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Mr Abolghasem Firoozi, Dr Akram Bemani, Dr Malihe Erfani,
Volume 10, Issue 1 (5-2023)
Volume 10, Issue 1 (5-2023)
Abstract
Introduction:
The growth rate of urbanization during the recent decades of metropolises has had many destructive effects on the urban environment, among which we can mention the change of temperature of surfaces and local climates. The increase in the urban population, the rapid growth of industrialization and the increase in the concentration of pollutants in the lowest level of the atmosphere have affected the severity of the city's heat islands. Land surface temperature (LST) is a key variable to control the relationship between radiant, latent and sensible heat flux. Analyzing and understanding the dynamics of LST and identifying the relationship between it and changes of human origin is necessary for modeling and predicting environmental changes. The heat of urban surfaces is affected by various characteristics of urban surfaces such as color, surface roughness, humidity level, possibility of chemical compounds, etc. In addition, the changes between LST in a city and its surrounding area are due to surface changes, heat capacity and topography. Since the surface temperature regulates the temperature of the lower layers of the atmosphere, it can be considered as a weather indicator and an important factor in the urban environment. Changes in land use by changing the features of the surface cover such as the shape of the constructed areas, the amount of heat absorption, building materials, surface albedo and the amount of vegetation lead to changes in the temperature of the earth's surface. Barren lands with soil cover, on the contrary, increase the surface temperature of the earth. Climatic characteristics at the time of satellite image imaging also play a role in the extent and intensity of urban cold islands, so that satellite imaging in the middle of hot summer days shows urban cold islands better. The innovation of the research is in the large area of the investigated area, which includes eight urban areas, in order to examine the pattern of temperature changes on a wider level.
Materials and methods
Considering the rapid development of urban and industrial areas in the Ardakan-Yazd plain in recent decades, this study aims to investigate changes in the surface temperature pattern using Landsat 7 and 8 satellite images for both winter and summer seasons. It was done in 2002 and 2019. In addition, the relationship between land use/land cover and surface temperature was also investigated. Geometrical correction of satellite images was done using topographic map 1/25000 of Mapping Organization and atmospheric correction using FLAASH method in ENVI software. Algorithms used to obtain land surface temperature for Landsat 7 images were single-window method and for Landsat 8 images, the Landsat Science Office model was used. Land use/land cover layers related to the years 2002 and 2019 were used, and central statistical profiles and LST distribution were extracted for pasture, agricultural land, blown sands, industrial areas, rock outcrops and cities. In addition to examining temperature changes in different uses, it is also possible to compare over time.
Results and discussion
The results of this study showed that the area of cold islands and thermal islands in winter and summer of 2002 is not much different, so that in winter 10.8 percent and in summer 10.4 percent of the area were cold islands and thermal islands in winter 9.02. It was 8.5% of the region in summer, while this difference is huge in 2019. Thus, 9.4% of the area in winter and 12.1% in summer are covered by cold islands, and thermal islands are 8.3% in winter and 1.6% in summer. Changing land use and increasing the size of urban and industrial areas and reducing agricultural land is one of the main reasons for the increase in cold islands. The survey of land use/land cover changes between these years showed that the extent of urban areas increased from 22,045 to 23,714 hectares, and industrial areas also grew by about two times, from 4,615 in 2002 to 8,187 hectares in 2019. However, during this period, the area of agricultural land has decreased from 1161 hectares in 2002 to 793 hectares in 2019. Also, the results show that the percentage of heat islands is higher in winter than in summer. The main reason for this can be the much less vegetation covers in the winter than in the summer, because the vegetation cover acts as a moderator of the earth's surface temperature. Cold islands are formed in the built-up areas in the winter and summer. From 2002 to 2019, the extent of cold islands decreased in winter and increased in summer, while the extent of thermal islands decreased in winter and summer. Also, the results of the validation section of the single-window method and the model of the Landsat Science Office in calculating LST showed that for both summer and winter seasons, Landsat 8 has a higher accuracy than Landsat 7, and the LST estimation model is based on the exclusive method of this The Landsat series of satellites (Landsat Office of Science model) has a higher efficiency than the single-window method.
Conclusion
The results showed that cities play an important role in changes in the temperature pattern of the earth's surface, and the phenomenon of urban cold islands is not exclusive to big cities in hot, dry and semi-arid regions, but also occurs in medium-sized cities. The temperature variability of eight cities located in the Ardakan-Yazd plain with the land use/cover of the suburbs also showed that the cities are colder than the suburbs in both winter and summer seasons. This study showed the role of vegetation in hot and dry areas in reducing LST and also provided evidence for the change in the degraded state of pastures in this area.
Keywords: Urban climate, Land use, Land surface temperature, surface urban cool island (SUCI), surface urban heat islands (SUHI)
Mrs Halimeh Shahzaei, Dr Mohsen Hamidianpour, Dr Mahsa Farzaneh,
Volume 10, Issue 2 (9-2023)
Volume 10, Issue 2 (9-2023)
Abstract
Spatial analysis of Iran's climate change from the point of view of sensible heat flux and latent heat flux by Bowen method
Halimeh Shahzaei; Ms.c student of Climatology, Departement of Physical Geography, University of Sistan and Baluchistan, Zahedan, Iran.
