小麦—玉米轮作长期肥料定位试验中土壤磷库的变化：Ⅱ.土壤Ols …

研究了冬小麦－夏玉米→春玉米轮作的长期肥料定位试验中，不同磷肥、有机肥用量下土壤Ｏｌｓｅｎ－Ｐ及各形态无机磷的动态变化。结果表明，土壤Ｏｌｅｓｎ－Ｐ及各形态无机磷含量增减决定于土壤磷素的积累与消耗量，长期不施磷肥，土壤Ｏｌｅｓｎ－Ｐ含量逐渐下降并趋向临界水平，磷肥用量与作物吸磷量基本持平时，可以维持土壤Ｏｌｓｅｎ－Ｐ动态平衡。以用量高于作物的吸磷量时，土壤Ｏｌｓｅｎ－Ｐ及各形态无机磷均有不同程度的

Dynamics of soil P pool in a long-term fertilizing experiment of wheat-maize rotation. II. Dynamics of soil Olsen-P and inorganic P]

Studies on the dynamics of soil Olsen-P and different form inorganic P in the long-term fertilizing experiment of winter wheat-summer maize-->spring maize rotation showed that the contents of Olsen-P and inorganic P were changed by the accumulation and consumption of P in soil. In P0 treatments, Olsen-P decreased gradually, and then, trended to the critical level. When fertilizing amount was basically equal to the intake by crops, the balance of Olsen-P was dynamically maintained. The contents of Olsen-P and inorganic P were enhanced, when applied P was larger than the P intake by crops. The major contents of residual inorganic P were Ca2-P and Ca8-P, both accounting for 52.3% of total inorganic P in average, and Ca8-P accounting for 78.3%. Al-P and Fe-P accounted for 26.1%, and O-P and Ca10-P accounted for 20.4% of total inorganic P. The availability of fertilizer P was obviously increased by long-term applying fertilizer P together with manure, compared with applying fertilizer P alone.