Abstract: Taking Zhongfeng tea garden in low mountain and hilly region as an experiment site, Geostatistics and GIS were used to analyze the spatial variability of soil potassium, and also compared its spatial heterogeneity. Results showed that: (1) Under the mesoscale,available potassium and slowly available potassium coefficient of variation were 40.21% and 43.39%, belongs to the medium degree variation, and under the small scale, the coefficient of variation were 42.12% and 46.42%, also belongs to the medium degree variation. (2) Under the mesoscale, soil available potassium has the strong spatial relevance in 70° direction, but in 25°, 115° and 160°direction it has the medium degree relevance. Slowly available potassium has the medium spatial relevance in 113°direction, but in 68°, 158° and 203° direction it has the strong spatial relevance. Under the small scale, available potassium in 70° direction spatial variability was obviously, the variation is very small in other directions, slowly available potassium in 72° and 118° direction spatial variability was obvious. (3)Under the mesoscale, available potassium assumed the belt-shaped distribution in northwest to the southeast direction, and in the vertical direction with the altitude is extremely remarkable related, but slowly available potassium unobviously lelated in spatial distribution. Under the small scale, available potassium assumes the massive distribution, its whole tendency by northwest to eastwest direction increased, slow available potassium shows the same tendency as available potassium.

Key words: soil potassium, spatial variability, tea plantation soil, low mountain and hilly region