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Title: Towards high resolution habitat maps of the Southern North Sea
Author(s): E. Verfaillie (UGent), S. Degraer (UGent), D. Long (BGS), D. Maljers (TNO Building and Environment), K. Schelfaut (UGent), S. Van Heteren (TNO Building and Environment), W. Willems (UGent), V. Van Lancker (UGent)
Document owner: Els Verfaillie (els.verfaillie@ugent.be)
Reviewed by:
Workgroup:
MESH action: 4
Version: n/a
Date published:
File name: MESH_ElsVerfaillie_Dublin_150307_lowres.pdf
Language: English
Number of pages: 24 (including this page)
Summary: For this exercise, the methodology of Verfaillie et al. (2006) and Degraer et al. (in press) was applied to the Southern North Sea (UK, NL, B), resulting in sedimentological maps of the median grain size and the silt-clay percentage and four habitat suitability maps of macrobenthic communities.
Reference/citation: Powerpoint presentation: 14-15 March.2007 MESH Final Conference Dublin (IRL). “Towards high resolution habitat maps of the Southern North Sea” E. Verfaillie, S. Degraer, D. Long, D. Maljers, K. Schelfaut, S. Van Heteren, W. Willems, V. Van Lancker
Keywords: Sedimentological maps, macrobenthic communities, habitat suitability modelling, Southern North Sea
Bookmarks:
Related information:
TowardsTowards high high resolutionresolution habitat habitat mapsmaps of the Southern of the Southern NorthNorth SeaSea
Els VerfaillieEls Verfaillie11, Steven Degraer, Steven Degraer11, Dave Long, Dave Long22, Denise Maljers, Denise Maljers33, , KristienKristien SchelfautSchelfaut11, Wouter Willems, Wouter Willems11, Sytze Van Heteren, Sytze Van Heteren33, Vera , Vera
Van LanckerVan Lancker11
1 1 GhentGhent UniversityUniversity, , BelgiumBelgium2 British Geological Survey, United Kingdom2 British Geological Survey, United Kingdom
3 TNO Built Environment & Geosciences, Netherlands3 TNO Built Environment & Geosciences, Netherlands
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Aim of transnational initiative How do I make a (habitat) map?Habitat suitability maps on Belgian Continental ShelfSame exercise for Southern North SeaReflectionsValidation Concluding remarksReferences
ContentsContents
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Aim of transnational initiative (1)Aim of transnational initiative (1)Study area: Southern North Sea New maps of (median) grain size of sand fraction and silt clay percentage vs. existing Folk map: input for transnational modelling initiativesResolution 250 mTranslation of sedimentological maps into first habitat suitability maps of macrobenthiccommunities for S N Sea
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Aim of transnational initiative (2)Aim of transnational initiative (2)
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How do I make a (habitat) map? (1)How do I make a (habitat) map? (1)
STEP 1: Getting the best out of the ground truth data
STEP 2: Selecting and getting the best out of the coverage data
STEP 3: Integration of ground truth and coverage data
STEP 4: Habitat map design and layout
Focus on step 2, step 3 & step 4
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How do I make a (habitat) map? (2)How do I make a (habitat) map? (2)
STEP 1 STEP 2 STEP 3 STEP 4
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STEP 2: STEP 2: Selecting and getting the Selecting and getting the best out of the coverage data (1)best out of the coverage data (1)
Selection of relevant environmental variables: sediment type (median grain size, sorting, silt clay percentage), bathymetry and derivatives, energy (waves, currents),…For soft substrata grain size and silt claypercentage seem to be the most relevant, but other variables have to be examined (e.g. d10, d90, dx, bathymetric derivatives such as BPI)
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STEP 2 (2)STEP 2 (2)If point data -> full coverage map of relevant environmental variables by interpolationSome variables are full coverage already e.g. multibeam bathymetry or backscatter, side scan sonar, satellite imagery
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STEP 2 (3)STEP 2 (3)
R² (bathymetry – Ds50) for Belgian and Dutch Continental Shelf up to IJmuiden:
R2 = 0.3681
0
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0 5 10 15 20 25 30 35 40 45 50
Bathymetry (m)
D50
-san
d (m
icro
n)
Example of geostatistical interpolation of Ds50: Kriging with an external drift (KED) using bathymetry as secondary information
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460000 480000 500000 520000
5660
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0 5 102.5 kmUTM31N - WGS84 coordinates
Easting (m)
Nor
thin
g (m
)
−KED: median grain size (mu)
0 - 100100 - 200200 - 250250 - 300300 - 350350 - 400400 - 500500 - 600
STEP 2 (4)STEP 2 (4)KED vsOrdinaryKriging (OK): clear differencein depthdefined zones e.g. sandbanks-swales
Verfaillie et al. (2006)
OK
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STEP 2 (5)STEP 2 (5)Silt clay %
Ds50
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Macoma balthica Abra albacommunity
Nephtys cirrosa Ophelia limacinaMacoma balthicacommunity
Abra alba Nephtys cirrosacommunity
Ophelia limacinacommunity
Increasing silt-clay%
Increasing (median) grain-size
HABITAT model (Degraer et al., in prep.)• Quantification relation macrobenthos versus
silt-clay% and median grain-size• Multiple Discriminant Function Analysis• Community dependent accuracy
67 – 88 %, average 77 %
STEP 3: Integration of ground truth STEP 3: Integration of ground truth and coverage data (1)and coverage data (1)
macrobenthiccommunities(Van Hoey et al., 2004):
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Silt-clay%
Median grain-size
Application of HABITAT model
STEP 3 (2)STEP 3 (2)
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Habitat suitabilitymaps of 4 macrobenthiccommunities
STEP 4: Habitat map design STEP 4: Habitat map design and layoutand layout
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STEP 4: Habitat map design STEP 4: Habitat map design and layoutand layout
Translation of habitat suitabilitymaps intoEUNIS level 5 map
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Ds50
Silt-clay%Application of HABITAT model
SameSame exerciseexercise forfor Southern Southern NorthNorth SeaSea (1)(1)
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FIRST TRIAL VERSION!
