基于几种土壤测试方法的华南菜田磷素丰缺指标研究

依托2002—2009年开展的蔬菜田间试验结果，土样分别用Olsen法、Mehlich 1法、Mehlich 3法和ASI法测定其有效磷含量，建立上述测试方法的菜田土壤磷素丰缺指标，并进行不同测试方法的相关研究。以蔬菜产量＜75%、75%～90%、90%～95%和＞95%为标准，将菜田土壤有效磷分为“低”、“中”、“高”和“极高”4个肥力等级; 对应的土壤有效磷丰缺指标Olsen-P为＜23、23～59、59～81和＞81 mg/kg; M1-P为＜19、19～102、102～179和＞179 mg/kg; M3-P为＜19、19～96、96～165和＞165 mg/kg; ASI-P为＜22、22～68、68～98和＞98 mg/kg。Olsen法、M3法、M1法和ASI法4种方法，两两的相关性均达到极显著水平。

Abundance and deficiency indices of phosphorus in South China vegetable field based on different soil testing methods

Based on the results of field experiments on vegetable conducted during the year 2002-2009, the abundance and deficiency indices of soil available phosphorus was investigated. The different soakage methods of soil available phosphorus were also discussed. Soil available phosphorus were classified into four classes (low, medium, high, and extremely high) corresponding to the percentage of maximum vegetable yield (＜75%, 75%-90%, 90%-95% and ＞90% relative yield). The abundance and deficiency indices were simulated by the logarithm models. The results indicates that available phosphorus indices for different soakage methods are Olsen-P ＜23, 23-59, 59-81 and ＞81 mg/kg; Mehlich1-P ＜19, 19-102, 102-179 and＞179 mg/kg; Mehlich3-P ＜19, 19-96, 96-165 and ＞165 mg/kg; ASI-P ＜22, 22-68, 68-98 and ＞98 mg/L, corresponding to different class of soil available phosphorus. There were significant correlation between the results obtained from Olsen, Mehlich 3, Mechlich 1 and ASI methods.