to more than 10 m, the mean slope reduces significantly.
In addition, the final results showed that the RAMMS model had an extreme sensitivity to the Dem cell size such that by keeping other parameters constant, only changing the Dem cell size from 1 meter to 20 meters caused an error of +548% in the overall inundation area, -67% in the overall maximum flow depth, and +112% in the run-out distance. It was also found that the magnitude of errors in the modeled debris flow parameters using DEMs with a cell size of less than 5 meters was almost small whereas for cell sizes larger than 5 meters, it was very large. Therefore, it seems that the RAMMS software generally works well only for DEMs with tiny cell sizes (less than 5 meters).

In this research, the effect of the cell size of the Digital Elevation Model (DEM) on the accuracy of the results of the RAMMS model has been investigated. For this purpose, a DEM with a cell size of 1 meter was selected in an area that is prone to debris flow, then using ArcGIS software, some coarser maps with cell sizes of 2, 3, 4, 5, 10, 15, and 20 meters were made using the bilinear method. based on the results obtained from the modeling of various scenarios in this study, it is found that the RAMMS model has an extreme sensitivity to the cell size of the DEM map. Although the smaller the cell size of the DEM map, the higher the accuracy of the model, the increase in the DEM cell size (considering other parameters being fixed) causes a drastic increase in modeling error. This amount of error in DEM-20 m is almost 5.5 times that of DEM-1 m. Therefore, the important point in debris flow modeling with RAMMS is to use a suitable DEM cell size to increase the accuracy of the model. According to the results, if the DEM cell size is less than 5 meters, the magnitude of error is not significant and can be ignored.

One of the factors influencing the changes in the morphology of desert areas is the frequency of wind blowing due to the relative poverty of wind blowing and the surface and covering cover in these areas. Wind transport of sand is a complex process that depends on factors such as wind speed, amount of bare soil, dry air conditions, soil grain size, vegetation, local and external air system, short-term discharge, extent of deforestation, in an area. Based on this, the activity of winds in carrying out erosion is significantly related to the climatic conditions of each region. Wind erosion in desert areas is seen in the form of sand dunes.The importance of sand dunes studies is due to their impacts on water and soil resources, flora and fauna, human infrastructure, and roads. Therefore, for the purpose of basic planning, monitoring the speed and direction of movement or the expansion of sand dunes, due to the damages caused by it and especially the preservation of natural resources and human projects and facilities, is of special importance in the management of desert areas.

In this research, wind characteristics, dust characteristics, soil moisture and its effects on Zabol region are investigated. To check wind speed and direction, the data of Zabol anemometer station were evaluated in Wrplot software. Then, the sand graph was drawn in SandRose-Graph software in order to check the indicators of sand movement. The changes of dust and AOD index of the region were extracted in the Erthengine system and MODIS satellite images in the period from 2012 to 2023. Changes in soil moisture index in the region were also monitored using SMAP satellite images in Arth Engin.

In this research, the predominant wind direction of the region was determined as northwest-southeast by examining the wind direction of Zabol station. On the other hand, examining the trend of wind speed changes at Zabol station shows that the average wind speed at Zabol station has been increasing over the past 56 years; So that the average wind speed has reached from 2.5 m/s per month in 1962 to about 4.8 m/s per month in 2018, which shows an increase of 2.3 m/s during this period. The amount of sand carrying potential (DPt) at this station is 2079/8, which is estimated to be high based on Freiburger's and Dean's classification of wind energy at this station. The variability index (UDI) of wind directions for Zabol station is in the low variability group with the classification of unidirectional and channelized winds, which greatly increases the intensity of erosion and dust production. The highest amount of displaced sand (DSF) in Zabol station indicates the amount of sand particles transported in the region.
In addition to examining the characteristics of the wind in the region, the changes in the dust index (AOD) and aerosol were also carried out using MODIS sensor images in the environment of Erth Engin from 2012 to 2023, and the results showed that the highest percentage of dust with a size greater than 55 microns and less than 47 microns in the summer of every year and with the decrease in surface humidity and the increase in temperature and the occurrence of 120-day winds in Sistan, also the examination of the percentage of dust changes in the air in the 5-year period from 2018 to 2023 showed a significant increase. which indicates an increase in the percentage of airborne particles due to the expansion of wind erosion in the region.
Next, the soil moisture of the region was monitored using the Smap satellite image series, including changes in the percentage of surface and subsurface soil moisture in the Zabol region in the Google Earth Engine environment and the time period from 2015 to 2023, and the results showed that the highest percentage of soil moisture is from February to April. And the lowest percentage of soil moisture is from July to September, which corresponds to the occurrence of 120-day winds in Zabol region.

