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  • 51.
    Pruchniewicz, Daniel
    et al.
    Wroclaw Univ Environm & Life Sci, Dept Bot & Plant Ecol, Pl Grunwaldzki 24a, PL-50363 Wroclaw, Poland..
    Donath, Tobias W.
    Univ Kiel, Inst Nat Resource Conservat, Dept Landscape Ecol, Olshausenstr 75, D-24118 Kiel, Germany..
    Otte, Annette
    Univ Giessen, Res Ctr BioSyst Land Use & Nutr IFZ, Inst Landscape Ecol & Resource Management, Heinrich Buff Ring 26-32, D-35392 Giessen, Germany..
    Zolnierz, Ludwik
    Wroclaw Univ Environm & Life Sci, Dept Bot & Plant Ecol, Pl Grunwaldzki 24a, PL-50363 Wroclaw, Poland..
    Eckstein, Rolf Lutz
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Effect of expansive species on seed rain and soil seed bank of mountain mesic meadows2016In: Tuexenia, ISSN 0722-494X, no 36, p. 81-96Article in journal (Refereed)
    Abstract [en]

    The degradation of species-rich mountain meadows has been observed in many parts of Central Europe in the last few decades. It is reflected in decreasing species numbers and changes in the proportions of plant species in the aboveground vegetation. Some species are increasing in abundance and eventually dominate the meadow vegetation. There is still a lack of studies explaining how this process is reflected in the soil seed bank. Therefore, the goal of the current study was to test whether expansive species that degrade aboveground vegetation of mountain meadows also influence, quantitatively and qualitatively, seed rain and seed bank. Soil samples were taken from 14 plots in degraded patches and another 14 plots in non-degraded patches. Nearly the same numbers of seedlings were recorded in both meadow types. In both cases, low similarities between aboveground vegetation and soil seed rain and seed bank were observed. Expansive species causing meadow degradation (Calamagrostis epigejos, Festuca rubra, Deschampsia cespitosa and Lupinus polyphyllus) reached cover values of 60-83% in the aboveground vegetation, and a share of up to 36% in the seed rain and seed bank. The mean species richness in the aboveground vegetation and the soil of degraded meadows was lower than in the non degraded plots. However, the seed bank may buffer degradation to some extent since the degradation of aboveground vegetation was faster than impoverishment of seed bank. Consequently, seed rain and seed bank of degraded meadows still contained typical mesic meadow species in similar proportions as non-degraded meadows. This indicates that seed rain and seed bank may contribute to the restoration of degraded meadows after the removal of expansive species from the aboveground vegetation.

  • 52.
    Ruehl, A. T.
    et al.
    Univ Giessen, Inst Landscape Ecol & Resource Management, Heinrich Buff Ring 26-32, D-35392 Giessen, Germany..
    Eckstein, R. L.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Univ Giessen, Inst Landscape Ecol & Resource Management, Heinrich Buff Ring 26-32, D-35392 Giessen, Germany.
    Otte, A.
    Univ Giessen, Inst Landscape Ecol & Resource Management, Heinrich Buff Ring 26-32, D-35392 Giessen, Germany..
    Donath, T. W.
    Univ Kiel, Dept Landscape Ecol, Inst Nat Resource Conservat, Kiel, Germany..
    Distinct germination response of endangered and common arable weeds to reduced water potential2016In: Plant Biology, ISSN 1435-8603, E-ISSN 1438-8677, Vol. 18, p. 83-90Article in journal (Refereed)
    Abstract [en]

    Arable weeds are one of the most endangered species groups in Europe. Modern agriculture and intensive land-use management are the main causes of their dramatic decline. However, besides the changes in land use, climate change may further challenge the adaptability of arable weeds. Therefore, we investigated the response pattern of arable weeds to different water potential and temperature regimes during the phase of germination. We expected that endangered arable weeds would be more sensitive to differences in water availability and temperature than common arable weeds. To this end, we set up a climate chamber experiment where we exposed seeds of five familial pairs of common and endangered arable weed species to different temperatures (5/15, 10/20 degrees C) and water potentials (0.0 to -1.2 MPa). The results revealed a significant relationship between the reaction of arable weed species to water availability and their Red List status. The effects of reduced water availability on total germination, mean germination time and synchrony were significantly stronger in endangered than in common arable weeds. Therefore, global climate change may present a further threat to the survival of endangered arable weed species.

