Format

Send to

Choose Destination
See comment in PubMed Commons below
Sci Rep. 2011;1:30. doi: 10.1038/srep00030. Epub 2011 Jul 4.

Silicon uptake by sponges: a twist to understanding nutrient cycling on continental margins.

Author information

1
Centro de Estudios Avanzados de Blanes (CSIC), Acceso Cala St. Francesc 14, Blanes 17300, Girona, Spain. maldonado@ceab.csic.es

Abstract

About 75% of extant sponge species use dissolved silicon (DSi) to build a siliceous skeleton. We show that silicon (Si) uptake by sublittoral Axinella demosponges follows an enzymatic kinetics. Interestingly, maximum uptake efficiency occurs at experimental DSi concentrations two orders of magnitude higher than those in the sponge habitats, being unachievable in coastal waters of modern oceans. Such uptake performance appears to be rooted in a former condition suitable to operate at the seemingly high DSi values characterizing the pre-Tertiary (>65 mya) habitats where this sponge lineage diversified. Persistence of ancestral uptake systems causes sponges to be outcompeted by the more efficient uptake of diatoms at the low ambient DSi levels characterizing Recent oceans. Yet, we show that sublittoral sponges consume substantial coastal DSi (0.01-0.90 mmol Si m(-2) day(-1)) at the expenses of the primary-production circuit. Neglect of that consumption hampers accurate understanding of Si cycling on continental margins.

PMID:
22355549
PMCID:
PMC3216517
DOI:
10.1038/srep00030
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Nature Publishing Group Icon for PubMed Central
    Loading ...
    Support Center