Premium
Body size‐based trophic structure of a deep marine ecosystem
Author(s) -
RomeroRomero Sonia,
MolinaRamírez Axayacatl,
Höfer Juan,
Acuña José Luis
Publication year - 2016
Publication title -
ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.144
H-Index - 294
eISSN - 1939-9170
pISSN - 0012-9658
DOI - 10.1890/15-0234.1
Subject(s) - trophic level , pelagic zone , benthic zone , ecology , ecosystem , biology , zooplankton , invertebrate , marine ecosystem , allometry , oceanography , detritivore , geology
Nitrogen stable isotope ratios (δ 15 N) and body size were used to describe the size‐based trophic structure of a deep‐sea ecosystem, the Avilés submarine Canyon (Cantabrian Sea, Southern Bay of Biscay). We analyzed δ 15 N of specimens collected on a seasonal basis (March 2012, October 2012, and May 2013), from a variety of zones (benthic, pelagic), taxa (from zooplankton through invertebrates and fishes to giant squids and cetaceans), or depths (from surface to 4700 m) that spanned nine orders of magnitude in body mass. Our data reveal a strong linear dependence of trophic level on body size when data were considered either individually, aggregated into taxonomical categories, or binned into size classes. The three approaches render similar results that were not significantly different and yielded predator:prey body mass ratios ( PPMR ) of 1156:1, 3792:1 and 2718:1, respectively. Thus, our data represent unequivocal evidence of interspecific, size‐based trophic structure of a whole ecosystem based on taxonomic/functional categories. We studied the variability in δ 15 N not explained by body mass ( W ) using linear mixed modeling and found that the δ 15 N vs. log 10 W relationship holds for both pelagic and benthic systems, with benthic organisms isotopically enriched relative to pelagic organisms of the same size. However there is a marked seasonal variation potentially related to the recycling state of the system.