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EN
Although well represented in the fossil diatom flora throughout Europe and Asia, from the early-middle Miocene to the Quaternary, Stauroneis balatonis is considered a very rare diatom with a contemporary distribution limited to two ancient lakes – Ohrid and Prespa. The objective of this study was to describe the first finding of S. balatonis in Serbia in Lake Savsko and to update information on the distribution and ecology of this rare species. Periphyton samples were collected from artificial substrates incubated at three depths (0.5 m, 0.8 m and 1.4 m) in Lake Savsko and the epilithic community was sampled in the littoral zone. Samples were collected weekly in summer 2014, from mid-July to mid-September. Diatom permanent slides were prepared and small numbers of S. balatonis specimens were observed only in samples collected in September from artificial substrates incubated at the greatest depth (1.4 m). Our results significantly contribute to the information on the contemporary distribution and the ecology of this rare diatom taxon, especially considering the fact that S. balatonis specimens were observed in our study in diatom communities developed on artificial substrates and in an urban reservoir, i.e. Lake Savsko.
EN
We present the first report and description of the pinnate diatom Haslea sp. from the northeastern Adriatic Sea, Croatia, producing a blue pigment. This organism is very similar to the well-known Haslea ostrearia, the first described “blue” diatom producing marennine, i.e. the pigment involved in the greening of oysters, and recently described H. provincialis. However, the Croatian diatom slightly differs from other Haslea species in its morphology and 18S rRNA sequence. The discovery of Haslea sp. from Croatia confirmed the possible existence of more species among the representatives of blue Haslea species, as previously assumed. The discovery of several genetically distinct populations of Haslea ostrearia, new species H. karadagensis, H. provincialis and Haslea sp. from Croatia, suggests that species richness in the group of “blue” diatoms is probably underestimated and still more new blue diatoms remain undiscovered. This also raises questions about previously published reports and observations of Haslea distribution in the Mediterranean Sea whether these organisms really belong to H. ostrearia.
PL
Określono możliwości stosowania okrzemek jako bionawozu nowej generacji w uprawie wierzby wiciowej w warunkach zredukowanego nawożenia syntetycznego i sprawdzono potencjał użyźniania roślin poprzez dolistną aplikację Navicula sp. Wpływ bionawożenia zależał od poziomu wzbogacenia gleby w nutrienty zawarte w syntetycznym nawozie. Pozytywny wpływ okrzemek na wzrost roślin (wysokość, liczba pędów, suma ich długości, plon świeżej i suchej biomasy) był związany ze wzrostem aktywności fizjologicznej (transpiracji, fotosyntezy, przewodnictwa szparkowego, stabilności cytomembran, zawartości chlorofilu w liściach), a także aktywności enzymatycznej (fosfatazy kwaśnej i alkalicznej, RNaz oraz dehydrogenaz). Dolistna aplikacja okrzemek zwiększyła zawartość makroelementów w biomasie roślin wierzby (N, P, K) i nie wpłynęła ujemnie na wartości parametrów energetycznych (ciepło spalania w stanie analitycznym, wartość opałowa w stanie roboczym i zawartość popiołu w stanie roboczym). Okrzemki, jako nowy bionawóz w uprawie wierzby energetycznej, umożliwiają zmniejszenie stosowanych dawek nawozów sztucznych.
EN
Willow plants (Salix viminalis L.) were fertilized with a com. synthetic fertilizer (up to 1.0 g/plant) and then with watersuspended diatoms (Navicula sp.) (600 000 cells in 1 mL of water, sonification at 20 Hz for 15 min, foliar application). The use of diatoms resulted in an increase in the quantity of microelements in plants (N, P, K) but did not affect their energetic properties (heat of combustion, calorific value and ash content) in the working state. The diatoms showed perspective potential as a new generation biofertilizer in prodn. of energy willow.
EN
Peat bogs are unique and important habitats for biodiversity at the species and ecosystem level where low pH of water plays a major role. The main objective of the present study was to compare the benthic diatom assemblage structure of the selected part of the Fenn’s and Whixall Mosses complex in order to verify whether selected sampling sites differ from each other. The complex is a cut-over, lowland raised mire, which is a National Nature Reserve (NNR) and a Site of Special Scientific Interest (SSSI). Altogether 92 diatom species were identified in 72 benthic samples collected between September 2008 and August 2009 from six selected sampling sites. Statistical cluster analysis was used to classify diatom samples and to observe the structure of diatom assemblages. The results of this analysis grouped the data set into 3 clusters with 24 samples from each of the two sampling sites in one cluster. Such a clear division shows that pH of water has an impact on the species composition, the richness and diversity of benthic diatom assemblages.
EN
Diatoma polonica, a species first observed in samples from the Western Carpathians river systems in southern Poland, is described as a species new to science. The new species status resulted from the fact that the dimensions of cells found did not fit any of the diagnoses given in the literature for the European Diatoma taxa established so far. The genus is rather species-poor, even when the entire Holarctic flora is taken into account. The new species is morphologically closest to Diatoma moniliformis Kützing, particularly with respect to the vague resemblance of the valve outlines and the presence of a rimportula in each valve pole. Further, more or less similar taxa are D. tenuis Agardh, D. problematica Lange-Bertalot and D. mesodon (Ehrenberg) Kützing, all distinguished, in addition to other specific characteristics, by the rimoportulae regularly present at only one valve pole. Characteristics of D. polonica are described and compared with those of other species based on light and scanning electron microscopy.
