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The Department of Geobotany has completed and is running research on vegetation diversity and dynamics at various temporal and spatial scales using several approaches:
Cooperation with branch-related groups is carried out in the Biodiversity Research Centre where attention is paid to the accessibility of distribution databases of vascular plants. The Czech Bioplatform communicates with researchers dealing with biodiversity and, together with policy-makers and stakeholders, makes recommendations on strategic documents on biodiversity policy.
The current research of the Department of Geobotany on the Korean peninsula is based on the scientific collaboration with the College of Natural Science, Andong University, South Korea. Previous work provided experience in the areas of spatial and species structure, dendroecology, and regeneration patterns especially for temperate deciduous broad-leaved forests dominated by Quercus mongolica in several mountainous areas of the continental part of the Korean Peninsula. The next intended step is to study these forest communities in mountainous island conditions on the southern coast of the Korean Peninsula, for example, on Mt. Halla (Cheju Island).
Between 2005 and 2007, we established fifty 20 × 20 m permanent plots along altitudinal and latitudinal gradients in forests of South Korea. The plots were the first permanent plots established in Mt. Halla along elevation gradients ranging from 950 to 1780 m. Data obtained from these plots will be used to:
The research is carried out in cooperation with the Department of Functional Ecology, Institute of Botany, Třeboň. The research is supported by Academy of Sciences of the Czech Republic and Korean Science and Engeneering Foundation (KOSEF) (project nr. M200050902, Vegetation structure and dynamics along elevation gradient in forested landscapes of South Korea).
The rocky savanna in southeastern Brazil is locally known as campos rupestres, a peculiar vegetation type bound to a mosaic of quartzite outcrops and shallow white sands occurring mostly above 1000m altitudes in southeastern and northeastern Brazil. This vegetation provides a unique opportunity to investigate high beta-diversity and many narrowly endemic species. Furthermore vicarious species in several typical families and genera occur on almost every campo rupestre mountaintop. Physiognomically, these plant communities are very similar, but the assemblages of actual species are so distinct that each mountaintop may be described as a different vegetation unit. However, the presence of numerous, more widespread floristic savanna elements should provide a solid basis to describe higher-ranking syntaxa, potentially useful within a broader classification system of Neotropical savannas. Approximately 1,000 vegetation samples (relevés) representing 40,000 species occurrences and 6,000 herbarium specimens from seven main localities were obtained with the help of over eighty taxonomists from many countries.
This project represents unprecedented Czech-Brazilian cooperation in vegetation research (together with Prof R. J. V. Alves, Rio de Janeiro) and is meant to synthesize the remaining available vegetation data, describing the remaining plant units of the campos rupestres studied in the southern part of the Espinhaço Chain.
The most substantial outcomes of this project include: a) description of vegetation structure within stands on outcrops, on derived litholic soils and in epiphytic merocoenoses; b) consolidation of a preliminary classification framework of Brazilian rocky savannas; c) detection of phytogeographic links among Neotropical savannas. Another result of this work is the expected completion of a checklist of campo rupestre plant taxa and life strategy of endemic plant species of campo rupestre sites from the São José mountain range, with over 1000 vascular plant species (currently being edited).
Species-rich forests are currently the focus of conservation management because of maintaining their biodiversity. Intensive grazing and browsing of ungulates considerably changes the structure and survival of herb assemblages in ancient forests that represent an important segment within European cultural landscapes.
Large herbivores may influence biodiversity in both positive and negative ways depending on the forest. Vegetation development in dependence on game impact was studied in three pairs of fenced and unfenced plots in oak-hornbeam, dry oak and beech forests every year since 1993. In all enclosures, there was significant tree and shrub rejuvenation in comparison to the unfenced area, where this process was blocked due to the high number of game. In all enclosures, the beta diversity decreased and vegetation homogenized. The most pronounced changes occurred in the oak-hornbeam enclosure, where the shrub layer strongly developed and the herb layer sharply declined. In unfenced plots in thermophilous oak and beech forests, the development of invasive and other nitrophilous species were supported by game. Game can maintain oak-hornbeam and dry oak forest stands open and support light-demanding, often rare plant species. Thus, game population control should be considered based on the environment and goals of nature conservation.
The research is carried out in cooperation with the Administration of the Křivoklátsko Landscape Protected Area and Biosphere Reserve (www. krivoklatsko.nature.cz) and ZO ČSOP Brejl.
The research object is the structure of vegetation studied at broad scale including e.g. occurrence of species populations, species combinations, plant communities, complex ecosystems and large vegetation mosaics. The fundamental frame of the research is landscape (ca 1000 km2 – Dokesko study region) and Holocene period (ca 10,000 years with detailed study of recent stage).
The general aim is to recognize the contribution of the relict survival of vegetation to the development of European cultural landscape. A special aim is to analyze and explain historical roots of vegetation diversity in the Dokesko region. The relationships among following concepts, data source and interpretative approaches are studied:
The key problem is the relationship between relictness and landscape changes. Two extreme developmental scenarios of the Holocene landscape are possible. The first one is characterized by maximalisation of historical changes, with significant role being played by local invasions and extinctions, continuous anthropogenic disturbances and great differences in local histories. This scenario determined the development in the adjacent old settlement area of the Elbe / Jizera lowlands, and it probably affected the marginal parts of the study region. The second scenario is based on vegetation stability and relict survival in a stable environment. In accordance to existing biogeographic and palaebotanical outcomes, we consider that the bulk of the study area is probably of high conservative character and the local vegetation is related to the early Holocene ecosystem of taiga.
The research is supported by the Grant Agency of Academy of Sciences of the Czech Republic (GAAVČR IAAX00050801) in cooperation with the Institute of Archaeology of the Academy of Sciences of the Czech Republic (www.arup.cas.cz) and the Department of Botany, Faculty of Sciences, Charles University, Prague (http://botany.natur.cuni.cz).
Palaeoecological research with respect to climatic, hydrologic and vegetation changes focuses on chrono-biostratigraphy of sedimentary series and on palaeo-reconstructions of the Late Glacial and Holocene of the last 15 thousand years.
Vegetation development records from raised bogs, fens, and lacustrine sediments investigated palynologically with high-resolution determination of palynomorphs are the main subjects of research. Mainly the Department of Geobotany does palynological investigations with research focusing on the Bohemia to High Sudeten (Krkonoše/Giant Mts) on the north of CR, to the Bohemian Forest (Šumava Mts) on the south, and on Moravia to southern Moravia and the Dyje River valleys (GAAVČR IAAX00130801).
Palynological analysis of the mountain-raised bogs of the Bohemian Forest (Grant project GAAVČR A6005603) provides information on the mountain forest development and migration of climax trees. In the High Sudeten the palynological research focuses on the development of arcto-alpine tundra and on periglacial events of the extensive mires of cryovegetation habitats.
Under the European Pollen Monitoring Programme (INQUA) 40 pollen traps in the Czech Republic are being collected and replaced yearly to gain a more detailed understanding of pollen accumulation.
Palynological analyses of secular sequences of the Pleistocene maars of Praclaux and Ribains (Massive Central, France) were carried out in bilateral collaboration between the Czech Academy of Sciences and the Centre national de la recherche scientifique (www.cnrs.fr).
Palaeoecology is also being simultaneously addressed in the Department of Ecology in Brno.
