PROLIFERATION OF SPIROGYRA SP. ON THE FISHING NETS IN THE TAGANROG BAY UNDER THE CONDITIONS OF HIGH SALINITY

Since the beginning of the 21st century, the Sea of Azov – Don Basin has been affected by lowwater processes, which lead to the filling of the Don Delta and the adjacent water area of the Taganrog Bay of the Sea of Azov with atypical slightly salty and brackish waters. As a result, there is a transformation of the thermohaline, trophic, and biocenotic structure of the reservoir, degradation of the ichthyofauna, and radical restructuring in both planktonic and benthic biotopes. The consequences of these trends more often have the scale of a dangerous natural phenomenon. This paper describes a new phenomenon for the reservoir – the fouling of fishing nets with filamentous algae from the genus Spirogyra in the eastern shallow part of the Taganrog Bay. In the published sources, there is no data on the presence of Spirogyra in the fouling of the studied reservoir. The study of samples collected in May 2021 indicated that the morphological features of spirogyra fertile filaments corresponded to the description of Spirogyra cf. decimina. In addition to S. decimina, two more morphs are distinguished based on the morphological differences of vegetative thallome. The paper presents the results of qualitative analysis and quantitative assessment of macroalgae fouling of fishing nets, as well as micrographs of various stages of development of the studied algae. The article lists the main environmental factors that cause the mass development of representatives of the genus Spirogyra and analyzes the hydrological conditions of the Taganrog Bay with the intensive proliferation of algae on the nets.

, filamentous algae, , fouling of fishing nets, Taganrog Bay, Sea of Azov, salinization