US-IALE 2018 has ended
Back To Schedule
Wednesday, April 11 • 2:15pm - 2:30pm
SYMPOSIA-13: Identifying Defoliation-based Disturbances in Forests Around Western Lake Superior Using a 30-year Landsat-based Phenoclimatology Analysis

Sign up or log in to save this to your schedule, view media, leave feedback and see who's attending!

AUTHORS: Matthew Garcia*, Philip A. Townsend – Department of Forest and Wildlife Ecology, University of Wisconsin-Madison; Brian R. Sturtevant, Institute for Applied Ecosystem Studies, Northern Research Station, USDA Forest Service

ABSTRACT: We developed novel methods for processing dense Landsat time series over the 1984-2013 period for the forests of the western Lake Superior region, USA. These methods allow us to derive mean annual phenology, to attribute deviations from that mean phenology to interannual variability in climatological conditions, and to examine further deviations from the expected phenoclimatology attributable to disturbance. The heavily-forested area of northeastern Minnesota along Lake Superior has seen numerous disturbance events within our study period: large and small fires, severe wind events, drought periods, and both focused and widespread insect outbreaks. While the more severe disturbances are often easier to identify and attribute to known causes, potentially mild and often slow-building events such as insect defoliation and drought stress can be more challenging to assess from the remote sensing perspective. We have documented observations of outbreaks of two defoliating insects, the eastern spruce budworm (Choristoneura fumiferana) and the forest tent caterpillar (Malacosoma disstria), within our study area and period. Outbreak events for both of these agents were identified in the Landsat image record and led to clear departures from typical or expected interannual variability in their respective host phenology. These disturbances can be tracked from the initial event through the forest regeneration period, helping us better understand the cycles of forest disturbance and recovery that result from quasi-periodic defoliating insect outbreaks that are comparatively mild relative to stand-replacing disturbances such as fire or logging.

Wednesday April 11, 2018 2:15pm - 2:30pm CDT
Water Tower Parlor