Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Help Students Think like Soil Scientists

30.09.2009
Emphasizing cross-disciplinary concepts in teaching soil science courses, such as mass-volume relationships, can help undergraduates learn real-world, problem-solving skills that are crucial to their success in soil science careers.

Drs. Josh Heitman and Michael Vepraskas, North Carolina State University Soil Science Department, highlighted this need for quantitative measurement skills in an article detailing the importance of teaching mass and volume relationships at the undergraduate level. The article is published in the recent issue of the Journal of Natural Resources and Life Sciences Education.

Basic physical concepts, such as mass and volume relationships, are found throughout different scientific disciplines. This provides a framework for cross-disciplinary communication that should be emphasized in undergraduate soils training. For soils students to develop these skills, undergraduate course work highlighting quantitative ways to characterize and describe soils is critical. Soil science-specific terminology can, and should, be maintained, but fundamental, cross-disciplinary definitions must be emphasized so that the terminology is clearly connected to what it means.

Subsidence (i.e. loss of horizon thickness) can provide a clear example to emphasize basic mass-volume concepts for problem solving in soils courses. Drainage of wetland soils for agriculture and other purposes has been a common practice for many years. However, drainage of organic soils results in subsidence through shrinkage, loss of buoyancy, and oxidation of organic matter. More recently, much work has focused on restoration of wetland soils to their original natural condition. Discussing restoration of an organic wetland soil can provide a practical problem solving lesson for teaching about subsidence and mass-volume relationships.

The question of how much the soil has subsided is important to consider. Restoration normally causes the water table to rise to the levels that existed before drainage and subsidence. If a soil has subsided 1 meter, for example, then when restored, the water table will be 1 m above the existing surface, creating ponding and impairing the growth of replanted vegetation. Determining how much soil has subsided can be difficult because there is typically no marker or baseline to indicate the position of the original soil surface prior to drainage. Data are only available to describe current conditions for a particular soil profile. Scientists must make use of mass-volume relationship and inference to assess the amount of subsidence that has occurred. Information about post-drainage and un-drained, offsite horizon thickness, bulk density, and mineral content can be used to develop an estimate of the amount of subsidence.

When approaching this problem, students should be encouraged to consider which mass and volume components of the three-phase (i.e. solid – mineral and organic, liquid, and gas) soil system have been altered by subsidence. Both primary (i.e. loss of buoyancy and shrinkage) and secondary (i.e. oxidation) subsidence must be considered. From there we consider what relationships (e.g. bulk density and mineral content) have changed among these soil phases. Students can evaluate soil profile data obtained from drained and un-drained sites including sand content, bulk density, and horizon thickness. They may then begin to solve the problem by developing their own assumptions or may be guided to the assumptions in the original study:

Careful explanation of this example problem to students in undergraduate course work provides a way to incorporate concepts of mass, volume, soil bulk density, mineral and organic fractions, and subsidence in a practical, problem-solving framework. This, in turn, makes for a better understanding of how to compute other mass-volume soil properties such as water contents and porosity that, in our experience, are difficult for our students to grasp. For instructors, considering this example may also suggest parallel problems involving other applications of important quantitative concepts. Addition of this or similar exercises to undergraduate soils course work can help to equip students with quantitative tools important to success in a multi-disciplinary career environment.

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 American Society of Agronomy (ASA) www.agronomy.org , is a scientific society helping its 8,000+ members advance the disciplines and practices of agronomy by supporting professional growth and science policy initiatives, and by providing quality, research-based publications and a variety of member services.

Sara Uttech | Newswise Science News
Further information:
http://www.agronomy.org

More articles from Science Education:

nachricht Starting school boosts development
11.05.2017 | Max-Planck-Institut für Bildungsforschung

nachricht New Master’s programme: University of Kaiserslautern educates experts in quantum technology
15.03.2017 | Technische Universität Kaiserslautern

All articles from Science Education >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

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...

Im Focus: Circular RNA linked to brain function

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...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

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...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

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...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>