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Spatial Analysis of the Factors Effective on Flood Occurrence in Ilam City Full text
2021
Tahmasebi, Qobad | Mohammadi, Alireza | Bouchani, Mohammad Hossein
The topic of climate change and the dangers that lie ahead is part of the debate in land management. The dynamics of global change and the sovereign approach of global governments have opened new perspectives on land management issues. One of the hidden challenges in this regard is the increasing risk of the occurrence of floods. The purpose of this study was to undertake metric or measurement model as a spatial basis unit to predict flood occurrence. In the present article, in line with using MikeUrban 2019 software, a wide range of tools and quantitative processing steps were used in accordance with the research objectives. In order to predict floods, the past incident factors were studied, namely a review of the principles and operational indicators related to each parcel using the OLI sensor images of Landsat 8 satellite in the year 2020 through the integrated interpretation method and an examination of the basic map of Ilam city in wet seasons (autumn, winter, and spring). Then, the city coverage map was prepared in two uses, i.e., False Color (Urban) and Land / Water. Next, Google Earth images were used to determine the accuracy and precision of the coverage maps. By combining four selected measures with the highest spatial correlation in 50 random points of the city, hexagonal measures with optimal areas were selected and spatial patterns were analyzed. According to the results, in the actual event (1), eight spatial measures with an area of 68 hectares and coverage of 1.5% of the entire city are at risk of flood. In events 0.8 and 0.9, 19 measures with an area of 170 hectares, 3.6% of the land use coverage of the area, are at potential risk. While there is a high correlation between flood event and type of measure, amount and direction of slope, as well as density and width of road network on one side and drainage network on the other side, in high events (1-8), 28 measures in the residential uses in the detailed design scale with an area of 76.5 hectares, barren and enclosed uses with an area of 70.55 hectares, roads network with an area of 29.75 hectares, and parks and green spaces with 17 hectares were identified as the uses targeted by the flood danger. Among all risky user groups, 29.5% were identified in the newly built group, 44.5% in the maintainable group, and 18% in the decayed urban environment group.
Show more [+] Less [-]Analysis of Spatial Form and Demographic Changes of Shiraz Metropolitan Area During the Period 1996-2016 Full text
2021
Nemati, Zahra | Dadashpoor, Hashem
The number and population of metropolitan areas have increased significantly during the last century, and in line with the increase in population, improved communications, global trends, and other significant factors, there have been many changes in the spatial development of these areas. These changes are observed in metropolitan areas of Iran during the same period, but there have been a few studies on the changes of these areas in Iran. In this study, the urban land density (U.L.D) function was used to investigate the spatial development trend in Shiraz metropolitan area from 1996-2016. The results show that the Shiraz metropolitan area has experienced a decentralized and scattered spatial form from 1996 to 2016. The pattern of changes in the region's spatial development during the years 1996-2006 and 2006-2016 shows that spatial development has become more decentralized and scattered. According to demographic analysis, the highest population density in 2006, 2011, and 2016 can be seen in the central buffer zone of Shiraz metropolis. Based on directional distribution (standard distance), the population distribution has moved to the northwest of the region. In addition, when analyzing the population distribution pattern, the Moran statistics shows that the region population is distributed in clusters. In general, the decentralized and dispersed spatial form and the formation of population clusters in the region's development process show an imbalance in the region's spatial and demographic development. Some of the significant effects of this phenomenon are urban fragmentation, social segregation, car dependency, and the destruction of agricultural lands and gardens.
