Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    '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.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Current refinement(s):

Records 1 - 20 / 246

  • help
  • print

    Print search results

  • export

    Export search results

  • alert
    We will mail you new results for this query: keywords==coastal areas
Check title to add to marked list
Postmortaal onderzoek van bruinvissen (Phocoena phocoena) uit Nederlandse wateren, 2016
IJsseldijk, L.L. ; Kik, M.J.L. ; Solé, L. ; Gröne, A. - \ 2017
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 96) - 41
phocoena - postmortale onderzoeken - kustgebieden - phocoenidae - nederland - postmortem examinations - coastal areas - netherlands
This annual report presents the results of post-mortem examinations of porpoises stranded on the Dutchcoast. One of the main objectives of the research is to quantify human-induced causes of death. In 2016, 55dead harbour porpoises were examined: 31 males and 24 females, including 14 adults, 33 juveniles and 8neonates. Most of the harbour porpoises examined died as a result of grey seal attacks (31%), infectiousdiseases (29%) or food shortage (18%). Bycatch was the cause of death in 11% of the harbour porpoisesexamined
Ecologisch gericht suppleren : verslag pilot multi-method survey 2016
Couperus, Bram ; Baptist, Martin ; Burggraaf, Dirk ; Dijkman-Dulkes, André ; Perdon, Jack ; Post, Marjolijn ; Verdaat, Hans - \ 2017
Wageningen : Wageningen Marine Research (Wageningen Marine Research rapport C007/17) - 32
kustgebieden - bemonsteren - protocollen - mariene ecologie - coastal areas - sampling - protocols - marine ecology
Waardekaarten van: Haisborough, Hammond & Winterton, North Norfolk Sandbanks & Saturn Reef
Hintzen, N.T. - \ 2017
IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C009/17) - 18 p.
vissen - visserij - waarden - kaarten - natura 2000 - groot-brittannië - kustgebieden - fishes - fisheries - values - maps - great britain - coastal areas
Langs de Engelse kust staan een aantal gebieden op de UK Natura 2000 agenda voor sluiting voor de Nederlandse demersale vloot. Wageningen Marine Research bestudeerde in hoeverre de Nederlandse vloot actief was in dit gebied en hoe de voorgenomen te sluiten gebieden overlappen met voor de visserij interessante visgronden. Een grotere opbrengst (factor 3) wordt gehaald uit het North Norfolk Sandbanks & Saturn Reef gebied (dit is één gebied) ten opzichte van het Haisborough, Hammond and Winterton gebied (dit is ook één gebied). Vooral tong word in dit eerste gebied gevangen terwijl scholvangsten groter zijn in het tweede gebied. De voornaamste visgronden die interessant zijn voor de Nederlandse sector zijn niet opgenomen in de voorgenomen te sluiten gebieden, waarbij juist voor de visserij interessante delen van de totale zoekgebieden niet aangemerkt zijn als te sluiten gebied.
Fresh Water Lens Persistence and Root Zone Salinization Hazard Under Temperate Climate
Stofberg, Sija F. ; Oude Essink, G.H.P. ; Pauw, Pieter S. ; Louw, Perry G.B. de; Leijnse, Anton ; Zee, Sjoerd E.A.T.M. van der - \ 2017
Water Resources Management 31 (2017)2. - ISSN 0920-4741 - p. 689 - 702.
Fresh water lens - Root zone salinization - Salinity - Simple model - salinization - fresh water - models - water supply - coastal areas - zoutgehalte - verzilting - zoet water - modellen - watervoorziening - kustgebieden

