Seawater carbonate chemistry, structural and chemical characteristics of the seagrass Thalassia testudinum in an situ CO2 enrichment experiment, supplement to: Campbell, Justin E; Fourqurean, James W (2013): Effects of in situ CO2 enrichment on the structural and chemical characteristics of the seagrass Thalassia testudinum. Marine Biology, 160(6), 1465-1475

• Main Authors: Campbell, Justin E, Fourqurean, James W
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2013
• Subjects: Benthos; Coast and continental shelf; Containers and aquaria 20-1000 L or < 1 m**2; Field experiment; Growth/Morphology; North Atlantic; Plantae; Seagrass; Single species; Temperate; Thalassia testudinum; Tracheophyta; Identification; Species; Treatment; Incubation duration; Standing crop, vegetation; Standing crop, vegetation, standard error; Mass per shoot; Mass per shoot, standard error; Shoot density; Shoot density, standard error; Leaf area per shoot; Leaf area per shoot, standard error; Leaf, growth rate; Leaf, growth rate, standard error; Nitrogen/Phosphorus ratio; Nitrogen/Phosphorus ratio, standard error; Carbon/Phosphorus ratio; Carbon/Phosphorus ratio, standard error; Carbon/Nitrogen ratio; Carbon/Nitrogen ratio, standard error; Position; Carbohydrates, non structural; Carbohydrates, non structural, standard error; Temperature, water; Salinity; Alkalinity, total; pH; Carbon, inorganic, dissolved; Carbon dioxide; Bicarbonate ion; Carbonate ion; Carbonate system computation flag; Partial pressure of carbon dioxide water at sea surface temperature wet air; Fugacity of carbon dioxide water at sea surface temperature wet air; Aragonite saturation state; Calcite saturation state; Experiment; Onset logger; Potentiometric titration; Potentiometric; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.824407; https://doi.pangaea.de/10.1594/PANGAEA.824407

Seagrasses commonly display carbon-limited photosynthetic rates. Thus, increases in atmospheric pCO2, and consequentially oceanic CO2(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 CO2(aq) enrichment on the structural and chemical characteristics of the tropical seagrass, Thalassia testudinum. CO2(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 CO2(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 CO2(aq) availability may primarily alter the chemical composition of seagrasses, influencing both the nutrient status and resilience of these systems. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Lavigne and Gattuso, 2011) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2013-12-10.