Flora differentiation among local ecotopes in the transzonal study of forest-steppe and steppe mounds

Flora similarity was assessed using complete floristic lists of five ecotopes in each of four mounds along the transect from meadow steppes to desert steppes. It was found that the circumapical similitude of floras is more significant than the expositional similitude. Soil analysis in separate ecotopes showed that regular changes in the biogeochemical features are manifested along the topographic gradient and under the effect of the insolation exposure of slopes in local (mound) ecosystem

The floristic differentiation of microhabitats within kurgans in the desert steppe zone of Southern Ukraine

Results of the studies on the floristic biodiversity of the kurgans in the Pontic desert steppe of the Black Sea Lowland (Kherson Region) are presented. Twenty-six of about 130 kurgans higher than 3 m, distributed over an area of approx. 1500 km2, were surveyed and the flora of 5 microhabitats within every kurgan (top, southern and northern slope, southern and northern foot) was examined. The richness of the kurgan flora is estimated at 305 species. Species of alien origin constituted 23% of the total flora, which indicates limited anthropogenic influence. Species of two classes, Festuco-Brometea and Stellarietea mediae were predominant, which also confirmed the semi-natural character of the kurgan flora. The lowest number of species was recorded on top, which was relatively rich in synanthropes, particularly therophytes (Stellarietea mediae). The north side was richer in species than the south side of the kurgans. Steppe species were the most stable and important component of the flora of the slopes (45-47% of the species represented the class Festuco-Brometea). The total flora of the foot contained more species and was more diversified than the flora of the slopes (although the mean number of species was similar in both habitats), but each species occurred at low frequency. There was a higher proportion of species which were introduced from the area surrounding the kurgans, e.g. weeds, halophytes, meadow species, as well as trees which are rarely found in the desert steppe zone. In spite of the small size of the kurgans, significant differences between the floristic composition of the various microhabitats were detected

Central European botanic gardens as centres of dispersal of alien plants

The aim of the work was to estimate the specific role that Central European botanic gardens play in the dispersal of alien plants, which results from the wide variety of plants cultivated in the gardens and regular international exchange of plant material between these institutions. We compared the results of recent field studies (in eight Polish botanic gardens) and a review of older literature data and herbarium collections (from Central European botanic gardens). We found that in Poland the proportion of botanic garden escapes was lower (3%) than would be expected from the "tens rule". Botanic gardens have played a considerable role in the development of the synanthropic flora of Central Europe in the last 200 years. We determined a group of species introduced through a network of botanic gardens and propose 5 theoretical patterns to describe the mode and pathways of the early stages of introduction of these species

The structure and differentiation of the synanthropic flora of the botanical gardens in Poland

Floristic studies were carried out in eight botanical gardens in Poland in the years 1992-1999. It was demonstrated that the spontaneous synanthropic flora of the gardens consisted of 1092 taxa in the rank of a genus or lower, among which alien species constituted 55% of the flora studied. Ergasiophygophytes, of which the introduction is closely associated with the activities of the botanical gardens, dominated in the latter group of species. It appeared that the flora of the studied botanical gardens was rather similar. However, the structure of the flora of different spatial units (six types of microhabitats) distinguished in the particular gardens varied, which was associated with the various management practices. The flora of microhabitats identified in the gardens differed with respect to the number of taxa and spectra of geographical-historical groups of species and life forms. Ruderal sites, arable lands and roadsides supported the highest number of taxa (the flora of the above spatial units was represented by 646, 645 and 597 taxa, respectively). Moreover, they were characterized by a high proportion of annual plants in the flora (43, 38 and 34%, respectively) and by a relatively small representation of apophytes (39% in all the three types of microhabitats). The flora of wet areas and parks was, however, poor in species (154 and 403 species, respectively), but relatively rich in apophytes (72 and 55% of the flora, respectively) and with a low contribution of therophytes (19 and 20%, respectively). The present data were compared with the findings of other authors who investigated the synanthropic flora of cities in which the botanical gardens were located. The comparative analysis of the flora of Poznań and Łódź showed a great richness of species (in relation to size of the area studied) and a high incidence of aliens (especially those, which had not become established permanently) in the botanical gardens. However comparative studies of the flora of Warsaw and that of the two botanical gardens established in the city revealed that the proportion of alien species was lower in case of these gardens. In Warsaw the flora of areas, which had been managed in the same way as those of the botanical gardens, was also investigated. It was found that the botanical gardens in Warsaw were more similar to cemeteries with respect to the structure of flora than they were to the allotments. The present study showed that the high variability of flora within the particular gardens is attributed to the different ways the area is utilized

The floristic differentiation of microkhabitats within kurgans in the desert zone of Southern Ukraine

Moysiyenko, I. The floristic differentiation of microkhabitats within kurgans in the desert zone of Southern Ukraine / B. Sudnik-Wojcikowska, I. Moysiyenko // Acta Societatis Botanicorum Poloniae. - 2008. - Vol. 77. - N 2 . - P. 139-14

Anthropogenic elements of the Ukrainian landscape and the problem of local steppe restoration

Anthropogenic elements of the Ukrainian landscape and the problem of local steppe restoration / B. Sudnik-Wojcikowska, I. Moysiyenko // Annales UMCS. - 2011. - Sectio C. - V. 66, N 1. - P. 85-103

Impact of the invasive species Elaeagnus Angustifolia L. on vegetation in Pontic desert steppe zone (Southern Ukraine)

The Irano-Turanian species – Russian olive (Elaeagnus angustifolia L.) – is one of most commonly planted tree in the shelterbelts in southern Ukraine. The consequences of introduction of the species from windbreaks, into areas of different land use in west and central Pontic desert steppe zone are evaluated. The above steppe is unique on a European scale and exists only in some parts of the Black and Azovian Sea coasts. In recent years, the socio-economical crisis in Ukraine (less intensively cultivation, as well as limited grazing) has been responsible for the intensification of the spread of alien tree species outside the windbreaks. Studies were conducted in Kherson Region, in the immediate vicinity of the Black Sea Biosphere Reserve, where the presence of aliens is undesirable. The analysis of phytosociological material (48 relevés with and without Russian olive) collected from areas of different land use type and limited human pressure (as abandoned field, former intensively grazed solonetz and extensively grazed desert steppe vegetation) show that E. angustifolia can impede the regeneration of the desert steppe. The species creates favourable conditions for the growth of geographically and ecologically alien nithrophilous weeds

Дифференциация флор по локальным экотопам в трансзональном контексте изучения курганов лесостепи и степи

Flora similarity was assessed using complete floristic lists of five ecotopes in each of four mounds along the transect from meadow steppes to desert steppes. It was found that the circumapical similitude of floras is more significant than the expositional similitude. Soil analysis in separate ecotopes showed that regular changes in the biogeochemical features are manifested along the topographic gradient and under the effect of the insolation exposure of slopes in local (mound) ecosystem