Table 1 Soil characteristics and root decomposition rate constant (single exponential) under different forms of N fertilization and control treatments

Total C (mg C g⁻¹ soil)

28.1 (2.02)^a

27.6 (2.84)^a

27.4 (2.39)^a

28.6 (1.62)^a

29.7 (3.01)^a

31.3 (2.39)^a

Total N (mg N g⁻¹ soil)

2.03 (0.05)^b

2.90 (0.06)^a

2.73 (0.03)^ab

2.91 (0.07)^a

2.90 (0.03)^a

3.30 (0.07)^a

Soil C:N

13.5 (0.27)^a

10.7 (0.30)^ab

10.3 (0.19)^b

9.71 (0.24)^b

9.85 (0.38)^b

8.93 (0.63)^b

DOC (μg C g⁻¹ soil)

42.3 (5.01)^d

50.9 (6.13)^c

64.1 (4.07)^c

67.9 (4.94)^c

85.5 (6.72)^b

240.2 (19.0)^a

DON (μg N g⁻¹ soil)

10.69 (2.16)^b

19.85 (3.56)^a

21.9 (2.75)^a

22.1(2.70)^a

19.6 (3.52)^a

23.9 (2.63)^a

Available P (μg P g⁻¹ soil)

6.26 (0.09)^a

7.58 (0.04)^a

7.27 (0.13)^a

6.83 (0.09)^a

6.77 (0.09)^a

6.59 (0.10)^a

MBC (μg C g⁻¹ soil)

45.8 (5.47)^e

55.8 (2.06)^d

122.1 (6.09)^c

151.2 (5.49)^c

193.8 (8.21)^b

468.1(10.7)^a

MBN (μg N g⁻¹ soil)

8.91 (1.02)^b

9.30 (0.31)^b

10.6 (1.89)^b

16.6 (0.75)^b

21.5 (4.05)^b

31.9 (1.04)^a

Microbial biomass C:N

7.41 (1.32)^c

7.16(1.63)^c

10.28 (2.11)^b

9.72 (2.53)^b

9.90 (1.09)^b

13.3 (3.68)^a

pH

6.27 (0.05)^a

5.72 (0.12)^c

5.84 (0.11)^b

5.90 (0.16)^b

6.01(0.07)^b

6.08 (0.18)^ab

Root decomposition rate constant (k, year⁻¹)

0.53 (0.003)^c

0.56 (0.009)^b

0.61 (0.006)^a

0.64 (0.001)^a

0.63 (0.007)^a

0.56 (0.01)^b