Showing 229 results for Ca
Ghazal Asadi Eskandar, Bahador Zamani, Shahab Kariminia, Maryam Ghasemi Sichani,
Volume 25, Issue 79 (1-2026)
Abstract
Increased temperatures in urban areas due to high energy consumption and greenhouse gas emissions are some of the problems of today's cities. Urban open spaces in hot and arid climates experience this problem more in summer. The purpose of this study is to show the relationship between morphological components of the urban fabric and thermal comfort through integrated analysis. In this study, urban fabric types were extracted by considering ground space index, floor space index, open space ratio, average height, streets orientation, streets organization, and type of plots according to their configuration of mass and space. To study thermal comfort, a field study was carried out in five neighborhoods in the historical context, for five continuous days in summer. Environmental variables including air temperature, humidity, radiant temperature, and wind speed were measured, and the physiological equivalent temperature index was calculated using ENVI-met software; thermal comfort in the neighborhoods with different morphological characteristics was analyzed. The results showed that more than half of the data during the day in the hot season in all five neighborhoods are in conditions of extreme heat stress. Comparison of neighborhoods with different morphological features indicated that two neighborhoods with higher open space ratios, despite the difference in the orientation of the streets and the type of plots, have lower thermal comfort compared to other types. A neighborhood with a higher ground space index and a lower open space ratio has a lower average physiological equivalent temperature.
Salman Kazemian Souraki , Fereshteh Nasrollahi, Amin Deilami Moazzi,
Volume 25, Issue 79 (1-2026)
Abstract
Shia political Islam, centered around Iran, is a complex and dynamic phenomenon that has undergone numerous transformations in recent decades. Understanding the future trends of this intellectual and political movement is of great importance to analysts, politicians, and the general public. This article employs a futures studies approach to examine the trends of Shia political Islam within Iran's political geography. This foresight approach allows us to look beyond the current situation and outline various scenarios for the future of politics and society in Iran. The methodology of this research is descriptive-analytical, utilizing library and documentary sources, including qualitative and quantitative analysis of historical data, expert interviews, and content analysis of media and religious texts. The research findings indicate that Shia political Islam in Iran's geography is undergoing a period of transformation, influenced by various factors such as demographic changes, social and economic developments, and geopolitical shifts. Several potential scenarios for the future of Shia political Islam in Iran's political geography are presented, including: the Continuity Scenario, the Reform Scenario, the Radicalism Scenario, and the Secularism Scenario. Considering these scenarios, the analysis of probable trends and events in the scenarios, and political and security developments with a view to challenges and opportunities in the Middle East region, the Islamic Republic of Iran, adhering to the Continuity Scenario along with the Reform Scenario, aims to strengthen republicanism (religious democracy) while emphasizing the preservation of independence and indigenous Islamic identity in the region, and to have a more prominent presence in the Middle East.
Mr Framarz Nik, Phd Ata Aleh Abdi, Phd Hosein Rabiei, Phd Hasan Rabei,
Volume 25, Issue 79 (1-2026)
Abstract
This study aims to identify the determinants influencing the political spatial organization of Alborz province. Employing a descriptive-analytical approach, this research utilizes qualitative data derived from library investigations and field studies. The methodology encompasses authentic document analysis and expert interviews to identify and examine factors affecting political spatial organization in Alborz province through grand theory application. Analysis revealed that determinants influencing political spatial organization in Alborz province encompass 50 contextual factors, 22 causal factors, 55 strategic factors, and 56 consequences. Predominant contextual factors include justice, social equity assurance, citizenship rights, national spatial political management, appointment of political administrators in divisional units, government-public communication, responsibility emphasis, and accurate recognition. Societal culture and geographic positioning represent primary causal factors, while strategic insight and educational-research strategy formulation constitute essential strategies. Administrative, military-security, and economic factors emerge as consequential elements impacting political spatial organization in Alborz province. The provincial state system operates as an open system, wherein constituent elements exhibit synergistic relationships and demonstrate temporal enhancement potential. Researchers synthesized findings into a comprehensive model demonstrating that optimal factor utilization within the system facilitates success, whereas inadequate implementation results in systemic failure within Alborz province's state management framework.
