2024-03-19T07:15:36Z
https://tsukuba.repo.nii.ac.jp/oai
oai:tsukuba.repo.nii.ac.jp:00057091
2022-04-27T09:32:50Z
160:7932
3:62:5595:8323
Novel reverse radioisotope labelling experiment reveals carbon assimilation of marine calcifiers under ocean acidification conditions
西田, 梢
ニシダ, コズエ
NISHIDA, Kozue
CHEW, Yue Chin
MIYAIRI, Yosuke
HIRABAYASHI, Shoko
SUZUKI, Atsushi
HAYASHI, Masahiro
YAMAMOTO, Yuzo
SATO, Mizuho
NOJIRI, Yukihiro
YOKOYAMA, Yusuke
© 2020 The Authors. Methods in Ecology and Evolution published by John Wiley & Sons Ltd on behalf of British Ecological Society This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
1. Ocean acidification by anthropogenic carbon dioxide emissions is projected to depress metabolic and physiological activity in marine calcifiers. To evaluate the sensitivity of marine organisms against ocean acidification, the assimilation of nutrients into carbonate shells and soft tissues must be examined.
2. We designed a novel experimental protocol, reverse radioisotope labelling, to trace partitioning of nutrients within a single bivalve species under ocean acidification conditions. Injecting CO2 gas, free from radiocarbon, can provide a large contrast between carbon dissolved in the water and the one assimilated from atmosphere. By culturing modern aquifer organisms in acidified seawater, we were able to determine differences in the relative contributions of the end members, dissolved inorganic carbon (DIC) in seawater and metabolic CO2, to shell carbonate and soft tissues.
3. Under all pCO2 conditions (463, 653, 872, 1,137 and 1,337 μatm), radiocarbon (Δ14C) values of the bivalve Scapharca broughtonii shell were significantly correlated with seawater DIC values; therefore, shell carbonate was derived principally from seawater DIC. The Δ14C results together with stable carbon isotope (δ13C) data suggest that in S. broughtonii shell δ13C may reflect the kinetics of isotopic equilibration as well as end‐member contributions; thus, care must be taken when analysing end‐member contributions by a previous method using δ13C. The insensitivity of S. broughtonii to perturbations in pCO2 up to at least 1,337 µatm indicates that this species can withstand ocean acidification.
4. Usage of radioisotope to dope for tracer experiments requires strict rules to conduct any operations. Yet, reverse radioisotope labelling proposing in this study has a large advantage and is a powerful tool to understanding physiology of aquifer organisms that can be applicable to various organisms and culture experiments, such as temperature, salinity and acidification experiments, to improve understanding of the proportions of nutrients taken in by marine organisms under changing environments.
British Ecological Sciety
John Wiley & Sons
2020-06
eng
journal article
http://hdl.handle.net/2241/00162741
https://tsukuba.repo.nii.ac.jp/records/57091
10.1111/2041-210X.13396
2041-210X
Methods in Ecology and Evolution
11
6
739
750
https://tsukuba.repo.nii.ac.jp/record/57091/files/MEE_11-6-739.pdf
application/pdf
1.3 MB
2021-02-16