Title

Effects of In Situ CO2 Enrichment on the Structural and Chemical Characteristics of the Seagrass Thalassia Testudinum

Authors

Justin E. Campbell, Marine Science Program, Department of Biological Sciences and Southeast Environmental Research Center, Florida International University; Smithsonian Marine StationFollow
Henry O. Briceño, Justin E Campbell , Marine Science Program, Department of Biological Sciences and Southeast Environmental Research Center, Florida International UniversityFollow

Abstract

Seagrasses commonly display carbon-limited photosynthetic rates. Thus, increases in atmospheric pCO₂, and consequentially oceanic CO_2(aq) concentrations, may prove beneficial. While addressed in mesocosms, these hypotheses have not been tested in the field with manipulative experimentation. This study examines the effects of in situ CO_2(aq) enrichment on the structural and chemical characteristics of the tropical seagrass, Thalassia testudinum. CO_2(aq) availability was manipulated for 6 months in clear, open-top chambers within a shallow seagrass meadow in the Florida Keys (USA), reproducing forecasts for the year 2100. Structural characteristics (leaf area, leaf growth, shoot mass, and shoot density) were unresponsive to CO_2(aq) enrichment. However, leaf nitrogen and phosphorus content declined on average by 11 and 21 %, respectively. Belowground, non-structural carbohydrates increased by 29 %. These results indicate that increased CO_2(aq) availability may primarily alter the chemical composition of seagrasses, influencing both the nutrient status and resilience of these systems.

Comments

The definitive publisher-authenticated version is available online at http://dx.doi.org/10.1007/s00227-013-2199-3

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Recommended Citation

Campbell, J.E., J.W. Fourqurean. 2013. Effects of in situ CO2 enrichment on the structural and chemical characteristics of the seagrass Thalassia testudinum . Marine Biology 160(6): 1465-1475. DOI: 10.1007/s00227-013-2199-3