Mohsen Hamidianpour[1]; Associate Professor, Departement of Physical Geography, University of Sistan and Baluchistan, Zahedan, Iran.
Mahsa Farzaneh; Ph.D Graduated. Climatology.
Abstract
Sensible heat flux and latent heat flux are among the variables that are closely related to temperature and humidity and show heat transfer on a surface. So, their changes can be considered related to changes in temperature and humidity. In this regard, the current research aims to analyze and reveal the climatic changes of Iran by examining the course of changes in sensible heat flux and latent heat and the ratio between the two. For this purpose, NCEP/NCAR reanalysis data including sensible and latent heat flux during the period 1948-2020 was used in Iran. Bowen coefficient was calculated from the ratio of these two heat fluxes. Interpolation methods were used for their spatio-temporal analysis. In addition, by using the non-parametric methods of Mann-Kendall and Shibsen, spatial and temporal changes were also investigated. The first part of the results showed that, spatially, the Bowen coefficient is a function of latitude and roughness. And in terms of time, the lowest value corresponds to the month of January and the highest value corresponds to the month of July. The results of the second part show that the Bowen coefficient has a positive trend over time. Its upward trend indicates an increase in the dryness coefficient of the country. So that this situation can be seen in the positive trend and increase in temperature.
Keywords: climate change, Bowen coefficient, global warming, spatio-temporal analysis.
[1]. Autehr corespound:Email: mhamidianpour@gep.usb.ac.ir
Popak Dananiyani, Ehsan Soureh, Bakhtiyar Mohammamdi,
Volume 10, Issue 2 (9-2023)
Volume 10, Issue 2 (9-2023)
Abstract
Thunderstorms are one of the atmospheric phenomena; when they occur, strong winds are often reported along with heavy rains and lightning. In many cases, their occurrence is accompanied by a lot of financial and human losses. This research was carried out to investigate the Spatio-Temporal of thunderstorms and understand their trends in Iran. For this purpose, the monthly data of the number of days of thunderstorms in 201 Synoptic stations in Iran from the beginning of establishment to 2010 were used. First, the frequency of monthly and annual occurrence of thunderstorms at Synoptic stations in Iran was calculated. Also, the trend of thunderstorms was investigated based on the non-parametric Mann-Kendall test and the amount of decrease or increase of this phenomenon was determined with the help of the Sen’s slope estimator test. The results of this research showed that thunderstorms occur in all areas of Iran. However, the frequency of this phenomenon is more in the North-West, South-West, and South-East of Iran than in other parts. In terms of time, in every month of the year, part(s) of Iran is the center of the maximum occurrence of thunderstorms. For example, in the winter of southwest, south, and southeast of Iran, in the early spring of west and northwest of Iran, and the late spring of the southeast of the country, the main focus of this phenomenon has been. In the summer, northwest to the northeast of Iran and southeast and south of Fars province are the main centers of thunderstorm formation. At the beginning of the autumn season, the coasts of the Caspian Sea to the north of the Persian Gulf and towards the northwest of Iran, and in November and December, the southwest and west of Iran were the main places of occurrence of this weather phenomenon. Other results of this research showed that the trend of thunderstorms was not similar in Iran. This phenomenon showed a significant increasing trend (more than 1 day per year) at the 99% confidence level in the northwest, southwest, and southern half of Kerman province. Also, a significant decrease (0.7 days per year) was estimated in the southeast and a large part of central Iran. In other parts of Iran, a decrease or increase in thunderstorms has been observed in a scattered manner, although the amount was not significant at the 99%, 95%, and 90% confidence levels.
Fateme Emadoddin, Dr Ali Ahmadabadi, Seyed Morovat Eftekhari, Masumeh Asadi Gandomani,
Volume 10, Issue 3 (9-2023)
Volume 10, Issue 3 (9-2023)
Abstract
Introduction: Land subsidence is one of the environmental hazards that threatens most countries today, including the majority of Iran's plains (Ranjabr and Jafari, 2010). Damages caused by subsidence can be direct or indirect. Infrastructural effects are direct and indirect effects of subsidence, but economic, social and environmental effects are indirect effects of subsidence (Bucx, et al., 2015). The environmental effects of subsidence are related to other effects of subsidence, including the infrastructural, economic and social effects of subsidence. The southwest plain of Tehran is considered one of the most important plains of Iran due to its large areas of residential, agricultural and industrial lands from various aspects, especially economic, political and social. The subsidence of the Tehran plain was first noticed by the measurements of the country's mapping organization in the 1370s. Since 2004, the responsibility of investigating this phenomenon in the plains of Tehran was entrusted to the Organization of Geology and Mineral Explorations of the country. Although several researches have been done in the field of subsidence factors, amount and zoning. In the field of estimation of subsidence and changes in water level, spatial correlation of subsidence with changes in water level and estimation of vulnerability due to subsidence according to the density of population, settlements and facilities in the southwestern plain of Tehran has not been done.
