Determining Rates and Timing of Silica Fluxes in an Undisturbed New England Salt Marsh
Acadia National Park
In March 2010 Joanna was awarded the LL Bean Acadia National Park Research Fellowship which funds her to quantify the rates and timing of silica fluxes in a relatively undisturbed New England salt marsh. Silica is a critical component of salt marsh vegetation, as it maintains cell structure and provides protection from environmental stresses. Research has identified a strong connection between harmful algal blooms (HABs) in coastal systems and silica-limited waters. Because salt marshes are regulators of Si export to the adjacent estuary, understanding marsh Si processes is a critical next step in wetland biogeochemistry. This study will determine a complete silica budget for a salt marsh in Acadia National Park with the goal of better understanding the role of salt marshes in contributing to the retention and export of Si to coastal systems.
June Sampling where Jo collected above and below-ground biomass from both Spartina alterniflora and Spartina patens marsh grass, and conducted a flume study to measure the silica flux over the marsh. Photos depict the flume study and Jo measuring the flow rate of the tide coming into the flume.
July and August 2010
This summer Jo used the flume to measure fluxes over three complete tidal cycles. She did 18 incubations on the marsh surface each 4 hours long (12 with the dark cores and 6 with the light cores and took 18 cores of the marsh (6 each trip, 3 in each vegetation type) which she will separate into below ground biomass and sediment. She also collected above ground vegetation from 18 plots (9 in each vegetation type). She has collected and analyzed 6 porewater profiles. In addition - she also had a 'shadow' (intern) from the Park Service in the field with her for one day.