全球变化知识资源中心

Ten percent of all organic carbon (C-org) absorbed by the ocean each year is stored in seagrass-bearing sediments. The preservation of these carbon stores is considered a vital method to mitigate climate change. Seagrass-bearing sediments have been correlated with sediment geophysical properties yet have not been related to sediment acoustic properties. For this purpose, sediment cores were collected from a Thalassia testudinum seagrass meadow in South Texas, USA, where geophysical, acoustical, and C-org properties were measured. It is hypothesized that when deposits of C-org adsorb onto mineral surfaces and are stored in pore spaces, compliant layers between grain contacts and the formation of an organic-rich suspension reduce sediment stiffness. Results from this seagrass meadow demonstrated a strong correlation between sediment P wave modulus and C-org and show promise toward the development of an in situ ultrasonic sediment probe to more rapidly quantify and monitor seagrass carbon stores.