Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Natural radioactivity used to determine seasonal changes in groundwater supply


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:

More articles from Earth Sciences:

nachricht Jacobs University supports new mapping of Mars, Mercury and the Moon
21.03.2018 | Jacobs University Bremen gGmbH

nachricht Thawing permafrost produces more methane than expected
20.03.2018 | GFZ GeoForschungsZentrum Potsdam, Helmholtz Centre

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

New 4-D printer could reshape the world we live in

21.03.2018 | Life Sciences

Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

21.03.2018 | Trade Fair News

Physicists made crystal lattice from polaritons

20.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>