Soil variation occurs across multiple geographic scales ranging from vast climatic regions of the Earth to a 50 acre farm field to the molecular world of soil nano-particles in a pinch of soil.
For example, in a forest or an agricultural field, soil properties vary from the summit of a hill down to the base. Within a single soil aggregate that may be less than a quarter inch in diameter, there is a variable distribution of open spaces (soil pores), solids (soil particles), and water and gas molecules, and within each of the elements themselves there is variation, such as different pore shapes and different elemental solids.
Many approaches have been used to examine soil variation at these diverse scales, but there is a common difficulty among methods in separating out random variations from systematic variations. Some of the variation observed in, say, a desert community or a handful of soil is random, but other variation is predictable (systematic) based on variables such as landscape position, climate, or time of the year.
New methodological developments better enable us to separate out these different sources of variation by examining soil variability over a range of scales, which is important for linking soil properties with soil processes. These linkages have important predictive capacities, such as forecasting corn yields based on soil characteristics, or understanding where microorganisms live in soil and how human alteration to certain soil properties affects their livelihood.
Scientists from USDA-ARS-NSTL in Iowa, The University of Tennessee, and E.T.S. Ingenieros Agrónomos in Spain have assembled a collection of 12 papers covering a range of original approaches for assessing soil variability across multiple scales. The papers are published in a special section of the May 2008 issue of Vadose Zone Journal.
A variety of multi-scale methods are described and some authors compared the performance of different approaches. The methodologies employed include a variety of sophisticated mathematical approaches including geostatistics (variance of a property depends upon its position in space) and fractals and multi-fractals (similar patterns at different scales), to name a few. The authors then applied these different multi-scale methods to diverse data sets including soil pore shapes, soil aggregates, water content, rate of water movement, gas fluxes, corn yields, geochemical data, and remote sensing data.
“Understanding the interrelationships between physical, chemical, and biological factors at different scales is essential for research in agriculture, engineering, hydrology, and the environment,” says researcher Dr. Sally Logsdon of the USDA-ARS, National Soil Tilth Laboratory, Ames, IA. “Future research should examine how to better mesh together soil data and predictions across landscape position and time scales.”
The full article is available for no charge for 30 days following the date of this summary. View the abstract at http://vzj.scijournals.org/cgi/content/full/7/2/453.
Vadose Zone Journal, http://www.vadosezonejournal.org/ is a unique publication outlet for interdisciplinary research and assessment of the biosphere, with a focus on the vadose zone, the mostly unsaturated zone between the soil surface and the permanent groundwater table. VZJ is a peer-reviewed, international, online journal publishing reviews, original research, and special sections across a wide range of disciplines that involve the vadose zone, including those that address broad scientific and societal issues. VZJ is published by Soil Science Society of America, with Geological Society of America as a cooperator.
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 http://www.soils.org.
SSSA is the founding sponsor of an approximately 5,000-square foot exhibition, Dig It! The Secrets of Soil, opening July 19, 2008 at the Smithsonian's National Museum of Natural History in Washington, DC.
Sara Uttech | newswise
UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine
Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
26.10.2016 | Power and Electrical Engineering
26.10.2016 | Awards Funding
26.10.2016 | Power and Electrical Engineering