To explore excess P in the em bankm entupland ofthe south C hina,the alluvialsoilin Liuyang ofH unan province w as used fora field experim entto discuss the effectofreducing P fertilization on m aize yield,the utilization ratio ofP fertilizerand the runoffloss ofP.The results show ed that P fertilizer fluctuating w ithin 20% of the conventional w ould not influence m aize yield significantly, w hen fertilizer reduced to 30% ,the yield ofm aize reduced,how everthe difference w asnotsignificant.To som e extent,the reduction ofP fertilizercould not only im prove P fertilizer utilization by 0.13% ...