A treeless area between the icecap and the tree line of Arctic regions,having a permanently frozen subsoil and supporting low-growing vegetation such as lichens,mosses,and stunted shrubs.

• 苔原北极地区冰盖和乔本植被线之间的无树地区，有永冻底土，并支撑低的植物，如苔藓、地衣和发育不全的灌木。