The results obtained from this research show that the main cause of dust occurrence in Zabol region is the increase in the wind speed in the region in the long term and the increase in dust supply centers around the region, which, along with climate change and the decrease in rainfall and the occurrence of drought, in the scale Locally, the drying up of Lake Hamon as a result of the Afghan government's non-compliance with the 1351 Kabul agreement regarding the introduction of 850 million cubic meters of water per year into Lake Hamon has had a significant impact on this issue. Considering the location of the dried Hamon lake in the northwest and west of Zabol city, and the direction of the prevailing wind, it can be said that most of the dust particles transported to Zabol originate from this area. Therefore, the only solution to the current situation of Zabol can be the restoration of Lake Hamon and stabilization of the sediments on the bottom of Lake Hamon. On the other hand, the presence of channelized and dominant northwest-southeast in the region has provided the conditions for the construction of wind power plants in this region, considering the criticality of the country's energy, which is used with proper planning and investment for this issue.

Geodiversity is the heterogeneity of the non-living environment of the earth, which is the basis of most human activities and ecosystem life. The expansion of human activities and the destruction of this lifeless environment are the most important factors threatening the geosystem and ecosystem. The spread of kinds of human activities on the surface of the earth is considered as a threat to geodiversity and biodiversity. Most of the researches conducted for geodiversity assessment and human treats and destruction impacts have not been taken into consideration. Among the researches, only Betard and Paulvast (2019) evaluate geodiversity indices with indicators of human threats (desertification and land use) in an integrated manner in Brazil. In this study, areas with high geodiversity that are threatened by human activities have been introduced as geodiversity hotspots. The northern slopes of the Alborz mountains (Iran) are among the areas with high land diversity and extensive human activities in various economic and tourism sectors have caused many land use changes. Therefore, this research was conducted with the aim of quantitatively evaluating geodiversity and combining it with the index of human activities, in order to determine the sensitivity of geodiversity in the Babolrod catchment (Mazandaran province).

For the quantitative assessment of geodiversity, four main indexes of geology (lithology and faults), geomorphology, soil and hydrography (rivers and springs) were used and the number of elements were counted in square grids of 1.5 x 1.5 km. Then, the total values of six layers were calculated and the grid layer was converted into a point layer. These points were interpolated using the ordinary kriging method and the geodiversity map of the basin was obtained. To evaluate the level of human intervention and destruction in the landscape, the land use map of the basin was used. This map became the Hemerobi index. Based on this index, the amount of human intervention in land use is classified into seven classes. Classes one to seven represent completely natural state to very intense human impact, respectively (Walz and Stein, 2014). After performing steps one and two, the two geodiversity layers and the hemerobic index layer were multiplied together and the geodiversity sensitivity map of the region was obtained and classified into five sensitivity classes.

The geodiversity map of the catchment was classified into 5 groups based on the natural break method. The very low (4-11) and low (11-16) classes include a total of 53% of the area of the catchment and are mainly located in the northern parts of the region. High (18-23) and very high (23-31) classes include 22.3 and 1% of the catchment area, respectively, which are mostly observed in the central and southeastern parts. Among the indices in the geodiversity map, the geomorphology index with an average value of 44.5% has the highest proportion of values compared to other indices. The weighted values of the hemeroby index ranged from 1.6 (weak human impacts) to 5.36 (severe human impacts). The plain area in the north of the basin, which are affected by many human activities, have the highest score, and the central areas of the basin, which are dominated by dense forests, have the lowest score. The southern parts of the basin, which are covered by pastures, are in an medium condition. According to the geodiversity sensitivity map, 11.32% and 12.25% of the basin area were classified as very high (69-92) and high (55-69), respectively. Most of these areas were located in the south and east of the basin. Very high sensitivity class is located in the southern parts of the basin with pasture use and the eastern parts of the basin in the location of the Alborz Dam lake and its downstream, which is used for agriculture. The forest areas where there has been a lot of human intervention and clearing and destruction have been placed in the medium and high sensitivity class. The low sensitivity class (32-44) with 41.5% of the area of the basin has the highest distribution in the basin. This class is mainly located in the plain parts of the north of the basin and forest areas with high density and minimal human intervention. In order to further analyze the geodiversity sensitivity map, the correlation coefficient of this map was calculated with the type of soil erosion map. This coefficient was calculated pixel by pixel in ARC GIS software and the value of 0.81 was obtained, which indicates a good relationship between these two factors.

