SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...

Chapter 2 Spatial variability of soil properties affected by grazing intensity in Inner Mongolia grassland
Table 2.7. Descriptive statistics of different parameters in UG 79 in 2005.
Parameters Min. Max. Mean SD CV Skewness Kurtosis
Ln(K) 2.27 4.36 3.15 0.49 15.56 0.30 -0.43
Ln(WDPT) 0.69 5.89 2.42 1.25 51.65 0.83 0.16
SS 36.34 64.87 52.55 6.73 12.81 -0.42 -0.33
SWC 0.02 0.08 0.04 0.01 25.00 1.33 0.94
Sand 41.00 56.70 48.50 3.42 7.05 -0.14 -0.7
Silt 28.80 42.10 35.30 2.61 7.39 0.24 0.18
SOC 18.40 45.10 31.20 5.70 18.27 0.27 -0.15
BD 0.66 1.15 0.94 0.10 10.64 -0.40 -0.02
K: hydraulic conductivity (cm d -1 ); WDPT: water drop penetration time (s); SS: shear
strength (kPa); SWC: soil water content (cm 3 cm -3 ); Sand: sand content (%); Silt: silt content
(%); SOC: soil organic carbon (g kg -1 ); BD: bulk density (g cm -3 ).
Table 2.8. Isotropic variogram parameters for different properties in UG 79 in 2005.
Parameters
Nugget
Co
Sill
Co+Cs
Range
A0 (m)
Proportion
Cs/(Co+Cs)
R 2 RSS γ-Model
Ln(K) 3.50E-02 2.70E-01 91 0.87 0.82 5.20E-03 Exponential
Ln(WDPT) 1.07E+00 2.54E+00 311 0.58 0.87 9.47E-02 Spherical
SS 6.03E+00 4.64E+01 43 0.87 0.78 6.67E+01 Exponential
SWC 9.00E-05 2.50E-04 142 0.62 0.96 7.20E-10 Spherical
Sand 1.00E-02 1.43E+01 94 1.00 0.96 1.90E+01 Spherical
Silt 1.00E-02 7.99E+00 86 1.00 0.95 6.15E+00 Spherical
SOC 1.89E+01 3.89E+01 191 0.52 0.94 1.01E+01 Exponential
BD 1.40E-03 1.00E-02 57 0.87 0.67 3.90E-06 Exponential
K: hydraulic conductivity (cm d -1 ); WDPT: water drop penetration time (s); SS: shear
strength (kPa); SWC: soil water content (cm 3 cm -3 ); Sand: sand content (%); Silt: silt content
(%); SOC: soil organic carbon (g kg -1 ); BD: bulk density (g cm -3 ).
former studies (e. g. Qiu et al., 2001; Ferrero et al., 2005; Iqbal et al., 2005).
Each variogram was the basis for the mapping by a kriged interpolation scheme
of corresponding parameters. The ordinary kriged contour maps revealed
moderate positional similarity of different soil properties, with complex positional
effects in the plot’s interior (Fig. 3). The left part (close to fence, implied the
formation of islands of fertility around fence) showed lower values of K and BD,
but higher values of SWC, SOC and WDPT than that in the right part. Sand
content was high in the central part extending from the upper-right to nether-left
direction, but low at the two edges while a right opposite trend was observed for
25