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EN
Charophytes are a group of green algae that grow in various types of water ecosystems and are characterized by a high degree of plasticity and morphological variation. To analyze the genetic diversity and taxonomic rank of several species from the genus Chara, the fingerprinting technique of Amplified Fragment Length Polymorphism (AFLP) was applied. We studied species that belong to sect. Grovesia (C. tenuispina, C. globularis, C. virgata, C. aspera and C. strigosa) and two species from the sect. Hartmania (C. intermedia and C. hispida). The individuals were collected in the field in north-eastern, central and eastern Poland. The species were identified based on morphological features and then analyzed using the AFLP fingerprinting method. UPGMA clustering and PCA analysis as well as morphological analysis revealed a clear separation of C. tenuispina and C. globularis, which formed separate clusters supported by high bootstrap values. Therefore, these species were distinguish as separate taxa, rather than varieties of C. globularis. Similarly, C. virgata also formed a separate cluster, thereby confirming that this taxon is a separate species, rather than a variety of C. globularis. The AFLP analysis did not show any differentiation between C. aspera and C. strigosa. The presented results do not fully support the taxonomic interpretation for the existence of several polymorphic species with numerous variations and forms, however, in some examples, the distinctive nature of the reproduction system may be used as a distinguishing feature of the taxa.
PL
W artykule przedstawiono wyniki badań rozmieszczenia ramienic, prowadzonych w różnych regionach kraju w latach 2010–2012. Szczegółowo przedstawiono warunki siedliskowe 52 stanowisk, na których występowało 15 gatunków z rodzajów: Chara (12), Nitella (2) i Nitellopsis (1). W analizowanej grupie stanowisk najczęściej notowano Chara vulgaris, Ch. contraria, Ch. globularis i Ch. virgata. W trakcie badań odnaleziono liczne stanowiska gatunków zagrożonych wymarciem w Polsce, takich jak: Ch. aspera, Ch. filiformis, Ch. hispida, Ch. intermedia, Ch. polyacantha, Ch. rudis i Nitella mucronata. Gatunkiem uznawanym za zanikły w kraju jest odnaleziona Ch. connivens. Ramienice zasiedlały głównie wody płytkie i bardzo płytkie (młaki, torfowiska, potorfia, przybrzeżne strefy akwenów), choć w niektórych rozległych zalanych piaskowniach i kamieniołomach występowały także na znacznych głębokościach (do 8,7 m). Ramienice występowały także na obszarach monitorowanych użytków rolnych, objętych programem rolnośrodowiskowym (Chara vulgaris, Ch. globularis, Ch. virgata, Ch. tomentosa, Ch. hispida). W takich miejscach najczęściej występowała Ch. vulgaris var. longibracteata. Na uwagę zasługuje stwierdzenie zdecydowanej większości stanowisk ramienic poza jeziorami polodowcowymi, w Polsce uznawanymi za ich główne siedlisko. Większość danych z Wyżyny Śląsko-Krakowskiej z lat 2010–2012 omówiono w osobnych pracach, niemniej wykorzystano je w zestawieniach, analizach i wnioskach niniejszej pracy, obejmujących łącznie 22 gatunki na 108 stanowiskach (230 notowań).
EN
The paper is a compilation of stonewort records made during the field surveys in various regions of Poland in the years 2010–2012. We present in detail habitat conditions of 52 sites with 15 charophytes representing 3 genera: Chara (12 species), Nitella (2) and Nitellopsis (1). Among them, there are some of the rarest Polish charophytes like Chara connivens considered extinct in Poland and endangered species like: Ch. aspera, Ch. filiformis, Ch. hispida, Ch. intermedia, Ch. polyacantha, Ch. rudis and Nitella mucronata. Chara vulgaris, Ch. contraria, Ch. globularis and Ch. virgata have been the most frequently found species. Numerous records of charophytes outside glacial lakes (in Poland commonly regarded as the main habitat of stoneworts) are particularly noteworthy. Stoneworts were recorded mostly in shallow and very shallow waters. However, in some deep sand- and stone pits they occurred to a depth of 8.7 m. Surprisingly, charophytes were also found in rural landscape areas included in agri-environment schemes (Ch. vulgaris, Ch. globularis, Ch. hispida, Ch. tomentosa, Ch. virgata). The most often recorded species in such habitats was Chara vulgaris var. longibracteata. Chara vulgaris was also the most frequently recorded species in all types of habitats, confirming its wide ecological amplitude and distribution. Most data of Silesia-Cracow Upland of 2010–2012 were published in detail separately, however, we used them in summaries, analysis and conclusions, which cover a total of 22 species in 108 sites (230 records).