Show more [+] Less [-]The Management and Planning of Kangavar Geographical Area for Agricultural and Rangeland Uses Full text
2021
Rahmanabadi, Hassan | Hossein Zadeh, Mohammad Mehdi | Mirbagheri, Babak
The assessment of the ecological potential of the environment is to determine and measure the potential power and the natural use type of the land. Therefore, the environment power assessment is a tool for the management of geographical space and strategic planning for sustainable development and correct use of land sources. The aim of this study was to evaluate the ecological potential of agricultural and rangeland use in Kangavar city with an area of 883.9 km2 using Makhdoom ecological model. To this end, the required data and ecological resources were collected and generated. After creating and combining the maps in the ArcGIS system in a multi-hybrid way, the maps of environmental units were constructed and the ecological potential of the area was evaluated using the features of each environmental unit. To do this, the indicators and variables that could be involved in each of these models were examined. To classify the ecological potential of the area for agricultural and rangeland uses and to produce the map of different classes potential, 15 parameters were used as criteria for weighting and measuring the power. The results of Kangavar city ecological potential assessment led to the extraction of 58 environmental units in 7 classes with completely suitable, suitable, weak, and unsuitable power classes for agricultural and rangeland use. An area of about 356.79 Km2 was found to have suitable and completely suitable power for agricultural use. In addition, it was estimated that an area of about 72.23 Km2 would be appropriate for rangeland and rainfed agricultural use with suitable power. An area of about 483.26 Km2 of Kangavar city is currently allocated to agricultural use, while the optimal area for this means is 356.79 Km2. Thus, the land use of an area of about 126.47 Km2 has been converted to agricultural purposes. According to the results, the lands of the region have been exploited more than their potential for agricultural use (irrigated and rainfed) and the lands with rangeland use have been changed to agricultural use.
Show more [+] Less [-]Spatial Modeling and Prioritization of Potential Areas for Determining Location of Hospitals by a GIS-Based Multi-Criteria Decision Making Analyses: A Case Study of the 5th District of Tehran Full text
2021
Zandi, Iman | Pahlavani, Parham
Hospitals are among the most essential human services whose role in the health of the citizens is very important. One of the important issues related to hospitals in developed cities is determining the optimal location for their construction. In this study, in order to select the optimal hospital location, a combination of expert opinions, GIS, and MCDM was used. For this purpose, 12 criteria were selected for the spatial modeling of the potential areas of hospital establishment, and then the weight of each criterion was calculated using the weighting method of Analytic Network Process (ANP). Then, a map of the potential areas for the hospital establishment was prepared and 11 sites in the potential areas were selected. In the next step, the weight of each criterion was determined again using Criteria Importance Through Intercriteria Correlation (CRITIC) method. Then, by the integration of two weighting methods, i.e., ANP and CRITIC, with two MCDM methods, i.e., EDAS and VIKOR, these sites were ranked. The results of spatial modeling showed that the western half of the district is more suitable for the construction of a new hospital than the other areas. According to the results of the ANP, the distance from hospitals, and according to the results of the CRITIC, the seismic vulnerability were the most important criterions in determining the optimal hospital location. Based on the ranking results coming from CRITIC-EDAS, CRITIC-VIKOR, and ANP-EDAS, the site No. 1, and according to the ranking results of the ANP-VIKOR, the site No. 8 have been the most suitable places for the construction of a new hospital. In the light of the results of the site evaluations by experts, CRITIC-EDAS and CRITIC-VIKOR methods are more accurate for hospital location selection.
Show more [+] Less [-]An Analysis of the Role of Local Management in Strengthening the Islamic Republic of Iran, With an Emphasis on the Role of City Councils Full text
2021
Seddiq, Mir Ebrahim | Shirzadi, Reza | Rashedi, Asadollah
Up until now, Islamic Republic of Iran – rising from among people and adopting a religious and divine discourse – has provided a unique model of the administration of people’s affairs in various dimensions through the creation and enhancement of institutions and structures appropriate to its political system. Accordingly, the consideration of ideals in the form of structures, institutions, and approaches is an issue that has a unique role in strengthening the internal structure of this political system. In this article, using the descriptive-analytical method and collecting data through document analysis, library research, and survey methods, city council – as an institution rising from the public vote and a phenomenon similar to local parliament – are defined as the dependent variable. Moreover, in line with the identification of the dimensions and history of these councils, the position of council in Islamic thought is discussed. According to the obtained results, it can be maintained that councils’ importance has four important and effective aspects, namely participation in, distribution of, penetration in, and formation of the identity of power and internal structure strength. To this end, they play roles in four directions, namely strengthening the internal structure cohesion through providing identity to individuals’ roles, enhancing the influence of the Islamic political system in various layers of people and society, fulfilling the maximum participation of people and the role of people in governance, and the just distribution of resources based on reality and the local and national desires. It was found that councils have had greater effectiveness in the fulfillment of maximum participation and involvement of people in governance compared to other directions.
