A new calibration tool was recently developed to help students and soil scientists calibrate their thumb and forefinger for the correct amount of pressure.
C.A. Seybold and colleagues, USDA-NRCS, Lincoln, NE, write about this new tool in the 2009 issue of Journal of Natural Resources and Life Sciences Education.
Rupture resistance is a measure of the strength of a soil to withstand an applied stress or resist deformation. In soil survey, during routine soil descriptions, rupture resistance is described for each horizon or layer in the soil profile. The current rupture resistance classes were developed from the qualitative consistence classes in the 1951 Soil Survey Manual and from studies that developed quantitative class limits. The lower portion of the rupture resistance classes are assigned based on the rupture force exerted between thumb and forefinger.
"The problem is that the tactile sense of the pressure can vary considerably between individuals," explains Seybold.
Here is how the new calibration tool works, according to Seybold. There are four pressure calibration tool assemblies measuring 8, 20, 40, and 80 N of applied pressure. The assemblies consist of a compression spring between two door-pulls (knobs) where the force exerted is calibrated using a top loading balance. Cap screws inserted into the door-pulls are adjusted so that the desired force is exerted just as the cap screws touch. The cap screws differ in height for each assembly.
The calibration tools are demonstrated on how the combinations of spring/knobs are put together to get different rupture pressures. Manufactured or substitute fragments for natural soil fragments are described that can be used in the instruction of rupture resistance in the class room.
Seybold has discovered that, in soil survey, this tool has been effective in calibrating the finger-force range for rupture resistance class placement for the last two decades. The calibration tools have become a part of the tool set carried by field soil scientists for use when describing soils.
The full article is available for no charge for 30 days following the date of this summary. View the abstract at http://www.jnrlse.org/pdf/2009/E08-0011.pdf. After 30 days it will be available at the Journal of Natural Resources and Life Sciences Education website, www.jnrlse.org. Go to http://www.jnrlse.org/issues/ (Click on the Year, "View Article List," and scroll down to article abstract).
Today's educators are looking to the Journal of Natural Resources and Life Sciences Education, http://www.jnrlse.org, for the latest teaching techniques in the life sciences, natural resources, and agriculture. The journal is continuously updated online during the year and one hard copy is published in December by the American Society of Agronomy.
The Soil Science Society of America (SSSA) is a progressive, international scientific society that fosters the transfer of knowledge and practices to sustain global soils. Based in Madison, WI, and founded in 1936, SSSA is the professional home for 6,000+ members dedicated to advancing the field of soil science. It provides information about soils in relation to crop production, environmental quality, ecosystem sustainability, bioremediation, waste management, recycling, and wise land use.
SSSA supports its members by providing quality research-based publications, educational programs, certifications, and science policy initiatives via a Washington, DC, office. For more information, visit www.soils.org.
SSSA is the founding sponsor of an approximately 5,000-square foot exhibition, Dig It! The Secrets of Soil, which opened on July 19, 2008 at the Smithsonian's Natural History Museum in Washington, DC.
Sara Uttech | Newswise Science News
Further reports about: > Calibration Tool > Recycling > Rupture Resistance > Soil > Soil Science > bioremediation > calibrating > crop production > ecosystem sustainability > environmental quality > natural resource > pressure calibration tool > rupture resistance of soils > waste management > wise land use
NASA examines Peru's deadly rainfall
24.03.2017 | NASA/Goddard Space Flight Center
Steep rise of the Bernese Alps
24.03.2017 | Universität Bern
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy