Supplementary Table 1 – Different approaches to calculating reef carbonate budgets and the merits/limitations of resultant outputs.

Method / Resultant data / References
Hydrochemical data - derived from measured changes in pH and total alkalinity of the water above a reef. Measures are A sum of total carbonate precipitation (by benthic calcifiers, including sediment producers, and cements) and carbonate dissolution. / Provide measures of net carbonate production, but do not allow differentiation of production by different calcifiers/carbonate producing process, and are complex to apply where significant water mixing occurs. / Smith and Kinsey 1976
Kinsey 1985
Census-based estimates - organism/process-based and derive from measures of biota cover and growth rates, and of substrate biological erosion. / Method provides data on the relative contributions made by individual biological producers and eroders, but does not readily (or reliably) account for carbonate added or removed through lithification or dissolution. / Chave et al. 1972
Eakin 1996
Harney & Fletcher 2003
Scoffin et al. 1980
Stearn et al. 1977
Net accumulation rates - calculated from long-term sediment accumulation rates and on the carbonate content of that sediment. / Measures reflect long-term net rates of production and integrate syn- and post-depositional carbonate dissolution and erosion, but do not differentiate between processes. / Land 1979
Hubbard et al. 1990

Refs:

ChaveKS, Smith SV, Roy K (1972) Carbonate production by coral reefs. Mar Geol 12: 123–140

Eakin C (1996) Where have all the carbonates gone? A model comparison of calcium carbonate budgets before and after the 1982-1983 El Nino at UvaIsland in the eastern Pacific. Coral Reefs 15: 109–119

Harney JN, Fletcher III CH (2003) A budget of carbonate framework and sediment production, KailuaBay, Oahu, Hawaii. J Sediment Res 73: 856–868

Hubbard D, Miller A, Scaturo D (1990) Production and cycling of calcium carbonate in a shelf-edge reef system (St. Croix, US Virgin Islands): applications to the nature of reef systems in the fossil record. J Sediment Petrol 60: 335–360

Kinsey DW (1985) Metabolism, calcification and carbonate production: I. Systems level studies. Proc 5th Coral Reef Symp 1: 505– 526

Land LS (1979) The fate of reef-derived sediment on the north Jamaican island slope. Mar Geol 29: 55–71

Scoffin T, Stearn C, Boucher D, Frydl P, Hawkins CM, Hunter IG, MacGeachy JK (1980) Calcium carbonate budget of a fringing reef on the west coast of Barbados. I. Erosion, sediments and internal structure. Bull Mar Sci 30: 475–508

Smith SV, Kinsey DW (1976) Calcium carbonate production, coral reef growth, and sea level change. Science 194: 937– 939

Stearn CW, Scoffin TP, Martindale W (1977) Calcium carbonate budget of a fringing reef on the west coast of Barbados. Part 1 – Zonation and productivity. Bull Mar Sci 27: 479–510