| активный слой | active layer (In environments containing permafrost, the active layer is the top layer of soil that thaws during the summer and freezes again during the autumn.: Permafrost is soil, rock or sediment that is frozen for more than two consecutive years. In areas not overlain by ice, it exists beneath a layer of soil, rock or sediment, which freezes and thaws annually and is called the "active layer"  wikipedia.org) |
