Articles
Land and Aquatic Studies: Carbon Stable and Radio Isotope Analysis and More
New writings include articles on the following subjects: Carbon Stable and Radio Isotope Analysis to Identify Methane Sources During a Remedial Action Carbon Isotope Analysis to Confirm Petroleum Natural Attenuation in the Vadose Zone Norfolk Naval Air Base...
read moreDid My Remedial Amendment Produce All That Methane?
Methanogens/Archaea produce methane. They are often the dominant microbes in reduced environments. Methanogenesis is a requisite component of conventional anaerobic bioremediation. If Archaea are not controlled, then in situ remedial actions employing conventional...
read moreStable and Radio Isotope Analysis to Identify Methane Sources During a Remedial Action
Methanogens/Archaea may be dominant microbes in reduced environments, and methanogenesis can be a component of anaerobic bioremediation. If Archaea are not controlled, then in situ remedial actions employing conventional (i.e., no active control of Archaea) amendments...
read moreCoastal Beaufort Sea Alaskan Shelf Organic Carbon Source(s): Strong Spatial Variations
Carbon isotope geochemistry is applied to understand spatial variation in tundra and methane contribution to coastal shallow sediment cycling across the Alaskan Shelf in the Beaufort Sea. This study shows strong spatial variation in the carbon sources that is a...
read moreDissolved Methane in the Beaufort Sea and the Arctic Ocean, 1992-2009; Sources and Atmospheric Flux
Methane concentration and stable carbon isotope ratios measured from ice and ice free waters along the Alaskan Shelf in the Beaufort Sea between 1992 and 2009 show strong spatial variation in flux rates to the atmosphere. Isotope analysis indicated the primary source...
read moreOptical Proxies for Terrestrial Dissolved Organic Matter in Estuaries and Coastal Waters
Dissolved organic matter (DOM) absorbance and fluorescence were used as optical proxies to track terrestrial DOM fluxes through estuaries and coastal waters by comparing models developed for several coastal ecosystems. Key to using these optical properties is validating...
read moreMedically-Derived Iodine-131 as a Tool for Investigating the Fate of Wastewater Nitrogen in Aquatic Environments
Iodine-131 (t1/2 = 8.04 d) is widely used in nuclear medicine, primarily to treat hyperthyroidism and thyroid cancer, with an annual average of 188 treatments per million people in developed countries. The administered dose of Iodine-131 (∼0.1−1 and 4−8 Gbq for...
read moreDeep Sediment-Sourced Methane Contribution to Shallow Sediment Organic Carbon: Atwater Valley, Texas-Louisiana Shelf, Gulf of Mexico
Sediment organic carbon composition and provenance have been extensively studied in the Gulf of Mexico. Generally, inputs of terrestrially-derived organic carbon dominate near shore sediments and decrease with distance offshore where water column phytoplankton...
read morePaleo-Fluid Expulsion Influencing Contouritic Drift Formation on the Chatham Rise, New Zealand
The Chatham Rise is located offshore of New Zealand’s South Island. Vast areas of the Chatham Rise are covered in circular to elliptical seafloor depressions that appear to be forming through a bathymetrically controlled mechanism, as seafloor depressions 2–5 km in...
read moreContribution of Vertical Methane Flux to Shallow Sediment Carbon Pools Across Porangahau Ridge, New Zealand
The majority of coastal sediment carbon cycling studies have focused on contributions from autochthonous photosynthetic marine and allocthonous terrigenous inputs. However, hydrocarbons produced within deep sediment through thermochemical and microbiological...
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