Contributions of Different N Sources to Crop N Nutrition in a Chinese Rice Field

作     者：CHEN Yi,TANG Xu,YANG Sheng-Mao,WU Chun-Yan and WANG Jia-Yu Institute of Environmental Resources and Soil Fertilizer,Zhejiang Academy of Agricultural Sciences,Hangzhou 310021 (China) 

作者机构：Institute of Environmental Resources and Soil Fertilizer Zhejiang Academy of Agricultural Sciences Hangzhou 310021 (China) 

出 版 物：《Pedosphere》 (土壤圈（英文版）)

年 卷 期：2010年第20卷第2期

页      面：198-208页

核心收录：

学科分类：0818[工学-地质资源与地质工程] 09[农学] 0903[农学-农业资源与环境] 0901[农学-作物学] 090301[农学-土壤学] 

基　　金：Project supported by the International Atomic Energy Agency/FAO Division (No. CRP-8896) 

主　　题：crop residue 15 N recovery N fertilizer 

摘      要：N availability is one of the most important factors limiting crop yield *** recovery of applications of 15 N-labeled fertilizer and crop residues in a rice-wheat cropping system was determined for up to 6 consecutive growing *** crop residues from the previous season were either incorporated or removed as two different *** results showed that 16.55%-17.79% (17.17% on average) of the fertilizer N was recovered in the crop during the first growing season,suggesting that more than 80% of crop N was not directly from the N *** 15 N-labeled residues were applied,12.01% was recovered in the crop in the first growing *** average recoveries of fertilizer N and crop residue N in the soil after the first growing season were 33.46% and 85.64%,respectively.N from soil organic matter contributed approximately 83% of the N in the crop when 15 N fertilizer was applied or 88% when crop residues were *** was a larger difference in the total 15 N recovery in plant and soil between N applications in the forms of fertilizer and crop *** of crop residues following the 15 N fertilizer application did not significantly promote 15 N recovery in the crop or *** average,only additional 1.94% of N for the fertilizer-applied field or 5.97% of N for the crop residue-applied field was recovered by the crops during the 2nd and 3rd growing *** total recoveries of 15 N in crop and soil were approximately 64.38% for the fertilizer-applied field after 6 growing seasons and 79.11% for the crop residue-applied field after 5 growing *** fertilizer N appeared to be more readily available to crops than crop residue N,crop residue N replenished soil N pool,especially N from soil organic matter,much more than fertilizer ***,crop residue N was a better source for sustaining soil organic *** results suggested that the long-term effect of fertilizer or crop residues on N recovery were differen