硫酸铝改良剂对苏打盐碱土磷素形态的影响

通过室内模拟盆栽改良试验，研究了硫酸铝的改良效果及施用后对土壤中磷素营养状况的影响。硫酸铝配施磷肥和氮肥对小麦的出苗和生长起着明显的促进作用。在硫酸铝及氮肥用量一定的条件下，随磷肥用量的增加，小麦的出苗和生长没有明显变化。无论施磷与否，土壤有效磷曲线均随硫酸铝用量的增加而呈下降趋势。改良剂用量不变，随磷肥用量的增加，土壤有效磷含量也在不断增加。无机磷分级及相关分析结果表明，施加不同用量的硫酸铝后，在不施用磷肥的条件下，各级无机磷平均含量的大小顺序为O—P〉Ca10—P〉Al-P〉Fe—P〉Ca2—P〉Ca8-P，其中Ca8-P是Ca2-P的有效补充；在施用磷肥的条件下，其变化顺序为Ca2-P〉Ca8-P〉Al-P〉O-P〉Fe—P〉Ca10-P，其中Ca8-P和O-P是Ca2-P的有效补充；在硫酸铝为0．3％，施用不同用量磷肥条件下，其顺序为Ca2-P〉Ca8-P〉Al-P〉Fe—P〉O-P〉Ca10-P，其中Ca8-P、Al-P和Fe—P成为Ca2—P的有效补充。

Effect of Aluminum Sulfate on Forms of Phosphorus in Soda Saline-alkali Soil

Soil indoors model experiments were carried out to study effects of aluminum sulfate(Al_2(SO_4)_3) on improved effectiveness and forms of phosphorus.The results showed that different Al_2(SO_4)_3 amounts and the same amounts of phosphate fertilizer and nitrogen fertilizer could obviously promote emergence rate and growth of wheat.If amounts of Al_2(SO_4)_3 and nitrogen fertilizer were given,applying different amounts of phosphate fertilizer,emergence rate and growth of wheat didn't change significantly.Whether phosphate fertilizer application or not,curves of available phosphorus were all decreased with increment of Al_2(SO_4)_3.If amounts of Al_2(SO_4)_3 were given,available phosphorus contents were increased with increment of phosphate fertilizer.Fractions of inorganic phosphorus in original soil and improved soils were studied.The results showed that the sequences of components of inorganic phosphorus were followed O-P>Ca_(10)-P>Al-P>Fe-P>Ca_2-P>Ca_8-P.The application of phosphate fertilizer made the components of inorganic phosphorus changed greatly.The changeable sequences of inorganic phosphorus content of soils improved by different Al_2(SO_4)_3 amounts were followed Ca_2-P>Ca_8-P>Al-P>O-P>Fe-P>Ca_(10)-P.Under different Al_2(SO_4)_3 amounts condition,Ca_8-P and O-P were the valid complement of Ca_2-P;under different phosphate fertilizer amounts condition,Ca_8-P,Al-P and Fe-P became the valid complement of Ca_2-P.