Methodology: In the current research, we will analyze and estimate the spatial regression of the subsidence phenomenon by InSAR technique with water level changes from 2005 to 2017, as well as the environmental effects of subsidence in the southwest plain of Tehran by using Quadratic analysis method (O’Sullivan and Unwin, 2010). The criteria map of the current research is overlapped using the ANP method (Ahmedabadi and Ghasemi, 2015) weighting and finally with the SAW method (Emaduddin et al., 2014) in the Arc GIS 10.8 software, and the vulnerability map due to land subsidence in the study area is prepared.
Results: The average subsidence in 12 years is about 9.9 cm per year. Average subsidence has occurred in four main zones. Maximum and minimum subsidence have been observed in B (near the Sabashahr) and D (in east of plain) zones respectively. The results of the interpolation of the depth of the underground water in the study area indicate that the general trend of increasing the depth from the south (10 meter) to the north (more than 90 meter) of the plain. The results of spatial correlation showed that there is a significant direct relationship between the spatial layer of the average subsidence rate of Tehran Plain and the spatial data of the underground water level, and the R value is equal to 0.61. The distribution map of the underground water depth of the study area in the form of Quadrat analysis shows that in the main part of the plain, the depth of underground water is at an average level. The general trend of changes in the level of underground water is decreasing from northwest to southeast and is in 5 levels. The distribution of the networks shows that the rivers have three linear trends from north and northwest to south; their dispersion is mostly in the center of the study area. The flood rate is higher in the central plain networks. In study area, there are important arterial roads such as Tehran-Qom highway, Tehran-Saveh highway and Tehran Azadegan highway. The southern and northeastern areas of the study area are urban settlements such as Islamshahr, the 18th and 19th districts of Tehran Municipality and other residential areas such as Sabashahr. The major part of the region has fertile soil and the occurrence of subsidence can have negative effects on the fertility and texture of the soil in the study area. The results of vulnerability analysis due to subsidence show that there are 5 vulnerability classes in the study area including very low, low, medium, high and very high.
Conclusions: All in all most of the study areas (central, northern and western networks) are in medium, high and very high vulnerability. About 14,600 hectares of the study area are in medium vulnerability. Which is continuous from the west to the east of the study area. Most of the urban infrastructures are moderately vulnerable to subsidence. About 17,000 hectares of the southwestern plain of Tehran are very vulnerable. That more than half of the area of this area is covered by settlements and urban infrastructures. Therefore, the phenomenon of subsidence causes irreparable damage to the settlements and infrastructures in the southwest plain.
Methodology: In the current research, we will analyze and estimate the spatial regression of the subsidence phenomenon by InSAR technique with water level changes from 2005 to 2017, as well as the environmental effects of subsidence in the southwest plain of Tehran by using Quadratic analysis method (O’Sullivan and Unwin, 2010). The criteria map of the current research is overlapped using the ANP method (Ahmedabadi and Ghasemi, 2015) weighting and finally with the SAW method (Emaduddin et al., 2014) in the Arc GIS 10.8 software, and the vulnerability map due to land subsidence in the study area is prepared.
Results: The average subsidence in 12 years is about 9.9 cm per year. Average subsidence has occurred in four main zones. Maximum and minimum subsidence have been observed in B (near the Sabashahr) and D (in east of plain) zones respectively. The results of the interpolation of the depth of the underground water in the study area indicate that the general trend of increasing the depth from the south (10 meter) to the north (more than 90 meter) of the plain. The results of spatial correlation showed that there is a significant direct relationship between the spatial layer of the average subsidence rate of Tehran Plain and the spatial data of the underground water level, and the R value is equal to 0.61. The distribution map of the underground water depth of the study area in the form of Quadrat analysis shows that in the main part of the plain, the depth of underground water is at an average level. The general trend of changes in the level of underground water is decreasing from northwest to southeast and is in 5 levels. The distribution of the networks shows that the rivers have three linear trends from north and northwest to south; their dispersion is mostly in the center of the study area. The flood rate is higher in the central plain networks. In study area, there are important arterial roads such as Tehran-Qom highway, Tehran-Saveh highway and Tehran Azadegan highway. The southern and northeastern areas of the study area are urban settlements such as Islamshahr, the 18th and 19th districts of Tehran Municipality and other residential areas such as Sabashahr. The major part of the region has fertile soil and the occurrence of subsidence can have negative effects on the fertility and texture of the soil in the study area. The results of vulnerability analysis due to subsidence show that there are 5 vulnerability classes in the study area including very low, low, medium, high and very high.
Conclusions: All in all most of the study areas (central, northern and western networks) are in medium, high and very high vulnerability. About 14,600 hectares of the study area are in medium vulnerability. Which is continuous from the west to the east of the study area. Most of the urban infrastructures are moderately vulnerable to subsidence. About 17,000 hectares of the southwestern plain of Tehran are very vulnerable. That more than half of the area of this area is covered by settlements and urban infrastructures. Therefore, the phenomenon of subsidence causes irreparable damage to the settlements and infrastructures in the southwest plain.
Nabi Mohamadi, Behrouz Sari Saraf, Hashen Rostamzadeh,
Volume 10, Issue 3 (9-2023)
Volume 10, Issue 3 (9-2023)
Abstract
Nowadays, due to global warming, drought and the occurrence of cold periods and heat stress, the study of climatic variables is very important. Therefore, in this research, the long-term forecast of temperature changes in northwest Iran in the base period (1985-2014) and three periods of the near future (2021-2050), the medium future (2051-2080) and the distant future (2100- 2081) was paid. For this purpose, 2 extreme temperature indices including Warm spells duration index (WSDI) and cold spells duration index (CSDI) and Maan-Kendall trend test were used to check the changes. To predict the changes of the profiles in the future period after evaluating 7 general circulation models (GCMs) from the sixth report model series (CMIP6) from two optimal models under three socio-economic forcing scenarios including SSP1-2.6, SSP3-7.0 and SSP5-8.5 was used. The spatial distribution of the trend of changes in the Warm spells duration index (WSDI) in the base period showed that its maximum core is located in the south and southwest of the region, and its amount decreases by moving towards the north and northeast. Spatial changes of the Cold spells duration index (CSDI) are characterized by its maximum cores in the western regions and around Lake Urmia and minimum cores in the central and northern regions of the study area. According to the results, the average Warm spells duration index (WSDI) and of the Cold spells duration index (CSDI) are equal to 5.53 and 3.80 days per year, respectively, and the maximum and minimum Warm spells duration index (WSDI) are 1.8 and 2.7 days, respectively Piranshahr and Parsabad stations and the maximum and minimum and the Cold spells duration index (CSDI) are also 5.7 and 1.32 days corresponding to Zarineh and Marivan stations. Examining the trend of changes also showed that in most stations, the WSDI index has an increasing trend, and this trend has become significant in some stations, but the CSDI index has a decreasing trend and is not significant in any of the stations. The evaluation of different models with different error measurement indices also showed that MRI-ESM2-0 and MPI-ESM1-2-L models have the best performance in simulating temperature extreme in the studied area. The distribution of changes in the future period also showed that the WSDI will increase in most stations and based on all three scenarios, especially the SSP5-8.5 scenario, but the CSDI trend will decrease in most stations and based on the SSP3-7.0 and SSP5-8.5 scenarios will be significant.
Tajdin Karami, Ali Shamaei, Fateme Mohebi,
Volume 10, Issue 4 (12-2023)
Volume 10, Issue 4 (12-2023)
Abstract
Abstract
Ecological resilience is a concept that implies the reversibility of ecological structures and functions against the shocks experienced. The northern zone of Tehran, as the most important ecological support of this city, has undergone many land-use changes in recent decades. The present study has analyzed the role of land-use change in the ecological resilience of green infrastructure (as one of the pillars of ecological structure) in District 1 of Tehran Municipality. This study is an applied one in terms of purpose and is considered a descriptive-analytical one in terms of the method used. In this study Landsat satellite data (1976-2021) were used to detect the changes of interest, and landscape metrics were used to analyze the ecological resilience conditions. Based on the results of this study period, the Number of Patches (NP) has significantly increased and the Class Area (CA) has decreased during the period covered by this study. These changes indicate the fragmentation process and loss of structural cohesion of the green patches. The measurement results for the connectivity metrics (ENN and GYRATE) also showed a small connectivity between the green patches in the area. In addition, the results for CONTAG (Contagion Landscape metrics) measure indicated that, due to low connectivity, the transmission rate is low. Therefore, it can be said that the green infrastructure of the region has lost its structural cohesion in the face of land-use change, and as a result, the expected ecological functions and services have also failed. According to the results, the green infrastructure of the study area is vulnerable to land-use changes and their ecological resilience has been significantly reduced.
Dr Ali Zangiabadi, Mr Fazllollah Karimi Ghotbabadi,
Volume 10, Issue 4 (12-2023)
Volume 10, Issue 4 (12-2023)
Abstract
Economic resilience to natural disasters, which is actually how economic capacities affect disasters, is one of the issues that must be considered in any society. It is noteworthy that the type of attitude towards economic resilience and how to analyze it on the one hand, plays a key role in how to recognize the current situation resilience and its causes, and on the other hand also affects policies and measures to reduce risk and how to deal with it. The purpose of this study is to rank the economic resilience of new urban Habitations in the Isfahan Metropolitan against earthquake risk. Due to the studied components and the nature of the subject, the approach of this research is "descriptive-analytical". The statistical population of this study includes 6 new urban Habitations of Shahin shahr, Majlesi, Sepahan shahr, Fooladshahr, Baharestan and Shahid Keshvari. This research is applied in terms of purpose and in the research literature section, information has been collected through the library method. According to the results obtained from ASI in this study, the new urban Habitations of Baharestan, Majlesi, Fooladshahr, Shahid Keshvari, Sepahan Shahr and Shahin Shahr have the first to sixth ranks in terms of economic resilience to earthquake risk, respectively. In order to reduce the adverse effects of earthquake risk, pay attention to the economic capacity of the studied Habitations and reduce the economic risk factors in each community, economic resilience should be considered to avoid financial losses caused by these possible accidents.
