渗灌灌水控制下限对保护地土壤剖面磷素分布的影响

    Effect of control lower limit of subsurface irrigation on phosphorus distribution in soil profiles of protected land

    • 摘要: 连续5 a以相同方案于2000~2004年在沈阳农业大学科研基地进行保护地番茄栽培的渗灌试验,其5个处理的灌水控制下限土壤水分吸力值分别为10、16、25、40和63 kPa,灌水控制上限土壤水分吸力值均为6 kPa。 研究结果表明:渗灌及其灌水控制下限能够显著影响不同形态磷素含量在土壤剖面中的分布。具体表现为土壤表层(0~10 cm和 10~20 cm)的土壤全磷、无机磷和速效磷含量均高于其他土层,在30~40 cm土层的含量为最低,灌水对土壤速效磷含量的影响主要发生在0~30 cm土层;有机磷随着灌水向土壤底层发生迁移,其含量在土壤深层40~60 cm为最高;各处理不同深度土层中的磷素均以无机磷为主。因此,灌水可以作为调节土壤中磷素的转化及其有效性的方式。

       

      Abstract: A subsurface irrigation experiment was conducted in a five-year tomato-grown protected land in the bases for scientific research of Shenyang agricultural university during 2000-2004. To different treatments, the irrigation allowable lower limits were set to 10, 16, 40, and 63 kPa, respectively, but the irrigation allowable upper limits of them were set to be 6 kPa. Results showed that the distribution and contents of phosphorus in soil profile were affected significantly by subsurface irrigation and irrigation lower limit. Soil total phosphorus, inorganic phosphorus and available phosphorus were higher at the depth of 0-10 and 10-20 cm than those at other depths, and were lowest at the depth of 30-40 cm. Changes of available phosphorus was mainly at the depth of 0-30 cm. Soil organic phosphorus leached down into the soil layers with irrigation water, and reached the highest contents at the depth of 40-60 cm. Soil inorganic phosphorus was the dominant form of phosphorus in different soil layers for all treatments. The results indicated that irrigation could be applied to facilitate the transformation and availability of phosphorus in soil.

       

    /

    返回文章
    返回