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Plants and Vegetation
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Vegetation and soils in high latitudes 
  • American, Canadian and Russian ecologists define arctic and subarctic zones in contrasting ways. 
  • The soil catena is the fundamental unit of study in polar regions, as it encompasses local variations in topography, permafrost depth, hydrology, soils and plant communities. 
  • Arctic Brown soils occur on well drained sites, Tundra Gleys on poorly drained sites, and Peaty Tundra Gleys on very poorly drained sites in the Low Arctic. 
  • Polar Desert soils, Lithosols and Regosols dominate the High Arctic. 
  • The nutrient content of polar soils is very low, and undoubtedly restricts the productivity of polar ecosystems. 
Plant adaptations in polar regions 
  • Low temperatures are but one of the factors of environmental stress to overcome which polar plants species have had to evolve adaptations. 
  • Low soil nutrient contents, windiness, waterlogging and unweathered regoliths are additional limits on vegetation survival and growth. 
  • Polar plants show a great variety of adaptations to cold by growth, habitat, ecophysiological characteristics and biochemical metabolism. 
  • Waterlogging of the ‘active layer’ of soils means that many polar plants show hydrophytic characteristics. 
  • Areas where snow lingers in early summer usually show a distinctive ‘snow loving’ vegetation. 
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