文献类型： 外文期刊

作者： Dourado Neto, D. ² ; Powlson, D. ³ ; Abu Bakar, R. ⁴ ; Bacchi, O. O. S. ⁵ ; Basanta, M. V. ² ; Cong, P. Thi ⁶ ; Keerth ¹ ;

作者机构： 1.Univ Calif Davis, Dept Plant Sci, Davis, CA 95616 USA

2.Univ Sao Paulo, ESALQ, Crop Prod Dept, BR-13418970 Piracicaba, SP, Brazil

3.Rothamsted Res, Dept Soil Sci, Harpenden AL5 2JQ, Herts, England

4.Univ Putra Malaysia, Dept Soil Sci, Serdang 43400, Selangor, Malaysia

5.Univ Sao Paulo, CENA, Soil Phys Lab, BR-13416000 Piracicaba, SP, Brazil

6.Inst Agr Sci So Vietnam, Ho Chi Minh City, Vietnam

7.IAEA, Joint FAO, A-100 Vienna, Austria

8.Univ Moulay Ismail, Dept Biol, Fac Sci, Beni Mhamed, Meknes, Morocco

9.Bangladesh Inst Nucl Agr, Soil Sci Div, Mymensingh 2200, Bangladesh

10.Menia Univ, Fac Agr, Dep Agr Microbiol, El Minia, Egypt

11.Univ Peradeniya, Fac Agr, Dept Crop Sci, Peradeniya, Sri Lanka

12.Univ Fed Pelotas, Rural Engn Dept, BR-96001970 Capao De Leao, RS, Brazil

13.Zhejiang Acad Agr Sci, Inst Environm Resources & Soil Fertilizer, Hangzhou, Zhejiang, Peoples R China

14.Univ Co

关键词： Soil Science;Agrichemicals;Agriculture

期刊名称：SOIL SCIENCE SOCIETY OF AMERICA JOURNAL （ 影响因子：2.307； 五年影响因子：2.832 ）

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收录情况： SCI

摘要： In tropical agroecosystems, limited N availability remains a major impediment to increasing yield. A N-15-recovery experiment was conducted in 13 diverse tropical agroecosystems. The objectives were to determine the total recovery of one single N-15 application of inorganic or organic N during, three to six growing seasons and to establish whether the losses of N are governed by universal principles. Between 7 and 58% (average of 21%) of crop N uptake during the first growing season was derived from fertilizer. On average, 79% of crop N was derived from the soil. When N-15-labeled residues were applied, in the first growing season 4% of crop N was derived from the residues. Average recoveries of N-15-labeled fertilizer and residue in crops after the first growing season were 33 and 7%, respectively. Corresponding recoveries in the soil were 38 and 71%. An additional 6% of the fertilizer and 9.1% of the residue was recovered by crops during subsequent growing seasons, There were no significant differences in total N-15 recovery (average 54%) between N from fertilizer and N from residue. After five growing seasons, more residue N (40%) than fertilizer N (18%) was recovered in the soil, better sustaining the soil organic matter N content. Long-term total recoveries of N-15-labeled fertilizer or residue in the crop and sod were similar. Soil N remained the primary source of N for crops. As higher rainfall and temperature tend to cause higher N-15 losses, management practices to improve N use efficiency and reduce losses in wet tropical regions will remain a challenge.