In low lying deltaic areas in temperate climates, groundwater can be brackish to saline at shallow depth, even with a yearly rainfall excess. For primary production in horticulture, agriculture, and terrestrial nature areas, the fresh water availability may be restricted to so-called fresh water lenses: relatively thin pockets of fresh groundwater floating on top of saline groundwater. The persistence of such fresh water lenses, as well as the quantity and quality of surface water is expected to be under pressure due to climate change, as summer droughts may intensify in North-West Europe. Better understanding through modelling of these fresh water resources may help anticipate the impact of salinity on primary production. We use a simple model to determine in which circumstances fresh water lenses may disappear during summer droughts, as that could give rise to enhanced root zone salinity. With a more involved combination of expert judgement and numerical simulations, it is possible to give an appraisal of the hazard that fresh water lenses disappear for the Dutch coastal regions. For such situations, we derive an analytical tool for anticipating the resulting salinization of the root zone, which agrees well with numerical simulations. The provided tools give a basis to quantify which lenses are in hazard of disappearing periodically, as well as an impression in which coastal areas this hazard is largest. Accordingly, these results and the followed procedure may assist water management decisions and prioritization strategies leading to a secure/robust fresh water supply on a national to regional scale.

TBT-gehalten en effecten bij de Gewone Alikruik, de Gevlochten Fuikhoorn en de Purperslak langs de Nederlandse kust in 2016
Kotterman, M. ; Jol, J. ; Barneveld, E. van - \ 2016
IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C110/16) - 35
gastropoda - organo-tinverbindingen - bemonsteren - kustgebieden - toxicologie - nederland - organotin compounds - sampling - coastal areas - toxicology - netherlands
River export of nutrients to the coastal waters of China: the MARINA model to assess sources, effects and solutions
Strokal, Maryna - \ 2016
University. Promotor(en): Carolien Kroeze, co-promotor(en): S. Luan; Lin Ma. - Wageningen : Wageningen University - ISBN 9789462579729 - 226
cum laude - nutrients - rivers - coastal water - models - eutrophication - coastal areas - water pollution - china - voedingsstoffen - rivieren - kustwateren - modellen - eutrofiëring - kustgebieden - waterverontreiniging

Rivers export increasing amounts of nitrogen (N) and phosphorus (P) to the coastal waters of China. This causes eutrophication problems that can damage living organisms when oxygen levels drop and threaten human health through toxic algae. We know that these problems result from human activities on land such as agriculture and urbanization. However, the relative importance of these human activities for river export of nutrients to Chinese seas is not well studied. There are two important issues that need further investigation: the relative importance of upstream pollution on downstream impacts and the relative importance of typical sources of nutrients in Chinese rivers that are often ignored in existing modeling studies.

My PhD thesis, therefore, aims to better understand trends in river export of nutrients to the coastal waters of China by source from sub-basins, and the associated coastal eutrophication. To this end, I developed the MARINA model: Model to Assess River Inputs of Nutrients to seAs. For this, I used the existing Global NEWS-2 model (Nutrient Export from WaterSheds) as a starting point.

I formulated five sub-objectives to achieve the main objective:

To analyze the original Global NEWS-2 model for river export of nutrients and the associated coastal eutrophication (Chapter 2);

To develop a sub-basin scale modeling approach to account for impacts of upstream human activities on downstream water pollution, taking the Pearl River as an example (Chapter 3);

To quantify the relative share of manure point sources to nutrient inputs to rivers at the sub-basin scale (Chapter 4);

To quantify the relative share of sources to river export of nutrients at the sub-basin scale (Chapter 5);

To explore optimistic futures to reduce river export of nutrients and coastal eutrophication in China (Chapter 6).

The study area includes rivers draining roughly 40% of China. This includes the most densely populated areas, and areas with intensive economic activities. The rivers include the Yangtze (Changjiang), Yellow (Huanghe), Pearl, Huai, Hai and Liao. In the MARINA model, the drainage areas of the large Yangtze, Yellow and Pearl rivers are divided into up-, middle- and downstream sub-basins. The principle of the sub-basin approach of MARINA is that nutrients from human activities are transported by tributaries to outlets of sub-basins and then to the river mouth (coastal waters) through the main channel. The model takes into account nutrients that are partly lost or retained during transport towards the river mouth. The model quantifies river export of nutrients by source from sub-basins for 1970, 2000 and 2050.

