NOVITATES BOTANICAE UNIVERSITATIS CAROLINAE 19/2008: 19–21

2.3 Species composition of in biological soil crusts on natural substrata

ONDŘEJ PEKSA

INTRODUCTION Th e specimens of lichenized fungi have been studied using routine lichenological methods. For determination Lichens play an important role in soil-crust communi- of collected specimens, the works of Coppins (1987), Giralt ties. As autotrophic organisms, they participate markedly et al. (1993), Purvis et al. (1992), Tønsberg (1992), Wirth in carbon fi xation, and cyanolichens also show N-fi xation (1995), and other taxonomic publications have been used. activity (Belnap 2001). /moss crust obstructs a fast Th e nomenclature of lichens follows Santesson et al. (2004) water runoff by roughening soil surfaces. Subterranean or respective works included in references. All investigated structures of lichens (hyphae, rhizinae) contribute consider- specimens have been deposited in the PL. ably to soil stability and resistance to wind and water erosion (Warren 2001). Both phycolichens and cyanolichens with diff erent thal- RESULTS AND DISCUSSION lus types occur in soil crusts (crustose, foliose, fruticose) including special forms of arid regions like Fensterfl echten In all localities, well-developed biological soil crusts with (window lichen) (Belnap et al. 2001). In total, 13 cyano- distinct participation of lichens were observed. Moreover, lichen and 69 phycolichen genera are reported from soil there occur some areas with dominance of terricolous li- crusts of the Earth. Th e proportion of lichens in the crusts is chens in each of the localities (open sites with naked soil higher on substrates with more carbonate, gypsum and silt and low competion of vascular plants). A total of 46 taxa of content than on poor soils (Büdel 2001). terricolous lichens were recorded during the recent fl oristic Lichens occur in biological soil crusts of diff erent geo- approach (summarized in Table 2.3.1). Th e major part of graphical areas and vegetation types. Within the European the records belongs to the genera (30) and Pla- temperate region, specifi c soil-lichen communities can be cynthiella (4). Th e most frequent species occurring in all found in xerothermic steppe formations, coastal as well of localities are Cladonia coccifera, C. furcata, C. macilenta, as inland dunes, on open soil in heaths and very oft en on C. pyxidata and Placynthiella icmalea, which represent the less or more extensive, oft en anthropogenic, disturbed common species of acidic substrates in open habitats (naked areas (sand-pits, quarries, roadsides, etc.; Büdel 2001). In the soil, humus, rotted wood). Several records are considered Czech Republic, biological soil crusts with a predominance to be an uncommon or rare species to the Czech Republic, of lichens occur except antropogenic substrata, mainly in e.g., Cladonia incrassata, C. polycarpoides, C. portentosa and natural habitats of sandstone regions or isolated inland C. subcervicornis. dunes and in steppe formations of warm regions. Th e highest diversity (33 species) of terricolous lichens Th is chapter describes terricolous lichens of biolo- was detected in sandstone rocks and gorges of the Nature gical soil crusts founded in three (semi)natural habitats: Reserve Babylon, probably due to the highest variety of mi- Střezovská rokle gorge, the margin of airport in Ralsko and crohabitats and good natural state of the locality. Nature Reserve Babylon in Bohemian Switzerland. Babylon Nature Reserve is characterized with presence of climatically very diff erent MATERIAL AND METHODS habitats: deep cold humid gorges and dry plateaus of sandstone rocks covered by relic pine forests. Due to this microclimatic Th is chapter contains the results of a fl oristic study per- diversity together with the climatic conditions of Bohemian formed in the period 2005–2007 in selected localities: the Switzerland as whole, some species with diff erent ecological Nature Monument Střezovská rokle, the former military requirements (sub-Atlantic, mountain) grow in this area. Ralsko airport and the Nature Reserve Babylon in Bohemi- Th e locality is characterized by high number of recorded an Switzerland National Park (see chapter 2.1). For complete terricolous lichens (33), especially Cladonia species (23 com- results of the fl oristic approach of Babylon Nature Reserve pared with 13 and 14 in other two localities) including see Svoboda et al. (2006). Only terricolous lichens associated rare species Cladonia incrassata, C. portentosa and C. sub- with biological soil crusts are included. cervicornis. Mainly on the plateaus, oft en near the rims of

