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    Vegetation succession and habitat restoration in Dutch lichen-rich inland drift sands
    Ketner-Oostra, R. ; Aptroot, A. ; Jungerius, P.D. ; Sykora, K.V. - \ 2012
    Tuexenia 32 (2012). - ISSN 0722-494X - p. 245 - 268.
    campylopus-introflexus - netherlands
    Between 1996 and 2006 the vegetation succession in drift sands and in blown-out gravel-rich depressions, located in the nature reserve Hulshorsterzand in the central Netherlands, was studied. Within this Natura 2000 habitat (type 2330: inland dunes with o
    Effect van overstuiving op korstmosrijke duinen op Terschelling
    Ketner-Oostra, R. ; Sykora, K.V. - \ 2012
    De Levende Natuur 113 (2012)4. - ISSN 0024-1520 - p. 167 - 173.
    duingebieden - duinplanten - vegetatietypen - grassen - nederlandse waddeneilanden - friesland - duneland - duneland plants - vegetation types - grasses - dutch wadden islands - friesland
    De botanische verscheidenheid in kalkarme droge duinen wordt o.a. door korstmossen gevormd. Sinds de jaren 80 van de vorige eeuw zijn deze duinen in het Waddendistrict sterk veranderd door vergrassing met Helm en Zandzegge en vermossing met Grijs kronkelsteeltje. Kan overstuiving met vers zand deze uniformiteit doorbreken? Jarenlange monitoring van de vegetatie op Terschelling geeft hier het antwoord op.
    Effectgerichte maatregelen voor het herstel en beheer van stuifzanden
    Nijssen, M. ; Riksen, M.J.P.M. ; Sparrius, L. ; Bijlsma, R.J. ; Burg, A. van der; Dobben, H.F. van; Jungerius, P. ; Ketner-Oostra, R. ; Kooiman, A. ; Kuiters, L. ; Swaay, C. van; Turnhout, C. van; Waal, R. de - \ 2011
    Den Haag : Ministerie van EL&I, directie IFZ/bedrijfsuitgeverij (Rapport DKI nr. 2011/OBN144-DZ) - 293
    eolisch zand - ecologisch herstel - natuurbeheer - fauna - vegetatie - plantensuccessie - nederland - herstelbeheer - natura 2000 - aeolian sands - ecological restoration - nature management - fauna - vegetation - plant succession - netherlands - restoration management - natura 2000
    Onderzoek naar het functioneren van stuifzanden onder gewijzigde abiotische condities en naar beheer en herstel van klein- en grootschalige stuifzandlandschappen. Waarin bijdragen: Bosschap, Stichting Bargerveen, Radboud Universiteit, Universiteit Amsterdam, SOVON, Vlinderstichting, Alterra en Stichting Geomofologie en Landschap. Het is een vervolg op Preadvies stuifzanden (Bakker, 2003).
    Vegetation change in a lichen-rich inland drift sand area in the Netherlands
    Ketner-Oostra, R. ; Sykora, K.V. - \ 2008
    Phytocoenologia 38 (2008)4. - ISSN 0340-269X - p. 267 - 286.