The main six findings of the MARINA results for China are:

Finding 1: Dissolved N and P export by Chinese rivers increased by a factor of 2-8 between 1970 and 2000;

Finding 2: The potential for coastal eutrophication was low in 1970 and high in 2000 in China;

Finding 3: Most dissolved N and P in Chinese seas is from middlestream and downstream human activities;

Finding 4: Manure point sources are responsible for 20-80% of dissolved N and P in Chinese rivers;

Finding 5: In the future, river export of nutrients may increase in the Global Orchestration (GO) scenario of the Millennium Ecosystem Assessment. Current policy plans (CP scenario) may not sufficient to avoid this increase;

Finding 6: In optimistic scenarios (OPT-1 and OPT-2), the potential for coastal eutrophication is low in 2050, mainly as a result of assumed full implementation of: (1) high recycling rates of animal manure (OPT-1 and OPT-2), and (2) high efficiencies of nutrient removal in sewage systems (OPT-2, see Figure 1).

Figure 1. Illustration of future scenarios for coastal water quality in China. GO is Global Orchestration of the Millennium Ecosystem Assessment and assumes environmental actions that are either absent or ineffective in reducing water pollution. CP is based on GO, but incorporates the “Zero Growth in Synthetic Fertilizers after 2020” policy. OPT-1 and OP-2 are optimistic scenarios that assume high nutrient use efficiencies in agriculture (OPT-1, OPT-2) and sewage (OPT-2).

My PhD thesis reveals novel insights for effective environmental policies in China. It shows the importance of manure point sources in water pollution by nutrients. Clearly, managing this source will likely reduce coastal eutrophication in the future. Furthermore, the implementation of advanced technologies is essential when dealing with urban pollution. My PhD thesis may also be useful for other world regions with similar environmental problems as in China. The new, sub-basin scale MARINA model is rather transparent and thus can be applied to other large, data-poor basins that may benefit from the allocation of effective management options. With this I hope to contribute to future availability of sufficiently clean water for next generations, not only in China, but also in other world regions.

