Matt Helmers, associate professor of agricultural and biosystems engineering, and Antonio Mallarino, professor of agronomy, have been studying the amount of nitrates that pass through soil into tiling systems from several different types of crops and fertilizer treatments for the past three summers.
The research is funded by the Iowa Department of Agriculture and Land Stewardship and Iowa State's Leopold Center for Sustainable Agriculture.
They found that certain practices can minimize the amount of nitrogen and nitrates that leach from the field into the drainage tiles.
"One of the biggest things we found is that when alternative biomass sources like switchgrass are grown, even when they use fertilizer, we see dramatically lower nitrate concentrations (in the drainage water)," said Helmers.
The research compared fields that were planted with continuous corn while harvesting just the grain; continuous corn taking the grain and stover; and planting continuous corn taking all possible biomass from the fields. Half of those fields were treated with fertilizer and the other half with manure.
Other fields tested systems that rotate corn and soybeans, and others looked at switchgrass plots that received nitrogen fertilizer.
The results showed that fields planted in continuous corn and treated with fertilizer had the most amount of nitrates leach below the crop root zone into the tile system.
The fields with the least amount of nitrates that leached through the soil were planted in switchgrass and treated with fertilizer or manure.
Helmers says that while switchgrass allows less nitrogen to leach into the soil, farmers need reason plant it.
"Right now, there is not necessarily an economic market for (switchgrass)," said Helmers.
"What we're trying to do is evaluate what might be the environmental benefits of that type of land use," he said. "I think that may be able to inform future policy.
"If we pursue a strategy for additional biofuels from various biomass feedstocks, we need to know what the environmental impacts of those different feedstocks are, because that may play into federal policy," Helmers said.
"If there is enough societal benefit and water quality benefit from growing switchgrass on these soils, there may be potential incentives for producers to grow (switchgrass)," he said.
Helmers estimates that at least a third and possibly as much as half of all farmland in Iowa use tile systems to drain excess water from the fields.
Nitrates that leach into the soil can affect Iowa communities that depend on the rivers for clean drinking water, Helmers says.
Nitrates that leach into the soil and are carried downstream are believed to contribute to a dead zone in the Gulf of Mexico where few plants or animals survive.
Overall, there is need for additional information on how biomass feedstock production systems impact nitrate leaching, said Helmers.
"We do frequently get questions about what is the nitrate level leaching from grassland systems compared to corn and soybean," said Helmers.
Matt Helmers | EurekAlert!
Microjet generator for highly viscous fluids
13.02.2018 | Tokyo University of Agriculture and Technology
Sweet route to greater yields
08.02.2018 | Rothamsted Research
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy