Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Meeting the nitrogen management challenge: Arresting the nitrogen cascade

17.02.2003


Nitrogen is central to food production, helping feed almost 40 percent of the world’s growing population, but the element also starts a cascade that moves through the atmosphere, soils, and waters, dramatically altering the environment.



In order to meet future need and preserve the environment, new strategies and opportunities for improved nitrogen management must be developed, scientists said today at the American Association for the Advancement of Science (AAAS) Annual Meeting.

The nitrogen cycle is one of the most important processes in nature for living organisms. Although nitrogen gas is relatively inert, bacteria in the soil are capable of "fixing" the nitrogen into a usable form – fertilizer – for plants. Humans and animals consume the plant material where the nitrogen has been incorporated into their system, primarily as protein.


Human activity has also altered the nitrogen cycle. The human production of food and energy initiates a process that breaks the triple bond of the nitrogen molecule, creating reactive nitrogen. Ammonia, nitrous oxide, or nitric oxide volatilized to the air, produced by the reactive nitrogen, cascades through environmental reservoirs in the atmosphere, terrestrial ecosystems, and aquatic ecosystems.

The nitrite can make surface and subsurface waters unsuitable for humans, livestock, and wildlife. Air emissions of nitrous oxide cause acidification of soil and water, or regional smog, and can reduce biodiversity on the affected land, impact agricultural and forestry production, and lead to health effects in humans and animals.

"Given the critical need for nitrogen in food production and the sequential nature of the effects of too much nitrogen, it is imperative that strategies be developed to optimize nitrogen management in food and energy production and in environmental protection," said James Galloway of the University of Virginia. "Because the consequences of nitrogen accumulation transcend scientific disciplines, geographical boundaries, and political structures, the development of such strategies will challenge the creative minds of natural and social scientists, economists, engineers, business leaders, and decision makers."

Improved Nitrogen Management

The majority of human-produced reactive nitrogen comes from the Haber-Bosch process to produce fertilizer. It is also created by livestock, fossil fuel and biomass combustion, and chemical production and waste management. The future population, which is expected to increase by two billion in the next twenty years, will require an even larger supply of nitrogen.

Paul Fixen, Potash & Phosphate Institute in Brookings, S.D., said that there needs to be a substantial increase in nitrogen fertilizer efficiency, which represents the proportion of applied nitrogen taken up by the crop and utilized to produce biomass and grain. The remaining nitrogen that is not absorbed goes into the environment.

While there has been an improvement in nitrogen fertilizer management, much could still be done to improve the amount of nitrogen that is taken up by crop plants. This effort will require target research and educational programs, Fixen added.

Kenneth Cassman, University of Nebraska, added that a knowledge gap must be bridged in order to improve nitrogen fertilizer efficiency. While there has been significant progress in the development of dynamic crop simulation models to predict crop growth and nitrogen demand, there has been little progress in developing robust soil nitrogen models to predict nitrogen supply.

Cassman noted that because there is an inadequate fundament understanding of the processes which govern short-term nitrogen cycling, it is difficult to estimate the soil nitrogen supply, which is a critical parameter for calculating fertilizing needs. While the scientific challenges must eventually be addressed, interim technological options to improve nitrogen fertilizer efficiency, such as geospatial analysis of soil properties and crop growth, should be employed.

Nitrogen’s Impact on Ecosystems and Economics

"There are significant economic costs associated with the inefficient use of fertilizer, and by the damage caused to aquatic, terrestrial, and marine ecosystems, to the ozone layer and through the climate change by the introduction of reactive nitrogen," said William Moomaw of Tufts University.

"Only one quarter to one-third of applied fertilizer nitrogen is actually absorbed by crops," Moomaw added. "The nitrogen that is unutilized constitutes a straightforward economic loss that can be best reduced through more efficient forms and applications."

For example, some of the unabsorbed nitrogen cascades through surface and subsurface aquatic systems, which leads to a decline in fisheries production and recreational value in the area. But there are also additional remediation costs associated to returning the water systems to their unpolluted state. Estimates of the economic damage or benefits can be interred from productivity changes relative to pristine conditions.

But the estimates of damage can vary widely, Moomaw added. While the goal of constructing a full economic nitrogen cycle is yet to be achieved, there has been progress. Creating a more accurate economic analysis will assist policy makers in determining the most cost effective points for intervention and in the development of policies that address nitrogen emission reductions.


The American Association for the Advancement of Science (AAAS) is the world’s largest general scientific society, and publisher of the journal, Science. Founded in 1848, AAAS serves 134,000 members as well as 272 affiliates, representing 10 million scientists.

Monica Amarelo | EurekAlert!
Further information:
http://www.aaas.org/

More articles from Ecology, The Environment and Conservation:

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Understanding animal social networks can aid wildlife conservation
23.06.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Study shines light on brain cells that coordinate movement

26.06.2017 | Life Sciences

Smooth propagation of spin waves using gold

26.06.2017 | Physics and Astronomy

Switchable DNA mini-machines store information

26.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>