Katarzyna Glińska-Lewczuk

The effect of metals accumulated in reed (Phragmites australis) on the structure of periphyton.

Studies on trace elements in reed stands and limiting effect of the reed substrate on the periphyton structure were performed in various aquatic ecosystems of Greece during the summer and autumn of 2006. The analysed factors were concentrations of chemical elements (cadmium, lead, zinc, chromium, nickel, copper, cobalt, iron, manganese, potassium, sodium, calcium, magnesium) in reed shoots as well as the density of zooperiphyton and phytoperiphyton taxa. The relationships between metal concentrations and periphyton structure were determined with the use of the multivariate methods Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA) and RDA (Redundancy Analysis). The results showed that bioaccumulation of lead and cadmium in the reed had the most negative influence on zooperiphyton species, while low concentrations of alkali metals favoured the occurrence of Cyclopoida, Cladocera (Chydorus sp.) and Oligochaeta (Neis sp.). A considerable resistance to toxic heavy metals characterised Cyanophyta representatives and, partly, colonial Bacillariophyta. High concentrations of alkali metals supported the presence of unicellular Bacillariophyta but diminished the densities of colonial Bacillariophyta and Chlorophyta of the genus Scenedesmus.

Effects of lateral connectivity on zooplankton community structure in floodplain lakes

Hydrological conditions are responsible for the changes in lateral connectivity between the main river channel and the floodplain lakes, a factor controlling zooplankton abundance and diversity. We tested the hypothesis that the degree of connectivity between the aquatic habitats and the river channel governs the zooplankton densities and community structure. Abundances, community composition and species diversity of zooplankton were analysed against the gradient of lakes’ connectivity and the water quality parameters under a natural flood pulse in the Biebrza River (North-Eastern Poland). Our findings revealed that the water level fluctuations directly affect the availability of nutrients, aeration, what in turn controls the densities and biovolumes of zooplankton communities. Along with the increase in the lake isolation, the taxonomic diversity of zooplankton decreased, while the eudomination of taxa indicative of advanced trophy (Rotifera) was observed. Qualitative parameters, as number of species, diversity and richness, were significantly higher at mean water levels, which supports the intermediate disturbance hypothesis. The sensitivity of the zooplankton community to variable hydrological conditions and lateral connectivity gradient demonstrates its potential as an unexploited indicator of any habitat changes in the aquatic ecosystems.

Effects of a Floodplain Lake Restoration on Macroinvertebrate Assemblages — A Case Study of the Lowland River (The Słupia River, N Poland)

ABSTRACT: A study on the response of macroinvertebrate assemblages to the restoration of hydrological connectivity of an oxbow lake through the channel excavation is presented. The study included a five-year environmental monitoring (hydrological, hydro-chemical measurements and invertebrate sampling) carried out in the years 2008–2009 and 2011–2012 in the floodplain of the Słupia River (N Poland). The results allowed for assessing ecological effects of the hydrotechnical treatments (re-opening of an old river bed, declogging and installation of wooden deflectors) applied in the oxbow restoration. The results confirmed the preliminary hypothesis that the level of hydrological connectivity determines the dynamics of invertebrate fauna communities in river-floodplain systems. Analysis of the data revealed that such reconnection considerably influenced the structure of hydrobionts by altering abiotic habitat conditions. Effects of radical changes in the habitat morphology and hydrodynamic conditions and monitoring of macroinvertebrate assemblages preformed in the restored lake indicated a significant instability of the ecosystem soon after the treatment, what was confirmed by the results of canonical analysis, in which 50% of the total variance remained unexplained. Among factors analysed, water quality parameters explained 21.4% of the total variance in macroinvertebrate communities. However, the hydrobionts showed a significant instability with respect to variable hydrological conditions (flow through the lake) what contributed to a low share of water flow along the oxbow in explaining the total variance. The analysis of long-term changes that occurred in the studied ecosystem showed that the restoration of full hydrological connectivity brought only a short-term increase in benthofauna abundance. The most distinct reorganization in the structure of macroinvertebrate communities was observed in the first year after the reconnection while the consecutive four years brought only insignificant changes, mainly the appearance of a few species, mainly molluscs. Our investigation suggests that the taxonomic composition of macroinvertebrates in the studied oxbow lake having the only one-arm opening, before the improvement of hydrological connectivity, seemed to be more stable and optimal for this kind of habitat, than after the hydrotechnical works, when the ecosystem became passable due to both-arms connections to the river channel. Therefore, semi-lotic oxbows, connected to parent rivers only with one arm, can be properly functioning aquatic ecosystems in river floodplains.

