Scientists at the National Science Foundation (NSF)'s newest Long-Term Ecological Research (LTER) site, Plum Island Sound in Massachusetts, hope to discover how productivity in estuaries -- places where rivers meet the sea -- is affected by changes in land cover, climate and sea level.
The Plum Island award, made by NSF's divisions of environmental biology and ocean sciences, is for $3,780,000 over six years. Researchers aim to discover how these factors have impacted three estuaries along the U.S. East Coast: Plum Island; Wells, Maine; and North Inlet, South Carolina.
Plum Island Sound is the most recent addition to a network of 21 LTER sites supported by NSF. Of these 21 sites, 19 are scattered across North America, and two sites are located in Antarctica.
Ecosystems at the land-sea interface, like Plum Island, are among the most productive on earth because of the material they receive from bordering terrestrial and oceanic systems. "But human activities in rivers and watersheds have enormously altered such estuarine ecosystems through inputs of materials such as water, sediments, nutrients, and organic matter," says Scott Collins, director of NSF's LTER program. "An important but neglected link between land and near-shore coastal waters is the input of these materials. Research through the Plum Island site should tell us a lot about how food web dynamics in estuaries have been altered."
An estuary is a mosaic of habitats, including open water, tidal creekbank marshes and marsh ponds, explains scientist Chuck Hopkinson of the Marine Biological Laboratory in Woods Hole, Massachusetts, principal investigator on the Plum Island LTER project. "Getting a large-scale view of an estuary is important. On a small scale, a section of estuary may appear healthy, but a large-scale look may show that it is deteriorating."
Adds Philip Taylor, director of NSF's biological oceanography program, "The Plum Island project addresses the question of how ecosystems in a region respond to large-scale disturbances, such as long-term sea level rise. In this case, the region is the U.S. East Coast." Scientists working on the project also hope to discover how the biota of different biogeographic provinces are affected by similar nutrient inputs, freshwater supply, and availability of organic matter.
"Despite an awareness that large-scale, long-term changes are happening in estuaries," explains Taylor, "we don't fully understand the consequences of activities like damming of rivers, land-use changes and removal of floodplains."
Often, human influences on these systems result in opposing effects. Clearing of land, for example, increases sediment in a drainage basin, while damming decreases sediment discharge. Climate variability and long-term patterns of climate change can also have immense effects on the timing, magnitude and nature of material inputs. Infrequent storms can accomplish in days what would normally occur over decades.
Through research at the Plum Island Sound LTER site, scientists hope to soon have a better, broader view of estuarine dynamics.
Program contact:
Scott Collins, DEB (703) 306-1479, scollins@nsf.gov
Phil Taylor, OCE (703) 306-1587, prtaylor@nsf.gov