    campylopus-introflexus - grassland - moss - invasion
    In this paper we compare the cryptogam vegetation in the Spergulo-Corynephoretum and Genisto-Callunetum in an inland drift-sand area in three periods (1968, 1993 and 2004). In the early period the lichen diversity in these plant communities appeared to be very high. The aspect was formed by Corynephorus canescens and Polytrichum piliferum. The highest numbers of lichen species are found in the S.-C. cladonietosum, irrespective of the period. In all years, variants of this subassociation are found, with many lichen species. In time pH decreases and organic matter, % total N and % total P increase by humus production. Cover sands having relatively high content of cations form a suitable substrate for lichens. Since the 1970s the neophytic moss Campylopus introflexus, a species adapted to acidic, nutrient-poor sand, has invaded the sand dunes. These changes have been attributed to the high aerial deposition of N in this central part of the Netherlands. In the more recent periods the actual lichen diversity did not really diminish, but the cover of lichen-rich plant communities was clearly reduced when encroaching mosses outgrew the lichens in all succession stages. However, when C. introflexus is less vital because of ageing, desiccation or burial under wind-blown sand, common humicole, aero-hygrophytic and even pioneer lichen species may locally establish on or between the moss cushions. The former succession series starting with P. piliferum and ending with lichen-rich Calluna heath (1968) has been partly replaced by one including C. introflexus (1993 and 2004). Process management is necessary to keep the sand blowing and hereby reduce the colonization by C. introflexus. Habitat restoration by small-scale management consisting of cutting down self-sown trees and removing the top soil has positively influenced lichen diversity and needs to be continued.
    Onderzoek naar effectgerichte maatregelen voor het herstel en beheer van stuifzanden
    Sparrius, L.B. ; Kooijman, A. ; Nijssen, M. ; Esselink, H. ; Burg, A. Van den; Riksen, M. ; Kuiters, A.T. ; Bijlsma, R.J. ; Waal, R.W. de; Dobben, H.F. van; Ketner-Oostra, R. ; Jongerius, P. ; Turnhout, C. van; Swaay, C. van - \ 2008
    Amsterdam, Nijmegen, Wageningen : Stichting Bargerveen, Universiteit van Amsterdam, Radboud Universiteit, Alterra, Wageningen Universiteit (Tweede tussenrapport, februari 2008 ) - 86 p.
    Succession in lichen-rich vegetation in coastal dunes between 1995 and 2005
    Ketner-Oostra, R. ; Sykora, K.V. - \ 2008
    Abhandlungen aus dem Westfälischen Museum für Naturkunde 70 (2008)3/4. - ISSN 0175-3495 - p. 125 - 142.
    Veranderingen van de mos- en licheenvegetatie in de droge duinen van Terschelling sinds 1970. II. Microklimaat
    Ketner-Oostra, R. - \ 2007
    Buxbaumiella 2007 (2007)79. - ISSN 0166-5405 - p. 14 - 22.
    Onderzoek voor de toepassing van effectgerichte maatregelen in het stuifzandlandschap van het Hulshorster Zand
    Jungerius, P.D. ; Ketner-Oostra, R. ; Acker, H. van den; Aptroot, A. ; Boer, P. ; Keizer, P.J. ; Koopmans, G. ; Noordijk, J. ; Raaijmakers, H. ; Riksen, M. ; Struijk, R. ; Verkerk, L. - \ 2006
    Ede : Stichting Geomorfologie & Landschap
    Notitie over het uitplanten van korstmossen
    Geraerdts, W.H.J.M. ; Ketner-Oostra, H.G.M. - \ 2006
    Buxbaumiella 75 (2006). - ISSN 0166-5405 - p. 6 - 8.
    korstmossen - habitats - tuinen - lichens - habitats - gardens
    In de voormalige tuin van Wim Geraedts (Wijchen, Gelderland) blijkt het uitplanten van korstmossen een sukses te zijn. Het gaat om enkele Cladonia-soorten, een Cladina- en twee Peltigera-soorten. Het biotoop waarin ze uitgezet zijn, ligt op een wal van heideplaggen om een kunstmatig hoogveentje met een vennetje.
    Will we loose the last active inland drift sands of Wester Europe? : the origin and development of inland drift-sand in The Netherlands.
