In this study, the chronic effects of Ampicillin on survival, reproduction and growth of Daphnia magna was monitored during 21 days exposure test. The results showed that Ampicillin strongly affected on life history traits of Daphnia magna, i.e. 47% reduction of survival proportion, lower 68% reproduction than the control, and reduction in body length and in the intrinsic population rate, especially at its highest concentration. The antibiotics especially Ampicillin should be included int the Vietnam guidelines for environmental and ecological protection.
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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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The investigations of the impact of disturbance severity on recruitment of clonal plant species were preformed in three Molinietum caeruleae patches dominated by small meadow species (MC), or prevailed by tall grasses (GR) or overgrown by willows (SA). The meadows were located in Vistula valley close to Kraków agglomeration, southern Poland. In above menntionned patches ten permanent experimental plots were randomly arranged. Each plot was divided in four subplots measured 900 cm2 represented undisturbed control, low level of disturbance (the litter and the moss layer removal), intermediate level of disturbance (the litter, moss and above-ground vegetation removal), high level of disturbance (the litter, moss and the plants removal as well as top soil raking). The colonization of gaps was observed in the years 2008–2010. Irrespective of patch character, the greatest species richness and seedling abundance were observed in gaps, which occurred in result of intermediate disturbances. Weaker recruitment rates were recorded in openings left after disturbances of low- and high severity, while in fully compact herb layer no seedlings were found. In MC patch, regardless of treatment in all openings similar spectra of life history traits were observed. In seedling pool of all subplots appeared taxa creating below ground organs of clonal growth. In all subplots dominated species with intermediate values of lateral spread, numerous vegetative descendants, short-lasting stems and no persistent genet integration. In sites GR and SA in openings left after weak disturbances appeared species with below- and aboveground organs of clonal growth. The majority of them characterized by slight lateral spread, low number of vegetative offsprings, long lifespan of shoots and persistent genet integration. The abundance of taxa creating underground clonal growth organs, with considerable vegetative spread, high production of daughter ramets, short lifespan of shoots and not enduring genet integration increased gradually and significantly with disturbance gradient. Although the greatest recruitment rates were found in gaps left after removal of litter, moss and above-ground parts of plants, the most effective way for conservation of Molinietum caeruleae meadows appeared to be creation of different severity disturbances. Such treatment contributes to maintenance of heterogeneity of clonal species composition, especially in patches in advanced successional stages
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The herb layer recovery in post-agricultural woods adjacent to ancient forests has not yet been studied for the wettest European woodlands, like those with black alders (Alnus glutinosa L. (Gaertn.)). Therefore, the studies aimed at: I. checking which herbs from the Polish list of ancient woodland species that are present in the alder woods show an association with these woods (AAWS=Ancient Alder Woodland Species); II. presenting their ecological profile (spectra of life forms, life strategies, dispersal modes, phytosociological affinity, and Ellenberg indicator values), and III. comparing the dispersal potential and other traits of species recorded more often in ancient woods (AAWS) vs the Polish ancient woodland indicators frequently present in ancient and recent alder woods (OAWS = Other Ancient Woodland Species). The survey was carried out in Alnus glutinosadominated woodlands, located in south-western Poland. The study sites are located within large forest complexes, where they occupy either periodically waterlogged sites or other places with a high level of groundwater. In the case of ancient woods, wet types of an oak-hornbeam community (Tilio-Carpinetum Tracz. 1962 or Galio-Carpinetum Oberd. 1957) (11 sites), alder-ash carrs (Fraxino-Alnetum W. Mat. 1952) (12 sites) and typical wet alder woods (Ribeso nigri-Alnetum Sol.