Production of Carbonate Sediments by Selected Large Benthic Foraminifera on Two Pacific Coral Reefs

Abstract

ABSTRACT Carbonate production, deposition, and turnover rates by selected members of the rotaliine foraminiferal families Asterigerinidae, Calcarinidae, and Nummulitidae were calculated using growth and standing crop data. In Palau, Western Caroline Islands, carbonate production rates on seaward reef flats were up to 2.8 kg CaCO3 m-2 yr-1, which is equivalent to carbonate deposition of almost 1 mm yr-1. Productivity on lagoonal reef slopes was about 0.6 kg CaCO3 m-2 yr-1 or deposition of about 0.2 mm yr-1. Carbonate turnover rates in the living populations were 11-16 times per year. In Hawaii, production rates were much lower because of slower growth rates and the absence of the family Calcarinidae. Product on rates were up to 0.15 kg CaCO3 m-2yr-1 on seaward reef slopes, which is a depositional rate of about 0.05 mm yr-1. Carbonate turnover rates were 7-11 times per year. These production rates are comparable to many values reported in the literature for coral, coralline algae, and macrobenthos.