    Riksen, M.J.P.M. ; Ketner-Oostra, H.G.M. ; Jungerius, P.D. ; Spaan, W.P. ; Goossens, D. ; Nijssen, M. ; Turnhout, C. van - \ 2006
    Landscape Ecology 21 (2006)3. - ISSN 0921-2973 - p. 431 - 447.
    campylopus-introflexus - dune area - moss - soils
    In the Netherlands the total active inland drift-sand area has been declining rapidly during the last 50 years. To preserve the inland drift sands, it is necessary to understand its origin and development and the role of human activity in this semi-natural ecotype. The objective of this literature review is to describe the development of the drift-sand ecotopes, to explain the rapid decline of the active drift sands, and to develop a management strategy for the remaining active drift sands. Inland drift-sand landscapes are relatively young landscapes of Holocene age. They often occur as oval-shaped cells with a length of 1.5 to over 6 km in the direction of the prevailing wind. These cells presumably represent reactivated deposits of Younger Cover Sands. Large-scale erosion events in combination with human activity suppressed the development of vegetation. After the change in land use in the first half of the 20th century in which most of the drift sands were re-afforested, the vegetation succession started to show a progressive development. In this stage inland drift-sand ecotopes developed in most of the remaining drift sands with all forms of the typical succession stages from bare sand to forest. The rate at which this development took place mainly depended on the geomorphological development stage of the area, the area size and human activity. Since the 1960s the increased nitrogen deposition has accelerated the vegetation succession, not only resulting in a further decline of the drift sands, but also in a loss of the fragile balance between the different ecotopes and loss of its typical habitants like the Tree Grayling and Tawny Pipit. Most drift-sand vegetation and fauna need the presence of bare sand nearby and a certain level of erosion activity to survive. To preserve the drift-sand ecotype, it is therefore recommended to keep the area affected by erosion sufficiently large (process management). In the meantime one should also `maintain' or increase the wind force in the drift-sand area by suppressing the growth of high vegetation and removing trees, which form a wind barrier. In areas which are less suitable for reactivation, one could restore the mosaic vegetation by removing the vegetation on a limited scale (pattern management). More research is needed to develop a more balanced management strategy and to develop a management tool for the managers of inland drift sands. Also the role of the increased nitrogen deposition in the regeneration process needs further investigation in order to find an effective way to suppress its effect. The development of management strategies for the Dutch inland drift sands might be of great value to drift-sand areas in Western Europe where nature conservationists start to show more interest in the restoration of former drift-sand areas.
    Lichen-rich coastal and inland sand dunes (Corynephorion) in the Netherlands: vegetation dynamics and nature management
    Ketner-Oostra, H.G.M. - \ 2006
    Wageningen University. Promotor(en): Karle Sykora. - [S.l.] : S.n. - ISBN 9789085045144 - 202
    corynephorus canescens - cladonia - duinen - duingraslanden - korstmossen - plantenecologie - vegetatiebeheer - natuurbescherming - hulpbronnenbeheer - nederland - natuurgebieden - corynephorus canescens - cladonia - dunes - dune grasslands - lichens - plant ecology - vegetation management - nature conservation - resource management - netherlands - natural areas
    Keywords: Acidification; Ammophila arenaria ; Campylopus introflexus ; Carex arenaria ; Cladonia ; Invasive species; Management; Nitrogen deposition; Species diversity; Spergulo-Corynephoretum; Succession; Violo-Corynephoretum; wildfire.

    The objective of this thesis was to describe long-term changes in the lichen-rich dry grassland communities in calcium-poor coastal dunes (on Terschelling) and inland dunes (of the Kootwijkerzand) in theNetherlands. Some of the changes that have occurred since the 1970s are due to natural succession. Others are caused by human-induced eutrophication and acidification through increased aerial inputs of nitrogen (mainly ammonia) since the 1970s. These effects of grass and moss encroachment on lichens were studied by comparing vegetation relevés from before the 1970s with the relevés made from 1990 onwards.

