INVESTIGADORES
RUBERTO Lucas Adolfo Mauro
artículos
Título:
The water column as an attenuating factor of the UVR effects on bacteria from a coastal Antarctic marine environment
Autor/es:
HERNÁNDEZ E; FERREYRA G; RUBERTO L; MAC CORMACK W.P
Revista:
POLAR RESEARCH
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2009 p. 390 - 398
ISSN:
0800-0395
Resumen:
The effect of UVR on the viability of the culturable bacterial community
fraction (CBC), and two of their isolated components (Arthrobacter-UVvi andArthrobacter-UVvi and
Bizionia-UVps), was studied in the top few metres of the water column at Potter
Cove, King George Island, Antarctica. Quartz flasks containing CBC from
surface waters were exposed to solar radiation at depths of 0, 1 and 3 m.
Similar experiments using UVps and UVvi isolates were performed. In some
experiments interferential filters were used to discriminate photosynthetic
active radiation (PAR), UV-A and UV-B. CBC from depths of 0, 10 and 30 m
were also exposed to surface solar radiation. The deleterious effect of UVR was
observed at the surface and at a depth of 1 m, but not at a depth of 3 m. Studies
with interferential filters showed low bacterial viability values at depths of 0
and 1 m under both UVR treatments. However, under low radiation doses the
effect attributed to UV-B was higher than that caused by UV-A. The surface
CBC was more resistant to UVR compared with CBC from a depth of 30 m. The
results showed that CBC inhabiting waters above the pycnocline (located at a
depth of 510 m) are more efficiently adapted to UVR than are those from
below the pycnocline. The impact of UVR on the marine bacterioplankton
studied was only detected in the first metre of the stratified water column of
Potter Cove, which has high levels of suspended particulate matter. These
results support the evidence for a significant UVR-attenuating effect in the
water column of this coastal Antarctic water.-UVps), was studied in the top few metres of the water column at Potter
Cove, King George Island, Antarctica. Quartz flasks containing CBC from
surface waters were exposed to solar radiation at depths of 0, 1 and 3 m.
Similar experiments using UVps and UVvi isolates were performed. In some
experiments interferential filters were used to discriminate photosynthetic
active radiation (PAR), UV-A and UV-B. CBC from depths of 0, 10 and 30 m
were also exposed to surface solar radiation. The deleterious effect of UVR was
observed at the surface and at a depth of 1 m, but not at a depth of 3 m. Studies
with interferential filters showed low bacterial viability values at depths of 0
and 1 m under both UVR treatments. However, under low radiation doses the
effect attributed to UV-B was higher than that caused by UV-A. The surface
CBC was more resistant to UVR compared with CBC from a depth of 30 m. The
results showed that CBC inhabiting waters above the pycnocline (located at a
depth of 510 m) are more efficiently adapted to UVR than are those from
below the pycnocline. The impact of UVR on the marine bacterioplankton
studied was only detected in the first metre of the stratified water column of
Potter Cove, which has high levels of suspended particulate matter. These
results support the evidence for a significant UVR-attenuating effect in the
water column of this coastal Antarctic water.