Corals growth rate

Edinger, E. N., Limmon, G. V., Jompa, J., Widjatmoko, W., Heikoop, J. M., and Risk, M.J. (2000). Normal coral growth rates on dying reefs Are coral growth rates good indicators of reef health Mar. Pollut. Bull. 5, 404—425. 

Clausen, C.D. and Roth, A.A., 1975. Estimation of coral growth rates from laboratory Ca-incorporation rates. Mar. Biol., 33 85—91. 

Figure 116. Coral growth rates using Ra and (a) Longitudinal sectional view of the coral...

Chrost, R. J. and M. A. Faust. 1999. Consequences of solar radiation on bacterial secondary production and growth rates in subtropical coastal water (Atlantic Coral Reef off Belize, Central America). Aquatic Microbial Ecology 20 39-48. 

Buddemeier, R.W., Maragos, J.E. and Knutson, D.W., 1974. Radiographic studies of coral reef exoskeletons Rates and patterns of coral growth. J. Exp. Mar. Biol. Ecol., 14 179—200. 

Moore, W.S. and Krishnaswami, S., 1974. Correlation of x-radiography revealed banding in corals with radiometric growth rates. Proc. Second Internat. Symp. on Coral Reefs, Great Barrier Reef Committee, Brisbane, 2 269—276. 

Land, L.S., 1974. Growth rate of a West Indian (Jamaican) reef. Proceedings of the Second International Symposium on Coral Reefs, Vol. 2, pp. 409—412,... 

The agreement between ages based on radioactivity inclusions and those determined by density band counting encourages us to measure growth rates on the basis of density bands in those corals which do not contain radioactivity. 

Stephanocoenia sp.) collected from Discovery Bay, Jamaica. Branching at about 25 cm from the top is clearly evident. Samples analyzed are designated with a letter and number, (b) Plot of activity of Ra/ Ra in the Jamaica coral head and the North Carolina coral (Solenastrea hyades) head vs. distance from outer surface. The estimated growth rates based on decay of excess Ra activity are 0.5 and 0.15 cm/yr, respectively. From Moore and Krishnaswami (1972). 

Moore and Krishnaswami (1972) studied the growth rate of head corals (Stephanocoenia sp. and Solenastrea hyades) by two radiometric methods. Assuming an initial incorporation of Ra (or b) to Ra, which has a long half-life (1600 years) as contrasted to Ra and Pb, they used the decay of the latter in the coral as an index of growth rate. Since Ra has a shorter half-life (5.77 years) than Pb (21 years), the presence of Ra would approach zero in the older areas of the coral, and if no additional material was incorporated into the coral, it would be measurable for about 30 years. The Pb would reach equilibrium with its parent, Ra, in older sections of the coral head. Figure 116 shows the procedure for sampling a coral head and the graphic results of the 2 Ra/ Ra ratio method. 

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