Luo Weihong, Yoshimoto Mayumi, Dai Jianfeng, Zhu Jianguo, Han Yong, Liu Gang
MOA Key Laboratory of Crop Growth Regulation, Nanjing Agricultural University, Nanjing 210095, China.
Ying Yong Sheng Tai Xue Bao. 2003 Feb;14(2):258-62.
The change of crop canopy energy balance will affect crop growth and development and its water use efficiency. In this study, the FACE system (setup at at Anzhen, Wuxi, Jiangsu Province in 2001) was used to investigate the effects of FACE on rice canopy energy balance. The rice canopy microclimate observations were carried out from August 26 to October 13, 2001 when the rice crops were at the heading to maturing stage. The results showed that the maximum difference of rice canopy sensible and latent heat fluxes between ambient and FACE occurred at the same time of minimum air humidity, i.e., at about 14:00. From flowering to maturing stage, the maximum difference of rice canopy sensible and latent heat flux between FACE and ambient varied between 12-55 J.m-2.s-1 and -15(-)-65 J.m-2.s-1, respectively. The daytime total canopy sensible and latent heat fluxes of FACE were higher and lower than those of ambient, respectively, throughout flowering to maturing stage. The differences of daytime total canopy sensible and latent heat fluxes between ambient and FACE increased with the increase of net radiation above canopy during the same development stage, but decreased with the progress of the development stage. From flowering to maturing stage, the average difference of daytime total canopy latent heat flux between ambient and FACE was about 6.7%. FACE increased and decreased the ratio of daytime total canopy sensible and latent heat flux to daytime total net radiation above canopy, respectively, the ratio differences between FACE and ambient were 5.5%.
作物冠层能量平衡的变化会影响作物的生长发育及其水分利用效率。本研究利用自由空气CO₂浓度增高（FACE）系统（于2001年在江苏省无锡市安镇设置）来研究FACE对水稻冠层能量平衡的影响。在2001年8月26日至10月13日水稻处于抽穗至成熟阶段时，进行了水稻冠层小气候观测。结果表明，水稻冠层显热通量和潜热通量在环境条件与FACE条件下的最大差异出现在空气湿度最低的同一时刻，即大约14:00。从开花期到成熟期，FACE与环境条件下水稻冠层显热通量和潜热通量的最大差异分别在12 - 55 J·m⁻²·s⁻¹和 - 15(-)-65 J·m⁻²·s⁻¹之间变化。在整个开花至成熟阶段，FACE条件下白天冠层总显热通量高于环境条件下的，而潜热通量则低于环境条件下的。在同一发育阶段，环境条件与FACE条件下白天冠层总显热通量和潜热通量的差异随着冠层上方净辐射的增加而增大，但随着发育阶段的推进而减小。从开花期到成熟期，环境条件与FACE条件下白天冠层总潜热通量的平均差异约为6.7%。FACE分别增加和降低了白天冠层总显热通量和潜热通量与冠层上方白天总净辐射的比值，FACE与环境条件下的比值差异为5.5%。
