Mr Milad Heydari, Dr , Dr Ali Akbar Barati, Dr Taher Azizi Khalkheili,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: A major part of rural risk, such as production risks, economic risks, and severe climate changes, is related to agricultural risks, which have significant negative impacts on the agricultural sector. This study aimed to investigate the effects of risks and hazards of the rural ecosystem on the development of various types of rural tourism in the rural tourism area of Mahmoudabad County, located in Mazandaran Province, in order to examine the development of various types of rural tourism as a strategy for resilience and adaptation of villagers, as well as a preventive strategy in villages against economic, environmental, and social shocks, as well as reducing vulnerability and diversifying the rural economy.
Methods: The research method is applied in terms of purpose and descriptive (non-experimental) and correlational (variance matrix analysis) in terms of data collection method with the aim of showing the relationship between variables. The study population included all 88 villages in Mahmudabad city. The data collection tool was a researcher-made questionnaire and the respondents were the villagers. The structural equation modeling (SEM) method based on Smart-PLS was used to analyze the data.
Results:
The results of the research on prioritizing dimensions and hazard and risk items for rural ecosystem assessment show that economic, environmental, and social risks were ranked in priorities one to three, respectively. Based on the path coefficient (pc), only the direct effect of environmental pressure (with a path coefficient of 0.338 and a T-value of 2.467) was significant. About 30 percent of the changes in the development of tourism types are explained by the proposed model with the direct effect of environmental hazards and the indirect effect of economic hazards and social hazards.
Conclusions: As a general conclusion, the types of rural tourism in the region should be given serious attention as opportunity driven entrepreneurship and necessity driven entrepreneurship. In this regard, recognizing ecological values through education and long-term propaganda for the sustainable development of rural livelihoods with emphasis on the development of green tourism, ecotourism, and agrotourism is recommended
Engineer Sama Abdollahi Milani, Engineer Sama Rahmani, Doctor Javad Imani Shamloo,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: The study aims to evaluate the ecological, environmental, and economic services provided by urban vegetation within the El-Goli green network in Tabriz. Specifically, it focuses on assessing the role of green infrastructure in mitigating urban environmental challenges through carbon sequestration, air pollution reduction, and surface runoff management. The research seeks to provide insights that support informed urban planning and the sustainable expansion of green spaces.
Methods: This study is a quantitative research that employed library-based methods (literature review, definitions of urban green infrastructure, and expert opinions) and field observations, combined with statistical analysis using i-Tree software for data collection. Data analysis was conducted using a descriptive-analytical approach, and the results are presented in tables.
Evaluation Parameters: The ecosystem services assessed in this study include carbon sequestration and storage, air pollution reduction, and stormwater management.Assessment Parameters: Key ecosystem services evaluated include carbon capture and storage, air pollution reduction, and surface runoff management.
Results: The El-Goli green network in Tabriz sequesters approximately 75.84 tons of carbon annually.
The green network removes about 2,077 tons of air pollutants per year.
Among the pollutants analyzed, ozone was the most effectively removed, while carbon monoxide showed the lowest removal rate.
The findings underscore the significant role of the El-Goli green network in improving urban air quality and contributing to climate change mitigation.
Conclusions:
This study used i-Tree Canopy 7.1 to assess the ecosystem services of El-Goli Park in Tabriz from ecological and economic perspectives. The vegetation area was measured, and trees and shrubs were counted to estimate carbon storage, air pollutant removal, and surface runoff mitigation. Results showed that the park annually sequesters 75.84 tons of carbon, removes 2,077 kg of air pollutants, and mitigates 1.92 liters of surface runoff. Considering the software’s limitations, it is recommended that ecosystem productivity in the park and other urban green spaces be enhanced through the protection of valuable trees, increasing effective plant species, developing dense vegetation cover, and implementing bioretention networks.
Mr Azim , Moslem Savari, ,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: Risk assessment in tourism destinations plays an important role in maintaining tourist safety and environmental sustainability. Identifying potential threats such as natural disasters, overcrowding, cultural damage, and social hazards provides the basis for more accurate planning and more effective tourism management. The present study was conducted with the aim of assessing environmental risks in the tourist areas of Dezful County.
Methods: The statistical population included tourists from rural areas of Dezful County, which, according to the statistics of the Cultural Heritage Organization, are visited by more than 10 million people annually. The sample size was determined as 384 people using the Krejci and Morgan table, and sampling was carried out randomly. In this study, 33 villages in four districts of the county were examined. The data were analyzed using a questionnaire and confirmatory factor analysis.
Results: According to the results of the study, only the Choghamish district faces high political risks, and the other districts have a moderate threat in this area. In the area of financial and economic risks, the matter is different, and only the central district faces a moderate threat, and the other districts face a high level of threat. However, the most important result of this study was in the area of social risks, where all districts showed a low level of threat, which indicates appropriate security and comfort for tourists traveling to this city. The results of the study also show a moderate level of environmental risks in the Shahyoun, Sardasht, and Choghamish districts, and even in the central district, these risks are in the low priority range. The results of the confirmatory factor analysis of tourism risk reduction strategies in Dezful city were classified into information and educational factors, legal and security factors, precautionary factors, and infrastructure factors.
Conclusions: The present study showed that social risks in Dezful county are at a low level and the security of tourists is ensured. However, economic and environmental risks in some sectors require more attention and management. Implementing the proposed solutions can help improve the quality of the tourism experience and the sustainable development of the region.
