Climate Change

...now browsing by category

 

Why 900 Years of Ancient Oysters Went Missing

Friday, August 29th, 2014

by Kristen Minogue

Piscataway Indians lived on the Rhode River up to colonial times, though anthropologists believe they used the land for temporary campsites, not permanent settlements.

Piscataway Indians lived on the Rhode River up to colonial times, though anthropologists believe they used the land for temporary campsites, not permanent settlements.

For more than 10,000 years, Native Americans hunted and fished in the Chesapeake. Broken pottery, village sites, burial grounds and other artifacts bear witness to their near-continuous presence around the Bay. But one type of artifact—ancient trash piles called shell middens—hasn’t received as much attention. And these tell another important story.

Click to continue »

Marshes: Pollution Sponges of the Future

Thursday, August 21st, 2014

by Melissa Pastore, biology graduate student at Villanova University

Image: Melissa Pastore in a marsh near Delaware Bay. (Credit: Lori Sutter)

Melissa Pastore in a marsh near Delaware Bay.
(Lori Sutter)

What if we could create a giant sponge capable of soaking up nitrogen pollution? It turns out that the Chesapeake Bay, which has experienced a rapid increase in nitrogen pollution from municipal and agricultural sources over the last few decades, already contains a natural version of this sponge: marshes fringing the Bay. But global change—and the nitrogen pollution itself—could change how this natural sponge operates.

Click to continue »

Summer “Marshfest” gets all hands on deck

Thursday, July 24th, 2014

By Sarah Hansen

Experimental chambers and blowers give the marsh a spooky feel on this cloudy morning.

Experimental chambers and blowers give the marsh a spooky feel on this cloudy morning at SERC.

At first encounter, the marsh looks as if it came out of a Heinlein novel. Boxy white robots dot the wetland, igloo-shaped encampments litter the landscape, and thick black tubes snake across the mud—wait, did that one just move? On closer inspection, clusters of human beings appear crouched in the sedge, carefully taking measurements for the annual Global Change Research Wetland (GCREW) Summer Marshfest.

“These two weeks are the most important two weeks of the year for us,” said Smithsonian Environmental Research Center biogeochemist Patrick Megonigal. During Marshfest, senior scientists, postdocs, volunteer citizen scientists, interns, lab techs and visiting students all join forces to collect data for three experiments focused on climate change and nutrient cycling, all managed by Megonigal. Click to continue »

Intern Logs: A Summer Quest
to Understand Winter

Monday, July 21st, 2014

by Dejeanne Doublet

Photo: SERC intern Dejeanne Doublet heads out to sample marsh elder, a plant that in some zones coped surprisingly well with the harsh winter. (Credit Megan Palmer)

SERC intern Dejeanne Doublet heads out to sample marsh elder.
(Megan Palmer)

As we’re knee-deep in the marsh surrounding the Chesapeake Bay, working under the relentless sun during 90-degree weather with 90 percent humidity, sweat dripping down our faces, waving off the summer bugs and trying to collect as much field data as possible, the idea of winter becomes abstract and far-fetched. It’s hard to believe we are out here in the blazing heat of summer studying the effects of this past winter— one of harshest winters this area has endured in many years.

Click to continue »

Getting to the core of carbon in forest soils

Tuesday, July 8th, 2014

By Sarah Hansen

James Biddle, SERC intern, twists a soil augur into the ground to collect a 50 to 100 cm deep soil core.

James Biddle, SERC intern, twists a soil augur into the ground to collect a 50- to 100-centimeter deep soil core.

It’s well-known that carbon dioxide levels are rising in Earth’s atmosphere and that extra CO2 contributes to climate change.  You might also have learned that trees are “carbon sinks” – they take carbon out of the air and store it in their trunks, roots and leaves.  But what about carbon in forest soil?

If you’re not sure, you’re in good company.  “We’re just learning how carbon moves through the forest at the surface, and that’s the most accessible part of the forest,” said Sean McMahon, senior scientist at the Smithsonian Environmental Research Center (SERC).  “Below ground is much more of a mystery.” Click to continue »

Seeking Life in the Mud

Friday, June 13th, 2014

By Sarah Hansen

OLYMPUS DIGITAL CAMERA

Dean Janiak (left) and Ben Rubinoff collect a sample from the Rhode River.