Dr Saeedeh Fakhari,
Volume 25, Issue 79 (1-2026)
Abstract
Investigating the awareness of the local community towards the development of ecotourism is very important and necessary for future planning. Ecotourism in any region affects the lifestyle of local people and their economic-cultural conditions. On the other hand, ecotourists are also influenced by the culture of the host society and its values. Therefore, this study examines the local community's awareness of supporting ecotourism development in Damavand City. Due to the preservation of unique biological diversity, climatic conditions, and the frequent visits of tourists and ecotourists to this region, the local community needs to know about ecotourism, which made this research necessary. The target community of this study is the local community of residents of Damavand city. Therefore, using Cochran's formula, the sample size was estimated to be 384 people. The data was collected through a researcher-made questionnaire, which was used to determine its validity, in addition to seeking opinions from experts (face validity), convergent validity was used. To calculate its reliability, Cronbach's alpha method and composite reliability were used. The results of the inferential statistics that were conducted using confirmatory factor analysis (Smart PLS software) showed that the four components of the research (local community awareness, economic poverty, cultural poverty, and ecotourism development) have homogeneity and reliability, and the awareness of the local community It has a significant relationship on the development of ecotourism with the mediating role of cultural poverty with the test statistic value of 4.195 and economic poverty with the test statistic value of 5.397. The results showed that the awareness of the local community on the development of ecotourism with the test statistic value of 2.032 indicates the low level of awareness of the local community towards the development of ecotourism.
Arefe Shabani Eraghi, Seyed Mohammad Zamanzade, Fariba Karami,
Volume 25, Issue 79 (1-2026)
Abstract
Reconstructing paleoclimate, particularly environmental temperature, plays a crucial role in understanding both current and future climate patterns. The aim of this research is to investigate the climatic conditions and estimate the ambient temperature during the Holocene period based on two sediment cores extracted from the Jazmurian Basin. Paleotemperature reconstruction was conducted using several methods, including the calculation of the standardized coefficient of variation of oxygen-18 and carbon-13 isotopes. For this purpose, the isotopic analysis of oxygen-18/oxygen-16 and carbon-13 was performed. In Jazmurian core 1, the initial temperature was estimated at 46°C. A decreasing trend of approximately 10°C was observed down to a depth of 175 cm, distributed across eight stratigraphic levels. At 175 cm, the temperature shows an increasing trend, followed by a decline at the subsequent level, and then a return to an increasing and stable trend in the next two levels. In Jazmurian core 2, the initial temperature was approximately 50°C. A sharp decrease in temperature is observed between depths of 80 to 125 cm. Subsequently, there is a slight increase of about 1°C, which remains relatively stable until a depth of 170 cm. Beyond this point, the temperature decreases again in the final two layers. The concentration of carbon-13 in core 1 ranges from 0 to 25.6, while in core 2 it varies between 25.9 and 27.1. In core 1, six carbon -13 isotope samples show a value of zero, indicating an absence of carbon-13 in those sediment layers. In contrast, core 2 displays a narrower range of variation in carbon-13 values. The isotopic and temperature variations observed in these sediment cores reflect different climatic phases during the Holocene in the Jazmurian region. Such climatic changes are often linked to cultural shifts, and the decline of ancient civilizations has frequently coincided with environmental transformations. The findings of this research may be of significant value to archaeology researchers, particularly those studying ancient Iranian civilizations.
Farzad Shirzad, Mr Bohlol Alijani, Mehry Akbary, Mohammad Saligheh,
Volume 26, Issue 80 (4-2026)
Abstract
Climate change and global warming are very important issues of the present century. Climate change process, especially temperature and precipitation changes, the most important issue is environmental science. Climate change means a change in the long-term average. Iran is located in the subtropical high pressure zone in arid and semi-arid regions and the Hyrcanian forest is a green area between the Caspian Sea and the Alborz mountain range. At the 43rd UNESCO Summit, the Hyrcanian forests were registered as the second natural heritage of Iran. Beech is one of the most important tree species and the most industrial species of Hyrcanian forests It accounts for about 18 percent of the northern forest volume (from Astara to Gorgan with a life span of about 250 years). The study area is located in the Shanderman basin in western Guilan province. In this research using tree dendroclimatology, Use of vegetative width of beech tree rings, Weather station statistics located in the study area, And Mann-Kendall nonparametric statistical method, To Investigate Climate Change Trend on Growth Time Series and Pearson Statistical Method, in order to evaluate the correlation of diameter growth of beech tree rings with climate variables in the region, an attempt was made. Results of time series of beech tree growth rings over 202 years. Using the nonparametric method Mann- Kendall showed, Changes in growth rings of beech trees have a downward and negative trend, at level 5 %, it was significant. Temperature Minimum, Average, Maximum, and Evaporation during the growing season, there was an upward trend and Annual precipitation there was a downward trend. Using the Pearson method Fit correlation of growth ring diameter with temperature, For the average monthly in February and the average minimum temperature in July, August and September and Negative correlation, for average maximum temperature in February, July, August and September at 95% level, it was significant and precipitation in June, the correlation was 95% positive and significant.
