Identifying aquatic ecosystems requires a classification of stream and lake features into recognizable categories. Although a number of nationally recognized terrestrial community classifications exist, currently there is no national or international standard for classifying aquatic communities or ecosystems. Despite the lack of a national aquatic community classification, aquatic ecosystem classifications and frameworks have been developed at a variety of spatial scales to reflect the distribution of aquatic biological communities. This report reviews these freshwater classification frameworks, providing detailed analysis and application examples of taxonomic, environmental, and hydrologic classifications in use within the Appalachian region.
