Functional Groups of Phytoplankton and Their Relationship with Environmental Factors in the Restored Uzarzewskie Lake

Abstract

Uzarzewskie Lake is a small, postglacial lake, located in western Poland. The lake is under restoration treatment since 2006. At first, iron treatment was done for 2 years. In the second stage, spring water was directed into the hypolimnion in order to improve water oxygenation near the bottom sediments. The purpose of our research was to determine changes in the contribution of functional groups to the total number of taxa and total biomass of phytoplankton due to changes in the physical and chemical characteristics of the restored lake. Phytoplankton composition was analyzed in three periods: (1) before restoration; (2) during the first method of restoration; and (3) when the second method was implemented in the lake. Epilimnetic phytoplankton was sampled every year monthly from March to November. The relationship between phytoplankton groups and environmental factors (water temperature, ammonium nitrogen, nitrate nitrogen, dissolved phosphorus, conductivity and pH) was examined, using the canonical analyses. The redundancy analysis indicated that the temperature, dissolved phosphates concentration, ammonium nitrogen and pH were the main determining factors of the phytoplankton community dynamics. During the study, 13 coda dominated the phytoplankton biomass. Cyanobacteria of the codon H1 with such species as Aphanizomenon gracile, Dolichospermum planctonicum, D. viguieri dominated the phytoplankton community before restoration. S1 group consisting of Planktolyngbya limnetica, Limnothrix redekei and Planktothrix agardhii mostly dominated during the period in which the first method was used. Improvement of water quality due to restoration efforts in the third period caused dominance of other groups, especially J (Actinastrum hantzschii and other Chlorococcales), C (Asterionella formosa and other diatoms), Y (Cryptomonas marssonii and other cryptophytes), Lo (Peridiniopsis cunningtonii and other dinophytes) and X2 (Rhodomonas lacustris).

Phytoplankton succession in the anthropogenic and climate ecological transformation of freshwater ecosystems

“…Natural and anthropogenic flows are interconnected, which causes difficulties in distinguishing the actual "natural" and "anthropogenic" cycles (Odum, 1986). A number of authors have shown that the changes caused by the inflow of biogens into continental waters create conditions for the process of anthropogenic eutrophication, causing the restructuring of aquatic ecosystems (Kozak et al, 2020). There is also a great number of publications on the consequences of river-flow regulations, which caused changes in the hydrochemical and hydrophysical properties of waters (slowing of water exchange, decrease in the flow rate, changes in the N/P ratio, ionic composition) and analyses of factors determining phytoplankton succession.…”

Phytoremediation of CYN, MC-LR and ANTX-a from Water by the Submerged Macrophyte Lemna trisulca

“…It was shown that a high conductivity (1500 µS·cm −1 ) had a neutral or positive effect on growth for the R. raciborskii strain [ 43 ]. In other papers, it was shown that the water conductivity affected the abundance of selected microorganisms in both freshwater and seawater [ 44 , 45 ]. In our experiments, the initial conductivity of the medium was 760 µS·cm −1 , and without the addition of any living organism within 14 days it was stable ( Figure 3 A).…”

Analysis of Performance of the Wind-Driven Pulverizing Aerator Based on Average Wind Speeds in the Conditions of Góreckie Lake

“…The advantage of moderate oxygenation over intensive oxygenation consists in limiting the mineralization of organic matter in bottom sediments, enabling nitrification and denitrification processes that result in the removal of nitrogen into the atmosphere, thus maintaining the positive redox potential at the sediment-water interface, which allows phosphorus retention. As a result, the nitrogen ammonium is oxidized to the form of N 2 , enabling the annamox process to occur [20,27,28,[31][32][33][34][35][36]. The pulverizing aerator uses only energy from a wind turbine (Savonius system) to drive the pulverizing unit.…”