نوع مقاله : پژوهشی
نویسندگان
1 دانشجوی دکترای سازههای آبی، گروه مهندسی آب، دانشگاه علوم کشاورزی و متابع طبیعی گرگان، گرگان، ایران
2 گروه مهندسی آب، دانشکده مهندسی آب و خاک، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
3 استاد گروه مهندسی آب، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Monitoring morphological changes in meandering rivers, particularly in inaccessible areas or those lacking field data, has always faced operational challenges. Although remote sensing technology offers a promising solution to these challenges, most previous studies have focused on wide rivers, and its effectiveness for rivers with an average width of less than 50 meters has not been evaluated. This research aims to evaluate the accuracy of remote sensing methods in estimating migration rates and extracting river centerlines, using the Atrak River as a case study. In this study, using Sentinel-2 satellite images (from 2016 to 2021), six spectral indices (NDVI, NDWI, MNDWI, AWEI, EWI, WIR) were compared to extract the water surface of a section of the Atrak River near Korand and Hootan villages. After image preprocessing, the river centerline was extracted in QGIS, and its accuracy was evaluated using RMSE, length difference percentage, and spatial agreement with Google Earth reference data. Calibration results for 2016 showed that the MNDWI index, with the lowest error (RMSE = 6.09 m), the smallest length difference (0.47%), and the highest spatial agreement (94.13%), was the most accurate index for centerline extraction. Verification of this index for 2021 also confirmed its acceptable performance, with a length difference of 1.45% and an agreement of 85.95%. The findings clearly demonstrate the effectiveness of remote sensing and the superiority of the MNDWI index for quantitative and accurate monitoring of morphological changes in medium-width rivers.
کلیدواژهها [English]
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