作物学报2012，Vol.38Issue(1)：148-158,11.DOI:10.3724/SP.J.1006.2012.00148
小麦/玉米/大豆和小麦/玉米/甘薯套作对土壤氮素含量及氮素转移的影响
Effect of Wheat/Maize/Soybean and Wheat/Maize/Sweet Potato Relay Strip Intercropping on Soil Nitrogen Content and Nitrogen Transfer
摘要
Abstract
The aim of this study was to characterize nitrogen transfer in the relay strip intercropping system of wheat/ maize/soybean, and to investigate the N promotion mechanism. A pot experiment was conducted to determine the soil N content and transfer in the relay strip intercropping of wheat/maize/soybean and wheat/maize/sweet potato using the direct 15N foliar feeding technique. The N application rates were 0, 150, 300, and 450 kg ha"1. The results showed that N application increased the soil total N contents in wheat and maize seasons. The total N content of soil reduced when N applied in an excessive rate, and the highest values of soil total N content appeared at the N rate of 150-300 kg ha"1. Moreover, the soil total N contents in wheat and maize seasons in the relay strip intercropping of wheat/maize/soybean were higher than those in the wheat/maize/sweet potato system. After soybean planted in the relay strip intercropping, the soil total N contents increased by 38.6%, 20.2%, 9.4%, and 16.7% at applied N rates of 0, 150, 300, and 450 kg ha"1, respectively. Whereas after sweet potato planted, they were reduced by 3.1%, 1.8%, 14.0%, and 3.8%, respectively. Therefore, the soybean season was beneficial to maintaining soil fertility. The soil NO3-N contents in wheat and maize seasons increased with the raising of N application rate, and the values in wheat/maize/soybean system were lower than those in wheat/maize/sweet potato system. The soil N03-N contents in soybean season were higher than those in sweet potato season. Bi-directional 15N transfer existed in both relay systems. The amount of transferred 15N reduced with the increasing of N application rate. The strength and amount of net transferred 15N in the wheat/maize/soybean system were higher than those in the wheat/maize/sweet potato system. The amounts of net transferred 15N in wheat, maize, and soybean in the wheat/maize/soybean system increased by 3.3-12.1%, 27.0-166.2%, and 26.2-78.7% compared to the corresponding crops in the wheat/maize/sweet potato system, respectively. Moreover, the directions of the 15N transfer were evident, which were from maize to wheat, from soybean to maize, and from maize to sweet potato.关键词
小麦/玉米/大豆/套作/土壤氮素/氮素转移/15N富积标记法Key words
Wheat/maize/soybean system/ Replay strip intercropping/ Soil nitrogen/ N transfer/ 15N foliar feeding引用本文复制引用
雍太文,杨文钰,向达兵,万燕,刘卫国,王小春..小麦/玉米/大豆和小麦/玉米/甘薯套作对土壤氮素含量及氮素转移的影响[J].作物学报,2012,38(1):148-158,11.基金项目
本研究由国家重点基础研究发展计划(973计划)项目(2011CB 100400)和国家大豆产业技术体系专项(CARS-04-PS19)资助. （973计划）