In the geodiversity sensitivity map at the regional scale, areas with high geodiversity and high threat index are identified as sensitive areas. This approach to geodiversity (preparation of geodiversity sensitivity map) can be used to create geoconservation plans and land use management at the basin scale by geoscientists, planners and decision makers in environmental management and developing effective strategies.

Statement of the Problem: Floods are a devastating natural disaster that can cause soil erosion, soil wastage, and damage to human infrastructure in flood-prone areas of watersheds. Therefore, it is crucial to predict and determine the amount of runoff production processes and its safe transfer to the outlet of the watershed. Various factors, including climatic and physiographic parameters, affect the conversion of precipitation into runoff. Climatic factors involve the intensity and duration of rainfall as well as the distribution of rainfall locations. Physiographic parameters include land use type, soil type, watershed area, basin shape, height, slope, direction, and type of drainage network. Therefore, several methods can be used to estimate the runoff generated by rainfall, and one of the commonly used methods in hydrology is the Soil Conservation Service (SCS) method. Furthermore, determining the spatial changes and correlation between the factors of runoff production and flooding can identify flood-prone areas. Therefore, this research utilized geographic information systems (GIS) to provide essential and fundamental information for obtaining direct runoff using the curve number (CN) method. The study aimed to estimate the height of excess rainfall runoff and analyze the spatial variations of runoff height and volume in the Sharganj watershed, Birjand. To achieve this goal, the SCS method was employed to estimate the amount of runoff generated by the maximum 24-hour rainfall in different return periods in the aforementioned watershed. Subsequently, the changes and spatial correlation of the values of the height and volume of the runoff were evaluated in the Sharganj watershed, Birjand.

This study estimated the amount of runoff produced from the maximum 24-hour rainfall in different return periods in the Sharganj watershed using the SCS method. To achieve this, the maximum 24-hour rainfall from surrounding stations was averaged using the IDW method. Next, the SCS method was utilized to estimate the runoff by combining land use maps and soil hydrological groups to prepare the curve number map. The basin runoff volume was then calculated for different return periods. Additionally, the spatial autocorrelation of the runoff height and volume in the 25-year return period was analyzed using the general Moran's index, and their clustering pattern was determined using Anselin Local Moran's Index.

The Sharganj watershed is primarily used for pastures and agricultural lands, with the former being located in hydrological group C. Despite this, rainfed and irrigated garden lands, mainly located in hydrological group B, have better permeability. Using ArcGIS software, land use maps and soil hydrological groups were combined to prepare a curve number map of the watershed. The results showed that the curve numbers of the sub-watersheds ranged from 68 to 79, with sub-watershed number 9 having the lowest curve number value (68) and sub-watersheds 22, 25, and 29 having the highest (79). The Global Moran's index values presented in Table 3 and Figure 10 showed that the spatial correlation of runoff height and volume had values of 0.1828 and -0.2694, respectively. The curve number decreased from west to east due to the presence of barberry gardens and irrigated agricultural lands. The spatial correlation map of runoff height values showed high-high (HL) clusters forming in the upstream parts of the basin, while low-low clusters (LL) were present in the downstream areas. These patterns were related to the amount of precipitation in the upstream part and the high slope of the upstream sub-watersheds. Meanwhile, the spatial correlation values of runoff volume indicated that the accumulation of runoff volume was higher in the sub-watersheds located downstream of the study area, with low formation of high-low (HL) clusters. This increase in flood volume occurred in the downstream sub-watersheds and adjacent to the outlet of the area. In general, the difference in the cluster pattern of runoff height and volume did not follow the same pattern, which depended on various factors affecting runoff production, such as the amount of precipitation in different parts and the difference in topography. It should be noted that the analysis was based on height and volume values in the 25-year return period, and the results can be expected to be similar for other return periods based on the curve number method.

The research findings suggest that the spatial changes in runoff height and volume components, which impact watershed response and flood producing procedures, are determined by various factors such as slope, land use, curve number, and soil hydrological group. Areas with high amounts of runoff are more susceptible to damages caused by floods and can be prioritized for management measures. Furthermore, the results indicate that the type of surface runoff control measures or flood volume control required will vary, providing valuable guidance for determining the appropriate damage reduction operations. Further studies analyzing the spatial correlation of height and runoff volume variables with other basin features and climatic factors could enhance the understanding of spatial changes. The formation of surface runoff is influenced by various factors related to rainfall and ground conditions, which could be considered in future research.