Premium
Trophic positioning and microphytobenthic carbon uptake of biofilm‐dwelling meiofauna in a temperate river
Author(s) -
MAJDI NABIL,
TACKX MICHÈLE,
BUFFAN–DUBAU EVELYNE
Publication year - 2012
Publication title -
freshwater biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.297
H-Index - 156
eISSN - 1365-2427
pISSN - 0046-5070
DOI - 10.1111/j.1365-2427.2012.02784.x
Subject(s) - meiobenthos , trophic level , chironomidae , biology , ecology , food web , biofilm , larva , benthic zone , bacteria , genetics
Summary 1. δ 13 C and δ 15 N stable isotope signatures combined with an in situ microphytobenthic 13 C labelling experiment were performed on epilithic biofilms of a large temperate river (the Garonne, France) to infer the trophic positioning of biofilm‐dwelling meiofauna and their uptake of microphytobenthic carbon. 2. Chironomidae larvae and Chromadorina spp. nematodes rapidly incorporated freshly produced microphytobenthic carbon in contrast to Rhyacophilidae larvae and Naididae oligochaetes. Quantitatively, macrofaunal Chironomidae incorporated more microphytobenthic carbon per day than did meiofauna. Moreover, Chironomidae seemed more involved in the spatial export of microphytobenthic carbon than nematodes. 3. Rhyacophilidae larvae were predators feeding on large meiofauna (Naididae and Chironomidae) but not on nematodes. Naididae oligochaetes primarily gained their carbon from allochthonous and/or microbial‐loop recycled sources. 4. A rapid and significant loss of labelled microphytobenthic carbon was observed. Feeding activity of biofilm‐dwelling invertebrates seemed not to be primarily involved in this loss.