ENRICHMENT OF INORGANIC NUTRIENTS: BIOLOGICAL CONSEQUENCES OF GIANT CLAMS (TRIDACNIDAE)

Abstract

Some aspects were considered here: 1) giant clam populations around the world are depleted rapidly; 2) giant clams can be easily cultured, 3) coral reef ecosystems (where clam populations can be found) have low concentration of nutrients. Laboratory experiments showed that increasing nutrient concentration enhanced the clams growth rate, soft tissue weight, zooxanthellae density, chlorophyll a content. These results have raised the suggestion that it is, possibly, important to fertilize the sea bed where the clams being cultured. Field experiments, however, did not observe changes in clams growth, soft tissue weight, and respiration/photosynthetic rates of the clams. These results suggest that enrichment of nutrient in the field not only impracticable and uneconomical, but also does not give any advantages to the clams.