Document Detail

Using stable isotopes to assess carbon and nitrogen turnover in the Arctic sympagic amphipod Onisimus litoralis.
MedLine Citation:
PMID:  18709389     Owner:  NLM     Status:  MEDLINE    
Food web studies based on stable C and N isotope ratios usually assume isotopic equilibrium between a consumer and its diet. In the Arctic, strong seasonality in food availability often leads to diet switching, resulting in a consumer's isotopic composition to be in flux between different food sources. Experimental work investigating the time course and dynamics of isotopic change in Arctic fauna has been lacking, although these data are crucial for accurate interpretation of food web relationships. We investigated seasonal (ice-covered spring vs. ice-free summer) and temperature (1 vs. 4 degrees C) effects on growth and stable C and N isotopic change in the common nearshore Arctic amphipod Onisimus litoralis following a diet switch and while fasting in the laboratory. In spring we found no significant temperature effect on N turnover [half-life (HL) estimates: HL-N = 20.4 at 4 degrees C, 22.4 days at 1 degrees C] and a nonsignificant trend for faster growth and C turnover at the higher temperature (HL-C = 13.9 at 4 degrees C, 18.7 days at 1 degrees C). A strong seasonal effect was found, with significantly slower growth and C and N turnover in the ice-free summer period (HL-N = 115.5 days, HL-C = 77.0 days). Contrary to previous studies, metabolic processes rather than growth accounted for most of the change in C and N isotopic composition (84-89 and 67-77%, respectively). This study provides the first isotopic change and metabolic turnover rates for an Arctic marine invertebrate and demonstrates the risk of generalizing turnover rates based on taxon, physiology, and environment. Our results highlight the importance of experimental work to determine turnover rates for species of interest.
Mette R Kaufman; Rolf R Gradinger; Bodil A Bluhm; Diane M O'Brien
Related Documents :
11676459 - Effect of environment on the free and peptide amino acids in rice, wheat, and soybeans.
11082059 - Regional changes in carbon dioxide fluxes of land and oceans since 1980.
16688169 - Seawater subduction controls the heavy noble gas composition of the mantle.
15959509 - Widespread magma oceans on asteroidal bodies in the early solar system.
21844279 - Integration: valuing stakeholder input in setting priorities for socially sustainable e...
18723639 - Nutritional role of two algal symbionts in the temperate sea anemone anthopleura elegan...
10645349 - Study of diffusion through ldpe film of di-n-butyl phthalate.
15621069 - Apolipoprotein a-iv, food intake, and obesity.
20708659 - Dogs choose a human informant: metacognition in canines.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2008-08-16
Journal Detail:
Title:  Oecologia     Volume:  158     ISSN:  0029-8549     ISO Abbreviation:  Oecologia     Publication Date:  2008 Nov 
Date Detail:
Created Date:  2008-10-07     Completed Date:  2009-04-07     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0150372     Medline TA:  Oecologia     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  11-22     Citation Subset:  IM    
School of Fisheries and Ocean Sciences, University of Alaska, Fairbanks, 245 O'Neill Building, Fairbanks, AK, 99775, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Algae / metabolism*
Amphipoda / growth & development,  metabolism*
Arctic Regions
Carbon / metabolism*
Carbon Isotopes / metabolism
Food Chain
Ice Cover
Nitrogen / metabolism*
Nitrogen Isotopes / metabolism
Reg. No./Substance:
0/Carbon Isotopes; 0/Nitrogen Isotopes; 7440-44-0/Carbon; 7727-37-9/Nitrogen

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Life cycle polyphenism as a factor affecting ecological divergence within Notophthalmus viridescens.
Next Document:  Genetic forms of nephrotic syndrome: a single-center experience in Brussels.