  • 53.
    Ruehl, A. Theresa
    et al.
    Univ Giessen, Inst Landscape Ecol & Resource Management, D-35392 Giessen, Germany..
    Donath, Tobias W.
    Univ Kiel, Inst Nat Resource Conservat, Dept Landscape Ecol, Olshaussenstr 40, D-24118 Kiel, Germany..
    Otte, Annette
    Univ Giessen, Inst Landscape Ecol & Resource Management, D-35392 Giessen, Germany..
    Eckstein, R. Lutz
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Impacts of short-term germination delay on fitness of the annual weed Agrostemma githago (L.)2016In: Seed Science Research, ISSN 0960-2585, E-ISSN 1475-2735, Vol. 26, no 2, p. 93-100Article in journal (Refereed)
    Abstract [en]

    Time of seedling emergence is an important step in the life cycle of annual plants because it may determine subsequent performance and success. Timing of emergence is especially critical to plant performance in habitats like arable fields which are subject to frequent disturbances. Within-season variation in timing of germination in the range of only a few days is typical for many arable weeds. However, since it is unclear whether such small deviations in germination date translate into fitness differences in the course of the life cycle, the aim of this paper was to quantify the effects of short germination delays on plant performance. We conducted two generalized randomized block experiments in an unheated greenhouse to study the impact of delayed germination (1, 2, 3 and 7 d) with and without competition, respectively, on the fitness of the arable weed species Agrostemma githago (L.). We expected that delayed germination significantly reduces fitness in terms of several life-history traits, and that the decrease of fitness is higher in the presence of competition. Under realistic conditions with competition through barley, Agrostemma plants with delayed germination of 7 d produced 54% fewer shoots, 57% less biomass, 52% fewer flowers, 36% lighter seeds and were 23% shorter as compared to control plants without delayed germination. Without additional stress through competition with barley this pattern was less pronounced. Thus, in the situation of interspecific competition, early emerging seedlings have biologically significant fitness advantages over later emerging seedlings of the same species.

  • 54. Ruehl, A. Theresa
    et al.
    Eckstein, Rolf Lutz
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences. Justus Liebig University Giessen, Germany.
    Otte, Annette
    Donath, Tobias W.
    Future challenge for endangered arable weed species facing global warming: Low temperature optima and narrow moisture requirements2015In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 182, p. 262-269Article in journal (Refereed)
    Abstract [en]

    As a result of the intensification of agriculture in Central Europe, many arable weed species have declined. Global climate change may further challenge the adaptability of arable weeds since plants may be more often subjected to higher temperatures and lower soil moisture during the germination period.

    A climate chamber experiment analysed the response of four familial pairs of common and endangered arable weeds from Germany. To this end we used a large range of temperatures and water potentials to assess specific traits defining their germination requirements. Using a simple response surface approach, we predicted germination response under three climate change scenarios.Results supported our expectation that endangered species, owing to their narrow germination requirements, may be more negatively affected by global warming than common species. Endangered species germinated significantly less than the common arable weeds, except at very low temperatures (3 °C and 5 °C). The preference of endangered arable weed species for low germination temperatures was confirmed by their low optimal germination temperature (15.8 °C ± 0.4). In contrast, common species germinated at significant higher temperatures (optimal temperature 18.4 °C ± 0.2), had a significantly wider range of germination temperature (endangered: 24 °C ± 3.5, common: 31 °C ± 0.5) and were also more flexible towards changes in water potential.Calculations based on response surfaces for three climate change scenarios indicated that endangered arable weed species may benefit less from climate warming than common species.

  • 55.
    Ruprecht, Eszter
    et al.
    Romania.
    Donath, Tobias W.
    Justus Liebig University Giessen, Germany.
    Otte, Annette
    Justus-Liebig-University Giessen, Germany.
    Eckstein, Rolf Lutz
    Justus-Liebig-University Giessen, Germany.
    Chemical effects of a dominant grass on seed germination of four familial pairs of dry grassland species2008In: Seed Science Research, ISSN 0960-2585, E-ISSN 1475-2735, Vol. 18, no 4, p. 239-248Article in journal (Refereed)
    Abstract [en]

