CoralNet now has the capacity to estimate benthic carbonate production from image annotations. Commonly used metrics of coral cover and overall coral community composition provide useful insights into overall coral reef condition. However, differences in calcification rates between coral taxa and availability of exposed substrate to macrobioerosion and microbioerosion can generate considerable differences in the ability for coral reefs to build and maintain their calcium carbonate structures, which provide many of the key ecosystem services that coral reefs provide. CoralNet now has the capacity to estimate this critical function of coral reef building automatically from annotated coral reef images.
To accomplish this task, we have developed area-normalized calcification, macrobioerosion, and microbioerosion rates from the ReefBudget methodology [1,2] for many commonly used CoralNet labels throughout the Indo-Pacific and Atlantic regions [3]. All code, data, and methodologies used to scale these default rate tables are publicly accessible [3]. These rates are then applied to the relative benthic cover within each image following simplified ReefBudget methodologies [1,2] to estimate coral reef carbonate production rates. Just look for the blue “C” next to the label to see if calcification rates are available when selecting image labels for image annotation.
The default rates include both calcification and macro- and microbioerosion; however, the code and data release includes optional tables to estimate benthic calcification without any consideration of macro- or micro-bioerosion [3]. The rate tables can be downloaded, modified, and replaced with uploaded customized rate tables to allow for site-specific rates to be applied to your image annotation projects. Additionally, the optional columns to include per-label contributions to the mean rate and to the confidence bounds can be selected to show the net carbonate production for each label within each image (e.g. 4 labels = adds 4 columns for the mean rate for each label and adds 2x4=8 columns for the upper and lower confidence bounds for each label in the below screenshot).
Please see the latest tutorial to learn more about how to integrate estimates of coral reef carbonate production into your CoralNet image annotation projects: https://coralnet.ucsd.edu/pages/help/tutorials/calcification/
Let us know if you’d like calcification and/or macro- and microbioerosion rates to be expanded for any additional labels and we can work to include this in subsequent updates to the provided default rate tables.
The addition of coral carbonate production estimates to CoralNet was graciously made possible by a grant awarded to Andreas Andersson (SIO-UCSD) and David Kriegman (UCSD) by the NOAA Ocean Acidification Program and implemented by Travis Courtney (SIO-UCSD) and Stephen Chan (UCSD).
Bibliography
[1] Perry CT and Lange ID (2019) ReefBudget Caribbean v2: online resource and methodology. Retrieved from http://geography.exeter.ac.uk/reefbudget/
[2] Perry CT, Lange I, Januchowski-Hartley FA (2018) ReefBudget Indo Pacific: online resource and methodology. Retrieved from http://geography.exeter.ac.uk/reefbudget/
[3] Courtney TA, Chan S, Lange ID, Perry CT, Kriegman DJ, Andersson AJ (2021) Area-normalized scaling of ReefBudget calcification, macrobioerosion, and microbioerosion rates for use with CoralNet Version 1.0 https://doi.org/10.5281/zenodo.5140477