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A study on vascular flora of a Zn–Pb ore spoil heap of the “Orzeł Biały” mining and smelting works in Bytom, Poland, was carried out in the 2017–2018 growing seasons. The aim of this study was to: (i) present the characteristics of current vascular flora that colonizes the Zn–Pb heap, (ii) describe its dynamic tendencies and directions of changes after 15 years, and (iii) identify species that can be useful for planting as a part of biological reclamation. Ninety-two mostly native species of vascular plants, belonging to 36 families and 77 genera, were found on the examined heap. In the spectrum of life forms, hemicryptophytes prevailed over therophytes and geophytes. The most numerous ecological groups were ruderal and meadow species. As regards life strategies, highly competitive species and taxa with mixed CSR strategies dominated. The basic mode of seed dispersal was anemochory. In terms of habitat preferences, species associated with moderately light, warm, fresh, neutral, and medium fertility soil dominated in the species composition of the studied flora. In 2017–2018 compared to the 2002 growing season, statistically significant differences were found in the origin, life forms, ecological groups, life strategies, mode of seed dispersal of species and their habitat preferences relative to light, temperature, pH, and productivity. Frequently recorded pseudometallophytes (Agrostis capillaris, Cardaminopsis arenosa, Daucus carota, Deschampsia caespitosa, Leontodon hispidus, Plantago lanceolata, Silene vulgaris, Rumex acetosa) can be used for planting as part of biological reclamation of the area.
The prediction of species response to human activity is of great interest in contemporary restoration ecology. The purpose of the article was to analyse which species life history traits and species habitat preferences are important during succession after the abandonment of mining activity in a sand-pit. During a 15-year period (1996–2010), 176 phytosociological relevés were placed within vegetation patches of different ages and divided according to soil moisture, thus forming two series of chronosequences that ranged from 0 to ca. 50 years. The datasets were analysed using both DCA/CCA ordinations and regression trees. The successional gradient, apart from the theoretically predicted replacement R by C strategists, revealed the occurrence of stresstolerant ruderals and competitive ruderals in the early successional stages. However, differences were observed between the wet and dry series. On dry soils the ruderals, anemochorous and windpollinated species dominated in the early phases. In the middle successional phases, a preponderance of anemochorous species (nanophanerophytes, light or semi-shade demanding species), nitrogen-poor and competitive ruderals or species typical for nitrogen-rich soils was recorded. In the late successional stages, species with both the ability of vegetative and generative reproduction appeared. On the other hand, on wet sites in the early successional phases, species with vegetative growth, hydrophytes, chamaephytes and stresscompetitors prevailed. Later in the succession, they were replaced by insect-pollinated species in nitrogen rich habitats and stress-tolerant ruderals on less fertile habitats. Finally, competitors started to prevail. Knowledge of the environmental conditions of a given site, the ecological processes and species biology can assist in achieving the desired goals or in initiating or enhancing succession on some disturbed sites.
In this study we analyzed gaps originated in different seasons of the year vs. places of close vegetation in calcareous grasslands in terms of their suitability for seedling germination and establishment. Gaps, irrespective of the time of their origin, significantly promoted seedling emergence as compared with close swards. However, the season of gap creation influenced the rate of seedling germination/emergence. Seedlings occurred more frequently in autumn and spring gaps than in the summer ones. The highest mean number of seedlings and of their species were noted in autumn openings. However, the subsequent survival of seedlings in autumn gaps was low. On the contrary, in spring gaps juveniles occurred with the significantly highest mean number, frequency and species richness. The above results pointed to the positive, although very limited role of artificially created gaps as places favouring seedlings establishment.
Brachypodium pinnatum belongs to native grasses which could dramatically decrease the biodiversity of calcareous grasslands, therefore, an examination of the mechanisms of its expansion is of prime importance for their conservation. We studied the genetic structure of 12 subpopulations of the expansive grass B. pinnatum in a heterogeneous landscape with AFLP markers, aiming at determination whether spatial isolation influences the genetic diversity and the population genetic structure of this species. A high level of overall (79%) and within population polymorphic loci (38–44%) were found and 220 different genotypes were distinguished among the 252 samples analysed. No significant population structure nor isolation-bydistance were found, despite their long-time fragmentation history. This confirms that isolation of calcareous grasslands in a landscape cannot prevent the expansion of B. pinnatum grasses because of the high generative dispersal ability. Subsequent quick and extensive clonal growth of this species enables the successful establishment. In most cases mowing or grazing is sufficient to keep this species at a low density within ancient grasslands and to prevent seed and pollen dispersal, but not for restoration of species-rich calcareous grasslands.
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