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试验表明,在红壤和石灰性潮土上,一次大量施磷的总产量(红壤为6季,潮土为3季),在总施磷量相等的情况下,都高于或至少等于分次施磷。但其增产作用主要表现在前1-2季作物上。随着时间的延长,一次施磷的产量逐渐下降直至低于分次施磷,说明了随土壤和磷肥作用时间的延长,积累态磷的有效性逐渐下降,积累态磷的有效性不仅决定于与土壤接触的时间,以及土壤磷素吸附位的饱和度,还与作物类型有密切关系,如试验中的萝卜菜,利用积累态磷的能力甚高。从实用方面看,一次大量施磷最好不超过两季磷的总用量,只有在土壤磷素水平较高时,可以适当超过两季。
The results showed that the total output of a large amount of phosphorus application in red soil and calcareous alluvial soil (six seasons in red soil and three seasons in alluvial soil) were all higher or at least equal to the total amount of phosphorus application Apply phosphorus. However, its increase in production is mainly reflected in the first 1-2 seasons crops. With the extension of time, the yield of phosphorus decreased gradually until the phosphorus level was lower than that of the graded phosphorus, indicating that the effectiveness of accumulative phosphorus decreased gradually with the prolongation of soil and phosphate fertilization time. The availability of accumulated phosphorus was not only determined by The time of contact with soil and the saturation of soil P adsorption sites are also closely related to the crop type. For example, the radish in the experiment has a very high ability to utilize accumulated phosphorus. From a practical point of view, a large number of phosphorus is best not to exceed the total amount of two quarter of phosphorus, only in the high level of soil phosphorus, you can more than two seasons.