SameSame exerciseexercise forfor Southern Southern NorthNorth SeaSea (2)(2)
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ReflectionsReflections on first trial of habitat suitability map of on first trial of habitat suitability map of macrobenthicmacrobenthic communities in soft substrata in the communities in soft substrata in the
Southern North Sea:Southern North Sea:Southern N Sea same biogeographical area with comparable sediment type and communitiesShading areas out of limits of model
Gravel?As gravel is not an input for the model, typical associated fauna will not be predicted!
High suitability of Abra alba community around shading areas are modelling artefacts
Trans-border modelling work not evident!Different resolution of input dataDifferent sampling methods and processing
Absence of Macoma balthica community around Western Scheldt estuary
Lower estimation of Dutch silt clay percentages?
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ValidationValidation of of coveragescoverages
OK KED: best results for allvalidationindices!
Verfaillie et al. (2006)
Until now: onlyvalidation forBelgiandataset!
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ValidationValidation of Habitat model of Habitat model
Three-fold cross validation of the empirical habitat suitability model using both median grain size and silt clay percentagea posteriori average CCI (i.e. correctly classified instances) of 77% (community-dependent CCI ranging from 67 to 88%) and a Cohen’s kappa of 0.67, pointing towards a high accuracy of the modelOnly done for Belgian dataset!
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Concluding remarksConcluding remarksFolk map (qualitative classes) vs Ds50 map and silt clay map (quantitative data): more useful as model inputExamination of other model inputs relevant for biological communities/species e.g. gravel, Dx, bathymetric derived mapsInteresting first results of habitat suitability maps of Southern North SeaCommunity vs species specific modelling (e.g. Willems et al., in press)Trans-border work remains difficult!
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ReferencesReferencesDegraer, S., E. Verfaillie, W. Willems, E. Adriaens, V. Van Lancker & M. Vincx (in prep.) Habitat suitability as a mapping tool for macrobenthic communities: An example from the Belgian part of the North Sea.Van Hoey, G., Degraer, S., Vincx, M., 2004. Macrobenthiccommunity structure of soft-bottom sediments at the Belgian Continental Shelf. Estuarine, Coastal and Shelf Science 59, 599–613.Verfaillie, E., Van Meirvenne, M. & Van Lancker, V., 2006. Multivariate geostatistics for the predictive modelling of the surficialsand distribution in shelf seas, Continental Shelf Research, 26 (19), 2454-2468.Willems, W., Goethals, P., Van den Eynde, D., Van Hoey, G., Van Lancker, V., Verfaillie, E., Vincx, M., Degraer, S. (in press). Where is the worm? Predictive modelling of the habitat preferences of the tube-building polychaete Lanice conchilega (Pallas, 1766). Ecological Modelling.
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NEW ENO INTERREG IIIB North West Europewww.nweurope.org
British Geological Survey (BGS)www.bgs.ac.uk
TNO – Netherlands Organisation for Applied Scientific Researchwww.tno.nl
Amgueddfa Cymru – National Museum of Waleswww.museumwales.ac.uk/en/biosyb/
IMARESwww.wageningenimares.wur.nl
Envision Mapping Ltdwww.envision.uk.com
Marine Institutewww.marine.ie
Natural Englandwww.naturalengland.org.uk
Ifremerwww.ifremer.fr/rebent
Agri-Food and Biosciences Institutewww.afbini.gov.uk
Ghent Universitywww.ugent.be
Centre for Environment, Fisheries and Aquaculture Science (CEFAS)www.cefas.co.uk
Joint Nature Conservation Committee (JNCC)www.jncc.gov.uk
WAGEN IN GEN IMARESWAGEN IN GEN IMARES
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