Dr. Vahab Amiri, Dr. Nassim Sohrabi, Dr. Seyed Mohammadali Moosavizadeh,
Volume 26, Issue 80 (4-2026)
Abstract
This study investigates the impact of natural and anthropogenic factors on the physicochemical composition of groundwater in the Qazvin aquifer. Based on the optimized Gibbs diagram, the concentration of samples at the end of the freshwater interaction path with silicate units results from geochemical evolution due to the dissolution of these geological units and an increase in the Na/(Na+Ca) ratio. The ion exchange mechanism was assessed using bivariate diagrams of Ca+Mg vs. SO4+HCO3 and Schoeller's chloro-alkaline indices CAI-1 and CAI-2. The results indicate that in 68% of the samples, direct ion exchange, and in 32%, reverse ion exchange control the groundwater chemistry. The changes in Ca vs. SO4 indicate that gypsum dissolution alone is not the source of these ions. These changes could be due to ion mobility and transport during pedogenic processes (sulfur biogeochemical cycle) and anthropogenic factors. The study also examined the role of factors such as agricultural input, atmospheric input, soil nitrogen, sewage input, manure input, chemical fertilizers, and the denitrification process in groundwater pollution using NO3/Na vs. Cl/Na and the NO3/Cl vs. Cl diagrams. The results reveal that agricultural and sewage inputs significantly impact the NO3 and Cl content. Furthermore, in some locations, especially in the southeast of the aquifer, the denitrification process causes a decrease in NO3 concentration. These findings can contribute to effective water resource management in this strategic aquifer by understanding the controlling mechanisms of physicochemical composition and identifying potential groundwater pollution sources.
Zahra Hedjazizadeh, Al Karbalaee, Mokhtar Fatahian,
Volume 26, Issue 80 (4-2026)
Abstract
This study investigates the spatial dynamics of the subtropical anticyclone over Iran during boreal summer, using daily ERA5 reanalysis data (1980–2020) and the Getis-Ord Gi* statistic to identify statistically significant hotspots (p < 0.01) in 500-hPa geopotential height (Z500) anomalies for June–August. Results reveal that the peak statistical hotspot occurs in July: a prominent warm cluster with Z-scores up to +4.1 (99% confidence level) forms over southwestern Iran (27°–32°N, 48°–60°E), reflecting the strongest positive departure from the long-term Z500 climatology. Conversely, a cold cluster with Z-scores reaching −10.2 emerges over the northwest (West Azerbaijan and Kurdistan provinces) the lowest value recorded over the entire period indicating pronounced geopotential depression driven by the orographic influence of the Alborz–Zagros ranges and incursions of mid-latitude systems. Histogram analysis of Z-scores confirms a distinctly bimodal distribution in July, with high frequencies in the [+2.5, +4.1] and [−10.2, −2.5] ranges and a pronounced trough near Z ≈ 0, underscoring strong spatial segregation between warm and cold clusters. Notably, the eastern half of Iran (central and eastern regions) consistently lacks significant hotspots across all three months, suggesting the presence of a dynamic transition zone shaped by the competition between subtropical and mid-latitude circulations. In August, although absolute Z500 exceeds 5890 m, the Z-score diminishes (+4.0), indicating that cumulative surface heating elevates the mean geopotential height but its anomalous intensity relative to climatology weakens compared to July. Collectively, these findings suggest that the dynamical peak of the Iranian subtropical high lags the peak of surface heating by approximately one month.
Professor Keramat Ollah Ziari, Mr Amin Mahmoudiazar, Mr Khalil Jangjoo, Leila Aslani,
Volume 26, Issue 81 (6-2026)
Abstract
One of the issues raised in the developing countries of the world is the issue of reducing damages caused by natural and man-made hazards. Various theories and paradigms such as crisis management and resilience have been proposed to reduce the level of risk vulnerability. Among the mentioned vulnerabilities is physical vulnerability. Now, the most important question that is raised in this research is whether according to the various studies that have been done in the field of physical vulnerability, apart from objective measures, the level of satisfaction of the residents has also been examined and whether it exists. Is there a relationship between objective and subjective indicators in this field? The case study studied in this research is Region 4 of Urmia City, which has a problematic context. This research is of an applied type and its method is descriptive-analytical, to examine this objective and subjective relationship of physical vulnerability, first objective variables were examined using spatial analysis and then subjective variables were examined using a Likert scale. questionnaire. And finally, this relationship has been measured using Pearson's correlation coefficient. The research results indicate that according to the correlation coefficient of 0.623 between subjective and objective variables; There is a significant relationship between the objective view (reality on the ground) and the subjective view (satisfaction of residents) in the field of urban physical vulnerability indicators.
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