Domů | O časopisu | Kontakty | Pokyny pro autory | Archiv

Zprávy České botanické společnosti 49/2, 2014


Unar J. & Unar P.
Floristické poznámky z Brna a okolí
Floristic notes from Brno and its vicinity

This article presents some interesting botanical finds in the city of Brno and its surroundings. The observations focused on native endangered species and species with decreasing occurrence. Species frequencies were compared with those from a survey of synanthropic flora in the city of Brno made at the end of 1970s. Some rapidly spreading alien species were registered. In this respect the occurrence of some rare orchids among blocks of flats in the Lesná district is interesting. More intensive management of the urban space has caused extinction of some previously common synanthropic species (Artemisia annua) or a significant decrease in their occurrence (Heracleum mantegazzianum). An increasing number of localities of Artemisia tournefortiana, Duchesnea indica, Geranium sibiricum or Bunias orientalis has been observed.

Uher J.
Vrbina brvitá (Lysimachia ciliata) - nově zavlečený druh v květeně České republiky: historie jeho šíření v Evropě
Fringed Loosestrife (Lysimachia ciliata) - an alien species new to the Czech flora: history of its introduction in Europe

North American Loosestrife, Lysimachia ciliata, was recorded on waterlogged backfill soil at the Bruksa Pond affluent in a floodplain forest near Břeclav, South Moravia. The plants have certainly escaped from cultivation, as the species is becoming popular in gardens, and appeared in the wild in Western Europe already two centuries ago. In Central Europe, it is the first record of this species in the wild. However, despite its high vitality, it may be casual and temporary. As this species is easy to recognise due to its non-punctate leaves, ciliate petioles, and nutant solitary flowers with supervolute corolla lobes, each enclosing one stamen alternating with staminodia, it is unlikely to be confused with any native species of the genus Lysimachia.

Malíček J. & Steinová J.
Rostliny a lišejníky acidofilních stepí ve středním Povltaví
Vascular plants and lichens of acidophilus steppes in the Middle Vltava Region (Central Bohemia)

Fifty years after the description of the grassland association Artemisio campestris-Corynephoretum canescentis, the current state and diversity of vascular plants and lichens were studied. It is a very local community known mostly from the Middle Vltava Region. The grasslands occur on shallow sandy soils based on granodiorite bedrock and are concentrated at the edges of pine forests and pastures. Almost one half of the original localities have been destroyed. Fourteen localities were investigated in detail. The vegetation has changed more or less to another type of grassland vegetation because of lack of management, but several sites are still well preserved and inhabited by typical communities. Acidophilous steppes, as described originally, are characterized by the presence of psammophilous plants (e.g. Aira caryophyllea, Corynephorus canescens, Helichrysum arenarium), high diversity and abundance of Cladonia species, and by the presence of a range of xerothermic plants (e.g. Chondrilla juncea, Petrorhagia prolifera, Veronica prostrata).

Gálová A. & Hájková P.
Utricularia vulgaris v Hodonínské Dúbravě
Utricularia vulgaris in Hodonínská Dúbrava forest

The critically endangered species Utricularia vulgaris has been re-discovered in Hodonínská Dúbrava forest after more than 20 years. Young plants were observed at one of the waterlogged terrain depressions (MS15) in spring 2014, but they did not survive to flower. Macrofossil analysis demonstrated the presence of viable seeds of U. vulgaris in the sediments of three wet depressions (MS3, MS4, MS15). The age of the sediment with viable seeds was up to 100 years, which suggests that the seed bank of the species is highly persistent. The presence of seeds in the youngest samples at localities without recent presence of this plant suggests that the species might occasionally have appeared and flowered also within the past 20 years. The most probable reason of the decline of U. vulgaris in Hodonínská Dúbrava is a lowering of the water table. Appropriate restoration management should be considered.

Zítková I.
Srovnání druhového složení a diverzity cévnatých rostlin a mechorostů polopřirozených lesů a kulturních smrčin
Comparison of species composition and diversity of vascular plants and bryophytes in seminatural forests and spruce plantations

The effect of spruce plantations at sites originally covered by deciduous forests on understory species has only rarely been studied. The aim of this work is to compare the diversity and species composition of understory in natural stands dominated by European beech (Fagus sylvatica) and cultural stands dominated by Norway spruce (Picea abies). The study was carried out in the Blanský les Protected Landscape Area in South Bohemia (Czech Republic), where both cultural spruce forests and natural beech forests are available. Data for the comparison were obtained by means of phytosociological records. In total, 60 relevés were recorded (30 in beech and 30 in spruce stands). A maximum distance of 350 m between pairs of relevés was chosen to include similar habitat conditions for both stand types. The analysis shows that there is no significant difference in the diversity of plants in beech (13.43 species on average) and spruce stands (13.8). Nevertheless, species composition in the studied stand types is different. Beech forests are characterized by the occurrence of vascular species typical of mesophilous forests (e.g. Galium odoratum, Milium effusum, Luzula luzuloides) whereas mosses are more frequent in spruce plantations (Dicranella heteromalla, Dicranum scoparium). From the analysis of background environmental factors we found slope, aspect, coverage of tree layer, rainfall and stand type (beech/spruce) to be insignificant. In contrast, the factors sample pair (i.e., pure effect of the locality) and altitude are significant and explain most of the variability in species composition.

Kabátová K., Rydlo Jan & Rydlo Jar.
Echinocystis lobata na březích Berounky
Echinocystis lobata on Berounka riverbanks

The Berounka River flows from Plzeň to Prague in W and C Bohemia and has a total length of 138.7 km. Occurrence of the invasive annual species Echinocystis lobata was repeatedly investigated along the entire river. Number of its localities (half-kilometre long sections) and length of its stands were recorded. In 1982, the species was not yet registered at all. In 1992, a single locality appeared near Plzeň and E. lobata has been spreading since then. In 2002, it occurred at 189 of a total of 278 investigated sections of the river. An extreme summer flood mid August 2002 caused a moderate decrease in number of localities to 155, which was followed by an increase again. Three years after the flood (in 2005) the number of localities was 195. A less extreme flood in early June 2013 destroyed young plants and caused reduction of the number of localities to 97.