Biogeochemistry of the Sediments of the Pamlico and Neuse River Estuaries, North Carolina

摘要

The report is a survey of the composition, distribution, and sources of surface sediments in the Pamlico and Neuse River Estuaries. The interstitial (pore) waters of the sediments were also studied to estimate the decomposition stoichiometry of organic matter and the diffusive flux of NH, FRP(filterable reactive phosphorus), SO, Si, DIC(dissolved inorganic carbon), and Cl. The sediments of the two estuaries were quite similar. Mud deposits covered 90% of the area of both, and the remainder was sandy sediments near shore or upriver of the transition zone. Data indicate that deposition of estuarine phytoplankton carbon governs the organic chemistry of the top meter of sediments in the lower two thirds of the esturaries, while in lower-salinity upriver areas, freshwater carbon is evident. Only about half of the calculated N and P of phytoplankton sedimentation is returned to the water column, thus storage and recycling of nutrients within the sediments is occurring.