Dataset: Coral calcification (G) from six sites on the south coast of St. John, USVI from 1992 to 2019

Final no updates expectedDOI: 10.26008/1912/bco-dmo.897564.1Version 1 (2023-06-14)Dataset Type:Other Field Results

Principal Investigator: Peter J. Edmunds (California State University Northridge)

Scientist: Chris T. Perry (University of Exeter)

BCO-DMO Data Manager: Amber D. York (Woods Hole Oceanographic Institution)


Project: LTREB Long-term coral reef community dynamics in St. John, USVI: 1987-2019 (St. John LTREB)

Project: RAPID: Hurricane Irma: Effects of repeated severe storms on shallow Caribbean reefs and their changing ecological resilience (Hurricane Irma and St. John Reefs)

Project: RUI-LTREB Renewal: Three decades of coral reef community dynamics in St. John, USVI: 2014-2019 (RUI-LTREB)

Project: RUI: Pattern and process in four decades of change on Caribbean reefs (St John Coral Reefs)


Abstract

These data describe coral calcification (G) from 1992-2019 at six sites on the south coast of St. John. G was calculated from ReefBudget using coral density and size by taxon and quadrat. These data were published in Edmunds and Perry (2023).

Coral community calcification (G, kg CaCO3 m-2 yr-1) by site and year was calculated based on colony sizes that were measured as described above and used to calculate G summed by photoquadrat (i.e., photoquadrats were treated as statistical replicates). In the formulation applied herein, G provides an estimate of gross coral calcification, as we do not consider any source of dissolution and bioerosion. G is not equivalent to NCC because dissolution/bioerosion is not considered, and we do not evaluate calcification by taxa other than corals. First, the mean diameters of each coral colony in each quadrat (i.e., the mean colony diameter in planar view), were used to estimate the 3-dimensional colony size (i.e., the actual size of living tissue) based on taxon-specific rugosity for Caribbean corals (Equation 1, see supplemental file "Coral Calcification Equations"). Actual tissue cover was required to accurately estimate colony-level calcification, because coral species differ in their 3-D shapes, which affects G depending on colony morphology.

See Equations in supplemental pdf file "Coral Calcification Equations".

The annual calcification (kg colony-1 yr-1) of corals in each photoquadrat was calculated by summing the CPi values by taxon. Values were standardized to a square meter to be consistent with a commonly used unit of G, kg CaCO3 m-2 yr-1, which can be converted to other units through stoichiometry (e.g., 1 kg CaCO3 m-2 yr-1 = 27.4 mmol CaCO3 m-2 d-1). In our calculations we assume that coral calcification rates are uniform with colony size (i.e., isometric). Work in Moorea has shown that some colony calcification rates increase rapidly up until colonies are ~10–15 cm diameter, but our assumption of isometry is currently necessary for Caribbean corals as the data necessary to parameterize the relationship between colony size and coral calcification currently is lacking for the corals in this region. However, given that nearly all colonies in our study are small (averaging < 6 cm) and remain small due to high demographic turnover, the use of taxon-specific calcification (i.e., independent of colony size) rate is less problematic than would be the case in Moorea. Our assumption of isometric coral calcification may render a conservative bias in our calculations of coral G. Using photoquadrats as statistical replicates, coral G (pooled among taxa) was compared among sites and years (Hypothesis 2) using a mixed effects, two way ANOVA in which site was a random effect, year was a fixed effect, and G was log(x +1) transformed to meet the assumptions of the statistical test. G was also averaged by site and year using values pooled among taxa and also by taxon, and the values were qualitatively compared over time for each site. They were also used to assess whether the taxa contributing to coral G varied within- or among- sites as a function of coral community composition and colony size.

Location: South coast of St. John, US Virgin Islands. 18.31644, -64.724528. Research conducted during annual field expeditions to research lab: The Virgin Islands Ecological Research Station.

Data come from six sites (Cabritte Horn, East Tektite, Neptune's Table, West Little Lameshur Bay, Europa Bay, White Point. ) between White Point and Cabritte Horn.  See supplemental file "Site List" for site names and locations as well as the site map (Fig. 1 of Edmunds, 2013).

Problems/Issues: Some irregular number of quadrats were samples at some sites in some years.

Funding note:  The most recent funding for this time series was provided by NSF award OCE-2019992 for project "RUI: Pattern and process in four decades of change on Caribbean reefs."  The "Project" and "Funding Sources" sections of this page list also include past awards that directly funded this dataset.


Related Datasets

IsRelatedTo

Dataset: Coral cover from 1992-2019 in support of Edmunds and Perry (2023) MEPS
Relationship Description: Datasets collected as part of the same study and support Edmunds and Perry (2023, doi: 10.3354/meps14345).
Edmunds, P. J., Perry, C. T. (2023) Coral cover at six sites on the south coast of St. John, USVI from 1992 to 2019. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2023-06-14 doi:10.26008/1912/bco-dmo.897544.1
IsRelatedTo

Dataset: Coral colony densities from 1992-2019 in support of Edmunds and Perry (2023) MEPS
Relationship Description: Datasets collected as part of the same study and support Edmunds and Perry (2023, doi: 10.3354/meps14345).
Edmunds, P. J., Perry, C. T. (2023) Coral density from six sites on the south coast of St. John, USVI from 1992 to 2019. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2023-06-14 doi:10.26008/1912/bco-dmo.897577.1
IsRelatedTo

Dataset: Coral sizes in support of Edmunds and Perry (2023) MEPS
Relationship Description: Datasets collected as part of the same study and support Edmunds and Perry (2023, doi: 10.3354/meps14345).
Edmunds, P. J., Perry, C. T. (2023) Coral sizes from six sites on the south coast of St. John, USVI from 1992 to 2019. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2023-06-14 doi:10.26008/1912/bco-dmo.897571.1
IsSupplementedBy

Dataset: Coral photransect and settlement tile images from St. John, USVI 1987-2019
Relationship Description: Supporting images for this dataset.
Edmunds, P. J. (2023) Coral photransect and settlement tile images from St. John, USVI 1987-2019. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2023-06-30 http://lod.bco-dmo.org/id/dataset/897659

Related Publications

Results

Edmunds, P., & Perry, C. (2023). Decadal-scale variation in coral calcification on coral-depleted Caribbean reefs. Marine Ecology Progress Series. https://doi.org/10.3354/meps14345
Methods

Edmunds, P. (2013). Decadal-scale changes in the community structure of coral reefs of St. John, US Virgin Islands. Marine Ecology Progress Series, 489, 107–123. doi:10.3354/meps10424
Software

Perry CT, Lange ID (2019) ReefBudget Caribbean v2: online resource and methodology. Retrieved from http://geography.exeter.ac.uk/reefbudget/