tundramargin

Tundramargin, sometimes called the tundra margin, is an ecological term describing the ecotone at the edge of tundra ecosystems where tundra grades into adjacent biomes such as boreal forests to the south or alpine zones at high elevations, and in some coastal regions into polar deserts. The term emphasizes transitional environments rather than core tundra habitat, highlighting gradual changes in climate, soils, and biotic communities across the boundary.

Physical conditions at the tundramargin are variable but typically show shorter growing seasons, cooler temperatures than temperate zones, and soils with shallow active layers over permafrost or seasonally thawed layers depending on moisture and drainage. Topography creates microhabitats that further diversify plant communities.

Flora and fauna in tundramargins include plant communities with dwarf shrubs (for example Betula nana and Salix species), mosses, lichens, and hardy grasses; tree establishment is limited by cold summers and permafrost in many Arctic margins. Animal communities vary by location and can include Arctic hares, lemmings, caribou, and other herbivores and predators adapted to extreme conditions.

Geographic distribution occurs along Arctic coasts and continental margins in Eurasia and North America and on high mountain belts worldwide. In flat terrain it presents as a band between continuous tundra and boreal forest, while in mountains it often appears as alpine tundra margins at varying elevations.

Ecological significance and climate change: tundramargins are dynamic interfaces that respond to warming with shrubification and southward or upslope treeline advance, altering albedo, hydrology, and carbon storage. They are monitored as indicators of regional climate change and are studied with field plots and remote sensing.