    In the calcium-poor coastal dunes,newsuccession stages have occurred in theViolo-Corynephoretum(V.-C.) where the short grass Corynephorus canescens has been replaced by tall graminoids like Ammophila arenara and Carex arenaria . In theSpergulo-Corynephoretum(S.-C.)of the non-calcareousdunesinland, it was foundthat Corynephoruscanescens was more vital, while Festuca ovina s.l. and Agrostis vinealis had increased. In addition, the moss Campylopus introflexus , an alien species from the southern hemisphere and adapted to acid open sand, invaded the dunes in both areas, outgrowing not only the rare lichens from the pioneer stages but also the more common pioneer species of decalcified sand. However, where this moss is less vital as a result of desiccation or being blown over by sand, common humicolous lichens and some pioneer species may act as secondary pioneers on these withered moss carpets.

    Another topic covered in this thesis is evaluation of small- and large-scale management measures aiming at restoring the former sand dune landscape with its high biodiversity. Small-scale management included cutting self-sown trees, and removing the canopy has positively influenced lichen-diversity in the inland dunes. The effect of a wildfire as possible management tool in both coastal and inland sand dune vegetation was not effectfull and grass- and moss-encraochment took over.

    Large-scale EGM restoration management (Effect-oriented measures against acidification and eutrophication) in both the nutrient-poor coastal and inland dunes in the early 1990s is evaluated using the data presented in this thesis and the recent end-evaluation of several long-term monitoring programmes.

    Recommendations for future restoration management to maintain or regain biodiversity in coastal and inland dunes are given. Additional measures to destroy the algal crust and the other vegetation by means of tillage techniques in a scheduled maintenance traject are recommended when large scale EGM restoration is applied. This seems necessary given that the current high N emission still exceeds the critical deposition values for the coastal V.-C.andthe inland S.-C. A further reduction of N emission from livestock farming should be pursued, so that the remaining biodiversity in the coastal and inland sand dune ecotope could be a source for more dispersion. This is essential not only for the lichen diversity, but also for all existing flora and fauna elements.

    Restoration of lichen diversity in grass-dominated vegetation of coastal dunes after wildfire
    Ketner-Oostra, H.G.M. ; Peijl, M.J. van der; Sykora, K.V. - \ 2006
    Journal of Vegetation Science 17 (2006)2. - ISSN 1100-9233 - p. 147 - 156.
    brittany heathlands - lime-poor - encroachment - netherlands - deposition - strategies - succession - soil
    Question: Can lichen diversity of an earlier succession stage be restored in dune grassland after fire in a region with high nitrogen deposition? Location: Calcium-poor coastal dunes in the Wadden district, The Netherlands. Methods: We sampled dune grassland by using a large continuous transect of 4 m x 4 m blocks on both a south slope and a west slope. The sampling was conducted in the lichen-rich Violo-Corynephoretum in 1966, in the vegetation dominated by tall graminoids in 1990 and in the recovering vegetation for eight years after a wildfire in 1993. Vegetation succession in the blocks is visualised in stacked bar graphs and ordination diagrams (DCA). In 1966 releves were made within the blocks, and from 1990 until 2001 permanent quadrats were studied. Results: Between 1966 and 1990 the lichen-rich open grassland became dominated by tall graminoids and developed partly into a dwarf-shrub heath, resulting in a severe loss of lichen diversity. After the fire a lush vegetation of tall graminoids with an abundant moss cover developed. In 2001 the vegetation was still very different from the lichen-rich vegetation in 1966. Conclusions: Fire alone will not change dunes dominated by tall graminoids into open lichen-rich grasslands in an area with high aerial nitrogen deposition. After fire, additional intervention is recommended, such as large-scale clearing of the burned vegetation and actively promoting deposition of sand, either blown in from foredunes, from re-activated blow-outs or artificially brought to the site.
