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Thesaurus Search Results

permafrost
Subject Category
P Natural Resources, Earth and Environmental Sciences
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.
Definition 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
RDF/XML Format:
http://lod.nal.usda.gov/nalt/27783.rdf
Persistent URI:
http://lod.nal.usda.gov/nalt/27783
Used For
permafrost areas
Broader Term
soil morphological features
Related Term
cold soils
frigid soils
frozen soils
Spanish
hielo permanente
Term Number
27783