Impact on the marine environment of phytoperifiton functioning in Black Sea ecosystems of different ecological status

Abstract

The paper considers the influence of phytoperiphyton functioning on changes in the quality of the aquatic environment in the Black Sea coastal areas with different categories of ecological status class. According to the results of long-term studies of phytofouling of solid substrates under conditions of various categories of ecological state: Moderate – Odessa coast and Poor – delta of the Danube River, the features of its development and the possibility of changing the quality of the aquatic environment are presented. The seasonal dynamics of the structural-functional indicators of phytofouling (biomass, specific surface area, production, oxygen evolution, nitrogen and phosphorus binding) in water bodies with different ecological state was revealed. It is shown that the placement of ecopositive structures in the coastal zones of the sea with the ecological status Poor will affect the quality of the marine environment several times more intensely than in the status Moderate, due to the higher intensity of the functioning of plant communities. It was found that in the waters with the status class Moderate, macrophytes from the divisions Chlorophyta and Rhodophyta prevail, in the waters with a lower status Poor – species from the divisions Chlorophyta and Cyanobacteria, which indicates an increased trophicity of the water body. According to the predominance of species in a water body with an ecological status of Moderate, four associations of macrophytes and micro-epiphytes are distinguished, the growth of which is confined to different depths – 0–3.0 m, 4.0–6.0 m, 7.0–8.0 m, 10.0–11.0 m. For the development of communities of macrophytes and microepiphyton, the optimal depths are from 0 to 3 m, at which the highest values of surface indices, production, biomass, nitrogen and phosphorus binding are observed. With increasing depth, the average ecological activity of edificators of macrophytobenthos associations decreases from 30.79 to 24.52 m2∙kg-1.