Broedsucces van kustbroedvogels in de Waddenzee in 2014
Koffijberg, K. ; Cremer, J.S.M. ; Boer, P. de; Postma, J. ; Oosterbeek, K. - \ 2016
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 78) - 40
wadvogels - broedvogels - vogels - kustgebieden - monitoring - waddenzee - wadden sea birds - breeding birds - birds - coastal areas - wadden sea
Data have been collected on the breeding success of several characteristic coastal breeding birds in theWadden Sea each year since 2005. Ten birds species considered representative of specific habitats and foodgroups are being monitored. The coastal breeding birds reproduction monitoring network is run as an ‘earlywarning system’ to follow the reproductive capacity of the bird populations in the Wadden Sea andunderstand the processes underlying fluctuations in populations. It is a valuable addition to the monitoring ofpopulation numbers and is carried out under a trilateral agreement with Germany and Denmark (TMAP). Theresults from 2014 show that many species of coastal breeding birds are still facing difficulties. The breedingsuccess of Eurasian Oystercatcher, Pied Avocet, Black-headed Gull, Common Tern and Arctic Tern inparticular is too low or much too low to maintain a stable population. In contrast, the breeding success ofHerring Gull is better than a few seasons ago. Erection of electric fencing around breeding sites of PiedAvocet and Black-headed Gull to protect them from predation has led to higher nest success. The maincauses of poor breeding performance appear to be predation by foxes and brown rats and insufficient foodavailability for the young
WOT schelpdiermonitoring in de Nederlandse kustzone in 2016
Perdon, K.J. ; Troost, K. ; Asch, M. van; Jol, J. - \ 2016
Den Helder : Wageningen Marine Research (Wageningen Marine Research report C093/16) - 34
shellfish - shellfish fisheries - coastal areas - netherlands - schaaldieren - schaal- en schelpdierenvisserij - kustgebieden - nederland
De visserij op schelpdieren in de Nederlandse kustwateren heeft zich ontwikkeld van een vrije visserij tot een sterk gereguleerde visserij waarbij naast economische ook ecologische doelstellingen nagestreefd worden. In het kader van de uitvoering van dit beleid is een bestandsopname van Amerikaanse zwaardscheden (Ensis directus), halfgeknotte strandschelpen (Spisula subtruncata), en de overige veel voorkomende soorten met een potentieel belang voor visserij, uitgevoerd door Wageningen Marine Research (IMARES). Het onderzoek is uitgevoerd in opdracht van het Ministerie van Economische Zaken: programma Wettelijke Onderzoekstaken, BAS code: WOT-05-001-018-IMARES-3. De inventarisatie is uitgevoerd in het voorjaar van 2016 en is daarmee de 22ste opeenvolgende gebiedsdekkende survey die op deze manier sinds 1995 wordt uitgevoerd.
Friese en Groninger Kwelderwerken : monitoring en beheer 1960-2014
Duin, W.E. van; Jongerius, H. ; Nicolai, A. ; Jongsma, J.J. ; Hendriks, A. ; Sonneveld, C. - \ 2016
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 68) - 95
zoutmoerassen - monitoring - vegetatie - ecologische successie - natuurbescherming - natuurbeheer - groningen - friesland - kweldergronden - kustgebieden - salt marshes - vegetation - ecological succession - nature conservation - nature management - salt marsh soils - coastal areas
Een belangrijk ecologisch doel voor de Waddenzee is een zo groot en natuurlijk mogelijk areaal kwelders. Mede daarom wordt in de half-natuurlijke kwelderwerken langs Friese en Groninger vastelandskust het beheer geleidelijk aangepast naar duurzamer en minder kunstmatig. Langetermijnmonitoring door
Rijkswaterstaat van hoogte- en vegetatieontwikkeling begeleidt deze verandering. Het gemiddelde areaal kwelder en pionierzone voldoet ruimschoots aan de voor de kwelderwerken gestelde eisen. Echter door opslibbing worden kwelders hoger, waarbij de vegetatie door successie verandert en er uiteindelijk een soortenarme vegetatie van Zeekweek kan ontstaan. Een bijkomend effect in de kwelderwerken is dat er door successie, op termijn, weinig ruimte overblijft in de overgangszone van laaggelegen wad naar hooggelegen horizontaal uitbreidende kwelder voor pioniervegetatie met Zeekraal, terwijl de Waddenzee daar het belangrijkste gebied voor is. Beweiding vertraagt weliswaar de ontwikkeling naar climaxvegetatie, maar voor grotere algehele natuurlijkheid zou meer dynamiek, waarbij aangroei en afslag van kwelders in evenwicht zijn door cyclische successie, uitkomst kunnen bieden. Er gaat onderzocht worden of een aangepast beheer van de rijshoutdammen hierbij kan helpen.

