. 2018 Jan 22;8:2260. doi: 10.3389/fpls.2017.02260

Table 2.

Average NO₃-N leachate and cumulative gaseous N₂O-N and NH₃-N fluxes pre-fertilization (Oct–May) and post-fertilization (May–Oct), the percentage of fertilizer N diverted into gaseous N loss pathways, and average corn yield.

Treatment	Fertilizer N (kg N ha⁻¹)	NO₃-N Leachate (Oct–May) (mg L⁻¹)	NO₃-N Leachate (May–Oct) (mg L⁻¹)	Cumulative N₂O-N (Oct–May) (kg N ha⁻¹)	Cumulative N₂O-N (May–Oct) (kg N ha⁻¹)	Cumulative NH₃-N (Oct–May) (kg N ha⁻¹)	Cumulative NH₃-N (May–Oct) (kg N ha⁻¹)	Apparent Fertilizer lost as % NH₃-N^†	Apparent Fertilizer lost as % N₂O-N^†	Corn Yield (Mg ha⁻¹)
ORGANIC COVER CROP COMPARISONS
Hairy vetch	0	443^a	217^a	0.79^a	1.79^a	−4.01^a	8.71^a	–	–	4.30^a
Wheat	0	222^c	19^b	1.16^a	2.13^a	−4.40^a	7.27^a	–	–	1.46^b
Bi-culture	0	249^b	106^a	0.65^a	2.05^a	28.09^a	18.91^a	–	–	4.92^a
ORGANIC HAIRY VETCH FERTILIZER COMPARISONS
0 N	0	443^a	217^a	0.79^a	1.79^b	−4.04^a	8.71^c	–	–	4.30^b
N-Credit	154	468^a	249^a	1.99^a	3.10^b	22.75^a	12.81^b	2.66	0.63	8.85^a
Organic N	164	304^a	307^a	1.31^a	4.47^a	7.62^a	39.09^a	18.52	1.43	9.91^a
CONVENTIONAL WHEAT FERTILIZER COMPARISONS
0 N	0	263^a	63^b	1.97^a	1.83^a	13.69^b	−5.80^b	–	–	6.66^b
Urea N	168	227^a	602^a	3.04^a	3.54^a	36.95^a	24.29^ab	17.92	1.02	16.87^a
Organic N	168	154^a	109^b	0.86^a	5.05^a	−8.10^c	43.07^a	29.09	1.92	12.62^ab

Different letters indicate significant difference (p < 0.05).