水分和秸秆对石灰性土壤磷素形态转化影响的研究

EFFECTS OF FLOODING AND DRAINAGE ON THE MORPHOLOGICAL TRANSFORMATION OF PHOSPHATES IN LIMY SOILS

采用室内恒温培养试验，主要研究不同水分条件和加秸秆对石灰性土壤磷素形态转化的影响．结果指出，淹水促进石灰性土壤无机磷特别是外加磷向Ｆｅ－Ｐ和Ｏ－Ｐ转化，而拟旱则使土壤维持较高的Ｃａ２－Ｐ和Ｃａ８—Ｐ；淹水—回旱的土壤以Ｃａ２—Ｐ和Ｃａ８—Ｐ较高，但拟导—淹水的则以Ｆｅ—Ｐ和Ｏ—Ｐ较高；淹水后回旱比淹水更能使土壤拥有较多的Ｃａ２—Ｐ和Ｃａ８—Ｐ，而拟旱后淹水比拟旱有较高的Ａｌ—Ｐ、Ｆｅ—Ｐ和Ｏ—Ｐ．

The incubation at constant temperature(25±1)℃ was conducted to study the effects of flooding and drainage on the morphological transformation of phosphates in limy soils. The results indicated that: (a) flooding promoted phosphates, especially the applied phosphates transformation to Fe-P and O-P in limy soils, while drainage made the soils maintain higher Ca2-P and Cas-P levels; (b) Ca2-P and Ca8-P increased during the flooding-drainage cycle period and Fe-P and O-P increased during drainage-flooding cycle period; (c) pH and Eh of Huang soils decreased markedly by flooding, but those of red limeston soil did not.