Mk. Zdanowski et Sp. Donachie, BACTERIA IN THE SEA-ICE ZONE BETWEEN ELEPHANT-ISLAND AND THE SOUTH-ORKNEYS DURING THE POLISH SEA-ICE ZONE EXPEDITION, (DECEMBER 1988 TO JANUARY 1989), Polar biology, 13(4), 1993, pp. 245-254
During austral summer 1988/89, total bacterial Acridine Orange Direct
Counts (AODC) in seawater, mean 6.0 x 1O(6) l-1, were three to ten tim
es lower than generally reported for the Bransfield Strait to north We
ddell Sea area. In contrast, numbers of viable bacteria (Colony Formin
g Units, CFU), mean 10.6 x 10(3) l-1, were two to three times higher t
han reported. Bacterial abundance here shows large seasonal and spatia
l changes. On the basis of bacterial, diatom, detritus, and amino acid
data from this study, two main regions were defined: 'Cold winter wat
er' in the west with high salinity and low CFU, AODC, and other parame
ters. In the east, lower salinity and higher values for all parameters
were found in warmer meltwater at the surface. CFU and AODC values in
ice were respectively six and 85 times higher than in surrounding sea
water. Taxonomic studies indicate considerable diversity in genera and
nutritional requirements of isolated bacteria. Sea-ice and water colu
mn bacterial communities differed. Many isolated strains, however, wer
e found in both habitats. Sea-ice seems to be important in regulating
surrounding bacterioplankton.