Spatial Distribution of Soil pH Values in Urban Area of Xuzhou City

Variation of soil pH value which reflected soil quality was investigated based on a soil survey involving soil sampling and analysis in urban area of Xuzhou during the period from Sept.25 to Oct.5,2010.Geo-statistics incorporated with GIS spatial technology was applied to analysis of the spatial variability of pH values ranging from 6.47 to 8.48 over the study area.The results showed that soil pH dataset was basically congruent with the normal distribution,and the semi variogram could be best depicted by the spherical model with nugget/still ratio of 21% and the spatial heterogeneity of 9 500 m.In general,soil pH spatial distribution was characterized by an outward trend of low-high-low from the central part of the city,implying the influences of human activities though still less than the natural ones.