خيارات البحث
النتائج 21 - 24 من 24
An Analysis of the Effects of the Change in Climate and Surface Soil Conditions on the Frequency of Dust Storms: The Case Study of Khorasan Razavi Province
2021
Naeimi, Maryam | Khosroshahi, Mohammad | Mir Akbari, Maryam | Gohardoost, Azadeh | Zandifar, Samira | Ensafi Moghadam, Tahereh
In recent decades, dust storms have intensified due to climate changes, including drought and human interventions. In addition to removing soil particles, dust brings storms bring about severe economic, social, and health problems. Due to its strategic conditions – including its status as an industrial and agricultural hub and the province hosting more than 29 million Iranian and international pilgrims, especially during the seasons and months with specific holidays – should be prioritized in the examination of dust storm frequency. The purpose of this study was to examine and track the frequency of dust storms and analyze the effect of climactic changes on them through the investigation of drought trend as well as the trend of changes in the land surface coverage percentage during the statistical analysis period. The results of counting the dust codes showed that dust storms with local origin had the highest frequency. According to the monthly analysis, Sarakhs and Mashhad stations had the most dust phenomena, with the most dusty days in the study area during summer and spring seasons, especially June and July months. The results of regression analysis of drought index and the monthly local dusty days indicated the existence of a significant, positive relationship between dust increase and drought intensity in Mashhad and Sarakhs stations during the statistical period of 27 years at 99 percent confidence interval. Finally, in the light of the results obtained from the examination of the land surface changes, it is recommended that land use plans be used along with short-term methods of soil stabilization in order to reduce the economic damages and preserve people’s health against dust during busy months and seasons so as to achieve the goals of long-term methods.
اظهر المزيد [+] اقل [-]An Analysis of the Interactions of the Spatial Structures of Social Harms in Tehran
2021
Azimi, Azadeh
Various spatial instances and outcomes can be shown for every social phenomenon in the urban arena, and this indicates the spatial behavior of social phenomena. The examination of suchlike phenomena from the viewpoint of correlation and synergy reveals the existence of an interactional pattern among them. In this article, it is tried to provide a brief description of the spatial distribution of variables related to social harms such as joblessness, addiction, etc., in the form of spatial statistical analysis. The research method is descriptive-analytical, and it can be categorized as an applied study. In terms of data collection method, the study adopted library research. In order to analyze the data, we used spatial statistics tests in ARC GIS. In the light of the spatial structure of the social class and the spatial pattern of the variance of the rich and poor areas of Tehran, it was found that poverty and dispersion are among the main stimuli of the concentration of various social harms in poor neighborhoods.
اظهر المزيد [+] اقل [-]The Quantification of Landscape Metrics in the Protected Areas: The Case Study of Sorkhabad Protected Area, Zanjan Province, Iran
2021
Hosseini, Seyedeh Fariba
One of the environmental hazards and ecological crises that our world is facing now is the phenomenon of land use change. The timely and accurate detection of these changes and land features has an essential role in better understanding the relationships and interactions between human and natural phenomena in order to better manage and use natural resources using theoretical-analytical method. The present study examined and analyzed metrics related to a period of over 30 years. Sorkhabad Protected Area was selected as the target area. The TM-ETM_OLI image series of Landsat satellite in two periods were exploited to investigate the trend of changes using Envi software and the maximum probability classification method with 86% accuracy of information. Then, the available metrics in Fragstate software were used to process the data at three levels, namely patch, class, and landscape. Along with analyzing and evaluating these three levels, the changes in vegetation and animal distribution changes map – prepared by the Zanjan Environmental Research Center foresters in order to map the distribution of native animals of the province – was also examined. The results showed that the conversion of pasturelands into agricultural lands has caused the loss of soil and vegetation and has negatively affected the habitat and population of caracal and deer species that are dependent on these environments. Moreover, overgrazing and deforestation have reduced the growth of forestlands; this has led to the destruction of the habitat of leopard and brown bear, and these changes have also contributed to habitat destruction.
اظهر المزيد [+] اقل [-]The Spatial Analysis and Ranking of the 15 Districts of Isfahan City Based on Public Transportation Access Justice
2021
AbedKuran, Sahar | Nooraie, Homayoon
In the current era, justice and advancement are deemed as the two wings of sustainable development, with each being worthless without the other. As one of the main service systems in cities, public transportation has an important role in the realization of justice. As a result, the purpose of this article was to analyze and rank the 15 districts of Isfahan metropolis based on justice in accessing public transportation. In order to attain this goal, the required data was collected using document analysis and field study (through observation and questionnaire). The Best-Worst (BWM) and COCOSO methods were used to analyze the data. The results indicated that Districts 1 and 3 had the most and Districts 9, 11, and 14 the least public transportation facilities. Moreover, the need to public transportation – in terms of the number of users – was highest in Districts 8 and 10 and lowest in Districts 2, 9, and 11. The combination of these two factors also showed that Districts 1, 2, 3, and 15 had bigger facility to user ratios, while Districts 8, 10, 11, and 14 had smaller facility to user ratios. In the other districts, the facility to user ratio was mainly moderate. Therefore, it is necessary to pay more attention to this gap between facilities and users’ needs when planning for public transportation in future.
اظهر المزيد [+] اقل [-]