On the boundaries of fresh and saltwater systems, coastal marshes give rise to diverse, productive ecosystems that act as carbon sinks. Their secret? Freshwater marsh plants receive just the right amount of nutrients and salt from periodic seawater tides to thrive. However, incursions of saltwater into these systems are increasing —often caused by drought and… Read more »
Observed benefits of carbon dioxide enrichment to C3 v. C4 plants appear to reverse after 12 years of treatment.
The Yahara may sound like the name of a vast desert, but it’s actually a 359-square mile watershed in southern Wisconsin. The Yahara Watershed is a mix of urbanized land (including the state capital), productive agriculture land, and a chain of lakes called the Yahara Lakes. Because of its diverse environment, the Yahara provides many… Read more »
Climate change is already impacting polar habitats such as the Arctic tundra, where increasing temperatures are causing permafrost to thaw and exposing soil and organic matter that have been buried for thousands of years. Many scientists predicted that this soil, once exposed, would release a massive amount of sequestered carbon into the atmosphere, contributing to… Read more »
As temperatures rise in many regions around the world, plant species whose ranges were previously limited by low temperature thresholds and intolerance to freezing are increasingly able to expand into new areas and possibly overtake established vegetation regimes. On Hog Island, an undeveloped barrier island off the coast of Virginia, a group of LTER researchers… Read more »
Dan Dillon, Ben Glass-Siegel, Nate Vandiver, and I stood at the edge of a Baltimore road. Cars whizzed by overhead as Glass-Siegel and Vandiver picked their way through dense grass to the river running swiftly beneath the bridge, the blades swishing against their long pants as they blazed a path to the rocky shoreline.
I like to think of Dr. Neil Pederson as a detective. We met in his office at the Harvard Forest Long Term Ecological Research site (HFR-LTER), on the second floor of one of their many beautiful buildings in what feels like a college campus. Multiple sections of tree trunks sit here and there, polished so that the tree rings are clearly visible. Post-it notes and circular stickers mark years of particular interest.
Students gathered at a saltmarsh site in Massachusetts, taking a break from their regular school day routine to remove invasive perennial pepperweed plants from among the bushes and marsh grasses. Part of a suite of programs and teacher workshops aimed at educating local students and adults about marsh ecosystems, this field trip pairs ecological research with real restoration projects.
We stopped at the edge of the river, and Kelsey hopped out with a water quality data sensor to take readings of salinity, temperature, oxygen. Brown water churned around him as he walked slowly across the muddy bottom, silt billowing in the creek channel like clouds of smoke. The data logger is part of a network of such sensors, each taking readings from different parts of the marsh ecosystem.
Kelsey piloted the boat up a smaller creek, stopping in front of a wooden-plank boardwalk leading to a tall eddy covariance flux tower. The tower comprises a series of instruments that take regular measurements that provide a comprehensive picture of carbon dioxide exchange, evaporation, and energy exchange in the coastal marsh. Put simply, the flux towers record the very breathing of the marsh ecosystem.
