|Pinter Jr, Paul|
|Leavitt, S - UNIV OF ARIZONA|
|Brooks, T - UNIV OF ARIZONA|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 28, 1997
Publication Date: N/A
Technical Abstract: Field-grown spring wheat (Triticum aestivum L. cv. Yecora rojo) was exposed to CO2 concentrations enriched to 200 umol/mol above ambient (ca. 370 umol/mol) using free-air CO2 enrichment (FACE) apparatus. Half of each main CO2 plot received ample nitrogen (350 KgN/ha), while the other half received 70 kgN/ha, intended to provide a low-N stress. Measurements were made of net radiation, soil heat flux, soil temperature, canopy temperature, air wet and dry bulb temperatures, leaf wetness, and wind speed. Sensible heat flux was calculated from the wind and temperature measurements, and evapotranspiration (ET) was determined as the residual of net radiation minus soil heat flux minus sensible heat flux. The FACE treatment reduced ET about 6 and 16% at the high and low nitrogen levels, respectively.