Mrs Mozhgan Shahriyari, Dr Mostafa Karampoor, Dr Hoshang Ghaemi, Dr Dariush Yarahmadi, Dr Mohammad Moradi,
Volume 11, Issue 1 (5-2024)
Volume 11, Issue 1 (5-2024)
Abstract
Flash floods are one of the most dangerous natural events and often cause loss of life and damage to infrastructure and the environment. This research investigated the occurrence of the most intense continuous monthly floods (October-March) from 1989 to 2021. Precipitation data from 115 synoptic stations were selected. Then, the total rainfall of 1 to 9 days was sorted according to intensity. Using Minitab statistical software and the Andersen-Darling index, heavy rains were extracted based on the 95th percentile. Then, based on the criteria of the highest and lowest number of rainy days, the highest and lowest accumulated rainfall, the wettest and driest months were determined. Considering the three criteria of intensity, continuity, and rainfall coverage, the strongest storms in the wettest months were selected. The data used for synoptic analysis include the average sea level pressure data, the height and vertical component of the wind at 500 hPa, the wind and humidity field specific to the pressure levels 925, 850, and 700 hPa, and the horizontal moisture flux values specific to the pressure level 925, 850 and 700 hPa. The probability of the occurrence of atmospheric rivers was identified by the moisture flux extracted from the specific, meridional, and meridional wind components. The results showed that the storms of October 27-31, 2015, November 5-7, 1994, December 12-16, 1991, January 11-15, 2004, February 3-9, 1993, and March 13-15, 1996 were the strongest in the wettest months. During the storms of October, November, February, and March, moisture has been transported from the southwest of the Red Sea by atmospheric rivers to the western, southwestern, southern, and southeastern regions of Iran.
Dr Mehdi Safari Namivandi,
Volume 11, Issue 1 (5-2024)
Volume 11, Issue 1 (5-2024)
Abstract
Geotourism is one of the important pillars of tourism, which plays an important role in the economic and social development of regions, and this issue is doubly important in border regions. Considering that one of the ways to create security in the border zone is the economic development of the region, therefore, the development of geotourism in the border zone of the country is important. Considering the importance of the issue, in this research, the effects of geotourism development in creating sustainable security in Marivan city have been analyzed. In this research, the 30-meter height digital model of SRTM, the results of interviews and library studies have been used as research data. The most important research tools are ArcGIS, Expert Choice and SPSS. Also, in this research, Comanescu models, AHP and SWOT model were used. According to the intended goals, this research has been carried out in several stages, in the first stage to identify and evaluate geosites, in the second stage to analyze the effects of geotourism development on the goals of sustainable development and regional security, and in the third stage to identify effective factors. The development of geotourism has been discussed. The evaluation results of the identified geosites based on the Comanescu model have shown that the geosites of Marivan city have a high potential for the development of geotourism, which can be paid attention to with economic development, environmental development, infrastructure development and finally, it should be associated with the stable security of the region. Also, the results of the SWOT model have shown that the existence of rare geosites with a weight of 0.08, the lack of long-term development plans with a weight of 0.08, the creation of stable security in the region with a weight of 0.091, and the seasonality of employment with Weight 0.058, respectively, are considered as the most important strengths, weaknesses, opportunities and threats of geotourism development in Marivan city.
Khabat Derafshi,
Volume 11, Issue 1 (5-2024)
Volume 11, Issue 1 (5-2024)
Abstract
Coastal areas are constantly changing physically and ecologically, depending on natural and human factors. The natural causes of coastline changes are assessed in three ways: short-term changes including the effects of up and down currents, long-term changes including climate change, periodic storms and waves, and accidental changes including sudden natural events. Today, coastal tourism is considered as one of the important factors in the development of coastal areas. In this regard, the Caspian Sea, with many tourist attractions such as lush forests, accessible foothills and mountains, historical monuments and appropriate welfare facilities, benefits from the sea and beaches. The coastal area of Babolsar City, due to its many facilities and capabilities to attract tourists, much of which is due to natural and environmental attractions, every year, hosts a large number of tourists who come to this area to take advantage of its facilities and attractions, including the beautiful beach and very beautiful forests. This coastal area because its dynamic nature, is exposed to permanent erosion and variability due to processes such as river, wind, tectonic, wave and tide and marine transgression-regression in the area causes the destruction of coastal facilities and recreational places. Therefore, any planning to change the land use and construction in this coastal area should be considered in terms of the sea water fluctuation impacts on the shoreline position. Coastal environmental degradation as a result of Caspian Sea water level fluctuation are very probable and human behaviors in non-optimal choice of the land use locate intensify these losses. Coastal tourism, as one of the coastal land uses is heavily influenced by fluctuations in sea level in both marine transgression-regression statuses.
