Physical Sciences and Mathematics Commons^™

Iron Geochemistry Across An Estuary-To-Coastal Gradient, Lissett G. Diaz

Honors Theses

Iron is a ubiquitous earth element that participates in biogeochemical processes that occur in marine sediments. Microorganisms utilize iron for many purposes, including cell growth, conserving energy, and for maintaining metabolic activity. In coastal sedimentary settings, understanding the redox reactions involving ferric iron, Fe³⁺, and ferrous iron, Fe²⁺, in its solid phase and pore-water phases, respectively, enable an appreciation of biogeochemical transformations occurring in the coastal zone. In this study, iron concentrations in sediment of ranging permeability were determined at four stations marking an estuary-coast transition zone in Singleton Swash in Myrtle Beach, South Carolina. The …

Dissolved Inorganic Nitrogen Dynamics In Swash Zone Sands Of Long Bay, Sc, Alexis F. Echols

Honors Theses

A key component affecting the biogeochemistry of the sedimentary environment is pore water between grains of sediments. Sedimentary microorganisms are constantly modifying chemical compounds as part of their life functions which are then exchanged between the sediment column and the overlying water column. Dissolved inorganic nitrogen, a major element for life, takes on several forms including nitrate, nitrite, and ammonium which vary in concentration throughout the sediment and with respect to each other. The relative concentrations of these nitrogen species have been previously briefly explored in sandy columns, where redox gradients that control their relative concentrations can be fairly deep …

Characterizing Diatom Biofilms And Their Influence On The Sand Biogeochemistry Of High Energy Beaches, Logan C. Jarrell

Honors Theses

High energy beaches are among the most dynamic ecological settings on Earth. Compared to mudflats, diatoms of high energy beaches have been more neglected in the literature, particularly true of the intertidal biofilms that form and dissipate with nutrient cycling and light intensity over the tidal cycle. Although short lived, the productivity of these biofilms may be critical to the organic-poor sand. Through sediment coring and subsequent analyses of the uppermost sand of three suspected biofilm stations—non-runnel, runnel crest, and runnel trough—along with seemingly bare sand as a control, this study sought to verify the presence of diatom biofilms and …

The Effect Of Oak Leaves On The Leaching Of Trace Metals From Sand, Thomas Elton Goodwin

Honors Theses

Sand is fairly rich in some common trace metals, notably manganese and iron. However, these metals for the most part are in a state which renders them insoluble in water. It is thought that the presence of organic matter (principally leaves) in the water enhances the dissolution of some of these trace metals into the aqueous solution.

This enhancement of dissolution is generally thought to come about in three main ways: (1) The organic matter present lowers the oxygen content of the water, and the metals are reduced into a soluble form, (2) The organic material, some of which is …