Pressure Studies on Unicellular Algae, Marine Invertebrates and Biogenic Carbonates

摘要

An open-system high pressure aquarium is described. Data are presented on experiments performed with this equipment on marine vagrant benthic invertebrates derived from the surface waters and dredged from depths between 46 and 64 meters and 560 and 730 meters. The suitability of the equipment for long-range pressure studies is demonstrated by maintaining experimental animals at elevated pressures for periods up to 6 months. Dissolution experiments were performed from undersaturation in H2CO3 solutions at pressures ranging from atmospheric to 10,000 psi, with in situ pH measurements and ambient analytical cation determinations. The increase in solubility of calcite with pressure is due approximately half to the increased dissociation of H2CO3 with increased pressure and half to the increased solubility of the solid. Both aragonite and Mg-calcites appear to become increasingly more soluble than calcite with increasing pressure. Data are also presented of the effects of increased hydrostatic pressure on the growth rates of 10 species of unicellular algae in a closed system. A Schlieren technique was developed to study the flow pattern produced by filter feeders to assess their suitability and required water flow rates in our pressure equipment. (Author)