基施缓释肥等氮替代化肥对径流氮素流失和青贮玉米生长的影响

目的]探究配施两种释放方式不同的缓释氮肥对滇中地区坡耕地径流氮素流失及青贮玉米生长的影响，为滇中坡耕地水土保持提供理论依据和支持。方法]通过研究自然降雨条件下的径流槽模拟试验，在等氮条件下设置普通尿素(CK),40%添加了硝化抑制剂的速溶诺泰克^?21+60%普通尿素(处理I)和40%包膜缓释氮肥聚谷氨酸增效3代+60%普通尿素(处理Ⅱ)3个处理。结果]生育期内各处理氮素流失呈先上升后下降的趋势，其中CK流失量最高，处理I和处理Ⅱ较CK有显著减少，总氮流失量分别下降了29.95%和16.77%,硝态氮分别减少了14.55%和6.53%,铵态氮分别减少了16.08%,8.24%。尿素配施缓释氮肥能够有效提高土壤全氮和铵态氮含量，减少硝态氮含量。处理I,Ⅱ较CK相比土壤全氮含量增加了3.25%和0.87%,铵态氮含量分别显著增加了30.57%,25.70%;较CK相比，处理I、处理Ⅱ硝态氮含量分别减少了22.49%和16.61%。结论]3个处理间青贮玉米的产量无显著性差异，但配施缓释肥可以在保证土壤肥力和满足青贮玉米正常生长需求的同时减少坡耕地径流养分流失，其中...

Effects of Base Application Slow-Release Fertilizer Substituting Nitrogen Fertilizers on Nitrogen Loss Along with Runoff and Silage Maize Growth

Objective]The effects of applying two types of slow-release nitrogen fertilizers with different release modes on runoff nitrogen loss and silage maize growth in sloping land in central Yunnan was investigated to provide theoretical basis and support for soil and water conservation in sloping land in central Yunnan. Methods] The runoff trough simulation experiment under natural rainfall conditions was studied, and ordinary urea was set under equal nitrogen conditions(CK), 40% instant Nortec ^21 with added nitrification inhibitor+60% ordinary urea(treatment I)and 40% coated slow-release nitrogen fertilizer polyglutamic acid synergistic 3 generations+60% ordinary urea(treatment Ⅱ)). Results] The nitrogen loss of each treatment during the growth period showed a trend of increasing first and then decreasing, among which the nitrogen loss of CK was the highest, and the losses of total nitrogen decreased by 29.95% and 16.77% in treatments I and Ⅱ, respectively. Nitrogen decreased by 14.55% and 6.53%, respectively, and ammonium nitrogen decreased by 16.08% and 8.24%, respectively. Urea combined with slow-release nitrogen fertilizer could effectively increase soil total nitrogen and ammonium nitrogen contents and reduce nitrate nitrogen content. Compared with CK, treatments I and Ⅱ increased the soil total nitrogen contents by 3.25% and 0.87%, and the ammonium nitrogen content increased significantly by 30.57% and 25.70%, respectively; compared with CK, the nitrate nitrogen content of treatments I and Ⅱ decreased up 22.49% and 16.61%, respectively. Conclusion] There is no significant difference in the yield of silage maize among the three treatments, but the application of slow-release fertilizer can reduce the runoff nutrient loss of slope farmland while ensuring soil fertility and meeting the normal growth requirements of silage maize Nortec ^21 works better.