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The Quantification of Landscape Metrics in the Protected Areas: The Case Study of Sorkhabad Protected Area, Zanjan Province, Iran Texte intégral
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.
Afficher plus [+] Moins [-]Assessment of Ecological Capacity of Kangavar County Geographical Space Based on Natural Environment Properties Texte intégral
2020
Rahmanabadi, Hassan | Hossein Zadeh, Mohammad Mehdi | Mirbagheri, Babak
The assessment of the ecological potential of the environment is to determine or predict the potential power and natural land use type. Environmental assessment is therefore a tool for strategic land use planning. The aim of this study was to evaluate the ecological potential of urban, rural and industrial land use in Kangavar city with an area of 883.9 km2 using Makhdoom ecological model. In the process of research, the required data were collected, produced and produced. After creating and combining the maps in the GIS software 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 indices and variables that could be involved in each of these models were examined. To classify the ecological potential of the area for urban, rural and industrial uses and to map the power of different classes, 18 parameters were used as criteria for weighting and power determination. The results of Kangavar city's ecological assessment indicate that a 100.26 square kilometer area (11.34%) of Kangavar city is suitable for urban, rural and industrial use for 1st class. Also in the city, 483.1 square kilometers (54.64%) is quite suitable for 2nd floor. By comparing the existing and optimal land use map, it was determined that the area of urban land use development in inappropriate zones is 2.5 square kilometers.
Afficher plus [+] Moins [-]Modeling of Ecosystem Services based on Land Cover Change and Land Use Using InVEST Software in Jahannama Conservation Area (Case: Carbon Sequestration Ecosystem Service) Texte intégral
2020
Fadaei, Ensiyeh | Mirsanjari, Mir Mehrdad | Amiri, Mohammad Javad
Several benefits that humans get from ecosystems are called ecosystem services. Carbon sequestration as an eco- regulation service is declining, due to the transformation and destruction of the earth used to recompense the burgeoning human needs for development. In the present study, a pilot landscape of hyrcanian forests, protected area in Jahannama was selected. By examining the land use / cover changes during 2001 to 2018, future condition of the land will be set to determine the carbon storage and carbon sequestration model in 2036. The amount of carbon in the four carbon storage sources including biomass, underground biomass, soil and organic matter along with IPCC reports facilities, field studies and sampling was extracted. Deterioration trend in forest lands and grassland with remarkable role in carbon sequestration was sharpened. The reduction trend will be predicted to reach as much as 40 per cent which will be equivalent to 400859 tons per land. With the same rate in land deterioration, a considerable decrease in ecosystem storage and carbon sequestration’ potentiality will be expected present study indicated that the integration of the concept of the ecosystem services in land planning discourse and land use management via the provision of spatial maps of ecosystem services on a regional scale, along with the rational development of human use, ecological hazards should be minimized, as a result better decision will be made in planning the land. It is also suggested that to enhance the quality of Jahannama ecosystem services in development plans and review within the protected boundaries and the principled management of land use within the protective boundaries.
Afficher plus [+] Moins [-]The Spatial Correlation Analysis of Population Changes With the Intensity of Tehran’s Environmental Vulnerability Changes in the Last Decade Texte intégral
2020
Rezaei Rad, Hadi | Akbarian, Zahra
Compared to other cities, metropolises are exposed to the more vulnerabilities derived from environmental disasters because of their population, and the vulnerability of most of them is even increasing. The assessment of vulnerability, especially in specific intervals, generates new foundations for better urban planning and management. Additionally, the concept of the term “vulnerability” has been emphasized in the context of studying the relationship between natural-human interconnected systems, and consequently, in urban ecology. On the other side, population movements in different districts of big cities always follow different models. Therefore, the main purpose of this research is to identify the spatial connection of population changes of the districts of Tehran metropolis with the changes in environmental vulnerability intensity in the last decade. The methodology of the research included the assessment of vulnerability in three layers, namely the damages stemming from natural disasters, urban structure, and environment in the last decade in Tehran. In addition, the vulnerability has been measured in accordance with the census statistics of population changes in 22 districts of Tehran in the recent decade. The results of the research modeling show that the southern area of the city has had the highest increase in vulnerability during the last decade, and so, it has had the highest reduction of the population, too. Nonetheless, the district 18, which is located in the west zone of the city, has faced an increase in population despite its increased vulnerability. Moreover, the northeastern area of the city has faced increased vulnerability as well as a sharp increase in population during the last decade. These changes can challenge this part of the city because of possible future crises. Finally, the reduction of vulnerability along with the increase in urban population has happened in the northwestern area. To keep this vulnerability low, the acceptable capacity of the population in this part of the city (especially district 22) should be taken into account.
