Premium
The origin of sedimenting detrital matter in a coastal system
Author(s) -
Lundsgaard Claus,
Olesen Michael
Publication year - 1997
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.1997.42.5.1001
Subject(s) - copepod , pelagic zone , photic zone , detritus , sedimentation , marine snow , heterotroph , pellets , organic matter , oceanography , microbial loop , environmental science , biology , ecology , geology , water column , phytoplankton , crustacean , nutrient , sediment , paleontology , genetics , bacteria
Total sedimentation and the fraction due to copepod fecal pellets were measured during the growth season (March–October 1989) in the southern Kattegat, Denmark. In this period the sedimentation of detritus made up 52 g C m −2 , equal to 82% of the sedimenting matter from the euphotic zone, but fecal pellets (11 g C m −2 ) constituted only a minor fraction. The remaining detrital matter was produced by other heterotrophs than copepods. Published data on heterotrophic biomass and grazing obtained during the investigation in the Kattegat are reviewed in order to relate the sedimentation to processes in the pelagic system. Copepod defecation nearly equaled the sedimentation of fecal pellets, indicating that retention of this matter in the pelagic system was insignificant. A considerable fraction (10–24%) of the carbon flow processed by heterotrophic pico‐, nano‐, and microplankton was converted to detritus that was lost from the mixed system by sedimentation. The microbial food web is thus not an exclusively regenerating system.