The use of benthic macroinvertebrate metrics in the assessment of ecological status of floodplain lakes

Five oxbow lakes of the Łyna River, located in an agricultural area, were studied seasonally in 2005 and 2008. The EPT index (abundance of Ephemeroptera, Plecoptera and Trichoptera larvae), as well as their proportion to Chironomidae indicated that groups sensitive to environmental conditions occurred at low abundance in relation to the different hydrological types of oxbow lakes. The Family Biotic Index, the Biological Monitoring Working Part index adapted to Polish conditions and the Average Score Per Taxon (ASPT) revealed low water quality regardless of the level of hydrological connectivity. In turn, the indices of biodiversity Margalef (d) and probability of interspecific encounters indicated good or satisfactory water quality. The pH correlated positively with the total abundance of aquatic invertebrates, while lower macroinvertebrate abundance was observed in turbid waters of lentic oxbows with a high content of total dissolved solids. Canonical correspondence analysis showed that hydrological connectivity was the main factor responsible for the value of monitoring indices, followed by the physical and chemical parameters of the local environment. Among the indices used, it was ASPT-PL that grouped the studied oxbow lakes according to their hydrological types and seems to be the best index. This study shows that the structure of invertebrate communities inhabiting oxbow lakes reflects physico-chemical conditions of water and can be a valuable source of monitoring data, indispensable to the management and protection of these important aquatic ecosystems.

From isolation to connectivity: the effect of floodplain lake restoration on sediments as habitats for macroinvertebrate communities

The present study aimed to identify potential macrozoobenthic habitat indicators of the ecological success of restoration projects. As a part of the complex restoration project in the Słupia River floodplain (N Poland), the connectivity between three oxbow lakes and the river channel was re-established to improve biodiversity of the floodplain area, including bottom fauna. Following restoration, changes in the dynamics of flowing water and water levels induced the transformation of oxbows from plesiopotamal (lentic) to eupotamal (lotic) and subsequently to parapotamal (semi-lotic) habitats. The restored sites underwent a rapid depletion of benthic coarse particulate organic matter, with direct changes in most of the investigated parameters of bottom sediments, including conductivity, total organic carbon, soluble reactive phosphorus and total nitrogen. Redundancy analysis revealed that the changes in benthic fauna structure resulted from the increased connectivity with the river (flow rate) and changes in the chemical properties of sediments. The restored oxbow lakes were colonized by six new macroinvertebrate species whose density increased substantially. The assessment of the overall river-floodplain system restoration project indicated positive implications for improving the qualitative and quantitative structure of benthic fauna. However, to confirm ecologically successful restoration, it is necessary to evaluate appropriate sets of indicators based on a complex food web structure and more efficient or enhanced ecosystem functions. This study contributes to the discussion of sustainable management of floodplains to provide benefits to macroinvertebrates as indicators of aquatic ecosystem health under different restoration activities.

Inorganic Nitrogen Compounds in Water Mains in Northern Poland and Their Implication for Health Risk

AbstractThe presence of nitrogen compounds significantly affects the quality of water intended for human consumption. The maximum contaminant level (MCL) of nitrogen in potable water in Poland was set up as follows: NO2−–0.5 and NO3––50  mg/L, NH4+–0.50  mg/L. For this reason, the objective of the study was to monitor the chemical composition of water as a priority basis for the water quality information system to provide consumers with water that meets the appropriate health and quality standards. The results of a multiyear study (1992–2003) carried out in four regions and at 12 monitoring sites in northern Poland showed NO2− and NO3− levels significantly below MCL limits. Low nitrate concentrations in water drawn from Quaternary water-bearing horizons indicate the absence of point sources of pollution. Ammonia levels exceeded MCL values at every monitoring site. Supernormal ammonia concentrations in raw water are indicative of the natural origin of ammonia ions. They are correlated with the depth of the...

The significance of oxbow lakes for the ecosystem of afforested river valleys.

