| Summary: | The southeastern Bering Sea shelf is an economically and ecologically important system that is subject to substantial natural and human-induced change (National Research Council, 1996). Despite this, long term observations are limited and fragmentary in time and space, which severely restricts our ability to identify the effects of climatic variability on the ecosystem. The only long-term, comprehensive record of the changes in the ocean environment are observations collected from biophysical moorings (Stabeno et aI., 1998; 1999; 2001). Since 1995 Stabeno and collaborators have been monitoring site M2, over the Bering Sea middle shelf near 56 ° N, measuring temperature, salinity, chlorophyll, current speed, and meteorological conditions. A time-series sediment trap, which collects particles sinking out of the surface waters, has been deployed near that mooring since 1997, with support from NOAA during 1997-2000 and with support from the Pollock Conservation Cooperative Research Center for 2001. A parallel time series of zooplankton samples has also been collected. The carbon and nitrogen stable isotope composition and selected lipids, including wax esters and sterols, have been measured in the sediment trap and zooplankton samples. The composition of sinking organic material collected by the trap has reflected changes in oceanographic conditions during the 1997-2001 period.
|
|---|