ARS | Publication request: CONTROL OF N TRANSFORMATIONS TO INCREASE NITROGEN USE EFFICIENCY AND PROTECT ENVRIONMENTAL QUALITY, FOR JOURNAL OF EROSION CONTROL.

Submitted to: Meeting Abstract
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 3, 2000
Publication Date: June 10, 2000
Citation: Delgado, J.A. 2000. Control of n transformations to increase nitrogen use efficiency and protect envrionmental quality. J. Erosion Control. 7:(5) 68-75.

Interpretive Summary: Nitrogen (N) is one of the most important nutrients used worldwide to increase and maintain crop production. The fertilizer industry can produce different sources of N in the chemical form such as urea, ammonia (NH3) ammonium (NH4), nitrate (NO3) and other forms of fertilizer. Organic sources of N such as manures and/or biological N2 fixation (e.g. symbiotic association between legumes and Rhizobium spp) are also used across different cropping systems. On average, N use efficiency (NUE) in the US is reported to be about 50%. Recently, Raun and Johnson reported that world wide NUE for cereal production is approximately 33%. For the other 67%, the economical loss worldwide is equivalent to 15.9 billion US dollars. The addition of organic or inorganic N fertilizer can impact trace gas emissions and NO3 leaching mechanistic losses. There is potential to cut these losses by 50% and save billion of dollars worldwide and protect the environment. The potential use of controlled release fertilizers (CRF) and nitrification inhibitors (NI) to increase NUE and reduce mechanistic losses has been studied in Colorado. Both the NI and CRF slow the transformations of the applied urea fertilizer and maintain higher NH4 concentrations 29 days after fertilization. When the CRF was applied at 50% of the rate of traditional farmer practices (TFP), the potato tuber production was the same as with the traditional farmer practices that used twice the amount of N fertilizer. These studies show that there is potential to use NI and CRF to increase NUE and to reduce environmental losses of N from the system.

Technical Abstract: Nitrogen (N) is one of the most important nutrients used worldwide to increase and maintain crop production and in maintaining the sustainability and economical viability of farming systems across the world and of feeding the world population. The industrial production of N fertilizer is driven by the atmospheric dinitrogen fixation as a source of different fertilizer materials such as urea, ammonia, ammonium (NH4), nitrate (NO3) and other chemical forms. Organic sources of N such as manures and/or biological N2 fixation are also used across different agroecosystems. Raun and Johnson reported that world wide N use efficiency (NUE) for cereal production is approximately 33%. For the other 67%, the economical loss worldwide is equivalent to 15.9 billion US dollars. The addition of organic or inorganic N fertilizer can impact trace gases emissions and NO3 leaching mechanistic losses. These are reasons to continue developing new technologies and management practices that can increase the NUE. The potential use of controlled release fertilizers (CRF) and nitrification inhibitors (NI) to increase NUE and reduce mechanistic losses has been studied in Colorado. Both the NI and CRF slow the transformations of the applied urea fertilizer and maintained higher NH4 concentrations 29 days after fertilization. The NUE with the CRF was 16% higher than with the traditional farming practices of two split applications, one at planting, one at hill up and ten fertigations. These studies show that there is potential to use NI and CRF to increase NUE and protect environmental quality.