Most of us think of the Chesapeake Bay as a single entity – one big body of water.  But Smithsonian Environmental Research Center (SERC) ecologist Dean Janiak and his intern, Ben Rubinoff, have a more nuanced perspective.  They’ve collected more than 150 samples from eight different habitats within the Bay and along its shoreline that contain mud, sand and lots of tiny animals.

Their ultimate goal: Discover how differences in habitats in the Rhode River (a sub-estuary of the Chesapeake Bay) can change biodiversity among creatures at the bottom of the river, and how those patterns change over time.  If it turns out that some habitats host more diverse animal communities than others, land managers can focus conservation efforts on those areas. Click to continue »

Invasive plant may protect forests from drowning

Thursday, June 12th, 2014

Citizen scientists brave dense swamps to find truth behind Phrag

By Sarah Hansen

JH bands a tree

Jack Hays bands a tree in the marsh.

Sea-level rise triggered by climate change affects coastal ecosystems first.  Marshes and wetlands along the shoreline creep inland, infringing on forest habitats.  Scientists have strong evidence that too much water will gradually drown the trees.  But an invasive reedy plant, known as “Phrag” from its scientific name, Phragmites australis, might be the forests’ unlikely protector, delaying drowning by about a decade.

Invasive Phrag (there is a native subspecies, as well) first came to the U.S. from Europe over 200 years ago.  The native variety coexists peacefully with other plants, but the invader takes over a habitat, choking off other flora.  Only recently, however, has its population growth exploded.   Scientists at the Smithsonian Environmental Research Center are trying to find out whether large Phrag populations in wetlands help or hurt tree growth.  It might seem counterintuitive, but scientists hypothesize that the Phrag is actually helping trees survive as sea level rises.  By removing some of the water, Phrag may prevent trees from drowning.     Click to continue »

The Strange, Controversial Way Plants Trap CO2

Wednesday, June 11th, 2014

by Kristen Minogue

Swamp Rose Mallow surrounded by blades of Schoenoplectus, a sedge in Drake's marsh experiment. (SERC)

Swamp Rose Mallow with blades of Schoenoplectus americanus, a sedge in Drake’s marsh experiment. (SERC)

Plants are among the world’s best carbon sinks, but there’s a side to the plant-CO2 love affair that’s rarely discussed. When carbon dioxide rises, plants cling to it more, releasing less back into the air—and until recently, scientists couldn’t figure out why. With a new paper published June 11 in Global Change Biology, ecologist Bert Drake believes he finally has the answer.

The process is called respiration, and it’s one of the most overlooked parts of the carbon cycle. Unlike photosynthesis, in which plants absorb carbon dioxide and release oxygen, respiration reverses it. And plants respire constantly. Much of the CO2 plants take from the atmosphere for photosynthesis finds its way back via respiration from plants and soil. Which leaves a major question: How much carbon can the world’s ecosystems store as CO2 rises and climate changes?

Click to continue »

Arctic Unguarded: Melting Ice Opens Way
for Invaders

Wednesday, May 28th, 2014

by Kristen Minogue

Arctic sea ice (Patrick Kelley/U.S. Coast Guard)

Arctic sea ice (Patrick Kelley/U.S. Coast Guard)


For the first time in roughly 2 million years, melting Arctic sea ice is connecting the north Pacific and north Atlantic oceans. The new sea routes leave both coasts and Arctic waters vulnerable to a large wave of invasive species—a problem the Arctic has largely avoided until now.

Click to continue »

Intern Logs: Mussels and the Melting Arctic

Thursday, April 3rd, 2014

by Amanda Guthrie, Marine Invasions Lab Intern

Mytilus mussels in Point Judith Marina, Rhode Island. (Photo by Kim Holzer)

Mytilus mussels in Point Judith Marina, Rhode Island. (Kim Holzer)


Imagine after settling down on a place to stay, your home picks up speed and moves without any forewarning, bringing you along with it to a new place. You get off to explore. It seems livable and similar to home, but a few adjustments will be necessary.

This story would be possible — if you were a mussel, a barnacle, or a myriad of other intertidal organisms. Once there, these new arrivals are sometimes able to escape their predators at home and thrive—often at the expense of native species, or the ecosystem as a whole.

Such is the dilemma of Mytilus galloprovincialis, a mussel from the Mediterranean. Mytilus galloprovincialis is native to southern Europe but has branched out to numerous non-native regions around the globe. It is the most prevalent non-native marine species in South Africa. There, it not only competitively displaced native species but also catalyzed the decline of swimming crabs and the increase of whelks.

Click to continue »