Email Kamal Omidvar, Email Rohollah Yousefi Ramandi, Email Hajar Toofani,
Volume 11, Issue 3 (12-2024)
Volume 11, Issue 3 (12-2024)
Abstract
Air pollution can have serious negative effects on human health, including cardiovascular and respiratory diseases. Monitoring and controlling air pollutants is very important to protect public health and the environment. Like many developing countries, Iran is facing air pollution, especially in its big cities and industrial cities. One of the powerful tools in air pollution monitoring is remote sensing methods. The aim of this study is to use relatively high-resolution satellite data to monitor air quality and air pollution using Sentinel-5 (Sentinel-5P) sensor images. In this study, a comprehensive monitoring based on the values of some of the most important air pollutants (including AI, O3, NO2, SO2, CH4 and CO) has been done using Sentinel-5 satellite images for Iran in 2019-2023. The results of this research showed that the emission of carbon monoxide and sulfur dioxide gases had a decreasing trend (in the months of June as an example of the examined month), but nitrogen dioxide gas, methane gas, ozone gas and aerosols had an increasing trend during the month. from June 2021 to 2023. In general, air pollution is more serious in the northern parts of the country, especially in big cities and several large urban gatherings. In this study, it was investigated how the levels of six air pollutants in Iran vary and differ from June 2019 to 2023. Another important result of this research is that the total amount of air pollution in 2020-2023 has faced an increasing trend compared to 2019. Also, the monitoring by Sentinel-5 satellite images shows that in recent years, Tehran has had the most polluted air in terms of carbon monoxide, nitrogen dioxide, sulfur dioxide and suspended particles (dust). Also, changes in the concentration of pollutants do not follow a specific pattern. It was also found that the GEE system is able to process a large amount of data in a very short time with high accuracy.
Ali Akbar Shamsipour, Faeze Shoja, Fatemeh Amrayi,
Volume 11, Issue 3 (12-2024)
Volume 11, Issue 3 (12-2024)
Abstract
The purpose of this study is to investigate one of the supporting services of the ecosystem, called habitat quality, and to assess the spatial vulnerability of natural landscapes in the city of Khorramabad using the InVEST habitat quality module. To achieve this objective, it is essential to identify the sources of threats, the relative weight of each threat, the maximum distance of its effect in space, the types of habitats, and the sensitivity of each to the source of the threat. In addition, one of the most important inputs of InVEST is the land use/land cover (LULC) of the study area. The Local Climate Zone classification method has been used for the creation of this map. Finally, the model generates spatial distribution maps of habitat quality and degradation across the landscape by combining LULC and different threat sources. The findings indicated that the city, airport, and highway factors are the most destructive threat factors to all habitats with an average score of 0.51, 0.345, and 0.33, respectively. Compared to other LULC, water, dense trees, and scattered trees suffered the most destruction, with sensitivity ratings of 0.47, 0.39, and 0.36, respectively. The results also revealed that habitat quality in Khorramabad is at a medium to low level, and the habitat quality is in very good condition in only 3% of the landscape area.
- Ghazale Rafiee, - Aida Maleki, - Yaser Shahbazi, Asghar Molaei,
Volume 11, Issue 3 (12-2024)
Volume 11, Issue 3 (12-2024)
Abstract
Natural biological crises are a constant threat to human societies; Therefore, it is considered important to be prepared to control and prevent such disasters. In dealing with such urban crises, addressing the category of non-pharmacological interventions against infectious diseases can be a way forward. Therefore, the aim of the current research is to find the main effective indicators in the epidemic and to explain the environmental components resulting from the interaction and correlation of the relevant measurable indicators at the locality level based on previous environmental studies.
In this research, in order to obtain a community of opinion about effective indicators in epidemiological crises, a systematic search was first conducted using the keyword of pandemic resilience. For this purpose, several widely used databases such as Web of Science, Scopus and Elsevier were searched between 2013 and 2023. After checking the quality of the conducted researches, 42 indicators were selected. Further, in order to find out the underlying variables and identify the basic factors or criteria in order to explain the correlation pattern between the observed variables, the exploratory factor analysis method was used and SPSS version 26 software was used to analyze the data. Data from 118 Tabriz neighborhoods were used for exploratory factor analysis. After collecting the data, the process of change, standardization has been done to prepare the data and convert the raw data into percentage, growth rate, average and ratio. Then, the status of urban resilience components against epidemic diseases was calculated and normalized separately based on factor load for each neighborhood. Finally, the results were illustrated using Arc GIS software.
The findings of the research indicate that 42 indicators affecting the spread of epidemic diseases at the level of localities can be re-categorized into 8 components of accumulation, diversity and design, social factors, density, economic factors, health infrastructure, environmental pollution and green spaces. Also, based on the findings, it can be said that the condition of most of the components in the neighborhoods of Tabriz city is at an average level.
Based on the results, the effects of environmental factors on the transmission of Covid-19 are differentiated spatially. These components represent more than 82% of the changes in effective environmental factors.
