Urban Planning
ebrahim zahedikelaki; Sadra Motevalli; hassan mahmoudzadeh; Gholamreza Ganbaz ghobadi
Abstract
Introduction
The trend of urban change and subsequent changes in the ecological structure of Behshahr city during the last 34 years has caused many environmental problems. So that the horizontal expansion of the city to the four directions and consequently the increase of ecological footprint ...
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Introduction
The trend of urban change and subsequent changes in the ecological structure of Behshahr city during the last 34 years has caused many environmental problems. So that the horizontal expansion of the city to the four directions and consequently the increase of ecological footprint in this city has led to many changes in use, especially from agriculture and gardens within the city limits to residential and commercial, etc., which causes The destruction of the ecological foundations of the urban environment, the reduction of the capacity to absorb pollution and the intensification of pollution, the lack of green spaces compared to the built-up urban spaces, and finally the reduction of environmental resilience in this city. Accordingly, the purpose of this study is to investigate the trend of changes in the extent and structural pattern of urban land cover based on Explanation of urban ecology structure during the last 34 years using remote sensing techniques and landscape metrics.
Data and Method
The research method in the present study is analytical-descriptive. The data and information required for the research have been collected and processed through library and field studies. In order to identify and create land use maps and with the aim of examining the structural elements of Behshahr city, the images of TM and OLI sensors of Landsat 5 and 8 satellites related to June in two time periods (1986 and 2020) from the US Geological Survey ( USGS) was used. Also for combining bands, processing and classification of satellite images from ENVI 5.3 software, for measuring landscape metrics from Fragstats4.2.1 software, for preparing maps and data of other software, from Arc Gis10.7 software And Arcview3.2 and Excel software has been used to sort the data and prepare the charts.
Finally, using appropriate landscape metrics at two levels (class and landscape) including metrics, MNN, LSI, MSI, MPS, ED, LPI, NP, PLAND, CA Cohesion, changes in the ecological structure of Behshahr were evaluated.
Results and Discussion
In this study, after processing the Landsat satellite images of the studied years (1986 and 2020), land use was classified into four classes: built-up lands, barren and gardens, and green spaces and agricultural lands.
According to the results obtained from land use changes, in 1986, lands built have the highest percentage of area, ie 470 hectares (38.5%) among land uses, and respectively agricultural lands, green space and barren in the next ranks. In 2020, the built-up land has grown significantly compared to 1986 and has reached 788 hectares (65%), and other uses, agriculture, green space and wasteland are in the next categories.
Also, the analysis of Behshahr Landscape metrics during the last 34 years shows that the metric value of the number of patches (NP) has increased from 599 in 1986 to 863 in 2020. In fact, the decrease in their number indicates fragmentation and The fragmentation of large agricultural spots, green spaces and gardens in the study area is due to the increase in urban construction. This reduces their sustainability and ecological performance. The average patches size (MPS) also shows a decreasing trend and has been reduced from 1.96 in 1986 to 1.43. In general, metric changes in the average patches size indicate an increase in degradation and thus a decrease in ecological resources in the study area.
The results of the research also show the fact that the metric value of the average distance of the nearest neighbor (MNN) of Behshahr landscape has increased in the last 34 years and has increased from 79.01 meters in 1986 to 84.69 meters in 2020. This justifies the reduction of connection and continuity of land use patches, especially agricultural lands, gardens and green space.
Conclusion
In general, one of the obvious results of examining the changes in land use maps of the two periods is as follows: Land use made in this period due to increasing population and demand for land and, consequently, urban growth in recent decades, with the most Area changes have increased and increased by (68%). But other land uses have been declining, so that ecological and green lands, agricultural lands (-52%) and gardens and green spaces (-31%). ) And barren lands have also decreased by about -41%.
The analysis of land landscape metrics also clearly shows the effects of human activities and urbanization on the environment, and the results indicate that the landscape of Behshahr city has become more complex, more geometrically complex and geometrically irregular, and with decreasing continuity, It has become more fragmented. In fact, the results of Cohesion, MNN, LSI, MSI, MPS, ED, LPI, NP, PLAND, CA metric analysis show that the studied land uses, especially agricultural lands, gardens and green space in Behshahr in terms of composition and distribution. The space does not have favorable conditions and during the period under study in terms of extent, continuity and nature of the composition and distribution of ecological patches, especially agricultural patches, has undergone a process of severe destruction. So that, changes in the amount of NP (number of patches) and MPS (average patches size) have been indicators of the formation of a downward trend and ultimately the destruction of the system, indicating that reducing the average size of patches, the destruction process in The system shows and in fact a genuine integrated patch has become a number of small patches and has lost its cohesion.