EN
The subject of this work is a comparative analysis of stonewort populations in 5 lobelia lakes of the Kashubian Lakeland based on literature data from the mid-1970s and the authors' own studies from 2006. In the 1970s 15 sites of 7 stonewort species: Chara delicatula, C. fragilis, C. tomentosa, C. rudis, Nitella flexilis, N. opaca and N. mucronata were recorded in the lakes under study. The populations of C. delicatula and N. flexilis occupied the area from 0.3 to 6 m deep and were characterized by 20% cover on average. Thirty years later, in 2006, the presence of only 6 out of 15 stands was confirmed: 3 of C. delicatula and 3 of N. flexilis. Thus, a total of 9 stands (60%) and 5 species (71%) had disappeared completely. The majority of the preserved populations survived in a vestigial form. Population areas of C. delicatula reached a depth of 2 m and their cover did not exceed 5%. Populations of N. flexilis occupied the littoral up to a depth of 7 m and had 10% cover. The disappearance of stoneworts was probably caused by both anthropogenic factors and natural processes.
EN
The results of investigations performed in Lake Wielkowiejskie showed the influence of macrophyte architecture, understood as plant density, on the structure of plankton communities as well as the habitat preferences of particular species in both seasonal and spatial aspects.
5
Content available remote Manganese accumulation by two species of Chara
EN
This paper reports the results of Mn accumulation in two species of green algae: Chara globularis and Chara hispida. The results of laboratory and field experiments show a rapid accumulation of Mn by charophytes and demonstrate that deposit formation on the plant surface in the so-called adsorption phase occurs in Mn accumulation. Both species can be an important factor in Mn circulation in lakes.
EN
The examination of the composition and dynamics of periphytic communities took place in three lakes of similar morphometry . Lake Wielkowiejskie, Budzyńskie and Dębiniec, situated in the Wielkopolska region, (Western Poland). These lakes are typical macrophyte-dominated, shallow and polymictic water bodies. Periphyton was collected from two macrophyte-covered stations, including the rush vegetation station (Typha angustifolia L.) and the stonewort stand (Chara tomentosa L.) in each examined lake. The material was sampled three times in 2003, including the spring (April), summer (July) and autumn (September) seasons, from the same parts of the lakes.The aim of the study was to find out whether there is an influence of particular macrophyte species, differing spatially and morphologically and representing two different ecological types of aquatic vegetation, on the development of particular periphytic species. There was also an attempt at answering the question of what is more important in the structuring of the periphytic communities - the specific architecture of the macrophyte substratum or the physical-chemical features of a particular lake? The concentrations of chlorophyll a, TN, TP and TOC in water were higher in the Chara beds compared with theTypha stations in most cases. The Shannon-Weaver biodiversity index of periphytic algae revealed very high values in all lakes and amounted in the Typha and Chara stands to the mean values 4.68 and 3.87 respectively in Wielkowiejskie Lake, 3.32 and 4.39 in Budzyńskie Lake and 3.08 and 3.91 in Dębiniec Lake. Furthermore, the standardized index of evenness exhibited the greatest differentiation in the Typha station with the highest (0.76) in Wielkowiejskie and the lowest (0.52) in Dębiniec Lake The analysis of the growth-forms of periphytic communities showed slightly higher diversity of slowly moving and stalked diatoms in most cases at the Chara stations of all studied lakes. The similarity between periphytic communities in the Typha and Chara stands of the examined lakes, compared using the Ward method and Euclidean distance measure, revealed a stronger relationship within a particular habitat but not a lake. The clearest pattern of similarity grouping a particular habitat was obtained for the summer period, when macrophytes reached their optimum. The Jaccard similarity index confirmed the differentiation of both examined habitats, reaching the mean value of 0.34. Based on the biomass of single periphytic species, habitat selectivity for seven species was found. Significantly higher biomass was obtained in the case of the rush zone for only one algae species - Eunotia lunaris (Ehr.) Grun. In the Chara bed six species revealed significantly higher biomasses - Cosmarium regnelli Wille, Oocystis marssonii Lemm., Ulotrix zonata (Weber et Moor) Kutz., Scenedesmus acuminatus (Lagerh.) Chod., Merismopedia elegans A. Braun and Phacus orbicularis Hubner. The habitat preference of periphytic communities to different macrophyte species may be due to the environmental factors, including the specific architecture of a particular macrophyte substrate such as density or texture of the plant surface. Furthermore, seasonality, as well as physical-chemical parameters may structure periphytic communities within the littoral zone of lakes.
EN
The aim of this examination was to study the impact of the physical parameters, understood as spatial and morphological features, of two macrophyte habitats created by Chara tomentosa and Typha angustifolia on the Rotifera and Crustacea communities of three shallow lakes with extensive macrophyte cover. There were 161 zooplankton species in total identified from three lakes, with over 60% of species common among all lakes. Species richness varied between the sampling stations, with lowest values within the open water zone and highest among macrophyte stands. Significant differences in zooplankton densities between particular stations for all groups of zooplankton were observed, with the highest values within the most diverse and complex habitat – the Chara bed. Furthermore, the distribution of pelagic species between particular stations differed significantly in the case of copepods, with the highest abundance also in the stonewort beds.
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