干湿交替过程中石灰性土壤无机磷的转化及有效性

TRANSFORMATION AND AVAILABILITY OF INORGANIC PHOSPHORUS IN CALCAREOUS SOILS DURING FLOODING AND DRAINING ALTERNATING PROCESS

盆栽试验和培养试验结果表明：淹水能显著提高石灰性土壤速效磷含量，其作用顺序为，两合土＞淤土；淹水促使土壤无机磷组分中Ca2-P、Ca8-P含量增加，说明石灰性土壤淹水后土壤磷有效性的提高主要是Ca－P体系的活性提高所致。回旱后，土壤速效磷值明显降低，土壤无机磷组分中，Ca2-P、Al-P、Fe－P组分均呈降低趋势，土壤无机磷向难溶态转化。淹水降低了外加磷肥的肥效。

Pot and incubation experiments were carried out to study the effect of alternate flooding and drying on the transformation and availability of phosphorus in calcareous soils. The results indicated that flooding significantly increased P availability in calcareous soil and enhanced the transformation of inorgenic phosphate into more available fractions such as Ca2-P and Fe-P. After draining and drying the process reversed in the soils.