Department or Program



Zostera marina, commonly referred to as eelgrass, is a tidal angiosperm found throughout the Gulf of Maine. Eelgrass beds provide a number of ecosystem services such as buffering against coastal erosion, filtering out heavy metals and other pollutants, and sequestering and storing carbon. However, they are vulnerable to disease, climate change, human activities, and invasive species. This project seeks to estimate the amount of carbon stored in eelgrass beds in Casco Bay. Three approximately one-meter long cores were collected from eelgrass beds at three sites in Casco Bay using a percussion hammer to penetrate the silty sands. Additionally, cores were collected from Larrabee cove near Machias. Cores were subsampled every 10cm and analyzed for bulk density, total organic carbon, and grain size. The average carbon density from all three sites in Casco Bay is in agreement with values found globally (Fourqurean at al., 2012) and indicates that eelgrass beds are an effective carbon sink for the region. Estimating carbon storage is limited partially by the accuracy of the eelgrass area maps. Eelgrass beds are difficult to image because they are underwater and ephemeral in nature which makes determining area a challenge in calculating carbon stocks for a region. Spatial differences in carbon density and grain size were also considered.

Level of Access

Restricted: Embargoed [Open Access After Expiration]

First Advisor

Beverly Johnson

Date of Graduation


Degree Name

Bachelor of Arts

Number of Pages


Open Access

Available to all.