Habitat modifications are among mankind's most pervasive alterations of our nation's estuarine ecosystems.
When such modifications are extensive, as is the case for the Mobile Bay Causeway, they can alter patterns of natural hydrography. Among the possible consequences of the Causeway is the reduction of water exchange between the fresh water in the lower reaches of Mobile-Tensaw Delta, and the saltier waters of the Gulf of Mexico. If true, this barrier may have created persistent low salinity conditions that local conservationists believe have provided refuge for an exotic species of submerged aquatic vegetation, the Eurasian Milfoil (Myriophyllum spicatum) to survive in during periods when salinity is high throughout this estuary.
When salinity is low, milfoil fragments from these freshwater refuges end up in nearby estuarine grassbeds, where they subsequently outgrow and competitively displace native submerged grasses.
To test these hypotheses, Dr. John Valentine and Marine Technician Susan Sklenar, both of the Dauphin Island Sea Lab (DISL) in Alabama, are currently comparing the results of salinity tolerance experiments they have conducted using milfoil at the DISL with two years of field data which document salinity patterns within the upper reaches of Mobile Bay.
The preliminary results of these experiments suggest that only the most extreme salinities, those observed during hurricane landfalls in the northern Gulf of Mexico, are lethal to milfoil.
"Right after Hurricane Katrina, we noticed that milfoil was not as abundant in those places where it used to be plentiful," recounts Dr. Valentine. "Whether it was the turbidity from the storm or the salinity from waters crashing over the MBC, we're hoping these experiments will be able to help determine the cause."
In the coming year, Dr. Valentine and his colleagues will be conducting additional field experiments to determine if in fact milfoil will outcompete native grasses for habitat within this estuary. It is hoped that these experiments, when completed, will allow DISL to make data-based recommendations for habitat restoration later next year.
Lisa Young | EurekAlert!
Researchers simplify tiny structures' construction drip by drip
12.11.2018 | Princeton University, Engineering School
Mandibular movement monitoring may help improve oral sleep apnea devices
06.11.2018 | Elsevier
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
16.11.2018 | Health and Medicine
16.11.2018 | Life Sciences
16.11.2018 | Life Sciences