Identification and Characterization of Disturbed Alder Sites on Elmendorf Air Force Base, Alaska
Abstract
Vegetation data were collected to identify and characterize disturbed alder (Alnus spp.) areas and provide an ArcView GIS layer for specific sites of alder encroachment likely due to human disturbance. Fifty-six plots were established and characterized from sites within previously mapped and delineated polygons on the EAFB vegetation map. Vegetation and physical site characteristics were described at each sample point. Physical site characteristics (e.g., moisture) were summarized and natural vs human-induced successional changes at each alder site were described. All sample plot locations and moisture and disturbance regimes were entered to an ArcView GIS. Alder plot data were investigated to ascertain a means of differentiating disturbed vs undisturbed alder sites in the field using floristic criteria. A multivariate data analysis program (SYN-TAX) was applied using ordination, k-means clustering and range of rows clustering. A stepwise procedure of successive approximations within SYN-TAX was used to further analyze or refine groupings of plots and species representative as they related to disturbed and undisturbed alder sites. The analysis suggested an inability to identify 'disturbed' vs 'undisturbed' alder sites based on their floristic composition. A more qualitative assessment of field work was presented, offering observations to assist Base land managers in their alder management decisions. An ArcView GIS Project was created containing the following theme layers: 1999 edited vegetation map of EAFB; alder plot locations; alder base map; wet alder; alder likely caused by human disturbance; and alder not likely caused by human disturbance. Metadata layers were provided for each of the latter five themes. The design of the GIS layers provides for a variety of queries to be made from each theme as well as using the themes in combination to assess site comparisons. These could prove useful for future separation of plots for management purposes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2001
- Accession Number
- ADA390299
Entities
People
- Gerald F. Tande
- Julie Michaelson
- Susan C. Klein
Organizations
- University of Alaska Anchorage