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CAVICE
Cave ice microbiom: metabolic diversity and
activity in response to climate dynamics and anthropogenic pollution
Diversitatea şi activitatea metabolicǎ a microbiomului
peşterilor de gheaţǎ ca rǎspuns la schimbǎrile climatice şi poluarea
antropicǎ
Project Coordinator: Dr. CRISTINA PURCAREA
ELAC2014/DCC-0178
Scarisoara Ice Cave (SC) (700
m long, 105 m deep), located in the Apuseni Mountains Natural Park, Romania,
contains one of the oldest and largest subterranean ice block in the world,
radiocarbon dated to be more than 1,000 years old. This cave’s ice block,
with a volume of 100,000 m3 and areal extent of 3,000 m2,
constitutes a chronological record of changes in climate and biodiversity
embedded in annuallyaccumulated ice layers. The peculiar morphology of the
cave, with entrances located in the upper part only, leads to cold air
influx during winter months, inducing freezing of the water inside the cave,
with accumulation of ice layers that generate the large deposit of perennial
ice. The ice deposit consists of a sequence of annually laminated layers
containing clear ice and sediment strata (organic matter, calcite, soil, and
pollen), visible on the lateral, ablation walls of the block. In summer, the
high dripping rates bring large quantities of warm water (56 ºC) into the
cave that determine the partial melting (up to a few cm) of ice. 14C-dating
and paleoclimate investigations were extensively carried out on SC ice
block. Recent studies, making the object of a funded research of the
Romanian PI’s group (C. Purcarea), started the investigation of microbial
diversity and distribution in the ice deposits of this cave, revealing the
existence of prokaryotic and eukaryotic microbial communities in ice up to
900 years old.
Svarthamar Ice Cave (SV) is
the largest natural cave room in Scandinavia and one of the lowest altitude
ice caves in Europe. It is situated 275 m a.s.l. (ca N 67°12’; E1° 30’)
close to Bodø, Norway. The cave has two main entrances at a Δh of 40 m,
sufficient to drive thermal winds and support a perennial ice mass of some 4
000 m3, with a stratigraphic thickness of 520 m. Radiocarbon dating of
plant debris at the base of the ice indicates that ice accumulation
commenced after AD 1200. The cave was surveyed and an instrumental
monitoring program initiated in 2004. Our results demonstrate that the ice
mass is rapidly ablating most probably as a result of global warming. The
main accumulation period of ice occurs during spring snowmelt, when surface
melt water enters a deeply undercooled cave. In contrast to SC ice cave, SV
is a dynamic cave due to the two entrances at different levels, showing an
accelerating ablation rate during summer and fall for the last 30 years.
Moreover, presence of uncontrolled tourism, make this cave a study case for
the anthropogenic impact on this type of ecosystem.
Viedma Glacier Cave (VD) The
Viedma Glacier is the largest glacier in Argentina, located on the Northern
area of Los Glaciares National Park, province of Santa Cruz, in the Southern
Andes (49°31’S, 73°01’W). This glacier arises in the Southeast of Lautaro
Volcano and it has a length of 70 Km and has an area of approximately 900
Km2. It is also known for the three bands of ashes product of past eruptions
of the volcano. The Viedma Glacier flows directly from the South Patagonic
Ice Field to the Viedma Lake, which is mainly fed by its melting ice. Its
front rises about 130 ft above the level of the Lake. Its origin can be
located in the very heart of the Ice Field between 5,000 and 7,000 ft above
sea level. The Viedma Glacier Cave is one of the main tourist attractions,
but there is no information about the anthropogenic impact on their
microbiom diversity and activity. For many years, the increasing mean annual
temperatures determined a general recession of most of the Patagonia
glaciers, mainly due to loss of accumulation area, rising temperatures at
the glacier snout elevation, and increase of ice calving in lakes or the
sea. A maximum recession of around 2.5 km was observed between 1944-1984
and the glacier surface lowered from 40 to 120 m, modifying the pristine
environments, water resources, alpine wetlands, scenic and tourism
resources. In this respect, Viedma Glacier Cave represents a good model for
studying the composition of total and active microbiom characteristic for
this glacier, as a representative unexposed ecosystem.
Grey Glacier Cave
(GR).
Grey Glacier
is located in Patagonia, Chile, belonging to the Southern
Patagonian Ice Field,
Chile,
which is the world’s second largest contiguous ice field outside the poles
(16,800 square km ice mass including dozens of glaciers). GR is
located on the west side of the Torres
del Paine National Park
and is one of the smallest (270 square km) in the area. Glacier caves
forming temporarily in the ice mass of GR represent good models for studying
the impact of anthropogenic and environmental pollution on the microcosm
from Chilean glacial habitats.
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