长期施肥对红壤性水稻土有机磷组分的影响

以19年肥料长期定位试验为背景,应用Bowman和Cole的有机磷分组方法,对红壤性水稻土有机磷组分及其变化进行了研究。结果表明:红壤性水稻土耕层有机磷含量较高,为225.93～322.47mgkg-1,占土壤全磷的28.59%～42.34%。土壤有机磷各组分中以中度活性有机磷含量最高,平均为134.80mgkg-1,占有机磷总量的51 58%;中度稳定性有机磷(92.46mgkg-1)占35.38%;高度稳定性有机磷(20.35mgkg-1)占7.79%;活性有机磷含量最低(13.67mgkg-1),占5.23%;长期施肥对土壤各组分有机磷量产生影响,耗磷处理,主要是中度活性有机磷和活性有机磷下降,降低量以CKNK处理。施磷主要促进中度稳定性有机磷和高度稳定性有机磷的增加,增加幅度以NPK+OMPNPK处理。不同施肥措施对土壤有机磷和无机磷库的耗竭或积累速度是不同的,耗磷条件,土壤有机磷/无机磷的比值上升,施磷使有机磷/无机磷比值下降.土壤供磷强度与有机磷/无机磷的比值呈显著负相关(r=-0.9497* ,r0.05=0.878)。

Effect of long-term fertilization on the forms of organic phosphorus in paddy soil derived from red earth

Based on the long term fertilization experiment (19 years) in paddy soil derived from red earth, the method of Bowman and Cole (1978) was applied to study the effect of long term fertilization on the forms and change of organic phosphorus in paddy soil The results showed that the organic phosphorus contents were 225.93 to 322.47 mg·kg^-1 in surface soil, accounting for 28.59% to 42.34% of the total P. In the various forms of organic P in paddy soil, MLOP was highest (13480 mgkg^-1), accounting for 51.58% of total organic P, followed by MROP (92.46 mg·kg^-1, 35.38%), HROP (20.35 mgkg^-1, 7.79%), and LOP (13.67 mg·kg^-1, 5.23%) In the treatment of no P application, it mainly caused the contents of MLOP and MROP to decrease, and the decreased amount was CK>NK. MROP and HROP contributed most to the increase of organic P with continual P application, and the order of the increase was NPK+OM>P>NPK The change rate of organic P was different from that of inorganic P under different fertilization treatments The ratio of organic P to inorganic P rose in the no P application, but declined in the continual P application The P supplying capacity was negatively correlated with the organic P/inorganic P ratio (r=-0.9497^* ,r_0.05=0.878)