Ice mountains 'disrupt' ecological diversity in the Antarctic seabed

Antarctic worms, sea spiders, sea urchins and other marine species that live near the shore are often hit by glaciers. New information shows that the habitat along the Antarctic Peninsula will be even more attacked by icebergs. This is because the number of glaciers moving through the sea floor is increasing from the shrinking sea ice phenomenon.

Scientists from the British Antarctic Survey (BAS) have shown how the length of the winter ice sheet affects the proportion of glaciers that sweep across the western seabed of the Antarctic while the number of glaciers in the region often decreased (in space and time) over the past few decades due to global warming. Glaciers are seriously harassing marine creatures living at a depth of 500m on the seabed, where 80% of the Antarctic's living organisms are concentrated.

A British biology marine biologist sees huge sponges at a water level of 20m from the sea.(Photo: Image courtesy of British Antarctic Survey)

Dr. Dan Smale of BAS said: 'Previously, it was assumed that the degree of ice influence could be controlled by winter ice formation, but no one went out there to verify it. We were surprised to see the close relationship of these two factors. For many years with the ice season that lasted for about 8 months, the effect of the glacier was very low, while for less ice years, the sea floor was harassed almost all year round. It is a bandage fixed by the winter ice in a position, but they are not free to flutter with wind and water until they hit the seabed '.

By using the grid to control small markers on the seabed at 3 different heights for 5 years, BAS divers were able to determine the frequency of glaciers sweeping through the seabed by the counting method. Markers are damaged or damaged annually.

The disturbing ice is now considered the driving force of the Antarctic seabed community structure. Glaciers destroy the sea floor which is home to many species. However, an increase in the occurrence of this phenomenon will affect the type and number of marine life at the seabed, thereby causing changes in the distribution of key species.

Basic information

Ice mountains are large freshwater ice sheets separated from glaciers or ice sheets formed by snow and floating on the water. There are many factors that affect the ability of icebergs to impact on the sea floor. These include depth, seabed topography, distance to ice sources, wind direction and tide.

The Antarctic Peninsula is a rapidly changing climate. Antarctica is also heating up faster than anywhere in the Southern hemisphere over the past half century. Weather records from the west coast of the Antarctic Peninsula show that the regional air temperature has increased by almost 3 degrees Celsius during the past 50 years , several times the global average and only relative to Alaska. The above information is also the final publication of marine biologist Kirsty Brown, who died in a field trip to Antarctica in 2003.

Reference article:
Dan A. Smale, Kirsty M. Brown, David KA Barnes, Keiron PP Fraser and Andrew Clarke.Ice scour disturbance in Antarctic waters.Science, July 18, 2008