eCite Digital Repository

Saturating light and not increased carbon dioxide under ocean acidification drives photosynthesis and growth in Ulva rigida (Chlorophyta)


Rautenbuerger, R and Fernandez, PA and Strittmatter, M and Heesch, S and Cornwall, CE and Hurd, CL and Roleda, MY, Saturating light and not increased carbon dioxide under ocean acidification drives photosynthesis and growth in Ulva rigida (Chlorophyta), Ecology and Evolution, 5, (4) pp. 874-888. ISSN 2045-7758 (2015) [Refereed Article]


Copyright Statement

Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0)

DOI: doi:10.1002/ece3.1382


Carbon physiology of a genetically identified Ulva rigida was investigated under different CO2(aq) and light levels. The study was designed to answer whether (1) light or exogenous inorganic carbon (Ci) pool is driving growth; and (2) elevated CO2(aq) concentration under ocean acidification (OA) will downregulate CAext-mediated inline image dehydration and alter the stable carbon isotope (δ13C) signatures toward more CO2 use to support higher growth rate. At pHT 9.0 where CO2(aq) is <1 μmol L−1, inhibition of the known inline image use mechanisms, that is, direct inline image uptake through the AE port and CAext-mediated inline image dehydration decreased net photosynthesis (NPS) by only 56–83%, leaving the carbon uptake mechanism for the remaining 17–44% of the NPS unaccounted. An in silico search for carbon-concentrating mechanism elements in expressed sequence tag libraries of Ulva found putative light-dependent inline image transporters to which the remaining NPS can be attributed. The shift in δ13C signatures from –22‰ toward –10‰ under saturating light but not under elevated CO2(aq) suggest preference and substantial inline image use to support photosynthesis and growth. U. rigida is Ci saturated, and growth was primarily controlled by light. Therefore, increased levels of CO2(aq) predicted for the future will not, in isolation, stimulate Ulva blooms.

Item Details

Item Type:Refereed Article
Keywords:Ulva, ocean acidification, seaweed, carbon dioxide, photosynthesis, physiological ecology
Research Division:Environmental Sciences
Research Group:Climate change impacts and adaptation
Research Field:Ecological impacts of climate change and ecological adaptation
Objective Division:Environmental Policy, Climate Change and Natural Hazards
Objective Group:Adaptation to climate change
Objective Field:Ecosystem adaptation to climate change
UTAS Author:Cornwall, CE (Dr Chris Cornwall)
UTAS Author:Hurd, CL (Professor Catriona Hurd)
ID Code:100168
Year Published:2015
Web of Science® Times Cited:65
Deposited By:IMAS Research and Education Centre
Deposited On:2015-05-06
Last Modified:2017-10-31
Downloads:398 View Download Statistics

Repository Staff Only: item control page