146
Land-Ocean Systems in the Siberian Arctic: Dynamics and Histor:y
East Siberian Sea
o
Laptev
Sea
Khatanga
Taymyr
Peninsula
= 1 ~g cm- 3
Figure 2: Distribution of chlorophyll a equivalents (chlorophyll a and phaeopigments) in the Laptev Sea.
Columns represent values in the surface sediments (0-1 em). ARK IXl4. ARK XIII.
parameters was as high as r=0.70 for all samples (n=58).
Only 10-20 % of the organic matter produced in the euphotic zone is exported since most of it
is remineralized (Martin et aI., 1987). During sinking the particles are further degraded due to
zooplankton grazing, bacterial lysis and chemical processes (Karl et aI., 1988). Therefore,
particulate organic matter flux to the sediment decreases exponentially in quantity and
additionally in quality with increasing water depth (Honjo et aI., 1988; Suess, 1980). These
processes could be responsible for the large reduction in pigment concentrations and microbial
activity in the Arctic slope sediments, and Wheeler et al. (1996) found that heterotrophic
degradation processes in the Arctic water column function as efficiently as in other oceanic
Land-Ocean Systems in the Siberian Arctic: Dynamics and Histor:y
East Siberian Sea
o
Laptev
Sea
Khatanga
Taymyr
Peninsula
= 1 ~g cm- 3
Figure 2: Distribution of chlorophyll a equivalents (chlorophyll a and phaeopigments) in the Laptev Sea.
Columns represent values in the surface sediments (0-1 em). ARK IXl4. ARK XIII.
parameters was as high as r=0.70 for all samples (n=58).
Only 10-20 % of the organic matter produced in the euphotic zone is exported since most of it
is remineralized (Martin et aI., 1987). During sinking the particles are further degraded due to
zooplankton grazing, bacterial lysis and chemical processes (Karl et aI., 1988). Therefore,
particulate organic matter flux to the sediment decreases exponentially in quantity and
additionally in quality with increasing water depth (Honjo et aI., 1988; Suess, 1980). These
processes could be responsible for the large reduction in pigment concentrations and microbial
activity in the Arctic slope sediments, and Wheeler et al. (1996) found that heterotrophic
degradation processes in the Arctic water column function as efficiently as in other oceanic