Biospheric Sciences Seminar: Diane Debinski

Professor, Ecology, Evolution and Organismal Biology, Iowa State University

Grasslands are some of the most productive biomes on earth, producing grain, dairy products, and meat for human consumption. They also provide habitat for a broad range of wildlife species and beneficial insects. Grasslands respond to environmental changes much more rapidly than forested systems, and accordingly can serve as early warning indicators for how ecosystems respond to climate change. Dr. Debinski has been conducting long-term field studies associated with biodiversity assessment within grasslands of the Midwestern tallgrass prairie as well as montane meadows within the Greater Yellowstone Ecosystem. In both of these grassland systems she has collected data on plant distribution and abundance. The montane meadow sampling sites were selected using Landsat and SPOT data to classify habitats along the hydrological gradient. Her goal is to examine the resilience of grasslands to seasonal and interannual variation in temperature and precipitation, with a focus on characterizing responses to extreme climatic conditions such as drought and then assessing the vulnerability of these systems under climate change conditions. She is visiting NASA to discuss options for using a combination of aerial and remotely sensed imagery, spectroradiometer data, and ground-based surveys to quantify productivity, vegetation composition and vegetation structure within grassland ecosystems. Both of these systems are vulnerable to change via woody encroachment. Landsat data will be used to quantify long-term trends. MODIS data will be used to quantify seasonal variation at a fine temporal scale. Hyperspectral data and aerial imagery will be utilized to quantify change at a fine spatial scale. This multi-sensor analysis will provide short-term (decadal) indications of how climatic variation is manifested in human dominated as well as pristine environments and to predict those grasslands that will be most vulnerable to climate change. Short-term indicators will be valuable in tracking longer-term (multi-decade) changes, understanding climate changes at a global scale, and developing better remote-sensing tools for tracking such changes.