ارزیابی و پایش روند گسترش فیزیکی سی ساله شهر اردبیل با استفاده از تصاویر ماهواره ای (مقاله علمی وزارت علوم)
درجه علمی: نشریه علمی (وزارت علوم)
آرشیو
چکیده
در طی دهه های اخیر اراضی حاشیه ای شهرها که اغلب از اراضی کشاورزی مرغوب و باغات می باشند، تغییر کاربری داده شده اند که این تغییرات به عنوان یکی از عوامل مهم و مؤثر چالش های اجتماعی و زیست محیطی به شمار می آیند. امروزه فن آوری سنجش از دور و سیستم اطلاعات جغرافیایی به دلیل قابلیت هایی مانند قدرت نظارت و تفکیک زمانی و مکانی بالا، تصاویر مکرر، کاهش هزینه ها و ... به طور مؤثر برای شناسایی و تعیین مقدار تغییرات کاربری اراضی و اثرات آن بر محیط زیست و نظارت و مدیریت بهینه شهرها استفاده می شوند. این تحقیق با هدف ارزیابی گسترش سی ساله شهر اردبیل با استفاده از تصاویر لندست می باشد. ابتدا تصاویر مربوط به سال های 1987، 2000 و 2017 تهیه شدند. سپس با استفاده از الگوریتم های ماشین بردار پشتیبان، حداکثر تشابه و شبکه عصبی مصنوعی شهر اردبیل به شش کلاس کاربری (مناطق مسکونی، اراضی کشاورزی با پوشش، اراضی آیش، اراضی بایر، جنگل شهری و آب) طبقه بندی شد. در نهایت دقت طبقه بندی هر کدام از الگوریتم های مورد استفاده بررسی شد. نتایج نشان داد که الگوریتم ماشین بردار پشتیبان دقت بالاتری نسبت به دو الگوریتم دیگر دارد. بر همین اساس، نقشه حاصل از الگوریتم ماشین بردار پشتیبان نشان داد که مساحت اراضی ساخته شده اردبیل از 20/0223 کیلومتر مربع در سال 1987 به 41/5854 کیلومتر مربع در سال 2017 افزایش داشته است. با توجه به نتایج حاصل از این تحقیق می توان بیان نمود که شهر اردبیل در بازه زمانی سی ساله گسترش نامتوازنی داشته است. بنابراین به منظور دستیابی به توسعه بهینه این شهر توصیه می شود با استفاده از نقشه های به دست آمده، در صورت امکان با زون بندی بهینه شهر، تجدید نظر کلی در تهیه طرح جامع ، برنامه ریزی و مدیریت این شهر انجام گیرد، چرا که ارزیابی روند توسعه شهری و آگاهی از الگوهای تغییرات کاربری اراضی به منظور مدیریت و برنامه ریزی بهینه شهرها ضروری می باشد.Evaluation and monitoring of the thirty-year physical expansion process of Ardabil city using satellite images
Extended Abstract
Introduction
awareness of the type and percentage of land use and cover types is a fundamental requirement for understanding and management of a region. The growth of urbanization and increasing use of resources due to the development of the required facilities in urban life has changed the pattern of demand for resources and lands, changing the nature and quality of agricultural land, Historical and natural landscapes and surrounding urban areas through the transformation of these lands into residential areas. In recent decades, the suburban lands of cities have changed their use due to the urbanization process and the need of citizens for new residential areas and the surrounding lands, which are often high quality agricultural lands and gardens. This, along with things like industrialization and changing rainfall patterns, has destroyed the cover and natural environment of cities, and thus has posed many social and environmental challenges and endangered sustainable urban development, and as a result of this process, a lot of ecological pressure has been imposed on the natural ecosystem of the region. These changes are considered as one of the important and effective factors of social and environmental challenges. Today, remote sensing technology and GIS due to capabilities such as high monitoring power and resolution, frequent images, cost reduction, etc., To effectively identify and quantify land use changes and their effects on the environment and monitoring And rapid management of the growth and development of cities are used. In the present study, the aim is to evaluate the urban development of Ardabil in the last 30 years using remote sensing technology and satellite images.
Materials & Methods
Landsat satellite imagery was used to prepare land use maps for 1987, 2000 and 2017. In order to ensure the quality of data and bands, the images used in this research were first corrected for radiometric errors in ENVI 5.3 software environment. Then RVI, SAVI, NDVI, BI and IPVI indices were extracted. In the next step, maps related to filter texture, vegetation delineation and tasseled cap were prepared. At the end of this step, all the extracted layers were merged with the corrected image bands. Then satellite imagery using support vector machine algorithms, maximum similarity and artificial neural network with acceptable accuracy in six user classes (residential areas, covered agricultural lands, fallow, barren lands, urban forest and water) floor were classified. Then, to evaluate the classification accuracy, the overall accuracy and kappa coefficient were calculated for each of the maps.
Results & Discussion
According to the values of overall accuracy and kappa coefficient, which in 1987 for the support vector machine algorithm were 90% and 0.86, respectively, the maximum likelihood was 84.5% and 0.78, and the neural net was 90.5% and 0.87, respectively, in 2000. Overall accuracy and kappa coefficient for support vector machine algorithm 92% and 0.90, maximum likelihood 92.5% and 0.90 and neural net 92.6% and 0.90, and in 2017 overall accuracy and kappa coefficient for backup vector machine algorithm 90.6% and 0.88, maximum likelihood of 82.8% and 0.78 and for neural net were 88% and 0.85, it was found that the support vector machine algorithm has the highest accuracy compared to the other two algorithms. According to the results obtained from the study of satellite images classified by the support vector machine algorithm, the area of land built in Ardabil has increased from 20.023 square kilometers in 1987 to 41.554 square kilometers in 2017.
Conclusion
In general, it can be concluded that to evaluate the trend of urban sprawl and awareness of land use change patterns for optimal management and planning of cities, the use of satellite images, especially Landsat images is a suitable and low cost option. The results also showed that the rate of land use change to land uses is increasing and since land is the main element in urban development, so control how to use it and also calculate the real need of the city for land, to In order to provide different uses is effective. As a result, according to the findings of this study, in the absence of proper planning for this city due to favorable lands for urban development around the city, in the not too distant future, witness the destruction of agricultural lands around the city of Ardabil and conversion they will be residential areas.
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