%0 Journal Article
%T NO3--N Dynamics in a Spring Wheat and Radish Multiple-Crop System in the Hetao Irrigation District<br>河套灌区春小麦-萝卜复种模式下土壤NO3--N动态
%A FENG Zhao-zhong
%A WANG Xiao-ke
%A FENG Zong-wei
%A <br>冯兆忠
%A 王效科
%A 冯宗炜
%J 环境科学
%D 2006
%I 
%X The NO3(-)-N dynamics of the soil, soil solution and groundwater were studied under spring wheat and radish multiple-crop system in Hetao Irrigation District over two years. A strong tendency of NO3(-)-N to move from upper layer to deeper layer could be observed and soil NO3(-)-N was increased at the layer of 100 approximately 150cm. NO3(-)-N concentration of soil solution at the depth of 70 and 120 cm was significantly higher than that at the depth of 30 cm, especially in the radish growth season. NO3(-)-N leaching amount was correlated with deep percolation at both different crop growth seasons and different years and it accounted for higher than 30% of total N input across two years. In the fertilizer plot, the concentration of NO3(-)-N in groundwater was far higher than that in the non-fertilizer plot, and 65.5% samples were over the safe standard of WHO (11.3mg/L) in the fertilizer plot. The topsoil NO3(-)-N content was markedly decreased during the two years multiple-crop system. However, NO3(-)-N leaching was inevitable in the near future due to a large amount of residual NO3(-)-N in the middle and deeper soil profiles.
%K NO3--N leaching
%K spring wheat and radish multiple-crop system
%K groundwater
%K arid areas
%K Hetao Irrigation District<br>NO3--N淋失
%K 春小麦-萝卜复种
%K 地下水
%K 干旱地区
%K 河套灌区
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=3FF3ABA7486768130C3FF830376F43B398E0C97F0FF2DD53&cid=A7CA601309F5FED03C078BCE383971DC&jid=64CD0AA99DD39F69401C615B85F123EF&aid=A5D255882CF21255&yid=37904DC365DD7266&vid=DB817633AA4F79B9&iid=B31275AF3241DB2D&sid=7C786AA9670CF26C&eid=323ACE6C9CE37BAB&journal_id=0250-3301&journal_name=环境科学&referenced_num=0&reference_num=11