A COMPARISON OF METHODS FOR THE ACCURATE MEASUREMENT OF EPIPHYTIC CARBONATE

The accurate measurement of epiphytic carbonate is vital in the constr uction of carbonate budgets. Prior studies have produced estimates of epiphytic carbonate production, but the results of these investigation s are not directly comparable due to the variety of methods employed b y the investigators. This investigation field-tested four methods of m easuring epiphytic carbonate. These four methods were the gravimetric leaf acidification technique, the EDTA titration of epiphytized leaves , the EDTA titration with seagrass blanks, and the scrape and titrate method. The leaf acidification method and the EDTA titrimetric method without seagrass blanks resulted in significantly larger estimates of epiphytic carbonate than those produced using the other two methods. I t is believed that the leaf acidification technique and the EDTA titra tion of epiphytized leaves results in overestimates of epiphytic carbo nate due to the leaching of organic matter during acidification. The s crape and titrate method, involving the separation of epiphyte materia l from the seagrass leaves, is believed to most accurately measure epi phytic carbonate.