Unit Affiliation: Marine and Polar Geophysics, Lamont-Doherty Earth Observatory (LDEO)
During this project, how microplastics accumulate within sediments along the eastern U.S. coastal setting will be investigated. This study will be the first of its kind to use fluorescent microscopy techniques to quantify plastic deposition over time in sediment cores from the Hudson River and Long Island Sound to farther offshore. Results will provide information about how microplastics get transported from their sources to the ocean and how fast they accumulate in sediments. With a better understanding of microplastic accumulation, more reliable computer models can be constructed to predict how sediment layers are generated as well as the future distribution of microplastics and their impact in the coastal environment. This project will promote the training and professional growth of junior scientists and graduate students from Columbia University as well as nearby high school students.
This study investigates the spatio-temporal variability microplastics accumulating in sediments within a transect of cores from the Hudson River, Long Island Sound and nearshore ocean within 50 km of the coast. Microplastics will be identified through fluorescence microscopy after staining with a lipid soluble fluorescent dye. Chronostratigraphic data already available on these cores will be used to constrain age estimates and allow quantitative comparison of microplastic accumulation during the last century. In particular, the following hypotheses will be tested: a) vertically-integrated concentrations of microplastics differ for samples collected nearby large urban environments (e.g., cities) vs. those collected in open ocean, with concentrations increasing as we get closer to cities; and b) microplastic concentrations began accumulating around 1950 and have been increasing at an exponential rate over the past few decades. Results from this project will provide basic data needed to understand natural processes that control the transport and distribution of microplastic particulates over time and to develop models that predict their future microplastic concentrations in the oceanic sedimentary environment.