Code 614.4 Branch Seminar

Oregon State University

Speaker:Dr Joanne Nightingale, Post-doctoral research fellow, Department of Forest Science, College of Forestry Abstract At the regional and continental scale, ecologists have theorized that spatial variation in biodiversity can be interpreted as a response to differences in climate. To test this theory, we assumed that ecological constraints associated with current climatic conditions (2000-2004) might best be expressed through some measure of gross primary production (GPP) derived with remotely sensed data. To evaluate current patterns in tree diversity across the contiguous U.S.A. we acquired information on tree composition from the United States Forest Inventory and Analysis program recorded on more than 174,000 survey plots distributed within 2693 cells of 1000 km2 . Our forest productivity measures varied from simple vegetation indices acquired at 16-day intervals with MODIS (MODerate resolution Imaging Spectro-radiometer), to 8 and 10-day GPP products derived with minimal climatic data (MODIS) and SPOT (Systeme Pour l‚Observation de la Terre- Vegetation), to 3-PGS (Physiological Principles Predicting Growth with Satellites) that required both climate and soil data. Across the contiguous U.S.A., modeled predictions of productivity accounted for between 51% and 77% of the recorded spatial variation in tree diversity, which ranged from 2 to 67 species per hectare. Only 3-PGS predictions fit the theorized unimodal function by recognizing highly productive forests in the Pacific Northwest that support limited tree diversity. Other models predicted a continuous steep rise in tree diversity with increasing productivity, and did so with generally better or near equal precision with fewer data requirements. Short bio-sketch of the speaker: Joanne Nightingale is a post-doctoral research fellow in the College of Forestry at Oregon State University. Her research focuses on examining the impact of global climate changes on the productivity and diversity of forests across the United States. Joanne received her BSc, Honours and Ph.D. degrees from the University of Queensland in Australia in 2005. Her research interests include ecosystem modeling, application of remote sensing and modeling to monitor land surface properties and validation and evaluation of the MODIS products used within these models. Point of Contact: Petya Entcheva Campbell, Ph.D. (pcampbel@pop900.gsfc.nasa.gov) Joint Center for Earth Systems Technology (JCET), University of Maryland Baltimore County GSFC/NASA, Biospheric Sciences Branch, Code 614.4 NASA Goddard Space Flight Center, Building 33, Room G313, Greenbelt, Maryland 20771 Phone: 301 614 6784 Fax: 301 614 6695