Decomposition processes and trace metals in muds of the Gulf of Papua, Papua New Guinea

Nutrient chemistry and rates of nutrient regeneration were examined in muds of the Gulf of Paupa, Papua New Guinea. Samples were taken from 3 new sites (IGP1, IGP2, IGP3) and 2 sites previously sampled in 1990 (D9, GP8).Sedimentary variables were: temperature; grain size; salinity; porosity; and percent sand, silt and clay.Dissolved solute (DON, DOP, ammonium, nitrite, nitrate, phosphate, silicate, DOC, Fe, Mn) flux measurements and primary production (O2 flux) were made for each site.Cores were taken for measurements of solid-phase elements (TOC, TN, TP, TS) and porewater nutrients at each site.The concentrations of solid-phase and dissolved trace metals (Al, Fe, Mn, Mo, Ni, Cu, Co), including sediment-water interface, were measured. To describe rates of bacterial composition and recycling of organic matter in the upper sediment layers (0-20 cm) of these inner shelf muds and their contribution to primary pelagic production.To assess the role of post-oxic muds in the flux of trace metals into the Coral Sea. This research project was a component of a larger project to determine the influence of freshwater and detrital export from the Fly River system on adjacent pelagic and benthic systems.