Forecasting Arctic Vegetation (FAV):
Observed Vegetation and Land Cover Change in Alaskan Arctic Tundra
Principal Investigator:
Dr. Patrick J. WebberProject Manager: Dr. Craig Tweedie
Project Abstract: This project is investigating the interaction between vegetation and land cover change, climate change, and surface disturbance. FAV is focused between community and landscape scales.
To date, the FAV project has focused on the re-sampling of marked plots established in 1972 during IBP at Barrow and in 1975 during the RATE program at Atqasuk. Analyses to date have assessed the successional direction of community change since the first sampling of each plot. Results suggest wet and mesic sites change to a greater extent than dry sites and changes at Barrow have been greater than those at Atqasuk. Most of the changes documented are consistent with the thaw lake cycle sensu Britton 1965, Billings and Peterson (1975) and Webber (1978). Following our plot-based resampling effort and also a resampling of the former IBP Site 4 microtopographic grid, the focus of field efforts this year was a re-resampling of former IBP Site 4. This is a ca. 4.3ha site marked with stakes on a 10m x 10m grid design. Re-sampling efforts repeated former measurements made in 1972-73 including a detailed vegetation map, and recording of seasonal thaw depth, microtopographic position and relative elevation at each of the 10m grid points across the site. Preliminary analyses suggest a general drying of the grid since the early 1970's.
In summer 2001 Steve Rewa began fieldwork towards his masters thesis on the long term recovery of off-road vehicle disturbance near Barrow. Rewa sampled 25 track systems at four localities including track systems formerly studied in the early 1970's by Peterson near former IBP site 1 and Abele at a CRREL test track near West Twin Lake. Measurements included plot and landscape scale vegetation sampling and classification, seasonal thaw depth, soil moisture content and microtopographic variation.
Late in the summer of 2000 we acquired, through collaboration with BASC, panchromatic and multispectral IKONOS imagery for the Barrow Environmental Observatory. This summer we developed a hierarchical classification of the imagery including a series of decision rules for each class. We have been working on the classification as part of a contractual agreement with a former masters student of our working group Brian Noyle at Pacific Meridian Resources/Space Imaging in Ann Arbor, Michigan. Our classification has yielded extraordinary high resolution. We have been able to classify separately, polygon troughs, rims and low centers. We post-phoned an accuracy assessment of the classification until summer 2002 when it is hoped real-time survey grade DGPS will be available in Barrow.