| Abstrakt: |
The objective of this paper is to discuss the background in the development of the hydric soil definition and criteria. The hydric soil classification was developed at the request of the Fish and Wildlife Service as a tool for use in the National Wetlands Inventory (NWI) of the USA. The objective of creating a hydric class of soils was to develop a class of soils that correlated with the presence of hydrophytic vegetation. This list of hydric soils in conjunction with soil surveys is used to help identify wetlands in the NWI. Development of the hydric soils classification was a result of extensive field studies and testing of proposed definitions. The resulting definition and criteria for hydric soils uses water table depths, flooding and ponding, drainage class, and permeability properties and qualities from the national soil survey database, and the aquic and Histosol classes in Soil Taxonomy. The definition and criteria were developed to generate a national list of hydric soils that support hydrophytic vegetation. The criteria were not meant for field use in identifying hydric soils. The use of morphologic indicators are suggested for field identification of hydric soils. |
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