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The Satellite That Could Save the Coasts

Friday, September 16th, 2011

by Kristen Minogue

On a hot afternoon in July, a team of researchers sailing down Chesapeake Bay stumbled across a cluster of striped bass floating in the water. About a dozen of the iridescent black and silver fish bobbed at the surface near the ship’s bow. All of them were dead.

Scientists prepare to measure how light interacts with particles in the Bay. Credit: Carlos DelCastillo

The fish kill came out of a low-oxygen zone near Annapolis, just one symptom of the Bay’s declining health. Overflows of nutrients from farms and cities have fueled massive growths of algae that cut off light and oxygen to the Bay’s lower levels.

“There was a very quiet moment between everybody on the boat,” recalled Vienna Saccomanno, one of the Smithsonian research interns aboard when it was discovered. “You kind of knew what everyone was thinking, feeling empowered to continue with this research and hopefully contribute to prevention of this in our water system.”

The scientists on board weren’t there simply to document the Bay’s many ailments, however. They had joined the 10-day cruise to pave the way for a much larger goal: a geostationary satellite that could provide constant, detailed coverage of coastal health.
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Marshes, Microbes and the Other Blue Carbon

Tuesday, September 6th, 2011

by Kristen Minogue

Tidal marshes have long been lauded as carbon sinks for their ability to pull CO2 from the atmosphere and bury it in the soil, what scientists have taken to calling “blue carbon.” But wetlands are also notorious methane emitters. Now ecologists suspect that only a select few wetland types can reliably act as sinks, and that number may shrink as sea levels rise.

tidal wetland

The Kirkpatrick Marsh on SERC's campus in Edgewater, MD. Tidal wetlands both store and release greenhouse gases. Which will prevail as the planet warms is a question ecologists are still trying to answer. (Credit: Gary Peresta/SERC)

Scientists estimate wetlands are responsible for anywhere from 15 to 45 percent of all methane emissions – a wide range that makes predicting their role in climate change difficult. However, that role could prove critical in the years to come. Methane (CH4) is a far more potent greenhouse gas than carbon dioxide. Over the course of a century, a single gram of methane is roughly 25 times more powerful than a gram of CO2.
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Hunt for a Missing Nutrient

Wednesday, August 17th, 2011

by Kristen Minogue

Leviton

Intern Ginny Leviton (left) and Vienna Saccomanno sample groundwater from a drainage ditch, trying to pin down the exact spot where the nitrogen goes missing. (Credit: Tom Jordan)

The Choptank watershed has SERC researchers baffled. On the eastern shore of Chesapeake Bay, roughly a 75-minute drive from SERC, the groundwater flowing into the Choptank River passes through a cornfield – a likely source of nitrogen, a nutrient that can wreak havoc on the Bay’s ecosystem if it runs too high. But something is happening to the nitrogen here before it reaches the Bay. Nutrient ecologist Tom Jordan and his research team have spent the better part of a year trying to figure out what.
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Intern Logs: Witness to an Invasion

Tuesday, July 19th, 2011

snakehead students

Students on the SERC sampling team, with the 23-inch female snakehead fish they helped ensnare: Diana Sisson (intern), Alison Everett (visiting student), and Philip Choy (intern).

First-hand accounts of the snakehead capture from two interns on the seining survey.

It was around 3 p.m., and it was time to pull the last seine net of the day. We had been out on the water since 10 a.m., and we had already caught a few rarer species, including a stingray and a few juvenile Common Carp. Research biologists Eric Bah and Stacey Havard volunteered to pull what may be the seine of their career.
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Grimy field work? Give it to the tourists.

Tuesday, July 12th, 2011

Ali Kishwar, a volunteer tourist from Pakistan, navigates the muddy terrain across from SERC's beaver pond with caution. (Credit: SERC)

For most people, summer vacation means stretching out on a beach in the South Pacific, touring the ruins of ancient Greece, or (for the more outdoors-inclined) hiking the Inca Trail in Peru. It does not usually entail wading through ankle-deep mud to measure the diameters of trees.

Paul Smith, a 63-year-old retired engineer, travelled to SERC all the way from the United Kingdom to do it. So did Ali Kishwar, a Pakistani doctorate student who took a break from studying medicinal plants at the University of Reading in Berkshire, also in the U.K. Smith and Kishwar joined a motley group of seven citizen scientists who paid to spend a week at SERC doing field work.
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Climate Change & Biodiversity: What’s Next?

Monday, April 25th, 2011

Research suggests some species in the tropics and subtropics may be more resistant to climate change than species closer to the poles. (Credit: SERC)

The threat of radical climate change has made predicting the future of biodiversity a critical challenge for scientists. However, untangling the many intricacies of how climate can affect plant and animal species can also be quite daunting. SERC ecologist Sean McMahon and co-authors, including three Nobel Laureates from the U.N. IPCC report, tackle the issue in a paper published this month in Trends in Ecology and Evolution. Broken down, here’s what we already know about biodiversity and climate, what we still need to know, and what to do next.
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New Genome Helps Crack Methylmercury Code

Friday, April 15th, 2011

A bacterium called Desulfovibrio desulfuricans strain ND132 can transform elemental mercury into methylmercury, a human neurotoxin. Credit: Oak Ridge National Laboratory.

A newly decoded bacterial genome brings scientists one step closer to unlocking the secret behind the production of methylmercury, the chemical notorious for contaminating tuna and other seafood.

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How to Block Ship-borne Bioinvaders Before They Dock

Friday, March 25th, 2011

SERC researcher George Smith opens an air vent on the ship Patcantrell for a ballast water experiment. (Credit: Timothy Mullady/SERC)

The global economy depends on marine transportation. But in addition to cargo, the world’s 50,000-plus commercial ships carry tiny stowaways that can cause huge problems for the environment and economy. A new model, published Thursday in the journal Environmental Science & Technology, will help ships screen more accurately for dangerous species before they unload.

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Discovery on the Mudflats

Thursday, February 3rd, 2011

by Monaca Noble

An orange sponge grows from a bryolith ball.

An orange sponge made this bryolith its home.

What are these rocks doing on the mudflat? That was the question a group of researchers in San Francisco’s South Bay asked in 2005. They were engaged in a native oyster restoration project when they stumbled upon some rather large rocks. They kicked one to the surface and recognized it as a bryozoan colony. SERC researcher Chela Zabin realized that this free-living bryozoan colony was very unusual; normally they grow on hard surfaces. Zabin and Joshua Mackie, of San Jose State University, identified the organism as Schizoporella errata, a type of calcified encrusting bryozoan that usually grows on pilings, boat hulls and docks. 
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Smithsonian Study Measures Watershed-wide Effects of Riparian Buffers on Nutrient Pollution

Wednesday, October 27th, 2010
Aerial photo of farmland and streams - with trees growing in between them.

Well-developed riparian forests outline streams and help protect stream water quality.

Most of the time, nutrients are viewed as a positive and essential part of life. However, excess amounts of a nutrient, like nitrogen, can create major ecological problems for the Chesapeake Bay and other aquatic ecosystems. Too much nitrogen leads to an abundance of microscopic plant growth in the water. When the algae die and decay, they consume the oxygen that other organisms need to thrive.

Much of the Bay’s nitrogen pollution comes from farms where rainwater carries nitrate, a form of nitrogen, from fields into streams that drain into the Bay. For years, ecologists have noted that forests and wetlands growing between croplands and streams can reduce the amount of nitrate that reaches the waterways. Scientists have measured nitrate removal by these “riparian buffers,” but only in small study areas.
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