ACTA AGROBOTANICA Vol. 66 (1), 2013: 39–52 DOI: 10.5586/aa.2013.005 OBSERVATIONS ON AEROPHYTIC CYANOBACTERIA AND ALGAE FROM TEN CAVES IN THE OJCÓW NATIONAL PARK Joanna Czerwik-Marcinkowska Department of Botany, Institute of Biology, Jan Kochanowski University Świętokrzyska 15, 25-420 Kielce, Poland e-mail: [email protected] Received: 19.04.2012 Abstract Hašler, 2007). At the entrance of limestone caves This study, carried out in 2010–11, focuses on species and on the surfaces around electrical lights, cyanobac- composition and distribution of cyanobacterial and algal com- teria compete for light with other algae, bryophytes munities colonizing ten caves (Biała, Ciemna, Koziarnia, Kra- and ferns, but in the deepest recesses of the caves they kowska, Łokietka, Okopy Wielka Dolna, Sąspowska, Sypialnia, are usually the only phototrophs (Round, 1981). Zbójecka and Złodziejska Caves) in the Ojców National Park Most caves represent stable environments characte- (South Poland). A total of 85 taxa were identified, 35 of them rized by uniform temperatures throughout the year, belonging to cyanobacteria, 30 chlorophytes, and 20 belonging high humidity and low natural light (Hernández- to other groups of algae. Aerophytic cyanobacteria dominated -Mariné and Canals, 1994; Ducarme et al. in these calcareous habitats. Nine species, Gloeocapsa alpina, 2004; Poulič ková and Hašler, 2007; Lam- Nostoc commune, Chlorella vulgaris, Dilabifilum arthopyre- niae, Klebsormidium flaccidum, Muriella decolor, Neocystis prinou et al. 2009). According to Lamprinou et subglobosa, and Orthoseira roseana, were the most abundant al. (2012), a typical cave is described as having three taxa in all the caves. The investigated microhabitats offer re- major habitat zones based on light penetration and in- latively stable microclimatic conditions and are likely to be tensity: the entrance-, transition-, and dim light zone. responsible for the observed vertical distribution of aerophytic Moreover, cave characteristics, such as dimensions, cyanobacteria and algae. morphology, location, orientation and rocky substra- te, can play an important role for the biocommuni- Key words: algae, cyanobacteria, caves, Ojców National ty structure. All caves belong to habitats of extreme Park, Poland. conditions characterized by a low content of nutrients (Pedersen, 2000; Mulec et al. 2008). However, many groups of organisms prefer such conditions for INTRODUCTION the colonization and growth. The following occur most Caves are unique in terms of specific natural frequently in caves: liverworts, mosses, some ferns, characteristics such as: microclimate, temperature, hu- flowering plants, algae and cyanobacteria (Dobat, midity and others. According to Mulec and Kosi 1970; Kuehn et al. 1992; Sanchez et al. 2002; (2009), caves have a special place in human history and Mulec, 2005; Mulec et al. 2008; Mulec and many caves are inscribed on the United Nations Edu- Kosi, 2009). Algae often play a key role in the food cational, Scientific and Cultural Organization (UNE- webs and in the colonization processes of rocky ha- SCO) World Heritage List. Recently, many caves have bitats (sediments, rocky surfaces, artificial material) experienced intensified tourist visits and to make them as well as they produce colourful effects on the caves more attractive for visitors, artificial illumination was walls (Golubič , 1967). These processes are favo- installed which changed physico-chemical conditions ured by usually stable environmental conditions preva- in the caves. However, most caves, at least in Euro- iling in caves. All these factors make caves attractive pe, are damp and the walls at the entrance are covered for cosmopolitan species, which consequently elimi- with green algal gelatinous mass (Poulič ková and nate the native components (Pipan, 2005). Although 40 Joanna Czerwik-Marcinkowska infrequently, but new algal species have also been caves (Łokietka and Ciemna) open to tourists, samples identified in caves (Jones, 1964; Hernandéz- were also collected from around artificial light sources, -Mariné and Canals, 1994). Aerophytic algae at different distances from the source, and from sites and cyanobacteria are usually observed in cave en- of most intensive growth. Scraped material was used trances illuminated by direct or indirect sunlight and directly for observation under the light microscope. also around the artificial light in caves that are open to Two sampling zones were distinguished in each cave: tourists (Pentecost, 1992; Mulec, 2005; M u - A – light zone, comprising the entrance (usually lit lec et al. 2008; Czerwik-Marcinkowska and by sunlight and well-oxygenated); and B – dark zone Mroziń ska, 2011). comprising the chambers illuminated only by weak na- In Poland