A conceptual model of how the ecosystems interact by natural
and anthropogenic processes guides the research. The salt marshes, Q-2 in
the conceptual model above, interact directly with the water column by exchanging
water, nutrients, and carbon, and by hosting a variety of organisms that
interact with each other and with the marshes in various ways. One finding
that is particularly interesting is the connection between the primary productivity
of Spartina alterniflora marshes and the mean high water level (see
figure below). One of our major goals is to determine if anomalies in sea
level affect the  productivity of the marsh plants at Plum Island Sound. At North Inlet
we have observed that interannual changes in mean sea level have a large
effect on primary production. The Plum Island
Sound study has shown that this phenomenon is indeed common and synchronous
across estuaries, at least regionally. This is important because changes
in production and sea level could have broad-scale effects, such as an impact
on fisheries or coastal water quality. However, the effect of mean sea level
on marsh productivity is positive only if the elevation of the marsh surface
is super-optimal for the vegetation. |
As part of a Long Term Ecological Research project headed by Anne Giblin
(Ecosystems Center, MBL, Woods Hole), my lab is developing a long-term data
base that describes the ecology of intertidal marshes around the Plum Island
Estuary, in Massachusetts.. We want to understand the functional interrelationships
between the intertidal wetlands and the estuary proper, and we are especially
interested in how these marshes will respond to sea-level rise.. We are
monitoring production, sedimentation, and sediment chemistry in control
and experimentally fertilized sites to contrast with those already in place
in North Inlet. We also are examining the changes in biogeochemical properties
of sediments along the estuarine salinity gradient. Photos above left are
from Plum Island.