Distribution and sedimentation of faecal on the Nordvestbanken shelf, northern Norway, in 1994

Abstract

Abstract A close seasonal coherence between mesozooplankton and abundance of faecal pellets was encountered at Nordvestbanken, northern Norwegian shelf, in 1994. Mesozooplankton at Nordvestbanken influenced the vertical flux of organic matter by production, consumption, modification, and destruction of faecal pellets. On average, 11-37% of particulate organic, vertical carbon flux was comprised by faecal pellets. The pelagic degradation of organic matter at Nordvestbanken appears to be reduced due to the low pelagic residence time in the upper 100 m of the water column of faecal pellets ( 1.3-8.3 d). The specific seasonal sinking rates of faecal pellets (12-77 m d-1)fell well into the range of in situ and in vitro sinking rates reported in the literature for the dominating classes of faecal pellets al Nordvestbanken, i.e. from calanoid copepods and pteropods. The shape, colour, density, and degree of fragmentation of faecal pellets appears to reflect variations and changir1g preferences in the diet of mes...