Fig. 5. Batak Reservoir( SW-part: Photo 1. Golaka Island; Photos 2, 3 and 4: Reservoir limits in red color- 19.09.2024); boundary changes ̶ in orange and yellow color
4. CONCLUSIONS
Inland surface water bodies are important components of the hydrosphere and the aquatic ecosystems. Establishing their extent and changes due to climate change and anthropogenic activities is crucial for many scientific and practical purposes, such as water quality analysis, water consumption assessment, and water resource management.
The water index-based, threshold-based, and object-oriented analysis approaches were selected for the study.
The obtained results show a good correlation between these indices( NDWI, SWM, and WRI) and OBIA segments for the selected optical satellite images, with small differences in the extracted area of the Batak Reservoir.
Utilizing satellite imagery to extract the boundaries of surface water bodies can be very useful for longterm monitoring. The quick and accurate determination of their boundaries is an important tool for water resource management.
The results provide valuable spatial information on the changes in the Batak Reservoir area, which cannot be identified by only measuring its water levels. This highlights the usefulness and effectiveness of processing satellite imagery data, which can be applied to enhance the quality of existing data sets available from the East Aegean River Basin Directorate( Plovdiv). Also, the analysis of satellite imagery data can be used for long-term monitoring of the spatial and temporal changes in the boundaries of the Batak Reservoir. It can also be helpful for its water resource management.
5. ACKNOWLEDGMENTS
This research has been carried out in the frame of the project“ Models of anthropogenic impact on the natural environment at river basin scale( ModAiNe)”, funded by the National Science Fund, Ministry of Education and Science( Bulgaria), competition for financial support for basic research projects – 2022( contract no КП-06-Н64 / 6, signed on 15.12.2022).
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