خلاصة:
در این تحقیق با استفاده از قابلیت تکنیکهای سنجش از دور تغییرات کاربری اراضی دریاچۀ ارومیه و محیط پیرامون آن در بازده زمانی بیستساله (1989 تا 2019م) با استفاده از تصاویر ماهوارهای سنجنده (MSS، TM وOLI OLI) مورد پایش قرار گرفته است. بررسی تغییرات کاربری اراضی نشان داد: مساحت کاربری کشاورزی از سال 1989 م تا سالتا 2019م افزایش چشمگیری داشته که دلیل آن مساعد بودن منطقه برای زراعت، حفر چاههای متعدد و استفاده از سفره سفرۀ آب زیرزمینی بوده است. همچنین نوسانهای قابل ملاحظهای در سطح آب دریاچه رخ داده است. بهطوری که تغییرات سطح آب از سال 1989م تا 2016م از 5.348 به حدود 2.705 کیلومتر مربع رسیده است. اما از سال 2016م تا 2019م به بهدلیل بارشها 1644کیلومتر مربع افزایش مساحت آبی داشته است. همچنین خطوط ساحلی به بهویژه در شرق و جنوب جنوبشرقی منطقه منطقۀ مورد مطالعه، پسروی بسیار قابل توجهی را نشان میدهد. بهطوری که از سال 1989م تا 2000م مساحت این کاربری 378 کیلومترمربع افزایش داشته است و طی سالهای 2000م تا 2016م مساحت آن همچنان روند صعودی داشته و به 786 کیلومتر مربع افرایش یافته است.
Introduction
Land use is one of the most important biophysical and socio-economic characteristics in any watershed. The science of land change has recently been introduced as one of the fundamental components of global environmental change and sustainable development research. Monitoring land changes is important in future planning and natural resource management. Therefore, the need to detect such changes in an ecosystem is very important. Therefore, the need to detect such changes in an ecosystem is very important to take appropriate action if necessary.. Due to the fact that Lake Urmia is an important ecotourism center in Azerbaijan, with the drying up of the lake, Greater Azerbaijan and all the areas affected by this phenomenon will face a recession of domestic tourists. These factors, in turn, will lead to the migration of residents of the villages of this region to the surrounding cities and social problems in these cities. Its catchment area has been one of the water resources of this area [r11]. But the extent to which these changes, and especially the change in land use, have taken place, requires special study. In general, it is possible to study land use changes in both terrestrial and remote sensing methods. However, in recent decades, with the development of hardware and software facilities for processing satellite images, as well as the ease of access to multi-spectral and ultraviolet images, the use of remote sensing techniques to produce land use maps has become more common. The use of remote sensing technology has a special place in natural resource studies. Multi-time comparison, information updates, digital processing, data diversity, and data transfer speeds have made remote sensing the most important technology in detecting changes.
Methodology
The approach of the present study is developmental-applied and its descriptive-analytical method. According to the subject of the research and in line with the objectives defined in this research, satellite image with the specifications listed in Table (1) and the softwares of Google Earth, ENVI4. 8, ArcGIS10. 2 have been used. To use satellite imagery to perform techniques, all images must have the same coordinates. Remote sensing techniques, especially those used to classify land use and detect changes, are usually monitored and analyzed based on similar pixels in multi-time images; Corrections, images are not properly geometrically and radiometrically corrected, research accuracy is reduced. Thus, the satellite images of 1989, 2000, 2016, and 2019 were returned to the image with an RMS error of 0. 42 pixels, capturing 20 control points from the image surface to the image method. In geometric correction, the ground control points were tried to have a good distribution at the image level so that the mathematical model used to calculate the unknown coefficients in the equation would have less error. To convert the corrected image coordinates to the non-corrected image, a second-order function was used.. In this study, the numerical value reduction method of dark pixels for radiometric correction of images has been used. In this method, a constant value of the total value of the pixels in a given band is reduced to apply radiometric corrections to each satellite image. In the next step, the images were mosaic due to the location of the study area in two women (1368-348)[r12]. Then, using field visits and the global location apparatus, instructional samples for each use (lake, agriculture, salt marsh, other lands) were identified in the study area.