Dr Komei Abdi, Dr Hematolah Roradeh,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: Floods are among the most significant natural disasters in Mazandaran Province, particularly in Sari County, where they cause widespread economic, social, and environmental damages each year. The main objective of this research is to identify and map flood hazard zones using machine learning algorithms, namely Random Forest (RF) and Support Vector Machine (SVM), and to apply an ensemble approach in order to enhance prediction accuracy and reduce model uncertainty.
Method: In this study, a set of spatial datasets including a Digital Elevation Model (DEM), land use/land cover derived from satellite imagery, geomorphological indices (slope, aspect, and drainage density), geological data, distance from roads and streams, vegetation index (NDVI), and climatic variables (precipitation and temperature) were collected. These datasets were processed using GIS and RS techniques and prepared for model training and validation. The models’ performance was assessed using evaluation metrics such as Accuracy, F1-score, AUC, and ROC curve analysis.
Findings: The results indicated that both RF and SVM demonstrated high performance in flood hazard mapping, as reflected by strong evaluation metrics. Moreover, the ensemble approach improved prediction reliability and reduced errors compared to single-model predictions. The generated maps revealed that a significant portion of Sari County falls within high and very high hazard zones, which overlap with are::as char::acterized by intense rainfall, high drainage density, and steep slopes.
Conclusion: This research highlights that machine learning algorithms, particularly when applied in an ensemble framework, are powerful tools for identifying flood-prone areas. The findings can serve as a scientific basis for urban planning, disaster management, and flood risk reduction strategies in Sari County and other comparable regions.
Dr. Malihe Erfani,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: Livestock grazing in the Hyrcanian forests is one of the oldest forms of traditional land use, practiced within locally defined areas known as customary systems. In contrast, formal forest utilization is conducted through management plans divided into compartments. This study aimed to examine the role of ecological factors in shaping the boundaries defined by local communities (customary systems) and by experts (compartments) in parts of the Nowshahr forests, including the Namkhaneh and Garazbon series.
Methods: The ecological factors analyzed included vegetation type, main and sub-rivers, ridge, ravine, hillsides, and aspect. Boundary maps of customary system and compartment were compared with ecological boundary maps in a Geographic Information System (GIS). Since roads play a determining role in compartment boundaries, their influence was also examined.
Results: Results showed that 90.02% of customary system boundaries aligned with ecological factors, while only 4.5 km did not. Moreover, 81.29 km and 85.2 km of compartment boundaries (equivalent to 90.22% and 94.56%) were determined by ecological factors, respectively, and by the combined effect of ecological factors and roads. In total, 8.81 km of compartment boundaries were not consistent with ecological factors, which decreased to 4.9 km when road influence was considered. Among ecological variables, vegetation type and aspect had the greatest effect on boundary formation. All major rivers contributed to defining boundaries, representing 17% of customary system boundaries and 9% of compartment boundaries. Less than one kilometer of roads did not coincide with compartment boundaries, while about 32% of compartment boundaries overlapped with roads.
Conclusions: These findings indicate that traditional knowledge used in defining customary system is rooted in a deep understanding of structural factors of ecology, whereas expert-designed compartment boundaries also incorporate management and accessibility considerations alongside ecological ones.
Fatemeh Arsalani, Bohloul Alijani, Sabereh Arsalani,
Volume 8, Issue 4 (1-2021)
Abstract
Dust fall means the dust that in the air fall down on the ground (Hai et al, 2008). it is important to study the extent of heavy metal contamination of dust fall due to their threats that could affect human health. Due to the fact that the metropolis of Tehran has a population of over eight million people and One of the major cities in the world is currently facing a severe air pollution problem. The purpose of the present study was to determine the level of pollution and health risk of heavy metals such as Cd, Cr, Cu, Ni, Pb in the dust falling of Tehran city. the Dust fallout samples were collected using Marble Dust Collector (MDCO) from 28 different locations across Tehran during the statistical period (2018/03/21- 2018/06/21). We used XRF analysis To identify and determine the concentration of heavy metals (Cd,Cr,Cu,Ni,Pb,Fe) in the collected dust. we used to spatial analysis to determine Dispersion of pollution levels and health risk in different Zone of Tehran city. In order to determine the level of pollution and Health Risk Assessment we used the pollution index (PI), integrated pollution index (IPI), Non-Carcinogenic Risk and Carcinogenic Risk. Based on the results of the calculations performed in the statistical period studied, the values of pollution index (PI) and integrated pollution index (IPI) are Pb> Cd> Cu> Cr> Ni, respectively. Accordingly, the regional trend of pollution from west to east is increasing. Therefore, Tehran's pollution index is high level of pollution in the most zone and and extremely high level of pollution in the eastern zone, which is a more worrying situation. Probably one of the reasons is the western winds, which are faster in the west than in the east. Also, Tehran's topographic pattern plays a role in this issue. Health risk assessment (HQ, HI, CR) showed that the contamination of the heavy elements studied was lower than the acceptable threshold for carcinogenic and non-carcinogenic risks. Therefore, it is not dangerous in terms of carcinogenicity. The risk of carcinogenicity and non-carcinogenicity in children and adults is higher in the southern and eastern zone of Tehran. Probably one of the reasons is the establishment of metal industries, cement production, sand mines and combustion processes in the south and west of Tehran metropolis.
