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Diatom assemblages as indicators of salinity gradients : a case study from a coastal lake

Rzodkiewicz M., Gąbka M., Szpikowska G., Woszczyk M.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 3

325--339

EN

In order to understand the variability of diatoms in coastal lakes and its relationship to salinity, the authors have conducted a two-year study at Lake Resko Przymorskie (the Southern Baltic coast), which has a salinity between 1.9-4.8 PSU. Redundancy analysis (RDA) was used to describe the relationship between the species composition and selected variables. Four of the 10 measured variables of surface water chemistry (Cl- and PO43- concentrations, temperature, and pH) significantly explained 23% of the variation in the diatom species composition. We found 82 taxa of diatoms (mostly tychoplanktonic) and determined the optimum and tolerance levels of salinity for predominant taxa (49 species with minimum 2% abundance). The optimum chloride concentration for the predominant diatoms ranged from 1471 to 2961 mg Cl- l-1. The most abundant brackish water species was Pseudostaurosiropsis geocollegarum. Brackish-freshwater diatoms were represented by Cyclotella atomus, Cyclotella meneghiniana, Diatoma tenuis and Staurosira subsalina. The most abundant fresh-brackish water diatoms were Amphora pediculus, Fragilaria sopotensis, Hippodonta hungarica, Pseudostaurosira brevistriata and Staurosira construens. Freshwater taxa accounted for as little as 1% of the population. This study provides new data on the ecology of coastal lakes and the possibility of using diatom-based transfer functions in the reconstruction of past environmental changes.

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Significance of current velocity gradients for distribution patterns of charophytes versus mosses and vascular plant communities in a lowland stream

Jakubas E., Gąbka M.

Oceanological and Hydrobiological Studies

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2015

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Vol. 44, No. 2

139--150

EN

The study focused on the relationships between charophytes and the surrounding species composition and environmental factors in a lowland stream (Flinta stream, Western Poland). A total of 32 vegetation plots (4 m × 4 m) and 13 environmental variables were tested. Detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) were used to describe the relationships between the species composition and the selected variables. Dominance curves of aquatic plants, response curves (GAMs model) of charophytes and other macrophytes to the velocity gradient (the most important environmental factor, the Monte Carlo test) were prepared. In this study, 2 species of charophytes were recorded: Chara vulgaris and Chara globularis and 5 other co-occurring macroscopic algae, 2 mosses and 10 vascular plants. In the studied stream, charophytes occupied the separate niche. Chara vulgaris stands with moss vegetation were found in stream sections with the highest velocity of the water current (0.29 m s-1 mean), and the Chara globularis (with dominant Potamogeton species), preferred sections with the smallest water current velocity (0.19 m s-1 mean). Charophytes seem to respond to ecological gradients differently from mosses and vascular plants. These differences are related to current velocity, pH, conductivity and organic matter in bottom sediments, and to the niche differentiation associated with them.

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Factors determining the distribution of rheophil and protected Hildenbrandia rivularis (Liebman) J. Agardh 1851, the Rhodophyta freshwater species in lowland ecosystems

Jakubas E., Gąbka M., Joniak T.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

679--693

EN

The relationships of Hildenbrandia rivularis (Rhodophyta), the species composition of its surroundings detailed environmental variables (water chemistry and hydrological, morphological and bottom features) in a lowland river (Wełna river, Western Poland) was investigated. H. rivularis from 40 stands was tested together with 25 environmental variables and vegetation. Detrended correspondence analysis (DCA) and redundancy analysis (RDA) were used to describe the relations between the species composition and the selected variables. The uniqueness of this protected species is an ability of formation incrustation on rocks but also coexistence with two groups of species: other algae and vascular plants. In study twenty-two plant taxa were recorded in 40 vegetation plots, including 4 macroscopic algae, 2 mosses and 16 vascular plants. The most common H. rivularis co-occurred with Leptodictyum riparium, Fontinalis antipyretica and Nuphar lutea. Most of the studied plots with red algae were characterised by shallow water and strong water velocity. H. rivularis prefers alkaline water with high conductivity. The results of the RDA, after forward selection, demonstrated that pH gradient, optical features such as dissolved organic matter and water colour – control the variation in the floristic communities with H. rivularis.

