Effect of Saturated Near Surface on Nitrate and Ammonia Nitrogen Losses in Surface Runoff at the Loess Soil Hillslope

Table 2

Means of nutrient concentration with runoff under different near-surface soil moisture conditions.

Treatment^†	Concentration in surface runoff			Losses in surface runoff
	NO3^−-N	NH4^+-N	NO3^−-N	Loss as a percentage of N input	NH4^+-N	Loss as a percentage of N input
	mg/L		kg ha^-1		kg ha^-1
CFD	7.94c^‡	0.45b	7.27d		0.42c
CSA	14.14c	0.76a	21.11c		1.14b
LFD	11.9c	0.46b	8.28d	6.9	0.32d	0.27
LSA	26.36b	0.73a	41.02b	34.2	1.14b	0.95
HFD	11.02c	0.17c	9.36d	3.9	0.15e	0.06
HSA	63.22a	0.73a	101.56a	42.3	1.18a	0.49

^†C, control fertilizer treatment (no fertilizer input); L, low fertilizer treatment/input (120 kg N ha⁻¹); H, high fertilizer treatment/input (240 kg N ha⁻¹). FD, free drainage hydraulic gradient; SA, saturated hydraulic gradient.
^‡Mean values with a fertilizer treatment followed by any identical letters are not statistically different at the 95% confidence level according to LSD tests.