Mr Mehrdad Karami, ِdr Mohamadreza Pourjafar,
Volume 8, Issue 4 (1-2021)
Abstract
The phenomenon of land-use change in the peripheral areas of Tehran Metropolis, particularly within the Lavasanat region, has transformed over the past two decades from a merely physical and economic process into a strategic issue in spatial governance, territorial resilience, and passive defense. This study aims to elucidate the institutional, spatial, and ecological mechanisms influencing land-use change and its consequences for the region’s spatial resilience, adopting an integrated approach and employing both qualitative and quantitative methods. Data were collected from three main sources: content analysis of legal and policy documents related to land management, semi-structured interviews with experts and local officials, and spatial analysis of land cover data using a land-use change prediction model. Findings indicate that land-use change in Lavasanat results from the simultaneous interaction of three levels of action: the degradation of ecological structures—which has reduced the land’s natural capacity to absorb and mitigate environmental hazards—, institutional weaknesses that have undermined land monitoring and control, and spatial concentration that has heightened exposure to risks. Concurrent with the sharp decline of agricultural lands and the loss of natural buffer zones, these transformations have weakened environmental functions, intensified physical vulnerability, and reduced the efficiency of passive defense.
Analytical results suggest that Lavasanat is undergoing a transition from a stable spatial system to a fragile and defenseless one. The process of land-use change in this region is not merely the outcome of demographic or economic pressures but rather a reflection of the disruption in spatial governance and institutional deficiencies in land management. Consequently, what appears outwardly as "development" has, in practice, led to a gradual process of "territorial defenselessness" and the erosion of both ecological and institutional resilience.
Halimeh Kargar, , Mohammad Saligheh, Mehry Akbary,
Volume 8, Issue 4 (1-2021)
Abstract
Conclusion
The results showed that the length of the precipitation period in the study area is 8 months (out of 213 systems, 60 systems were recorded in January and 50 systems were recorded in December). June, July, August and December did not have a comprehensive rainfall system. The difference in height between the Mediterranean Cyclone and the Arabian Anticyclone, i.e. the MAI index, was identified in 5 categories. The results showed that the higher the value of MAI index, the less rainfall systems and the higher the rainfall intensity. Most rainfall systems occur when the MAI index reaches 100 to 150 geopotential meters. In addition, the concentration of precipitation occurred in February when the MAI index reached 200 geopotential meters and above. In the continuation of the research, the difference between the Sudan Cyclone and Arabian Anticyclone, i.e. the SAI index, was also identified in 5 categories. The results showed that most of the systems occurred in the third category with a value of SAI index between 100 and 150 geopotential meters. Moreover, the results showed that the higher the value of the SAI index (, the lower the number of rainfall systems and the higher the average of rainfall systems.
Sharifeh Zarei, Bohloul Alijani, Zahra Hejazizadeh, Bakhtiar Mohammadi,
Volume 8, Issue 4 (1-2021)
Abstract
In this research, the most important synoptic patterns of widespread snowfall in the western half of Iran have been investigated. For this purpose, the data of current weather code and snow depth of 36 synoptic stations during the statistical period of 1371-1400, for the months of October to March, were received from the Meteorological Organization of the country. In order to investigate wide snowfalls, the days when more than 70% of the studied area saw snowfall at the same time were extracted as a wide day. In order to perform synoptic-dynamic analysis of wide snowfalls in the western half of Iran, the classification method using cluster analysis was used and maps of representative days were drawn, including atmospheric temperature, moisture flux, geopotential height, tovai, front formation, jet stream, omega index, and orbital and meridian wind data. Trend analysis was also performed using the Mann-Kendall test. The results showed that 4 models justify the widespread snowfall in the studied area in the best way. According to the results in all the models, at sea level, the collision of cold and dry air of northern latitudes with warm and humid air of southern latitudes has caused the formation of frontal fields in the western half of Iran. At the level of 500 hectopascals, the intensification of the meridional currents in the western winds caused the creation of closed centers and as a result the flow changed in the direction of the westerly winds, and the location of the western half of Iran in the east of Naveh Al-Aghti and Sardchal has provided the necessary conditions for air to rise. Also, there was no trend in the number of snow days in the western half of Iran at the significant levels tested. But; The number of snow days has been decreasing over time. In general, it can be concluded that due to the warming of the earth and climate change, the number of snowy days has decreased and these changes have led to a significant shortening of the snow season.
Dr Amir Saffari, Dr Ali Ahmadabadi, Mr Amieali Abbaszadeh,
Volume 8, Issue 4 (1-2021)
Abstract
Subsidence is one of the most important natural hazards that has affected many plains of the country in recent years. Eyvanakey plain in Semnan province is among the plains that have faced this danger. Due to the importance of the subject, in this research, the evaluation of the subsidence risk and the estimation of the subsidence rate in this plain have been done. In this research, Sentinel 1 radar images, Landsat satellite images and SRTM 30 meters high digital layer are used as the most important research data. The most important research tools are GMT, ArcGIS and Super Decisions. Also, Fuzzy-ANP logic and SBAS time series models have been used in this research. This research has been done in two stages, in the first stage, the assessment of the subsidence risk and in the second stage, the estimation of the rate of subsidence in Eyvanakey Plain. Based on the results, 251 square kilometers of the study area (equivalent to 58.5% of the area) has a high and very high risk of subsidence, which mainly corresponds to the southern areas of the Eyvanakey Plain. Also, the results of the SBAS time series method have shown that the Eyvanakey plain has subsided between 28 and 533 mm during a period of 6 years. Considering that, the high risk class has the highest amount of subsidence in the study area, so it can be said that there is a strong relationship between the subsidence risk classes with radar images and the accuracy of the results of the subsidence risk classes is confirmed.
