Assessing the benefits and wider costs of different N fertilisers for grassland agriculture

Autor(es)

Carswell, Alison ^[1] ; Shaw, Rory ^[2] ; Hunt, John ^[1] ; Rafael Sanchez-Rodriguez, Antonio ^{[2, 3]} ; Saunders, Karen ^[1] ; Cotton, Joseph ^[2] ; Hill, Paul W. ^[2] ; Chadwick, Dave R. ^[2] ; Jones, Davey L. ^[2] ; Misselbrook, Tom H. ^[1]

Afiliação do(s) autor(es)

^[1] Rothamsted Res, Sustainable Agr Sci, North Wyke, Devon - England

^[2] Bangor Univ, Sch Environm Nat Resources & Geog, Bangor, Gwynedd - Wales

^[3] Univ Cordoba, Dept Agron, ETSIAM, Cordoba - Spain

• Tipo de documento: Artigo Científico
• Fonte: ARCHIVES OF AGRONOMY AND SOIL SCIENCE; v. 65, n. 5, p. 625-639, APR 16 2019.
• Citações Web of Science: 1

Resumo

Fertiliser nitrogen (N) is essential for maintaining agronomic outputs for our growing population. However, the societal, economic and environmental impacts of excess reactive N from fertiliser is rarely assessed. Here the agronomic, economic and environmental efficacy of three N-fertiliser sources, ammonium-nitrate (AN), urea (U), and inhibited-urea (IU; with NPBT) were evaluated at two grassland sites. Dry matter yield and herbage quality were measured at each silage-cut. Additionally, NH3-N and N2O-N losses were measured and used to calculate the effective N source cost and externality costs, which account for associated environmental and societal impacts. We found no effect of different N sources on yield or herbage quality. However, NH3-N emissions were significantly reduced under the IU treatment, by 48-65%. No significant differences in cumulative N2O emissions were observed. Incorporating externality costs increased fertiliser prices by 1.23-2.36, 6.51-16.4, and 3.17-4.17 times the original cost, for AN, U and IU, respectively, transforming U from the cheapest, to the most expensive of the N sources examined. However, with no apparent yield differences between N-fertiliser sources there is no economic incentive for the land-manager to use the more environmentally and socially acceptable option, unless externality costs are incorporated into fertiliser prices at the point of sale. (AU)

• Processo FAPESP: 15/50305-8 - A virtual joint centre to deliver enhanced nitrogen use efficiency via an integrated soil-plant systems approach for the UK & Brazil
• Beneficiário: Ciro Antonio Rosolem
• Linha de fomento: Auxílio à Pesquisa - Temático