长期耕作施肥对白浆土磷组分及其有效性的影响

Effects of Long-term Culture and Fertilization on the Contents of Forms of Phosphorus and Their Availability in Albic Soil

采用顾益初等无机磷和Bowman Cole有机磷分级体系 ,对长期施肥和耕作的白浆土中无机和有机磷组分及其与土壤有效磷的关系进行了研究。结果表明 ,白浆土耕层全磷含量为 4 6 1.6 0mg kg ,其中无机磷占土壤全磷 5 8.0 8% ,其余为有机磷。无机磷和有机磷各组分含量高低顺序分别为O P >Fe P >Al P >Ca1 0 P >Ca2 P >Ca8 P和MLOP >MROP >HROP >LOP ;长期施用有机肥可以增加土壤Fe P、Al P、Ca2 P及有机磷各组分的含量 ;施化肥对土壤有机磷影响不大 ,但对提高土壤O P、Fe P和Al P的含量有一定效果 ;长期秸秆还田使Fe P、Al P、MROP和HROP增加 ,而长期不施肥除HROP变化不大外 ,其余各组分无机和有机磷都处于消耗状态 ;免耕比普翻和深松更利于土壤Ca2 P、Ca1 0 P、O P、MROP和HROP的积累 ;相关和通径分析表明 ,土壤有效磷与Fe P、Al P、LOP和MLOP之间呈显著正相关 ;Ca2 P、Fe P、Al P、LOP、MROP和MLOP对土壤有效磷均有一定的正效应。

The method of Gu Yichu et al. and Bowman and Cole(1978) was applied to study the effects of long-term culture and fertilization on the contents of the forms of inorganic and organic phosphorus and their relationship with soil available P in albic soil. The results showed that the total phosphorus content was 461.60 mg/kg, among them the inorganic phosphorus accounted for 58.08% and the other was organic phosphorus in albic soil. The orders of the contents in the various inorganic and organic P forms were O-P>Fe-P>Al-P>Ca 10 -P>Ca 2-P>Ca 8-P and MLOP>MROP>HROP>LOP, respectively. Long-term application of organic fertilizer could keep high level of available P and increase the contents of Fe-P, Al-P, Ca 2-P and various organic P forms, and application of inorganic fertilizer affected very little on the various organic P forms but increased the contents of O-P, Fe-P and Al-P. The contents of Fe-P, Al-P, MROP and HROP were increased by long-term mulching straw, but all inorganic and organic P forms except HROP decreased in long-term no fertilization. No-tillage management was more beneficial to accumulation of Ca 2-P, Ca 10 -P, O-P, MROP and HROP than conventional tillage and subsoiling. The results of correlation and path analysis showed that available P significantly correlated to Ca 2-P, Fe-P, Al-P, LOP and MLOP, and there was a positive effect of Ca 2-P, Fe-P, Al-P, LOP, MROP and MLOP on the available P.