常规浸提剂与联合浸提剂测定我国北方石灰性土壤有效磷钾的比较

Comparison Between General Extracting Agent and Combined Extracting Agent in Determining Available-P and Available-K Contents in Calcareous Soil

使用常规浸提剂与两种联合浸提剂Mehlich 3(M3)、ASI分别测定了中国8个地区10种土壤样品的有效磷、速效钾含量,分析比较了常规浸提剂与两种联合浸提剂测定土壤有效磷速效钾的差异性及相关性。统计分析表明,对于有效磷,M3、ASI两种联合浸提剂的浸提结果均大于常规浸提剂的浸提结果,且M3浸提剂浸提结果的变幅较常规浸提剂浸提结果相对较小,而精确度较高。相关分析表明,常规浸提结果与M3浸提结果呈极显著正相关(P<0.01),相关系数为0.680。对于速效钾,M3浸提剂的浸提量较常规浸提剂相近,常规浸提量与M3浸提量呈极显著正相关(P<0.01),相关系数为0.996。综合而言,M3这种联合浸提剂是测定土壤有效磷、速效钾的理想浸提方法。

Soil available-P and available-K contents were measured and compared by two combined extracting agents and general extracting agent for 10 soil samples collected from different regions of China. The results showed that available-P determined by two combined extracting agents of M3 and ASI are greater than that by general extracting agent, and M3 method has a smaller variation but a higher accuracy. Significant correlation was found between M3 method and general method（P〈0.01） with a correlation coefficient of 0.680. Available-K contents determined by M3 method was similar to that by general method, and significant correlation was existed between the two methods（P〈0.01） with a correlation coefficient of 0.996. In a word, M3 combined extracting agent is an ideal digestion method in measuring soil available-P and available-K for calcareous soil.