Climate Change

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Day at the Museum: Battle of the Smithsonian Marsh

Thursday, August 5th, 2010

Four people sitting on a boardwalk in a marsh, measuring plants.

Seal collects data with other interns for Smithsonian scientists who are investigating the impact of global change on tidal marshes.

I know the title sounds like another great Ben Stiller Night at the Museum movie. However, in this real story of life at the Smithsonian, you will get a first-hand look at what really goes on behind the scenes at the Smithsonian Environmental Research Center. Although the movies show the Smithsonian as talking exhibits, in reality the Smithsonian is a multitude of museums and scientific research centers where students of all ages and specialties do research. The two movies did a very good job of characterizing some of the more popular characters in history such as Theodore Roosevelt, but in reality the most interesting people at the Smithsonian are the researchers.
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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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Plants, climate change and the importance of being curious, an interview with Bert Drake

Thursday, February 25th, 2010

If you’re looking for a good conversation about science, history or life – talk to Bert Drake. He’s a plant physiologist and renaissance man who’s been with the Smithsonian Environmental Research Center for nearly four decades. Drake retired in January, but will continue his investigations as an emeritus scientist. We caught up with him before he took well-deserved vacation.

Wideshot of Drake on the boardwalk that winds through his marsh research station.

Drake's research unfolds at the Kirkpatrick Marsh, located in Maryland on a subestuary of the Chesapeake Bay.


How did you earn a living before you became a scientist?
I was a drummer in a jazz band, a ski guide, the host of a jazz radio program and a high school science teacher.

How did you get drawn to the world of plant physiology?
Nature has always fascinated me and science is about discovering how nature works. I grew up in northern Maine. My father was a barber, but loved the outdoors. I was outside year-round: skiing, canoeing, trapping animals, fishing and taking photos. I knew I wanted to do something connected with biology. I became a science teacher, but it wasn’t until I attended a summer course in ecology that I wanted to get inside a lab and practice science.

In science you almost always get an approximation of an answer because an experiment is only an approximation of reality.

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Forests are growing faster, climate change most likely new steroid

Monday, February 1st, 2010

SERC woods during wintertime

Liriodendron tulipifera, or tulip poplar, is a common tree in the temperate forests surrounding the Smithsonian Environmental Research Center. Other species include sweetgum, American beech, and southern red oak. Photo: Kirsten Bauer.

Speed is not a word typically associated with trees; they can take centuries to grow. However, a new study to be published the week of Feb. 1 in the Proceedings of the National Academy of Sciences has found evidence that forests in the Eastern United States are growing faster than they have in the past 225 years. The study offers a rare look at how an ecosystem is responding to climate change.
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Climate change may drastically alter Chesapeake Bay, scientists say

Thursday, December 3rd, 2009

Smithsonian researchers Lori Davias and Jenna Malek collect oysters on an intertidal reef in the Chesapeake Bay. It is difficult to predict the effect of climate change on oyster populations because increasing temperatures will likely have at least two opposing effects. On one hand, intertidal oyster populations may be able to expand northward as winter temperatures rise. On the other hand, increasing summer temperatures are likely to worsen the problem of low oxygen concentrations and may reduce the extent or suitability of some subtidal habitat currently used by oysters. At this point, scientists are unable to predict whether the combination of these two factors will result in a net increase or net loss of habitat.  Photo: Sean Fate

Smithsonian researchers Lori Davias and Jenna Malek collect oysters on an intertidal reef in the Chesapeake Bay. It is difficult to predict the effect of climate change on oyster populations because increasing temperatures will likely have at least two opposing effects. On one hand, intertidal oyster populations may be able to expand northward as winter temperatures rise. On the other hand, increasing summer temperatures are likely to worsen the problem of low oxygen concentrations and may reduce the extent or suitability of some subtidal habitat currently used by oysters. At this point, scientists are unable to predict whether the combination of these two factors will result in a net increase or net loss of habitat. Photo: Sean Fate

It is one of the largest and most productive estuaries in the world, yet dramatic changes are in store for the Chesapeake Bay in coming decades if climate change predictions hold true, say a team of scientists from the Smithsonian Environmental Research Center, the University of Maryland, Pennsylvania State University, and other research organizations in a recent paper published in the journal “Estuarine, Coastal and Shelf Science”

Using forecasts of atmospheric carbon dioxide production for the coming century, the scientists predict the water of the Bay will see rising levels of dissolved carbon dioxide and higher water temperatures. As a result, climate change is expected to worsen problems of low dissolved oxygen concentrations in the Chesapeake’s water and cause sea levels to rise.
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Wetlands on the rise, a conversation with biogeochemist Pat Megonigal

Tuesday, December 1st, 2009

Pat Megonigal is a biogeochemist here at the Smithsonian Environmental Research Center (SERC). The following is an interview with him about his recent research.

