Measurement and simulation of diurnal variations in water use efficiency and radiation use efficiency in an irrigated wheat-maize field in the North China Plain

摘要: Abstract Quantifying diurnal patterns of water use efficiency (WUE) and radiation (RUE) for wheat maize is important assessing by plants crop productivity. Water carbon dioxide fluxes from an irrigated wheat-maize double-crop field November 2002 to October 2003 were measured using the Eddy Covariance method. Evident differences observed between WUE maize. The values peaked near 9, 15 12 mg CO2 g H2O in morning, then decreased linearly with time recovered late afternoon (4:00pm) before sunset March, April May, respectively. increased after sunrise retained stable 6, 14 mid-morning mid-afternoon (10:00am –2:00pm) slowly until July, August September, Similar RUE Over three months study, averaged was 1...