氮肥减施对养分在潮土肥际微域中迁移过程的影响

肥料减施增效对合理控制肥料用量、推进农业绿色发展、实施乡村振兴具有重要意义。本研究以尿素、磷酸二铵和硫酸钾为供试肥料，采用培养试验研究了氮肥减施对砂质潮土和壤质潮土肥际微域速效养分迁移过程的影响。以高产推荐施肥N 210 kg/hm²为基础，在氮肥减施20%时，速效氮磷钾进入砂质潮土肥际微域的比例比习惯施肥N315kg/hm²增加了15.71%、7.27%和13.14%，比高产推荐施肥增加了10.54%、3.79%和8.98%。速效氮迁移距离低于习惯施肥，与高产推荐施肥相当，为46 mm；有效磷迁移距离与两者无显著性差异；速效钾迁移距离分别增加了15.79%和10.00%。速效氮和有效磷进入壤质潮土肥际微域的比例比习惯施肥增加了53.08%、3.44%，比高产推荐施肥增加了14.28%、6.89%，迁移距离与习惯施肥、高产推荐施肥无显著性差异；速效钾比例和迁移距离则低于其他两个施肥量处理。

Effect of Nitrogen Reduction on Migration of Nutrients in Fertisphere of Fluvo-aquic Soil

Reducing fertilizer application and promoting efficiency is of great significance for rationally controlling fertilizer usage, promoting green agricultural development, and implementing rural revitalization. In this study, using urea, diammonium phosphate and potassium sulfate as the test fertilizers, the soil column culture experiments were used to study the effect of nitrogen fertilizer reduction on the migration of available nutrients in fertisphere of sandy and loamy fluvo-aquic soil. Based on the high-yield recommended fertilization of 210 N kg/ha, when the nitrogen fertilizer application was reduced by 20%, the proportion of available nitrogen, phosphorus and potassium in fertisphere of sandy fluvo-aquic soil increased by 15.71%, 7.27% and 13.14% compared with the habitual fertilization of 315 N kg/ha, and increased by 10.54%, 3.79% and 8.98% compared with the high-yield recommended fertilization. The migration of available nitrogen was lower than that of habitual fertilization, and was equivalent to the high-yield recommended fertilization, which was 46 mm; there was no significant difference in the migration of available phosphorus among the three fertilization treatments, and the migration of potassium increased by 15.79% and 10.00%, respectively. The proportion of available nitrogen and phosphorus in fertisphere of loamy fluvo-aquic soil increased by 53.08% and 3.44% compared with the habitual fertilization, and increased by 14.28% and 6.89% compared with the high-yield recommended fertilization; there were not significantly different in the migration of available nitrogen and phosphorus from that of habitual fertilization and high-yield recommended fertilization; the proportion and migration of available potassium were lower than those of the other two treatments.