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  • 1.
    Burmeier, Sandra
    et al.
    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.
    Spatially-restricted plant material application creates colonization initials for flood-meadow restoration2011Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 144, nr 1, s. 212-219Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Plant material transfer is a well-established technique for overcoming dispersal limitation during grassland restoration. As restoration sites are frequently more abundant than donor sites, the plant material is often applied as patches or strips, with the assumption that these will act as colonization initials from which transferred species will spread and eventually cover the entire sites. Our aim was to test this assumption and to evaluate whether it is feasible to restore entire sites by spatially-restricted plant material application in a flood-meadow ecosystem. We established transverse transects consisting of eight 2 x 2 m plots on five plant material strips 7-8 years after plant material application. We monitored the above-ground vegetation development, analyzed the seed rain and determined the composition of the soil seed bank, i.e. we compared three different components of the emerging flood-meadow community. Transferred species were present in all three community components studied, and 88.6% of the 79 species we found in total had already spread from the plant material strips and colonized their surroundings. Detected dispersal distances differed between community components, and the share of colonizers was highest for the above-ground vegetation and lowest for the soil seed bank. We conclude that plant material transfer is a suitable technique for restoring flood-meadows as transferred species not only establish on the sites supplied with plant material, but also colonize their surroundings. (C) 2010 Elsevier Ltd. All rights reserved.

  • 2. Ruehl, A. Theresa
    et al.
    Eckstein, Rolf Lutz
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper. 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 requirements2015Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 182, s. 262-269Artikel i tidskrift (Refereegranskat)
    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.

  • 3.
    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 vegetation2010Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 143, nr 2, s. 449-456Artikel i tidskrift (Refereegranskat)
    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.

  • 4.
    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 position2013Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 159, s. 222-229Artikel i tidskrift (Refereegranskat)
    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.

  • 5.
    Washington, Haydn
    et al.
    Kensington Campus, Australia.
    Chapron, Guillaume
    Swedish University of Agricultural Sciences, Sweden.
    Kopnina, Helen
    International Business Management Studies, the Netherlands.
    Curry, Patrick
    The Ecological Citizen, United Kingdom.
    Gray, Joe
    University of London, United Kingdom.
    Piccolo, John
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Foregrounding ecojustice in conservation2018Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 228, s. 367-374Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Justice for nature remains a confused term. In recent decades justice has predominantly been limited to humanity, with a strong focus on social justice, and its spin-off – environmental justice for people. We first examine the formal rationale for ecocentrism and ecological ethics, as this underpins attitudes towards justice for nature, and show how justice for nature has been affected by concerns about dualisms and by strong anthropocentric bias. We next consider the traditional meaning of social justice, alongside the recent move by some scholars to push justice for nature into social justice, effectively weakening any move to place ecojustice centre-stage. This, we argue, is both unethical and doomed to failure as a strategy to protect life on Earth. The dominant meaning of ‘environmental justice’ – in essence, justice for humans in regard to environmental issues – is also explored. We next discuss what ecological justice (ecojustice) is, and how academia has ignored it for many decades. The charge of ecojustice being ‘antihuman’ is refuted. We argue that distributive justice can also apply to nature, including an ethic of bio-proportionality, and also consider how to reconcile social justice and ecojustice, arguing that ecojustice must now be foregrounded to ensure effective conservation. After suggesting a ‘Framework for implementing ecojustice’ for conservation practitioners, we conclude by urging academia to foreground ecojustice. © 2018