The significance of oxbow lakes for the ecosystem of afforested river valleys The interest in significance of forest areas in water quality improvement has been increasing since creation of biogeochemical barriers became effective tools against the input of pollutants to surface water from diffuse sources. Along meandering river valleys, numerous floodplain lakes often appear as valuable water ecosystems but of advanced eutrophy. Their trophic status depends not only on the hydrological connectivity with the river but also land use in the direct vicinity of the reservoir. Research on water ecosystems in the postglacial river valleys in northern Poland contributed to identification of the role of woodland area in pollutants migration in the valley of the łyna River. The study on the ecosystem concerned seasonal variation in nutrient concentrations (N and P) and bottom sediments properties in relation to hydrological conditions (water level fluctuations). Based on the collected data we attempted prediction of the reservoir lifetime. Depending on hydrological, geological and topographic conditions the origin of water supply of the basin is changing. Annual water level fluctuations in the range of 200 cm cause the basin capacity variation as much as 5 times. Nevertheless, water quality in the lake was conditioned by the riverine supply, the significant share in the lake feeding has groundwater supply from hillslope aquifer and seepage through alluvial aquifer. Contribution of every origin supply depends on river flow rate and valley water level, it depends on alluvial ground formations permeability and relief. Hillslope erosion of the concave bank was responsible for high nitrogen and phosphorus outflows. The research showed that primary and secondary production and freshets contributed to intensive deposition of bottom sediments in oxbow lake. The increase rate of sediment determined on the base of matter balance was 10 times higher than deposition rate of bottom sediments in glacial lakes. The accelerated processes of silting-up and shallowing and terrestialization of the valuable ecosystems indicate the necessity of floodpain lakes protection due to ecological functions they play in forestry landscape. Znaczenie starorzeczy dla ekosystemu zalesionych dolin rzecznych Zainteresowanie funkcjα, jakα pełniα obszary leśne w poprawie jakości wody, wzrastało od kiedy bariery biogeochemiczne stały się efektywnym narzędziem przeciwko zanieczyszczeniom obszarowym, wprowadzanym do wód powierzch-niowych. Wzdłuż dolin rzek meandrujαcych pojawiajα się liczne jeziora równin zalewowych jako cenne ekosystemy wodne, lecz o zaawansowanym stopniu eutrofizacji. Ich poziom troficzny zależy nie tylko od stopnia połαczenia z rzekα, ale również od użytkowania przyległego obszaru. Badania prowadzone nad ekosystemami wodnymi rzek północnej części kraju przyczyniły się do poznania roli, jakα odgrywajα obszary zalesione w migracji zanieczyszczerń w dolinie łyny. Badania dotyczyły sezonowej zmienności koncentracji azotu i fosforu oraz właściwości osadów dennych w odniesieniu do zmiennych warunków hydrologicznych. W kontekście lokalnych warunków hydrologicznych, geologicznych i topograficznych zasilanie starorzecza ma różny charakter. Oscylacje poziomu wody w zbiorniku w cyklu rocznym w zakresie dochodzαcym do ponad 200 cm determinowała ponad 5-krotnα zmiennośc jego objętości i zdolności retencyjnej. Jednakże jakość wody w zbiorniku była uwarunkowana zasilaniem przez wody rzeki, istotny udział w zasilaniu zbiornika miały wody gruntowe zbocza doliny i wody aluwialne przesiαkajαce z koryta rzecznego. Ich udział jest zmienny w czasie i zależy bezpośrednio od wielkości przepływu w rzece i poziomu wód w dolinie, przepuszczalności utworów aluwialnych oraz rzeźby terenu. Erozja stromej skarpy brzegu wklęsłego zbiornika odpowiadała za duży spływ azotu i fosforu do jego wód. Procesami generujαcymi depozycję osadów dennych w starorzeczach były produkcja pierwotna i wtórna oraz wezbrania rzeczne. Bilans materii w zbiorniku odpowiadał za przynajmniej 10-krotnie szybszy przyrost osadów niż w jeziorach glacjalnych. Przyśpieszony proces odcinania, wypłycania i zalαdowienia cennych ekosystemów wymusza konieczność ochrony w odniesieniu do funkcji, jakie pełniα one w krajobrazie leśnym.

