Sebastiaan Martinus Arens

• PhD
• Research Director at Bureau for Beach and Dune Research

This English translation of the Foredune Dynamisation Manual (original Dutch title Handleiding dynamiseren zeereep), arising from the Program for a Rich Wadden Sea, has been produced with the aim of making the Dutch experience of re-mobilisation interventions to create more dynamic sand dune landscapes available to a wider English-speaking audience...

Coastal dunes worldwide are increasingly under pressure from the adverse effects of human activities. Therefore, more and more restoration measures are being taken to create conditions that help disturbed coastal dune ecosystems regenerate or recover naturally. However, many projects lack the (open-access) monitoring observations needed to signal w...

Coastal dunes worldwide are increasingly under pressure from the adverse effects of human activities. Therefore, more and more restoration measures are being taken to create conditions that help disturbed coastal dune ecosystems regenerate or recover naturally. However, many projects lack (open-access) monitoring observations needed to signal wheth...

https://www.youtube.com/watch?v=RjdVpParY20 making Notches in coastal dunes

Blowouts can mitigate the negative effects of acidification in the topsoil, especially in industrialized countries with high atmospheric nitrogen (N) deposition. However, blowout activity may differ between lime‐rich and lime‐poor dunes, which creates different regional responses and interactions between processes and patterns. To further explore t...

The Dutch coastal landscape is of great international importance due to the large continuous surface of beach, dunes, salt marshes and mudflats. The combination of abiotic factors forms the basis for a large-scale varied landscape that, due to the presence of many environmental gradients, wet-dry, salt-fresh, acid-alkaline, sandy-silty, open-closed...

An open‐source quantitative model for predicting coastal foredune growth at monthly to multi‐annual (meso)temporal scales is developed. The model builds on the established fetch framework as a surrogate for the complex micro‐scale aeolian processes on the beach, to which rain and groundwater‐induced spatiotemporal surface moisture dynamics are adde...

In industrialized countries, biodiversity is threatened by high atmospheric N deposition. In coastal dunes, blowouts can mitigate this through deposition of fresh sand, but lime-rich and lime-poor dunes may differ in blowout activity. We studied natural blowout activity and explanatory factors in 2000 and 2014 in up to 51 sites along the Dutch coas...

The way in which sediment is transported (creep, saltation, suspension), is traditionally interpreted from grain size distribution characteristics. However, the grain size range associated with transitions from one transport mode to the other is highly variable because it depends on the amount of transport energy available. In this study we present...

In their recently published paper, Delgado-Fernandez et al. (2019) critically review the limitations and dangers of the relatively recent shift towards dune rejuvenation management in North-western Europe. We would like to comment on the paper from the Dutch perspective.

In the Netherlands it is common to nourish the coastline with sand from the seabed. Foredunes are replenished with sand from the beach and can be transported further into the dune area. We investigated whether nourishment material alters the phosphorus (P) content of dune soil and the nitrogen (N):P ratio of dune vegetation in two areas: a mega san...

Abstract. The way in which sediment is transported (creep, saltation, suspension), is traditionally interpreted from grain size distribution characteristics. However, the grain size range associated with transitions from one transport mode to the other is highly variable because it depends on the amount of transport energy available. In this study...

http://qsr.waddensea-worldheritage.org/reports/beaches-and-dunes

Variability in aeolian sediment transport rates have traditionally been explain by variability in wind speed. Although it is recognised in literature that limitations in sediment supply can influence sediment transport significantly, most models that predict aeolian sediment transport attribute a dominant role to the magnitude of the wind speed. In...

Coastal dune management in The Netherlands and New Zealand seeks to restore dune mobility by removing vegetation. Different methods are used to remove vegetation – mechanical excavation in the Netherlands and chemical means in New Zealand. This paper compares a herbicide-based restoration project at Doughboy Bay, New Zealand to mechanical-based pro...

In this paper a new model approach for describing aeolian sediment transport in supply limited situations is presented. It is aimed to formulate a model which can handle both supply limited as transport limited conditions. The model consists of a 1D linear advection model where Bagnold type 3rd power sediment transport formulations are used to calc...

Het gebied Oerderduinen betreft een oud, gestabiliseerd duincomplex dat ten westen en ten oosten geflankeerd wordt door de kwelders van het Nieuwlandsrijd en De Hôn. Het beheer van het gebied bestaat tot dusverre grotendeels uit “niets doen”. Dat wil zeggen dat de werking van wind en water heel lang via de natuurlijke processen verstuiving, opslibb...

