HR: 0800h
AN: H31E-1342    [Abstracts]
TI: Estimating Changes in Forest Height and Structure in Hubbard Brook Experimental Forest Using LIDAR Remote Sensing
AU: * ODell, K
EM: kateo@geog.umd.edu
AF: University of Maryland, Department of Geography, College Park, MD 20742 United States
AU: Dubayah, R
EM: dubayah@umd.edu
AF: University of Maryland, Department of Geography, College Park, MD 20742 United States
AU: Hofton, M
EM: mhofton@umd.edu
AF: University of Maryland, Department of Geography, College Park, MD 20742 United States
AU: Blair, J B
EM: James.B.Blair@nasa.gov
AF: NASA Goddard Space Flight Center, Laser Remote Sensing Branch, Greenbelt, MD 20771 United States
AU: Hurtt, G
EM: george.hurtt@unh.edu
AF: Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824 United States
AB: Understanding forest successional state and dynamics is important from the perspective of ecological modeling and management but presents challenges for remote sensing. In this paper we explore the efficacy of medium footprint waveform recording lidar remote sensing in detecting forest growth and successional status in a northeastern temperate mixed deciduous forest. Using data from the Laser Vegetation Imaging Sensor (LVIS) over Hubbard Brook Experimental Forest in northern New Hampshire, USA, we evaluated the changes in forest height and vertical structure that occurred between 1999 and 2003. LVIS is an airborne, medium-footprint (20- to 25-meter diameter), full waveform-recording lidar that has flown several missions since 1998 over various ecosystems. The system is unique amongst airborne sensors in that it digitally records the shape of the returning laser echo, or waveform, after its interaction with the various reflecting surfaces of the earth (leaves, branches, ground, etc.), providing a true 3-dimensional record of the surface structure. The Hubbard Brook Experimental Forest (HBEF) is a 3,160-hectare reserve located in the White Mountain National Forest of New Hampshire. It was established by the U.S. Forest Service in 1955 for hydrological research, and is now part of the NSF Long Term Ecological Research (LTER) network. In order to determine how the forest has changed, we examined medium-footprint lidar return waveform data from both years and compared changes in LVIS-derived canopy height and structural metrics (i.e. the height above the ground where 50% of waveform energy occurred). Additionally, footprints that had larger than expected height changes were examined to discover if observed differences were related to true disturbance, such as tree fall, or were the result of system and processing errors.
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0480 Remote sensing
SC: Hydrology [H]
MN: Fall Meeting 2005