Smithsonian biogeochemist Pat Megonigal

Smithsonian biogeochemist Pat Megonigal

Climate change scenarios are driven largely by greater concentrations of carbon dioxide in the atmosphere. One common narrative includes faster-rising seas and the potential drowning of coastal regions. You recently published a paper in the Proceedings of the National Academy of Sciences that gives hope to some coastal wetlands. Tell us what you found.
PM: We conducted a study for two years on the Kirkpatrick Marsh, here on the Chesapeake Bay. We discovered that higher levels of atmospheric CO2 actually stimulated the surface elevation of saltwater marshes. The additional CO2 caused them to basically pop up, or rise in elevation, because the plants developed more roots. It’s kind of a silver-lining story.

How did you simulate climate change?
PM: We put out clear open-top chambers that are about two yards in diameter. They allow us to manipulate the atmosphere around a chunk of marsh. Then, in some of the chambers, we pumped in extra CO2; we raised it to a level that will be roughly what the whole world will be exposed to at the end of the century. And then we measured the changes in the soil’s elevation throughout the growing season.

When you think of measuring elevation, mountains come to mind, not soil. How did you measure the soil’s height?

PM: Well, we needed a stable point of elevation reference, so first we drove a steel rod about 20 feet into the ground. Then came the hard part. We had to design a tool that would give us not only precise, but multiple measurements of the soil elevation – both in and outside of our chambers. We came up with an instrument we dubbed the “monster arm.”

Technician Jim Duls measures the soil elevation with the 'monster arm.'

Technician Jim Duls measures the soil elevation with the 'monster arm.'

The monster arm?
PM: The technical name is “surface elevation table.” Basically it’s a long metal bar with 90 fiberglass pins running perpendicular through it. It looks like a big comb, but instead of the teeth being fixed in place, they can move up and down. So by gently placing the monster arm across the chambers we could measure where the top of each pin was in relation to the main crossbar. So if a pin rose 100 millimeters above the bar in April and in August it rose 102 millimeters, the soil elevation increased by two millimeters.

Your study showed that the marsh receiving the extra CO2 rose by an additional 3mm a year. Is that enough to keep pace with the rising sea level?
PM: It should help for a while, but we don’t know how much sea level rise a marsh can handle before it will disappear. We do know that rising sea level is one reason that some marshes in mid-Atlantic and around the world are disappearing right now. Our research indicates that some of these wetlands literally have an organic ability to fight back by building new soil. This is especially true for wetlands with brackish water, like Kirkpatrick Marsh. Saltier coastal wetlands won’t be able to accumulate as much soil because their plants are different and don’t respond to CO2 in the same way. But we’re now conducting a new experiment to look at sea-level rise and its effect on soil elevation. We think the pop-up effect we’ve observed will be even more pronounced when the water level rises. We’ll see!

‘Tidal Freshwater Wetlands’ gives an overlooked ecosystem its due

Tuesday, November 17th, 2009

Tidal Freshwater Wetlands book cover

Tidal Freshwater Wetlands

There are certain obstacles you have to embrace if you are going to edit a book about tidal freshwater wetlands. They include: mud, mosquitoes and leeches. Smithsonian plant ecologist Dennis Whigham has accepted all three and then some.

Whigham, along with colleagues Aat Barendregt from Utrecht University and Andy Baldwin from the University of Maryland, has edited the new book Tidal Freshwater Wetlands. It’s a weighty work containing more than 20 chapters written by more than 40 authors. For the first time ever, they have systematically peeled back the layers of these overlooked coastal ecosystems. The book explores how these wetlands work, the animal and plant life they support, and the threats they face.
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What one marsh tells us about rising CO2

Tuesday, October 27th, 2009

In the world of unassuming marshes, the Kirkpatrick Marsh stands apart. Smithsonian plant physiologist Bert Drake has studied this wetland for more than two decades. It’s located in Maryland, along the Rhode River, a sub-estuary of the Chesapeake Bay. Drake and his colleagues have used this community of grasses and sedges to explore whether plants have the potential to become a carbon source or a carbon sink. Watch the audio slideshow below, for a tour of the field experiment.

