Macrobenthic diversity and sediment-water exchanges of oxygen and ammonium: Example of two subtidal communities of the eastern English Channel

作者：Rius Armonie Tous; Denis Lionel^*; Dauvin Jean Claude; Spilmont Nicolas

来源：Journal of Sea Research, 2018, 136: 15-27.

DOI：10.1016/j.seares.2018.02.007

• Benthic communities
• Sediment-water fluxes
• Organic carbon mineralization
• Eastern English Channel
• Macrofauna diversity
• Abra alba
• Ophiothrbc fragilis

In organic-rich shallow habitats, benthic macrofauna is known to play a major role in the geochemical functioning of surficial sediments through its metabolism, as well as its bioirrigation and/or bioturbation activity. In this paper, the effects of benthic macrofauna on metabolic fluxes at the sediment-water interface were studied at four dates, from winter to late summer, on two major macrobenthic communities of the eastern English Channel (macrotidal system): the fine sand Abra alba community (2 stations) and the sandy gravel Ophiothrix fragilis community (1 station). Oxygen and ammonium fluxes showed temporal changes that could be attributed to the variation of sea water temperature. Once the effect of temperature removed (using Q(10) = 2.5), the average fauna mediated fluxes (F-Fauna) represented respectively 77% and 76% of average total fluxes. Considering the whole dataset, species number and biomass showed a significant correlation with fauna mediated fluxes of O-2 and NH4+, while the relationships with abundance were not significant. The species composition of the community might influence ecosystem functioning, but in the present study, functional groups have a very poor relationship with F-Fauna (O-2) and F-Fauna (NH4+). Despite the presence of engineer species, establishing general and simple rules to link macrofaunal parameters to functional attributes remains very difficult, suggesting that communities rather followed the idiosyncrasy and rivet hypothesis.

• 出版日期2018-6