北京市平谷区农田土壤养分评价与变化特征

2005年平谷区农田耕层土壤养分分析结果表明,全区耕层土壤有机质、全氮、速效磷和速效钾的平均含量分别为14.51g/kg、0.89g/kg、32.80mg/kg和136.79mg/kg,有机质和全氮含量总体处于中等水平,速效磷和速效钾含量总体处于高水平。在集中分布区,土壤有机质含量的次数分布曲线近似于呈偏正态分布,全氮近似于呈正态分布,速效磷和速效钾近似于呈偏态分布。各养分的变异程度由小到大依次为有机质、全氮、速效钾、速效磷。与1980年全国第二次土壤普查平谷区养分含量结果相比,全区农田土壤有机质含量增加了21.8%,全氮含量增加了17.1%,速效磷含量增加了246.0%,速效钾含量下降了8.1%。

Review and Change of Arable Soil Nutrients Content in Pinggu District of Beijing

The results of the research of arable soil nutrients in Pinggu District of Beijing in 2005 showed that the average content of organic matter,total nitrogen,available phosphorus and available potassium were 14.51 g/kg,0.89 g/kg,32.80 mg/kg and 136.79 mg/kg respectively. The content of organic matter and total nitrogen were medium level, while the available phosphorus and available potassium were high level. Within the range, frequency distribution of the content of soil organic matter appeared in deviated normal distribution, and total nitrogen appeared an approximate normal distribution, and the available phosphorus and available potassium appeared an approximate deviated distribution. The order of coefficient of variation(CV %) is organic matter