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The influence of extremal climatic phenomena at the recultivated and succession areas in Třeboňsko Protected Landscapa Area
NEMEŠKALOVÁ, Pavla
PLA Třeboňsko is located in the southeastern part of South Bohemia, and has an area of 700 km {$^2$}. It is an extraordinary region, where preserved valuable natural assets, but also many hundreds of years of human transformation of the cultural landscape. Basic river basin axis Třeboňsko are Třeboňsko Lužnice river in the floodplain which are 14 lakes created after gravel extraction. Coast lakes were part of forestry artificially reclaimed, partly remained left natural succession. Extreme weather events (floods, snow and strong wind calamity) in 2002, 2005, 2007 have different effects on the current status of coastal vegetation rehabilitated, compared with a similar old natural secondary succession.
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Algae and cyanobacteria colonizing toxic soils on coal-mining dumps
HRČKOVÁ, Kristýna
Species composition of soil algal and cyanobacterial communities was investigated in thirteen sites of different toxicity of spoil material on dumps in the Sokolov mining area (Czech Republic). The adaptation ability of various algal and cyanobacterial species to live in toxic environment and the effect of different amendments (wooden coal, organic matter, dolomitic limestone) of toxic soils were tested both in laboratory and field experiments. According to results, species composition corresponded to environmental characteristic (pH, conductivity, substrate type). Some green unicellular algae grew successfully in extracts from the most toxic substrate and seemed to be well adapted to low pH conditions. Results indicate that increase of pH is a basic precondition for the establishment of more diverse and abundant algal flora in highly acidic sites.
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Evaluation of vegetation remnants of former settlements in selected border areas
KALNÁ, Eva
Eva Kalná, 2010:Evaluation of vegetation remnants of former settlements in selected border areas. It was chosen region Zhůří for this work, which is one of the displaced villages at Šumava Mountains, which was part of the Dobrá Voda military training area. First, the work is devoted to the history of the village and then to changes in vegetation both directly and indirectly influenced by humans. The part of theme of this paper is primarily exploring areas of interest in terms of plant species, providing evidence of former settlements and making photographs and map outputs for each species found. The next theme is the evaluate of using the area from 1949 to the present, which over decades has fundamentally changed. Work also focuses on comparisons between the state of use from the 1949 today state habitat.
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Spontaneous succession of vegetation of abandoned quarries in the Bohemian Karst: Occurrence of species in quarries and their surroundings
KAREŠOVÁ, Petra
Variation of vegetation during spontanneous succession was researched in ten limestone quarries in the Bohemian Karst in central part of the Czech Republic. Five abandoned quarries surrounded by woodland and five quarries with grassland prevailing in the surroundings were chosen. The age of quarries varied from 33 to 97 years. The complete list of plant species was recorded for each quarry and near surroundings (up to 100m).Resulting analyses demonstrated the close relationship between the occurrence of species in the quarries and their surroundings. The quarries may act as refugia for rare and retreating specie
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A spontaneous succession in young abandoned fields
VÍTOVCOVÁ, Kamila
Initial stages of spontaneous succession were studied in two differently aged abandoned field. The main tasks were to answer the following questions: Are the differences in vegetation related to the distance to a source of diaspores? Which species exhibit easier dispersal from the source? The souce of diaspors have a significant effect on the vegetation in the abandoned field and thus on the process of spontaneous succession. The succession leads to meadow vegetation and the succession is rather fast.
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An experimental study of initial succession on different substrata: analysis of changes in plant species cover and some soil biological parameters and their relationships
KRESÁČ, Martin
A four year experimental study of initial stages of succession on different substrata (sand, peat and gray clay overburden from brown coal mining) was carried out. The substrata were transplanted into two different landscape types in the Czech Republic. Control plots were filled with autochthonous topsoil treated with high temperature vapor. Plots with un-treated autochthonous topsoil were also established. Plant species cover and several soil-biological parameters (soil microbial biomass, basal soil respiration, exchangeable pH(KCl), organic-C extractable by potassium sulfate solution, and nitrate-N content) were measured once a year. Obtained data were mainly processed by unimodal (plant cover data) and liner (soil-biological data) ordination methods. Biological species traits (life span, seed dispersal vector, seed bank type, ecological strategy type following Grime, life form following Raunkiaer) were used to characterize early stages of plant succession. Vegetation and measured soil-biological parameters, except pH(KCl), were significantly changing during four growing seasons. Variance partitioning analysis based on plant species cover data indicated the landscape type to be the main governing factor and physico-chemical characteristics of substrate to be less important during the studied initial stages of succession. The same analysis based on soil-biological parameters showed the reverse result. Great variability of plant species ecological traits was noticed during four growing seasons. The earliest plant colonizers were mainly ruderal, anemochorous terophytes with persistent seed bank. The number of species with C-strategy type increased during the study. The relationship between the average plant species cover and measured soil-biological parameters was also examined during the experimental study of early succession. Direct and indirect ordination revealed the average sum of plant species cover to be weakly positively correlated with soil microbial biomass, basal soil respiration, nitrate-N, potassium sulfate extractable organic-C, metabolic quocient (qCO2) and negatively correlated to exchangeable pH(KCl). The relationship was significant only in the case of microbial biomass and potassium sulfate extractable organic-C. More detailed studies of the relationship between aboveground plant species biomass and soil microbial communities in initial stages of succession are required. Comparability of presented study is limited because not many experimental investigations of similar kind have been presented until now.
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The ten-year development of vegetation cover of the Bečva river flood channel with special regard to ecotones
Lacina, Jan
During the disastrous flood in July 1997 the Bečva river created notable flood channels, which are considerably more complex and wider than the previous technically designed one. In the fall of the vegetation period in 1997 the six most interesting segments between towns Valašské Mežiříčí and Přerov were chosen and left in further natural development. During 10 years the processes of spontaneous succession have been examined by means of repeated phytosociological records on the investigative transects which have been located on various habitats. Dynamic development of river channel and its vegetation communities (from grassy-herbal heath to flood-plain forest and its ecotones) differentiated by hydrologic conditions, topography and grain-size distribution is very notable on the transect near Osek nad Bečvou. It is indisputable that the high-magnitude flood revitalizated the riverine landscape, diversified its character and contributed to the higher biodiverisity.
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Ecotons as a dynamic part of floodplain landscape
Halas, Petr ; Lacina, Jan
Varied mosaic of diverse biocoenoses and ecotons rises by natural fluvial processes in alluvium. Dynamic development of vegetation cover was studied in years 1997 – 2007 in flood river bed of Bečva river. Variable mosaic of biocoenoses and ecotons of Bečva river floodplain is considerably varier than regulated and flood undisturbed riverine landscape of Trkmanka river.
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