Spatio-temporal characterization of insect defoliation through landsat images

Abstract

Effective modeling of forest susceptibility to defoliating insect outbreaks requires better understanding of outbreak dynamics, which includes detailed knowledge of the preand post-outbreak forest status as well as subsequent feedback mechanisms. In this paper, we strive to fill the forest status need by combining archived Landsat sensor data (pre-and post-outbreak) with different formats and dates of the U.S. Forest Service's Forest Inventory and Analysis (FIA) data (periodic [1970s, 1990s] and annual [2003][2004][2005][2006]). Specifically, we explore the utility of these FIA ground data for calibrating models of forest species and type abundance for mapping past forest composition in the Border Lakes Ecoregion (BLE) of Upper Midwest of the US. Model calibration results between Landsat reflectance and FIA ground data for both total forest basal area and balsam fir (Abies balsamea) relative basal area, a preferred host of the spruce budworm (SBW, Choristoneura fumiferana), were poor to moderate (R 2 adj 0.39 and 0.48, respectively). Results for aspen