Table 2 Soil organic carbon (SOC), inorganic carbon (SIC) stocks and the SIC:SOC ratio in typical croplands of North China.

From: Dynamics of soil organic and inorganic carbon in the cropland of upper Yellow River Delta, China

Region

The annual precipitation (mm)

Soil types

pH

SOC stock (kg C m−2)

SIC stock (kg C m−2)

The SIC/SOC ratio

Reference

0–30 cm

30–100 cm

0–30 cm

30–100 cm

0–30 cm

0–100 cm

Yanqi (n = 9)

80

Brown Desert Soil

8.2

4.53 ± 0.52

4.38 ± 1.69

11.07 ± 1.45

31.3 ± 7.42

2.44

4.72

Wang et al.15

Urumqi (n = 5)*

299

Gray Desert Soil

8.1

4.25 ± 1.49

4.90 ± 0.65

2.03 ± 0.31

3.38 ± 0.77

0.48

0.59

Wang et al.8

Lanzhou (n = 33)

300

Loess Soil

8.9

2.46 ± 0.74

3.64 ± 1.44

6.24 ± 0.99

14.54 ± 2.39

2.54

3.41

Zhang et al.22

Yangling (n = 5)*

585

Manural Loess Soil

8.6

4.16 ± 0.93

5.18 ± 0.26

3.94 ± 0.27

5.06 ± 0.19

0.95

0.96

Wang et al.8

Zhengzhou (n = 5)*

641

Fluvo-aquic Soil

8.3

3.29 ± 0.59

3.31 ± 0.28

2.95 ± 0.08

5.19 ± 0.39

0.9

1.27

Wang et al.8

Zibo-Binzhou (n = 31)

600

Fluvo-aquic Soil

8.2

2.70 ± 0.64

3.03 ± 0.64

4.06 ± 0.81

12.83 ± 2.80

1.50

2.95

This study

  1. *Each site collected in 2002 and 2009 with three replicates.