You can read more about Drake’s experiment on the Smithsonian Environmental Research Center’s Web site.

Intern Logs: Methanogenesis and nail polish

Tuesday, October 27th, 2009

Q&A with David Gonzalez, 2009 Summer Intern
Major: Evolution, Ecology and Biodiversity
School: University of California-Davis, Class of 2011

Intern David Gonzalez poses with some of his <i>Phragmites australis</i> plants

Intern David Gonzalez poses with some of his Phragmites australis plants


What drew you to the Smithsonian Environmental Research Center?
The big-picture research that the scientists do here interested me, particularly the experiments relating to global climate change. Among other things, scientists of my generation are going to have to understand how climate change will impact organisms. We talk about it a lot in my classes, so it was cool to have the opportunity to have hands-on experience exploring some of these issues as an undergrad.

You were here for ten weeks. What was your research project about?

I worked on a global change project that examined the relationship between microbes in the soil and Common Reed, or Phragmites australis. Through a process called methanogenesis, the microbes produce methane, a powerful greenhouse gas, which the plants help to emit into the atmosphere. Because Phragmites australis is found in wetlands worldwide, it’s important to look at how its methanogenesis rates might be affected by global change. Basically we wanted to see if rising CO2 and nitrogen levels exacerbate the problem of methane emissions. So I spent the summer growing Phragmites australis under conditions of elevated CO2 and nitrogen and then measured the response of the microbes and plants.

Do you feel like you spent your summer being an active scientist?
Half of the summer I felt like a scientist; the other half I felt like a gardener. There were a lot of day-to-day chores like watering the plants, counting them, giving them fertilizer, and weeding them. I had to make sure these plants grew to the best of their ability in the short time we had to grow them.

So you learned about the challenges and realities of doing science?

A lot of things I learned this summer relate to how many little things go into doing scientific research – from going out and buying fuses for a machine when it broke down, to purchasing nail polish at a drug store so we could take a peel from a leaf to count stomatal density.

What exactly did you do with nail polish?
We used it in some pilot studies. You apply nail polish to the leaf, let it dry, put scotch tape on it, and then pull it off. This creates a kind of caste of the leaf that you can put on a microscope slide so you can examine a leaf’s cellular structure. For instance, we can go through and count the guard cells, which lets us figure stomatal density and helps us understand how the leaf is responding to the treatments we applied.

You were in the biogeochemistry lab. Did you interact much with the other labs at SERC?
Yeah, one of the great things about SERC is that you’re surrounded by scientists with all these different areas of expertise. I got a lot of help from the forest ecology lab; they let me use some of their instruments for measuring leaf area. But we also got to go on lab exchanges. I spent a day on the water with the “Crab Lab;” I helped them catch and tag blue crabs. And then I also spent a number of evenings setting up mouse traps in the forest with a friend who was interning in the Terrestrial Ecology Lab. In general, we were encouraged to find out what the other labs were up to, which I often did just by talking with the other interns.

What are the dorms like?
The Green Village is awesome. It has a kitchen, a common area and feels like a nice cozy dorm.

How much independence did you have?
Usually you put in eight hours of work a day; occasionally you work more. After that though, you’re free. We cooked dinners together in the evenings. Some of the interns had a garden with a behemoth of a basil plant – that made for a great pesto party. And then we spent weekends exploring the East Coast. I saw fireworks in Washington, DC, on the Fourth of July; camped in Shenandoah National Park; and swam in the Atlantic Ocean.

SERC's summer interns on a day-trip to the Shenandoah Valley

SERC's summer interns on a day-trip to the Shenandoah Valley


Was it difficult to get around?

A lot of the interns had cars. That was something I was worried about in the beginning, but everybody turned out to be really friendly. If you needed groceries, there were always people going to the grocery store. If you wanted to visit Washington, DC, it was easy to round up people to hit the Smithsonian Museums. The weekend excursions were great.

You’ll graduate in 2011. How do you want to use the knowledge you’ve gained here at SERC?
I’m definitely planning on doing more scientific research – maybe related to climate change, maybe not. Something that I’m very interested in is communicating the importance of environmental science to the general public and to policy makers. I want to be able to convey why it’s important to think about things like climate change, where your food comes from, farming practices, carbon emissions and things like that. That’s sort of my long-term interest – which I hope will go hand-in-hand with my future studies and research experiences.

Visit our web site for more information on internships and fellowships at the Smithsonian Environmental Research Center.