Date of this Version
Dobermann, A., 2007. Nutrient use efficiency—measurement and management. In: Krauss, A., Isherwood, K., Heffer, P. (Eds.), Fertilizer Best Management Practices: General Principles, Strategy for Their Adoption and Voluntary Initiatives Versus Regulations. International Fertilizer Industry Association, Paris, France, pp. 1–28. Online @ https://www.fertilizer.org//images/Library_Downloads/2007_IFA_FBMP%20Workshop_Brussels.pdf
Mineral fertilizers have sustained world agriculture and thus global population and wealth growth for more than 100 years (Smil, 2001; Stewart et al., 2005). Th eir contribution to increasing crop yields has spared millions of hectares of natural ecosystems that otherwise would have been converted to agriculture (Balmford et al., 2005). However, lacking, imbalanced, inappropriate or excessive use of nutrients in agricultural systems remains a concern. Nutrient mining is a major cause for low crop yields in parts of the developing world, particularly Africa. In other situations, nutrients such as nitrogen (N) and phosphorus (P) often move beyond the bounds of the agricultural field because the management practices used fail to achieve good congruence between nutrient supply and crop nutrient demand (van Noordwijk and Cadisch, 2002). If left unchecked, such losses may bear significant costs to society (Mosier et al., 2001). Hence, increasing nutrient use efficiency continues to be a major challenge for world agriculture. This paper tries to summarize how the use efficiency of N, P and potassium (K) from mineral fertilizer is commonly defined and measured, what needs to be considered for interpreting such values, and how it can be improved through soil, crop and fertilizer management. It focuses on cereal systems because those consume the bulk of the world’s fertilizer, but the principles discussed are similar in all agricultural crops. Where possible, attempts are made to discuss differences between developed and developing countries. Two key messages emerge: (i) Nutrient use efficiencies measured under practical farming conditions are mostly lower than those reported from research experiments, but information on current levels of fertilizer use and nutrient use efficiency by different crops, cropping systems and world regions remains insufficient; (ii) Numerous technologies for increasing nutrient use efficiency exist. They have been evaluated thoroughly, but adoption by farmers is lagging behind.