Rd. Mac Nish et al., Comparison of riparian evapotranspiration estimates based on a water balance approach and sap flow measurements, AGR FOR MET, 105(1-3), 2000, pp. 271-279
Estimates of evapotranspiration (ET) from riparian vegetation along a 122m
reach of the San Pedro River using both a water balance approach and by sca
ling up sap flow measurements are compared. A sensitivity analysis was perf
ormed on the components of the water balance to assess the effects of measu
rement errors on estimates of ET using this method. It was concluded that b
y reducing the error in three key components to less than 5%, riparian ET c
ould be estimated to an accuracy of 20-25% using the water balance method.
The analysis also indicated that random measurement errors up to 10% in the
water balance measurements would explain the difference between the water
balance and sap flow ET estimates. Demonstrating agreement given reasonable
error bounds provides confidence in the accuracy of both methods. (C) 2000
Elsevier Science B.V. All rights reserved.