Submitted to: Ecology
Publication Type: Review Article
Publication Acceptance Date: 7/12/2005
Publication Date: 9/1/2005
Citation: Cavigelli, M.A. 2005. Agriculture and the nitrogen cycle. Ecology. 86:2548-2550. Interpretive Summary:
Technical Abstract: Since nitrogen (N) is the nutrient most often limiting to plant growth, a large portion of the tripling of global crop production during the last 50 years--and associated economic development—is due to the widespread use of N fertilizers. The global ecological impact of N fertilizer production also has been impressive. Only about one-half of all fertilizer N is taken up by crops; the remainder is subject to loss to the off-farm environment, where it contributes to some of the most pernicious global environmental challenges we face: acid rain and associated forest decline, global climate change, and eutrophication of surface waters, including severe eutrophication of estuaries worldwide. Since the number of humans on the planet and their per capita consumption rate continue to increase, N fertilizer use and N losses to the environment in the near and distant future are certain to increase globally. This book summarizes the findings of the International Nitrogen Initiative, whose purpose includes assessing and synthesizing current knowledge and recent advances in our understanding of N fertilizers in the global N cycle. The book includes recommendations for increasing food and fiber production while minimizing the release of N to the environment from agricultural systems. The book addresses areas of the world such as sub-Saharan Africa where increased use of N fertilizers can contribute to increased sustainability and also areas such as the more developed countries where increasing nitrogen use efficiency (NUE) on farm fields is seen as the only way to increase food production while reducing loss of N to the environment. Means of increasing NUE are discussed in detail. The authors emphasize that effective policies must recognize that NUE and N losses are spatially variable and N cycle processes are very dynamic. A one-size-fits-all approach will not work. This book provides an excellent introduction to N fertilizer use in agriculture. The book is written by world leaders in the field of N research and global development and despite many multi-authored chapters, it is generally concise, readable and scientifically rigorous. The book provides a forum for competing visions and approaches without losing sight of the overall need to increase NUE in agriculture. The book provides an important case study of the difficulties we face as a species, balancing our short-term needs with long-term sustainability.