    Community composition and ecosystem processes during succession may be driven partly by traits of plant species that attain dominance. Here, we addressed the hypothesis that Stipa pulcherrima, the dominant grass of abandoned continental grasslands, controls seedling recruitment of co-occurring species through chemical effects of its litter. Eight species with successful and unsuccessful recruitment under field conditions were selected (four familial pairs) to study experimentally the effects of leaf leachate under four temperature regimes. Since fungi developed in leachate-treated Petri dishes, in another experiment seeds were surface sterilized to remove confounding effects of fungi on recruitment. Leachate affected various stages of seedling recruitment: it significantly reduced seed germination (by 33-94%) and radicle elongation, and it delayed germination of seedlings of all species. In two families, species with unsuccessful field recruitment were more negatively affected than the successful ones. In a third family, the species with successful recruitment was more negatively affected, and in the fourth there were no differences. Similar germination responses after exclusion of fungi through seed-surface sterilization suggested that leachate was responsible for the observed effects on recruitment. Besides other traits and physical/microclimatic effects of accumulating litter, S. pulcherrima influences plant community dynamics and may potentially affect ecosystem processes through its secondary compounds.

  • 56.
    Ruprecht, Eszter
    et al.
    Romania.
    Enyedi, Marton Z.
    Romania.
    Eckstein, Rolf Lutz
    Justus-Liebig-University Giessen, Germany.
    Donath, Tobias W.
    Justus-Liebig-University Giessen, Germany.
    Restorative removal of plant litter and vegetation 40 years after abandonment enhances re-emergence of steppe grassland vegetation2010In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 143, no 2, p. 449-456Article in journal (Refereed)
    Abstract [en]

    The accumulation of biomass and of dead plant remains is a direct consequence of grassland abandonment. Litter can occupy potential microsites for seed germination and seedling establishment, and thus decrease species diversity in the long-term. This effect can be more accentuated in dry grassland of open structure where species are adapted to excessive light and bare surfaces during the recruitment phase. We conducted a field experiment with litter removal alone or in combination with vegetation cutting and studied germination and seedling survival during 2 years in two abandoned steppe sites. With our experimental treatments we intended to create microsites and to activate the seed bank, with the aim to enhance recruitment of dry-grassland species; potentially also those already absent from the established vegetation. Our results show, that while both treatments significantly increased recruitment by enhancing seed germination in the first year of the study, only litter removal combined with vegetation cutting significantly promoted seedling survival during both years. Our experiment demonstrated that even after 40 years of abandonment the applied measures favoured the re-emergence of target species that were very rare or absent from the above-ground vegetation of continental steppe-like grassland. Thus, management prescriptions which comprise removal of dead and even living biomass, such as mowing or grazing, are considered beneficial for this habitat type of high nature conservation priority. (C) 2009 Elsevier Ltd. All rights reserved.

  • 57.
    Schmiede, Ralf
    et al.
    Justus-Liebig-University, Giessen, Germany.
    Ruprecht, Eszter
    Babeş-Bolyai University, Romania.
    Eckstein, Rolf Lutz
    Justus-Liebig-University, Giessen, Germany.
    Otte, Annette
    Justus-Liebig University, Giessen, Germany.
    Donath, Tobias W.
    Justus-Liebig-University, Giessen, Germany.
    Establishment of rare flood meadow species by plant material transfer: Experimental tests of threshold amounts and the effect of sowing position2013In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 159, p. 222-229Article in journal (Refereed)
    Abstract [en]

    The transfer of freshly cut seed-containing plant material is a widely applied method to re-establish grassland of high biodiversity. Still, the amount of plant material applied varies greatly across restoration projects. Therefore, we set up a two-year common garden experiment where we assessed the effect of plant material amount (0, 400, 800, 1600, 3200 g m2 and relative seed position (on top and beneath a litter layer) on seedling establishment, seedling fate and seedling fitness of eight target species for restoration of alluvial meadows. Most seedlings (85.6%) emerged within the first year. Cumulative seedling emergence and final seedling establishment across all species were highest on control plots and low litter plots but were very low or failed completely, at 1600 and 3200 g m2, respectively. In general, large-seeded species were significantly more successful than smaller seeded species. Relative seed position had only a small impact on seedling emergence and establishment but was decisive for seedling survival at high litter quantities. Across all species, seedlings that died had a significantly lower relative height than surviving seedlings. Interestingly, co-occurring resident grassland vegetation had a neutral rather than negative impact on the response variables. Our results suggest an upper threshold of 1000 g m2 for the amount of plant material applied in grassland restoration, since higher amounts will inhibit seedling establishment. The prompt emergence of most seedlings during the first vegetation period highlights the importance of creating optimal conditions for seedling establishment already in the early phase of vegetation development on restoration sites.