    Lichenrijke stuifzanden in Noord-Limburg : verleden, heden en toekomst
    Ketner-Oostra, H.G.M. ; Douma, B.E. ; Ancker, H. van den; Jungerius, P.D. - \ 2005
    Natuurhistorisch Maandblad 94 (2005)6. - ISSN 0028-1107 - p. 109 - 116.
    geomorfologie - geologie - landschapsecologie - vegetatie - eolisch zand - korstmossen - plantengeografie - noord-limburg - geomorphology - geology - landscape ecology - vegetation - aeolian sands - lichens - phytogeography - noord-limburg
    Tijdens een vooronderzoek over mogelijk herstel van stuifzandvegetatie in de gemeente Bergen zijn vier natuurterreinen onderzocht waarvan de gegevens terug te vinden waren bij eerder onderzoek (Cleef en Kers, 1968). Een vergelijking is gemaakt met recent uitgevoerd onderzoek (Van den Acker, 2002). Het betreft een 90 ha groot verstuivingslandschap binnen Nationaal Park de Maasduinen
    De spagaat van de stuifzandbeheerder
    Borkent, I. ; Jungerius, P.D. ; Ketner-Oostra, H.G.M. - \ 2005
    Vakblad Natuur Bos Landschap 2 (2005)9. - ISSN 1572-7610 - p. 20 - 23.
    eolisch zand - landschapsecologie - vegetatiebeheer - landschapsbescherming - aeolian sands - landscape ecology - vegetation management - landscape conservation
    Het stuiven van zand blijkt een natuurlijk en autonoom ecologisch proces te zijn, dat niet persé het gevolg is van overmatig menselijk gebruik van hei en bos. Instandhouden van zandverstuivingen is volgens de auteurs het instandhouden van aardkundig en natuurlijk erfgoed. Veel meer dan het corrigeren van menselijke fouten
    De lichenenrijke stuifzandvegetatie met IJslands mos aan de voet van de Lemelerberg (Ov.) in de periode 1965-2005
    Ketner-Oostra, H.G.M. ; Tweel-Groot, L. van; Sparrius, L.B. - \ 2005
    Buxbaumiella 72 (2005). - ISSN 0166-5405 - p. 48 - 59.
    korstmossen - bodem-plant relaties - vegetatiebeheer - herstelbeheer - natuurreservaten - monitoring - salland - lichens - soil plant relationships - vegetation management - restoration management - nature reserves - monitoring - salland
    Aan de voet van de Lemelerberg ligt een zandverstuiving, een natuurreservaat dat beheerd wordt door Landschap Overijssel. In 2004 vond hier een vooronderzoek plaats om herstelmaatregelen te onderbouwen die tot doel hebben hier het stuifzandlandschap en de daarbij behorende biodiversiteit voor de toekomst veilig te stellen (Van den Ancker e.a., 2004). De lichenenrijkdom van dit gebied is al sedert 1965 bekend - met veel zeldzame en bedreigde licheensoorten waaronder een van de laatste vindplaatsen van IJslands mos (Cetraria islandica) in Nederland (Aptroot e.a., 1998). Thans ligt in dit terrein een meetpunt van het Landelijk Meetnet Korstmossen (Sparrius e.a., 2000). In genoemd vooronderzoek was literatuuronderzoek over de ontwikkeling van die lichenenrijkdom sedert 1965 een onderdeel van het vegetatie-onderzoek - en wordt hierbij gepresenteerd.
    Actief beheer voor het behoud van levend stuifzand. Eindrapport effect van beheersmaatregelen Kootwijkerzand. Deel 1: Vegetatie- en Winderosie-onderzoek
    Ketner-Oostra, H.G.M. ; Riksen, M.J.P.M. - \ 2005
    Wageningen : Wageningen University - 100
    Strategies and management measures for conservation and restoration of inland sand dunes (drift sands), with emphasis on the eastern part of The Netherlands
    Ketner-Oostra, H.G.M. ; Jungerius, P.D. - \ 2004
    In: Dünen und trockene Sandlandschaften. Gefährdung und Schutz. Tagungsband zu einer Veranstaltung am 6.10.2003 im Westfälischen Museum für Naturkunde in Münster Münster : Westfälicher Naturwissenschaftlicher Verein e.V. - ISBN 9783937455037 - p. 27 - 38.
