North Carolina State researchers recently discovered a test that quickly predicts nitrogen levels in the humid soil conditions of the southeastern United States. These scientists report that the Illinois Soil Nitrogen Test (ISNT) can assess the nitrogen levels in soil with more accuracy than current soil-based tests. This test will allow growers to cut back on the amount of nitrogen-based fertilizer added to soil, leading to economic and environmental benefits.
The proper management of nitrogen is critical to the success of many crop systems. Based on an assessment of the natural amount of nitrogen in soil, growers calculate their optimum nitrogen rates, the concentration of nitrogen that must be present in fertilizer in order to achieve expected crop yields. Under- and over-applying nitrogen fertilizer to corn crops often leads to adverse economic consequences for corn producers. Excess levels of nitrogen in nature also pose serious threats to environment. Agricultural application of nitrogen has been linked to rising nitrate levels and subsequent death of fish in the Gulf of Mexico and North Carolina’s Neuse River.
"Although offsite nitrogen contamination of ground and surface waters could be reduced if nitrogen rates were adjusted based on actual field conditions, there is currently no effective soil nitrogen test for the humid southeastern U.S.," said Jared Williams, lead author of the North Carolina State study that was published in the March-April 2007 issue of the Soil Science Society of America Journal. This research was supported in part by USDA Initiative for Future Agricultural and Food Systems (IFAFS) grant.
From 2001 to 2004, scientists collected and tested the soil from 35 different sites in North Carolina. According to the North Carolina scientists, the collected soil samples were representative of millions of hectares in agricultural production in the southeastern USA. Corn was planted at each site with a range of nitrogen fertilizer rates, and the optimum nitrogen rates and the soil assay results were compared among the sites.
From the collected samples, researchers discovered that the Illinois Soil Nitrogen Test (ISNT) could be used to accurately measure the economic optimum nitrogen rates (EONR) of southeastern soils, despite moderate weather variation over the collection period. While the test can be used to predict the optimum nitrogen rates, the relationship between ISNT and EONR varied by soil drainage class. Researchers believe that these differences represent differences in organic matter that lead to less mineralization and/or more denitrification on poorly drained soils. The results indicate that the Illinois Soil Nitrogen Test can serve as a model for predicting economic optimum nitrogen rates on well- and poorly drained soils and show promise as a tool for nitrogen management.
"Additional research is needed to calibrate and validate the EONR versus ISNT relationships under a wider variety of conditions," says Williams. "Because the Illinois Soil Nitrogen Test predicted EONR robustly to different cost/price ratios, ISNT has the potential to modify or replace current nitrogen recommendation methods for corn."
Light green plants save nitrogen without sacrificing photosynthetic efficiency
21.11.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign
Filling intercropping info gap
16.11.2017 | American Society of Agronomy
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Physics and Astronomy
21.11.2017 | Life Sciences