Preslia 84: 427–504, 2012 427 Vegetation of the Czech Republic: diversity, ecology, history and dynamics Vegetace České republiky: diverzita, ekologie, historie a dynamika Dedicated to the centenary of the Czech Botanical Society (1912–2012) Milan C h y t r ý Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-611 37 Brno, Czech Republic, e-mail: [email protected] Chytrý M. (2012): Vegetation of the Czech Republic: diversity, ecology, history and dynamics. – Preslia 84: 427–504. This review summarizes basic information on the diversity of vegetation in the Czech Republic. It describes basic environmenal factors affecting vegetation, vegetation history since the last glacial, biomes occurring in the Czech Republic (zonal biomes of broad-leaved deciduous forest and forest- steppe, and azonal biomes of taiga and tundra), altitudinal zonation of vegetation and landscapes with an exceptionally high diversity of vegetation types (deep river valleys in the Bohemian Massif, karst areas, sandstone pseudokarst areas, solitary volcanic hills, glacial cirques, lowland riverine landscapes and serpentine areas). Vegetation types, delimited according to the monograph Vegeta- tion of the Czech Republic, are described with emphasis on their diversity, ecology, history and dynamics. K e y w o r d s: alpine, aquatic, central Europe, forest, grassland, phytosociology, plant communi- ties, ruderal, vegetation change, vegetation classification, vegetation history, weed, wetland Introduction The Czech Republic is a land-locked country in central Europe occupying an area of 78,867 km2. It is situated in the zone of temperate broad-leaved deciduous forest, which in the south-east borders on the forest-steppe zone. Its current vegetation is affected by abiotic conditions such as geology, soil and climate, historical biogeographical processes and human activity. This paper provides a review of the diversity of Czech vegetation. Previous reviews were published in Czech as introductory chapters to major national botanical monographs (Neuhäusl 1988, Neuhäuslová et al. 1998b, Sádlo 2007), but there is no comprehensive review in another language. Specific information on individual vegetation types is summarized in recent phytosociological overviews, in particular four volumes of the unfinished series Vegetation survey of the Czech Republic, which focused on forest vegetation (Moravec 1998, Moravec et al. 2000, Husová et al. 2002, Neuhäuslová 2003), in the monograph Vegetation of the Czech Republic (Chytrý 2007, 2009, 2011; www.sci.muni.cz/botany/vegsci/vegetace.php) and Habitat catalogue of the Czech Republic (Chytrý et al. 2010b). Czech vegetation was mapped as reconstructed natural vegetation at a scale 1 : 200,000 (Mikyška et al. 1968–1972), potential natural vegetation at 1 : 500,000 (map: Neuhäuslová et al. 1997; Czech explanatory text: Neuhäuslová et al. 1998a; English explanatory text: Neuhäuslová et al. 2001) and actual vegetation as part of 428 Preslia 84: 427–504, 2012 habitat mapping at 1 : 10,000 (Härtel et al. 2009, Chytrý et al. 2010b; mapy.nature.cz). Brief regional accounts of major vegetation types within biogeographical regions of the Czech Republic are provided by Culek (1996). History of the research on vegetation in the Czech Republic is summarized by Krahulec (2012). The taxonomy and nomenclature of species in this paper follow Danihelka et al. (2012) and Kučera et al. (2012). Abiotic factors Altitudinal range of the Czech Republic is 115–1602 m a.s.l. (Fig. 1). There are two major geological units in the country (Chlupáč et al. 2011): the Bohemian Massif in the western and central part (Bohemia and western and north-western Moravia) and Western Carpathians in the eastern part (eastern and southern Moravia). The Bohemian Massif is an old mountain system created by Variscan (Hercynian) orogeny in the Late Palaeozoic and is formed mainly of igneous and metamorphic rocks of pre-Permian age such as gran- ite, granodiorite, gneiss and schist, which in places are covered by younger sedimentary or volcanic rocks (Fig. 2). In the Cretaceous the northern half of Bohemia was flooded by a marine transgression. Cretaceous sediments, occurring mainly in the lowlands of north- ern, central and eastern Bohemia, include two bedrock types: (i) acidic siliceous sand- stones, which locally form sandstone pseudokarst with deep gorges and rock towers (Fig. 3), and (ii) calcareous claystones and marlstones. Cretaceous freshwater sediments occur in two large basins in southern Bohemia: Českobudějovická Basin and Třeboňská Basin. By the Tertiary the Bohemian Massif had been weathered to a gently undulating peneplain, but during the Alpine orogeny in the Tertiary it was broken into smaller tectonic units, some of which were elevated, forming