Soil horizons
|
Soil properties
|
N addition treatments
|
---|
CK
|
LN
|
MN
|
HN
|
---|
Oa+e horizons
|
Total N (g kg−1)
|
1.65 ± 0.12b
|
1.77 ± 0.07b
|
1.85 ± 0.32a
|
1.96 ± 0.10a
|
δ15N (‰)
|
− 1.47 ± 0.52b
|
− 0.89 ± 0.19ab
|
− 0.25 ± 0.58a
|
− 0.48 ± 0.10a
|
Total C (g kg−1)
|
39.92 ± 4.21a
|
42.64 ± 1.90a
|
39.12 ± 6.21a
|
42.60 ± 1.12a
|
δ13C (‰)
|
− 29.13 ± 0.11a
|
− 28.96 ± 0.28a
|
− 29.16 ± 0.28a
|
− 29.15 ± 0.20a
|
NH4+–N (mg kg−1)
|
45.54 ± 12.39b
|
85.12 ± 15.99ab
|
186.28 ± 85.75a
|
166.32 ± 85.43a
|
NO3−–N (mg kg−1)
|
9.88 ± 0.90b
|
9.66 ± 0.54b
|
17.52 ± 3.21a
|
14.11 ± 3.46ab
|
Mineral horizons
|
Total N (g kg−1)
|
0.19 ± 0.03b
|
0.21 ± 0.03b
|
0.29 ± 0.04a
|
0.26 ± 0.04ab
|
0–10 cm
|
δ15N (‰)
|
5.54 ± 0.93a
|
4.77 ± 0.69a
|
5.03 ± 0.70a
|
4.47 ± 0.55a
|
Total C (g kg−1)
|
5.15 ± 1.29a
|
4.07 ± 1.61a
|
4.02 ± 1.13a
|
5.13 ± 2.67a
|
δ13C (‰)
|
− 26.54 ± 0.30a
|
− 26.75 ± 0.25a
|
− 26.28 ± 0.19a
|
− 26.70 ± 0.17a
|
NH4+–N (mg kg−1)
|
6.14 ± 0.72b
|
8.01 ± 3.01b
|
13.47 ± 3.47a
|
12.64 ± 2.19a
|
NO3−–N (mg kg−1)
|
1.70 ± 0.21c
|
2.74 ± 0.16bc
|
3.14 ± 0.42b
|
5.02 ± 2.06a
|
10–20 cm
|
Total N (g kg−1)
|
0.08 ± 0.01a
|
0.08 ± 0.03a
|
0.08 ± 0.02a
|
0.09 ± 0.04a
|
δ15N (‰)
|
5.93 ± 0.36a
|
5.90 ± 0.87a
|
5.87 ± 0.72a
|
5.13 ± 0.52a
|
Total C (g kg−1)
|
1.41 ± 0.71a
|
1.26 ± 0.07a
|
1.18 ± 0.48a
|
1.18 ± 0.44a
|
δ13C (‰)
|
− 26.00 ± 0.44a
|
− 25.98 ± 0.03a
|
− 26.11 ± 0.38a
|
− 26.12 ± 0.25a
|
NH4+–N (mg kg−1)
|
3.52 ± 1.59a
|
4.05 ± 1.46a
|
4.78 ± 0.73a
|
4.54 ± 1.52a
|
NO3−–N (mg kg−1)
|
2.23 ± 0.75a
|
2.47 ± 0.41a
|
2.78 ± 0.52a
|
2.37 ± 0.45a
|
- Alphabet indicates the significant difference among different N addition treatments. Tukey’s HSD test (p < 0.05)