长期施肥对红壤性水稻土有机磷组分的影响

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

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 47mg·kg-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 80mg·kg-1,占有机磷总量的51 58%;中度稳定性有机磷(92 46mg·kg-1)占35 38%;高度稳定性有机磷(20 35mg·kg-1)占7 79%;活性有机磷含量最低(13 67mg·kg-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CK>NK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+OM>P>NPK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)。

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)