| 1. | The amounts of ca2 - p , al - p , labile po and mid - labile po , which are more available for plant , increased with the improvement of soil fertility , but generally the avail . p was very poor in soils . 2 随着肥力水平的提高,对作物有效性较高的ca _ 2 - p 、 al - p 、活性op和中度活性op等的含量都呈上升趋势,但是土壤中有效磷含量整体偏低。 |