SATELLITE MONITORING OF THE DYNAMICS OF THE WATER SURFACE AREA OF LAKE SOLONETS-TUZLY, BLACK SEA LOWLAND, UKRAINE (FOR THE YEAR 2024)

Abstract

The article presents the results of satellite monitoring of seasonal dynamics of the water surface area of Lake Solonets-Tuzly, located within the Black Sea Lowland, near the mouth of the Berezan River, during 2024.Sentinel-2 satellite images were used for the analysis, based on which the NDWI index was calculated and composite images in the SWIR range were formed. The obtained data were processed in ArcGIS Pro, Google Earth Pro, and RStudio environments. Based on the analysis of satellite images, calculations of the water surface area of the studied lake were made for each month of 2024. The results obtained indicate significant seasonal fluctuations in the lake's area, from a maximum area of 5.53 km² (January) to complete drying up and the formation of a salt marsh (August). The maximum area of the lake was observed in winter, while in spring, the area of the lake decreased significantly by the beginning of summer. At the beginning of summer, the lake area temporarily increased, but then rapidly decreased until it completely dried up in August. In autumn, the lake area slowly but steadily increased until December.The average water surface area of the lake in 2024 was 2.98 km², with an amplitude of 5.53 km². Spatial analysis revealed heterogeneity in the drying of the lake basin: the northern part lost water faster and therefore dried up completely by July, while the southern part, especially in the center, remained wet for a longer period and dried up completely only in August. The presented heterogeneity of the lake surface drying is due to its morphological conditions.The NDWI index showed a high correlation with the area of the reservoir, confirming its effectiveness for monitoring small, unstable reservoirs. SWIR composites, in turn, proved useful for visual assessment of moisture levels but were not accurate enough for quantitative analysis. The study demonstrates the effectiveness of using satellite indices to monitor water dynamics in small salt lakes under conditions of climate change and anthropogenic impact.