Preferred Term:
permafrost
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.
Concept Schemes:
NALT Full
NALT Core
NALT Core
Broader Concept:
Entry Terms:
- permafrost areas
URI:
https://lod.nal.usda.gov/nalt/27783
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RDF/XMLCreated 2006-01-19, last modified 2017-06-02