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NALT Full

Preferred term

permafrost

Type

Topic

Definition

Permanently frozen ground; generally refers to a layer at some depth below the soil surface. Any layer above it, which thaws in summer, is termed the active layer.
Source: Burns, Russell M. and Barbara H. Honkala, tech. coords. Silvics of North America, vol 2. Hardwoods; Glossary. Agriculture handbook no. 654. U.S. Department of Agriculture, Forest Service, 1990
Type: Concept definition

Broader concept

soil morphological features

Related concepts

Synonyms

permafrost areas

In other languages

hielo permanente

Spanish

URI

https://lod.nal.usda.gov/nalt/27783

Download this concept:

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