Regulating N Application for Rice Yield and Sustainable Eco-Agro Development in the Upper Reaches of Yellow River Basin, China

Table 6

NH₄⁺-N accumulative leaching at rice growth stages (kg·ha⁻¹).

Year	Treatment	Growth stage
		Seedling stage	Tillering stage	Jointing stage	Flowering stage	Heading stage	Harvest stage	Sum
2010	CK	0.15 a	0.35 c	0.15 d	0.11 c	0.26 b	0.06 d	1.09 c
	N300	0.18 a	1.09 a	0.77 a	0.53 a	0.67 a	0.34 b	3.58 a
	N240	0.14	1.23 a	0.71 ab	0.27 b	0.23 b	0.28 c	2.86 b
	RPN I	0.14 a	0.82 b	0.62 b	0.25 b	0.62 a	0.31 bc	2.76 b
	RPN II	0.13 a	0.84 b	0.41 c	0.43 a	0.57 a	0.43 a	2.81 b
2011	CK	0.08 c	0.23 d	0.17 c	0.12 d	0.16 d	0.08 d	0.84 b
	N300	0.18 a	1.27 a	0.65 ab	0.44 b	0.48 c	0.19 b	3.21 a
	N240	0.17 a	1.12 a	0.68 ab	0.32 c	0.72 b	0.14 c	3.15 a
	RPN I	0.15 ab	0.89 b	0.71 a	0.34 bc	0.64 b	0.21 b	2.94 a
	RPN II	0.10 c	0.64 c	0.51 b	0.62 a	0.81 a	0.36 a	3.04 a