Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Ultra-fine Coatings on Sediment Grains Influence Nitrate and Sulfate Storage in Soil

25.02.2009
Vadose zone scientists examine how this thin, complex mineral layer on sediment grains can influence groundwater quality even years after fertilizer application.

Tiny sediment grains are covered with a very fine-grained, complex mixture of minerals in an open fabric that results in a large surface area in contact with water between the grains.

Scientists at the U.S. Geological Survey (USGS) are studying this microscopic layer and finding that the mineral composition of these coatings on sediment grains in the unsaturated zone (i.e., between land surface and the water table) can have a substantial effect on the retention of nitrate and sulfate.

Their findings are particularly important for evaluating the long-term effects of agriculture on water quality, as the storage of these common components of fertilizer in the unsaturated zone can affect the quality of shallow groundwater for many years after fertilizer application ceases.

Nitrate and sulfate are important plant nutrients. Farmers and soil scientists routinely monitor the nutrient content of the soil in farm fields so that fertilizer application can be managed to maintain profitability and to minimize runoff or infiltration. Loss of excess nutrients can elevate levels in streams and shallow groundwater. Understanding the mechanisms of nutrient storage in the unsaturated zone is critical to protecting groundwater resources.

Timothy Reilly, the lead author of the study, stated “The unsaturated zone is potentially a large reservoir for anions (negatively charged ions) like nitrate and sulfate. The increased residence time indicated by these findings suggests that models in areas with similar mineral characteristics, which neglect or minimize storage, will not accurately predict nutrient transport to the water table.”

In the study, unsaturated-zone sediments and the chemistry of shallow groundwater underlying a small (about 3 square miles) watershed in southern New Jersey were studied to identify mechanisms responsible for nutrient storage. Lower unsaturated zone sediments and shallow groundwater samples were collected at 11 locations, and concentrations of nitrate and sulfate were determined. Nutrient storage in the very fine-grained mineral coatings on the sediment grains was attributed to a complex combination of chemical and physical storage mechanisms.

Results from the study, supported by the US Geological Survey Toxic Substances Hydrology Program, were published in the February 2009 issue of the Vadose Zone Journal. The research was also presented in Houston, TX at the joint annual meeting of the Geological Society of America and Soil Science Society of America in October 2008. These findings are particularly important for evaluating the long-term effects of agricultural land use on groundwater quality. Continuing research includes characterizing stream sediments, determining relations between sediment mineralogy and the concentration of pesticides stored on the sediments, and laboratory experiments evaluating storage mechanisms.

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/8/1/75.

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 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 | EurekAlert!
Further information:
http://www.soils.org

More articles from Earth Sciences:

nachricht New insight into glaciers regulating global silicon cycling
14.08.2019 | University of Bristol

nachricht Coastal marine sediments contribute to the formation of greenhouse gases
31.07.2019 | Eberhard Karls Universität Tübingen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Laser für durchdringende Wellen: Forscherteam entwickelt neues Prinzip zur Erzeugung von Terahertz-Strahlung

Der „Landau-Niveau-Laser“ ist ein spannendes Konzept für eine ungewöhnliche Strahlungsquelle. Er hat das Zeug, höchst effizient sogenannte Terahertz-Wellen zu erzeugen, die sich zum Durchleuchten von Materialen und für die künftige Datenübertragung nutzen ließen. Bislang jedoch scheiterten nahezu alle Versuche, einen solchen Laser in die Tat umzusetzen. Auf dem Weg dorthin ist einem internationalen Forscherteam nun ein wichtiger Schritt gelungen: Im Fachmagazin Nature Photonics stellen sie ein Material vor, das Terahertz-Wellen durch das simple Anlegen eines elektrischen Stroms erzeugt. Physiker des Helmholtz-Zentrums Dresden-Rossendorf (HZDR) waren maßgeblich an den Arbeiten beteiligt.

Ebenso wie Licht zählen Terahertz-Wellen zur elektromagnetischen Strahlung. Ihre Frequenzen liegen zwischen denen von Mikrowellen und Infrarotstrahlung. Sowohl...

Im Focus: A miniature stretchable pump for the next generation of soft robots

Soft robots have a distinct advantage over their rigid forebears: they can adapt to complex environments, handle fragile objects and interact safely with humans. Made from silicone, rubber or other stretchable polymers, they are ideal for use in rehabilitation exoskeletons and robotic clothing. Soft bio-inspired robots could one day be deployed to explore remote or dangerous environments.

Most soft robots are actuated by rigid, noisy pumps that push fluids into the machines' moving parts. Because they are connected to these bulky pumps by tubes,...

Im Focus: Crispr-Methode revolutioniert

Forschende der ETH Zürich entwickelten die bekannte Crispr/Cas-Methode weiter. Es ist nun erstmals möglich, Dutzende, wenn nicht Hunderte von Genen in einer Zelle gleichzeitig zu verändern.

Crispr/Cas ist in aller Munde. Mit dieser biotechnologischen Methode lassen sich in Zellen verhältnismässig einfach und schnell einzelne Gene präzise...

Im Focus: Wie schwingen Atome in Graphen-Nanostrukturen?

Innovative neue Technik verschiebt die Grenzen der Nanospektrometrie für Materialdesign

Um das Verhalten von modernen Materialien wie Graphen zu verstehen und für Bauelemente der Nano-, Opto- und Quantentechnologie zu optimieren, ist es...

Im Focus: Vehicle Emissions: New sensor technology to improve air quality in cities

Researchers at TU Graz are working together with European partners on new possibilities of measuring vehicle emissions.

Today, air pollution is one of the biggest challenges facing European cities. As part of the Horizon 2020 research project CARES (City Air Remote Emission...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

VideoLinks
Industrie & Wirtschaft
Veranstaltungen

Gedanken rasen zum Erfolg: CYBATHLON BCI Series 2019

16.08.2019 | Veranstaltungen

Impfen – Kleiner Piks mit großer Wirkung

15.08.2019 | Veranstaltungen

Internationale Tagung zur Katalyseforschung in Aachen

14.08.2019 | Veranstaltungen

VideoLinks
Wissenschaft & Forschung
Weitere VideoLinks im Überblick >>>
 
Aktuelle Beiträge

Laser für durchdringende Wellen: Forscherteam entwickelt neues Prinzip zur Erzeugung von Terahertz-Strahlung

16.08.2019 | Physik Astronomie

Solarflugzeug icaré testet elektrische Flächenendantriebe

16.08.2019 | Energie und Elektrotechnik

Neue Überlebensstrategie der Pneumokokken im Zentralnervensystem identifiziert

16.08.2019 | Biowissenschaften Chemie

Weitere B2B-VideoLinks
IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics