Comparison of carbon and nitrogen content in natural and Aulacomya atra (MOLINA) biodeposits.

Abstract

Biodeposition “in situ” of Aulacomya atra (Molina), the subantarctic ribbed mussel, is studied by collector cylinder system. In order to evalúate the contribution of this species to the oiganic carbón and nitrogen flux in Puerto Madryn bay ecosystem, the organic carbón and organic nitrogen contents in biodeposits were measured and compared with those from natural biodeposits of the area. Mean annual valúes were 3.03 g C. nr2. day1 and 0.23 g N. nr2 day1 in mussel biodeposits and 3.16 g C. nr2. day1 and 0.25 g N. nr2. day1 in natural biodeposits. The mean annual concentration were 9.24 g C and 0.58 g N in lOOg of mussel biodeposists and 6.68 g C and 0.44g N in lOOg of natural biodeposits. From Friedman’s test results tlie carbon and nitrogen contents and concentrations were similar both in mussel and natural biodeposists. The C/N ratio for mussel biodeposits was smaller than that of natural biodeposits only in summer months.