HR: 0830h
AN: G11A-0241    [PDF]
TI: Using Airborne LIDAR Data to Determine Old vs. Young Cottonwood Trees in the Riparian Corridor of the San Pedro River
AU: * Farid, A
EM: farid@hwr.arizona.edu
AF: Department of hydrology and water resources, university of arizona, 1133 E. North Campus Drive, tucson, az 85721 United States
AU: goodrich, d
EM: dgoodrich@tucson.ars.ag.gov
AF: USDA-ARS-SWRC, SW Watershed Research Center, 2000 E. Allen Road, tucson, az 85719 United States
AU: Sartori, m
EM: michaels@ufl.edu
AF: department of civil and coastal engineering, university of florida, 345 Weil Hall, P.O. Box 116580, Gainesville, fl 32611 United States
AU: Sorooshian, S
EM: soroosh@hwr.arizona.edu
AF: department of civil and environmental engineering, university of California - Irvine, 305 Rockwell Engineering Center, Irvine, ca 92697 United States
AB: Quantification of vegetation patterns and properties is needed to determine their role in the landscape and to develop management plans to conserve natural resources. Vegetation patterns can be mapped from the ground, or by using aerial photography or satellite imagery. However, quantifying the physical properties of vegetation patterns with ground-based or remote sensing technology is difficult, time consuming, and often costly. Digital data from an airborne lidar (light detecting and ranging) instrument offers an alternative method for quantifying vegetation properties and patterns. Using lidar, a study was conducted in the San Pedro National Riparian Conservation Area in an attempt to differentiate young and old Cottonwood trees in southeastern Arizona as young and old cottonwoods have significantly different water use per unit area of canopy. The lidar data was acquired in June 2003, using Optech's ALTM (Airborne Laser Terrain Mapper), during flyovers conducted at an altitude of 750 m. It has been demonstrated that the height of old and young cottonwood canopies can be measured by using lidar. Canopy heights measured with the lidar show a good degree of correlation with ground-based measurements. Methodologically, the first step required is to differentiate old from young cottonwood canopies by the differences in canopy height obtained from lidar data. In addition to vegetation heights, spatial patterns of crown area, canopy cover, and intensity of return laser pulse are measured for both old and young cottonwood trees with the lidar data. The second stage of this study demonstrates that these other parameters of old and young cottonwood trees, when extrapolated from lidar, are significantly different. This study indicates the potential of airborne lidar data to distinguish between different ages of cottonwood forest canopy for large areas quickly and quantitatively.
DE: 1200 GEODESY AND GRAVITY
SC: Geodesy [G]
MN: 2003 Fall Meeting