Abstract: Along with the development of research on soil spatial variation and precision agricultural practice, scale effect of soil nutrition performs obviously, which is promoted bottleneck in research and practicce on accurate agriculture. In this research, it is sampled by nested scenario in Houhu farm in Jianghan Plain; the variation of soil total nitrogen (TN) is simulated by using geostatistics in scale of 400, 100 and 50 meters separately; effect of scale on TN variation is analyzed; the simulating method under multi-scale data is put forward; and the spatial distribution of TN is described in this region. The research result shows that, data in three scale(400m, 100m, 50m) are all agree with normal distribution; spherical model fit best for semi-variogram; in different scale, TN varies under different driving factors, which leads to the appearance of scale effect; the estimation, through multi-scale simulation, is more accurate than traditional method, which isn’t limited by nested distance(100m, 50m in this research); furthermore, the standard error is only 1/3-1/2 of the original method in local area; the degree that the precision improved relates to the concert of scale distance. The simulation of soil nutrition by nested kriging method, is more reliable and concrete, which can offer scientific basis for formulation and implementation of the precision agricultural scheme in Jianghan Plain in China

Key words: spatial variation, scale effect, nested simulating method