Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Natural radioactivity used to determine seasonal changes in groundwater supply

22.11.2002


The discharge of groundwater to coastal waters represents an important source of dissolved nutrients and contaminants that may affect chemical and biological processes in coastal ecosystems. In a journal article published in a recent issue of Limnology and Oceanography, URI Graduate School of Oceanography chemical oceanographers Roger P. Kelly and S. Bradley Moran describe how they used radium isotopes as tracers to determine seasonal changes in groundwater input to the Pettasquamscutt estuary from June 1999 to June 2000.

Radioactive isotopes of the naturally occurring element radium have recently been used as tracers of groundwater input to coastal zones. None of these studies, however, have evaluated seasonal changes in groundwater input. Measuring seasonal changes, as opposed to total input over the course of a year, provides scientists and managers with a more accurate understanding of coastal ecosystems as well as information about the periods of greatest impact over the annual cycle.

The Pettasquamscutt estuary, locally known as the Narrow River, is located adjacent to Narragansett Bay in southern Rhode Island and discharges into Rhode Island Sound. The estuary is approximately 6.5 miles long and has an average depth of 6 feet. Previous studies of the Pettasquamscutt estuary have determined that up to 50% of the freshwater input may be from groundwater.



Radium isotopes in the groundwater of the Pettasquamscutt are derived naturally from the weathering of the underlying metasediment and granite bedrock within the watershed. Using a mathematical model that considers the exchange of water between the river and Rhode Island Sound, the amount of radium desorbed from particles suspended in the water, and groundwater supply, Kelly and Moran observed seasonal changes in groundwater input to the estuary by measuring the excess radium derived from groundwater.

They determined that groundwater input was highest in the summer, lowest in the winter, and intermediate in the spring and fall. Kelly and Moran also estimated the quantity of inorganic nitrogen and phosphorous supplied by groundwater. They speculate that seasonal changes in groundwater supply of these nutrients may influence the occurrence of phytoplankton bloom events in such coastal systems through the annual cycle.

"There is a real need for reliable data on groundwater supply as demands on fresh water reservoirs continue to increase," said Moran.



The URI Graduate School of Oceanography is one of the country’s largest marine science education programs, and one of the world’s foremost marine research institutions. Founded in 1961 in Narragansett, RI, GSO serves a community of scientists who are researching the causes of and solutions to such problems as acid rain, harmful algal blooms, global warming, air and water pollution, oil spills, overfishing, and coastal erosion. GSO is home to the Coastal Institute, the Coastal Resources Center, Rhode Island Sea Grant, the Institute for Archaeological Oceanography, and the National Sea Grant Library.


Lisa Cugini | EurekAlert!
Further information:
http://aslo.org/lo/toc/vol_47/issue_6/1976.pdf

More articles from Earth Sciences:

nachricht NASA eyes Pineapple Express soaking California
24.02.2017 | NASA/Goddard Space Flight Center

nachricht 'Quartz' crystals at the Earth's core power its magnetic field
23.02.2017 | Tokyo Institute of Technology

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>