华北桓台县土壤养分的时空变化格局

Spatio-temporal Variability of Soil Nutrient in Huantai County in North China

为了实现精确施肥和防治土壤肥力退化,通过监测土壤养分的时空变异了解土壤耕作管理及污染等过程对土壤肥力的影响,采用GIS和地统计学相结合的方法对华北桓台县1989年和2006年的土壤碱解氮、速效磷和速效钾的空间分布进行分析。结果表明,与1989年相比,2006年土壤碱解氮含量普遍提高,中等水平以上(>91mg/kg)的面积占整个研究区面积的21.23%,含量61～90mg/kg的土壤面积增加了7.05%,低含量(<60mg/kg)的面积减少了8.07%。土壤速效磷也大幅度增加,主要是零散的较低级别含量的斑块向高级别转化,丰富级别(>21mg/kg)的面积增加了26.92%,含量缺的(<15mg/kg)地块面积比重下降了52.75%;土壤速效钾含量整体提高,2006年平均含量达118mg/kg,变化最明显的是101～150mg/kg级别,增幅达25.18%。桓台县各土壤养分含量均有显著提高。此研究结果对于桓台县农业可持续发展,制定优化的高效施肥措施和方案有一定指导意义。

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% 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 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 rapidly-available potassium （101 mg/kg and 150 mg/kg） increased by 25.18%. The soil nutrient contents wereall 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.