The major goal of this investigation is to determine the interactive effects of oxygen from overlaying water, microbially produced sulfide and sedimentary organic carbon on food sources, growth, and metabolic pathways in marine invertebrates living in the benthos. The investigators will determine the factors controlling acquisition of oxygen and organic carbon, and then test the hypotheses that (1) growth is controlled more by the interactions between oxygen, sulfide and organic carbon rather than any one factor, (2) that sulfide is not required for growth, that Heteromastus will absorb more organic matter from deep sediment than from surface sediment, and that (3) tail-nipping increases ventilation. We will also determine whether symbiotic sulfide oxidation occurs in a deposit feeding polychaete. Preliminary investigations will be made on the effects of oxygen and sulfide on metabolic heat production and state of the heme protein, cytochromes and hemoglobin.