This paper discusses and compares results of management interventions to remobilise dunes and obtain more autonomous changes in foredunes resulting from a change in coastal defence policy. In recent decades, nature conservation managers tried to restore aeolian dynamics and dune mobility landward of foredunes to maintain threatened, rare pioneer sp...

Op verzoek van OBN deskundigenteam Duin- en Kustlandschap, Provincie Zeeland, en de twee grote duinbeheerders Staatsbosbeheer en Natuurmonumenten op Schouwen is een verkenning uitgevoerd naar de herstelmogelijkheden van duindynamiek in de Meeuwenduinen en de Zeepeduinen (beide onder de noemer Westduinen Schouwen in dit rapport). De herstelmaatregel...

Ecological response of foredunes to nourishments. Changes in habitat types and vegetation. Gradients of sand transport over foredunes. Response of fauna.

a number of examples of restoration projects with dune mobility along the mainland coast of the Netherlands

In the past couple of years, new coastal-dune research has sprung up in the Netherlands. In this paper, we give an overview of ongoing projects at Wageningen UR, Deltares, TU Delft and UTwente: how these are connected and what type of questions are addressed. There is an increasing demand for the understanding and prediction of coastal dune dynamic...

This paper presents a new modelling concept for aeolian transport on beaches. Many research is invested in describing aeolian sediment transport for desert situations. Some of the principles of aeolian sediment transport in deserts are valid for application at the coastal zone but, where in deserts abundant sand is available for transport, in coast...

Summary Dune mobility; is sand supply through the foredunes the key to success? Bas Arens, Luc Geelen, Harrie van der Hagen & Rienk Slings coastal dunes, mobility, aeolian dynamics, restoration In this paper we discuss mechanisms for dune mobility and stability, with special reference to the Dutch situation. Currently in the Netherlands, as in othe...

In the past couple of years, new coastal-dune research has sprung up in the Netherlands. In this paper, we give an overview of ongoing projects at Wageningen UR, Deltares, TU Delft and UTwente: how these are connected and what type of questions are addressed. There is an increasing demand for the understanding and prediction of coastal dune dynamic...

In this paper we discuss mechanisms for dune mobility and stability, with special reference to the Dutch situation. Currently in the Netherlands, as in other parts of western Europe, dunes are in a phase of stabilization, which results in loss of biodiversity. Dune grasslands, rich in Red List species disappear gradually because of shrub encroachme...

Dit Uitvoeringsprogramma Monitoring en Evaluatie pilot Zandmotor beschrijft de evaluatiesystematiek en het monitoringplan voor de pilot Zandmotor voor de periode 2011 tot en met 2021. Het is in opdracht van Rijkswaterstaat Waterdienst gezamenlijk opgesteld door Deltares en IMARES met medewerking van Vertegaal ecologisch advies en onderzoek en Arens...

Waar kan je sneller een landschap zien veranderen dan aan de kust? Sommige veranderingen vallen direct op, bijvoor-beeld na een flinke storm. Andere veranderingen gaan geleidelijker. Voorbeeld hiervan zijn de kerven in de zeereep van de Noordsvaarder op Terschelling, misschien wel het begin van nieuwe paraboolduinen. Bas arens Rokende stuifkuilen D...

Zandsuppleties werken. De miljoenen bakken zand die voor de kust in zee gestort worden hebben effect. De erosie van de kustlijn is gestopt. Het zand vindt ook zijn weg naar de duinen. Hoewel nog veel onduidelijk is over de effecten van suppleties op de natuur, licht recent onderzoek een tipje van de sluier: de zeereep is de afgelopen dertig jaar st...

Inventory of sediment budgets in response to nourishments for the Duch coast as a whole and a number of study areas in particular. Response of foredunes to nourishments, response types

Kustverdedigen door middel van suppleties, het regel-matig storten van zand uit de zeebodem op strand of vooroever, blijkt te werken. We zijn in staat om de kust op zijn plaats te houden: wat erodeert vullen we weer aan met zand. De nieuwe trend is zelfs 'vooruit' te denken: door veel suppleren de kust uit te laten breiden. Maar wat zijn de effecte...

Kustverdedigen door middel van suppleties, het regel-matig storten van zand uit de zeebodem op strand of vooroever, blijkt te werken. We zijn in staat om de kust op zijn plaats te houden: wat erodeert vullen we weer aan met zand. De nieuwe trend is zelfs 'vooruit' te denken: door veel suppleren de kust uit te laten breiden. Maar wat zijn de effecte...

