پایش تغییرات کاربری اراضی شهرستان قائم‌شهر با استفاده از RS و GIS

Introduction: Land use changes are one of the important issues in regional and development planning. Considering the advantages and capabilities of satellite data, this technology can be of great help in identifying and discovering these changes; In this study, land use changes in the Ghaemshahr region were evaluated over a 22-year period.To  conduct this research, images from the 2001 ETM+ sensor, 2014 and 2023 OLI sensor of the Landsat satellite were used. The main goal of this research is to investigate and reveal land use changes in the city of Ghaemshahr, located in Mazandaran province, between 2001 and 2023, where a large part of its forests have been destroyed for various reasons in recent years; since at least two data series from different time periods are required to monitor land use changes using satellite images.
Material and methods: In this study, data from the ETM+ and OLI sensors of the Landsat satellite were used to monitor the trend of land use and land cover changes in Ghaemshahr County in three time periods: 2001 to 2014, 2014 to 2023, and finally to examine the 22-year changes from 2001 to 2023. The images presented in this system were atmospherically, radiometrically, and geometrically corrected, and the Jeffreys-Matousita criterion, which is a type of test to ensure the separation of classes defined using ground control samples, was used. And the samples were re-corrected and the best band combination was selected, and the study area was classified into six land use classes. In addition, the minimum separability using the Jeffreys-Matuseita criterion is zero and its maximum is 2. The results of class separability were extracted for the years 2001, 2014 and 2023.
Results and discussion: Based on the results of the matrix table, the overall classification accuracy obtained from the ETM+ sensor data for the year 2001 was calculated to be 89.2 and for the OLI sensor data for the years 2014 and 2023 it was calculated to be 90.3 and 95.8. Also, the kappa coefficient for the years 2001, 2014 and 2023 is 0.85, 0.88 and 0.91, respectively. In terms of the area changed over the 22-year period, the garden and residential land classes have increased the most, so that the area of ​​these classes has increased from 22.5 and 12 percent of the total area of ​​the study area in 2001 to 43.5 and 20.8 percent in 2023, respectively, which means an increase of more than 7,694 hectares in garden lands and 3,139 hectares in residential lands. Also, the agricultural land class had the largest decrease with a decrease of 11,102 hectares and 29.1 percent. This decrease is due to the conversion of agricultural land to garden and residential land in the study area. Other classes of water, barren areas and forests decreased by 0.3, 0.2, and 0.4 percent, respectively. In general, the use of satellite images to prepare maps of land use and their changes is essential in environmental resource management planning.
Conclusion: The results of this study indicate that the area of ​​forested lands has decreased and over time, the land cover pattern and consequently land use have undergone fundamental changes and transformations, and human factors have played the largest role. In Qaemshahr County, a significant portion of the conversion of garden and agricultural lands is related to the replacement of residential use in place of these lands.