Vera Van Lancker

Royal Belgian Institute of Natural Sciences · Direction of Natural Environment

Modelling of surface and shallow subsurface data is getting more and more advanced and is demonstrated mostly for onshore (hydro)geological applications. Three-dimensional (3D) modelling techniques are used increasingly, and now include voxel modelling that often employs stochastic or probabilistic methods to assess model uncertainty. This paper pr...

A recently released voxel model quantifying aggregate resources of the Belgian part of the North Sea includes lithological properties of all Quaternary sediments and modelling-related uncertainty. As the underlying borehole data come from various sources and cover a long time span, data-related uncertainties should be accounted for as well. Applyin...

Based on data from Multibeam Echosounders (MBES) and Van Veen grab samples, near-field effects of marine aggregate extraction by trailing suction hopper dredgers in the Belgian part of the North Sea were assessed on a decadal scale. The combined approach allowed to investigate and compare seabed and macrobenthic community characteristics for three...

Subtidal natural hard substrates (SNHS) promote occupancy by rich benthic communities that provide irreplaceable and fundamental ecosystem functions, representing a global priority target for nature conservation and recognised in most European environmental legislation. However, scientifically validated methodologies for their quantitative spatial...

Tidal sand waves are rhythmic bedforms found on sandy continental shelves that pose a threat to offshore activities. While emphasis is placed on studying their natural morphodynamic evolution, little is known about if and how fast sand waves recover after dredging. This work presents an analysis of multibeam echosounder data collected at three form...

Chapter 1.1: Purpose and scope The purpose of this Document is to guide Member States in the review and update of the assessment of their marine waters in respect of each marine region or subregion, according to Article 17(2)(a) in conjunction with Articles 8(1) and 9(1) MSFD, which is due for reporting by 15 October 2024 and in subsequent reportin...

De Noordzee ligt vol zand, dat weten de meeste mensen wel. Elk jaar worden miljoenen kubieke meters van dit zand gewonnen om te gebruiken voor kustonderhoud en bouwprojecten. Wat veel minder mensen weten, is dat die uit zee gewonnen grondstof per locatie en ook met de diepte sterk verschilt. Je kunt dat al goed zien als je boorkernen of zelfs losse...

To protect the marine environment more effectively, the European Union adopted the Marine Strategy Framework Directive (MSFD) in 2008, aiming to achieve the Good Environmental Status (GES) of the EU's marine waters by 2020 and to protect the resource base upon which marine-related economic and social activities depend. A major challenge in the impl...

Bioturbation is one of the key mediators of biogeochemical processes in benthic habitats that can have a high contribution to seafloor functioning and benthic pelagic coupling in coastal waters. Previous studies on bio-turbation were limited to point locations and extrapolations in single regions, but have not accounted for regional differences und...

The expected increase of maritime activities in the North Sea and the growing awareness of its natural environmental value require enhanced science-based environmental advice for more efficient and effective marine management. The North Sea Open Science Conference organised by the Royal Belgian Institute of Natural Sciences and the Belgian Biodiver...

In the course of the last three decades fundamental marine geological research in Europe has grown to full maturity and has been thriving thanks to significant European financial support via collaborative research projects on a variety of topics, such as slope stability (e.g. COSTA, EUROMARGINS), gas hydrates (e.g. HYDRATECH, ANAXIMANDER), fluid fl...

The poor access to data on the marine environment is a handicap to government decision-making, a barrier to scientific understanding and an obstacle to economic growth. In this light, the European Commission initiated the European Marine Observation and Data Network (EMODnet) in 2009 to assemble and disseminate hitherto dispersed marine data. In th...

Three experiments were conducted in the Belgian part of the North Sea to investigate short-term variation in seafloor backscatter strength (BS) obtained with multibeam echosounders (MBES). Measurements were acquired on predominantly gravelly (offshore) and sandy and muddy (nearshore) areas. Kongsberg EM3002 and EM2040 dual MBES were used to carry o...

To characterize seafloor substrate type, seabed mapping and particularly multibeam echosounding are increasingly used. Yet, the utilisation of repetitive MBES-borne backscatter surveys to monitor the environmental status of the seafloor remains limited. Often methodological frameworks are missing, and should comprise of a suite of change detection...

Coastal sediments and continental shelves play a crucial role in global biogeochemistry, as they form the prime site of organic carbon burial. Bottom trawling and dredging are known to increasingly impact the coastal seafloor through relocation and homogenisation of sediments, yet little is known about the effects of such anthropogenic sediment rew...