Show more [+] Less [-]The Examination of the Landscape Metrics Changes Using Urban-Rural Gradiant Analysis Method: The Case Study of Tehran Metropolis Full text
2021
Radyn Majd, Golazin | Jozi, Seyed Ali | Hejazi, Rokhshad | Amiri, Mohammad Javad | Ghaffarzadeh, Hamidreza
The detection of urban landscape changes in urban areas is of utmost importance for the maintenance of the safety of environment and the promotion of sustainable development. To this end, the consideration of the spatial metrics capabilities to describe the landscape structure can be a valuable move to identify the growth models in metropolises. The purpose of this study was to provide the urban-rural gradient analysis of the landscape metrics in Tehran metropolis in the year 2018 as well as the analysis of their change trend in order to investigate the spatial-chronological changes in the landscape. In order to analyze the metrics, the moving window method was used at landscape and class levels. To this end, Landsat 8 satellite images were used, and the landcover was divided into human-made, open, vegetation, and water lands in a supervised manner. As with the gradient analysis, transects with 4km*4km dimensions at four directions – namely center-northeast, center-southeast, center-northwest, and center-southwest were directed from District 12 of Tehran Municipality in GIS 10.2 software. The results showed that at the landscape level, the closer we go to the business center of Tehran Metropolis, the number and density of patches increase, while the closer we go to rural areas the average index of landscape shape has relatively uniform changes. At the class level, the more distant we get from the business center of Tehran metropolis, the percentage of human-made patches and open lands increases and that of the vegetation patches decreases. Then, it might be concluded that urban development has brought about an increase in the density of patches in landscape, such that in the central transect, the continuity of landscape is reduced, and the fragmentation of the structural elements of landscape is increased. The land use changes have led to the expansion of the city toward the country and have negatively affected the vegetation and water resources.
Show more [+] Less [-]The Spatial Analysis and Ranking of the 15 Districts of Isfahan City Based on Public Transportation Access Justice Full text
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.
Show more [+] Less [-]Drought Forecasting for Future Periods Using LARS-WG Model: The Case Study of Kermanshah City Full text
2021
Heshmati, Sara | Ramezani Etedali, Hadi
The prediction of climactic changes is of great importance due to their destructive effects on aquatic, environmental, economic, and social resources. Accordingly, the purpose of this study was to predict the climactic changes of Kermanshah city using micro-scale general atmospheric circulation models accessible in LARS-WG6 (GFDL-CM3, MPI-ESM-MR, MIROC5) model in scenarios RCP4.5 and RCP8.5 for the 2020 to 2100 period based on the benchmark period of 1980-2010. In order to evaluate the data forecasted in LARS-WG model, the error rate of the observed and predicted data was addressed using R2, RMSE, MSE, and MAD criteria. The results showed that LARS-WG model had the needed capability to predict climactic data in future. In the secondary models, the MPI-ESM-MR model in scenario RCP4.5 showed a higher reliability rate compared to other secondary models evaluated in the study. Moreover, all models indicated increases in the average minimum and maximum temperature and forecasted changes in rainfall pattern in future periods in the studied area. Then, the SPI and De Martonne indices were calculated for all models. According to SPI index, all evaluated climactic models demonstrated that by the year 2100, the years with normal index would decrease while the years with dry conditions would increase. Moreover, based on De Martonne index, the GFDL model in RCP8.5 scenario estimated the climactic changes level more than other models, and predicted that dry and semi-dry years will be more than wet years. Contrarily, the MIRO model in RCP45 scenario acted more optimistically and predicted less climactic changes.
