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Wet meadow restoration in Western Europe: A quantitative assessment of the effectiveness of several techniques

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Abstract

Techniques such as rewetting, topsoil removal, diaspore transfer or combinations of these are increasingly applied in fen meadow and flood meadow restoration in Western Europe. In this paper, we present a quantitative assessment of the effectiveness of the commonly used meadow restoration methods. We use the change in ‘saturation index’ to evaluate the degree of success. The index reflects the completeness of restored communities in comparison to regional target communities. Meadow restoration has limited success in most cases, with an average increase in species richness below 10% of the regional species pool. Restoration success was partly determinated by the starting situation. The more species-rich the starting situation, the higher the saturation index after restoration but, at the same time, the smaller the increase in the number of target species due to restoration. Top soil removal and diaspore transfer were found to contribute most to restoration success. A combination of top soil removal and diaspore transfer and a combination of all three techniques appeared to be the most effective measure and resulted in an increase in the saturation index of up to 16%. Rewetting alone had no measurable effect on restoration success.
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... In degradierten Mooren bildet die Wiederherstellung der hydrologischen Bedingungen die Grundvoraussetzung, um den Fortbestand des Ökosystems zu sichern und um eine Verbesserung des Ökosystemzustandes zu erreichen (SCHRAUTZER et al. 2013, JOOSTEN 2016a, KOTOWSKI et al. 2016. Daraus folgt, dass im ersten Schritt Maßnahmen wie beispielsweise der Verschluss von Entwässerungsgräben umgesetzt werden, um eine Wiedervernässung der degradierten Moorfläche zu erreichen (KLIMKOWSKA et al. 2007, KLIMKOWSKA et al. 2019. Letztendlich sollen die Renaturierungsmaßnahmen dazu beitragen, die biotische Ausstattung sowie die abiotischen Bedingungen der Projektflächen in einen naturnäheren Zustand zu versetzen ). ...
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... Die Ökosystemrenaturierung beschreibt einen Prozess "of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed" (SER 2004 (KLIMKOWSKA et al. 2007, BÉRUBÉ & ROCHEFORT 2018, KLIMKOWSKA et al. 2019, SALIMI et al. 2021). (verändert nach BRADSHAW 1987, KIEHL 2019. ...
Thesis
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Article
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Article
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Article
Full-text available
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Article
Full-text available
V prispevku sta predstavljeni prostorska analiza in modeliranje, ki smo ju uporabili za spremljanje dinamike in vzorca pojavljanja mokrotnih travnikov (Molinion caeruleae Koch 1926) v Prekmurju. Osnovne podatke o razširjenosti mokrotnih travnikov smo pridobili s terenskim delom, geomorfološke in socioekonomske dejavnike, ki pojasnjujejo njihovo razširjenost in dinamiko pa z obdelavo osnovnih prostorskih podatkov (digitalnega modela višin, analiza cestnega omrežja in vzorca poselitve, analiza izbranih krajinskih elementov). V nadaljevanju smo s pomočjo generaliziranega linearnega modela (GLM) ugotavljali vpliv opazovanih geomorfoloških in socio-ekonomskih podatkov na sedanjo razporeditev mokrotnih travnikov v krajini. Število mokrotnih travnikov se je na Goričkem močno zmanjšalo. Najpomembnejša dejavnika, ki vplivata na pojavljanje travnikov na opazovanem območju sta nadmorska višina in naklon terena. Največ mokrotnih travnikov najdemo med 250 in 300 metri nadmorske višine. Na slemenih gričev so ti habitati zaradi urbaniziranega prostora ne pojavljajo. Z naraščanjem nagiba (inklinacije) se povečuje tudi število mokrotnih travnikov. Na ravnini so takšni travniki zaradi intenzifikacije kmetijske rabe skorajda izginili, prav tako na vrhovih gričev, ki so pozidani s stanovanjskimi objekti ali drugače degradirani. Najbolj ogrožena območja mokrotnih travnikov najdemo na ravninskem (južnem) delu Goričkega ter ob meji z Madžarsko in Avstrijo.
