PHYTOPLANKTON OF RECREATIONAL PONDS OF ZHYTOMYR DISTRICT

Abstract

The structural and functional characteristics of the phytoplankton of recreational ponds of Stanyshivskyi and Pryazhivskyi (Zhytomyr district, Zhytomyr region) are presented, their bioproduction potential is clarified, and water quality is assessed. It is shown that the phytoplankton of ponds has a rich species composition. In the seasonal distribution of algae, the maximum number of specific and intraspecific taxa is observed in the autumn period. In all seasons, the Chlorophyta, Bacillariophyta and Euglenozoa divisions play a leading role in the formation of the species and intraspecies richness of water bodies, and in the Stanyshiv pond – also Cyanoprocaryota in the summer. According to the biomass of phytoplankton, the water quality of the reservoirs corresponds to the III class of water quality of the «slightly polluted» category. In the phytoplankton of ponds, the leading role belonged to planktonic-benthic forms; to cosmopolitan species by geographical location; alkaliphiles and indifferents in relation to pH; to oligohalobs-indifferent in terms of halobity; stationary and flowing forms. According to the level of organic pollution according to the Pantle-Buk system in Sladechek’s modification, the water quality corresponds to the II class of water quality. Watanabe’s assessment of organic water pollution showed a predominance of Eurysprobes in the ponds. The average values of the Shannon index, calculated for the phytoplankton of the Pryazhivskyi and Stanyshivskyi ponds, indicate the predominance of the oligodominant structure of algal communities. The high intensity of photosynthesis in ponds is typical for reservoirs and watercourses of the Ukrainian Polissia zone. The ratio of the integral indicators of the primary production of phytoplankton and the destruction of organic matter indicates the predominance of the autotrophic phase in the ponds. A comparison of the structural and functional characteristics of phytoplankton in recreational ponds with natural (rivers and lakes) and anthropogenically altered water bodies (reservoirs) proved the common common mechanisms of formation and functioning of their autotrophic link. A distinctive feature is the lower values of the informative diversity of phytoplankton compared to other types of water bodies, as indicated by the values of HB. We believe that this is due to the specifics of artificially created reservoirs.