Haalbaarheid mosselteelt binnen offshorewindparken in de Nederlandse kustzone
Kamermans, P. ; Soma, K. ; Burg, S.W.K. van den - \ 2016
Den Helder : IMARES Wageningen UR (IMARES rapport C075/16) - 47 p.
mussel culture - mussels - coastal areas - offshore - wind farms - netherlands - mosselteelt - mossels - kustgebieden - windmolenpark - nederland
De grootschalige ontwikkeling van offshorewindparken roept de vraag op in hoeverre medegebruik van de ruimtes mogelijk is. Bij het ministerie van Economische zaken leeft de vraag of mosselteelt binnen de recentelijk aangewezen offshorewindparken haalbaar is.
Annual brown shrimp (Crangon crangon) biomass production in Northwestern Europe contrasted to annual landings
Tulp, I.Y.M. ; Chen, C. ; Haslob, Holger ; Schulte, Katharina ; Siegel, V. ; Steenbergen, J. ; Temming, A. ; Hufnagl, M. - \ 2016
ICES Journal of Marine Science 73 (2016)10. - ISSN 1054-3139 - p. 2539 - 2551.
coastal areas - Crustaceans - Mortality - shrimp fisheries - swept-area estimate - Wadden Sea
The brown shrimp (Crangon crangon) fishery is economically one of the most important fisheries in the North Sea. Fishing is unregulated, apart from the number of licenses and technical measures. The fishery has long been considered sustainable in terms of the effect on the target species, even though annual stocks are not regularly assessed. Average landings constantly increased annually and since 2000 have been 40% higher than in the 1980s and 1990s. Because brown shrimp lack a clear age structure and reproduce almost year-round, an agebased stock assessment is not possible. In the absence of a formal estimate of stock size, it is difficult to judge whether current fishing practices
can still be considered sustainable. Here, we use annual survey data collected during peak occurrence in late summer to obtain a depth- and area-stratified, swept-area estimate for the period 1970–2015. The resulting estimate of the total commercial-size shrimp biomass varied between 4000 and 21 000 tonnes over the years. Both parametric and non-parametric methods arrived at very similar results. In combination with length-based mortality estimates (as a proxy for production/biomass ratio), knowledge on the seasonal occurrence,
catchability, gear efficiency, and their variation, total adult annual biomass production was estimated. Values ranged between 38 000 and 216 000 tonnes and overlapped at the lower end with total annual commercial landings, which varied between 8000 and 38 500 tonnes, indicating that in some years (1977, 1998, 2007), the larger part of the total brown shrimp production was harvested. Annual brown shrimp landings have gradually increased since the series started, whereas no trend in standing biomass and production was detected. Concurrent with the increase in landings, natural mortality of shrimp by predation has diminished. Considering the increase in fishing pressure and unknown consequence if natural predators recover or shrimp recruitment decreases, the lack of management for the brown shrimp fishery needs to be reconsidered.
Building with Nature pilot Zandmotor Friese IJsselmeerkust : hoe effectief is de zandmotor als ecodynamische strategie voor het versterken van de Friese IJsselmeerkust
Wiersma, A.P. ; Hattum, T. van; Lange, H.J. de; Slobbe, E.J.J. van - \ 2016
Wageningen : Alterra, Wageningen-UR (Alterra-rapport 2706) - ISBN 9789462578357 - 150 p.
coastal management - coastal areas - sand - lake ijssel - netherlands - sand suppletion - kustbeheer - kustgebieden - zand - ijsselmeer - nederland - zandsuppletie
Dit rapport beschrijft de resultaten van de monitoring van de Building with Nature pilot langs de Friese IJsselmeerkust in de periode 2011 t/m 2015. De monitoring van de experimenten met zandmotors bij Workum en Oudemirdum is gericht op het begrijpen van het gedrag van de zandmotor, de effecten op de kust en op de ecologie. De monitoring loopt door tot en met 2017, dit rapport is dan ook te beschouwen als een tussenstand. Omdat er in 2016 een MIRT-pre-verkenning start met als doel het vaststellen van compenserende maatregelen langs de Friese IJsselmeerkust voor het veranderende peilregime van het IJsselmeer is het opportuun om nu met deze tussenstand van monitoringsresultaten te komen. In 2017 worden de definitieve resultaten gepubliceerd.
Monitoring en Evaluatie Pilot Zandmotor Fase 2 : Datarapport benthos bemonstering vooroever en strand najaar 2015
Wijsman, J.W.M. - \ 2016
IMARES (Rapport / IMARES C006/16) - 71 p.
sediment - benthos - bemonsteren - kustgebieden - terrestrische ecologie - nederland - sampling - coastal areas - terrestrial ecology - netherlands
Van 24 augustus tot en met 16 oktober 2015 is er een bemonstering uitgevoerd van het benthos en de sedimentkarakteristieken bij de Zandmotor. De vooroever is bemonsterd met de Van Veen happer (120 stations) en de bodemschaaf (109 stations). Het strand is bemonsterd tijdens de ebfase met een meetframe (70 stations). In deze rapportage worden de resultaten van het sediment en de schaafbemonstering gepresenteerd en vergeleken met voorgaande jaren.
The ecological effects of deep sand extraction on the Dutch continental shelf : Implications for future sand extraction
Jong, M.F. de - \ 2016
University. Promotor(en): Han Lindeboom; P. Hoekstra, co-promotor(en): Martin Baptist. - Wageningen : Wageningen University - ISBN 9789462576834 - 164 p.
sand - coastal areas - ecology - marine environment - marine ecology - aquatic ecosystems - netherlands - zand - kustgebieden - ecologie - marien milieu - mariene ecologie - aquatische ecosystemen - nederland
Eco-engineered coastal defense integrated with sustainable aquatic food production in Bangladesh (ECOBAS)