  • 58.
    Schulz, Benjamin
    et al.
    Justus Liebig University Giessen, Germany.
    Durka, Walter
    Helmholtz Centre for Environmental Research-UFZ, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Germany..
    Danihelka, Jiri
    Masaryk University, Czech Republic; The Czech Academy of Sciences, Czech Republic..
    Eckstein, Rolf Lutz
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Differential role of a persistent seed bank for genetic variation in early vs. late successional stages2018In: PLoS ONE, E-ISSN 1932-6203, Vol. 13, no 12, article id e0209840Article in journal (Refereed)
    Abstract [en]

    Persistent seed banks are predicted to have an important impact on population genetic processes by increasing effective population size and storing past genetic diversity. Accordingly, persistent seed banks may buffer genetic effects of disturbance, fragmentation and/or selection. However, empirical studies surveying the relationship between aboveground and seed bank genetics under changing environments are scarce. Here, we compared genetic variation of aboveground and seed bank cohorts in 15 populations of the partially cleistogamous Viola elatior in two contrasting early and late successional habitats characterized by strong differences in light-availability and declining population size. Using AFLP markers, we found significantly higher aboveground than seed bank genetic diversity in early successional meadow but not in late successional woodland habitats. Moreover, individually, three of eight woodland populations even showed higher seed bank than aboveground diversity. Genetic differentiation among populations was very strong ((ST) = 0.8), but overall no significant differentiation could be detected between above ground and seed bank cohorts. Small scale spatial genetic structure was generally pronounced but was much stronger in meadow (Sp-statistic: aboveground: 0.60, seed bank: 0.32) than in woodland habitats (aboveground: 0.11; seed bank: 0.03). Our findings indicate that relative seed bank diversity (i.e. compared to aboveground diversity) increases with ongoing succession and despite decreasing population size. As corroborated by markedly lower small-scale genetic structure in late successional habitats, we suggest that the observed changes in relative seed bank diversity are driven by an increase of outcrossing rates. Persistent seed banks in Viola elatior hence will counteract effects of drift and selection, and assure a higher chance for the species' long term persistence, particularly maintaining genetic variation in declining populations of late successional habitats and thus enhancing success rates of population recovery after disturbance events.

  • 59.
    Schulz, Benjamin
    et al.
    Justus-Liebig-University, Giessen, Germany.
    Eckstein, Rolf Lutz
    Justus-Liebig-University, Giessen, Germany.
    Durka, Walter
    Justus-Liebig-University, Giessen, Germany.
    Epigenetic variation reflects dynamic habitat conditions in a rare floodplain herb2014In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 23, no 14, p. 3523-3537Article in journal (Refereed)
    Abstract [en]

    Variation of DNA methylation is thought to play an important role for rapid adjustments of plant populations to dynamic environmental conditions, thus compensating for the relatively slow response time of genetic adaptations. However, genetic and epigenetic variation of wild plant populations has not yet been directly compared in fast changing environments. Here, we surveyed populations of Viola elatior from two adjacent habitat types along a successional gradient characterized by strong differences in light availability. Using amplified fragment length polymorphisms (AFLP) and methylation-sensitive amplification polymorphisms (MSAP) analyses, we found relatively low levels of genetic (H-gen' = 0.19) and epigenetic (H-epi' = 0.23) diversity and high genetic (phi(ST) = 0.72) and epigenetic (phi(ST) = 0.51) population differentiation. Diversity and differentiation were significantly correlated, suggesting that epigenetic variation partly depends on the same driving forces as genetic variation. Correlation-based genome scans detected comparable levels of genetic (17.0%) and epigenetic (14.2%) outlier markers associated with site specific light availability. However, as revealed by separate differentiation-based genome scans for AFLP, only few genetic markers seemed to be actually under positive selection (0-4.5%). Moreover, principal coordinates analyses and Mantel tests showed that overall epigenetic variation was more closely related to habitat conditions, indicating that environmentally induced methylation changes may lead to convergence of populations experiencing similar habitat conditions and thus may play a major role for the transient and/or heritable adjustment to changing environments. Additionally, using a new MSAP-scoring approach, we found that mainly the unmethylated (phi(ST) = 0.60) and CG-methylated states (phi(ST) = 0.46) of epiloci contributed to population differentiation and putative habitat-related adaptation, whereas CHG-hemimethylated states (phi(ST) = 0.21) only played a marginal role.