19 ONDŘEJ PEKSA

Table 2.3.1 The list of recorded lichen species. 1 – the Ba- sandstone rocks with relatively thin humus layer and low bylon Nature Reserve (* Palice et al. 2002, and Svoboda et participation of vascular plants, species rich community of al. 2006), 2 – airport in Ralsko, 3 – Střezovská rokle gorge. terricolous lichens is developed (see Colour plates, Fig. 2.3.1). It is composed mostly of crustose lichens from the genera Taxon 123Placynthiella and Trapeliopsis and fruticose “Cladonias” head- rufus ++ ed by “reindeer lichens” Cladonia arbuscula, C. portentosa, Cetraria aculeata +++C. rangi ferina and other species like C. gracilis and C. uncialis. Cetraria islandica + Sandy slopes as well as rotting wood in humid gorges Cladonia arbuscula ssp. arbuscula ++ might be covered by crust lichens adapted to the lack of light like and ericetorum as well as Cladonia arbuscula ssp. mitis + much less conspicuous Trapeliopsis glaucolepidea. Due to the Cladonia cervicornis ++ specifi c character of sandstone (high porosity, etc.), these Cladonia ciliata + primary terricolous species can also oft en grow directly on Cladonia coccifera +++rocks, especially weathered and moist. Cladonia coniocraea ++ Cladonia cornuta ++ Th e former military airport Ralsko represents “semi-natural” habitat – initially probably Cladonia deformis ++ bare and open (grassy) area not far from the runway is re- Cladonia digitata + cently colonized by pines, birches, etc. Biological soil crusts Cladonia fi mbriata ++with predominance of terricolous lichens are well developed Cladonia foliacea + especially in the heather moor – on naked sandy soil among Cladonia furcata +++the heather shrubs with minimal participation of other Cladonia glauca * vascular plants (see Colour plates, Fig. 2.3.2). Th e composi- Cladonia gracilis ++ tion of the local lichen community is similar to that of open sites of Babylon (except the rare species!) due to similar Cladonia chlorophaea ++ substrate – sandy soil. Several species of Cladonia (C. coc- Cladonia incrassata + cifera, C. furcata, C. macilenta, C. pyxidata and C. subulata) Cladonia macilenta +++together with Cetraria aculeata and crustose lichens from Cladonia ochrochlora + the genus Placynthiella predominate in the biological soil Cladonia polycarpoides + crust. Some Cladonia species (predominantly squamules of Cladonia polydactyla + Cladonia pyxidata) are oft en infected by lichenicolous fun- Cladonia portentosa + gus Arthrorhaphis aeruginosa, which evokes an atypical deep bluegreen colouration of the thallus. Naked soil, mosses and Cladonia pyxidata +++ lichens, are oft en covered by inconspicious apothecia and Cladonia ramulosa ++goniocysts of Vezdaea acicularis observable especially dur- Cladonia rangiferina + ing wet periods of the year. Cladonia rangiformis + Cladonia rei ++Střezovská rokle Nature Monument Cladonia squamosa + diff ers from other two localities mainly by the presence of species typical for sunny habitats with more alkalic sub- Cladonia subcervicornis *+ strates, e.g., Cladonia foliacea (see Colour plates, Fig. 2.3.3), Cladonia subulata ++C. polycarpoides and C. rangiformis. Th e mentioned species Cladonia uncialis + are bound to the small grassy plateaous on the ridges and Cladonia verticillata + upper parts of the steep slopes of erosion cones, together baeomyces + with other dominants as Cetraria aculeata, Cladonia mitis Icmadophila ericetorum + and C. subu lata (see Colour plates, Fig. 2.3.4). In shaded Peltigera didactyla + humid sites at the bases of slopes, ephemeral microscopic lichens like Steinia geophana and Th elidium zwackhii can Placynthiella dasaea ++ be found. Small rests of heat stands are occupied mainly by Placynthiella icmalea +++pioneer lichens like Dibaeis baeomyces, Cladonia coccifera, Placynthiella oligotropha *+ + C. coniocraea, C. macilenta, C. pyxidata and Trapelia coarc- Placynthiella uliginosa ++ tata (the last species grows here except the small pebbles also Steinia geophana + directly on naked soil). Thelidium zwackhii + Trapelia coarctata + Noteworthy lichen species Trapeliopsis glaucolepidea + Cladonia incrassata Trapeliopsis granulosa ++ Suza (1938) calls C. incrassata a characteristic “peat- Vezdaea acicularis + lichen”, solely due to it’s ecological relationship to the peat

20 2.3 SPECIES COMPOSITION OF LICHENS IN BIOLOGICAL SOIL CRUSTS ON NATURAL SUBSTRATA bogs (pine-forest bogs) of the Bohemian massif. Litterski of C. subcervicornis (Litterski & Ahti 2004), the region of & Ahti (2004) described it as a holarctic oceanic species with Bohemian Switzerland represent very isolated and inland a disjuncted distribution pattern, occuring in Europe espe- locality of the species. cially on peaty soil in bogs. In the locality of Babylon, this red-fruited species with small podetia was collected at the base of an old pine in a relic pine forest on sandstone rock. CONCLUSIONS In the same habitat, its typical companions C. macilenta, C. deformis and Trapeliopsis granulosa were also recorded. Terricolous lichens of biological soil crusts were studied in the three natural or seminatural localities in the North Bo- Cladonia polycarpoides hemia. A total of 46 taxa of terricolous lichens were recorded Conspicious species typical for sun-exposed habitats during the recent fl oristic approach. Th e highest diversity with more alkalic sandy or stony soils mainly in xerotherm of lichens was detected in the Nature Reserve Babylon in regions (steppes), oft en growing together with Cladonia Bohemian Switzerland, probably due to the highest variety foliacea (Kovář 1912; Suza 1947; Wirth 1995). Th e rests of of microhabitats and good natural state of the locality. steppe vegetation in the locality of Střezovská rokle ravine Th e major part of the lichen records belongs to the gene- represent a typical habitat of the species. ra Cladonia (30) and Placynthiella (4). Th e most frequent species occuring in all of localities (Cladonia coccifera, Cladonia subcervicornis C. furcata, C. macilenta, C. pyxidata, Placynthiella icmalea) Rare species with the centre of distribution in the Atlan- represent common “pioneer lichens” typical for acidic sub- tic fl oristic province (Litterski & Ahti 2004). In the Babylon strates in open habitats (oft en disturbed). Several records Nature Reserve was fi rstly recorded in 2002 – commented belong to rare species of well–preserved plant communities together with other species with similar ecology (Clado- (Cladonia incrassata, C. portentosa, C. subcervicornis – Ba- nia glauca, C. portentosa) in Palice et al. (2002) and Palice bylon, C. polycarpoides – Střezovská rokle). et al. (2007). Compared with recently known distribution

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