Faecal pellet production by Arctic under-ice amphipods: transfer of organic matter through the ice/water interface
Werner, I. (2000). Faecal pellet production by Arctic under-ice amphipods: transfer of organic matter through the ice/water interface, in: Liebezeit, G. et al. Life at Interfaces and Under Extreme Conditions: Proceedings of the 33rd European Marine Biology Symposium, Wilhelmshaven, Germany, 7-11 September 1998. Developments in Hydrobiology, 151: pp. 89-96. https://dx.doi.org/10.1007/978-94-011-4148-2_8 In: Liebezeit, G.; Dittmann, S.; Kröncke, I. (Ed.) (2000). Life at interfaces and under extreme conditions: Proceedings of the 33rd European Marine Biology Symposium, Wilhelmshaven, Germany, 7-11 September 1998. European Marine Biology Symposia, 33. Developments in Hydrobiology, 151. ISBN 978-0-7923-6468-9; e-ISBN 978-94-011-4148-2. VII, 210 pp. https://dx.doi.org/10.1007/978-94-011-4148-2, more In: European Marine Biology Symposia., more |
| Keywords | Excretory products > Faecal pellets
Interfaces > Ice-water interface
Amphipoda [WoRMS]; Apherusa glacialis (Hansen, 1888) [WoRMS]; Gammarus wilkitzkii Birula, 1897 [WoRMS]; Onisimus Boeck, 1871 [WoRMS]
PN, Arctic [Marine Regions]
Marine/Coastal |
| Abstract | The underside of Arctic sea ice is inhabited by several autochthonous amphipod species (Apherusa glacialis, Onisimus spp., Gammarus wilkitzkii). The amphipods graze on ice-bound organic matter, such as ice algae, detritus and ice fauna, and release faecal pellets into the underlying water column, thus forming a direct link between the sea ice and the pelagic ecosystems. Experiments on faecal pellet production rates showed species-specific differences, which were related to size of the animals. The smallest species, A. glacialis, produced the highest mean number of pellets (15.4 pellets ind.-1 d-1), followed by Onisimus spp. (2.7 pellets ind.-1 d-1) and the largest species, G. wilkitzkii (1.1 pellets ind.-1 d-1). Relative carbon content of the pellets was very similar in all species (21.2-22.6% dry mass). Juvenile amphipods (Onisimus spp., G. wilkitzkii) produced more pellets with less POC than adults. Based on field determinations of the POC concentration in the lowermost 2 cm of the sea ice (mean: 36.4 mg C m-2) and mean amphipod abundances (A. glacialis: 33.8 ind. m-2, Onisimus spp.: 0.5 ind. m-2, G, wilkitzkii: 9.4 ind. m-2) in the Greenland Sea in summer 1994, the amount of POC transferred from the ice to the water by faecal pellet production was estimated (0.7 mg C m-2 d-1 or almost 2% of ice-bound carbon). Since this process probably takes place in all ice-covered Arctic regions as well as during all seasons, grazing and pellet production by under-ice amphipods contributes significantly to matter flux across the ice/water interface. |
|
