20 Jul 2007
Nutrient Use Efficiency Articles
Latin American Nutrient Use Efficiency Symposium Proceedings Translated to English
Whether in the large-scale production regions of the Cerrado of Brazil or the Pampas of Argentina or in the small-holder fields of Central American mountain villages, nutrient use efficiency (NUE) will be of growing importance in the future. In November 2009, the International Plant Nutrition Institute (IPNI) presented a Symposium called "Nutrient Use Efficiency" at the XVIII Latin American Congress of Soil Science in San José, Costa Rica. The original proceedings of this Symposium were published in Spanish. The six presentations in the proceedings have been translated to English and are available here as a PDF file, containing 50+ pages. Since the principles of appropriate nutrient management are universal, the first three papers from the symposium focus on general principles. However, because best management practices — which are the in-field manifestation of appropriate nutrient stewardship — are site-specific, the second part of the Symposium proceedings focuses on specific regions of Latin America.
The PDF file posted here is available free for download. It is also available on CD. To obtain the Symposium Proceedings publication in Spanish, contact Dr. José Espinosa at >jespinosa@ipni.net< or Dr. Fernando García at >fgarcia@ipni.net<.
Nutrient Use Efficiency and Effectiveness in North America: Indices of Agronomic and Environmental Benefit
MINERAL FERTILIZERS have made it possible to sustain the world’s growing population, sparing millions of acres of natural and ecologically-sensitive systems that otherwise would have been converted to agriculture. Today, economic and environmental challenges are driving increased interest in nutrient use efficiency. Higher prices for both crops and fertilizers have heightened interest in efficiency-improving technologies and practices that also improve productivity. In addition, nutrient losses that harm air and water quality can be reduced by improving use efficiencies of nutrients, particularly for nitrogen (N) and phosphorus (P).
The world’s population, growing in both numbers and purchasing power, is projected to consume more food, feed, fiber, and fuel—increasing global demand for fertilizer nutrients. Since fertilizers are made from non-renewable resources, pressure to increase their use efficiencies will continue. At the same time, efforts should increase to enhance fertilizer use effectiveness for improved productivity and profitability of cropping systems.
Recent Developments of Fertilizer Production and Use to Improve Nutrient Efficiency and Minimize Environmental Impacts
This chapter was written by S. H. Chien, L. I. Prochnow, and H. Cantarella, and published in 2009 in Advances in Agronomy, volume 102. We thank Elsevier Inc. for authorizing its public distribution.
Information is provided on some recent developments of fertilizer production and use that improve nutrient efficiency and minimize environmental impact. The nutrients discussed are mainly N, P, and S.
Improving N nutrient efficiency includes use of (1) controlled-release coated urea products, (2) slow release urea–aldehyde polymer products, (3) urea supergranules for deep placement, (4) nitrification inhibitors to reduce nitrate leaching and denitrification, (5) urease inhibitors to reduce ammonia volatilization from urea, and (6) ammonium sulfate to enhance N efficiency of urea.
Improving efficiency of conventional P fertilizers includes use of (1) coated water-soluble P fertilizers, (2) urea supergranules containing P and K nutrients, and (3) fluid P fertilizers. Use of nonconventional P fertilizers includes (1) phosphate rock (PR) for direct application with a newly developed computer-based phosphate rock decision support system (PRDSS), (2) a mixture of PR and water-soluble P sources, (3) calcined nonapatite PR for direct application, and (4) nonconventional acidulated P fertilizers containingwater-insoluble but citrate-soluble P compounds.
The agronomic effectiveness of newly developed granular NP fertilizers containing elemental S to provide S nutrient is discussed.
Two processes of producing (1) partially acidulated P fertilizers and (2) compound fertilizers of NP and K by bulk blending are recommended for reducing Cd uptake from P fertilizers by crops. The use of these nonconventional fertilizers may result in an increased relative economic benefit with respect to the use of conventional fertilizers in terms of saving fertilizer cost, enhancing nutrient efficiency, or increasing crop yield.