Effects of ocean acidification on Posidonia oceanica epiphytic community and shoot productivity

  1. Biological interactions can alter predictions that are based on single-species physiological response. It is known that leaf segments of the seagrass Posidonia oceanica will increase photosynthesis with lowered pH, but it is not clear whether the outcome will be altered when the whole plant and its epiphyte community, with different respiratory and photosynthetic demands, are included. In addition, the effects on the Posidonia epiphyte community have rarely been tested under controlled conditions, at near-future pH levels.
  2. In order to better evaluate the effects of pH levels as projected for the upcoming decades on seagrass meadows, shoots of P. oceanica with their associated epiphytes were exposed in the laboratory to three pH levels (ambient: 8.1, 7.7 and 7.3, on the total scale) for 4 weeks. Net productivity, respiration, net calcification and leaf fluorescence were measured on several occasions. At the end of the study, epiphyte community abundance and composition, calcareous mass and crustose coralline algae growth were determined. Finally, photosynthesis vs. irradiance curves (PE) was produced from segments of secondary leaves cleaned of epiphytes and pigments extracted.
  3. Posidonia leaf fluorescence and chlorophyll concentrations did not differ between pH treatments. Net productivity of entire shoots and epiphyte-free secondary leaves increased significantly at the lowest pH level yet limited or no stimulation in productivity was observed at the intermediate pH treatment. Under both pH treatments, significant decreases in epiphytic cover were observed, mostly due to the reduction of crustose coralline algae. The loss of the dominant epiphyte producer yet similar photosynthetic response for epiphyte-free secondary leaves and shoots suggests a minimal contribution of epiphytes to shoot productivity under experimental conditions.
  4. Synthesis. Observed responses indicate that under future ocean acidification conditions foreseen in the next century an increase in Posidonia productivity is not likely despite the partial loss of epiphytic coralline algae which are competitors for light. A decline in epiphytic cover could, however, reduce the feeding capacity of the meadow for invertebrates. In situ long-term experiments that consider both acidification and warming scenarios are needed to improve ecosystem-level predictions.

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Cite this as

Cox, T Erin, Schenone, Stefano, Delille, Jeremy, Díaz-Castañeda, Victoria, Alliouane, Samir, Gattuso, Jean-Pierre, Gazeau, Frédéric (2015). Dataset: Effects of ocean acidification on Posidonia oceanica epiphytic community and shoot productivity. https://doi.org/10.1594/PANGAEA.859956

DOI retrieved: 2015

Additional Info

Field Value
Imported on November 30, 2024
Last update November 30, 2024
License CC-BY-3.0
Source https://doi.org/10.1594/PANGAEA.859956
Author Cox, T Erin
Given Name T Erin
Family Name Cox
More Authors
Schenone, Stefano
Delille, Jeremy
Díaz-Castañeda, Victoria
Alliouane, Samir
Gattuso, Jean-Pierre
Gazeau, Frédéric
Source Creation 2015
Publication Year 2015
Resource Type text/tab-separated-values - filename: Cox_2016
Subject Areas
Name: BiologicalClassification

Name: Chemistry

Name: Ecology

Related Identifiers
Title: Effects of ocean acidification on Posidonia oceanica epiphytic community and shoot productivity
Identifier: https://doi.org/10.1111/1365-2745.12477
Type: DOI
Relation: IsSupplementTo
Year: 2015
Source: Journal of Ecology
Authors: Cox T Erin , Schenone Stefano , Delille Jeremy , Díaz-Castañeda Victoria , Alliouane Samir , Gattuso Jean-Pierre , Gazeau Frédéric .

Title: seacarb: seawater carbonate chemistry with R. R package version 3.0.8
Identifier: https://cran.r-project.org/package=seacarb
Type: DOI
Relation: References
Year: 2015
Authors: Gattuso Jean-Pierre , Epitalon Jean-Marie , Lavigne Héloïse .