Land cover change on the Seward Peninsula: the use of remote sensing to evaluate the potential influences of climate change on historical vegetation dynamics
Thesis (M.S.) University of Alaska Fairbanks, 2000Vegetation on the Seward Peninsula, Alaska, which is characterized by transitions from tundra to boreal forest, may be sensitive to the influences of climate change on disturbance and species composition. To determine the ability to detect decadal-scale structural changes in vegetation, Change Vector Analysis (CVA) techniques were evaluated for Landsat TM imagery of the Seward Peninsula. Scenes were geographically corrected to sub-pixel accuracy and then radiometrically rectified. The CVA results suggest that shrubbiness is increasing on the Seward Peninsula. The CVA detected vegetation change on more than 50% of the burned region on TM imagery for up to nine years following fire. The use of both CVA and unsupervised classification together provided a more powerful interpretation of change than either method alone. This study indicates that CVA may be a valuable tool for the detection of land-cover change in transitional regions between tundra and boreal forest.Abstract -- List of figures -- List of tables -- Acknowledgements -- Introduction -- Methods -- Results -- Radiometric rectification -- Fire disturbance -- Land cover change on the Seward Peninsula -- Potential false change -- Discussion -- CVA vs. unsupervised classification -- Fire disturbance -- Land cover change on the Seward Peninsula -- Challenges and limitations -- Improvements and future directions -- Literature cited
