SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...

Chapter 3 Spatio-temporal variability of soil moisture in grazed steppe areas investigated by geostatistics
HG, suggesting that water regimes were changed by different grazing intensities.
SWC was always greater in UG 99 than in UG 79, which can be explained by the
larger leaf area of shrubs increasing rainfall interception and the thicker litter
layer reducing water infiltration in UG 79. Compared to the two plots grazed at
moderate intensity (WG and CG), SWC in UG 79 was greater after long dryness
but smaller under wet and medium conditions. This could be due to the
pronounced accumulation of organic matter observed, which would impede
evaporation under dry water status (Zhao et al., 2007) and inhibit water
infiltration under medium and wet water statuses, as indicated by the WDPT
(Table 1). The smallest SWC was always observed in HG where scarce vegetal
cover could have increased water evaporation.
Table 3.2. Descriptive statistics of soil moisture for three moisture conditions measured during
2004-2006
Treatment Sampling soil water statuses Min. Max. Mean CV Skewness Kurtosis
UG 79 20% (Wet) 21 28 24 5 0.50 -0. 05
UG 99 20% (Wet) 25 30 27 4 -0.38 0. 33
WG 20% (Wet) 23 27 25 3 -0.38 -0. 35
CG 20% (Wet) 22 28 25 5 0.50 0. 15
HG 20% (Wet) 17 26 21 9 -0.21 0. 31
Min.: Minimum (%); Max.: Maximum (%); CV: Coefficient of variation (%).
There was a weak to moderate spatial dependency of soil water content
varying from 13 to 75% (Table 3), according to the classification of spatial
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