OREGON STATE UNIVERSITY

LARSE

The Laboratory for Applications of Remote Sensing in Ecology (LARSE) is a joint research effort of the USDA Forest Service PNW Research Station and the Department of Forest Ecosystems and Society. Activity began in 1989 with a concentration on using digital imagery to characterize forest structure in the Pacific Northwest Douglas-fir/western hemlock zone. Within a few short years, Landsat-based maps of forest structure were being directly incorporated into ecological analyses and models operating at landscape to regional scales. LARSE regularly employs between 10 to 20 scientists in a variety of positions, including permanent staff, post-docs, faculty research assistants, graduate students, student workers, and international scholars.

Justin Braaten is a PhD student in the LARSE lab. His work there includes development of automated image processing procedures to integrate satellite data from multiple Landsat sensors into long, harmonious, 43-year spectral chronologies. The data enhances understanding of landscape-scale forest dynamics by providing consistent annual spectral measurements related to forest structure and productivity over very large regions. The long time series tracks spatiotemporal trends and patterns in forest disturbance and recovery from harvest, fire, drought, insect, and disease. The banner image above is a compressed example of the change occurring between three time periods (1984, 1998, 2012), as represented by write function memory insertion. It renders land that has changed from one period to the next with color, and areas that have not, with grayscale. The image subset is from an interesting area on the Olympic Peninsula (WA) that shows variation in forest management practices in private, state, Forest Service, and National Park Service land. Tan colors represent forest recovery over the entire 28-year period (disturbed prior to 1984), shades of blue/green are disturbances that have occurred more recently, and purplish colors indicate older disturbances that happened between the mid-eighties and early nineties. Take note of the differences in disturbance shape, size, continuity, and location over the landscape, and through time, as indicated by the color.