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In physical geography, tundra (/ ˈ t ʌ n d r ə, ˈ t ʊ n-/) is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: Arctic, [2] Alpine, [2] and Antarctic. [3] Tundra vegetation is composed of dwarf shrubs, sedges, grasses, mosses, and lichens ...
The arctic tundra has an exceptionally short growing period, minimal sunlight, and limited resources, creating a brutal environment for plants and animals. By adapting to these harsh conditions, animals and plants represent iconic characteristics of the tundra.
Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alpine tundra gets lower until it reaches sea level, and alpine tundra merges with polar tundra .
Once-brown regions are turning green with vegetation, while green areas are turning brown and barren. ... This shift is partly due to giant polar wildfires burning down tundra vegetation and all ...
This area supports wetland plants especially sedges and grasses, mosses and lichens, and right on the coast there are peat bogs. Trees such as dwarf birch , willows , northern Labrador tea ( Dryas ) and alders grow in the warmer areas of the region, the Mackenzie River delta and the Yukon coast.
Arctic vegetation is largely controlled by the mean temperature in July, the warmest month. Arctic vegetation occurs in the tundra climate, where trees cannot grow.Tundra climate has two boundaries: the snow line, where permanent year-round snow and ice are on the ground, and the tree line, where the climate becomes warm enough for trees to grow. [7]
The southern edge of the Canadian Arctic tundra is met by an arboreal tree line - the Arctic forest tundra transition zone. In order to adapt to the extreme conditions of the Arctic, plants have: reduced leaf size to minimize water loss to wind; fuzzy hair-like structures or alternatively grow in mats to protect themselves from snow and wind damage
Tundra ecosystems developed in the Northern Hemisphere toward the end of the Pliocene (3.6 ma), prior to this point the Arctic was predominantly covered with forests and shrublands which extended northward to the coastline of the Arctic Ocean. However, during the middle Pleistocene this vegetation pattern shifted to a graminoid tundra steppe. [18]