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  • Author: Olena Bilous x
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Climatic Influence on the Phytoplankton Communities of the Upper Reaches of the Southern Bug River (Ukraine)

ABSTRACT

A total of 98 taxa of algae were observed in phytoplankton, sampled monthly, from the Khmelnitsky monitoring station in the Southern Bug River, Ukraine, between April 2010 and March 2011. Chlorophyta species are the richest taxonomic group with 46 taxa, followed by Bacillariophyta, Euglenophyta, Cyanoprokaryota, Dinophyta, Chrysophyta, Streptophyta, and Xanthophyta. Seasonal dynamics of species distribution in taxonomic divisions shows that the role of Bacillariophyta in communities was high in January-March, which were replaced by greens in March-September. Euglenoids were developed in February-December and bluegreen algae in summer communities only. Strong positive correlations between temperature and species richness was observed. Abundance and biovolume of phytoplankton were maximal in summer, caused mostly by Dolichospermum flos-aquae (Lyngb.) Wacklin, Hoffmann and Komarek and Ceratium hirundinella (O. Müll.) Bergh. The river ecosystem has two periods of trophic levels - high at summer and low at winter. Bioindication characterizes the river as low alkaline and low mineralized with a moderate organic pollution level, revealed aspects of seasonal changes and revealed the main source of organic pollution as flowing from the catchment area during ice melting and rains. Organic pollution indices fluctuate within narrow limits suggesting relative stability of the river ecosystem that is shown also by Shannon indices. The calculated indices, comparative statistics, CCA, and bio-indication analysis exhibits a low pollution level in the Khmelnitsky monitoring station that can be used as a model of aquatic community dynamics under seasonal fluctuation in the southern boreal province climate, applicable for monitoring of the Southern Bug River.

Open access
Green and charophytic algae of the high-mountain Nesamovyte and Brebeneskul lakes (Eastern Carpathians, Ukraine)

Abstract

A study of green and charophytic algae diversity in two high-mountain lakes in the Eastern Carpathians (Ukraine) identified 99 species (109 taxa at species and intraspecific rank) in 35 genera from different ecotopes of the studied lakes. Algal species composition was characterized, and the ecological parameters of the lakes were determined from monitoring data recorded over the last century. Environmental analyses using bioindication methods based only on data on the composition of green and charophytic algae confirmed that the environmental inferences were accurate. Degradation of the Nesamovyte and Brebeneskul lake ecosystems, as compared with their earlier states, was noted.

Open access