Abstract:

In order to realize precision fertilization and prevent soil fertility degradation, the author studied the effects of farming management and excessive fertilisation by means of monitoring soil nutrients variation in space and time. The method of combination of geographic information system (GIS) and geostatistics was conducted to investigate the space distribution of alkali-hydrolyzable nitrogen, rapidly-available phosphorus and potassium in 1989 and 2006 in Huantai County, north China. The results suggested that the contents of alkali-hydrolyzable nitrogen in soil were generally increased compared with that in 1989, the area over the middle level (>91 mg/kg) occupied 21.23% percent of the whole research area, the area with alkali-hydrolyzable nitrogen contents between 61 mg/kg and 90 mg/kg increased by 7.05%, while the area with low content (<60 mg/kg) decreased by 8.07%. The contents of rapidly-available phosphorus were also significantly increased, which was mainly resulted from transformation from lower to higher level. This conversion had two traits as follows: the area of rapidly-available phosphorus in high concentration(>21 mg/kg) increased by 26.92%, and that in low concentrations was decreased by 52.75%. Additionally, the contents of rapidly-available potassium in soil had been general improved and the average contents were 118 mg/kg in 2006. Especially the contents of rapidly-available potassium (101 mg/kg and 150 mg/kg) increased by 25.18%. The soil nutrient contents were all increased significantly. In conclusion, the present study provided guidance on making decision of high efficiency fertilizer utilization and might be beneficial for sustaining agricultural development in Huantai County.