Grazing on diatoms by harpacticoid copepods: species-specific density-dependent uptake and microbial gardening

Aquatic Microbial Ecology

Marleen De Troch¹  María Björk Steinarsdóttir Victor ChepurnovEmil Ólafsson¹ 

关键词: Copepoda;    Diatoms;    Grazing;    Assimilation;    Stable isotopes;   

DOI  :  10.3354/ame039135

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Four common intertidal harpacticoid species (Paramphiascella fulvofasciata, Tigriopus brevicornis, Nitocra spinipes and Harpacticus obscurus) were offered pelagic diatoms (Phaeodactylum tricornutum) as food inlaboratory experiments. To ensure generality we used copepod species originating from diverse habitats with different ecological characteristics. The diatoms were enriched in the stable carbon ¹³C isotope to facilitate tracing in theharpacticoids. Uptake of diatoms was clearly species-specific and in general P. fulvofasciata was more efficient than the other species. We found significant uptake by 24 h of incubation for T. brevicornis.From 24 h onwards we found anincrease for all 3 species. Species had similar δ¹³C values before and after starvation, indicating that labeled material was efficiently assimilated in their tissues. We tested whether diatom assimilation is density-dependent and thiswas true for 2 species (N. spinipes and P. fulvofasciata) but not for the semi-pelagic T. brevicornis. Finally, a positive effect of faecal pellets on food uptake for the less mobile species was shown, indicating that microbialgardening occurs within benthic harpacticoids as it does for several other crustacean species.

【 授权许可】

Unknown