... Untouched peatlands rightly served as a reference (e.g. Dijk et al. 2007;Klimkowska et al. 2007;Herold 2012). The biodiversity of rewetted, mown or grazed paludiculture fens should, however, not be compared with that of near-natural fens. ...
Article
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Peatlands in the European Union are largely drained for agriculture and emit 25% of the total agricultural greenhouse gas emissions. Drainage-based peatland use has also negative impacts on water quality, drinking water provision and biodiversity. Consequently, key EU environmental policy objectives include the rewetting of all drained peatlands as an essential nature-based solution. Rewetting of peatlands can be combined with site-adapted land use, so-called paludiculture. Paludiculture produces biomass from wet and rewetted peatlands under conditions that maintain the peat body, facilitate peat accumulation and can provide many of the ecosystem services associated with natural, undrained peatlands. The biomass can be used for a wide range of traditional and innovative food, feed, fibre and fuel products. Based on examples in Germany, we have analysed emerging paludiculture options for temperate Europe with respect to greenhouse gas fluxes, biodiversity and indicative business economics. Best estimates of site emission factors vary between 0 and 8 t CO 2 eq ha ⁻¹ y ⁻¹ . Suitability maps for four peatland-rich federal states (76% of total German peatland area) indicate that most of the drained, agriculturally used peatland area could be used for paludiculture, about one-third of the fen area for any paludiculture type. Fen-specific biodiversity benefits from rewetting and paludiculture, if compared to the drained state. Under favourable conditions, paludiculture can be economically viable, but costs and revenues vary considerably. Key recommendations for large-scale implementation are providing planning security by paludiculture spatial planning, establishing best practice sites and strengthening research into crops, water tables and management options.
... In grasslands, this persistence and dispersal filter correlates with the establishment of widespread and persistent wind dispersers such as common grasses (Werner et al., 2016), which may, once established, compromise the re-colonization potential of rare target species (Partzsch et al., 2018). Removal of the existing grass layer followed by the manual transfer of propagules of target species, for example by seed or hay transfer from a species-rich reference site, can be a meaningful tool to bypass colonization restrictions (Donath et al., 2007;Klimkowska et al., 2007;Pywell et al., 2007;Torok et al., 2011). ...
Article
Soil inoculation from plant species-rich into species-poor grasslands may enable the establishment of self-facilitating networks between microbes and vegetation, thereby steering ecosystem development. We conducted a three-year experiment that covered a wide range of post-agricultural grasslands to determine how succession is affected by the interactive effects of edaphic properties, grass layer removal and hay or soil fragment transfer from a late-successional donor grassland. Soil inoculation generally impacted community assembly of vegetation and fungi, but not of prokaryotes. Effects were strongest when preceded by removal of the grass layer, indicating the importance of priority effects and dispersal limitation. Inoculation enabled the establishment of putative rhizosphere-associated fungal taxa, particularly from the families Helotiaceae, Glomeraceae and Archaeorhizomycetaceae. Nonetheless, effect sizes were mostly small, as was overall resemblance of the receptor grasslands to the donor. Fungal communities were primarily shaped by environmental filters and only reached a high resemblance to the donor in nutrient-poor sites. Shifts in the vegetation were strongest in those grasslands where the mycobiome more closely resembled that of the donor. Soil inoculation generally facilitates colonization by target plant and fungal communities, where establishment success of the former can be predicted by the latter, but the final outcome of succession is environmentally determined.
Chapter
Referring to the manifold studies and the long-term experiences of the restoration of near-natural ecosystems and traditional land-use types, respectively, examples from all over the world are outlined. Additionally to rewilding as a progressive approach to nature conservation, letting nature take care of itself and enabling natural processes, particularly the restoration of heathland, agricultural grassland, savannas, agroforestry systems, silvopastoral systems, coppice forests, lakes, peatland, coastal mangroves, terraced and irrigation land-use systems is addressed. The unique features of these ecosystems and land-use systems, respectively, which are or could be embedded in traditional and multifunctional cultural landscapes encompass high biodiversity, agrobiodiversity, and agrodiversity, respectively, as well as the provision of manifold ecosystem and landscape services.
Chapter
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Chapter
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