The Central European flora is an important source pool of plant species introduced to many regions throughout theworld. In this study,we identified a total of 759 plant species of the Central European flora that are currently recognized as alien species in Australia. We explored temporal patterns of introduction of these species to Australia in relation to method of introduction, growth form, naturalization status and taxonomy. Across all species, substantially larger numbers of species were introduced between 1840 and 1880 as well as between 1980 and the present, with a small peak of introductions within the 1930s. These patterns reflect early immigration patterns to Australia, recent improvements in fast and efficient transportation around the globe, and emigration away from difficult conditions brought about by the lead up to the Second World War respectively. We found that the majority of species had deliberate (69%) rather than accidental (31%) introductions and most species have not naturalized (66% casual species, 34% naturalized species). A total of 86 plant families comprising 31 tree species, 91 shrub species, 533 herbaceous species and 61 grass species present in Central Europe have been introduced to Australia. Differential patterns of temporal introduction of species were found as a function of both plant family and growth form and these patterns appear linked to variation in human migration numbers to Australia.
Four lamprey species and 55 fish species are considered autochthonous taxa in the Czech Republic. In recent years, as a result of spontaneous migrations, the native ichthyofauna has been increased by three species Sander volgensis, Gymnocephalus baloni, Proterorhinus marmoratus) which, in view of their autochthonous occurrence in the Central European region, are evaluated as native. At present, according to the criteria of the IUCN (2001) version 3.1, two lamprey species and 6 fish species are evaluated as “regionally extinct”. Most of these taxons are denoted as anadromous. One species has been classified in the category “Extinct in the wild”. Two lamprey species and 25 fish species are considered to be endangered to various extent: one lamprey species and 10 fish species are classified as “Critically endangered”; one lamprey species and 5 fish species as “Endangered”; ten fish species as “Vulnerable”. In the course of the past two centuries, attempts have been made at introducing about 30 fish species (see Lusk et al. 1998, Hanel 2003); of these, the introduction of 11 species can be evaluated as successful. Only four non-native species have established stable and naturally reproducing populations in natural conditions (Pseudorasbora parva, Carassius auratus, Ameiurus nebulosus, Gasterosteus aculeatus).
This paper describes the reproductive characteristics of 93 neophytes (alien species introduced after 1500 A.D.) of the flora of the Czech Republic and compares trait values between naturalized invasive and naturalized non-invasive neophytes. Species were sampled and seed collected in the field from multiple localities in the Czech Republic. Traits related to seed production (propagule number per plant and per population), dispersal (propagule size, length/width ratio and weight; buoyancy; epizoochory; terminal velocity) and establishment (germination; seedling relative growth rate; seedling establishment) were measured for each species either in the field, in a common garden experiment or in the laboratory. Invasive species significantly differ from naturalized non-invasive species in propagule length/width ratio (by having lower ratio, i.e. more rounded propagules) and fecundity (invasive species are more fecund, both per individual plant and in terms of the population propagule production). Invasive species have proportionally fewer seedlings establishing in the autumn and better capacity for dispersal by wind than non-invasive species. The results for several traits differ depending on whether or not the effect of phylogeny is included in analytical models. Considering species relatedness expressed as a taxonomic hierarchy, invasive species have lighter propagules and higher population propagule numbers, and marginally significantly differ in producing more propagules per plant and having higher capacity for dispersal bywater.We found that most variation in invasiveness is linked to variation among species within genera. This distribution of relatedness means that predictions of whether a species will become invasive cannot be based on traits of the relatives of the given species at higher taxonomic levels. The distinction made in this paper, i.e. invasive species vs. naturalized but non-invasive species, can potentially contribute to a deeper understanding of the role of traits associated with invasiveness because the crucial transition from the naturalized to invasion stage is rarely addressed in invasion ecology.
In the subcontinental, semiarid lowland region of Central Bohemia (Czech Republic), continuous human impact acting together with diverse natural environmental conditions resulted in the present extraordinarily complex pattern of vegetation. Three radiocarbon-dated pollen diagrams for the area indicate that this complexity results from past vegetation development. During prehistory, places suitable for settlement (with respect to climate, geology, hydrology, etc.) were colonized and transformed first. This resulted in a diachrony in vegetation development due to human activity starting in the first half of the Holocene. This caused an increase in diversity in the region as plant species persisting from previous periods, along with those associated with different agricultural practices, increased. Local abiotic factors affected not only the chronology of human impact but also its specific effects on the ecosystem. Anthropogenic pressure may have had different effects under different conditions. Human population pressure was the mediator between the abiotic diversity and selectively transformed vegetation suitable for the respective habitats. Differences in the chronology of human impact, mixed oak woodland degradation, and the chronology of beech, silver fir and hornbeam expansion are documented for the different ecological zones of the study area. These differences shed light on the mechanisms resulting in some of the important changes in Holocene vegetation. In the absence of man, the decline in mixed oak woodlands, typical of the Middle Holocene in Central Bohemia, would have been probably much slower and less extensive. Unlike in the uplands and mountains, the expansion in the area of beech, silver fir and hornbeam would have been insignificant. The present vegetation resulted to a large extent from management during High Middle Ages. There is almost no continuity in vegetation from the late prehistory to the present.