Tangelder, M. ; Ysebaert, T. ; Chowdhury, Shah ; Reinhard, A.J. ; Doorn, F. ; Hossain, M. ; Smaal, A.C. - \ 2015
IMARES (Report / IMARES C048/15) - 39 p.
coastal areas - coastal management - food production - bangladesh - kustgebieden - kustbeheer - voedselproductie
The objective of the ECOBAS project is to provide the coastal people of Bangladesh with an alternative approach for adaptation to coastal erosion and flooding. By using the concept of “eco-engineering” the natural resistance of shellfish reefs against hydrodynamic forces reduces human vulnerability to coastal erosion and flooding, and delivers a source of aquatic food. ECOBAS stands for ECO-engineered Coastal Defence Integrated with Sustainable Aquatic Food Production in BAngladeSh, and was executed by a multidisciplinary team of Dutch and Bangladesh research institutes. This report summarizes the outcomes of this study. It is not an in-depth report where scientific outcomes are discussed, but a summary for the funding agencies. The ECOBAS project was funded by Partners for Water. Also the Embassy of the Kingdom of the Netherlands financed extra monitoring activities in the second phase of the project which enabled generation of more data and a broader understanding of the research.
Hoogovenslakken in de natuur: wat nu?
Dorssers, Ben ; Wamelink, G.W.W. ; Groenenberg, J.E. - \ 2015
Vakblad Natuur Bos Landschap 12 (2015)120. - ISSN 1572-7610 - p. 16 - 19.
kustgebieden - zandsuppletie - vegetatie - vegetatiemonitoring - sintels - coastal areas - sand suppletion - vegetation - vegetation monitoring - slags
In Zuid-Holland is de kust de afgelopen jaren op verschillende plaatsen verstevigd door zandsuppletie. Niet alleen omwille van een betere kustbescherming maar ook voor natuurontwikkeling en recreatie. In sommige gebieden ligt de opgespoten zeebodem echter bezaaid met slakken afkomstig van de metaalproductie. Tot nog toe was het niet duidelijk of deze slakken negatieve effecten hebben op het milieu en of deze slakken invloed hebben op de vegetatieontwikkeling. Doel van het onderzoek is het bepalen van het effect van metaalslakken op de ontwikkeling van de vegetatie en de uitloging van zware metalen naar de bodem en het grondwater in het gebied Spanjaards Duin. Er is niet onderzocht wat het effect van de metaalslakken op de fauna is.
Dynamiek van schelpdierbanken in de nederlandse kustzone
Kamermans, P. ; Goudswaard, P.C. ; Asch, M. van; Bos, O.G. - \ 2015
Yerseke : IMARES (Rapport / IMARES C186/15) - 31 p.
schaaldieren - dynamica - aquatische ecosystemen - kustgebieden - kustwateren - karteringen - nederland - shellfish - dynamics - aquatic ecosystems - coastal areas - coastal water - surveys - netherlands
VIBEG Monitoring T1 in 2015 - Data Deelrapportage
Goudswaard, P.C. ; Bakker, A.G. ; Asch, M. van; Smith, S.R. ; Weide, B.E. van der; Brummelhuis, E.B.M. ; Cuperus, J. - \ 2015
Yerseke : IMARES (Rapport / IMARES C172/15) - 24 p.
natuurbescherming - zeevisserij - zonering - beschermde gebieden - kustgebieden - bemonsteren - noordzee - nederland - nature conservation - marine fisheries - zoning - reserved areas - coastal areas - sampling - north sea - netherlands
Het ‘VIBEG (Visserij in Beschermde Gebieden) akkoord’ betreft twee Habitat- en Vogelrichtlijngebieden: ‘Noordzeekustzone’ en ‘Vlakte van de Raan’. Het doel van dit akkoord is om de instandhoudingsdoelen te realiseren voor habitattype H1110B en schelpdieretende vogels in het kader van Natura2000, in combinatie met een ecologisch verantwoorde en duurzame visserij in deze gebieden. Om dit doel te bereiken is voor de Noordzeekustzone in december 2011 een zonering ingesteld met verschillende toegangsregels voor de visserij. Om de mogelijke effecten van deze verschillende visserijregimes op het bodemleven te kunnen vaststellen is in 2013 een onderzoeksprogramma opgestart voor benthische organismen en vissen. Met drie verschillende en elkaar aanvullende technieken: boxcorer, bodemschaaf en garnalennet, is in 2013 een eerste bestandsopname (T0) gemaakt op twee locaties in de Noordzeekustzone: Petten en Ameland. In 2015 is een tweede bestandsopname (T1) gemaakt, wederom op de twee locaties in de Noordzeekustzone: Petten en Ameland. In dit rapport worden de resultaten van de bestandsopname in 2015 gepresenteerd. Een vergelijking tussen de data van 2015 en 2013, zoals die gerapporteerd zijn in Goudswaard et al. (2014), zal in een later stadium plaatsvinden.
De kustnatuur is slecht beschermd : Het ruimtelijke ordeningsrecht gaat toch in verregaande mate uit van het piepsysteem
Kistenkas, F.H. ; Nijhuis, L. ; Schönknecht-Vermeulen, Carla - \ 2015
Vakblad Natuur Bos Landschap 12 (2015)119. - ISSN 1572-7610 - p. 6 - 6.
kustgebieden - kustbeheer - natuurbescherming - ruimtelijke ordening - landschapsbeheer - coastal areas - coastal management - nature conservation - physical planning - landscape management
Natuurlijk is de natuur in onze kustgebieden goed beschermd. Want we beschermen daar niet alleen natuur, maar ook het hele achterland. Dat moet goed zijn geregeld. Toch? Maar weten we er het fijne wel van? Wat zijn eigenlijk de garanties voor de bescherming? Niet iedereen is er van overtuigd dat de kustnatuur goed is beschermd.
Modelling foredune dynamics in response to climate change
Keijsers, J.G.S. - \ 2015
University. Promotor(en): Coen Ritsema, co-promotor(en): Michel Riksen; Alma de Groot. - Wageningen : Wageningen University - ISBN 9789462575844 - 186
klimaatverandering - duinen - kustgebieden - vegetatie - sedimentatie - hoogwaterbeheersing - modelleren - nederland - climatic change - dunes - coastal areas - vegetation - sedimentation - flood control - modeling - netherlands