4

Pulsed Arc Welding Applied to Robotized Joining of Thin Car-Body Steel Sheets

Piwowarczyk T., Korzeniowski M., Kustroń P., Gąbka M.

Advances in Materials Science

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2013

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Vol. 13, nr 3(37)

49--63

EN

The paper presents the potential of robotized welding applied for thin steel sheets using variable parameters of arc (different welding programs: Standard, Pulse, Twin Pulse, and Speed Pulse). Trial welded joints were made for sheets 0.8 to 1.25 mm thick and relevant welding parameters were selected for them during the first stage of examinations. The properties of welded joints were determined with non-destructive and destructive testing. In turn, visual inspection allowed to evaluate the shape and dimensional conformities of joints and to detect superficial imperfections. In order to improve detection accuracy, penetration testing was used for confirmation purposes. Tensile strength testing was also made to determine mechanical properties of the weld and the heat-affected zone. Metallographic examinations were used for sheets of all thickness values and for all welding programs to verify that the structure of joints was correct. All examinations and tests made on trial joints enabled to find how pulsing arc welding affects quality and strength properties of welds as compared with standard method.

5

The influence of co-occurring vegetation and habitat variables on distribution of rare charophyte species lychnothamnus barbatus (Meyen) in lakes of Western Poland

Gąbka M., Burchardt L., Owsianny P.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

13-25

EN

At present Lychnothamnus barbatus (Meyen) Leonhardi belongs to the rarest species of charophytes in the world. In Europe it is classified as threatened with extinction. The problem of extinction of this species is intriguing, in particular in the context of its widespread occurrence in Europe and Asia till the last decade of the 20th century. Records of L. barbatus from Wielkopolska region (Western Poland) are know from 15 lakes. The most of them was stated in 19th and on beginning of 20th centuries. Now, this species is growing in 6 lakes, from among 2 sites are new. This study was undertaken to a) determine the abundance of L. barbatus and the co-occurring plant species at different sites in lakes, b) determine the most important ecological parameters controlling the structure communities with L. barbatus co-occurring and quantitative responses of this species. In 7 lakes (area 5.5-197 ha, depth max. 7.8-38 m, trophic state: meso-eutrophic) in western Poland the species composition and coverage of vegetation were studied at the 23 plots with L. barbatus occurrence in relation to the measured variables. Seventeen environmental parameters were measured including: depth of water, pH, conductivity, SO[4^2-], NH[4^+], NO[^3-], PO[4^3-], Na[^+], K[^+], Ca[^2+], Mg[^2+], chlorophyll a, Secchi disc visibility, colour, O[2] dissolved, saturation, total Fe during the period July-September. The DCA and CCA analyses were used to assess the relation between vegetation parameters and environmental variables. L. barbatus preferred the water rich in Ca[^+], Mg[^2+] and SO[4^2-] and with high concentrations of nutrients, especially NH[4^+] and PO[4^3-], and moderate values of electrolytic conductivity. In the studied lakes, L. barbatus occupied the separate niche. This species formed the communities in very shallow marginal zones of lakes (0.4-1.5 m) with other macrophytes like: Chara vulgaris, C. tomentosa, Potamogeton nitens, and monospecific stands on margins of steep lake slopes (4-6 m) with Chara globularis fo. hedwigii and Nitella mucronata. The process of extinction of this species seems to be related with increasing turbidity related in turn to algal blooming in lakes and with the spatial competition of vascular macrophytes, especially Ceratophyllum demersum.

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Species composition of testate amoebae (Protists) and environmental parameters in a Sphagnum peatland

Lamentowicz Ł., Gąbka M., Lamentowicz M.

