INVESTIGADORES
SCHLOSS Irene Ruth
artículos
Título:
Aggregation of algae released from melting sea ice: Implications for seeding and sedimentation.
Autor/es:
RIEBESELL, U., SCHLOSS, I.R. AND SMETACEK, V.
Revista:
POLAR BIOLOGY
Referencias:
Año: 1991 p. 239 - 249
ISSN:
0722-4060
Resumen:
Summary. Factors influencing the fate of ice algae released
from melting sea ice were studied during a R V Polarstern
from melting sea ice were studied during a R V Polarstern
from melting sea ice were studied during a R V Polarstern
Factors influencing the fate of ice algae released
from melting sea ice were studied during a R V Polarsterna R V Polarstern
cruise (EPOS Leg 2) to the northwestern Weddell Sea. The
large-scale phytoplankton distribution patterns across the
receding ice edge and small-scale profiling of the water
column adjacent to melting ice floes indicated marked
patchiness on both scales. The contribution of typical ice
algae to the phytoplankton was not significant. In experiments
simulating the conditions during sea ice melting,
ice algae revealed a strong propensity to form aggregates.
Differences in the aggregation potential were found
for algal assemblages collected from the ice interior and
the infiltration layer. Although all algal species collected
from the ice were also found in aggregates, the species
composition of dispersed and aggregated algae differed
significantly. Aggregates were of a characteristic structure
consisting of monospecific microaggregates which are
likely to have formed in the minute brine pockets and
channels within the ice. Sinking rates of aggregates were
three orders of magnitude higher than those of dispersed
ice algae. These observations, combined with the negligible
seeding effect of ice algae found during this study,
suggest that ice algae released from the melting sea ice are
subject to rapid sedimentation. High grazing pressure at
the ice edge of the investigation area is another factor
eliminating ice algae released during melting.