Show more [+] Less [-]An Analysis of the Reasons for the Decline of the Position of Tabriz Metropolis in the Urban System of Iran and the Prediction of its Population and Position by 2031 Full text
2021
Ghorbani, Rasoul | Alizadeh, Hooshmand | Karami, Sonya
Demographic changes in recent decades have led to rapid changes in Iran's urban system and its hierarchy, with one of its consequences being the increase or decrease in the ranking of cities in this system. The present study examines the position of Tabriz metropolis in the urban system of Iran from 1335 to 1395, and by forecasting the population of this metropolis by 2031, it tries to determine the future position of this city in the urban system of Iran. This study is practical in terms of purpose and descriptive-analytical in terms of nature and research method. The data in the present study were obtained through document analysis and field study (questionnaire and interview). Interviews were used to understand the causes of emigration and a questionnaire was used to understand the causes of fertility decline in Tabriz metropolis. The sample sizes for both instruments were determined based on the saturation principle. The exponential model, Spectrum software, and rank mobility index were used to predict the demographic factors, population forecast, and the study of metropolitan rank changes in the urban system, respectively. The obtained results showed that the decrease in fertility rate and migration are the main reasons for the sharp decline in population growth in the metropolis of Tabriz, with the economic reasons being the main reason. In addition, assuming the fertility rates of 1.5, 1.8, and 2.1 in Tabriz, we will see 1.64, 1.69, and 1.74 million increases in the population of the city, respectively, as well as a decrease in the population of minors and a doubling of elderly population over 65 by the year 2031. The results of population forecast show that the position of Tabriz metropolis will be stabilized as the sixth largest city of Iran's urban system by 2031, but its distance from the seventh metropolis (Qom) will be less, which requires special attention and proper management to prevent its rank from falling again.
Show more [+] Less [-]Modeling the Process of Spatio-Temporal Changes in Land-Use and Urban Development of Ahvaz Based on Spatial Planning Approach Full text
2021
Abiyat, Mohammad | Abiyat, Mostefa | Abiyat, Morteza
The land-use changes and urban development are among the fundamental topics of spatial planning. Monitoring changes in previous years and predicting these changes in the coming years have a significant role in planning and organizing urban spaces. The purpose of this study was to investigate land-use change and urban development in Ahvaz with a landscaping approach based on balanced urban development. .Images of TM (1989), ETM+ (2002), and OLI (2019) of the Landsat satellite are the basis for analyzing this trend. LCM model was used to identify the past changes, while CA-Markov chain model was applied to predict the future changes. These images were classified using a support vector machine algorithm of the object-oriented method, and the land-use maps were prepared using three sensors with four classes of vegetation, barren areas, constructed areas, and water zones. The accuracy of maps was improved separately using NDVI and SAVI indexes in the classification of the images. The efficiency of the indexes was measure by kappa coefficients and the overall accuracy of land-use maps, and then changes were investigated using maps related to the superior index. The results showed that maps related to the SAVI index were more accurate and accordingly, they were used in assessing land-use changes. The LCM model showed that in the periods 1989-2002 and 2002-2019, 2602.92 hectares and 31174.77 hectares were added to the built areas, respectively. In both periods, the most changes were about converting barren lands to built-up areas and the least changes were related to the transformation of the built-up areas to water areas. The results of the CA-Markov model until 2029 showed the continuity of the increasing trend of built-up areas, such that in ten years, 2238.82 hectares will be added to the built-up areas, and it is anticipated that the area will reach approximately 12345.63 hectares by 2029.
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