Aerial Nitrogen Fluxes and Soil Nitrate in response to Fall-Applied Manure and Fertilizer Applications in Eastern South Dakota
Table 2
Soil, leaf, grain, and yield measurements (±standard error)z based on treatment, year, and growth stage.
Parameter
Treatment
Mean
Year
Growth stage
Manure with bedding
Manure only
Urea
No fertilizer
Total soil nitrate nitrogen in the top 0–60 cm of soil (kg·ha−1)
Y1
Preplant
153.3 ± 19.5
155.1 ± 19.8
304.1 ± 38.7
151.9 ± 19.4
181.2 ± 14.5
a
V6
67.3 ± 16.6
50.2 ± 12.4
109.7 ± 27.1
57.5 ± 14.2
66.5 ± 8.8
b
Postharvest
57.3 ± 7.5
44.5 ± 5.9
63.7 ± 8.4
34.8 ± 4.6
48.5 ± 4.0
bc
Mean
83.2 ± 9.9
69.7 ± 8.3
127.5 ± 15.2
66.6 ± 8.0
83.4 ± 5.8
aa
Y2
Preplant
182.7 ± 23.3
172.2 ± 21.9
422.3 ± 53.8
159.7 ± 20.3
213.6 ± 17.1
a
V6
39.2 ± 9.7
38.7 ± 9.7
43.4 ± 10.7
44.7 ± 11.1
40.6 ± 5.3
bc
Postharvest
34.3 ± 4.5
35.2 ± 4.6
37.5 ± 4.9
38.8 ± 4.8
35.7 ± 2.9
c
Mean
62.1 ± 7.4
61.2 ± 7.3
87.5 ± 10.5
63.5 ± 7.6
67.5 ± 4.7
bb
Y1Y2
Mean
71.7 ± 6.3 b
65.1 ± 5.7 b
105.3 ± 9.2 a
64.9 ± 5.7 b
Surface soil nitrate nitrogen in the top 0–15 cm of soil (kg·ha−1)
Y1
Preplant
40.8 ± 6.6
41.7 ± 6.8
116.3 ± 18.9
35.0 ± 5.7
55.9 ± 4.9
a
V6
14.4 ± 2.3
7.7 ± 1.2
16.8 ± 2.7
7.5 ± 1.2
10.8 ± 1.0
cd
Postharvest
28.5 ± 4.6
21.2 ± 3.4
26.4 ± 4.3
17.4 ± 2.8
22.8 ± 2.2
b
Mean
25.4 ± 2.5
18.8 ± 1.9
36.9 ± 3.7
16.5 ± 1.6
23.1 ± 1.3
Y2
Preplant
67.1 ± 10.9
55.1 ± 8.9
189.0 ± 30.7
45.7 ± 7.4
74.5 ± 7.1
a
V6
11.7 ± 1.9
8.6 ± 1.4
9.8 ± 1.6
8.7 ± 1.4
9.6 ± 0.9
d
Postharvest
14.6 ± 2.4
13.3 ± 2.2
15.7 ± 2.6
15.4 ± 2.5
14.6 ± 1.4
c
Mean
22.4 ± 2.2
18.4 ± 1.8
30.5 ± 3.0
18.2 ± 1.8
21.8 ± 1.3
Y1Y2
Mean
23.8 ± 1.7 b
18.5 ± 1.3 bc
33.5 ± 2.4 a
17.3 ± 1.2 c
Soil water nitrate nitrogen concentration at 120 cm soil depth between planting and V6 growth stages (mg·L−1)
Y1
9.0 ± 3.2
16.6 ± 3.2
12.1 ± 3.2
12.4 ± 3.2
12.5 ± 3.2
a
Y2
3.7 ± 3.4
9.1 ± 3.3
8.5 ± 3.4
4.5 ± 3.3
9.5 ± 3.3
b
Y1Y2
Mean
6.35 ± 3.3
12.85 ± 3.3
10.3 ± 3.3
8.45 ± 3.3
Corn leaf nitrogen concentration, g·kg−1
Y1
Preplant
29.3
29.9
31.3
27.7
29.6 ± 0.8
a
V6
27.9
27.2
29
28.4
28.1 ± 0.8
a
Postharvest
15.0
14.5
14.5
12.6
14.2 ± 0.8
b
Mean
24.1 ± 0.9
23.9 ± 0.9
25.0 ± 0.9
22.9 ± 0.9
23.9 ± 0.5
aa
Y2
Preplant
28.5
27.3
31
26.4
28.3 ± 0.8
a
V6
17
16.9
20.6
15.6
17.5 ± 0.8
b
Postharvest
10.6
10.8
10.3
10.4
10.5 ± 0.8
c
Mean
18.7 ± 0.9
18.3 ± 0.9
20.6 ± 0.9
17.5 ± 0.9
18.8 ± 0.5
bb
Y1Y2
Mean
21.4 ± 0.7
21.1 ± 0.7
22.8 ± 0.7
20.2 ± 0.7
Corn grain nitrogen concentration, g·kg−1
Y1
13.3 ± 0.6
12.2 ± 0.4
13.6 ± 0.7
11.9 ± 0.2
12.8
Corn yield, Mg·ha−1
Y1
12.0 ± 1.0
10.8 ± 1.0
12.5 ± 0.5
10.8 ± 0.5
11.5
zMean ± SE = estimated mean ± standard error obtained from least squared means table. Different letters in means among the treatments indicate significant difference at within a variable type. Double letters indicate significant differences between yearly means. The absence of letters indicates between means.