Research leader Sharon Papiernik, with the Agricultural Research Service (ARS) North Central Agricultural Research Laboratory in Brookings, S.D., used specially designed chambers to test the permeability of dozens of films used to cover fumigated soil. ARS is USDA's chief intramural scientific research agency, and the research supports the USDA commitment to agricultural sustainability.
Papiernik and her colleagues sandwiched each film between two chambers, injected fumigants into one chamber and measured both the fumigant that passed through the film into the second (receiving) chamber and the fumigant that remained in the source chamber.
The researchers tested 200 film-chemical combinations and came up with a "resistance factor" that could be used to determine emission rates for each film and fumigant under a wide range of growing conditions and weather patterns. Because each fumigant had a different chemistry, each behaved differently with each tarp.
The results, reported in the Journal of Environmental Quality, showed that some films were significantly better barriers to fumigant diffusion than others, but their effectiveness varied, depending on the fumigant tested. Some were less effective under higher humidity levels.
The work is part of a special areawide project to find the best alternatives to methyl bromide, which is being phased out as a fumigant because of its harmful effects on the Earth's protective ozone layer. The work also is intended to help the U.S. Environmental Protection Agency (EPA) and other regulators charged with developing new fumigant requirements to better protect those who use them and neighbors of treated fields.
The EPA is adapting the approach as the standard testing method for evaluating agricultural plastics used in soil fumigation. The results, along with those from other studies, have provided basic standards for film manufacturers and guidance for growers on which films offer the best options for reducing fumigant emissions.
Read more about this research in the July 2011 edition of Agricultural Research magazine.
Dennis O'Brien | 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