-Górn. (1975) 1987) (10 sites) were investigated. The ancient woodland sites varied in size from 0.73 ha to 15.54 ha. Recent woods, adjacent to these sites, included black alder stands planted on former meadows. The area of their patches ranged from 0.72 ha to 8.6 ha. Post-agricultural woods represented the following age classes: up to 10 years, 11-20, 21-30, 31-40, and 41-50 years. The process of colonization of recent woods by woodland flora was investigated in 33 transects, approximately 80 m in length by 4 m in width, consisting of 10-12 quadrates, 16 m2 each, laid out at intervals of 4 m, perpendicularly across the ancient-recent border. In total 131 quadrates in the ancient wood, 198 in the recent woodland, and 34 in the ecotone zone were investigated. The migration rates (m yr[^-1]) based on the occurrence of the farthest individuals, were calculated for over 50 woodland species. The original lists of species obtained from the transects were completed after detailed inspections of the whole area of adjacent forest sectors where the studies on the colonization process were undertaken. Then, the frequency of herb layer species in ancient and recent woods was compared (Fisher exact probability test). The mean migration rates of species from the AAWS and OAWS groups were calculated. Although 62 herbs from the group of ancient woodland indicators for Poland were recorded in the course of the studies, only 21 of them occurred significantly more often in alder woods. The mean migration rate for herbs from AAWS was significantly lower (0.68 m yr[^-1]) than in the case of the OAWS group (1.54 m yr[^-1]). This indicates that true woodland herbs differ distinctively in their dispersal potential. Species from those two sets also showed some differences in their ecological requirements. Such results allow a conclusion to be reached that in wet and fertile recent forests adjacent to ancient source woods, recolonization of the herbaceous layer by typical woodland flora proceeds faster than in other, less fertile and drier habitats. This in turn explains why many true woodland species do not occur in ancient woodland sites exclusively. They are often recorded in recent woods, as they are able to colonize such sites reasonably fast.
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Heavy metal contaminations can be considered as one of the serious environmental pollution and may have adverse effects on different organisms. This study was carried out to search how rearing the cabbage aphid (Brevicoryne brassicae L.) on heavy metal contaminated host plants affects aphid life history traits. The results revealed that both radish and cabbage host plants (Raphanus sativus L., Brassica oleracea L) contaminated separately with copper (Cu) and lead (Pb) have an important effects on life history traits of aphids. The life history traits such as fecundity (number of offspring produced per day) and fitness (intrinsic rate of population increase) were reduced about 30% when aphids were reared on contaminated host plants. However, no concise effects were found in case of development time (from birth to beginning of first reproduction). Reproduction potential of aphid population signficantly decreased and their mortality tended to be higher about 20 % on contaminated host plants. Cu and Pb had different impacts on life history traits of aphids living on the same host plant, and the same heavy metal had different effects on aphid life history traits across host plants. The uptake of Cu and Pb by cabbage aphids feeding on contaminated host plants affected life history traits due to direct toxity or reduced food quality of host plants. Results are discussed in the context of the possible effects of heavy metal pollution on herbivore-host plant relationships. This study indicates that aphid-host plant system has several advantages to study the heavy metal pollution effects on food chain in nature.
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A hypothesis has been put forward that low pH or high concentration of total phosphorus (TP) and dissolved organic carbon (DOC) in the lake water are the factors responsible for observed extinction of the population of Luronium natans (L.) Raf., protected macrophyte species from the group of isoetids. A study was performed on 525 generative individuals collected from 21 lakes in Pomeranian Lakeland (NW Poland) and a correlation between the biometric characteristics and environmental conditions in the lakes was tested. The following life history traits have been analysed: size of individuals, their fecundity and allocation of biomass. The greatest and most fecund individuals grow in the lake water of pH 6.1-7.0, poor in TP (10.1-20.0 [mi]g dm^-3) and DOC (3.5-6.0 mg C dm^-3). The allocation of biomass of the individuals growing in the optimum conditions is as follows 46-54% in the leaves, 22-31% in the roots and 20-27% in the rhizome. In the lakes with water of pH < 5.0 or of TP3 > 20.1 [mi]g dm^-3 and DOC > 6 mg C dm^3, a statistically significant decrease in the size of the individuals and unfavourable changes in the biomass allocation are found. The main environmental factor responsible for dying out local populations of Luronium natans is a decrease of pH below < 5.0.
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