Results and discussion
In this study, three supervised classification methods (neural network, backup vector machine and maximum probability) have been used to extract land use maps. By comparing the accuracy of the classification obtained from the methods mentioned in Table (2) , it was found that the classification method of the backing vector machine with a cap rate of 99. 75% is more accurate than other methods. According to the results of both classification methods of machine vector support and neural network, precise methods for extracting land uses and in separating the phenomena that have close spectral behavior are very successful, especially support vector machine , which. Which was a bit successful.[r13]
Conclusion
In this study, first, images of measuring satellites (MSS-TM-OLI) were used and the map of Urmia Lake, lake landscaping and its surroundings were was extracted by applying supervised classification (support vector machine, neural network and maximum probability).. Comparison of image stratification methods showed that the support vector machine method has more classification accuracy than the other two methods due to its general accuracy and higher capability coefficient. The results also show that satellite imagery has a significant ability to extract land uses. Also, in order to investigate the trend of land use change, maps extracted from satellite imagery in 1989, 2000, 2016 and 2019 were compared. Examination of land use maps in the three mentioned periods showed significant changes in land cover. These changes include: Agricultural land use area has increased significantly from 1989 to 2019 due to the favorable area for agriculture and drilling wells. Numerous and the use of aquifers has been underground. Analysis of Landsat satellite images showed that significant fluctuations in the lakechr ('39') s water level have occurred over the years. So so that the water level changes of Urmia Lake from 1989 to 2016 have increased from 5348 to about 2705 square kilometers. However, from 2016 to 2019, due to heavy cross-sectional rains, it had an increase in water area of 1644 square kilometers. The images also show that the coastline, especially in the east and southeast of the study area, has a significant number of boys. From 1989 to 2000, the area of this land use increased by 378 square kilometers. Also, between 2000 and 2016, its area continued to rise and increased to 786 square kilometers. However, due to the increase in cross-sectional rainfall during 2016 to 2019, the water level of the lake has increased and some of the salt marshes have been submerged and the land use area of the salt marshes has decreased by 838 square kilometers.
ملخص الجهاز:
پذیرش : ٩٩/٦/١١ چکیده در این تحقیق با استفاده از قابلیت تکنیک های سنجش از دور تغییرات کـاربری اراضـی دریاچـۀ ارومیه و محیط پیرامون آن در بازده زمانی بیست ساله (١٩٨٩ تا ٢٠١٩م ) بـا اسـتفاده از تصـاویر ماهواره ای سنجنده (MSS،TM و OLI) مورد پایش قرار گرفته است .
آددجی ٣ و همکاران (٢٠١٥م )، مطالعـۀ ارزیابی روند تغییرات را درگامباری ٤، جنگل محافظت شده رزرو، نیجریه بـا اسـتفاده از سـنجش از دور و تکنیک GIS بررسی کردند در این مطالعه به تعیین میزان روند تغییر در پوشش جنگل رزرو بین سال های ١٩٨٤ تا ٢٠١٤م با استفاده از داده های چندزمانه مـاهواره Land sat پرداختـه شـده است .
مسیبی و ملکی (١٣٩٣)، آشکارسازی تغییرات پوشش و کاربری اراضی را برای شهرستان اردبیل برای ٢٥ سال اخیر انجام دادند، آن ها از سیستم اطلاعـات جغرافیایی و سنجش از دور و روش های آماری ، تغییر سطح کاربری های اراضی مختلـف بـراسـاس تفسیر تصاویر ماهواره های لندست و با استفاده از طبقـه بنـدی نظـارت شـده و الگـوریتم حـداکثر احتمال تشابه بهترین ترکیب باندی در سه دورٔە زمانی ١٣٦٦،١٣٧٧و ١٣٩٠بررسی کردند.
تکنیک های سنجش از دور مخصوصاً روش هایی که برای طبقه بندی کاربری اراضی و آشکارسازی تغییرات استفاده می شود، معمولاً بر اسـاس پیکسـل هـای مشـابه در تصـاویر چندزمانه پایش و تحلیل می شوند؛ از این رو اگر در مرحلۀ پیش پردازش و تصـحیحات ، تصـاویر بـه نحو شایسته ای تصحیح هندسی و رادیومتریـک نشـوند، دقـت تحقیـق کـاهش مـی یابـد (ربیعـی ، ١٣٨٤).