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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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Eco Trekking across the Chesapeake Bay Watershed

Thursday, September 2nd, 2010
Sunset on Smith

Sunset on canoes in Tylerton, MD

This summer from August 7th through August 13th, 9 students went on a journey through the Chesapeake Bay watershed. This trip was organized and led by Josh Falk, an Education Specialist at SERC, and Kevin Schabow, an educator at the NOAA Chesapeake Bay Office. The purpose of this trip was to immerse high school age students in the complex nature of the science, culture and natural resources that the Bay’s watershed has to offer. This year, the students were assigned to report on what they learned and what they did. Here is their story.
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Nitrogen Weakens Marshes’ Ability to Hold Back Climate Change

Wednesday, June 30th, 2010

Scientists Find Excess Nitrogen Favors Plants That Respond Poorly to Rising CO2

A photo of a marsh with a boardwalk and plastic chambers surrounding various patches of plants.

The Smithsonian's Global Change Research Wetland. Photo: SERC

As atmospheric carbon dioxide levels rise, so does the pressure on the plant kingdom. The hope among policymakers, scientists and concerned citizens is that plants will absorb some of the extra CO2 and mitigate the impacts of climate change. For a few decades now, researchers have hypothesized about one major roadblock: nitrogen.

Plants build their tissue primarily with the CO2 they take up from the atmosphere. The more they get, the faster they tend to grow—a phenomenon known as the “CO2 fertilization effect.” However, plants that photosynthesize greater amounts of CO2 will also need higher doses of other key building blocks, especially nitrogen. The general consensus has been that if plants get more nitrogen, there will be a larger CO2 fertilization effect. Not necessarily so, says a new paper published in the July 1 issue of Nature.
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Introducing Tintinnophagus acutus

Thursday, June 24th, 2010

Photo of a microscopic dinospore of Tintinnophagus acutus

A Tintinnophagus acutus dinospore, with a flagellum. Photo: Wayne Coats

In the microscopic world of marine protists, many species drift in the ocean currents unstudied and nameless. This is no longer the case for the parasitic dinoflagellate Tintinnophagus acutus. SERC plankton ecologist Wayne Coats recently finished an extensive description of the organism and thus earned naming rights.

Of the approximately 2,000 known species of living dinoflagellates, about 150 are parasitic. These organisms can alter the marine food web, in some cases destroying prey that consumers like copepods and larval fish rely upon. Coats first spotted T. acutus in the 1980s, in plankton samples he had collected from the Chesapeake Bay. Through his microscope, he noticed a ciliate being edged out of its lorica (shell) by a dinoflagellate. It looked different from others he had observed.
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One species, 20 genotypes, 3,808 plants and a plague of voles: Study reveals new benefits of genetic diversity

Thursday, May 27th, 2010

If you’re designing an ambitious field experiment that involves more than 3,800 plants and 240 deer cages, ecologist John Parker has some words of wisdom for you: beware of the unexpected. Beware of meadow voles. Parker is a senior scientist at the Smithsonian Environmental Research Center, in Edgewater, Maryland. He studies the relationship between plants and the herbivores that eat them.

John Parker tends to one of his plants in the field.

Ecologist John Parker examines one of his plants in the field. Photo: Alex Smith

In a recent paper published in Ecology Letters, Parker chronicles the ups, downs and findings of a study investigating the links between genetic diversity in plants and herbivory. “Most people think about biodiversity in terms of species diversity, where you have a rich variety of plants and animals living in an ecosystem,” explains Parker. “I’m interested in exploring the importance of genetic diversity within a species.” Scientists have recently discovered that plants can benefit from growing in genetically-rich polycultures, where neighboring plants of the same species have different genotypes. Parker’s new research shows that these benefits include better protection against hungry herbivores like deer and voles.
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