Please use this identifier to cite or link to this item:
Title: Functional differences in the allometry of the water, carbon and nitrogen content of gelatinous organisms
Author: Molina-Ramírez, Axayacatl
Cáceres, Carlos
Romero-Romero, Sonia
Bueno, Juan
Ignacio González-Gordillo, J.
Irigoien, Xabier
Sostres, Jorge
Bode, Antonio
Mompeán, Carmen
Puelles, Mariluz Fernández
Echevarria, Fidel
Duarte, Carlos M.
Luis Acuña, José
Keywords: gelatinous organisms
carbon content
water content
body weight
Issue Date: 2015
Publisher: Oxford
Abstract: We have supplemented available, concurrent measurements of fresh weight (W, g) and body carbon (C, g) (46 individuals, 14 species) and nitrogen (N, g) (11 individuals, 9 species) of marine gelatinous animals with data obtained during the global ocean MALASPINA 2010 Expedition (totalling 267 individuals and 33 species for the W versus C data; totalling 232 individuals and 31 species for the N versus C data). We then used those data to test the allometric properties of the W versus C and N versus C relationships. Overall, gelatinous organisms contain 1.13 ± 1.57% of C (by weight, mean ± SD) in their bodies and show a C:N of 4.56 ± 2.46, respectively, although estimations can be improved by using separate conversion coefficients for the carnivores and the filter feeders. Reduced major axis regression indicates that W increases isometrically with C in the carnivores (cnidarians and ctenophores), implying that their water content can be described by a single conversion coefficient of 173.78 gW(g C)−1, or a C content of 1.17 ± 1.90% by weight, although there is much variability due to the existence of carbon-dense species. In contrast, W increases more rapidly than C in the filter feeders (salps and doliolids), according to a power relationship W = 446.68C1.54. This exponent is not significantly different from 1.2, which is consistent with the idea that the watery bodies of gelatinous animals represent an evolutionary response towards increasing food capture surfaces, i.e. a bottom-up rather than a top-down mechanism. Thus, the available evidence negates a bottom-up mechanism in the carnivores, but supports it in the filter feeders. Last, N increases isometrically with C in both carnivores and filter feeders with C:N ratios of 3.89 ± 1.34 and 4.38 ± 1.21, respectively. These values are similar to those of compact, non-gelatinous organisms and reflect a predominantly herbivorous diet in the filter feeders, which is confirmed by a difference of one trophic level between filter feeders and carnivores, according to stable N isotope enrichment data.
Peer review: yes
DOI: 10.1093/plankt/fbv037
ISSN: 0142-7873
Appears in Collections:CESAM - Artigos
DBio - Artigos

Files in This Item:
File Description SizeFormat 
Molina-Ramirez et al. - 2015 - Functional differences in the allometry of the wat.pdf332.5 kBAdobe PDFrestrictedAccess

Formato BibTex MendeleyEndnote Degois 

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.