Fig. 2. Delineation of threshold values for the boundaries of the " Batak " Reservoir an example on the NDWI-index, Sentinel 2 L1C 2022-11-01
Table 3. Boundaries of the Batak Reservoir determined by different methods from satellite images Sentinel 2 Level 1C 2022-11-01 and from Sentinel 2 Level 1C 2024-07-28
Sentinel 2 Level 1C 2022-11-01 площ( km 2)
Sentinel 2 Level 1C 2024-07-28 площ( km 2)
NDWI 19.02 NDWI 18.22
Sentinel WM 18.82 Sentinel WM 18.03 WRI 18.75 WRI 17.96
OBIA 19.06 OBIA 18,24
Водно тяло *( по МЗХ)
20.78 Водно тяло *( по МЗХ)
20.78
* data from the Ministry of Agriculture and Food, Bulgaria( 2022 and 2023)
Fig. 3. K-means clusters( Sentinel 2 L1C 2024-07-28)
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