Arastoo Yari Hesar, Vakil Heidarysarban, Bahram Imani, Samaneh Sarani,
Volume 11, Issue 4 (2-2025)
Volume 11, Issue 4 (2-2025)
Abstract
he spread of Covid-19 in the rural areas of the country has caused more dangers due to the common rural cultures, and the ignorance and lack of efficient management of this crisis in the villages has caused irreparable consequences for these areas. In such cases, the existence of social capital can be very vital in creating national consensus and successful policies to pass this critical stage. Leading research is applied in terms of purpose and based on descriptive-analytical nature. To determine the sample size of villagers, using Cochran's formula, from the total of 6903 households in sample villages, 362 households were calculated as sample households to complete the questionnaire. In order to investigate the effects of social capital on economic and social indicators that are effective in reducing the vulnerability of the outbreak of Covid-19 in the border villages of Sistan, a wide range of indicators was determined, and from the one-sample T-test and the analysis of variance of the regression model to measure the The evaluation of the effects of social capital on socio-economic indicators effective in reducing the vulnerability of the outbreak of Covid-19 in the border villages of Sistan was used. The results of the research showed that the higher the level of people's participation and their trust towards each other, the higher the level of responsibility and knowledge of people, it has a positive role and effect on social and economic indicators in order to reduce the vulnerability of the spread of the covid disease. has had 19
Spatial and Temporal Analysis of Precipitation Concentration and Its Zonation in Mazandaran Province
Dr. Mohammad Hossein Nasserzadeh, Dr. Ali Reza Karbalaee, A Master's Student Maryam Ghaderi Rastaghi,
Volume 11, Issue 4 (2-2025)
Volume 11, Issue 4 (2-2025)
Abstract
Precipitation concentration denotes the temporal and spatial distribution of precipitation within a watershed, and has a substantial influence on hydrology and water resource management. This study examines the spatial and temporal patterns of precipitation concentrations in Mazandaran Province. Precipitation data from eight meteorological stations covering the period from 2002 to 2021 were used, and the Precipitation Concentration Index (PCI) was employed for data analysis. The findings revealed that the precipitation concentration in this province exhibited significant spatial and temporal variation. The highest PCI values were recorded in the western regions, particularly in Babolsar and Nowshahr, indicating high concentrations of precipitation during specific seasons. Conversely, the eastern region displayed a more uniform precipitation distribution. Seasonal analyses confirmed that spring was the least rainy season and autumn was the wettest. Additionally, Inter-annual variations in PCI indicated an increasing trend at some stations, suggesting a growing concentration of precipitation in recent years. Spatial analysis of PCI patterns also indicated that the southwestern and eastern regions of the province, influenced by topographic factors and distance from the Caspian Sea, experienced relative precipitation concentration during specific months. In contrast, the northern and northwestern regions, which are affected by Mediterranean weather systems and recent climate change, demonstrate an irregular and seasonal distribution of precipitation. The findings of this study underscore the necessity of considering spatial and temporal variations in precipitation concentrations in the management of water resources and hydrological processes in Mazandaran Province. The observed increasing trend in PCI highlights the need to develop adaptive strategies to address the challenges posed by extreme precipitation events and prolonged dry periods.
- Mahmoud Roshani, - Mohammad Saligheh, - Bohlol Alijani, - Zahra Begum Hejazizadeh,
Volume 12, Issue 1 (8-2025)
Volume 12, Issue 1 (8-2025)
Abstract
In this study, the synoptic patterns of the warm period of the year that lead to the cessation of rainfall and the creation of short to long dry spells were identified and analyzed. For this purpose, the rainfall data of 8 synoptic stations were used to identify the dry spells of the warm season for 30 years (1986 to 2015). The average daily rainfall of each station was used as the threshold value to distinguish between wet and dry spells. Then, according to the effects of dry spells, they were defined subjectively and objectively with different durations. Thus, 5 numerical periods of 12 to 15, 15 to 30, 30 to 45, 45 to 60 and more than 60 days were identified. By factor analysis of Geopotential height data at 500 hPa, 4 components were identified for each period and a total of 20 components for 5 dry spells. Therefore, 5 common patterns control the stable weather conditions of dry spells. Most dry days are caused by subtropical high-pressure nuclei, which have a wide, even, dual-core, triple-core arrangement. The effect of subtropical high pressure on the dryness of the southern coast of the Caspian Sea is quite evident. Other dry days were caused by southerly currents, weakening of northern currents, and the trough Anticyclones’ area. Also, the anomaly map of the components days at the 500 hPa level showed that the anticyclones and cyclones correspond to the positive and negative phases of the anomalies, respectively.
Dr Maryam Ghasemi, Mr Hadi Ebrahimi Darbandi, Mrs Mitra Yarahmadi,
Volume 12, Issue 1 (8-2025)
Volume 12, Issue 1 (8-2025)
Abstract
Drought is one of the most important challenges faced by pastoralists around the world. This phenomenon can have significant negative effects on livestock health, production, and livelihoods. However, pastoralists can adapt to drought and reduce its negative effects by adopting various strategies. Semi-nomadic people in Darbandi, Kalat-Naderi County, have been facing drought since 2007 due to their livestock farming. Since livestock farming has profound impacts on the lifestyle and livelihoods of these communities, the present study examines their experience in facing drought and identifies their management strategies in these conditions. The research method is qualitative and the research tool is in-depth interviews with 20 semi-nomadic people in Darbandi, Kalat-Naderi. Sampling was purposeful and carried out until theoretical saturation was reached to ensure that a wide range of perspectives and experiences were collected. The data from the interviews were analyzed using a qualitative grounded theory approach to extract key patterns and concepts. According to the findings, the semi-nomadic Darbandi people of Kalat County have adopted various strategies in the face of drought, which are classified into four categories: rangeland and grazing management strategies, livestock nutrition management, water consumption management, and livelihood diversification. These results can be used as a basis for formulating better policies in the field of crisis management and rural development. Also, these results can be used for more effective planning to reduce the vulnerability of nomads to drought.