Coastal dunes are prominent features along many of the world’s sandy shorelines. They are valued for their contributions to flood protection, biodiversity, fresh water supply and recreation. The most seaward dune ridge or foredune is the most dynamic part, showing fluctuations in size and morphology in response to erosion by the sea and subsequent recovery by interactions between wind-blown sand and vegetation. Given their dependency on multiple natural processes, coastal dunes may be particularly sensitive to the effects of climate change, including sea-level rise (SLR) and changes in temperature and precipitation.

To mitigate anticipated coastal erosion in the next decades, the Dutch sand nourishment regime will be intensified to raise the beach profile proportionally to the SLR. However, it is not clear how the added sand is distributed within the foredune system and whether this enables foredunes to keep up with sea-level rise. In addition, possibilities for dune re-mobilisation are investigated to enhance landward transport and biodiversity. However, effects of this intervention on foredune dynamics and the dune landscape are not entirely clear.

This thesis has examined yearly to decadal scale foredune dynamics and the impacts of climate change and management options on these dynamics.

Which factors control year-to-year variations in dune growth on the Dutch coast?

Dunes depend on aeolian transport for sand supply. While measurements of aeolian transport show complex spatio-temporal variations, we find that the yearly sand supply to dunes along the Dutch coast is relatively constant, between 10-20 m3/m irrespective of the beach width (Chapter 2). This means that a wider beach does not necessarily provide more sand to dunes and beach width is not a limiting factor in sand supply to the dunes.

In contrast to the sand input, the amount of sand lost during a storm surge does depend on the beach width. Wider beaches are able to dissipate more of the incoming wave energy and thus protect the dune better than narrow beaches. On a term of decades, this gives rise to steady dune growth on wider beaches and irregular, frequently interrupted growth on narrow ones.

