BIOL361 Lecture 24: Arcitc and Antarcti marine ecosystems
6 May 2017
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Document Summary
The arctic is an ocean surrounded by land. The antarctica is a continent surrounded by ocean: arctic. Low degree of endemism (no endemic genera) Terrestrial predators, much greater diversity of birds and mammals than antarctica. Zones of the high arctic marine ecosystem: boreal littoral, high artic shallow, high arctic brackish, high arctic abyssal. Represents 15-30% of total productivity over the continental shelf, protracted phytoplankton bloom, influenced by snow cover & multiple layer. Winds that alternate between onshore and offshore maintain coastal shore, lead polynya systems along the coastlines of the mainland (hudson bay and high arctic archipelagos). Some species in the arctic don"t have an ecological or behavioral antarctic equivalent: no equivalent benthic feeders in the antarctica. Whales don"t have a dorsal fin so they can break re-freezing ice to breathe and winter in pack ice. Belugas use their backs to make breathing holes in a re-frozen lead in the beaufort sea.