Mehranjani Mohammad Soleimani, Tahereh Nemati, Tajeddin Karami, Ahmad Zanganeh, Taher Parizadi,
Volume 12, Issue 1 (8-2025)
Volume 12, Issue 1 (8-2025)
Abstract
Aging is one of the most prominent indicators of demographic decline that most modern societies experience. At this stage of demographic decline, alongside a decrease and stabilization of mortality rates, birth rates also sharply decline. The development of technology and the mechanization of tasks, the improvement of quality of life and health-related indicators, individual-centered lifestyles, and increased economic inflation are significant factors in this issue. Iran is also among the countries on the verge of entering the stage of demographic decline. However, the intensity of this trend varies in different regions of the country. This article examines and analyzes the state of aging in the neighborhoods of the metropolis of Tehran. This research falls into the category of applied research in terms of purpose and is descriptive-analytical in terms of method. The research is based on the census data from 2016 and utilizes spatial statistical analyses. The positive values of Moran's autocorrelation analysis for each of the indices: aging (0.664), old-age dependency ratio (0.644), youth ratio (0.653), aging ratio (0.664), and aging index (0.665) in the neighborhoods of Tehran indicate a clustered pattern. This means that the issue of aging is more acute in some neighborhoods and areas of Tehran. Accordingly, the density of the elderly population is higher in most neighborhoods of the central and northern parts of the city. The final result shows that the distribution of the elderly space follows the logic of the social macro-ecology of Tehran and is relatively consistent with its natural-social topography. Furthermore, the spatial analysis of aging in the neighborhoods of this city shows that although all neighborhoods generally grapple with the issue of aging, planning and management should be based on the patterns and nature of the spatial distribution of this issue.
Saeid Shabani, Behrooz Mohseni, Aiding Kornejady, Akram Ahmadi, Hassan Faramarzi, Esmaeil Silakhori,
Volume 12, Issue 1 (8-2025)
Volume 12, Issue 1 (8-2025)
Abstract
Deforestation is one of the primary challenges and environmental threats facing forest ecosystems, including the Hyrcanian forests, and occurs under the influence of various natural and anthropogenic drivers. This study aimed to model the probability of deforestation occurrence within the Loveh forest management district located in northern Iran. The dataset comprised 104 documented deforestation points and 14 explanatory variables, derived through spatial analysis using GIS and environmental, topographic, and anthropogenic data. To assess the relationships among variables and predict the likelihood of deforestation, two statistical models were employed: logistic regression and the Generalized Additive Model (GAM). The results revealed that the GAM outperformed the logistic regression model, achieving a higher Kappa coefficient (0.84) and Area Under the Curve (AUC) value (0.956), and providing a more realistic spatial distribution of deforestation risk. The most influential variables included distance from roads, slope, wind effect, and elevation. Based on the GAM output, approximately 20% of the study area was categorized as high and very high risk. These findings underscore the pivotal role of access infrastructure, human pressure, and climatic factors in accelerating deforestation processes. The results of this study can serve as a scientific basis for prioritizing conservation interventions, reassessing road development policies, and enhancing spatial planning for sustainable forest management in northern Iran.
Dr Saleh Arekhi, Mr Habib Allah Kour, Somia Emadaddian,
Volume 12, Issue 46 (9-2025)
Volume 12, Issue 46 (9-2025)
Abstract
Reducing the emissions caused by deforestation and forest degradation REDD is a strategy to moderate climate change, which is used to reduce the intensity of deforestation and greenhouse gas emissions in developing countries. In the last few decades, drastic changes in land use have caused a significant decrease in Hyrkan forests located in Mazandaran province. For this purpose, the aim of this study is to investigate the changes in land use and its prediction for the year 2050 using the Markov chain and the REDD project to reduce carbon dioxide emissions for the cities of Nowshahr and Chalus. Using the images of TM and ETM+ sensors of Landsat satellite, a land use map has been prepared in three time periods related to the years 1989, 2000 and 2021. Maximum likelihood method was used to classify images from supervised classification. From the error matrix, the Kappa coefficient in this evaluation was equal to 0.83 for 1989, 0.81 for 2000, and 0.92 for 2021. The results show that the forest cover decreases in 2050. In contrast, the area of range land, city, barren land, agriculture and wetland will increase. Based on the goals of the REDD project, the amount of carbon dioxide emissions was calculated until 2050. If the REDD project is not implemented, a large area of forest cover will be destroyed and a lot of carbon dioxide is released. The amount of carbon dioxide in the project area in 2021 is 49,681 tons and will reach 806,732 tons by 2051, and with the implementation of the REDD project in the region, this amount of gas can be increased to the equivalent of 402,321 tons. 404411 tons of carbon dioxide was prevented from entering the upper atmosphere of the earth. Examining changes using satellite images can help managers and planners to make more informed decisions.
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