How do biogeomorphic interactions control foredune shape?

The distribution of sand over the foredune, and therefore the morphological evolution, is strongly tied to vegetation patterns (Chapter 3). It was found that deposition patterns across foredunes show a characteristic distribution, starting with a sharp increase upon crossing the seaward vegetation limit, reaching a maximum between 5-20 m further landward and then gradually decreasing inland of the crest. The deposition pattern is further modified by the general vegetation pattern. On a timescale of years, there is no correlation between density of vegetation cover and the amount of accretion. However, by accounting for the gradual depletion of the sand load over the foredune, an empirical relationship can be defined between vegetation cover and its sand trapping efficiency. For fully covered surfaces, sand trapping efficiency is around 50%, indicating that sediment can pass densely covered foredunes.

Although literature suggests a relation between the level of plant burial and plant growth, we found no evidence for enhanced vegetation growth in high-deposition zones. A gain in vegetation cover was found to occur for burial between 0 m/year and 1 m/year, which indicates that lower and upper tolerance limits of burial have not been exceeded. Other growth limiting factors are likely to be of similar importance, masking any possible dependency of vegetation growth on sand accretion.

What are the effects of climate change on meso-scale evolution of coastal dunes?

The results on yearly erosion/accretion and sedimentation patterns were implemented in a computer for dune evolution called DUBEVEG, developed in Wageningen (Chapter 4). Algorithms for aeolian transport and vegetation growth were taken from existing models and combined with a new module for wave action and dune erosion. The model was calibrated and validated against field measurements. The good agreement between observations and predictions indicates that the model successfully incorporates the suite of biogeomorphic and marine processes involved in dune building.

Model simulations show that the evolution of a dune strongly depends on the sequence of storms and quiet periods. During quiet periods, dunes are able to build seaward at several metres per year as vegetation colonises the area near the dune foot, leading to dune accretion. Following the dune-foot position through time, we find an irregular pattern of seaward advance and regression. However, the average of a large number of runs with varying storm sequences reveals a clear trend. For a given wave climate and beach profile, we find that the model predicts a certain seaward limit to which the foredunes may build, or equilibrium position at which erosion and accretion are balanced. If the momentary position of the dune foot is seaward of this limit, seaward movement can be rapid. If, in contrast, the momentary position is at or seaward of the limit, periods of minor seaward growth are followed by periods of landward retreat, resulting in an oscillation around the equilibrium.

Climate scenarios, consisting of SLR and a gradual change in vegetation growth, were developed to examine climate-change effects on dune dynamics. Sea-level rise largely determines the direction of dune evolution by forcing the dune-foot landwards. The rate of rising controls whether dunes are able to preserve their height or sand volume while migrating landwards. The effect of changing vegetation growth rates, resulting from climate change, is most manifest in dune response to large disturbances. If vegetation is removed halfway into the simulation, vegetation growth rate determines whether a foredune will re-vegetate and re-stabilise: a value below the threshold will preclude complete recovery and the dune remains bare.

What management options are available to mitigate climate-change effects on coastal dune evolution?

Sand nourishments are effective to mitigate the effect of SLR on coastal dunes. Model results show that by raising the beach proportionally to SLR, dunes are able to preserve their dunefoot position, height and volume. sHowever, the associated landward retreat is often not feasible.

A reduction in vegetation cover, related to either (1) artificial remobilisation, (2) dunefoot erosion or (3) climate change promotes landwards transport and therefore contributes to the long-term preservation of a wider dune zone. If vegetation growth is reduced as a consequence of increasing summer drought, re-mobilisation becomes more effective, with high rates of landwards transport persisting for several decades.

On the long term, it is recommended to use a combination of sand nourishments and remobilisation efforts to preserve the coastline, promote landwards transport and make benefit of a dune’s natural self-regenerating capacity. Under the precondition that safety requirements are met, these natural processes enable long-term preservation of flood protection, biodiversity and dynamic landscapes.

Check title to add to marked list
<< previous | next >>

Show 20 50 100 records per page

 
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.