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作 者 ：刘瑞 戴相林 周建斌 张鹏 崔亚胜 王天泰

期 刊 ：植物营养与肥料学报 2011年 17卷 6期 页码：1335-1341

关键词：冬小麦；施氮量；土壤硝态氮；氮素表观盈亏；

Keywords:winter wheat, N- fertilizer rate, soil NO3-N, apparent N budget in soil,

摘 要 ：以在陕西关中地区户县、周至两县连续2年的20余个“3414”肥料田间试验为研究对象，研究了不同施氮量下冬小麦收获后土壤2 m剖面硝态氮的分布、累积及其与土壤氮素表观盈亏量间的关系。结果表明：随着氮肥用量的提高，土壤剖面硝态氮累积量明显增加，其向土壤下层淋溶的程度也越严重；当施氮量为180～240 kg/hm²时，一些试验点的土壤氮素已经表现出盈余；当施氮量达到270～360 kg/hm²，所有试验点土壤氮素均明显盈余。不同施氮量时土壤表观氮素平衡值（施氮量与氮素携出量的差值）与土壤0—2 m剖面硝态氮累积量之间呈极显著正相关，说明土壤表观氮素平衡和盈亏决定了土壤剖面硝酸盐的累积状况；土壤氮素表观盈余值每增加100 kg/hm²，0—2 m土壤剖面硝态氮累积量增加约62.5 kg/hm²。

Abstract:More than 20 field experiments designed with the “3414” plan were carried out in Huxian County and Zhouzhi County, Guanzhong Plain, Shaanxi during 2008 and 2009 to evaluate the NO3-N accumulation in soil profiles after harvesting winter wheat; and its relationship with the apparent N budget in soil was also studied. The results show the amounts of NO3-N accumulation in the soil profiles and their extents to leach into the deeper soil layers are increased significantly as the nitrogen fertilizer usage increased. When the N fertilizer rate reaches to 180–240 kg/ha, positive budget of nitrogen in soil is observed in some experiment sites, and when N fertilizer rate reaches to the 270–360 kg/ha, positive budget of nitrogen in soil is observed in all experiment sites. There is a positive correlation between the apparent balances of soil N and the accumulation of NO3-N in soil profiles (0–2 m). This indicates the amount of NO3-N in the soil profile is mainly determined by the apparent N budget balances in soil. The NO3-N accumulation in the soil profile is increased about 62.5 kg/ha when N balance in soil is at 100 kg/ha.

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