Competition causes regular spacing of alder in Alaskan shrub tundra.

摘要: Alders (Alnus crispa) in shrub tundra northern Alaska showed significant regularity of spacing. Removal neighboring alder shrubs stimulated nutrient accumulation and growth remaining alders but did not stimulate or any other species. This demonstrates that competed with one another that, when were removed, the resources made available used preferentially by rather than community general. Neither patterns seedling establishment nor frostrelated features could explain regular distribution alder. We suggest plant are restricted to sites low-resource availability, because these habitats (1) there is strong competition for a scarce resource, (2) only few dominant species compete given canopy height rooting depth.