algological studies in caves have been tural daylight or artificial light. carried out by the following researchers: Starmach Collected organisms were cultured on standard (1963); Mroziń ska-Broda and Czerwik- Bristol agar medium, at 20oC under a 12/12h light/dark -Marcinkowska, (2004); Czerwik-Marcin- cycle at 3000 μEm-2 s-1 provided by 40W fluorescent kowska and Mroziń ska, (2008, 2009, 2010, tubes. For transmission electron microscopy (TEM), 2011). cells were fixed as previously described (Massalski The aim of this study was to present the spa- et al. 1995). Ultra-thin sections were cut with glass tial distribution of aerophytic algae and cyanobacte- knives on a Reichert-Jung ultramicrotome. Observa- ria growing in ten caves in the Ojców National Park tions and photographs were made with a TESLA BS differing in location, morphology and environmental 500 electron microscope. Cells for TEM were double conditions as part of an extensive study of caves in the fixed with glutaraldehyde in phosphate buffer and po- Polish Jura. stosmicated with osmium tetroxide in the same buffer, then they were dehydrated in series of alcohols, embed- STUDY AREA ded in the synthetic epoxy resin “SPURR” and poly- merized at 70oC for 18 h. For scanning electron micro- The caves are one of the most characteristic scopy (SEM), the samples were treated with 36% HCl, elements of the Ojców National Park and its surro- washed several times with distilled water and boiled in undings. The presence of caves in this area has been concentrated H2O2 with KClO3 in order to remove or- noticed for a long time (Chardez and Delhez, ganic matter. Cyanobacteria and algae were identified 1981; Szelerewicz and Górny, 1986; Bisek according to: Anagnostidis and Komárek et al. 1992; Gradziń ski et al. 1995a, b, 1996, (1988); Brown and Bold (1964); Brown and 1998, 2007; Gradziń ski and Szelerewicz, Lean (1969); Etll and Gärtner (1988, 1995); 2004; Górny and Szelerewicz, 2008). These Hoffmann (1986, 2002); Komárek and Ana- caves were created by underground waters dissolving gnostidis (1986, 1989); Krammer and Lan- Jurassic marine limestones (Michalik and Party- ge-Bertalot (1986, 1991). k a , 1992). Some of the caves exceed 300 m in depth. Ten caves: Biała, Ciemna, Koziarnia, Krakowska, Ło- RESULTS kietka, Okopy Wielka Dolna, Sąspowska, Sypialnia, Zbójecka and Złodziejska Caves, were studied in the A total of 85 aerophytic algae and cyanobacte- Park (Fig. 1; Table 1). The most attractive caves from ria species were identified in the ten caves in the Oj- the natural and environmental point of view, having ców National Park (Fig. 2; Table 2). Overall, cyano- corridors longer than 50 m, include the following: Bia- bacteria were dominant and represented by 35 species ła, Ciemna, Koziarnia, Krakowska, Łokietka, Okopy (40% of the total), green algae 30 species (32.7%), and Wielka Dolna, Sąspowska and Zbójecka Caves (Par- 12 diatoms species (27.2%). The frequently encoun- tyka, 1997). Only the Łokietka and Ciemna Caves tered species among cyanobacteria were as follows: (among the studied ones) are open to tourists. Aphanocapsa parietina Näg., Calothrix fusca (Kutz.) Born. & Flah., Chroococcus tenax (Kirchn.) Hierony- MATERIALS AND METHODS mus and Nostoc commune Vauch. ex Born. & Flah. They occurred both in the light (A) and dark (B) zo- Samples for algological analysis were taken nes of the studied caves. Microscopic observations from the ten caves of the Ojców National Park in the revealed that cyanobacteria are arranged in patina as- spring, summer and autumn of 2010 and 2011. Algal semblages which are blue, brown, green, or gray, and crusts were scraped from the walls and ceiling, using are arranged mosaic-like inside the caves. Among the a scalpel, into labelled plastic bags and analysed under cyanobacteria present, the following were dominant a light microscope (Jenamed 2) or inoculated for cultu- only in the caves open for tourism, i.e. the Łokietka ring on agar plates (Figs 4–6). Additionally, in the two Cave and the Ciemna Cave: Gloeocapsa alpina (Näg.) Observations on aerophytic cyanobacteria and algae from ten caves in the Ojców National Park 41 F. Brand, Nodularia harveyana Thuret ex Born. & zone). There were also species found only in the pla- Flah. and Tolypothrix epilithica Näg. The most rare ces within direct sunlight: Chroococcus cf. ercegovi- green algae species were: Bracteococcus minor (Cho- cii Kom. & Anagn., Chlorogloea novacekii Kom. & dat) Petrová (Fig. 3), Desmococcus olivaceum (Pers. Montejano, Plectonema cf. puteale (Kirchn.) Hansg., ex Arch.) Laudon, Muriella decolor Vischer, Scotiel- Characium strictum A. Braun, Desmococcus oliva- lopsis terrestris (Reisigl) Punčochářová & Kalina and ceum (Pers. ex Arch.) Laudon and Keriochlamys styria-