mountain ranges especially along what are now the national borders with Austria, Germany and Poland. The highest of these mountain ranges are the Sudetes along the Czech-Polish border, consisting of several more or less isolated mountain groups, most notably the Krkonoše (Giant Mts; 1602 m), Králický Sněžník (1424 m) and Hrubý Jeseník (1492 m). Other prominent mountain ranges are the Krušné Mts (Ore Mts; 1244 m) on the border with Saxony and the Šumava (Bohemian Forest; 1456 m) on the border with Bavaria and Upper Austria. In the Pleistocene local glaciers developed on the highest mountain ranges, forming cirques, some with lakes. However, flat or gently undulating terrain was preserved in large areas of these mountain ranges. In other areas of the Bohemian Massif, most notably those in the southern foothills of the Krušné Mts, large land masses sank during the Alpine orogeny to form basins, which were subsequently filled with Upper Tertiary sediments. Alpine orogeny also caused volcanic activity in the north-western and northern part of the Bohemian Massif, which gave rise to a large area of basalt bedrock in the Doupovské Mts and a number of isolated volcanic hills in the České středohoří Mts, which are formed of both base-rich (e.g. basalt) and acidic (e.g. phonolite) rocks. Since the Upper Tertiary v-shaped river valleys deeply cut in hard, poorly weathering rocks of the Bohemian Massif, forming landscapes of high geodiversity with a broad variety of contrasting vegetation types (e.g. the Vltava, Otava, Lužnice, Berounka, Sázava, Dyje and Jihlava valleys; Fig. 4). Western Carpathians are separated from the Bohemian Massif by broad elongated depressions, running in a SW–NE direction across Moravia, which are filled with Upper Tertiary and Quaternary sediments. The Czech part of the Western Carpathians is formed Chytrý: Vegetation of the Czech Republic 429 Fig. 1. – Basic topographic map and historical lands of the Czech Republic. See Appendix 1 for a guide to Czech toponyms. All the maps in this paper were prepared by O. Hájek. Fig. 2. – Simplified geological map of the Czech Republic (based on the digital geological map 1 : 500,000 – GEOČR500 by Czech Geological Survey 1998). 430 Preslia 84: 427–504, 2012 Fig. 3. – Areas of sandstone pseudokarst (based on topographic maps 1 : 50,000) and sand deposits (based on interpretation of the soil map of the Czech Republic provided by Czech University of Life Sciences to the Czech National Geoportal at http://geoportal.cenia.cz). (1) Labské pískovce, (2) Hradčanské Cliffs, (3) Kokořín region, (4) Český ráj, (5) Broumov region, (6) Toulovcovy Maštale site. Fig. 4. – Deep river valleys, defined as areas with elevation range larger than 60 m within 300 m on both sides of the river. Chytrý: Vegetation of the Czech Republic 431 of flysch, a bedrock type composed of alternating layers of water-permeable sandstone and impervious claystone of Cretaceous to Lower Tertiary age. These rocks are rather soft and prone to erosion, forming landscapes with broad valleys and gentle slopes. Flysch sed- iments can be both calcareous (especially in the southern Moravian lowlands and upland fringes) and acidic (especially in the Moravian-Silesian Beskids of north-eastern Moravia). Flysch landscapes are rich in springs and small-scale landslides, and on the cal- careous sediments there is a combination of calcareous and relatively wet soils, which is otherwise rare in the Czech Republic. The highest part of the Carpathians in the Czech Republic is the Moravian-Silesian Beskids, which reach an altitude of 1424 m. Acidic bedrock with cambisol, and less frequently, podzol soils prevails throughout the Czech Republic, especially in the submontane and montane areas of the Bohemian Massif, but also in some lowland areas. Therefore, local occurrences of limestone or other calcare- ous rocks (Fig. 5) markedly increase local diversity of flora and vegetation. Areas of poorly weathering, hard limestone of Silurian, Devonian or Jurassic age, with well-developed karst features and rendzina soils occur especially in the Bohemian Karst of central Bohemia, and Moravian Karst and the Pavlovské Hills of southern Moravia. Small patches of metamorphic limestone (marble), occurring in association with siliceous metamorphic rocks, are found especially in south-western Bohemia (Šumava foothills), north-eastern Bohemia and west- ern Moravia. Other calcareous rocks include soft sedimentary limestone, calcareous claystone and marl of Cretaceous to Tertiary age, which occur mainly in the lowlands of northern, central and eastern Bohemia and broad valleys and adjacent hilly landscapes fring- ing the Carpathians. Many areas below 300 m a.s.l. (or below 400 m in the driest regions) are covered by loess,