| When the soil water properties and soil water-storage was studied with traditional statistic method, samples were entirely independent and obeyed normal distribution, not taking into account spatial relative of sampling location. But most of soil properties are not entirely independent; some even have spatial correlation in some extension. Therefore, if the soil water properties and soil water-storage was studied with traditional statistic method, we would not know the variate are dependent or independent, whether the results have spatial distributing pattern or not, even not know whether the number of sample is economical and rational or not. Geo-statistics is the most available method to study spatial variability and spatial distribution of soil properties. Previous studies were concentrated on spatial variability of soil properties and soil water-storage in flat, ignoring how terrain affects soil properties. The results from research on the spatial-temporal variability of soil water content, spatial variability of soil water content of different layers and soil water-storage in sloping field can be showed.1. The most of soil water properties obey normal distribution. If it would not obey normal distribution, it may be transitioned with log.2. Soil water contents have moderate and high spatial correlation in upland. The changing trend of the range with season is not apparent, but the ranges change from 3.02m to 39.29m. The sills change from 0.83 to 4.98, which represent apparently changing trend with season. The nuggets change with season apparently from 0.13 to 4.98. The nugget and sill have similar changing trend. During the observed period, soil water contents in different layer changed with season apparently and similarly, which can be concluded that weather is the most important effect on change of soil water content. The nuggets, sills and ranges do not change with the depth of soil profile apparent. But the sill correlated with nugget significantly.3. Most of soil properties are moderate and high spatial correlation in hillslope. Bulk density is increased with the depth of soil profile; field capacity and saturation are reverse. Water content and wilting point fluctuate with the profile. The coefficient of variation of soil water content fluctuates from 3.04% to 26.98% with depth of profile. The coefficient of variation of saturated water content decreased with the depth of profile. The coefficient of variation of bulk density and field capacity fluctuate with depth of soil. In conclusion, the variable degree of the soil water properties and bulk density in different layers is water content>wilting point>field capacity>saturation>bulk density. The nuggets of soil properties have different changing rule with depth of profile. Saturation and capacity change with depth similarly. The nuggets of bulk density and wilting point are very tow, and the nugget of soil water content is decreased with depth. The range of bulk density is decreased with depth, and the range of soil water properties fluctuate with depth. Bulk density in 0~20cm, 20-40cm and field capacity in 20~40cm can be simulated with pure nugget effect model , and they are not spatially correlated in sampling scope.4. In the hillslope, D(θ), c(θ) and K(θ) of soil water have high spatial correlation. D(θ), C(θ) and K(θ) are significant affected by Soil water content, capillary pore and sand content Bulk density and non-capillary pore aperture are significantly affected on permeability rate. Correlation analysis indicates that it is significant correlate. Nugget/sill of D(θ), C(θ) and K(θ)are 0.306%, 0.0407% and 5.11 %. The sill of permeability rate achieved 100% so that it was not spatial correlated. The ranges of different hydropower properties are from 31.4 to 270.6m. Sampling interval should be determined by concretely situation. The changing trend of D(θ), C(θ) and K(θ) are similar in hillslope, and the peak value is in the middle part of the study area. All of the soil hydropower properties have... |
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