Functional Wetland Shifts through Changes in Plant Community, Nutrient dynamics, Blue Carbon Storage and Invasive Species ... - What Can we Learn for the Future?

Abstract:

Coastal tidal wetlands are particularly valuable for their biodiversity, nursery habitat for fisheries, water purification, carbon sequestration, paleoclimatic archives, and heavy metal capture. Yet they are threatened by invasive species, nitrogen pollution, and sea level rise. It is vital for coastal wetlands to retain both their structure and function despite these challenges. To help us understand how the marshes have accumulated over millennia, and how best to preserve their resilience in the future, we have examined tidal marsh cores from the Hudson River Estuary and Long Island Sound. These include lower Hudson marshes such as Iona, as well as North Sikorsky and Wheeler Marsh in coastal Connecticut. We utilize multi-proxy methods to examine organic and inorganic components of the sediment, including loss-on-ignition, pollen and spore analysis, macrofossil analysis, X-ray fluorescence spectroscopy, and stable isotope ratio measurements of C and N. We compare results from different marshes through recent centuries and the relationship of these shifts to natural variability and human-induced change. We will also compare the marshes' pollution history to that of sediment archives in Long Island Sound. This project provided place- and project-based learning through NASA/Goddard Institute for Space Studies Climate Change Research Initiative and Lamont-Doherty's Secondary School Field Research Program. Many of the field samples were collected by young investigators from schools in New York City and the Hudson Valley.