  • 60.
    Schulz, Benjamin
    et al.
    Justus-Liebig-University Giessen, Germany.
    Eckstein, Rolf Lutz
    Justus-Liebig-University Giessen, Germany.
    Durka, Walter
    Helmholtz Centre for Environmental Research.
    Scoring and analysis of methylation-sensitive amplification polymorphisms for epigenetic population studies2013In: Molecular Ecology Resources, ISSN 1755-098X, E-ISSN 1755-0998, Vol. 13, no 4, p. 642-653Article in journal (Refereed)
    Abstract [en]

    DNA methylation is an important, heritable epigenetic modification in most eukaryotic organisms that is connected with numerous biological processes. To study the impact of natural epigenetic variation in an ecological or evolutionary context, epigenetic studies are increasingly using methylation-sensitive amplification polymorphism (MSAP) for surveys at the population or species level. However, no consensus exists on how to interpret and score the multistate information obtained from the MSAP banding patterns. Here, we review the previously used scoring approaches for population epigenetic studies and develop new alternatives. To assess effects of the different approaches on parameters of epigenetic diversity and differentiation, we applied eight scoring schemes to a case study of three populations of the plant species Viola elatior. For a total number of 168 detected polymorphic MSAP fragments, the number of ultimately scored polymorphic epiloci ranged between 78 and 286 depending on the particular scoring scheme. Both, estimates of epigenetic diversity and differentiation varied strongly between scoring approaches. However, linear regression and PCoA revealed qualitatively similar patterns, suggesting that the scoring approaches are largely consistent. For single-locus analyses of MSAP data, for example the search for loci under selection, we advocate a new scoring approach that separately takes into account different methylation types and thus seems appropriate for drawing more detailed conclusions in ecological or evolutionary contexts. An R script (MSAP_score.r) for scoring and basic data analysis is provided.

  • 61.
    Shakeri, Zahed
    et al.
    Iran.
    Mohadjer, Mohammad Reza Marvie
    Iran.
    Simberloff, Daniel
    USA.
    Etemad, Vahid
    Iran.
    Assadi, Mostafa
    Iran.
    Donath, Tobias W.
    Germany.
    Otte, Annette
    Germany.
    Eckstein, Rolf Lutz
    Germany.
    Plant community composition and disturbance in Caspian Fagus orientalis forests: which are the main driving factors?2012In: Phytocoenologia, ISSN 0340-269X, Vol. 41, no 4, p. 247-263Article in journal (Refereed)
    Abstract [en]

    The oriental beech forests along the southern Caspian Sea shores of Iran are characterized by high biodiversity and high ecological value. However, there is little information concerning factors governing community composition and the presence and abundance of invasive plants. In the present study we aimed to evaluate the main drivers of community composition, diversity, and establishment of invasive plants in disturbed and undisturbed Fagus orientalis communities. We sampled 104 vegetation releves in undisturbed and disturbed sites of the "Kheiroud Investigation Forest" in northern Iran and collected data on a large number of environmental variables concerning soil properties, light conditions, and topography. Data analysis consisted of a forward selection of significant explanatory variables followed by partial CCA analyses. Additionally, we carried out indicator species analysis of groups of releves affected by different disturbance types and analyzed effects of disturbance on species richness, diversity, and evenness using general linear models. CCA results showed that disturbance, soil properties, light conditions and elevation explained 22.6% of the total variation in floristic composition. Gap and gap + grazing were the most important disturbance types affecting community composition. Disturbance had significant but rather weak effects on species richness, evenness, and the Shannon index. The most obvious effect of disturbance was on species composition, as revealed by significant groups of indicator species for different disturbance types. Most of the indicator species in grazed sites were unpalatable, poisonous, and creeping species, which are avoided by cattle. Grazing led to decreased abundance of indicator species and species characteristic of old-growth Fagus forests. The most intensive disturbance type "harvesting + gap + grazing" was associated with invasion by native vascular plant species not typically found in beech forests (apophytes).