Beheerders op de Friese Waddeneilanden heb-ben al de nodige ervaring met dynamisch kustbeheer. Wat zijn hun bevindingen? Wat heeft het opgeleverd voor de natuur? Hoe kijken de eilanders tegen deze veranderingen aan? Kustveiligheid en dynamisch zeereepbeheer Voor de veiligheid van onze kustverdediging zijn twee begrippen van belang: de basiskustlijn...

Zeerepen met een volledig natuurlijke oorsprong zijn er nauwelijks. Dat maakt de zeereep bij Groote Keeten extra bij-zonder. Het is dus een stukje kust waar we zui-nig op moeten zijn. Vreemd genoeg is het gebied bij bijna niemand bekend. Daarom realiseert men zich de bijzondere waarden onvoldoende en zijn er bedreigingen. Doodsteek In verband met d...

Op sommige plekken langs de Westerschelde is er een begin van duinvorming, bij-voorbeeld in de vorm van ingestoven zand in een vloedmerk. Meer ontwikkelde duinen vin-den we er maar op een paar plaatsen: de Kaloot nabij de kerncentrale van Borssele, en de Hooge Plaaten ten noorden van Breskens. De duinen bij Breskens en verder westwaarts vor-men een...

Near Schoorl in The Netherlands a gap was created in the foredunes during a nature development project in 1997. This resulted in considerable aeolian sand transport and allowed the sea to enter the swale valley behind the foredunes during storm events. From 1997 to 2002 a monitoring program was carried out and various data sets were collected. This...

Interview met Frans Beekman over zijn proefschrift

In this paper we discuss mechanisms for dune mobility and stability, with special reference to the Netherlands. Currently in the Netherlands, as in other parts of western Europe, dunes are in a phase of stabilization, which results in loss of biodiversity. Provides durable dune mobility a solution to maintain biodiversity? Is durable dune mobility...

ARENS, S.M. and GEELEN, L.H.W.T., 2006. Dune landscape rejuvenation by intended destabilisation in the Am-sterdam water supply dunes. Journal of Coastal Research, 22(5), 1094–1107. West Palm Beach (Florida), ISSN 0749-0208. In the Dutch coastal dunes, several projects have started in which aeolian activity is stimulated to enhance landscape rejuven...

Er zijn inmiddels talloze voorbeelden van nieu-we natuur (zie artikel over website nieuwe na-tuur in dit nummer). Soms is daarbij een oude situatie hersteld, maar vaak ook een nieuwe si-tuatie gecreëerd. Er zijn goede voorbeelden, en er zijn totale mislukkingen. En er zijn voorbeel-den waarvan velen vinden dat de natuur ge-slaagd is, maar waar je j...

Pioneer stages in Dutch coastal dunes are under thread. In several areas experiments are executed to reactivate dunes. The aim is to restore aeolian processes in order to create new possibilities for the development of pioneer vegetation. How successful are these experiments? This paper compares the results of three different projects from three di...

Experiment Sinds een aantal jaren experimenteert PWN Water-leidingbedrijf Noord-Holland in de Kennemerduinen met het remobiliseren van paraboolduinen. Deze proe-ven moeten uitwijzen of duinmobiliteit in het huidige klimaat en met de huidige stikstofbelasting mogelijk is. Het uiteindelijke doel is om via een eenmalige ingreep een duurzaam proces op...

Pioneer stages in Dutch coastal dunes are under threat. In several areas experiments are executed to reactivate dunes. The aim is to restore aeolian processes in order to create new possibilities for the development of pioneer vegetation. How successful are these experiments? This paper compares the results of three different projects from three di...

A parabolic dune in the Netherlands was remobilised in December 1998 by removing vegetation and soil. The main aim of the experiment was ecological: to investigate whether permanent rejuvenation at the landscape scale is possible by restoration of natural processes. If processes can be reactivated at coarse scale, periodic rejuvenation of the lands...

Fast-response wind and turbulence instruments, including sonic anemometers, are used more and more in aeolian sediment transport research. These instruments give information on mean wind, but also on fluctuations and turbulent statistics, such as the uw covariance, which is a direct measure of Reynolds' stress (RS) and friction velocity. This paper...

In recognition of the environmentally sensitive nature of inlets and of a requirement to improve present knowledge of their function, the INDIA project has studied a small natural tidal inlet located in the Ría Formosa, Algarve, Portugal. The project has used state-of-the-art field equipment to study present day processes, and a range of numerical...

RESUMO Dunas costeiras formam um sistema único e importante, que pode ser móvel ou fixo. A vegetação de dunas é reconhecida como sendo escassa e não aumentar com aumento de precipitação e temperatura, como ocorre com plantas em outros solos. As razões desse fato residem no grande espaço entre os poros nas areias das dunas e na baixa percentagem de...