Dr Maryam Ghasemi, Mis Monir Sayah, Mis Atena Vatankhah,
Volume 8, Issue 4 (1-2021)
Abstract
Rural areas, due to their close relationship with the natural environment and having limited capabilities, are highly vulnerable in the face of crises. With the establishment of village councils as a rural management institution in the country's villages, a suitable opportunity was provided to follow up, establish and continue the programs related to safety and crisis management in the rural community. Based on this, the aim of the current research is to measure the performance of fifth and sixth grade villagers in rural crisis management. The studied area is the central part of Bojnord city in North Khorasan province. The research method of the present study is descriptive-survey. In terms of the practical purpose and from the perspective of time, it was carried out in two periods of 1397 and 1401. The data collection tool is a researcher-made questionnaire. According to the description of the tasks of the rural organization, 14 tasks have been defined in the field of crisis management for villagers in three stages before, during and after the crisis. Out of a total of 77 inhabited villages, the villagers of 44 villages in the central part of Bojnord city, a total of 88 villagers have answered the questions of the questionnaire at two points in time. Data analysis was done using independent two-sample t-test and one-sample t-test in SPSS software. The results showed that 99% of the surveyed villages are exposed to floods and 95% are exposed to earthquakes. In order to compare the performance of the villagers according to the duties of the village organization, in the fifth (2018) and sixth (2024) periods, the t-test of two independent samples was used. The difference between the average performance of the villagers in the previous, during and after stages and in total the performance of the villagers in the fifth and sixth periods is average and not significant. Finally, due to the absence of a significant difference between the average performance of villagers in the fifth and sixth period, the average performance of 88 villagers in both periods was investigated with the theoretical median
Alireza Rahimi Mahmoodabadi, Navid Saeedi Rezvani, Iraj Ghasemi,
Volume 8, Issue 4 (1-2021)
Abstract
introduction: Resilience is the key to urban sustainability, and by reducing vulnerability, it creates a sustainable environment for cities and plays a fundamental role in reducing urban vulnerability to environmental hazards.
Methods: The present research method is descriptive-analytical and applied in terms of purpose. The aim is to measure the resilience level of District 2 of Karaj and identify its strengths and weaknesses in facing environmental hazards. The research combines data from statistical documents, written reports, and questionnaire data obtained from surveys. The statistical sample consists of 30 experts related to crisis management in District 2 of Karaj, selected through the snowball sampling method. Data analysis was performed using mean statistics, standard deviation, and factor analysis.
Results: The results indicate that enhancing the resilience of this area through improving the quality of physical infrastructure, better construction management, adherence to architectural standards, and urban planning principles can reduce vulnerability and create a sustainable and resilient environment. Additionally, the evaluation of building sustainability shows that the average index in District 2 was 4.45. The average indices for spatial organization were 4.43, geographical characteristics were 4.57, and infrastructure sustainability was 4.8. This indicates a favorable status of resilience and sustainability indices in District 2 of Karaj.
Conclusions: Factor loadings show that the coefficients are above 0.6, confirming the validity of the resilience indices. Therefore, the urban resilience and sustainability of the region can be evaluated as favorable to highly favorable.
Dr Mehdi Safari Namivandi, Mr Alimohammad Gholami, Dr Parastoo Ghaforpuranbaran, Mr Kamyar Emami,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: Land subsidence is one of the hazards that affect many plains in Iran, including the plains of Semnan province. Given that the risk of subsidence is associated with many harmful effects, this study evaluates the subsidence situation in the urban area and urban outskirts of Garmsar and analyzes the factors affecting its occurrence.
Methods: In this research, Sentinel 1 radar images, Landsat satellite images and information related to groundwater resources of the region have been used as the most important research data. The most important research tools have been ArcGIS, GMT and Google Earth Engine software. In this research, first, using the SBAS time series method, a map of the subsidence rate of the region has been prepared and then its relationship with the decline of groundwater resources and the type of land uses of the region has been investigated.
Results: Based on the results obtained, the study area has subsided between 12 and 79 mm during a one-year period (from January 2021 to January 2022), with the highest rate of subsidence in the southern outskirts of Garmsar city.
Conclusions: The results of this study also showed that the annual decline in groundwater resources in the southern wells of the region was more than 2 meters, and given that the highest rate of subsidence was also related to these areas, it can be said that the main reason for the subsidence of the region was the decline in groundwater resources. Also, based on the results, the development of human constructions, especially heavy structures, has been effective in intensifying the subsidence that has occurred.
Jafar Amin Moghadam, Mohamadreza Baharestanfar, Mohammad-Hossein Jafari,
Volume 8, Issue 4 (1-2021)
Abstract
Objective: This study investigates the legal challenges impeding local governance in Iran from enhancing urban resilience. Despite constitutional recognition, local bodies are hampered by a centralized system, legal ambiguity, and a lack of independence. The research aims to systematically analyze these challenges and propose reform solutions to improve the relationship between central and local authorities.
Methods: The research employs a descriptive-analytical method, utilizing a review of legal documents and a comparative analysis with international experiences to dissect existing legal issues and propose reforms.
