甘肃农业科技
甘肅農業科技
감숙농업과기
GANSU AGRICULTURAL SCIENCE AND TECHNOLOGY
2014年
6期
6-9
,共4页
投入阈值%氮肥利用率%大白菜%露地栽培
投入閾值%氮肥利用率%大白菜%露地栽培
투입역치%담비이용솔%대백채%로지재배
Threshold%Nitrogen use efficiency%Chinese cabbage%Open field cultivation
通过田间试验，研究了不同施氮量对大白菜产量、氮肥利用率、硝态氮残留量的影响。结果表明，施氮对大白菜有显著的增产作用，但随着施氮量的增加产量变化不大，产量对施氮量的反应呈平台模式。氮肥利用率在3.3%~12.6%，并且随施氮量的增加呈先增加后降低的趋势，在施氮量为656.4 kg/hm2（纯氮300 kg/hm2+有机肥12000 kg/hm2）时，氮肥利用率和作物产量最高。合理控制氮肥用量会促进作物对土壤氮素的吸收。施氮可明显提高0~180 cm剖面土壤NO3--N的累积量，残留的NO3--N的分布随施氮量的增加而显著增加，并且随施氮量的增加残留深度下移，表现出明显的底层累积。各处理土壤氮均集中在0~100 cm土层中，100 cm土层以下，各处理氮含量渐趋一致。综合不同施氮量对大白菜产量以及环境指标的影响，在本试验肥力水平下，大白菜氮肥投入阈值为656.4 kg/hm2（纯氮300 kg/hm2+有机肥12000 kg/hm2）时，能够兼顾作物高产与环境安全。
通過田間試驗，研究瞭不同施氮量對大白菜產量、氮肥利用率、硝態氮殘留量的影響。結果錶明，施氮對大白菜有顯著的增產作用，但隨著施氮量的增加產量變化不大，產量對施氮量的反應呈平檯模式。氮肥利用率在3.3%~12.6%，併且隨施氮量的增加呈先增加後降低的趨勢，在施氮量為656.4 kg/hm2（純氮300 kg/hm2+有機肥12000 kg/hm2）時，氮肥利用率和作物產量最高。閤理控製氮肥用量會促進作物對土壤氮素的吸收。施氮可明顯提高0~180 cm剖麵土壤NO3--N的纍積量，殘留的NO3--N的分佈隨施氮量的增加而顯著增加，併且隨施氮量的增加殘留深度下移，錶現齣明顯的底層纍積。各處理土壤氮均集中在0~100 cm土層中，100 cm土層以下，各處理氮含量漸趨一緻。綜閤不同施氮量對大白菜產量以及環境指標的影響，在本試驗肥力水平下，大白菜氮肥投入閾值為656.4 kg/hm2（純氮300 kg/hm2+有機肥12000 kg/hm2）時，能夠兼顧作物高產與環境安全。
통과전간시험，연구료불동시담량대대백채산량、담비이용솔、초태담잔류량적영향。결과표명，시담대대백채유현저적증산작용，단수착시담량적증가산량변화불대，산량대시담량적반응정평태모식。담비이용솔재3.3%~12.6%，병차수시담량적증가정선증가후강저적추세，재시담량위656.4 kg/hm2（순담300 kg/hm2+유궤비12000 kg/hm2）시，담비이용솔화작물산량최고。합리공제담비용량회촉진작물대토양담소적흡수。시담가명현제고0~180 cm부면토양NO3--N적루적량，잔류적NO3--N적분포수시담량적증가이현저증가，병차수시담량적증가잔류심도하이，표현출명현적저층루적。각처리토양담균집중재0~100 cm토층중，100 cm토층이하，각처리담함량점추일치。종합불동시담량대대백채산량이급배경지표적영향，재본시험비력수평하，대백채담비투입역치위656.4 kg/hm2（순담300 kg/hm2+유궤비12000 kg/hm2）시，능구겸고작물고산여배경안전。
In order to provide evidence for reasonable use of nitrogen fertilizer,a field trial was carried out to examine the effects of the yield and the environmental effects of the chinese cabbage under open field cultivation during 2011-2012 . The results showed that the yield of chinese cabbage was highest at 656.4 kg/hm2 (N 300 kg/hm2+organic manure 12 000 kg/hm2). The nitrogen uptake by chinese cabbage increased with increasing N rate. With N application of 656.4 kg/hm2(N 300 kg/hm2+organic manure 12 000 kg/hm2), the nitrogen uptaked was the highest . With N fertilizer rate increasing,the content of NO3--N in soil layers increased dramatically . With more than 656.4 kg/hm2 (N 300 kg/hm2+organic manure 12 000 kg/hm2)was supplied,soil NO3--N moved down obviously. N fertilizer residual amount increased with increased N fertilizer rate. The nitrogen use efficiency ranged from 3.3%to 12.6%under different rates of N fertilization . At the rate of 656.4 kgN/hm2 (N 300 kg/hm2+organic manure 12 000 kg/hm2)could meet the chinese cabbage demand. These results suggest that the N application rates of 656.4 kg/hm2 (N 300 kg/hm2+organic manure 12 000 kg/hm2),would be optimal for the yield of chinese cabbage and a reduction in the risk of nitrate release into environment .
