为明确干旱绿洲灌区春玉米磷肥投入阈值，于2011 — 2013年在甘肃省农业科学院张掖节水农业试验站进行了不同施磷量定位试验，研究施磷量对春玉米的产量、磷肥利用率以及养分平衡的影响。结果表明:在一定的施磷(P2O5 0～170.04 kg/hm2)范围内，春玉米产量随施磷量的增加而增加，在P2O5 170.04 kg/hm2时产量(14 337.33 kg/hm2)达到最高，较其他施磷处理分别增产56.87%、29.38%、20.61%、21.50%，较不施肥处理增产率达112.84%，此时磷肥利用率为23.80%，超过此值则籽粒产量略有降低。磷肥的产量效应与土壤有效磷含量高低有显著关系，施磷显著增加土壤耕层有效磷(Olsen-P)含量，较不施磷处理增加9.28%～925.27%。磷肥的投入量大于作物需磷量时，会加剧土壤磷残留量的增加，并对土壤水环境造成污染，适量施磷量(P2O5 85.02 kg/hm2)有利于土壤有效磷的平衡。当磷素投入阈值为每年施磷(P2O5)170.04 kg/hm2时，既保证土壤养分平衡，又减小对环境的影响。综合春玉米产量、磷肥利用率以及磷素平衡并结合试验区的肥力分析认为，在保证春玉米高产并减少环境污染的前提下，干旱绿洲灌区春玉米区磷肥投入阈值应为P2O5 85.02～170.04 kg/hm2。

In order to clarify the input threshold of phosphate fertilizer of spring corn in the arid oasis irrigation area，a positioning tests of different phosphorus application amount positioning tests was studied on the yield，use efficiency of phosphate fertilizer and nutrient balance of spring corn in Zhangye Water-saving Agricultural Experimental Station of Gansu Academy of Agricultural Sciences from 2011 to 2013. The results showed that within the range of P2O5 0 ~ 170.04 kg/hm2, the yield of spring corn increased with the increase of phosphorus application. When P2O5 was 170.04 kg/hm2, the yield (14 337.33 kg/hm2) reached the highest, which increased by 56.87%, 29.38%, 20.61% and 21.50%, respectively, compared with other phosphorus treatment, and the yield increased by 112.84% compared with no fertilizer treatment. At this time, the phosphorus fertilizer utilization rate was 23.80%, and the grain yield decreased slightly when the phosphorus fertilizer utilization rate exceeded this value. The yield effect of phosphorus fertilizer was significantly related to the content of available P in soil. The application of phosphorus significantly increased the content of olsen-P in the topsoil, which was 9.28%~925.27% higher than that the no-phosphorous treatment. When the Amount of phosphorus fertilizer input is larger than the amount of phosphorus required by crops, it will aggravate the increase of soil phosphorus residue and pollute the soil water environment. The appropriate amount of P applied(P2O5 85.02 kg/hm2) is conducive to the balance of soil available P. When the phosphorus(P2O5) input threshold is 170.04 kg/hm2 per year, the soil nutrient balance is guaranteed and the impact on the environment is reduced. Compositing spring corn yield, phosphorus fertilizer utilization rate and phosphorus balance, and combining with the fertility analysis of the experimental area, it was concluded that the threshold of phosphorus fertilizer input in the spring corn area of the arid oasis irrigation area should be 85.02~170.04 kg/hm2 on the premise of ensuring the high yield of spring corn and reducing environmental pollution.

S147.22；S513

国家重点研发计划(2016YFC0400207)。