Geographic decision support systems aim to integrate and process data originating from different sources and different data providers in order to create suitability models. A suitability model denotes how suitable geographic locations are for a specific purpose on which decision-makers need to make a decision. Particularly in the presence of volunt...

Bedforms as benthic habitats are studied increasingly as acquisition and analysis of acoustic data improve in capturing, visualizing and quantifying terrain variables on various scales. However, feedback mechanisms between geomorphology and benthos are not always clear and complexity increases where humans also affect the benthos-landscape relation...

With environmental scientists, social scientists, policy makers, marine managers and industries around the table, the North Sea Open Science Conference succeeded in collating a high level of cross-disciplinary expertise and cross-sectoral interests. All participants were indispensable for a unique science-policy-society trialogue in search for answ...

For sustainable management of marine geological resources, a geological knowledge base is being built for the Belgian and southern Netherlands part of the North Sea. Voxel models of the subsurface are used for predictions on sand and gravel quantities and qualities, to ensure long-term resource use. The voxels are filled with geological data from b...

A 1:250,000 scale map of the surface of the Top-Palaeogene for the Belgian Continental Shelf was created based on extensive analyses of older and recent geological and geophysical datasets. The Top-Palaeogene surface is an important polygenetic unconformity that truncates older strata of the Palaeogene and to a smaller extent some of Neogene age fr...

As human pressure on the marine environment increases, safeguarding healthy and productive seas increasingly necessitates integrated, time- and cost-effective environmental monitoring. Employment of a Wave Glider proved very useful for the study of sediment transport in a shallow sandbank area in the Belgian part of the North Sea. During 22 days, d...

Overview chapter on the geology and morphosedimentary dynamics of the Flemish coast and Belgian part of the North Sea

This chapter discusses the uncertainties associated with sediment data, which are a commonly neglected obstacle in collaborative seabed-habitat mapping, complicating harmonization. Standardization of these data, although an important prerequisite in the harmonization of surrogate-based habitat maps, is not enough to achieve full map uniformity. Thr...

Fine-scale seabed mapping (<5 m resolution) (e.g. surficial sediments, morphology and benthos) was conducted along the ebb-tidal delta of the Westerschelde estuary, Belgian and Dutch part of the North Sea. To understand variations in habitat and species distributions, mapping was combined with measurements of currents and turbidity throughout 13-hr...

There is international political momentum for the safeguarding and conservation of biodiversity (e.g. European Marine Strategy Framework Directive; Habitat Directive; Water Framework Directive). Mapping the distributions of all representative species is not possible therefore surrogates are frequently used in mapping efforts as measures of biologic...

For the survey of shellfish in the Dutch coastal zone (WOT Ensis), a fixed stratified sampling grid is used. Stratification is based on expectation of occurrence, for which previously observations by Spisula fishermen were used. Spisula subtruncata has largely disappeared and was replaced by Ensis sp. However, the stratified sampling grid is still...

Marine ecosystems on continental shelves endure an increasing burden of human activity offshore, and the impacts on benthic habitats are not well known. An improved understanding of how benthic habitats vary in relation to substrate types and seabed features is therefore essential to both scientists and offshore developers. This case study shows th...

Fine-scale geomorphological mapping is demonstrated to be able to predict macrobenthos occurrences within shallow sandbank areas of the Belgian part of the North Sea. The Belgian part of the North Sea (BPNS) is a siliciclastic macrotidal environment comprising several groups of sandbanks. The sandbanks represent a thin and patchy Holocene cover, wh...

Bertels, L.; Houthuys, R.; Deronde, B.; Janssens, R.; Verfaillie, E., and Van Lancker, V., 2012. Integration of optical and acoustic remote sensing data over the backshore foreshore nearshore continuum: a case study in Ostend (Belgium). Journal of Coastal Research, 28(6), 1426-1436. Coconut Creek (Florida), ISSN 0749-0208. This research addresses t...

Geomorphic terrain features relevant for habitat mapping have been reviewed and described in case studies from Denmark, Ireland and Belgium. The report proposes standardized scales and methods for mapping of ecologically relevant geomorphic features, and also recommends that future development of EUNIS should include formal integration of geomorpho...

To counter the degradation of marine ecosystems, a variety of legislative measurements are being developed, mainly under the umbrella of the Marine Strategy Framework Directive (MSFD). The policy behind this is to ensure that human activities are performed in a sustainable way, which means that the impact of all human activities on the marine syste...

This book started as an idea at the GeoHab meeting held in Noumea, New Caledonia, in May 2007. We noticed that multibeam bathymetry maps of geomorphic features, sometimes shown as 3D fly-thru movies, followed by detailed sampling and photographic data (including underwater videos) illustrating the substrate conditions and associated biota was a con...

