By Philip Kiefer

Even healthy trees in the forest, like this tulip poplar, might be producing methane.

Until a decade ago, scientists believed forests were ravenous consumers of methane, a potent greenhouse gas. But we’re discovering that the story is more complicated. It turns out that while forest soils absorb methane, trees might actually release the gas. The problem is, no one is sure how much methane the trees are producing, or why they’re producing it at all.

“We’ve seen anything from 5 percent to 100 percent offset,” says Paul Brewer, a postdoctoral fellow at the Smithsonian Environmental Research Center (SERC).  That’s an enormous amount of uncertainty: The forest could be consuming as much methane as we once thought (almost all of it), or barely any at all.

SERC Intern Helps Pin Down Numbers

Maddie Peterson, an intern working for Brewer at the SERC Biogeochemistry Lab, is spending her summer trying to pin these numbers down.

She’s working to solve two questions. First, how much methane is an average tree releasing? And second, why is it doing so at all?

“The big question,” says Peterson, “is whether the trees are acting as straws” – siphoning methane up from deep in the earth – “or incubators” – cradling methane-producing bacteria in their trunks. Answering these questions will help scientists understand how methane moves in and out of the atmosphere, which is critical for predicting the course of climate change. Click to continue »

By Philip Kiefer

Maya Bhalla-Ladd, who is beginning her second summer as an intern at the Smithsonian Environmental Research Center (SERC), didn’t think growing up that she would be a scientist. “In high school, I spent all my time on ballet,” she says. “I danced professionally. I lived on my own in New York.”

But when health problems forced her to turn away from ballet, she found herself drawn to the ocean. “I remember going to the aquarium as a kid and watching the rays,” she says. “The way they move is very naturally beautiful. So when I stopped being able to dance, I wanted to spend the rest of my life preserving that kind of natural beauty for other people to enjoy.”

Maya with a hand-crafted temperature sensor! (Maya Bhalla-Ladd/SERC)

Maya spent last summer at SERC’s Global Change Research Wetland (GCREW), investigating how climate change could affect photosynthesis in marsh plants. While there, she became fascinated with a tool used to measure photosynthesis in leaves. The tool seals a single leaf in a chamber and exposes it to light, causing the leaf to begin photosynthesis. It can then measure the precise gas composition of the chamber as the plant produces sugar. In effect, it can watch the plant breathe.

“I think that the instrumentation that enables science is so cool, and that we don’t spend enough time thinking about it,” Maya says. Click to continue »