Fertilizer Nitrogen – SCOPE Rapid Assessment Project


Scientific Advisory Committee
Chair: Arvin Mosier (USA), Co-chair: Keith Syers (Thailand); Members: Mateete Bekunda (Uganda), John Freney (Australia), James Galloway (USA), Robert Howarth (USA), Luc Maene (France)


Nitrogen (N) availability is a key factor in food and fiber production. Providing plant available N through synthetic fertilizer in the 20th and early 21st century has contributed substantially to the increased production needed to feed and clothe the increasing human population. To continue to meet the global demands and minimize environmental problems, significant improvements are required in the efficiency with which N fertilizer is utilized within production systems.

There are still major uncertainties regarding the fate of N fertilizer added to agricultural soils and the potential for reducing emissions to the environment. Enhancing the technical and economic efficiency of fertilizer N is seen to promote a favorable situation for both agricultural production and the environment and this has provided much of the impetus for a new N Fertilizer project.

To address this need an assessment of N fertilizer was proposed and approved by SCOPE as part of the International Nitrogen Initiative (INI) that is jointly sponsored by the International Global Biosphere-Geosphere Program (IGBP) and SCOPE. The project was developed as the SCOPE Nitrogen Fertilizer Rapid Assessment Project (NFRAP) and part of an IGBP “Fast Track Initiative” focused on N.

In formulating the N fertilizer project the following key issues were identified:

  1. developing a better understanding and quantification of the fate of fertilizer N added to different farming systems in diverse environments (a regional need)

  2. elaborating the concept of ‘reactive’ N in agricultural systems and putting this in context with other sources of N to waters and the atmosphere (a conceptual and a contextual need)

  3. identifying and assessing the technological and management strategies for enhancing the agronomic efficiency of fertilizer N and reducing emissions to the environment, with positive benefits to the economic efficiency of fertilizer N (a management and societal need)

The objective of NFRAP is to assess the fate of synthetic fertilizer N in the context of overall N inputs to agricultural systems, with a view to enhancing the efficiency of N use and reducing negative impacts on the environment. Regionalization of the assessment highlights the problems of too little available N for crop production to meet the N requirements of sub-Saharan Africa. Considerations were to include:

  1. Methods of measuring fertilizer efficiency with emphasis on improving estimates under on-farm conditions in the world’s major cropping systems.
  2. Regional and sub-regional differences, including those situations where fertilizer N is added in excess or not enough, different farming systems, etc.
  3. The quality of the information needed to assist with policy formulation
  4. Interactions with other nutrients and nutrient cycles
  5. Interactions with other environmental concerns (e.g., C sequestration, greenhouse gas emissions, biodiversity)

Background papers were developed by scientists experienced in issues related to N fertilizers and presented for review. During January 12-16, 2004, the authors of the background papers and 31 other fertilizer N experts from Africa, Asia, Australia, Europe, North America and South America met in Kampala, Uganda to discuss the papers and four cross cutting issues relevant to fertilizer N:

  1. Efficiency of fertilizer N use as determined by product, method and time of application, soil, crop and their interactions
  2. Role of emerging technologies (e.g., genetic enhancement, fertilizer manipulation, and remote sensing and other site-specific precision technologies) on the efficiency of fertilizer N use.
  3. Pathways of N loss and their impacts on human health and the environment (including soil degradation)
  4. Societal responses to meeting N input needs in different regions (including national policies on fertilizer use and promotion of organic agriculture).

The resulting volume, SCOPE 65 Agriculture and the Nitrogen Cycle: Assessing the Impacts of Fertilizer Use on Food Production and the Environment, consists of an overview synthesis paper, four papers developed from the cross- cutting issues, an invited paper which assesses current knowledge on the environmental dimensions of fertilizer N, and the 13 background papers. It was published and presented at the 3rd International Nitrogen Conference in Nanjing on 12-16 October, 2004. The NFRAP Executive Summary is available on line.


Last up-dated 9 June 2005