A study recently published in the Journal of Environmental Quality by a team from Cornell University and the University of Illinois-Urbana found that tile drainage systems in upper Mississippi farmlands – from southwest Minnesota to Iowa, Illinois, Indiana and Ohio – are the biggest contributors of nitrogen runoff into the Gulf.
That runoff has been identified as a major contributor to “seasonal hypoxia” or dead zones in which nitrogen fertilized algae blooms, depletes oxygen and suffocates other life forms over thousands of square miles each summer.
“Given the pivotal role of tile drainage in transporting fertilizer nitrogen from agricultural fields to streams and rivers, we need to consider some form of regulation if we expect to reverse hypoxia in the Gulf of Mexico,” said Laurie Drinkwater, associate professor of horticulture and co-author of the paper.
To estimate nitrogen inputs and outputs, the researchers constructed a database that spanned from 1997 to 2006 and included data on crops, livestock, fertilizer, human populations and other information for 1,768 counties. The database also included nitrate concentrations and their flow into streams and rivers from 153. Computer modeling revealed that the dominant source of nitrogen loss into the Mississippi came from fertilized cornfields on tile-drained watersheds in the upper Mississippi River basin.
Drinkwater said solutions include installing wetlands in areas where tiles drain to filter the water and fertilizing fields in the spring instead of the fall. Also, she added, “we know that we are losing nitrogen in the period between cash crops when nothing is growing in the field. If we plant winter cover crops and diversify crop rotations, nitrogen losses could be reduced quite a lot.”
The Mississippi River basin covers 40 percent of the continental United States and is the largest producer of corn and soybeans in the world.
Mark David, a biogeochemist at the University of Illinois, is the paper's lead author. It was also co-authored by Gregory McIsaac at the University of Illinois, and was funded by the National Science Foundation.
John Carberry | Newswise Science News
Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung
Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences