Fate of ^(15)N-Labeled Urea Under a Winter Wheat-Summer Maize Rotation on the North China Plain  

作　　者：JU Xiao-Tang LIU Xue-Jun PAN Jia-Rong ZHANG Fu-Suo 

机构地区：[1]Key Laboratory of Plant-Soil Interactions, Ministry of Education College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 （China） [2]Institute of Application of Atomic Energy, Chinese Academy of Agricultural Science, Beijing 100094 （China）

出　　处：《Pedosphere》2007年第1期52-61,共10页土壤圈（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Nos. 40571071, 30390080 and 30370287);the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0511).

摘　　要：A field experiment was conducted to investigate the fate of ^15N-labeled urea and its residual effect under the winter wheat （Triticum aestivum L.） and summer maize （Zea mays L.） rotation system on the North China Plain. Compared to a conventional application rate of 360 kg N ha^-1 （N360）, a reduced rate of 120 kg N ha^-1 （N120） led to a significant increase （P 〈 0.05） in wheat yield and no significant differences were found for maize. However, in the 0-100 cm soil profile at harvest, compared with N360, N120 led to significant decreases （P 〈 0.05） of percent residual N and percent unaccounted-for N, which possibly reflected losses from the managed system. Of the residual fertilizer N in the soil profile, 25.6%-44.7% and 20.7%-38.2% for N120 and N360, respectively, were in the organic N pool, whereas 0.3%-3.0% and 11.2%-24.4%, correspondingly, were in the nitrate pool, indicating a higher potential for leaching loss associated with application at the conventional rate. Recovery of residual N in the soil profile by succeeding crops was less than 7.5% of the applied N. For N120, total soil N balance was negative; however, there was still considerable mineral N （NH4^＋-N and NO3^--N） in the soil profile after harvest. Therefore, N120 could be considered ngronomically acceptable in the short run, but for long-term sustainability, the N rate should be recommended based on a soil mineral N test and a plant tissue nitrate test to maintain the soil fertility.一个地实验被进行在冬小麦(Triticum aestivum L.) 和夏天玉米(Zea mays L.) 下面调查 15N 标签脲和它的剩余效果的命运诺思中国平原上的旋转系统。比作 360 kg N 的常规申请率哈 ? 1 (N360 ) ， 120 kg N 的减少的率哈 ?(N120 ) 1 导致了重要增加(P < 0.05 ) 在小麦，产量和没有重要差别被作出对有利的裁决玉米。在在收获的 0 100 厘米土剖面，与 N360 相比， N120 不管多么导致了重要减少(P < 0.05 ) 百分比剩余 N 和百分比未予说明的 N，它可能从管理系统反映了损失。在土剖面的剩余化肥 N 25.6%44.7%和20.7%分别地，，38.2%为 N120 和 N360 在器官的 N 水池0.3%3.0%和11.2%相应地，24.4%在硝酸盐水池，显示一个更高的潜力因为沥滤的损失以常规率与申请联系了。在由接替庄稼的土剖面的剩余 N 的恢复是不到 7.5% 应用 N。为 N120，全部的土壤 N 平衡是否定的；然而，仍然有可观的矿物质 N (NH+4-N 并且没有 ? 3-N ) 在在收获以后的土剖面。因此， N120 能在短期内被认为农学的联盟者可接受，要不是长期的可持续性， N 率应该基于土壤矿物 N 测试和植物组织硝酸盐测试被推荐维持土壤肥力。

关 键 词：^15N-labeled urea nitrogen recovery nitrogen residual effect North China Plain winter wheat-summer maize rotation 

分 类 号：S512[农业科学—作物学]