Potential of Controlled Irrigation and Drainage for Reducing Nitrogen Emission from Rice Paddies in Southern China

Figure 4

The change of the concentration of -N during submergence in 2010. CK indicates alternate drying and wet irrigation; T1, T2, T3, and T4 denote the submergence at tillering stage, jointing-booting stage, panicle initiation stage, and milky stage, respectively. Vertical bars represent ± standard error (SE) of the mean.

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