Elevated atmospheric CO reduces yield-scaled N O fluxes from subtropical rice systems: Six site-years field experiments.

Increasing levels of atmospheric CO are expected to enhance crop yields and alter soil greenhouse gas fluxes from rice paddies. While elevated CO ( ) effects on CH emissions from rice paddies have been studied in some detail, little is known how might affect N O fluxes or yield-scaled emissions. Here, we report on a multi-site, multi-year in-situ FACE (free-air CO enrichment) study, aiming to determine N O fluxes and crop yields from Chinese subtropical rice systems as affected by .

[Canopy spectral characteristics of different rice varieties].

By using spectroradiameter, canopy spectral characteristics such as reflection rate (alpha), absorption rate (tau), transmission rate (beta), and extinction coefficient(K) of different rice varieties were analyzed and compared. The results showed the canopy spectral characteristics were significantly different among different rice varieties, especially under blue radiation (400-510 nm). In addition, these dissimilarities were more obvious in the late stage of growth period.