Seawater carbonate chemistry and carbonate load of seagrass leaves

• Main Authors: Mazarrasa, Inés, Marbà, Núria, Krause-Jensen, Dorte, Kennedy, Hilary, Santos, Rui, Lovelock, Catherine E, Duarte, Carlos Manuel
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2019
• Subjects: Benthos; Calcification/Dissolution; Coast and continental shelf; Field observation; Growth/Morphology; Heterozostera tasmanica; Indian Ocean; North Atlantic; Plantae; Seagrass; Single species; South Pacific; Temperate; Tracheophyta; Zostera capricorni; Zostera marina; Event label; Type; Species; Registration number of species; Uniform resource locator/link to reference; Site; LATITUDE; LONGITUDE; Shoots; Number of leaves; Surface area; Mass per shoot; Carbonate ion; Carbonate mass per shoot; Calcification rate; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Replicates; Alkalinity, total; Alkalinity, total, standard deviation; pH; pH, standard deviation; Salinity; Salinity, standard deviation; Temperature, water; Temperature, water, standard deviation; Calcite saturation state; Calcite saturation state, standard deviation; Aragonite saturation state; Aragonite saturation state, standard deviation; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Experiment; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Indian; Pacific; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.926679; https://doi.pangaea.de/10.1594/PANGAEA.926679

Seagrass meadows play a significant role in the formation of carbonate sediments, serving as a substrate for carbonate-producing epiphyte communities. The magnitude of the epiphyte load depends on plant structural and physiological parameters, related to the time available for epiphyte colonization. Yet, the carbonate accumulation is likely to also depend on the carbonate saturation state of seawater (Omega) that tends to decrease as latitude increases due to decreasing temperature and salinity. A decrease in carbonate accumulation with increasing latitude has already been demonstrated for other carbonate producing communities. The aim of this study was to assess whether there was any correlation between latitude and the epiphyte carbonate load and net carbonate production rate on seagrass leaves. Shoots from 8 different meadows of the Zostera genus distributed across a broad latitudinal range (27 °S to up to 64 °N) were sampled along with measurements of temperature and Omega. The Omega within meadows significantly decreased as latitude increased and temperature decreased. The mean carbonate content and load on seagrass leaves ranged from 17 % DW to 36 % DW and 0.4-2.3 mg CO3/cm**2, respectively, and the associated mean carbonate net production rate varied from 0.007 to 0.9 mg CO3/cm**2/d. Mean carbonate load and net production rates decreased from subtropical and tropical, warmer regions towards subpolar latitudes, consistent with the decrease in Omega. These results point to a latitudinal variation in the contribution of seagrass to the accumulation of carbonates in their sediments which affect important processes occurring in seagrass meadows, such as nutrient cycling, carbon sequestration and sediment accretion. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2020) 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 2020-12-25.