GGR227H5 Lecture Notes - Lecture 18: Sphagnum, Salix Herbacea, Betula Nana
Document Summary
The arctic is the region of land and ocean that centers roughly on the north pole and extends southward to and beyond the arctic circle. Climate condition: brief and cool summer; long, dark and icy winter geomorphic provinces. Shields: large, tectonically stable areas of very ancient rocks that have been exposed and leveled by erosion: platforms: bedrock has been buried under deep glacial, alluvial, or marine deposits, mountains: uplifted and distorted sedimentary mountain and volcanic islands. Subzone a: polar desert. coldest, mostly barren and dry, with permanently frozen subsoil. Some sites bear a thin cover of lichens, mosses, bryophytes, low grasses, and a few wildflowers. Wildlife: polar bears, arctic hares, snowy owls: subzone b & c: high arctic tundra. Highly uneven cover of mosses, lichens, dwarf willows, scurvygrass, and wildflowers. Wildlife: muskoxen, arctic foxes, wolves, stoats, caribou, eiders: subzone d & e: low arctic tundra.