| Total 364 top-layer (0-20cm) soil samples were taken in 70 m grid (cropping fields), 50 m grid (fruit orchard), and 30m (greenhouse vegetable) from 219 ha cultivated land in Xinji village of Shaanxi Province for investigation spatial variability of soil pH, OM, and nutrients (available N, P, K, Ga, Mg, S). Results indicated that soil N was widely deficient in the study area, and 11.5% of all samples was K deficient on the basis of assessment standard of SAI, correspond values were 98.9% for N. Soil K deficient was mainly distributed at no-irrigated fields. The range of spatial correlation was determined from semivariance analysis of the data and was found to vary among nutrients. K had the shortest correlation range (592m) and OM, S had the longest (1865-1853m), whereas Mg, P, and Ca had intermediate spatial correlation ranges. It was found the spatial heterogeneity of K was small and OM, P, Ca, Mg, S was intermediate. Spatial variability of soil nutrients could be contributed to unbalance fertilization in this area. Based on the present situation and spatial distribution characteristics of soil nutrients, the key elements in nutrient management are K and P in the study village.
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