LONG-TERM CHANGES IN THE AREA OF LAKES ON THE BAR OF THE TYLIGULSKYI LIMAN (BLACK SEA)

Abstract

Problems Statement and Purpose. The estuarine area of Tyligulskyi Liman is located within the limits of north-western limans coastal area between the Odesa bay and Berezans’kyi Liman. Tyligulskyi Liman is separated from the sea by a wide sandy-shell bay-bar, in which an artificial liman-sea connecting channel is laid. The bay-bar of the Tyligulskyi liman is one of the most powerful sea-land contact zones in the region. The Tyligulskyi Liman and its bay-bar are officially recognized as Ramsar wetlands. The need to study and protect the bay-bar is associated with both its international status of the wetlands and the preservation of natural conditions and resources for the planning of nature management and sustainable development of the geosystem. The Lakes of the bay-bar were insufficiently studied in comparison with biota and hydrology of the adjacent part of the Black Sea, the Tyligulskyi Liman and the connecting channel. Data & Methods. The study of the water bodies of the Tyligulskyi Liman bay-bar was carried out by field and cameral methods. Field mapping and survey work were carried out, sediment samples were taken. The cartographic method made it possible to analyse the cartographic materials of 1793–1982 edition suitable for their decoding and analysis. GIS methods were used to process cartographic images, satellite images and field measurements. Cameral work was performed in ‘Saga Gis’ software. To study the numerical values of the dynamics and development of the water bodies at the Tyligulskyi Liman bay-bar, the total lake percentage is calculated. Results. The water bodies at the Tyligulskyi liman bay-bar exist and develop during all its forming time. In their development, they experienced significant changes along with changes of the bay-bar caused by the channel connecting the Black Sea with the Tyligulskyi Liman, individual lakes to an artificial channel. According to the genesis of the lake basin are presented on the bar the remaining coastal lakes, anthropogenic and anthropogenic-transformed. At the present stage, the water bodies’ development is determined by operation frequency of the artificial connecting channel, level fluctuations, up and down surges. The inflow of estuary water into the water bodies of the bay-bar is constant at all stages of their development, in contrast to its inflow from the sea. On the Tyligulskyi liman bay-bar, there are constantly three water bodies: the northern lake, a chain of central and eastern lakes, and the channel. Commissioning of the channel connecting the Black Sea with the Tyligulskyi liman has led to an increase in the total lake percentage of the bay-bar from 3.9–11.1% in its natural state to 20.4–26.5% at present. With all its insignificant parameters, the connecting channel performs a system-forming function – it provides water exchange and the functioning of the natural complexes of the inner part of the Tiligul bay-bar. Further research the lakes on sand bar will provide an understanding of the functioning of the Tyligulskyi Liman bay-bar from a geosystem point of view, which will contribute to sound rational nature management at the bay-bar, preservation of natural diversity and sustainable development of the territory.