Results The findings reveal a significant gap between the ideals of participatory democracy and good governance, and Iran's reality. An institutionalist approach shows that while formal structures like councils exist, they are undermined by a weak participation culture, lack of financial and decision-making autonomy, and ineffective accountability mechanisms. This prevents the realization of true democracy and effective local governance, rendering citizen participation merely instrumental.
Conclusions: In conclusion, Iran's local governance is semi-functional and inadequate for crisis management. A multi-level reform agenda is essential, including constitutional revision, a comprehensive local governance law to ensure autonomy, and the creation of sustainable financial resources. Enhancing transparency and institutionalizing citizen participation are also critical. However, these legal and structural reforms will only succeed with a fundamental shift in political culture towards accepting responsible decentralization.
Mrs Masoumeh Alidadi, Professor Bohlol Alijani, Dr Mohammadhossein Nasserzadeh, Professor Zahra Hejazizadeh,
Volume 9, Issue 1 (5-2022)
Abstract
Comparative analysis of snowfall events in Iran with emphasis on the location of the polar plateau and remote connection patterns
Abstract
Extream snowfall event that may occur at any time during the cold season, has significant social and economic implications. Therefore, the economic and social consequences of these events reveal the importance of identifying the synoptical mechanisms associated with the extream snowfall events. In order to achieve this goal, using daily precipitation and temperature data during the statistical period of 1951-1 2016 and based on multiple criteria, the two three-days extream snowfall events were identified during February 7-9, 1972 and February 2-4, 1988. After selecting samples, a statistical analysis of the teleconnection indices was done and then, using the NCEP-NCAR reanalysis data, the combined patterns of surface and lower, middle and lower troposphere were plotted in the form of three-days mean. Results obtained from analysis of teleconnection indices and their correspondence to the synoptic patterns indicate the weakening of the tropospheric polar vortex and its division into multi-centers in the periods of extream snowfall events. In the event of February 7-9, 1972, though the centers were moved to mid-latitudes, but they are not completely out of the Arctic and to some extent maintain their position in this area. In February 2-4, 1988, the vortex centers have shown a more equatorwards displacement towards the mid-latitudes that the emergence of negative phases of the NAM and AO represent such a situation. However, in both events, the strong and main center of the polar vortex is located in the eastern hemisphere and therefore in a state close to Iran. The weakening of the sub-tropical jetstream in the eastern hemisphere, especially in the Mediterranean, has resulted in the transmission of potential vorticity tabs to mid-latitudes. The equatorwards progress of these tabs has led to the formation of the trough in the western and eastern Mediterranean regions that accompany with a ridge between them, led to the formation of omega bundle patterns and split flow, respectively, in the events of February 1972 and 1988 in this geographical area. The southern boundary of the progress of the troughs has specified by index contour of the edge of the vortex by 552 gpdam, that extends to the southern part of Iran and in the February 1972, event compared with the pattern of the February 1988, had the more-equatorwards progress toward the middle latitudes, and as a result, over Iran.
Keywords: extream snowfall event, teleconnection, polar vortex, the edge of the vortex, blocking patterns.
Tahmineh Chehre Ara,
Volume 9, Issue 1 (5-2022)
Abstract
Investigating the role of atmospheric circulation patterns in the severe air pollution in Esfahan
Introduction
The atmosphere is a dynamic system in which a large number of physical and chemical processes occur simultaneously. Studying the dynamics and transmission of pollutants in the atmosphere using atmospheric patterns is one of the important topics in this field. Atmospheric patterns simulate the occurrence of different processes within the atmosphere and their interactions. Using an atmospheric model also requires comparing the results of the model with field and laboratory experiments. This helps in understanding the occurrence of chemical and physical processes in the atmosphere as well as evaluating the implementation of a suitable model. Laboratory measurements provide valuable information while at the same time visualizing and describing atmospheric properties and atmospheric composition at specific time and space intervals. An atmospheric model provides a complete picture of the evolution of spatial and temporal variations in atmospheric pollutants at different altitudes. Understanding atmospheric dynamics can be understanded by combining measurements and integrated modeling with using synoptic systems in periods with pollutated air. Therefore, in this study, it has been attempted to analyze the atmospheric factors that cause severe pollution in Esfahan and the relationship and mechanism of the atmosphere at the time of occurrence of this phenomenon.
Data and methods
In this study, three datasets including pollution data recorded at air pollution stations, digital atmospheric data and high atmospheric stations were used. The air pollution data are from three stations of Laleh Square, Azadi and Bozorgmehr which were obtained from Esfahan General Environmental Protection Office. The pollutants include carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone and suspended particulate matter (PM10), which have been prepared and processed daily for a 12-year statistical period (1995-2005). To study atmospheric conditions were used re-analyzed data from the National Center for Environmental Prediction (NCEP / NCAR) include sea level pressure, geopotential height, vertical velocity (Omega), wind orbital components (U), and meridian wind ( V) was used for different levels of atmosphere.
The above atmospheric data were obtained from the University of Wyoming site for the study days, including air temperature, dew point temperature, wind direction and intensity, and atmospheric stability and instability conditions (based on skew-t curves). In this study, a Lagrangian model with the capability of tracking particle backward in different levels of atmosphere called HYSPLIT was used to investigate the days associated with severe pollution.
