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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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Navážka substrátu a inokulace stonožek (Chilopoda) na výsypky po těžbě hnědého uhlí
Voženílková-Aurová, Klára
Piles of upper soil taken from non-disturbed surroundings of the mine were deposited on the spoil heap area denuded by soil slide to accelerate succession and development of soil fauna on colliery spoil heaps. Development of soil fauna was investigated as from May 1995 till May 1998. Epigeic activity of centipedes was monitored by the method of long term pitfall trapping on the tops of the piles, between piles and on the soil slide in the distance of 50 m from the piles (control plot). The development of the centipede assemblage on the piles was similar to that on the reclaimed spoil heaps. .i.Lamyctes emarginatus./i., known as a pioneer species in young successive stage of the heaps, predominated at the beginning of the experiment. Later on, the numbers of .i.Lamyctes emarginatus./i. decreased because of increasing activity of other centipede species, especially .i.Lithobius microps./i..
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Contribution to the changes and evaluation of vegetation on landslides and to the problematic of their phytoindication
Lacina, Jan
Relationships between landslides and vegetation cover were studied in Moravian part of Western Carpathian Mountains on selected plots which were affected by landslides evoked by extreme floods in July 1997. It was founded that landslides rises under various vegetation formation – forestal and non-forestal as well. Landslides change ecological conditions for vegetation markedly. A number of species are bounded to landslides, e.g. Equisetum telmateia, which is possible to identify like landslides guides, don’t like phytoindicators.
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Vývoj půdní fauny na loukách obnovených na orné půdě: Iniciální fáze sukcesního vývoje
Tajovský, Karel ; Pižl, Václav ; Starý, Josef ; Balík, Vladimír ; Frouz, Jan ; Schlaghamerský, J. ; Háněl, Ladislav ; Rusek, Josef ; Kalčík, Jiří
The development of soil fauna assemblages (testate amoebae, nematodes, enchytraeids, earthworms, terrestrial isopods, millipedes, centipedes, collembolans, dipteran larvae) has been investigated in a -field experiment since autumn 1999. Four types of treatment were studied in plots previously managed as arable land: 1) sowing with a native seed mixture, 2) sowing of a 5 m wide central strip with native and the lateral strips with commercial seed mixture, 3) sowing of a 5 m wide central strip with native seed mixture, leaving the lateral strips to spontaneous succession, and 4) leaving to spontaneous succession (abandoned field). The observed increase of qualitative and quantitative parameters of the individual soil animal groups corresponded to the initial phase of successional development. Eurytopic and euryvalent representatives as well as epigeic species of soil micro-, meso- and macrofauna prevailed in the studied treatments during the first years of observation.
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Short-term effects of grass mixtures on nematodes inhabiting agricultural soil in the Bílé Karpaty Mts., Czech Republic - a preliminary study
Háněl, Ladislav
Short-term changes of nematode assemblages were studied in field soil sown with regional and commercial grass mixtures and compared with those in a cultivated field in the course of one year. Total average abundance of nematodes in the grass mixture plots increased rapidly to 1308-2075 x 10 3 ind.m.-2 whereas in the field it remained relatively low (625 x 10 3 ind.m-2). The increase in population densities mainly concerned microbivores such as Panagrolaimus, Paraphelenchus, Aphelenchus and Aphelenchoides (950-1779 x 10 3 ind. m-2) followed by omnivores + predators (178-296 x 10 3 ind.m-2), while increase in plant parasite populations was slower (105-140 x 10 3 ind. m-2). The development of nematode assemblages suggests a great role of accumulation of above-ground as well as below-ground litter supporting microflora and microbial feeding fauna in initial stages of meadow restoration. In older stages, an increase of root density is expected simultaneously with multiplication of plant parasitic nematodes. Early successional development of soil nematode assemblages seemed to be faster in plots sown with regional grass mixture than in that sown with commercial grass mixture.
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Family business
Prchalová, Lenka ; Svobodová, Ivana (advisor) ; Janů, Petra (referee)
The thesis deals with the phenomenon of "Family business". The first part involves theory aimed at the global importance of family businesses, their specifics, definition, strong and weak sides and potential difficulties. The process of succession and its strategy is described in more detailed way enabling future success of family businesses. The second part shows analyses of Czech family companies. There is a comparison with German family companies which might serve for some improvement of the Czech family entrepreneurs. At the end of this thesis, there are three case studies of three Czech family companies. On the basis of their analysis is provided a recommendation of potential solutions of their problematic areas.
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