Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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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
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.
Impacts on biomass, nutrients and water
Schmidt, P. ; Poels, R.L.H. ; Ketner, P. ; Jonkers, W.B.J. - \ 2011
In: Sustainable Management of Tropical Rainforests / Werger, M.J.A., Paramaribo : Tropenbos International (Tropenbos Series 25) - ISBN 9789051131017 - p. 100 - 135.
Impacts on forest structure and plant diversity
Schmidt, P. ; Jonkers, W.B.J. ; Ketner, P. ; Dijn, B.P.E. De - \ 2011
In: Sustainable Management of Tropical Rainforests / Werger, M.J.A., Paramaribo : Tropenbos International (Tropenbos Series 25) - ISBN 9789051131017 - p. 74 - 99.
Prospects for the CELOS Management System (Part III: Conclusions and recommendations)
Jonkers, W.B.J. ; Graaf, N.R. de; Hendrison, J. ; Ketner, P. ; Mohren, G.M.J. ; Schmidt, P. ; Hout, P. van der; Kanten, R.F. ; Zagt, R.J. - \ 2011
In: Sustainable Management of Tropical Rainforests - The CELOS Management System / Werger, M.J.A., Paramaribo : Tropenbos International, Paramaribo, Suriname (Tropenbos Series 25) - ISBN 9789051131017 - p. 257 - 263.
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 - vegetation - plant succession - netherlands - restoration management
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).
Kleine knotszegge (Carex hartmanii Caj.) op Terschelling zevenendertig jaar gevolgd: een syntaxonomische en synecologische analyse
Ronde, I. de; Sykora, K.V. - \ 2009
Stratiotes 2009 (2009)38. - ISSN 0928-2297 - p. 32 - 43.
vegetatie - ecologie - cyperaceae - taxonomie - nederlandse waddeneilanden - vegetation - ecology - taxonomy - dutch wadden islands
De Kleine knotszegge is in ons land alleen bekend van het Mierenplak op Terschelling. Hier werd de eerste vondst gedaan door M. Jacobs (1950), maar niet als zodanig herkend. In 1966 werd de zegge opnieuw waargenomen (P. Ketner) en naar het Rijksherbarium gezonden. In 1977 maakte Ketner opnieuw vegetatieopnamen van deze plek. Om te onderzoeken of achteruitgang heeft doorgezet is in 2003 een vegetatieonderzoek in het Mierenpark verricht. Daarover wordt in dit artikel verslag gedaan
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.
Differences in regeneration between hurricane damaged and clear-cut mangrove stands 25 years after clearing
Ferwerda, J.G. ; Ketner, P. ; McGuiness, K.A. - \ 2007
Hydrobiologia 591 (2007)1. - ISSN 0018-8158 - p. 35 - 45.
marina forsk vierh - avicennia-marina - rhizophora-apiculata - natural regeneration - seedling growth - predation - forest - salinity - establishment - propagules
The effect of human disturbance on mangrove forest may be substantially different from the effects of natural disturbances. This paper describes differences in vegetation composition and structure of five vegetation types in two mangrove areas near Darwin, Australia, 25 years after disturbance. The vegetation in clear-felled forest showed more adult Avicennia marina than in the hurricane-affected forest, and a virtual absence of A. marina juveniles and saplings. This indicates that A. marina will be replaced by other species in the canopy, showing a multi-phase vegetation development in mangrove forest after human disturbance. The mechanism of disturbance and the conditions after clearing therefore affects the vegetation composition for at least 25 years after this disturbance took place.
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 - 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 9085045142 - 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
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
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
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.
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