Open Access Repository

Remnant kelp bed refugia and future phase-shifts under ocean acidification


Downloads per month over past year

Ling, SD ORCID: 0000-0002-5544-8174, Cornwall, CE ORCID: 0000-0002-6154-4082, Tilbrook, Bronte and Hurd, CL ORCID: 0000-0001-9965-4917 2020 , 'Remnant kelp bed refugia and future phase-shifts under ocean acidification' , PLoS ONE, vol. 15, no. 10 , pp. 1-16 , doi: 10.1371/journal.pone.0239136.

141493 - Remnan...pdf | Download (2MB)

| Preview


Ocean warming, ocean acidification and overfishing are major threats to the structure and function of marine ecosystems. Driven by increasing anthropogenic emissions of CO2, ocean warming is leading to global redistribution of marine biota and altered ecosystem dynamics, while ocean acidification threatens the ability of calcifying marine organisms to form skeletons due to decline in saturation state of carbonate Ω and pH. In Tasmania, the interaction between overfishing of sea urchin predators and rapid ocean warming has caused a phase-shift from productive kelp beds to overgrazed sea urchin barren grounds, however potential impacts of ocean acidification on this system have not been considered despite this threat for marine ecosystems globally. Here we use automated loggers and point measures of pH, spanning kelp beds and barren grounds, to reveal that kelp beds have the capacity to locally ameliorate effects of ocean acidification, via photosynthetic drawdown of CO2, compared to unvegetated barren grounds. Based on meta-analysis of anticipated declines in physiological performance of grazing urchins to decreasing pH and assumptions of nil adaptation, future projection of OA across kelp-barrens transition zones reveals that kelp beds could act as important pH refugia, with urchins potentially becoming increasingly challenged at distances >40 m from kelp beds. Using spatially explicit simulation of physicochemical feedbacks between grazing urchins and their kelp prey, we show a stable mosaicked expression of kelp patches to emerge on barren grounds. Depending on the adaptative capacity of sea urchins, future declines in pH appear poised to further alter phase-shift dynamics for reef communities; thus, assessing change in spatial-patterning of reef-scapes may indicate cascading ecological impacts of ocean acidification.

Item Type: Article
Authors/Creators:Ling, SD and Cornwall, CE and Tilbrook, Bronte and Hurd, CL
Keywords: kelp forest, temperate reefs, ocean acidification, climate change, ocean warming, phase-shift, alternative stable states, regime-shift, landscape ecology, overgrazing, sea urchin
Journal or Publication Title: PLoS ONE
Publisher: Public Library of Science
ISSN: 1932-6203
DOI / ID Number: 10.1371/journal.pone.0239136
Copyright Information:

Copyright 2020 Ling et al. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0)

Related URLs:
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page