【摘 要】
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Fertilization and tillage have altered global nutrient cycles and caused soil nutrient enrichment.The effects of fertilizers and tillage on soil organic carbon (SOC) storage have been tested in many f
【机 构】
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State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Northwest A&F Universi
【出 处】
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教育部学位管理与研究生教育司,国务院学位委员会办公室
论文部分内容阅读
Fertilization and tillage have altered global nutrient cycles and caused soil nutrient enrichment.The effects of fertilizers and tillage on soil organic carbon (SOC) storage have been tested in many field experiments worldwide.However,the long-term effects of nitrogen (N) fertilization on the profile distribution of SOC,N and phosphorus (P) concentrations and stocks are rarely evaluated;as a result,conflicting findings for these elements have been reported in the literature.To determine the carbon (C),N and P concentrations and stocks in the soil profile after long-term N fertilization at different levels,we measured SOC,soil total N (TN),soil total P (TP) and soil bulk density in a long-term N fertilization experiment using two winter wheat cultivars and five N application rates (0 kg ha-1,90 kg ha-1,180 kg ha-1,270 kg ha-1 and 360 kg ha-1) beginning in 2004.
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