EN
The main aim of this study was to assess the usefulness of the Biological Diatom Index (BDI) (Lenoir & Coste 1996) for the estimation of water quality in the central section of the Pilica River, located in central Poland in Łódź province. The BDI has never been used before to monitor Polish surface waters. An analysis of the correlations between the values of the BDI and selected physico-chemical parameters was performed, as was an assessment of water quality using the BDI. On the basis of value ranges proposed by Descy and Ector (1996), a good ecological status in the Pilica River was obtained, but this did not correspond with the results achieved from the physico-chemical analysis. This study proposes new value ranges for the BDI. With these new values, the ecological state of the Pilica River changed from good to moderate, which corresponded with the physico-chemical analysis of the water. The new, proposed value ranges for the BDI assess more precisely the quality of water in lowland Polish rivers.
EN
As a result of the research carried out in Lakes Duszatyńskie and the Olchowaty stream, a new European site with Geissleria declivis (Hust.) Lange-Bert. was found — a new species for Poland. The highest abundance of G. declivis has been observed on sandy substrate and small stones in the littoral zone of the Upper Lake during the spring season. The species occurred together with Achnanthidium minutissimum (Kütz.) Czarn. var. minutissimum, A. catenatum (Bily & Marvan), Fragilaria leptostauron (Ehrenb.) Hust. var. leptostauron and F. pinnata Ehrenb. var. pinnata. Our observations revealed that G. declivis develops in lentic water bodies with medium organic matter content and neutral pH. The species seems to prefer mesotrophic waters with low to medium electrolyte content and oligosaprobous. The species morphology and identity is documented in a series of light microscopic (LM) images and for the first time under a scanning electron microscope (SEM).
EN
Research on soil diatoms has been conducted in Podkarpacie voivodeship in Dąbrowa village ( 50°03'31 N 21°48'35 E) in the Subcarpathian Province in SE Poland. On the same soil type, i.e. silty clay loam (sand 0-23%, silt >40, clay 36-50%), two tillage systems were applied under maize (Zea mays): traditional and reduced. The major aim of the research was to analyse diatom diversity depending on the applied tillage system under maize (Zea mays). In the soil samples it was identified 62 taxa of diatoms, including 38 under traditional tillage, and 50 under reduced tillage. Under traditional tillage the most frequent species were Stauroneis thermicola, Mayamaea cf. atomus var. permitis, Nitzschia palea, and Pinnularia obscura. Under reduced tillage, Amphora montana was the most abundant. The dominant diatoms are characteristic of water reservoirs but are regulary found also on wet or moist sites.
PL
Badania nad okrzemkami glebowymi prowadzono na terenie woj. Podkarpackiego w miejscowości Dąbrowa ( 50°03'31 N 21°48'35 E), gdzie na tej samej glebie zastosowano dwa systemy uprawy roli tradycyjny i uproszczony. Celem pracy było zbadanie różnorodności okrzemek w zależności od zastosowanego systemu uprawy roli na tej samej glebie - pyle ilastym (płi) pod uprawą kukurydzy. W materiale oznaczono 62 taksony okrzemek, w tym w próbkach z uprawy tradycyjnej - 38, natomiast z uprawy uproszczonej - 50 taksonów. Na polu z uprawą tradycyjną dominowały: Stauroneis thermicola, Mayamaea cf. atomus var. permitis, Nitzschia palea i Pinnularia obscura, natomiast na polu z uprawą uproszczoną najliczniej rozwijała się Amphora montana. W obydwóch systemach uprawy dominowały okrzemki występujące głównie w zbiornikach wodnych, ale także regularnie na mokrych i wilgotnych miejscach.
EN
Due to anthropogenic stress, the character of the Rąbień peat-bog reserve is changing, and large parts of it are being transformed into a transitional peat-bog. During more than 23 years of research, considerable changes have been noted in water pH (from 4.63 to 6.64), trophic status, and the species composition of algae. The subject of the research carried out in 2004-2005 were Bacillariophyceae and Chlorophyta. A decrease was observed in the number of species characteristic of high peat-bogs in favor of alkaliphilic species and those occurring in eutrophic waters.
EN
This paper focuses on the diatom flora of Moss Creek in Antarctica that was collected during two summer (1995/96 and 2001/02) seasons. Of the 95 taxa identified in Moss Creek, two groups of diatom communities were distinguished. Achnanthes germainii, Eucocconeis ninckei, and Nitzschia homburgiensis, taxa indicative of unpolluted waters, dominated in the upper course of the creek. The other group was found in the lower reaches of the creek and included taxa indicative of eutrophic environments. In this part of the creek Mayamaea atomus associated with Nitzschia gracilis and Planothidium lanceolatum were dominant. In both sampling periods the species composition of the dominant taxa was similar with the distinct predomination of Mayamaea atomus. During the 1995/96 season, Nitzschia gracilis, N. homburgiensis, and Planothidium lanceolatum also occurred abundantly, whereas in 2001/02 the proportions of Nitzschia gracilis and Planothidium lanceolatum showed a slight increase.
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