Modeling actual evapotranspiration of Acer rubrum from a rooted cutting to an 8 m tall tree in a humid climate.

摘要

Rooted cuttings, 0.44 m tall, of Acer rubrum 'Florida Flame' were transplanted into 26 L containers and placed in weighing lysimeters in March 2001. Trees were transplanted into progressively larger containers annually through February 2005, until residing the final growing season in 1.4 m diameter containers. Actual evapotranspiration (ETA) was determined daily along with calculation of reference evapotranspiration (ET_O) based on the ASCE 2000 Penman-Monteith equation. Trunk circumference at 15 and 30 cm above soil level, along with that below the first major branch were recorded about every 3 weeks during the growing season. Canopy width and tree height were similarly recorded. Normalized ET_A by trunk cross sectional areas and projected canopy area were linearly related to ET_O. Mean errors between predicted and measured ET_A ranged from 12 to 16%. Normalizing by projected canopy area was the most precise. However normalizing by cross sectional area at the canopy base was the most accurate.