Vegetation Communities in Relation to Environmental Gradients in Shenandoah National Park

Executive Summary This report documents the results of a 4 year research project to assess and map vegetation communities of Shenandoah National Park. The project was a collaborative effort between Shenandoah National Park, the US Geological Survey-Leetown Science Center, the Virginia Department of Conservation and Recreation-Division of Natural Heritage, the University of Maryland Center for Environmental Science-Appalachian Laboratory, and The Nature Conservancy. While set up as a research project rather than strictly a mapping effort, the result of the project is a new map of vegetation distribution in Shenandoah National Park based on U.S. National Vegetation Classification System standards. Additional products include a classification scheme of vegetation communities in the Park based on field sampling of 311 vegetation plots, maps of landforms, ecological land units, and environmental gradients, and an assessment of the relationship between vegetation community distribution and environmental gradients. Additionally we tested the capability of mapping vegetation communities using hyperspectral remote sensing, environmental gradient maps, and statistical modeling. We classified 34 vegetation communities at the association-level of the National Vegetation Classification System within Shenandoah National Park. Three community types were newly classified and described. We mapped vegetation communities to the association level using AVIRIS spring 2000 and summer 2001 hyperspectral imagery, and we filled in missing areas with Landsat TM multispectral imagery. We validated the results using internal cross validation and through an accuracy assessment campaign conducted at 224 field plots in the summer of 2004,. Results of accuracy assessment range from 89% overall accuracy from internal validation to 67% accuracy from field validation. Additional field validation was conducted as an addendum to this project (summer of 2005) to increase the sample size and reliability of the initial accuracy assessment campaign, and to guide any necessary modifications to the vegetation maps. Final Products: (Final Report, GIS data, print maps, etc.) Links: Shenandoah National Park USGS/NPS Vegetation Mapping Program Virginia Natural Heritage Program website Natural Communities of Virginia, 2nd approximation Ecological Communities of the Northern Blue Ridge (Powerpoint PDF) National Vegetation Classification - NatureServe For more information, contact John Young (jyoung@usgs.gov).