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.
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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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The forest communities, which developed on the reclaimed areas of the Kuźnica Warężyńska sand-pit (Silesian Upland), approximate in reference to floristic composition Querco roboris-Pinetum. It occurs from 14 to 45 species in patches. The participation of character species of the Vaccinio-Piceetea class is relatively low and species from other phytosociological units such as Molinio-Arrhenatheretea class appear more frequently and abundantly. The phytocoenoses show significant differentiation which reflects moisture and trophic conditions, so two subassociations were distinguished: wet Querco roboris-Pinetum molinietosum, which is distinguished by wet meadow species, peat-bog plants and rush species and drier Querco roboris-Pinetum typicum with the participation of psammophilous species of the Koelerio-Corynephoretea class. The method [Krzaklewski, 1999], including in reclamation works plant communities, which develop during natural succession, increases success for re-establishment of self-regulating ecosystems and let create mosaic of plant communities, sometimes very interesting from the scientific point of view and valuable for biodiversity conservation.
PL
Fitocenozy leśne, które wykształciły się na objętych rekultywacją obszarach piaskowni Kuźnica Warężyńska (Wyżyna Śląska) są zbliżone pod względem fitosocjologicznym do boru mieszanego Querco roboris-Pinetum. Poszczególne płaty buduje od 14 do 45 gatunków. Udział gatunków charakterystycznych klasy Vaccinio-Piceetea jest stosunkowo niewielki, natomiast większe znaczenie mają gatunki przechodzące z innych klas zbiorowisk roślinnych. Płaty wykazują zróżnicowanie odzwierciedlające panujące warunki wilgotnościowe i troficzne, dzięki czemu możliwe było wydzielenie na tym terenie dwóch podzespołów: wilgotnego Querco roboris-Pinetum molinietosum, którego fitocenozy wyróżniają gatunki wilgotnych łąk, torfowisk czy też zbiorowisk szuwarowych oraz suchszego z udziałem gatunków psammofilnych z klasy Koelerio-Corynephoretea. Zastosowana na tym terenie obok całkowitego zalesiania, metoda sukcesji kierowanej [Krzaklewski i in. 1999], włączająca do procesu rekultywacji, zbiorowiska pochodzące z naturalnej sukcesji zwiększa szanse na odtworzenie się w pełni funkcjonalnych ekosystemów oraz pozwala na wytworzenie mozaiki zbiorowisk roślinnych często interesujących i wartościowych z punktu widzenia ochrony bioróżnorodności.
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