Results and discussion
The results show that the highly pollutated days of the city of Esfahan can be explained by the four synoptic patterns. The occurrence of days with extremely severe pollution in Esfahan, rather than being rooted in local factors, is due to the interaction of local conditions with atmospheric circulation at the regional scale. In other words, the city of Esfahan will only experience extremely polluted days when the atmospheric circulation of the atmosphere provides conditions for increased concentrations of pollutants.
The main causes of the occurrence of days associated with maximum contamination can be attributed to Subtropical high latitude and its progression to higher latitudes. This circulation system contributes to the occurrence of highly polluted days on most days, either directly or in combination with other atmospheric systems.
The role of local factors such as the formation of inversion layer and the increase of atmospheric thickness due to the dominance of high pressure systems in the region can also be considered to exacerbate the conditions.
The use of suspended particle backward models and the study of atmospheric thermodynamic relationships have provided a deeper and more accurate understanding of the mechanisms dominating the occurrence of pollutants in Esfahan.
The results of this method showed that the occurrence of highly polluted days in the city of Esfahan can not be attributed to urban pollutants such as industrial factories of automobiles and so the influx of particulate matter from different areas has caused higher intensity pollution.
Conclusion
The results showed that four factors and patterns prevailed in the middle of the atmosphere at the time of the most severe days pollution in Esfahan. The results of the PSI values in each pattern showed respectively from pattern of one to four, is 221, 238.6, 203 and 281.
The synoptic conditions can be attributed to the presence of tropical high pressure, which is accompanied by a layer of temperature inversion in the lower levels of the atmosphere and the middle troposphere.
Strength of negative vorticity above 700 hPa and continued surface convergence to this altitude have made the nature of the summer atmosphere clearly observed in the pollution event in the city, which has been enhanced by strong anomalies.
On the other hand, the output of the HYSPLIT model showed that the occurrence of highly polluted days in the city of Esfahan could not be detected in urban pollutants such as automobile industrial plants and. But, the influx of particulate matter from different areas has made the pollution more intense, and the influx of dust particles has exacerbated this hazard.
Keywords: Air Pollution, PSI Index, Atmospheric Regional Circulation Patterns, HYSPLIT Model, Esfahan
Manijeh Ahmadi, Mohsen Kalantari, Mostafa Mohammadi,
Volume 9, Issue 1 (5-2022)
Abstract
Introductions
Today, various social ills such as addiction, cultural issues and problems have been added to the issues raised in the past and require extensive studies and planning in this area to preserve the small human capital of rural settlements and be used for sustainable rural development. The present study has spatially analyzed the effective factors for drug addiction and abuse. Today, various social ills such as addiction, cultural issues and problems have been added to the issues raised in the past and require extensive studies and planning in this area to preserve the small human capital of rural settlements and be used for sustainable rural development. In recent years, drug abuse has increased worldwide, so that now all countries in the world are incurring significant costs as a result of the damage caused by this phenomenon. Drug abuse has incurred enormous social and economic costs through its devastating effects on human health and the increase in crime and mortality in society, and as a result has become a major threat to societies. There is no specific agreement on the root causes of drug abuse, so that the factors associated with it are numerous and varied, including individual contexts, family characteristics, and social and environmental factors. The present study has spatially analyzed the effective factors for drug addiction and abuse.
Research Method
The type of research is applied and the nature of the research is descriptive-analytical. Independent variables in this study are physical and demographic factors in the study village. The dependent variable of this study is the situation of addiction and drug abuse in Dizajabad village. The validity of the research indicators was reviewed and modified by the professors and the reliability value was calculated based on Cronbach's alpha of 0.784. The statistical population of the present study is villages at risk of addiction and drug abuse. This village was identified through interviews with law enforcement experts and statistics available in this organization as well as unofficial statistics. The number of these villages includes four villages (Sayan (Mahdieh town), Dizajabad, NoghtehBandi and Choreh Nab) which were selected as a sample village using the lottery method of Dizajabad village. The study population in Dizajabad village includes people who are addicted to drugs and abuse in Dizajabad village, which have been collected through irregular interviews, as well as for comparison and assessment between addicts and other people. The questionnaire was completed in all residential units where people lived and the Cochran's formula was used for accurate sampling.
The baseline map was used to perform the analyzes. Using Cochran's formula, 115 residential units belonging to people with addiction and drug abuse were selected as a sample. In order to analyze descriptive data from Excel software and also for correlation between physical characteristics, population of people with addiction and drug abuse, Spss software and Human Whitney and two-group T tests were used in Arc Gis / Arc map environment. Hot Spot Analysis, kernel density estimation and standard deviation ellipse tests were used.
Interpretation of results
Findings show that the spatial distribution of addiction and drug abuse in Dizajabad village is not evenly distributed and are mostly concentrated in the northwest and southeast, which are in these two areas due to the high density of residential units. . According to the tests of hot spots of addiction and according to the studied items, the two southeastern and northwestern parts of the village have hot spots and the standard deviation ellipse in this map indicates that its direction is northwest, southeast. This direction is influenced by the shape of the village. The pattern of drug distribution in the village also indicates that it is concentrated in two parts, northwest and southeast. The median center indicates that the southern and to some extent the southeastern part are more addicted than the other parts. The reason for the increase in the points of addiction and abuse in the two mentioned parts is the density of the residential unit and the existence of a network of winding and unbalanced passages, especially in the southeastern part. Centers of addiction and drug abuse by kernel density estimation method show that the two parts of the northwest and southeast of the village are more affected by drug addiction and abuse.
