Cyanophytes on limestone rocks in the Szopczański Gorge ( Pieniny Mountains ) – their ecomorphology and ultrastructure

The Szopczański Gorge of the Pieniny Mountains area is an interesting and unique environment. In limestone habitats, some cyanophytes and algae were typically much more abundant than others. Very few detailed studies of limestone epilithic cyanophytes have been carried out in the Gorges of the Pieniny Mountains with the exception of observations made in the last 50 years in many habitats of the Pieniny Mountains that indicate a rich and diversified epilithic phycoflora [1-3]. The mostly published data are from the Dunajec River and other water biotopes in the Pieniny Mountains by Chudyba [4], Kawecka [5], Wasylik [6], Tarnowska [7], Starmach [1], Mrozińska-Webb [8], Mrozińska [9-12], Kawecka and Szczęsny [13], Kawecka and Mrozińska [14], Sanecki [15], Sanecki and Bucka [16], Sanecki et al. [17], Kawecka and Sanecki [18], Mrozińska and Czerwik-Marcinkowska [19], Mrozińska et al. [20,21], Czerwik-Marcinkowska and Mrozińska [22], Wróbel and Zarzycki [23], Wilk-Woźniak et al. [24].


Study area
The Pieniny Mountains consist mainly of limestone and dolomite rock strata with the most picturesque Three Crowns (alt.982 m) and Sokolica (alt.747 m) mountains covered by fir, beech, spruce and pine forests.Steep cliffs surrounded by rocky crags rise up to 300 m above the Dunajec River.The most famous gorges of the Pieniny Mountains are the Dunajec River Gorge in Pieniny National Park and Homole Gorge.In addition, there are many swamps, springs and torrents in the Pieniny range which are a very characteristic and important elements of this landscape.
The algological study presented here focused on cyanophytes dwelling on the limestones in the area of Szopczański Gorge (Fig. 1).This Gorge is situated between the western slopes of Three Crowns and the eastern slopes of Podskalnia Mountain in the Pieniny National Park.

Material and methods
The fieldwork was carried out in the years 2006-2008.The sampling procedure was as follows.Generally, for each observation, a method of visual inspection was used by which detectable places hosting cyanophytes in the form of black, brown, grey-green growths/crusts were scraped using a scalpel.This material was collected into small plastic bags and used directly for observation under a light microscope (JE-NAMED 2).Parts of each sample were used for a cultivation on agar plates in the laboratory.Cultures of cyanophytes were incubated in the standard Bristol agar medium [25] at a temperature of 20 o C and in a diurnal regime (12/12 h light/dark cycle, 3000 μEm -2 s -1 , 40 W cool fluorescent tubes).The cultivations were examined every 12 days for an isolation of some cyanophyte species to obtain pure cultures [26].For transmission electron microscopy (TEM) cells were fixed as previously described [27].Ultra-thin sections were prepared in a way described by Reynolds [28].TEM was made by a TESLA BS 500 electron microscope.The general taxonomic literature and specific publications, which were used for identification of cyanophyte species, were following: Starmach [29], Anagnostidis and Komárek [30], Komárek and Anagnostidis [31], Whitton [32].
Using morphological and ultrastructural analyses, we were able to recognize five taxa of cyanophytes occurring on limestone rocks.The first research carried out by Starmach [1] in the rocky Szopczański Gorge has revealed a particularly interesting phycoflora from the ecological points of view (Tab.1).We have confirmed the occurrence of five characteristic epilithic taxa of cyanophytes, but many species reported earlier were not detected.Starmach [1] and Mrozińska [11,12] enumerate, in addition to those described in our study, also Calothrix parietina (growing on limestone rocks), Chroococcus kutzingianum, Ch. minutus, Gloeocapsa alpine, Homoeothrix nordstedtii, Schizothrix lardacea, S. rubra and Tholypothrix byssoidea (found on rocky cliffs covered with slime).It is known that some epilithic species of cyanophytes inhabit also the limestone rocks of the Tatras and Ojców [33].Rock-surfaces contaminated by mud have recently been observed in Szopczański Gorge.This, together with geological, morphological and climatic changes undoubtedly affected algal and cyanophytic diversity in this area.Only after further studies are carried out on cyanophytes in Szopczański Gorge, it will be possible to compare them with the respective phycoflora of other mountain gorges.valuable comments on the manuscript from prof.dr hab.Beata Zagórska-Marek (Dept. of Plant Morphology and Development, University of Wrocław).We thank mgr inż.Krystyna Świeca (Dept. of Botany, University of Jan Kochanowski) for technical assistance with TEM.Additional funding was provided by the Funding of Ministry of Education of Czech Republic, project No. MSM0021622416.

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The Author(s) 2011 Published by Polish Botanical Society Czerwik-Marcinkowska and Uher / Ultrastructure of Cyanophyta from limestone rocks

Fig. 3 a
Fig. 3 a Longitudinal ultra-thin section of Tolypothrix distorta var.penicilatum (Thuret) Lemmerman, showing the peripheral arrangement of thylakoids and cell inclusions: polyhedral bodies or carboxysomes and vacuoles.b-d Pseudanabaea catenata Lauterborn.b Longitudinal and transverse section showing a number and an arrangement of thylakoids and cell inclusions: vacuoles, polyhedral bodies or carboxysomes.c Two vegetative cells.d Transverse section of the vegetative cell with thin wall.PH -polyhedral bodies; T -thylakoids; V -vacuoles.Scale bar -1 µm.

Fig. 4
Fig. 4 Longitudinal ultra-thin sections of Phormidium favosum (Bory) Gomont.a A part of a filament with terminal cell.b Cells of two parallel filaments with clearly visible thylakoids and polyhedral bodies.c Thylakoid morphology.PH -polyhedral bodies; T -thylakoids.Scale bar -1 μm.