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美国东南部低沿海平原造林地上加施磷肥,一直表明具有明显的效应。这些发现,近来使磷肥在许多排水不良的沿海平原造林地上得到了普遍应用。现在,该地区每年营造15万英亩以上的火炬松和湿地松林,都施用了磷肥,或与氮肥配合施用。所以磷肥的种类、含磷率,有效期及施用方法都存在着较大的差异。而这些因素都能影响磷肥效应的周期和效应的大小,但磷肥的种类和土壤性能似乎是关键因素。对酸性适中、含磷量中等的土壤,
Adding phosphate to afforestation on the low coastal plain in the southeastern United States has been shown to have significant effects. These findings have recently led to the widespread application of phosphate fertilizer in many well-drained coastal plains. Each year more than 150,000 acres of Pinus taeda and Pinus elliottii are now planted in the area, either with or without phosphate fertilizer. Therefore, the type of phosphate fertilizer, phosphorus rate, duration and methods of application there is a big difference. All these factors can affect the period and effect of phosphate fertilizer effect. However, the type of phosphate fertilizer and soil properties appear to be the key factors. Moderately acidic, medium phosphorus content of the soil,