Southeastern Bay of Biscay (Basque coast) seafloor characterization and benthic habitat mapping was carried out integrating data from multibeam echosounder, topographic and bathymetric LiDAR, video, and sediment and biological sampling ranging from the intertidal zone up to 100 m depth over 1,096 km 2. The area shows high geomorpho-logic diversity...

Concerns about human-induced degradation of marine ecosystems are presently being translated into European Directives aimed at a restoration of healthier seas. However, anthropogenic alterations are ancient and data on the pristine ecosystem are lacking, making the evaluation of their cumulative effects in the long run challenging. In the Belgian a...

The effect of hydro-meteorological forcings (tidal and wind-induced flows) on the transport of suspended particulate matter (SPM), on the formation of high-concentrated mud suspensions and on the occurrence of sand–mud suspensions has been studied using long-term multi-parametric observations. Data have been collected in a coastal turbidity maximum...

poster abstract

The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS...

poster abstract

Multi-sensor tripod measurements in the high-turbidity area of the Belgian nearshore zone (southern North Sea) allowed investigating storm effects on near bed suspended particulate matter (SPM) concentrations. The data have shown that during or after a storm the SPM concentration increases significantly and that high concentrated mud suspensions (H...

Introductory papers " European Marine Sand and Gravel Resources: Evaluation and Environmental Impacts of Extraction - an Introduction " European marine aggregates resources: Origins, usage, prospecting and dredging techniques " Marine Aggregate Extraction Regulation in EU Member States " Morphodynamic models used for studying the impacts ofoffshore...

A detailed geomorphological and sedimentological study has been performed at a tidal sandbank, which has been dredged during 30 years. Localised intensive aggregate extraction created a depression in the central part of the sandbank, upon which the Government decided to close this section of the bank for further exploitation. Multibeam and side-sca...

Analyses of the records of ships registers and Electronic Monitoring Systems, of the trailer suction hopper dredgers, operating on the Belgian Continental Shelf, reveal that since the beginning of extraction in 1976, 75% of the total extracted volume originates from only one sandbank, the Kwinte Bank. At present, two morphologically-distinguished d...

Sand extraction activities on the Belgian Continental Shelf are regulated, in the sense that no major changes to the seabed should occur and natural regeneration of the banks is considered to balance the extraction rates. However, the centre of a tidal sandbank (Kwinte Bank), exploited intensively since the 1970's, is transformed now into a depress...

Sandbanks are considered as primary targets for the marine aggregate industry, not only because of considerations related to resource quality and operational advantages, but also due to the notion that natural sediment transport processes that form and maintain sandbanks are able to counterbalance the loss of sediment due to extraction. This paper...

A basic requirement for allowing marine aggregate (sand) extraction on the Belgian Continental Shelf (which takes place on sandbanks) is that it should not result in major environmental changes. However, a tidal sandbank (Kwinte Bank, Flemish Banks), exploited intensively since the 1970’s, has shown evidence of significant morphological changes wit...

Long-term changes in the cohesive sediment distribution of the Belgian—Dutch nearshore zone (southern North Sea) are related to human activities (port construction, deepening of navigation channels, disposal of dredged sediments) and to natural variability, due to tides and meteorological effects. Results are based on the combined analyses of recen...

Mapping ecologically relevant zones in the marine environment has become increasingly important. Biological data are however often scarce and alternatives are being sought in optimal classifications of abiotic variables. The concept of ‘marine landscapes’ is based on a hierarchical classification of geological, hydrographic and other physical data....

In the nowadays highly pressurized marine environment, a science-based approach to management becomes increasingly important. In many cases, the sediment nature and processes are the key to the understanding of the marine ecosystem, and can explain particularly the presence of soft-substrata habitats. For predictions of the occurrence of species an...

The interaction of dumped sediments with the morphology and sedimentology of a coastal environment and the recovery of the seafloor after cessation of dumping activities, is still poorly known, especially from a longer term perspective. This paper presents a quantitative impact study of the dumping of dredged material on two overlapping disposal si...

Reefs of the tube-building polychaete Lanice conchilega are known to represent hotspots of biodiversity within inter- and subtidal soft sediments of the North Sea. However, because of their patchy distribution, point sampling does not appropriately map their subtidal spatial distribution. This study evaluated the feasibility to detect L. conchilega...

Airborne imaging spectroscopy data (AISA Eagle and HyMap) were applied to classify the sediments of a sandy beach in seven sand type classes. On the AISA-Eagle data, several classification strategies were tried out and compared with each other. The best classification results were obtained applying a linear discriminant classifier (LDC) in combinat...