Keywords: Spatial distribution, Drugs, Addiction, Suburban villages, Zanjan Township
Shamsollah Asgari, Tayeb Raziei, Mohamadreza Jafari, Ahmad Hosini,
Volume 9, Issue 1 (5-2022)
Abstract
Introducing the appropriate model of oak forest and drought relations
in Ilam province
Introduction
The forest ecosystems of the Zagros vegetation region have a very long history of exploitation in various
forms. The material of the Zagros vegetation region is Iranian oak. In recent years, a significant
proportion of oak forests have dried up or have experienced drought. Although the main cause of drought
in these forests has not been determined yet, in the preliminary studies, factors such as climate change,
increasing dust, increasing drought periods, pest infestation and disease, high user changes have been
cited as reasons for drought in the Zagros forests. (Hosseinzadeh and Pourhashemi, 1396). Iran's location
in the arid and semi-arid zone of the world (sub-tropical region) has often been associated with
fluctuations in climatic and atmospheric elements and under the influence of atmospheric currents,
synoptic patterns, irregularities in precipitation and temperature patterns (Rahmati, 2016; 1383).
Comparison of the effect of climatic variables on healthy masses and affected by the decline of oak in
Khorramabad city based on rainfall and temperature data using Pearson correlation coefficient, on annual
growth rings of oak trees Effectiveness of drought of oak trees from both series In general, healthy trees
have been more affected by monthly and seasonal temperatures and have shown the highest coefficient of
correlation with the temperature of the region (Naseri Karimvand et al., 2016). , And the Standardized
Rainfall Index (SPI) and the correlation between these two indicators in assessing and monitoring drought
in different areas of Isfahan province, the results showed that NDVI plant index can be a good alternative
to climatic indicators in drought assessment and monitoring) with the conclusion and colleagues, 2011:
79).
Data and Method
So from SPI and NDVI indicators and Moran index and statistical regression statistics and satellite
images of Modis and Landsat have used to analyze the relationship between dieback of Ilam forests and
happened drought in the region. The precipitation data of 93 rain gauge stations were analyzed during the
statistical period and according to the dry coefficients of SPI index, drought zoning layers of Ilam
province were prepared for two time series of 2000 to 2009 and 2010 to 2019. Greenery's raster layers
were prepared from Modis satellite imagery for the mentioned time series. The results of analysis of
Moran's statistical showed a significant correlation between the SPI index and the NDVI index in spatial
dimensions. By a simple random method, 143 points of oak dieback with dimension of 30 m 2 , which each
point was equivalent to a pixel-size, were recorded with a GPS device, and by simulating in satellite
imagery, the droplet layer of oak dieback was extracted.
Result and Discussion
What is debatable about the results of the implementation of methods for obtaining drought ranges and its
relationship with oak drought points or masses is that the results of the models show a statistically close
and direct relationship between drought and oak drought. . The general trend of oak drought and drought
in these two decades has been from the southeast to the northwest of Ilam province, with increasing
temperature and decrease in rainfall in the southern and eastern regions of the province and increasing
rainfall and decrease in temperature in the central and northwestern regions of Ilam province. The data of
the synoptic stations are consistent. Analysis of satellite imagery and declining greenery in the models
although the study was aimed at meteorological drought and precipitation fluctuations, but spatial
changes of arid points and masses in the province were adapted to field visits and human intervention,
especially in the southeast with agriculture. Under the rubble and the remnants of the dried trees, the ax
has been placed on the roots of these trees, and this trend is spreading in almost other parts of the arid
areas of the province. Therefore, due to the irregularity in the pattern of precipitation and temperature of
the research country (Rahmati, 2016; Zandi Army, 2004) and the effect of monthly and seasonal
نشریه تحلیل فضایی مخاطرات محیطی، سال نهم، شماره 1، بهار 1401 2
temperature on the growth and decline of oak trees in the study (Naseri Karimvand et al., 2016) and other
related research and The flooding situation in the basins of Ilam province, the rainfall, the impermeability
of the soil and their erosion, and finally the lack of moisture in the months before the oak trees grow in
the soil and the increase in temperature in the dry season, which leads to reduced humidity and eventually
greenery. Variables affecting oak drying in linear regression are not responsive, but more accurate results
will be obtained in multivariate regression, although regression analyzes are spatially empty, and X and Y
represent a one-way, quantitative analysis based on the number of dried trees with pixel counts. Drought
range is measured which this defect in SPI method despite its spatial and statistical analysis using Moran
statistical index due to non-compliance in the coefficients of this index with the range of changes in
Moran statistical analysis in statistical analysis is a more appropriate explanatory coefficient than The
regression models showed but at a lower level than the NDVI method it placed. The advantage of NDVI
method with Moran statistical analysis is the relationship between pixel and pixel, ie in spatial analysis,
all pixels that have green changes have been analyzed in the same domain of spatial changes with oak
trees. High results and higher statistical explanation coefficient were obtained than other models.
Conclusion
Although linear regression between extracted oak dieback points with SPI and Moran statistical indicators
was significant, but the relationship between NDVI index and Moran statistic has the effect of
independent variable of drought trend in spatial and temporal dimensions on the dependent variable
process of oak drought with spatial analysis. And nonlinear regression has a more appropriate and
accurate statistical significance and explanation. So this method as desirable method has been introduced
for analyzing of drought and oak dieback.