Suspended sand is sampled at several heights and positions on a beach and foredune, providing detailed insight into the vertical and horizontal variation in sand content in the air during landward transport. Grain-size analysis is used to study the changes in grain-size distribution during landward transport. Mean grain size and sorting decrease du...

Fast response wind and turbulence instruments, including sonic anemometers are used more and more in the research of aeolian sediment transport. These instruments provide data on mean wind, but also on friction velocity, wind speed fluctuations and turbulence statistics, such as the U-W and W-T covariance (CUW and CWT), which are a measure for the...

Vegetation density on foredunes exerts an important control on aeolian sediment transport and deposition, and therefore on profile development. In a long-term monitoring field experiment, three plots were planted with regular grids of reed bundles in three different densities: 4, 2 and 1 bundles per m2. This study reports on the differences in prof...

This paper discusses a model which simulates dune development resulting from aeolian saltation transport. The model was developed for application to coastal foredunes, but is also applicable to sandy deserts with transverse dunes. Sediment transport is calculated using published deterministic and empirical relationships, describing the influence of...

This paper discusses a model which simulates dune development resulting from aeolian saltation transport. The model was developed for application to coastal foredunes, but is also applicable to sandy deserts with transverse dunes. Sediment transport is calculated using published deterministic and empirical relationships, describing the influence of...

This paper discusses a two-dimensional second-order closure model simulating air flow and turbulence across transverse dunes. Input parameters are upwind wind speed, topography of the dune ridge and surface roughness distribution over the ridge. The most important output is the distribution of the friction velocity over the surface. This model is d...

The rationale and methods of construction of foredunes in The Netherlands and New Jersey, USA are identified and used to explain their genesis, locations, mobility, internal and external characteristics and temporal scales of evolution. Dunes are then ranked according to the degree they are modified by human processes. The lower level of protection...

Describes the multi-disciplinary, international EU MAST III Project INDIA and summarises the project's objectives, work plans and results to date. The fundamental aim of the INDIA project is to obtain an improved understanding of interactive processes in and adjacent to a small tidal inlet. The project started on 1 November 1997 and involves numeri...

I do not know how this got here and I don't see how to delete it. The actual article is: J. H. VAN BOXEL, S. M. ARENS AND P. M. VAN DIJK (1997) AEOLIAN PROCESSES ACROSS TRANSVERSE DUNES. I: MODELLING THE AIR FLOW. Earth Surf. Process. Landforms 24, 255-270 (1999). ABSTRACT This paper discusses a two-dimensional second-order closure model simulati...

Doel van het project "Fysische modellering zeereepontwikkeling" is de ontwikkeling van een model waarmee effecten van beheersmaatregelen op de morfologische ontwikkeling van de zeereep kunnen worden voorspeld, teneinde daarmee het zeereepbeheer te optimaliseren. Dit model bestaat uit een tweetal deelmodellen. Een stromingsmodel berekent de luchtstr...

This paper describes the appearance and maintenance of crescentic dunes in high wind speed conditions on a frozen beach at Schiermonnikoog, The Netherlands. The dunes were cresentic forms with horns. They were barchanoidal in plan view, but had reverse morphologies to typical barchans: the highest and steepest slopes were upwind and led to long low...

I do not know how this got here and I don't see how to delete it. The actual article is: P. M. VAN DIJK, S. M. ARENS AND J. H. VAN BOXEL (1999) AEOLIAN PROCESSES ACROSS TRANSVERSE DUNES. II: MODELLING THE SEDIMENT TRANSPORT AND PROFILE DEVELOPMENT. Earth Surf. Process. Landforms 24, 319-333 (1999). ABSTRACT This paper discusses a model which simu...

Sediment dynamics on a coastal foredune on the Dutch Wadden island of Schiermonnikoog were studied from November 1990 to May 1991 to get an insight into rates and frequencies of aeolian processes. Digital Terrain Models were constructed to describe volume changes and zonation of deposition. Recording of heights were related to important events. Thr...

The aeolian development of coastal foredunes is studied at two sites along the Dutch coast. Amounts of sand transport are measured in cross-sections over the foredunes, and changes in surface height are monitored. Sand transport decreases rapidly landward of the vegetation boundary. Near the dunefoot, changes in surface roughness and topography gen...

Short term field measurements of aeolian transport, using a saltiphone, indicate that actual rates of transport deviate considerably from the potential rates predicted by transport equations. When examined in detail, however, potential rates are approached during special conditions: mostly when the wind blows offshore, parallel or slightly oblique...