Table 1 Physical and chemical properties (mean values ± SE, n = 3) of soil (depth of 0–10 cm) in each treatment in the Acer velutinum Bioss. stand before N addition (April 2015)
Soil properties | Treatment plots | |||
|---|---|---|---|---|
N0 | N1 | N2 | N3 | |
% Sand:Silt:Clay | 58:30:12 | 50:34:16 | 60:28:12 | 56:30:14 |
Bulk density (g cm−3) | 1.72 ± 0.02 | 1.77 ± 0.02 | 1.69 ± 0.01 | 1.70 ± 0.02 |
pH | 7.17 ± 0.01 | 7.20 ± 0.01 | 7.18 ± 0.01 | 7.12 ± 0.02 |
Electrical conductivity (dS m−1) | 0.89 ± 0.02 | 0.91 ± 0.01 | 0.90 ± 09 | 0.87 ± 03 |
Total N (g 100 g−1) | 0.38 ± 0.01 | 0.37 ± 0.01 | 0.37 ± 0.01 | 0.39 ± 0.01 |
\({\mathrm{NH}}_{4}^{+}\) (mg kg−1) | 4.13 ± 0.13 | 4.08 ± 0.09 | 4.15 ± 0.07 | 4.19 ± 0.10 |
\({\mathrm{NO}}_{3}^{-}\) (mg kg−1) | 4.87 ± 0.05 | 4.79 ± 0.07 | 4.71 ± 0.08 | 4.85 ± 0.10 |
OC (g 100 g−1 soil) | 3.94 ± 0.04 | 4.08 ± 0.18 | 3.85 ± 0.16 | 3.95 ± 0.06 |
Fine root biomass (g m−2) | 46.9 ± 0.95 | 47.1 ± 3.59 | 49.8 ± 0.73 | 46.8 ± 1.95 |