Greater effect of canopy conductance in regulating the energy partition above the maize field in arid northwest China
Article first published online: 17 JUL 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Volume 27, Issue 24, pages 3452–3460, 29 November 2013
How to Cite
Li, S., Kang, S., Zhang, L., Li, F., Du, T., Tong, L., Wang, S. and Lu, H. (2013), Greater effect of canopy conductance in regulating the energy partition above the maize field in arid northwest China. Hydrol. Process., 27: 3452–3460. doi: 10.1002/hyp.9413
- Issue published online: 23 OCT 2013
- Article first published online: 17 JUL 2012
- Accepted manuscript online: 18 MAY 2012 06:45AM EST
- Manuscript Accepted: 20 APR 2012
- Manuscript Received: 9 NOV 2011
- canopy conductance;
- evaporative fraction;
- Penman–Monteith model;
- spring maize
The partition of available energy into evapotranspiration affected by environmental and physiological factors is critical in understanding the water cycle and optimizing the water management in the field. Our study attempted to accurately quantify the environmental and physiological control on variability in evaporative fraction (EF) based on the Penman–Monteith model. The eddy covariance method was used to measure water flux over a canopy and then calculate the EF above a maize field in northwest China in 2007. Results indicate that the EF was lower in other growth stages than in the heading stage, so the EF value in the heading stage was taken as the standard value. The decreases in EF caused by canopy conductance and environmental factors were 0.176 and −0.026, accounting for 117% and −17% of the total difference in EF, respectively. Such results were mainly due to the following: (1) the variation of maize canopy conductance was greater than that of the environmental factors, such as air temperature, air humidity, wind speed and radiation; (2) the EF of the maize was more sensitive to variation in canopy conductance than the environmental factor. Our study revealed that crop physiological factor played an important role in determining the energy partition processes and reducing the sensible heat flux in the maize field. Copyright © 2012 John Wiley & Sons, Ltd.