农业系统中磷肥残效及磷循环研究Ⅰ.作物吸磷量、磷肥残效及土壤有效磷变化

Residual effect of phosphorus fertilizer and phosphorus recycling in a farming system Ⅰ. Phosphorus uptake by crops, residual effect of phosphorus fertilizer and changes of soil available phosphorus.

在碳酸盐褐色土上的6年试验表明,总施肥量相同情况下,6年一次大剂量和每年小剂量两种施磷方式的作物增产效果相似而以后者略高,但后者在提高土壤有效磷方面明显优于前者。在碳酸盐褐色土上一次施磷的残效至少可持续5年以上,虽然大剂量施磷第1年的利用率仅为7％,但6年累加利用率可达34％。土壤中残留肥料磷进入速效库的比例以每年小剂量处理较高,施肥第6年该比例为17％;一次大剂量施肥后6年只有2％的残留肥料磷进入速效库。

The results from a six years field experiment conducted on a calsic cinnamon soil indicated that there was no significant difference between the crop yields from two different ways of applying phosphorus fertilizer——once every six years with high rate and once every year with low rate, the latter gave a little more yields than the former, but was more effective in establishing soil available phosphorus pool. The residual effect from one application of phosphorus seemed to last more than five years on the calsic cinnamon soil, and thus, although the recovery of phosphorus was as low as 7% at the first year of application with high rate, the total recovery in six years was as high as 34%. The proportion of residual phosphorus transfering into soil available phosphorus pool was about 17% after six years of applying phosphorus every year with low rate, but only 2% from one application with high rate.