Recovery of Residual Fertilizer‐Nitrogen by Wheat in a Winter Wheat–Summer Maize Rotation in the North China Plain: A Soil Column Study

摘要: Cropping systems is potentially useful practice for mitigating nitrate leaching and increasing nitrogen use efficiency (NUE) because deeper rooted crops could capture the leached N from previous shallower crops. The recovery of fertilizer (FN) applied to maize (Zea mays L.) by succeeding wheat (Triticum aestivum in a winter wheat―summer rotation North China Plain (NCP) was studied 2003―2004 2005―2006 creating 15 N-labeled soil columns. We found that in-season plant ofFN about 46 48% total residual (RFN) 2-m profile at harvest 34% 41% 2005―2006, ratios unaccounted were 19 12%, respectively. RFN declined significantly down profile. About 13 10% RFN, or 4.4 4.0% FN observed below 1.2 m depth. Wheat able recover up 2.0-m depth, ratio upper layers higher than lower ranged 23% 4.6 2005― 2 006. Corresponding 13.7 21.4% 4.9 8.7% FN, annual 51.6% 56.2% 2005―2006. deep-rooting characteristics deep uptake should be taken as an important index management system.