Patterns of phytoplankton composition in coastal lakes differed by connectivity with the Baltic Sea

The study was aimed to analyse reactions of the major groups of phytoplankton to the mixing regime of fresh and brackish waters in coastal lakes and the associated changes in physicochemical properties of lake waters. For this purpose, on the basis of data collected from 6 coastal lakes located along the southern coast of the Baltic Sea, differing in intensity of intrusion of brackish sea water: limnetic, L (2), limnetic/oligohaline, L/O (2), and oligohaline, O (2), we assessed the associations of major phytoplankton groups with environmental conditions. Statistical analyses revealed that the structure of phytoplankton groups significantly differed among three lakes types, and the variation in these variables was best explained by water temperature, total phosphorus, salinity, PO43-, transparency, dissolved oxygen, and NO3-. Relative phytoplankton biomass showed significant differences among the O-L/O-L lake types and formed the following proportion 1:2:3.5. Cyanobacteria constituted a dominant algae group in the lakes, showing the decreasing trend from 86.5% in the L to 69.3% in the O lakes. The indicator value analysis showed that all the studied lakes were dominated by algae preferring freshwater habitats, among which Cyanobacteria and Cryptophyta were indicator groups. Redundancy analysis showed that increasing salinity has got a negative effect on Cyanobacteria and Bacillariophyta biomass, and did not stimulate the development of any algal group. In the coastal lakes we observed 2 distinct stable states (limnetic and oligohaline) as well as transitional phases between them: (1) seaward drift (limnetic-oligohaline) with increasing salinity, and (2) landward drift (oligohaline-limnetic) with decreasing salinity. Algal communities showed the most distinct differences in biomass in limnetic and oligohaline states. These observations suggest that the structure and biomass of phytoplankton may respond gradually on the level of hydrological connectivity, or may respond abruptly creating two alternative stable states: limnetic and oligohaline.

Environmental controls on the abundance of methanotrophs and methanogens in peat bog lakes

The aim of the present study was to identify the factors that influence the composition of methanogens and methanotrophs in the background prokaryotic community in peat bog lakes. We hypothesized that the microbial composition is a function of the physicochemical conditions of the water and a function of depth-dependent oxygen (DO) concentrations. To address this aim, we collected water samples from subsurface and near-bottom layers, representing oxic and anoxic conditions in 4 peat bog lakes in NE Poland. The structure of methanogenic Archaea and methane-oxidizing bacteria (MOB) was determined with double labeled-fluorescence in situ hybridization (DOPE-FISH). The results showed significant differences in Procaryota communities between the oxic (subsurface) and suboxic/anoxic (near-bottom) layers in peat bog lakes (t-test, p < 0.05). The methanogens from the Archaea domain were observed in anoxic periods, while methanotrophs were present regardless of water depth and season. The abundance of methanogens was inversely correlated with DO and CO2. Methanotrophs adapted better to the changing habitat conditions. The nonmetrical multidimensional scaling (NMS) and partial least square regression (PLS-R) models showed that the methanotrophs in subsurface layers are positively associated with temperature, DOC, and TON while negatively associated with pH. The DO availability is not a prerequisite condition for the presence of methanothrophs. The most important factors for MOB at the bottom were CO2 and TON. Due to a significant role of methanotrophs in the control of the methane emission flux rates, there is a need for further research on factors responsible for methanotroph development in peat bog lakes.

Comprehensive comparison of a few variants of cluster analysis as data mining tool in supporting of environmental management

A few variants of hierarchical cluster analysis (CA) as tool of assessment of multidimensional similarity in environmental dataset are compared. The dataset consisted of analytical results of determination of metals (Na, K, Ca, Sc, Fe, Co, Zn, As, Br, Rb, Mo, Sb, Cs, Ba, La, Ce, Sm, Hf and Th) in ambient air dried and kept alive, by the means of hydroponics, moss baskets collected in 12 locations on the area of Tricity (Poland). The selected urban locations covered sites of various anthropogenic impact (cargo transit, heavy traffic, apartments, shipyard, etc.). Factor analysis in the variant of Principal Component Analysis (PCA) is offered as a validating method for CA. The results of three scaling variants are presented: column scaling, row scaling and column scaling followed by row scaling. Moreover, the results of two linkage methods with squared Euclidean distance as the similarity measure are compared: Ward’s linkage and complete linkage. The cluster significance is indicated basing on Sneath’s index. Some urban pollution profiles (fertilizer plant emission, fossil fuel burning, municipal waste dump, mineral soil dust) were identified and the possibility of their application by the environmental decision makers or managers is pointed out. The complete environmental data exploration procedure is recommended.