Keywords: Ilam province, oak forest drought, drought, Moran index
Hossein Kianpour, Soolmaz Dashti, Roshana Behbash,
Volume 9, Issue 1 (5-2022)
Abstract
Vulnerability assessment of Miangaran wetland ecosystem
To support the proper management of ecosystems, vulnerability analysis of ecosystems is very important. Vulnerability analysis of ecosystems provides information about weaknesses and capacity of the studied ecosystem for recovery after damage. Considering the degradation status of Miangaran wetland, vulnerability evaluation of this wetland is one of the most important management methods in the region. For this purpose, in this study, after identifying and evaluating the threatening factors of Miangaran wetland, these factors were scored using evaluation matrices. Then, the interaction between these values and threatening factors was examined and the vulnerability of wetland values was obtained by multiplying the scores of all studied factors. Finally, management solutions were presented to deal with the most important threatening factors. According to the results, the most vulnerability is to the hydrological and ecological values of the wetland. The highest effects of threats on the ecological value are also on the birds of Miangaran wetland. The results of the evaluation of Miangaran Wetland show that this wetland has a high potential for ecosystem functions of the wetland. These functions have been neglected in the planning and managing of wetlands at the local, regional and national levels. As a result, ecosystem-based management is suggested as the best management approach. The management in these areas should take action to prevent the vulnerability of Miangaran wetland. Also, the vulnerability evaluation method used in this study can provide a good understanding of the relationship between wetland functions and the resulting services for the management of the ecosystem of Miangaran Wetland.
Key words: Miangaran wetland, ecosystem management, vulnerability assessment
Dr Hassan Lashkari, Dr Zainab Mohammadi,
Volume 9, Issue 1 (5-2022)
Abstract
Synoptic analysis of the changes trend of the share of systems due to the Sudan low
In the cold period of the Persian Gulf coast during 1976-2017
Introduction
In the Ethiopian-Sudan range forms the low pressure system without front in the cold and transition seasons that is affecting the climate of the adjacent regions by crossing the Red sea. Based on the evidence in the context of Iran, studying Sudan low was first begun by Olfat in 1968. Olfat refers to low pressures which are formed in northeastern Africa and the Red Sea and then pass Saudi Arabia and the Persian Gulf, enter Iran, and finally, cause rainfall. The most comprehensive research specifically examining Sudan low, was the work carried out by the Lashkari in 1996. While he studying the floods that occurred in southwestern of Iran, he was identified Sudan low by the most important cause of such flooding and he explained how they are formed, and how these low-pressure systems were deployed on the southwest of Iran.
Materials and methods
The study period with long-term variations was considered from 9.5 to 11 years based on solar cycles. Precipitation data for 13 synoptic stations are considered above 5 mm in south and southwestern Iran. With three criteria were determined for the days of rainfall caused by each type of atmospheric system. The visual analysis of high and low altitude cores and geopotential height at 1000 hPa pressure level (El-Fandy, 1950a; Lashkari, 1996; 2002) were considered based on the aim of the study. Accordingly, the approximate locations of activity centers, as well as the range of the formation and displacement of the Sudan system were initially identified based on the location of the formation of low and high-pressure cores. Then, the rainy days due to the Sudan system in January were separated from the precipitation of the other atmospheric system.
Results and discussion
According to the selected criteria in the forty-year statistical period, 507 precipitation systems were identified with different continuities that led to precipitation in the northern coast of the Persian Gulf. The pattern of independent Sudan low rainfall was responsible for 77% of the precipitation in the Persian Gulf. Decade frequency share of Sudan low was lower in the first decade (16%) compared to the next three decades. This system of rainfall was more activated during the second and third decades compared to the first decade. However, rainfall changes were not evident in the mid-decade. Independent Sudan low precipitation provide 25% and 27% of the cold season precipitation of the Persian Gulf during the second and third decades respectively. In accordance with the 24th solar cycle, at the end of the study period, the Sudan low was more effective on the Gulf coast than ever before. During this decade, 125 cases of Sudan low rainfall was recorded for the Persian Gulf. Thus, the frequency of Sudan low during the fourth decade was about 31%, which was higher than in the rest of the decade. Overall, the Sudan low rainfall was repeated 151 times for 2 days rainfall, during the statistical period studied. This Precipitation has increased over the last decades compared to other periods.
Conclusion
The severe variability of rainfall along the timing and location of the permanent Persian Gulf coasts can have a significant impact on the economic and agricultural behavior of the Gulf population in the three provinces of Ahwaz, Bushehr and Hormozgan.The purpose of this study was to evaluate the precipitation changes due to Sudan low in the Persian Gulf coastal region during the cold period. The results of this study showed that the role of integration patterns in influencing the precipitation of the Persian Gulf coast has decreased with the strengthening and further activation of the Sudan low system during the last two decades. That way, about 77percent of the region's rainfall is provided by independent Sudan low. At the end of the course (in accordance with 24th solar cycle activity) the Sudan low system was more active than before. Although the Sudan low activity was different at each station during the period studied, but in the historical passage incremental and decade's positive behavior of Sudan low was common to all stations. Evaluation of changes in rainfall duration shows that the pattern of precipitation with 2days duration is more frequent than the patterns of one to several days.
Keywords: Sudan low- Solar cycle- Persian Gulf.