PARENT SESSION
Oral Session #71: Remote Sensing and GIS.
Presiding: J.D. Allan
Wednesday, August 7. 1:00 PM to 4:45 PM. Palo Verde Room, Radisson.
Scaling evapotranspiration measurements along the Middle Rio Grande riverine corridor.
McDonnell, Dianne*,1,2, Dahm, Cliff1, Coonrod, Julie2, Thibault, Jim1, Cleverly, James1, Schmidt, Mark2, 1 University of New Mexico, Albuquerque, NM2 University of New Mexico, Albuquerque, NM
ABSTRACT- The goal of this research was to determine whether a remotely sensed vegetation index related to Leaf Area Index (LAI) could be used to calculate evapotranspiration (ET) along the Middle Rio Grande riparian corridor. Both ground-based and remote sensing techniques were used to estimate riparian zone ET at the plot scale by combining state-of-the-art micrometeorological measurements with ground based and satellite based determination of LAI. Data collected at micrometeorological towers at four sites formed the basis for calculating ET using the eddy covariance method. Resulting ET estimates were strongly correlated to field based measurements of LAI using LICOR LAI meters taken at the four tower sites and eight additional study sites. Using the relationship between LAI and ET, ET was calculated for all twelve study sites. The relationship between ET calculated at the 12 sites was then compared to remotely sensed vegetation indices using Landsat 7 Enhanced Thematic Mapper imagery. The relationships found between remote sensing vegetation indices and ET were encouraging, although they were different between salt cedar and cottonwood stands. The results showed that a remotely sensed vegetation index could be used to determine ET along the riparian corridor provided a good vegetation classification was available.
KEY WORDS: Remote Sensing, Evapotranspiration, Leaf Area Index, Rio Grande