Four cruises were carried out on the R/V Beidou during 14-28 April 2006, 17 October-3 November 2006, 17-23 March 2007 and 3-9 August 2007. At each station, hydrographic measurements and water samples were conducted using a Seabird SBE 19 CTD profiler equipped with a 12 Niskin bottle Rosette samplers. Two stations (B2,B3) were not sampled during the April cruise, one station (H2) during the October cruise, and Transect Y (Station Y2-8) during the August cruise.