Polish Journal of Ecology

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2007

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Vol. 55, nr 4

749-759

EN

The research was made on the largest (ca 500 ha) peatland complex in the western Poland ("Chlebowo" mire) (N 52[degrees] 44'14.3" E 16[degrees]45'20.7"), that exists under considerable anthropogenic pressure. Species composition of testate amoebae in selected microhabitats was described. The fundamental environmental factors influencing the structure of assemblages were determined. Twenty four samples were taken from 10 sites (Sphagnum lawn, hollow and hummock) dominated by Sphagnum and brown mosses. Each of them was analysed in relation to its taxonomical composition. Nine environmental parameters (acidity (pH), conductivity colour, NH4[^+], NO3[^-], PO4[^3-], SO4[^2-], Ca[^2+] and [Mg[^2]) were measured in the field and laboratory. Thirty two testate amoebae species of 13 genera were identified within the 24 sites. In most of the sites species composition was dominated by Hyalosphenia papilio Leidy, Cyclopyxis arcelloides Leidy and Hyalosphenia elegans Leidy, however the most numerous were Amphitrema flavum Archer, Hyalosphenia papilio Leidy and Cyclopyxis arcelloides Leidy. The particular parameters, i.e. pH, depth to the water table (DWT) and So4[^2-] content significantly explained the species variability. Multivariate analyses showed that species tend to group especially along the pH gradient; to a smaller extent along the DWT and SO 4[^2-], together with pH.

7

Symulacja procesów obróbkowych w środowisku naturalnym

Iżykowski S., Gąbka M., Górski P.

Mechanik

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2007

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R. 80, nr 11

960-961

PL

Przedstawiono proces tworzenia wirtualnego środowiska wytwarzania w systemie NCSIMUL. Opisano metodykę postępowania prowadzącą do budowy wirtualnej obrabiarki, dla której przeprowadzono symulację obróbki wielogniazdowej formy obrotowej. Dokonanie optymalizacji tego procesu i analiz wymiarowych produktu w środowisku wirtualnym umożliwiło pozytywne wdrożenie jego obróbki na maszynie rzeczywistej.

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Badania symulacyjne procesów obróbkowych w środowisku wirtualnym

Iżykowski S., Gąbka M., Surmiński P.

Górnictwo Odkrywkowe

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2006

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R. 48, nr 5-6

151-154

PL

Przedstawiono proces tworzenia wirtualnego środowiska wytwarzania w systemie NCSIMUL. Opisano metodykę postępowania prowadzącą do budowy wirtualnej obrabiarki, dla której przeprowadzono symulację obróbki wielogniazdowej formy obrotowej. Dokonanie optymalizacji tego procesu i analiz wymiarowych produktu w środowisku wirtualnym umożliwiło pozytywne wdrożenie jego obróbki na maszynie rzeczywistej.

EN

The paper introduces a process of creating a virtual environment of production in the NCSIMUL system. Described is a methodology leading to the creation of a virtual CVC machine tool, on which machining of a rotary, multi-cavity mould was simulated. Optimization of such process and dimensional analysis of the product in the virtual environment allowed for successful implementing the machining process on a real machine tool.

9

Zagadnienia klasyfikacji taksonomicznej i syntaksonomii ramienic (characeae) i ich zbiorowisk

Gąbka M., Pełechaty M.

Ekologia i Technika

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2006

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R. 14, nr 3

87-92

PL

Celem niniejszej pracy było przedstawienie podejść w klasyfikacji taksonomicznej ramienic na bazie przeglądu literatury. Przedyskutowano problem klasyfikacji i zagadnienień taksonomicznych ramienic, wynikający ze znacznego zróżnicowania morfologicznego oraz konsekwencji przebiegu procesów reprodukcyjnych i odrębności molekularnej.

EN

The aim of the paper was to present main historical and up-to-date concepts in the taxonomy of the family Characeae. Based on the literature data, two complementary approaches are presented: concerning charophyte morphology supplemented with different life histories and current molecular achievements. The present state of Polish charophyte flora is also discussed. Concerning charophyte vegetation, the authors present reviewed syntaxonomical system of Polish charophyte meadows, regarding 30 associations belonging to 5 alliances within the class Charetea fragilis.

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Występowanie ramienic (characeae, charophyta) w drobnych zbiornikach wodnych Wielkopolski

Gąbka M.

