Sample collection
Samples were collected in the Belgian part of the North Sea in autumn 2017 in four different habitats each characterized by a distinct macrobenthic community (Fig 1): 1/ a fine muddy habitat with low diversity and low abundances with mainly sessile burrowing dwelling species (Limecola balthica community, ZVL); 2/a coastal fine sand habitat, characterized by high diversity and high abundances with mainly sessile, tube building burrowers (Abra alba community, 120), 3/ a medium sandy habitat with low taxon richness and low abundances (Nephtys cirrosa community, 330) and 4/ an offshore coarse sandy habitat, with medium diversity and low abundances (Hesionura elongata community, 840). The latter two habitats are characterized by relatively small, free-living and burrowing macrobenthic species. In each of the four communities, three replicate Van Veen grabs (A,B and C) were collected on board of the RV Belgica. The sediment was sieved on board on a 1 mm sieve. All material (macrobenthos specimens + residue) that remained on the sieve was fixed in ethanol and stored at -20°C until further processing.