  • 62.
    Voss, Nicole
    et al.
    Justus-Liebig-University Giessen, Germany.
    Eckstein, Rolf Lutz
    Justus-Liebig-University Giessen, Germany.
    Durka, Walter
    UFZ, Halle, Germany.
    Range expansion of a selfing polyploid plant despite widespread genetic uniformity2012In: Annals of Botany, ISSN 0305-7364, E-ISSN 1095-8290, Vol. 110, no 3, p. 585-593Article in journal (Refereed)
    Abstract [en]

    Ongoing and previous range expansions have a strong influence on population genetic structure of plants. In turn, genetic variation in the new range may affect the population dynamics and the expansion process. The annual Ceratocapnos claviculata (Papaveraceae) has expanded its Atlantic European range in recent decades towards the north and east. Patterns of genetic diversity were investigated across the native range to assess current population structure and phylogeographical patterns. A test was then made as to whether genetic diversity is reduced in the neophytic range and an attempt was made to identify source regions of the expansion. Samples were taken from 55 populations in the native and 34 populations in the neophytic range (Sweden, north-east Germany). Using amplified fragment length polymorphism markers an analysis was made of genetic variation and population structure (Bayesian statistical modelling) and population differentiation was quantified. Pollen/ovule ratio was analysed as a proxy for the breeding system. Genetic diversity at population level was very low (mean H-e 0004) and two multilocus genotypes dominated large parts of the new range. Population differentiation was strong (F-ST 0812). These results and a low pollen/ovule ratio are consistent with an autogamous breeding system. Genetic variation decreased from the native to the neophytic range. Within the native range, H-e decreased towards the north-east, whereas population size increased. According to the Bayesian cluster analysis, the putative source regions of the neophytic range are situated in north-west Germany and adjacent regions. Ceratocapnos claviculata shows a cline of genetic variation due to postglacial recolonization from putative Pleistocene refugia in south-west Europe. Nevertheless, the species has expanded successfully during the past 40 years to southern Sweden and north-east Germany where it occurs as an opportunistic neophyte. Recent expansion was mainly human-mediated by single long-distance diaspore transport and was facilitated by habitat modification.

  • 63. Voss, Nicole
    et al.
    Simmering, Dietmar
    Peppler-Lisbach, Cord
    Carl von Ossietzky University Oldenburg.
    Durka, Walter
    Helmholtz Centre for Environmental Research, Halle, Germany.
    Eckstein, Rolf Lutz
    Justus-Liebig-University Giessen, Germany.
    Vegetation databases as a tool to analyse factors affecting the range expansion of the forest understory herb Ceratocapnos claviculata2011In: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 22, no 4, p. 726-740Article in journal (Refereed)
    Abstract [en]

    Question: The eu-atlantic forest herb Ceratocapnos claviculata showed a recent increase in frequency within its native range and an eastward and northward range expansion in Central Europe. To gain deeper understanding of factors affecting the range expansion of the species, we analyzed vegetation releves at three different scales and asked the following questions: As the species occurs in a wide range of vegetation types, is variation in community composition across the entire range related to climatic environmental zones and tree cover? Are there differences in species composition and habitat characteristics between the native range and the two invaded regions (S Sweden and NE Germany)? Did community composition and habitat characteristics within the native range (The Netherlands) change between 'before 1970' and '1990 to 2006'? Location: W, C and N Europe. Methods: We analysed vegetation-plot data with C. claviculata from various databases and own surveys using partial CCA, partial DCA, Indicator Species Analysis, MANCOVA and multiple regression. Results: Using vegetation plots from the entire distribution range, climatic environmental zones explained 68.9% of the total canonical Eigenvalue. Differences in floristic composition and habitat characteristics between the two invaded regions were as large as between native and invaded range sites. However, releves from the invaded range were generally characterized by anthropogenic disturbance. Accordingly, abundance of C. claviculata was positively linked to silvicultural intensity. New releves from 1990 to 2006 were characterized by higher Ellenberg nutrient indicator values, lower species diversity, higher proportions of neophytic and hemerobic species and showed a lower cover of the study species than old releves from before 1970. Conclusions: Across the range of C. claviculata, climatic environmental zones determine vegetation composition. Accordingly, the species is characterized by a broad macroclimatic amplitude. Vegetation composition and structure differ significantly between the two regions of the new range. Thus, the species has successfully established under various biotic and abiotic environmental conditions. Beyond potential positive effects of soil eutrophication and mild winters, anthropogenic impact may directly facilitate seed dispersal and provide sites and resource conditions suitable for germination and establishment of C. claviculata, whereas a decrease of forest management may constrain the species.

