【摘要】 为了研究有机肥用量对农田土壤硝态氮迁移累积的影响,合理使用有机肥,减少有机肥对环境的污染,在山东省曹县潮土小麦玉米轮作区进行大田试验,研究了自然降雨条件下不同牛粪有机肥用量对小麦玉米轮作农田土壤硝态氮纵向分布、作物产量、氮素利用率的影响。结果表明:0~100 cm各土层硝态氮含量及累积量随着有机肥用量的增加而增加,且用量为每年每666.7m~2施3 000 kg以上时土壤硝态氮含量显著增加;在小麦生育期和玉米苗期土壤硝态氮含量随着土层深度的增加基本呈先降低后升高的趋势,尤其在初夏小麦成熟期60~100 cm土壤中硝态氮累积量高于表层土,表明该时期土壤硝态氮向土壤深处迁移累积,对雨季地下水污染带来潜在的危害;小麦、玉米产量与牛粪有机肥用量之间分别呈二次函数关系和线性关系,牛粪有机肥用量为每年每666.7m2施3 000 kg(折纯氮45 kg)时小麦和青贮玉米的总产量最高,该用量下,小麦、玉米的氮素利用率分别为52%和50%。综合分析,推荐牛粪有机肥用量为每年每666.7m~2施3 000 kg,既保证小麦、青贮玉米的产量又能降低施肥给环境带来的污染风险。更多还原

【Abstract】 In order to examine the effects of manure application rate on migration and accumulation of nitrate nitrogen（ NO₃^--N） in farmland soil profile and investigate the optimal manure application rate,a field experiment was conducted in wheat-maize rotation area of Caoxian County in Shandong Province. The influences of different cow manure application rates on vertical distribution of soil NO₃^--N,crop yield and nitrogen use efficiency were determined in a winter wheat and summer maize rotation farmland under natural rainfall conditions. The results showed that the NO₃^--N content and accumulation amount in the soil profile（ 0 100cm） increased with the increase of manure application rate. When the manure application rate was greater than 3 000 kg per 666. 7m² for one year,the soil NO₃^--N content was significantly higher than those of other treatments. During the whole wheat growth period and the seedling stage of maize,the NO₃^--N content firstlyreduced and then raised with the increase of soil depth. Especially in wheat mature stage in early summer,the NO₃^--N accumulation amount in the 60 100 cm soil layer was higher than that of topsoil. It indicated that at this period,the NO₃^--N had migrated downward and accumulated in the deep soil,which would be prone to polluting groundwater during the summer rainfall season. The wheat and maize yield showed quadratic function relation and linear relation respectively with the cow manure application rate. The total yield of wheat and silage maize was the highest when the cow manure application rate was 3 000 kg per 666. 7m² for one year（ equivalent to 45 kg pure nitrogen per 666. 7m² for one year）,and the N use efficiency was 52% and 50% respectively. In conclusion,the recommended cow manure application rate was 3 000 kg per 666. 7m² for one year,which could not only guarantee the wheat and maize production but also lower the pollution risk of fertilization to environment.更多还原