Dataset Information

Global nitrogen budgets in cereals: A 50-year assessment for maize, rice, and wheat production systems.

ABSTRACT: Industrially produced N-fertilizer is essential to the production of cereals that supports current and projected human populations. We constructed a top-down global N budget for maize, rice, and wheat for a 50-year period (1961 to 2010). Cereals harvested a total of 1551?Tg of N, of which 48% was supplied through fertilizer-N and 4% came from net soil depletion. An estimated 48% (737?Tg) of crop N, equal to 29, 38, and 25?kg?ha(-1)?yr(-1) for maize, rice, and wheat, respectively, is contributed by sources other than fertilizer- or soil-N. Non-symbiotic N2 fixation appears to be the major source of this N, which is 370?Tg or 24% of total N in the crop, corresponding to 13, 22, and 13?kg?ha(-1)?yr(-1) for maize, rice, and wheat, respectively. Manure (217?Tg or 14%) and atmospheric deposition (96?Tg or 6%) are the other sources of N. Crop residues and seed contribute marginally. Our scaling-down approach to estimate the contribution of non-symbiotic N2 fixation is robust because it focuses on global quantities of N in sources and sinks that are easier to estimate, in contrast to estimating N losses per se, because losses are highly soil-, climate-, and crop-specific.

SUBMITTER: Ladha JK

PROVIDER: S-EPMC4726071 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Global nitrogen budgets in cereals: A 50-year assessment for maize, rice, and wheat production systems.

Ladha J K JK Tirol-Padre A A Reddy C K CK Cassman K G KG Verma Sudhir S Powlson D S DS van Kessel C C de B Richter Daniel D Chakraborty Debashis D Pathak Himanshu H

Scientific reports 20160118

Industrially produced N-fertilizer is essential to the production of cereals that supports current and projected human populations. We constructed a top-down global N budget for maize, rice, and wheat for a 50-year period (1961 to 2010). Cereals harvested a total of 1551 Tg of N, of which 48% was supplied through fertilizer-N and 4% came from net soil depletion. An estimated 48% (737 Tg) of crop N, equal to 29, 38, and 25 kg ha(-1) yr(-1) for maize, rice, and wheat, respectively, is contributed ...[more]

PMID: 26778035

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Dataset Information

Global nitrogen budgets in cereals: A 50-year assessment for maize, rice, and wheat production systems.

Publications

Global nitrogen budgets in cereals: A 50-year assessment for maize, rice, and wheat production systems.

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