Afficher plus [+] Moins [-]Assessing the Agricultural Land Use Potential in National Lands Using Spatial Planning Approach: The Case Study of Chalancholan Basin, East of Lorestan Province Texte intégral
2020
Sharafi, Siyamack | Noorollahi, Darioush
Due to the growing importance of environmental problems and increasing human interventions in natural environments, it is necessary to use spatial planning and sustainable development approach in order to conserve natural resources and move along with the land and its productive capacity. The rough topography of Lorestan Province has caused a large part of its lands to be recognized as national lands due to their steep slope and the necessity of preventing the destruction of natural resources. However, there some activities such as agriculture, industry, tourism, etc., which are possible if certain conditions and criteria are met. Regarding the dependence of the region's economy on agriculture and the increase in unemployment, these lands can be used to develop agricultural activities based on their environmental potentials using spatial planning approach. The purpose of this applied study was to determine the potential of national lands of Chalancholan basin in the east of Lorestan Province for the development of agricultural activities. We used tools and data such as topographic maps, geological maps, climate data, pedology, hydrology, and Arc GIS software to determine national lands with agricultural potential based on the guidelines and standards of the Forests, Range, and Watershed Management Organization of Iran, taking into account the local conditions. To this end, first, the land units (geomorphology) were determined and then, the allowable land uses were specified in each of the homogeneous environmental unit. Next, different variables were used to assess the suitability of national lands for agricultural land uses. The study results showed that national lands under study are more suitable for dryland agriculture compared to irrigated agriculture and horticulture, the reason of which is poor pedogenesis due to geological characteristics of the region and limited water resources. The study results indicate that the lands located in the plains and alluvial sediments are more suitable for irrigated agriculture and horticulture, while the lands surrounding the plains are more suitable for drayland agriculture.
Afficher plus [+] Moins [-]The Typology of the Spatial Pattern and the Suggestion the Possible Future Scenarios of Possible Urban Systems for the Development of Future Urban System of Alborz Province Texte intégral
2020
Sharifzadegan, M. Hossein | Khalili, Bita
Population distribution, economic functions, as well as the status and role of cities in the urban system change and evolve through their interaction with other cities over time. This change in the organization of the urban system is not a static one, but rather it is a context-dependent issue. Alborz province has experienced highly rapid changes in the urban system that have led to the emergence of severe imbalances in the urban system, increasing population and functional concentration in its metropolitan area compared to other cities and the marginalization of other cities of the province in the urban system. The typology of urban system in Alborz province that aims at describing the spatial pattern in which the cities of this urban system are organized and proposing the possible scenarios for the future spatial pattern of this urban system are the subjects of this article. This issue has been pursued through the analysis of the morphological and functional spatial pattern of cities, the analysis of the grounds affecting the formation of the urban system, and for the examination of the possible futures for the urban system. This research had mainly a descriptive nature, relied on quantitative methods and spatial analyses, and emphasized both morphological and functional aspects. According to the findings, the main east-west corridor of the province is the most important factors in the spatial pattern of this province’s urban system. The urban system of the province might develop in future through three possible spatial scenarios. These scenarios include the corridor, polycentric, and monocentric development patterns. It seems that in the urban system of Alborz province despite the spatial concentration of the population and the majority of the provincial functions in Karaj metropolis, there are potentials for the realization of a more balanced development. The potential and tendency to the corridor development model around the east-west axis, which agrees with the natural, infrastructural, and economic structure of the region, is one of these tendencies that can create a demographic and functional balance in the urban system of the province and lead its cities to take various economic roles.
Afficher plus [+] Moins [-]An Evaluation of the Interaction of Higher Education and Industry Functions From the Spatial Planning Perspective Texte intégral
2020
Ghorbani, Ramin | Ziari, Keramatolah | Sejoudi, Maryam | Farhadi, Ebrahim | Abullah Hussein, Shakhawan
One of the important aspects of development from the spatial perspective is the evaluation of the effective long-term processes on the institutional mechanisms of a land and the determination of share of the respective areas in this regard. For many years, economy has been hurriedly moving toward a knowledge-based stance, and the countries that have neglected this movement have been deprived of fundamental developments. In this applied study, which adopts an analytical approach and a quantitative view, the necessity of the proposition of a strategic attitude to the two-way relationship between higher education and the industry sector of Iran is addressed. To this end, first an overview of the previous studies and theoretical principles are made. Then, following the questions and hypotheses and determining the evaluation and analysis methods, the detailed information on over 11 variables (including panel data of 31 provinces of Iran from 2016 to 2019) are collected. These are then analyzed and tested using Excel, Eviews, and Arc GIS through spatial econometrics, generalized method of moments (GMM), weight matrix and geographic-spatial correlation (λ), and KP-HET diagnostic tests. According to the results, the spatial correlation between higher education and industry in Iran is highly significant, and the shock resulting from the industrial and educational development is completely mutual. That is to say, the shock inflicted upon a given province has spread to other provinces of Iran. The findings of this study confirm the effects of the emphasis on the centralization policy stereotype and the prescriptive – rather than land-use-based – roles given to certain parts of Iran. In fact, the very high spatial correlation demonstrates that the nine less-developed provinces of Iran have experienced trivial industrial growth due to a lack of higher education infrastructure. On the other hand, the results of this study shows how the market demand for labor of the university graduates is aligned with the functions of the knowledge-based industries of Iran.