  • 6.
    Österling, Martin
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Test and application of a non-destructive photo-method investigating the parasitic stage of the threatened mussel Margaritifera margaritifera on its host fish E. Salmo trutta2011Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 144, nr 12, s. 2984-2990Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The objective was to test the application of a novel, non-destructive photo-method estimating the larval encystment of one of the highly threatened unionid mussels, the freshwater pearl mussel (Margaritifera margaritifera) on the gills of its host fish, brown trout (Salmo trutta). There were significant correlations between the encystment intensity based on microscope counts and using the new photo-method for both young-of-the-year and older brown trout just after the encystment in October 2007 and just before larval release from the host fish in June 2008. The mean encystment intensity based on the two methods did not differ from each other for the two age classes of trout when based on comparisons including all individuals. An aquaria experiment showed that there were no differences in survival or growth between fish subjected to the treatments: photo-method and individual marking, photo-method and a control. When applied to encystment in single streams, there were significant correlations between the mean encystment intensity in each stream based on the methods for both trout age classes. Therefore, it may be possible to get reliable estimation of the encystment rates without injuring the mussel or the host fish, which may also be used in restoration and cultivation work. Furthermore, the larvae of M. margaritifera are among the smallest of all the worldwide-distributed, threatened unionid mussel species. The photomethod may therefore also be used for other mussel species with larger larvae, as they are more easily recognized on photos. Therefore, it may now be possible to investigate every life stage of unionid species without using harmful methods at all.

  • 7.
    Österling, Martin
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Greenberg, Larry
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Arvidsson, Björn L
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Relationship of biotic and abiotic factors to recruitment patterns in Margaritifera margaritifera2008Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 141, nr 5, s. 1365-1370Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigated relationships of biotic and abiotic factors to recruitment patterns of the endangered freshwater pearl mussel (Margaritifera margaritifera) in 10 Swedish streams. We found that the maximum proportion of gravid mussels did not differ between streams with and without recent recruitment. Moreover, the mean glochidial load on trout (Salmo trutta), which was positively related to adult mussel density, did not differ significantly between these stream types. Thus, the larval stages of the freshwater pearl mussel were not related to recruitment failure. Instead, recruitment is probably hindered at the next stage in the life history of the mussels, the benthic stage, and may be related to sedimentation as turbidity was four times greater in streams lacking recent recruitment than in streams with recent recruitment. Furthermore, we found that juvenile mussel density was positively related to the number of glochidial infections per stream area in streams with ongoing recruitment, indicating that successful recruitment in these streams may depend on both mussel and trout density. Future research should thus examine biotic interactions between mussels and trout as well as the effects of sedimentation on benthic-living mussels.

  • 8.
    Österling, Martin
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper.
    Soderberg, Hakan
    Cty Adm Board Vasternorrland, S-87186 Harnosand, Sweden..
    Sea-trout habitat fragmentation affects threatened freshwater pearl mussel2015Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 186, s. 197-203Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Habitat fragmentation is a major reason for the decline and extinction of migratory species. Many host populations for parasites are partly migratory, consisting of both migratory and resident individuals, and we asked the question whether these two subpopulations differ in parasite susceptibility. If so, barriers intercepting migration may change the parasite encystment rate and recruitment. We used the River Ljungan, Sweden, as study system, where eight hydroelectric power plants hinder access of sea-migrating trout to most tributaries. We compared the encystment of the threatened freshwater pearl mussel (Margaritifera margaritifera) larvae on sympatric tributary-resident brown trout and sea-migrating trout (Salmo trutta) as hosts for their parasitic larvae. We also compared eighteen tributary-resident brown trout populations with the sea-migrating trout as hosts for mussel larvae. Encystment decreased faster over time on the tributary-resident trout than on the sea-migrating trout. Encystment was therefore higher on the sea-migrating trout compared to the tributary-resident trout at the time of excystment of the larvae. Growth of encysted mussel larvae was higher on the sea-migrating trout than on the tributary-resident trout. The natural density of the tributary-resident trout populations was lower than that of the sea-migrating trout in the autumn, when the mussels infest the fish, and in early summer, just before the excystment of juvenile mussels from the fish. Estimations of total numbers of encysted mussel larvae per unit stream area were higher on the sea-migrating trout than the tributary-resident trout in the autumn and in the spring at the time of juvenile mussel excystment. The higher mussel larval growth and the higher encystment on the sea-migrating trout imply that even seemingly healthy tributary mussel populations are reduced because of the habitat fragmentation. As sea-migrating trout are threatened or extinct in many rivers, fragmentation may be a large-scale problem, not only for sea-migrating populations, but also indirectly for highly threatened mussel populations. Restoration activities should primarily focus on creating free pathways for original host fish populations instead of sustaining them by supplementary stocking. (C) 2015 Elsevier Ltd. All rights reserved.

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