This project is a study of the rate of production and dissolution of biogenic silica in the uppermost 150 meters of the Ross Sea, and is part of a coordinated study of the biogenic silica and organic carbon cycling in the water column and the sediments of the Ross Sea. The antarctic deep sea and continental shelf environment is the major repository for silica accumulation in the global ocean, and dominates the global silica budget, The Ross Sea is a particularly anomalous area in which large amounts of biogenic silica are accumulating in modern sediments, while the surface production rates are generally below the global average. Moreover the usual similarity between the oceanic silicon and carbon cycle does not appear to hold around Antarctica, and the two cycles are decoupled in that the rate of particulate carbon deposition in the modern sediment is very low. The project is an integrated study of the production, vertical transport, dissolution, and deposition processes, using moored instrumentation and direct observations in a series of transects in the Ross Sea by R/V POLAR DUKE. The objectives of the project are to measure the seasonal variability of silica production and dissolution rates in areas of silica-rich and silica-poor surface sediments, and to produce the surface silica budget that will be combined with vertical flux and sediment accumulation data to be obtained by the cooperating investigators.//