Ekologia i Technika

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2006

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R. 14, nr 3

114-117

PL

W pracy przedstawiono informacje o występowaniu ramienic w drobnych ekosystemach wodnych Wielkopolski takich jak zbiorniki astatyczne, torfianki, glinianki, jeziora zaawansowane w procesie zarastania, torfowiska węglanowe i strefy szuwarowe wokół jezior.

EN

The paper presents synthetically information about occurrences of stoneworts in small water reservoirs of the Wielkopolska region on the basis of herbarium materials, literature of the subject and own research conducted in the 2000-2005. The water ecosystems e.g. peat-pits, gravel pits, calcareous peat-bogs, clay pits, shallow lakes and artificial pools are most important habitat for stoneworts in this region. In small water reservoirs, 19 species of Characeae, among 34 known in Poland, were noticed. The most frequent representatives of Characeae were in hollow peat and calcareous peat-bog. Many of the charophyta, which were observed, are regarded as endangered and vulnerable in Poland. The list comprises species such as Chara tenuispina, C. polyacantha, C. crassicaulis, Nitella tenuissima, N. syncarpa and N. capillaris. In the examined water ecosystems 9 protected species were found: Nitella syncarpa, N. gracillis, N. capillaris, N. opaca, N. tenuissima, Chara polyacantha, C. braunii C. crassicaulis and C. tenuispina.

11

Środowiskotwórcza rola ramienic

Pełechaty M., Gąbka M.

Ekologia i Technika

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2006

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R. 14, nr 3

93-97

PL

Celem artykułu był przegląd danych literaturowych dotyczących pośrednich i bezpośrednich mechanizmów, dzięki którym ramienicom przypisuje się środowiskową rolę w ekosystemie wodnym. Jak wynika z przedstawionego przeglądu znaczenie makrofitów wodnych, w tym ramienic, w sieci zależności wewnątrzekosystemalnych jest ogólnie przyjęte w przypadku jezior płytkich. Konieczne są jednak dalsze badania, zwłaszcza dotyczące allelopatii in situ.

EN

The aim of the paper was to review the literature data on the direct and indirect influences of charophytes on planktonic algae and cyanoprokaryots. Possible mechanisms are presented regarding the charophyte-related shifts in habitat conditions as well as allelopathic interplay between charophytes and phytoplankton. Main concepts and, also, some controversies are discussed and illustrated with the results of the authors in situ-studies. Due to up-to-date literature the importance of macrophytes, including charophytes, is commonly agreed upon, particularly for shallow lakes. However, further studies, concerning allelopathy in situ, are required.

12

Rzadkie i zagrożone ramienice (characeae, charophyta) oraz ich ostoje w Wielkopolsce

Gąbka M.

Ekologia i Technika

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2006

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R. 14, nr 3

107-110

PL

W Wielkopolsce - terenie bogatym w różne typy genetyczno-morfologiczne ekosystemów wodnych stwierdzono w sumie występowanie 24 gatunków ramienic. Stwierdzono również zmniejszenie liczby stanowisk ramienic związanych z jeziorami. Należy jednak zaznaczyć, że obecnie ważnym miejscem występowania tych makroglonów są drobne zbiorniki wodne o zróżnicowanym statusie troficznym, często o charakterze antropogenicznym.

EN

The aim of the paper was to present the floristic diversity of charophytes (Characeae family) of the Wielkopolska region on the basis of herbarium materials, literature of the subject and own research conducted in the years 2000-2005. This region is rich in lakes and small freshwater reservoirs, which differ from each other in morphometric parameters, trophy, development in the processes of succession and anthropopressure. In water reservoirs and on wetland areas 24 species of charophytes, among 34 known in Poland, were noticed. Analysis of frequency shows high percentage of very rare (1-5 localities) and abundant ( over 60 localities) species. Chara globularis, C. tomentosa i C. hispida was the most frequent representative of Characeae in water reservoirs of the Wielkopolska region. Among 24 species which, were observed in this area, 11 are rare in the region (e.g. Chara rudis, C. filiformis, Nitella flexilis, N. capillaris, N. syncarpa) or in Poland (e.g. Chara tenuispina, C. crassicaulis, Nitella tenuissima, Tolypella glomerata). In the examined area 12 protected species of charophytes were found.