Spatial Variability Characteristic and Influencing Factors of Soil Available Potassium in New Tobacco Plantation District in Huili County

Geostatistics combined with GIS were used to analyze the spatial variability characteristics of soil available potassium and its influencing factors in new tobacco plantation district in Huili county. The result showed that the content of the soil available potassium in the study area was in the medium spatial variability, and it had a wide range which included lack, medium and rich level. The content of the soil available potassium had weak spatial correlation and its spatial variability was mainly influenced by the random factors, but it had a wide spatially dependent range, up to 27 292 m, the content of the soil available potassium in the study area gradually decreased from north to south (Hengshan Village-Neidong Village-Nange Village) and the eutrophication risk probability steadily decreased. The soil pH, organic matters and clay particle content had significant or very significant influence on the content of the soil available potassium, while the soil types and topographic conditions had no apparent influence on that.