Kn. Mouritsen et al., Change of topography and sediment characteristics on an intertidal mud-flat following mass-mortality of the amphipod Corophium volutator, J MARINE BI, 78(4), 1998, pp. 1167-1180
Citations number
53
Categorie Soggetti
Aquatic Sciences
Journal title
JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM
A Corophium-bed characterized by a mosaic of emerged areas and tidal pools
during low water was established on an intertidal flat in the southern part
of the Danish Wadden Sea. In spring 1990, the plateaux harboured relativel
y high densities of the amphipod Corophium volutator, whereas the amphipods
were almost absent in the pools. Following a parasite-induced mass-mortali
ty in the population of Corophium, summer 1990, the plateaux of the bed wer
e subjected to sediment erosion, The heterogeneous plateau-pool structure d
isappeared, accompanied by increased median particle diameter and decreased
silt content in the former plateau sediment. These events were accompanied
by increased chlorophyll-a concentrations in the sediment of both plateau
and pool areas.
The results suggest Corophium volutator to be the single most important org
anism stabilizing the plateau sediment, and hence, the heterogeneous topogr
aphic structure of the Corophium-bed. It is proposed that the stabilizing e
ffect of Corophium burrows also in deeper sediment strata may outweigh the
surface stabilizing influence of epipelic diatoms, as well as the negative
effect of amphipods eating the diatoms, in non-cohesive coarser sediments.