9633586 Berelson In order to understand the chemistry of the ocean one must somehow measure the rates that substances enter and leave the ocean at its boundaries. In this study the principal investigator will design, construct, and test a "test-series lander" (TSL) - a device that directly measures the flux of dissolved substances across the sediment-water interface by taking a series of overlying water samples in sequence. The TSL will use each of its eight 'spider arms' to implace an upside-down chamber on the sediment surface at preset times. By sampling the seawater inside the chambers over time (up to five programmable times, spaced over sampling periods of minutes to months) one can collect data to calculate the flux of solutes of interest across the sediment-water interface. An important time-and money-saving feature of the TSL to be developed in this study is its ability to operate as an unattended 'free vehicle' that can be programmed, deployed from shipboard, and retrieved weeks or months later.
