施用豆科绿肥对砖红壤有效磷含量的影响

土壤缺磷是热带和亚热带地区作物生产的主要限制因子之一。本研究分析了14份热带、亚热带豆科绿肥施入土壤后对砖红壤有效磷含量影响的时间动态变化。结果表明，施用绿肥后不同时段能不同程度地提高土壤有效磷的含量，且施用绿肥后的土壤有效磷含量显著高于不施用绿肥土壤，其中木蓝（Magnolia lotungensis）对砖红壤有效磷含量增量变幅高达339%。此外，施用不同的绿肥对土壤有效磷含量的影响不同，但对土壤有效磷含量影响的基本规律一致。施用绿肥时砖红壤有效磷含量提高较大的最佳埋田时间为1个月。

Effects of application of the leguminous green manures on phosphorus content in latosol soil

Low available phosphorus in soil is one of the major limiting factors for crop production in the subtropical and tropical regions. A field experiment was conducted to determine the temporal changes of the phosphorus content in latosol soil when 14 tropical legumes were applied into soil in this study. The results of this study showed that the available phosphorus content of soil treated legumes green manures was higher than that of control, indicating that application of green manures to soil increased the available P content in soil to some extent, in which Magnolia lotungensis showed the highest effectiveness and increased available phosphorus content of soil by 339%. 14 tropical legumes showed a different effect on the available phosphorus content of soil as application time increased, but they shared a similar trend. This study suggested that the best time for application of leguminous green manure to latosol was the first month.