Species richness and above-ground biomass of vascular plants and bryophytes of poor acidic fens (the Sphagno recurvi-Caricion canescentis alliance), rich Sphagnum fens (the Caricion fuscae and Sphagno warnstorfii-Tomenthypnion alliances) and calcareous spring fens (the Caricion davallianae alliance including tufa-forming spring fens) were studied. The study area was in the western parts of the Outer Carpathians in the border region of the Czech and Slovak Republics. The numbers of species were recorded in plots ranging from 0.00196 to 16m2 and correlated with chemical factors and above-ground biomass. The chemical properties of springwater (mainly pH, conductivity, Ca2+, Mg2+) were the main factors influencing the species richness of vascular plants. Tufa-forming calcareous fen communities (Carici flavae-Cratoneuretum) had the highest species richness of vascular plants. In contrast, the highest species richness of bryophytes occurred at pHneutral sites, in peat forming calcareous fen communities (Valeriano-Caricetum flavae) and in those with Sphagnum warnstorfii and S. teres. Bryophyte species richness of small plots was correlated with the iron concentration in the springwater. The differences in species richness of calcareous fens were related to the mowing regime. Litter mass had a negative effect on the species richness of vascular plants. Mosses responded to high amounts of litter or vascular plant biomass by a significant decrease in biomass. Two types of Sphagnum fens: (a) strongly dominated by Sphagnum flexuosum or S. palustre (rich in phosphates) and (b) polydominant (poor in phosphates), were also compared. In the former, the slope of the regression for the dependence of bryophyte species richness on plot size was less steep.
The current state of the taxonomy of Rubus ser. Discolores in the Czech Republic is summarized. Since 1995, when the group was treated in the Flora of the Czech Republic (Holub 1995), six new species have been recognized, some of which are also known from adjacent areas. They are described in the present study: R. austroslovacus Trávníček, R. flos-amygdalae Trávníček et Holub, R. guttiferus Trávníček et Holub, R. parthenocissus Trávníček et Holub, R. pericrispatus Holub et Trávníček and R. portae-moravicae Holub et Trávníček. The first five belong to the group of triploid species close to R. montanus Lej. and R. grabowskii Weihe, whilst R. portae-moravicae is related to R. praecox Bertol. Two additional species, originally recognized under provisional names, were found to be identical to species described earlier: R. perperus H. E. Weber and R. phyllostachys P. J. Mueller; the latter is also found in Slovakia. At present, 17 indigenous species, one naturalized alien (R. armeniacus Focke) and one rare garden escape (R. ulmifolius Schott) of the ser. Discolores are known to occur in the Czech Republic. Distribution data and a key for the identification of all the species are presented.
Two new species, Taraxacum maricum and Taraxacum cristatum, of the section Erythrosperma from Central Europe are described in this paper. These species are similar to western European taxa, T. maricum to T. proximum, and T. cristatum is morphologically close to T. scanicum. Both new taxa are triploid apomictic microspecies. Specific characteristics, information on distribution and ecology and comparison with similar species are presented. Pictures and distribution maps of the new species are also included.
The composition of the vegetation of fishpond mires in the Třeboň Basin (Czech Republic) was studied in relation to temporal fluctuations in certain environmental factors. The water-table depth, water pH and electrical conductivity at 49 permanent plots were measured at approximately threeweek intervals from March to October 2003. Minimum, maximum, mean, median and variation in the above-mentioned environmental factors were correlated with vegetation composition. The most important environmental factors explaining the variation in vegetation were mean pH and maximum water-table level. Median conductivity increased with increase in waterlogging and eutrophication. Some seasonal trends in the dynamics of these parameters were observed. The lowest conductivity was in spring, increased continuously throughout summer and peaked in autumn. In contrast, water level decreased in summer, when evapotranspiration was greatest, and rose in autumn after heavy rainfall. The pH increased from March to June, then was stable and decreased at the end of summer. Seasonal trends were generally identical in all vegetation types. The fluctuations in the environmental factors were so considerable that they may influence the reliability of vegetation environmental analyses.
A new genus, Vindobonella gen. n. (Acerentomidae s. l.), and a new species, Vindobonella leopoldina sp. n., are described from Vienna. The new genus belongs to a group characterized by a reduced labial palp and a non-modified striate band on abdominal segment VIII.
Cílem práce je diskutovat význam her v předliterárních společnostech. Této společenské aktivitě je dosud věnována nedostatečná pozornost především, co se období evropské prehistorie týká. Článek je založen na hypotetické interpretaci rondelů jakožto ohraničeného místa pro provozování her. Na důležitost fenoménu her z hlediska jejich společenské funkce poukazuje úvodní teoretická pasáž. Faktografický základ textu tvoří formální a metrické srovnání rondelů několika archeologických kultur studovaného období. Interpretační rámec doplňují etnohistorické informace z oblasti Mezoameriky o významu institucionalizované míčové hry pro fungování tamní stratifikované společnosti. and The aim of this contribution is to discuss the significance of games in preliterate societies. To date, not much attention has been paid to this social activity, primarily concerning the period of European prehistory. This article is based on a hypothetical interpretation of rondels as an enclosed area for playing games. The introductory theoretical passage refers to the importance of the phenomenon of games in terms of their social function. The factual basis of the text comprises a formal and metric comparison of rondels of several archaeological cultures in the studied period. The interpretational framework is supplemented by ethnohistorical information, from Mesoamerica, on the significance of an institutionalised ball game for the functioning of the stratified society there.