有机肥替代化肥氮对稻田田面水氮素浓度变化及产量的影响

Effects of Replacing Chemical Fertilizer Nitrogen with Organic Fertilizer on Changes of Nitrogen Concentration in Paddy Field Surface Water and Rice Yield

在等氮量投入条件下,通过田间试验,探讨有机肥替代化肥氮比例对稻田田面水氮浓度变化及产量的影响。结果表明:各施肥处理水稻田面水氮素浓度变化趋势基本一致,均在1~2 d达到峰值,然后逐渐下降,施肥后1周内是防控氮素流失的关键时期;稻季3次施肥后,与单施化肥处理相比,有机肥替代化肥氮处理田面水全氮(TN)平均浓度分别降低了46.14%~71.01%、19.54%~50.53%和60.34%~80.12%,NH_(4)^(+)-N平均浓度分别降低了52.98%~73.37%、17.58%~54.53%和38.16%~86.15%;单季稻有机肥替代化肥氮比例为20%~40%,可维持水稻的增产稳产,同时可有效降低农业面源污染风险,减少环境污染负荷。

A field experiment was conducted to investigate the effects of different proportions of replacement of chemical nitrogen fertilizer with organic manure on nitrogen dynamics in surface water and rice yield under the same amount of total nitrogen input.The results showed that the concentrations of TN,NH_(4)^(+)-N and NO_(3)^(-)-N in surface water reached the peak in 1-2 days after fertilization for each treatment and then decreased to a low level gradually.The critical period to control nitrogen loss was within a week after fertilization.After three times of fertilization in the rice season,the average concentration of TN decreased by 46.14%-71.01%,19.54%-50.53%and 60.34%-80.12%in surface water of the organic fertilizer replacing chemical nitrogen treatment;However,NH_(4)^(+)-N decreased by 52.98%-73.37%,17.58%-54.53%and 38.16%-86.15%,respectively.Partial replacement(20%-40%)of chemical N with organic fertilizer could serve as an effective solution to the problem of agricultural non-point source pollution and the risk of food security.