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Coppicing is uncommon in Poland; however, some remnants of a previously coppiced oak forest persist in the foothills of the Sudety Mountains (southern Poland). Some of these forests are considered as a kind of thermophilous oak forest, classified as habitat 91I0 in the European programme Natura 2000. As an example of previously coppiced sessile oak (Quercus petraea (Matt.) Liebl.) forest in Poland, the vegetation and environmental factors in the “Wąwoz Lipa” reserve (area 101 ha, altitude ca. 400 m a.s.l.) were surveyed. Canonical correspondence analysis showed a basic compositional gradient of vegetation related to the content of coarse fragments in the soil, light availability and soil pH. The number of species per plot was not correlated with any particular environmental variable; in general, the plant species number and cover decreased in the most exposed sites, where the heat load was highest. We hypothesize that the higher number of species in some plots was the results of an edge effect: this occurred in transitional zones between the most exposed sites, which work as refuges for light-demanding, drought-tolerant species, and less exposed sites, with vegetation typical of acidophilous oak forests. The land relief also allowed the spread of species typical of mesophilous forests, which found refuge in the shaded, wet gorges. Thus, the specific land relief, along with previous coppice management, allowed the coexistence, probably temporally, of species of plants considered typical of different habitats.
The objective of this study was to analyse the diversity of pine and spruce bog forests on the domes of Carpathian raised bogs located in the Upper San River Valley. In order to determine the present species composition, 59 phytosociological relevés were performed (32 within spruce forests, and 27 in pine forests). For all relevés, the Shannon-Wiener index, evenness index and mean Ellenberg indicator values were calculated. Detrended correspondence analysis was conducted in order to determine the degree of similarity between distinct units of vegetation and to identify the main environmental gradients that have an impact on species composition. The results revealed considerable similarities between the ground vegetation of both spruce and pine forests growing on peat substrate. Within pine forests there was a greater proportion of certain plant species characteristic of raised bogs, and plants typical of bog coniferous forests. The ground flora of spruce forests was more diverse. Although spruce forests predominantly contained species typical of raised bogs, there was also a group in which Molinia caerulea predominated. Ellenberg indicator values typical of pine forests lay within ranges that were characteristic of spruce forests, but pine forests occupy more humid, more acidic and poorer habitats than most patches of spruce forests. Both spruce and pine bog forests were developed as a result of the colonization of open bogs, but the time-scale and rate of intensity were different. Palaeobotanical and historical data indicate that the Scots pine first reappeared on the domes of raised bogs in the first half of the 20th century. The concept that the spruce forests are older than those of pine is supported by their greater habitat diversity. Conversely, the younger age of pine forests is confirmed by their low habitat diversity, and greater proportion of photophilous raised-bog species.
The study examine s the vegetation diversity (235 herbaceous species) in variable road-site types in terms of life history components (life traits) like life form, type of pollination, seed dispersal, spreading ability, life strategy according to Grime’s classification, and in terms of habitat preferences using Ellenberg’s indicator value (in relation to light, temperature, moisture, nitrogen, soil pH and soil salinity). Plants registered as alien species were evaluated also according to invasive status, level of abundance, introduction mode and land use habitat. Study localities (9 sites) were situated in the Českomoravská highlands and the South Bohemian regions (Czech Republic). The plant species were recorded in the bands (width in range of 1.5–3.0 m) along the verge of two types of roads (motorways with median stripes) and secondary roads (II and III classes). In total – road length of about 15 km and the total area of roadside vegetation of about 8 ha were surveyed. The annual/therophyte species with a tendency to seed dispersed by wind, preferring a light and dry habitat, and having the RC (competitive-ruderal) life strategy were mainly found along the motorways. It means that road verges along motorways are quite insolated and constitute the dry habitats, probably suitable for ruderal, weedy, non-native, and invasive species. On the contrary, species with a tendency to vegetative reproduction and the C (competitive) strategy occur mainly along the secondary roads. It seems that the secondary roads are alternative habitats for grassland flora. Species occurred on the verges of the secondary roads do not belong to the particular group of the life traits. The salt tolerant species Puccinellia distans (Jacq.) Parl. was found along all types of roads. Almost 24% of all recorded herbaceous species growing in road-sites were alien species.
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