Preliminary Assessment of Ecological Status of the Siversky Donets River Basin (Ukraine) Based on Phytoplankton Parameters and Its Verification by Other Biological Data

Abstract

The river basin of Siversky Donets is of great scientific interest since this river runs through a territory with heavy industry (in particular, coal mining, chemical processing and metal industries). Within the basin, rivers of different sizes were explored (small, medium, large and extra-large) that flow through siliceous and calcareous rocks on the same elevation (lowland—below 200 m a.s.l.). Phytoplankton, as one of the Biological Quality Element, was used to perform the assessment of ecological status of the water bodies within the Siversky Donets river basin in 2019. The state monitoring program based on the updated approaches has been implemented in the river basin for the first time. The composition of phytoplankton species in the basin comprised 167 species (168 intraspecies taxa), mainly Bacillariophyta (63%) and Chlorophyta (22%) with the presence of other species (Cyanobacteria, Charophyta, Chrysophyta, Dinophyta and Euglenophyta). High species diversity and divisions amount are a distinctive property of the smaller rivers, while the bigger rivers show lower number of divisions. The “bloom” events, which are important ecological factors, were not detected in the Siversky Donets river basin. Algal species composition in plankton samples of the basin was identified and series of ecological parameters, such as habitat preferences, temperature, pH, salinity, oxygenation and organic water pollution according to Watanabe and Sládeček’s index of saprobity (S) trophic state and nitrogen uptake metabolism were analyzed. The ecological conclusions were also verified by a canonical correspondence analysis (CCA). The significance of the Canonical Correspondence Analysis (CCA) results was estimated of by a Monte-Carlo permutation test. The high concentrations of inorganic phosphorus compounds (permanganate index (CODMn)) and nitrite ions favored the diversity of Chlorophyta and Cyanobacteria diversity correlated with the levels of bicarbonate and CODMn. High diversity of diatoms was facilitated by the total amount of dissolved solids and chemical oxygen demand (COD). It was found that low water quality could be associated with conditions leading to predominant growth of the mentioned groups of algae. According to the analysis, the highest water quality was characterized by balanced phytoplankton composition and optimal values of the environmental variables. The sites with reference conditions are proposed for future monitoring.

Impact of hydrotechnical construction on aquatic ecosystems of the Kiliia branch of the Danube Delta

“…One of the ways of implementing the purposes of this document is assessment of ecological condition and risks that could hinder its improvement (Solimini et al, 2008;Allan, 2012). Measures of the Water Framework Directive of the EU have already been introduced for many aquatic objects of Europe: rivers (Spänhoff et al, 2012;Bilous et al, 2021;Skoulikidis et al, 2021), lakes (Søndergaard et al, 2005;Latinopoulos et al, 2021;Ntislidou et al, 2021), transitional (Pérez-Ruzafa et al, 2007;Cacciatore et al, 2019;Facca, 2020) and coastal (Giovanardi et al, 2018;Gerakaris et al, 2022) water, including river deltas (Newton et al, 2014;Stoica et al, 2014;Goulding et al, 2021).…”

Indication of Long-Term Changes of Algae Communities in a Hydrologically Transformed Estuary Sasyk, Black Sea, Ukraine

“…To determine the environmental factors affecting the diversity of phytoplankton in the Sasyk, a few studies were performed. Bioindicator analyses were performed according to [22], based on species-specific ecological preferences of the revealed algae and cyanobacteria [23][24][25], with the combination of species with similar ecological properties to indicator groups reflecting the response of aquatic ecosystems to habitat, pH, oxygenation, water mass dynamics, salinity, trophic state, and the class of organic pollution. The analysis of bioindicators included several steps.…”

Freshwater as a Sustainable Resource and Generator of Secondary Resources in the 21st Century: Stressors, Threats, Risks, Management and Protection Strategies, and Conservation Approaches

“…In fact, practically the entire basin of the Siverskyi Donets River and rivers of the northern coast of the Sea of Azov are affected by the mine waters. The environmental effects can be assessed only after the hostilities’ cessation by comparison of data with those obtained before the wide-scale Russian aggression [ 244 ].…”