Also, the results of the study of land use continuity metrics (MNN and Choesion) show that in the mosaic network of urban ecological patches, especially agricultural lands, gardens and green space, while eliminating a large part of these patches and changing its use. On the one hand, the average distance between similar patches has increased over the last 34 years, and on the other hand, they do not have the necessary area.continuity and integration to provide ecological services to improve the environmental quality of Behshahr.
Urban Planning
Akram Ali mohammadi; Sadra Motevalli; Azita Rajabi
Abstract
Introduction
The resilient internal transportation system network is a system that is able to absorb the negative effects of turbulences, reorganize them and continue their function. Resilience is directly related to sustainability. The inaccurate usage of available capacities may reduce its` resilience ...
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Introduction
The resilient internal transportation system network is a system that is able to absorb the negative effects of turbulences, reorganize them and continue their function. Resilience is directly related to sustainability. The inaccurate usage of available capacities may reduce its` resilience and provide environment with irrecoverable harms. The main purpose of this research is to recognize the most effective managerial strategies in the resilience of internal transportation network with the emphasis on accessing environmental sustainable development in Tehran region one and provide a schema for it.
Currently, transportation used in urban communities is not stable due to the problems and challenges that occur in it. This instability has manifested itself in the first place in the excessive consumption of energy and fuels, then in the reduction of resources and finally in the increase of air pollution, even globally. Also, major problems and inadequacies in urban transportation affect the economy, society and urban environment as the main indicators of sustainability, which has made it more necessary to pay attention to the issue of sustainability and resilience of urban transportation. Given the existing problems with intercity transportation and low resilience at the city level; The present article seeks to achieve resilience methods of urban transportation by using management strategies to achieve sustainable environmental development in area one of Tehran in 1399.
Method
The method of present study is survey analytic and the sample group were 100 managers and experts of internal transportation network in Tehran region one during 2019 that were participated in purposive sampling method in the study. The data was gathered through researcher self-made questionnaire; through the factor analysis five factors of 1. Organizational capacity improvement (5 items) 2. Systematic management (9 items) 3. Risks` reduction (4 items) 4. Subtraction utilization (5 items) and 5. Information technology usage (3 items) were recognized and afterward, managerial strategies schema in internal transportation system network of Tehran region one was designed and based on that, it is possible to accurately and efficiently plan to improve managerial strategies and functions in internal transportation system network and environmental sustainable development.
Discussion and Results
The current transportation system of region one of Tehran has major limitations such as low share of public transportation, high share of single-passenger cars, increasing distance between business and non-business trips, and inadequate structure and quality of the road network for pedestrian or use transportation. It suffers from cycling, which has led to complications such as traffic congestion, lack of stops, increased pollution, reduced mobility, increased fuel consumption and wasted energy. Policies and measures taken in response to the problems have had little success, mainly due to inconsistencies in planning and implementation on the one hand and a lack of comprehensiveness and foresight on the other. In addition, due to its high population density, the concentration of most administrative and economic centers in it and its special position in terms of geology, this region is one of the most sensitive areas in Tehran. Given the exposure to the threats posed by its location in the region, identifying the most effective strategic management indicators in transport network resilience necessitates research. Considering the current environmental situation of this region, such as the reduction of green space and open spaces, uncontrolled and non-standard construction, increasing the types of environmental pollution in this study has tried to examine and identify the most important and effective indicators. Strategic management strategies in the resilience of the intra-city transportation network In order to achieve sustainable environmental development, a model should be designed to measure and evaluate the resilience of intra-city transportation.
Conclusion
This paper was presented with the title of strategic management model of resilience of urban transportation network with emphasis on achieving sustainable environmental development in area one of Tehran in 1399. In this paper, preliminary indicators were extracted according to the studies, including research background, concepts and theoretical foundations related to the subject, criteria and components of resilience, sustainable environmental development, urban transportation network, and by interviewing elites and Specialists in transportation, traffic and urban management and the use of factor analysis techniques, five criteria: organizational capacity improvement, system management, risk reduction, use of alternative vehicle infrastructure, increasing the use of information technology were identified and prioritized. The results of this research are based on the theories of Cohen's development model with three economic dimensions with the aim of progress, social with the aim of equality and poverty reduction, ecological with the aim of natural resources and prismatic model of sustainability, sustainable development in four dimensions: environmental-economic-social and physical. Emphasizes on reducing ownership and use of personal vehicles, reducing fuel consumption, reducing traffic congestion and various pollutions.