    Veranderingen van de mos- en licheenvegetatie in de droge duinen van Terschelling sinds 1970
    Ketner-Oostra, H.G.M. - \ 2004
    Buxbaumiella 68 (2004). - ISSN 0166-5405 - p. 2 - 6.
    duingebieden - nederlandse waddeneilanden - mossen - korstmossen - inventarisaties - bodem-plant relaties - duneland - dutch wadden islands - mosses - lichens - inventories - soil plant relationships
    Hierbij volgen enkele aanvullingen over wat er de laatste decennia in de van oorsprong kalkarme duinen van Terschelling is veranderd. Dit in aanvulling op het artikel 'Mossen van Terschelling', dat verscheen in dit blad na een mossen-weekend eind 2000 en na een intensieve inventarisatie in de periode 2000-2001 (Van Tooren et al. 2002).
    Veranderingen in de korstmos-vegetatie van het Wekeromse Zand (II): een vergelijking tussen 1994 en 2004
    Ketner-Oostra, H.G.M. - \ 2004
    Buxbaumiella 67 (2004). - ISSN 0166-5405 - p. 49 - 56.
    korstmossen - achteruitgang (deterioration) - vegetatiekartering - bodem-plant relaties - eolisch zand - veluwe - lichens - deterioration - vegetation mapping - soil plant relationships - aeolian sands
    In the previous review (period 1984-1994) the subject of discussion was a decrease of the quantity of lichens in the nature reserve of 190 ha inland sand-dune landscape in the Veluwe region of Gelderland, while the species diversity remained high. In 1992- 1993 management measures in this reserve, such as the cutting and removing of 35 ha pine-trees and sod-cutting, were implemented in order to regain an open inland sand-dune landscape. In 2003 it became apparent that too much erosion had harmed the lichen-steppe in the northern part, which had changed into a pioneer vegetation with the moss Polytrichum piliferum. In the southern part with fewer dynamics, the influence was visible of the aerial nitrogen deposition. For the reserve as a whole the lichen diversity remained high, but since 1994 the quantity has decreased even more.
    Decline of lichen-diversity in calcium-poor coastal dune vegetation since the 1970s, related to grass and moss encroachment
    Ketner-Oostra, H.G.M. ; Sykora, K.V. - \ 2004
    Phytocoenologia 34 (2004)4. - ISSN 0340-269X - p. 521 - 549.
    atmospheric deposition - ammophila-arenaria - soil - netherlands
    Since the 1970s the encroachment by tall graminoids, especially of Ammophila arenaria, has changed the aspect of the calcium-poor 'grey dunes' of the Wadden Sea island Terschelling (The Netherlands) formerly dominated by Corynephorus canescens. In addition, the neophytic moss Campylopus introflexus, a species adapted to acid open sand invaded these dunes. In this paper the cryptogam vegetation inside dry dune-grassland (the Corynephorion, the Tortulo- and Polygalo-Koelerion) and dune-heath (Empetrion) before (the 1960s) and after these changes (the 1990s) are compared. It was found that in the former period the lichen diversity in several plant communities was very high, amounting to a total of 45 species, among which 10 epigeic growing species that are usually epiphytes. In the latter period, Campylopus introflexus not only outgrew the rare lichens from the pioneer stage of the Violo-Corynephoretum, but also the more common pioneer species of decalcified sand. However, when this moss has lower vitality through desiccation or being blown-over by sand, common humicolous lichens and some pioneer species may act as secondary pioneers on these withered moss carpets. In the 1990s some relatively open communities were still present in a transition stage of the Violo-Corynephoretum to the Phleo-Tortuletum and in the Phleo-Tortuletum itself, forming a suitable environment for some lichen pioneer species of subneutral sand, including some of the epigeic growing epiphytes.
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