| Sediment trap experiments were conducted to assess the production, disintegration and downward flux of zooplankton fecal pellets in the upper 500 m water column of the anticyclonic gyre off Shikoku, Japan. The particulate organic carbon (POC) flux decreased from 53.7 mgC M-2 d-1 at 50 m to 23.7 MgC M-2 d-1 at 500 m. The POC flux at the bottom of the euphotic layer (100 m) was 37.9 mgC m-2 d-1, which was equivalent to about 5 % of the daily primary production in the gyre. The estimated pellet carbon flux accounted for 0.4-1.7 % of the total POC flux. The pellet flux rapidly decreased in the upper 150 m layer, in parallel with the decrease in zooplankton abundance. A mid-depth peak of pellet flux, not associated with a noticeable population of zooplankton,... |
