Pelagic microbial activity in the Northeast Water polynya, summer 1992 |
| |
Authors: | Will Ritzrau |
| |
Institution: | (1) University of Kiel, SFB 313, Heinrich-Hecht-Platz 10, D-24118 Kiel, Germany fax: 011-49-431-880-1569; e-mail: will@sfb313.uni-kiel.de, DE |
| |
Abstract: | Heterotrophic activity and related measures of pelagic microorganisms in the Northeast Water (NEW) polynya, the largest and
northernmost summer polynya in the Arctic, were studied during the Polar Sea cruise of July/August 1992 at stations spanning
a range of ice conditions. Utilization (incorporation and respiration) of 14C-labelled amino acids was measured at in situ temperature as a proxy for microheterotrophic activity in samples from the
chlorophyll maxima, intermediate water depths, and the benthic boundary layer. Total activity and bacterial abundance (measured
by epifluorescence microscopy) were highest in the sub-zero surface water layer that dominates the northeast Greenland shelf,
and particularly in areas most influenced by ice-edge processes and lateral advection. In this cold-water layer activity correlated
strongly with particulate organic carbon (POC), to a lesser degree with phytoplankton-derived pigments and bacterial abundance,
but not with median bacterial cell size. No significant correlations were detected in the warmer, Atlantic-influenced deep
waters of the regional trough system where POC concentrations and other parameters were low. In comparison with temperate
environments, pelagic heterotrophic activity in the NEW polynya appears to be low, a finding that bears upon the fate of dissolved
organic matter and the efficient supply of particulate food to the benthos in this unique polar setting.
Received: 3 December 1995/Accepted:29 May 1996 |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|