Assessment of vegetation plot data availability needed for implementation of the FGDC Standard for revisions to the US National Vegetation Classification

Background/Question/Methods

New US Federal Geographic Data Committee (FGDC) standards, in part developed and now implemented by ESA, mandate that new and revised National Vegetation Classification (NVC) vegetation types be based on high-quality vegetation plot data, as opposed to expert opinion.  VegBank, the US national vegetation plot archive, is maintained by ESA and aims to make plot data available for documentation and revision of the NVC.  We investigated the feasibility of obtaining sufficient data from VegBank and other regional sources to support documentation and revision of the NVC.  The West Virginia Natural Heritage Program database, the Virginia Natural Heritage Program database, and the Carolina Vegetation Survey were used as sources for data for the 4-state region of the Virginias and Carolinas.  The Southeast provided an excellent opportunity for exploring data possibilities as these high-quality databases exist, and the region is diverse in vegetation types, with the NVC currently recognizing 890 associations across the 4-state region, ranging from 225 to 487 per state.  As a whole, the Southeast, Southwest, and Northwest each contain around 2,000 community types, whereas the Northeast and Midwest are less diverse with roughly 600-800 types each.

Results/Conclusions

We obtained 2,692 plots from VegBank from the Virginias and Carolinas, 77% of which were classified as representing one of 364 NVC types (41% of known types).  214 (24%) had at least 5 plots, the mandated  minimum for  revisions.  For the same region, we compiled 15,627 additional plots from regional databases, 89% of which were classified to 763 NVC types (86% of known types).  532 NVC types (60%) were represented by at least 5 plots.  By adding plot resources we doubled VegBank’s plot coverage of NVC types in the four-state area and tripled coverage of minimally attributed. After our efforts, the 14-state Southeast had nearly 20,000 VegBank plots representing 34% of the known types.  In order to meet the new FGDC standards, more plots need to be publicly available. Our initiative was able to greatly increase plot availability for the Southeast, but many more plots will be needed to fully document the NVC and meet FGDC standards. The federal agencies that maintain and implement the FGDC Vegetation Standard need to find mechanisms to make more existing plots available and to acquire new plots needed to comply with the Standard.