Table 3 Significance of NO3–-N content in different soil layers under different fertilization timing sequences in 2020–2021.
Growth stage | Soil depth | 2020 Soil NO3–-N content (mg/kg) | 2021 Soil NO3–-N content (mg/kg) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
S1 | S2 | S3 | S4 | S5 | S6 | S7 | S1 | S2 | S3 | S4 | S5 | S6 | S7 | ||
FBS | 0–20 | 16.44a | 16.15a | 17.17a | 16.25a | 15.85a | 15.92a | 14.47a | 16.81d | 18.31b | 17.75c | 18.11bc | 19.10a | 19.16a | 15.93e |
20–40 | 18.87a | 19.15a | 19.24a | 19.40a | 18.21a | 18.58a | 16.74a | 20.29b | 18.12d | 18.40d | 19.11c | 21.31a | 19.30c | 17.25e | |
40–60 | 17.85a | 16.42a | 17.76a | 16.53a | 16.45a | 16.34a | 16.60a | 20.33b | 18.94d | 21.49a | 19.76c | 17.37e | 19.06d | 16.14f | |
FFS | 0–20 | 18.78de | 19.53ab | 18.49e | 19.05cd | 19.21bc | 19.81a | 17.37f | 18.75bc | 20.07a | 19.26b | 19.26b | 20.50a | 20.70a | 17.55d |
20–40 | 19.95d | 21.28b | 20.25d | 20.85c | 22.30a | 21.24b | 19.10e | 20.43e | 22.64b | 20.77de | 21.33cd | 24.14a | 22.07bc | 19.51f | |
40–60 | 21.54b | 19.01d | 22.18a | 20.31c | 18.26e | 19.22d | 17.19f | 22.72b | 19.99d | 23.43a | 21.05c | 19.20e | 20.12d | 18.04f | |
PBS | 0–20 | 15.22d | 16.20bc | 15.13d | 15.94c | 16.58ab | 16.71a | 14.25e | 15.84d | 18.26a | 15.28e | 16.28cd | 17.34b | 18.64a | 14.27f |
20–40 | 16.84e | 18.32ab | 17.14de | 17.66cd | 18.81a | 18.14bc | 16.06f | 17.13d | 19.24b | 17.28d | 18.36c | 20.66a | 18.96b | 16.48e | |
40–60 | 18.15a | 16.89b | 18.31a | 17.92a | 16.23c | 17.24b | 15.12d | 20.33b | 16.90d | 21.34a | 18.38c | 16.37e | 17.29d | 15.16f | |
BOS | 0–20 | 17.26b | 17.68ab | 17.15b | 17.55ab | 16.96b | 18.00a | 17.05b | 17.98ab | 18.94ab | 18.31ab | 18.75ab | 18.92ab | 19.04a | 16.82b |
20–40 | 18.58bc | 19.67a | 18.71b | 19.20a | 19.53a | 19.33a | 18.23c | 20.77a | 20.45a | 20.98a | 21.31a | 21.42a | 21.06a | 18.44b | |
40–60 | 18.12b | 17.62cd | 18.83a | 18.35b | 17.51d | 17.98bc | 17.45d | 20.41a | 17.92b | 21.02a | 17.48b | 17.22b | 17.73b | 16.75b | |
