The new National Vegetation Classification Standard adopted by the FGDC in 2008 replaced the original (1997) Standard and includes a substantially revised hierarchy with a greater emphasis on biogeography and floristics in a new set of middle levels. Here we present examples of how vegetation data are assigned into this new hierarchy. Data were collected from 1503 plots within Grand Canyon National Park (GRCA) and adjacent areas of Grand Canyon Parashant National Monument (PARA) at elevations ranging from 400 to 2700m as part of the GRCA / PARA vegetation classification and mapping project. Plot data were analyzed in three ways: ordination with NMDS, cluster analysis using both divisive and agglomerative methods, and comparison to classified plots in nearby NPS units.
Results/Conclusions
Plots have been assigned to approximately 140 vegetation classes and tentatively placed in the new hierarchy. Vegetation in the plots had affinities to several regions, including Mojavean, Great Basin and Southern Rocky Mountains. We contrast our arrangement to the hierarchy associated with the 1997 Standard and demonstrate where significant improvements have been made.