  • 64.
    Voss, Nicole
    et al.
    Justus-Liebig-University, Giessen, Germany.
    Welk, Erik
    Martin Luther Univerity, Halle, Germany.
    Durka, Walter
    UFZ, Halle, Germany.
    Eckstein, Rolf Lutz
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences. Justus-Liebig-University Giessen, Germany.
    Biological flora of Central Europe: Ceratocapnos claviculata (L.) Liden2012In: Perspectives in plant ecology, evolution and systematics, ISSN 1433-8319, E-ISSN 1618-0437, Vol. 14, no 1, p. 61-77Article in journal (Refereed)
    Abstract [en]

    The eu-oceanic therophytic woodland herb Ceratocapnos claviculata has been expanding north- and eastwards into north temperate and subcontinental regions during the past decades. The rapid range expansion of the species may be an example of a species which is strongly profiting from global change. Against this background, in the present paper we review the taxonomy, morphology, distribution, habitat requirements, life cycle and biology of the species. (C) 2011 Elsevier GmbH. All rights reserved.

  • 65.
    Winter, Silvia
    et al.
    University of Natural Resources and Life Sciences Vienna, Austria.
    Jung, Linda S.
    Justus-Liebig-University, Giessen, Germany.
    Eckstein, Rolf Lutz
    Justus-Liebig-University, Giessen, Germany.
    Otte, Annette
    Justus-Liebig-University, Giessen, Germany.
    Donath, Tobias W.
    Justus-Liebig-University, Giessen, Germany.
    Kriechbaum, Monika
    University of Natural Resources and Life Sciences Vienna, Austria.
    Control of the toxic plant Colchicum autumnale in semi- natural grasslands: Effects of cutting treatments on demography and diversity2014In: Journal of Applied Ecology, ISSN 0021-8901, E-ISSN 1365-2664, Vol. 51, no 2, p. 524-533Article in journal (Refereed)
    Abstract [en]

    Semi-natural grasslands are important habitats for the conservation of biodiversity in Europe. High population densities of toxic Colchicum autumnale in these grasslands may cause problems for livestock and the marketing of hay. Consequently, farmers may either intensify grassland management to reduce C. autumnale in the fodder or abandon the land; both practices will lead to a loss of biodiversity. Previous studies suggesting early cutting to control C. autumnale did not consider population dynamics and the effects on plant diversity. We conducted a four-year experiment in six regions within Austria and Germany, applying five cutting treatments in 16 C. autumnale populations to test the effects of cutting date and frequency on C. autumnale and co-occurring vegetation. Demographic data were evaluated with matrix population models, life-table response experiment (LTRE), anova and manova. Vegetation data were analysed with multiresponse permutation procedures (MRPP), anova and manova. Population growth rate was significantly reduced in plots cut in early and late May compared to plots cut in June (control). Plants cut in late April or early May showed the lowest survival probability. Significantly fewer large vegetative plants developed capsules in the following year when cut in early or late May. LTRE analysis showed that differences in the population growth rate between the control and early cut treatments were mainly the result of a reduced survival and growth and an increased retrogression to smaller stages. Multiresponse permutation procedures revealed no differences in vegetation composition between treatments except for one site in 2011. There were no differences in Shannon index, evenness or species turnover rate within any year. Synthesis and applications. The greatest reduction in vitality of Colchicum autumnale was observed in grasslands cut in late April or early May. After three years of early cutting, no reduction in plant species diversity was observed. The second cut should be postponed to July to enable seed shed of plants. Grassland management decisions to control toxic C. autumnale must be made in close cooperation with nature conservation authorities to consider site characteristics and requirements of endangered species. The greatest reduction in vitality of Colchicum autumnale was observed in grasslands cut in late April or early May. After three years of early cutting, no reduction in plant species diversity was observed. The second cut should be postponed to July to enable seed shed of plants. Grassland management decisions to control toxic C. autumnale must be made in close cooperation with nature conservation authorities to consider site characteristics and requirements of endangered species.

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