长期施肥下黄壤无机磷组分空间分布特征

The Characteristic of Spatial Distribution on Inorganic Phosphorus Fractions Accumulation and Migration in Yellow Soil under Long-term Fertilization

利用土壤无机磷分级方法，研究长期施肥对黄壤中不同组分磷累积、迁移的影响。结果表明，施肥土壤全磷、有效磷、无机磷的含量均较不施肥处理有明显增加，随土层深度的加深而显著减少，施肥主要增加了Ca2-P、Ca8-P、Fe-P、A1-P含量，而对Call3-P、0-P含量影响较小。Ca2-P、Ca8-P、Fe-P、Al-P、Calcl-P、0-P以表聚为主，同一土层上表现为0-P>Fe-P>Al-PJai。-P>Ca2-P>Cas-P。不同形态的无机磷含量随土层深度呈现垂直分布规律，在0.100cm土层中无机磷形态以〇-P、Fe-P为主，且该比例随土层深度的增加而增加。因此，从长远来看，有机无机配施促使无机磷组分在土壤剖面的移动得以放缓，还不足以影响到地下水质量，更有利于黄壤区农业的可持续发展。

The objective of this study was to explore the accumulation and migration of soil available phosphorus,total phosphorus and inorganic phosphorus using different fertilizer. The data were collected in twenty years longterm fertilization experiment in upland yellow soil of Guizhou Province. Analytical methods was based on soil inorganic phosphorus fractions. Results indicated that compared with the control treatments( unfertilized),soil available phosphorus,total phosphorus and inorganic phosphorus fractions in M( organic fertilization),NPK( nitrogen phosphorus and potassium fertilization) and NPKM( organic and inorganic fertilizers mixed) treatment were all increased significantly. The highest concentration of available phosphorus,total phosphorus and inorganic phosphorus were obtained in the topsoil,and decreased gradually with the increase of soil depth. Fertilization mainly increased the concentration of Ca_2-P,Ca_8-P,Fe-P and Al-P,while the changes of Ca_(10)-P,O-P were slightly. The order of concentrations was O-P > Fe-P > Al-P、Ca_(10)-P > Ca_2-P > Ca_8-P. The concentrations of Ca_2-P was the lowest but with the highest nutrient availability while the concentrations of O-P was highest with the lowest nutrient availability. The regularities of distribution in inorganic phosphorus were vertical distribution and surface gathering. The main concentrations of inorganic phosphorus were O-P,Fe-P in 0- 100 cm soil,and the proportion increased with depth of soil. Therefore,organic and inorganic fertilizers combine for application decrease the transportation of norganic phosphorus contents in vertical direction,and not affect the groundwater quality,which could benefit to the sustainableagricultural development of yellow soil areas in the long term.