Afficher plus [+] Moins [-]Evaluating the Potential of Landslide Susceptible Areas Using FBWM Model: A Case Study of Tabriz City Texte intégral
2020
Moharrami, Meisam | Argany, Meysam
Environmental hazards, which encompass a wide range of natural hazards and human hazards, are among the barriers to development in different areas. Landslide is one of the hazards affecting different natural and anthropogenic factors and is one of the barriers to socio-economic and constructive development in each region. In this study, considering the different criteria, the potential of landslide occurrence in Tabriz city has been evaluated using FBWM model. The criteria used in this study are slope, curvature, elevation, fault, geology, vegetation, river and creek, roads, aspect, and land use. FBWM model is used to weight the criteria. This model is one of the newest multi-criteria decision-making models that weigh the criteria by comparing the criteria with each other and generating a nonlinear optimization problem. Finally, after weighting the criteria and creating standard maps, the standard maps and weightings were merged together and overlaid to produce the final map of landslide susceptible areas in Tabriz City. Based on the results, the north and northeast areas of Tabriz have high potential for landslides; these areas correspond to Valiasr town, Baghmishah, Einali Mountains, Pasdaran highway and the surrounding areas. On the other hand, the southern regions of Tabriz have a low potential for landslides. According to the results, 2.5% of Tabriz territory is located in very low potential areas for landslide occurrence, 15.16% is located in low potential areas, 36.04% is located in moderate potential areas, 40.97% is located in high potential areas, and 5.33% is located in very high potential areas for landslide occurrence. The results of this study have implications for organizations and organs such as Tabriz Municipality, Ministry of Roads and Urban Development, the Geological Survey and Mineral Explorations of Iran (GSI), and other organizations related to environmental risks.
Afficher plus [+] Moins [-]Assessing the Relationship between the Spatial Concentration, Specialization, and Diversity of Industries, and Competition between Industries (Case study: Counties of Iran from 1996 to 2011) Texte intégral
2019
Sasani, Mina | Dadashpoor, Hashem
Distribution of production activities and establishment of industrial units in different regions depend on the decision of firms regarding their location, but there are many important factors that affect the decision-making process. This research main goal is to understand the relationship between industry specialization, diversity of industries, competition between industries, and the concentration of industries over time. The research method is quantitative and follows the method employed by Glaeser et al. (1992). The effect of specialization, relative diversity of industries and competition between industries on industrial concentration have been investigated using geographically weighted regression method. The result of this assessment shows that during the study period with the increasing specialization of industries in the county, in most industrial sectors, increasing industry concentration has occurred. But between the relative diversity of industries and industrial competitiveness and the geographic concentration of industries no significant relationship in the counties was observed.
Afficher plus [+] Moins [-]The Role of Small Cities in Bringing Balance to Regional Sustainable Development and Changes in the Urban System (Case Study: Alborz Province from 1986 to 2016) Texte intégral
2019
Sharif Kazemi, Zeynab | Mousavi, Mir Najaf
One of the important strategies that have been taken into consideration in the last half-century to counter regional imbalances, caused by the increasing growth of large cities, is the creation of small cities. Due to the availability of some facilities and services, small cities are considered as one of the important centers for bringing balance to regional development. The method of the present research is a descriptive-analytical one, and the purpose of this research is to study the status of changes in the urban system of the small cities of Alborz province in order to bring balance to the regional sustainable development. In order to find out the status of small cities in the urban system in a 30-year period (1986-2016), rank-size models, as well as entropy and balance sheets models were used, and then their role in bringing balance to the regional development was evaluated. The results of the study show that the Entropy coefficient without counting the small towns, will still have imbalances. The rank-size logarithmic model, by counting small cities with the slope of the line amounting to -1.94 and without counting small cities reduced to -1.21, indicating the undeniable role of small cities in the urban system. Also, the results of the balance sheet model show that component changes are mainly intra-class and are due to the growth of cities. Moreover, concerning the process of changing villages to cities, changes resulted from the formation of new cities can be seen only in 2006.
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