Drivers of Sediment Accumulation and Nutrient Burial in Coastal South Carolina Residential Stormwater Detention Ponds

Stormwater detention ponds are widely utilized as control structures to manage runoff waters during storm events. These sediments also represent significant sites of organic carbon and nutrient burial. Here, carbon (C) and nutrient sources and burial rates were determined in 14 residential stormwater detention ponds throughout coastal counties of South Carolina. Bulk sediment accumulation was directly correlated with catchment impervious surface coverage (R2 = 0.90) with sediment accumulation rates ranging from 0.06 to 0.50 cm y-1. These rates of sediment accumulation and subsequent pond volume loss are lower than expected indicating that required maintenance dredging schedules be reassessed. Strong, positive correlations between the Terrestrial Aquatic Ratio (TARHC) biomarker index and sediment accumulation rate (R2 = 0.77), in conjunction with high C:N ratios (16 – 33), suggests that terrestrial biomass drives this sediment accumulation, with relatively minimal contributions from algal derived material. Carbon and nutrient concentrations are consistent between ponds and differences in burial rates were therefore driven by rates of bulk sediment accumulation. Rates of C and nutrient burial (C: 8.7 – 161 g m-2 y-1, N: 0.65 – 6.4 g m-2 y-1, P: 0.238 – 4.13 g m-2 y-1) are similar to those observed in natural lake systems, but lower than those observed in reservoirs or impoundments. Though individual ponds are small in area (930 – 41,000 m2), they are regionally abundant and potentially capable of sequestering C and nutrients at environmentally significant rates

South Carolina Stormwater Detention Ponds: Sediment Accumulation and Nutrient Sequestration

Stormwater detention ponds are prevalent across South Carolina and receive runoff waters carrying both nutrients and sediments. As sediments accumulate in these ponds, water volume is reduced leading to a decrease in runoff retention. Periodic dredging is required to maintain pond function, but dredging is costly and there is little data available to support how often pond dredging is required. It is further unknown how high nutrient loading effects sediment nutrient sequestration and autochthonous production of organic sediment components

Technology transfer from NASA to targeted industries, volume 2

This volume contains the following materials to support Volume 1: (1) Survey of Metal Fabrication Industry in Alabama; (2) Survey of Electronics Manufacturing/Assembly Industry in Alabama; (3) Apparel Modular Manufacturing Simulators; (4) Synopsis of a Stereolithography Project; (5) Transferring Modular Manufacturing Technology to an Apparel Firm; (6) Letters of Support; (7) Fact Sheets; (8) Publications; and (9) One Stop Access to NASA Technology Brochure

Diel investments in metabolite production and consumption in a model microbial system

Organic carbon transfer between surface ocean photosynthetic and heterotrophic microbes is a central but poorly understood process in the global carbon cycle. In a model community in which diatom extracellular release of organic molecules sustained growth of a co-cultured bacterium, we determined quantitative changes in the diatom endometabolome and the bacterial uptake transcriptome over two diel cycles. Of the nuclear magnetic resonance (NMR) peaks in the diatom endometabolites, 38% had diel patterns with noon or mid-afternoon maxima; the remaining either increased (36%) or decreased (26%) through time. Of the genes in the bacterial uptake transcriptome, 94% had a diel pattern with a noon maximum; the remaining decreased over time (6%). Eight diatom endometabolites identified with high confidence were matched to the bacterial genes mediating their utilization. Modeling of these coupled inventories with only diffusion-based phytoplankton extracellular release could not reproduce all the patterns. Addition of active release mechanisms for physiological balance and bacterial recognition significantly improved model performance. Estimates of phytoplankton extracellular release range from only a few percent to nearly half of annual net primary production. Improved understanding of the factors that influence metabolite release and consumption by surface ocean microbes will better constrain this globally significant carbon flux

Supplemental tables for Dissertation of WF Schroer 231022

<p>Supplemental tables for "Metabolite transport and its role in marine microbial interactions", Doctoral Dissertation by William Francis Schroer, University of Georgia, Dept. of Marine Sciences.</p&gt

Fundamentals and applications of solid -fluid equilibrium: Crystallization -based separations

This work is concerned with using solid-fluid equilibrium in separations by crystallization, as well as providing some fundamental understanding of intermolecular forces in solid-fluid equilibrium. The goal is to develop systematic procedures for crystallization-based separations of complex molecules such as chiral molecules and ampholytes, while providing a link between the molecular scale and the plant scale through the use of solid-fluid equilibrium phase diagrams. Major aspects of this project include synthesis of chiral crystallization processes, crystallization of amino acids and ampholytes, crystallization of enantiomers and polymorphs accounting for kinetics and mass transfer effects, and molecular models of solid-fluid equilibrium of single components and mixtures. Process systems engineering for crystallization of these molecules is facilitated by the use of solid-fluid equilibrium phase diagrams. Some of the complexities in the phase diagrams of these molecules, such as polymorphism and compound formation, are related to the phase diagrams of simple molecular models of aromatic hydrocarbons

Functional annotation and importance of marine bacterial transporters of plankton exometabolites

Abstract Metabolite exchange within marine microbial communities transfers carbon and other major elements through global cycles and forms the basis of microbial interactions. Yet lack of gene annotations and concern about the quality of existing ones remain major impediments to revealing currencies of carbon flux. We employed an arrayed mutant library of the marine bacterium Ruegeria pomeroyi DSS-3 to experimentally annotate substrates of organic compound transporter systems, using mutant growth and compound drawdown analyses to link transporters to their cognate substrates. Mutant experiments verified substrates for thirteen R. pomeroyi transporters. Four were previously hypothesized based on gene expression data (taurine, glucose/xylose, isethionate, and cadaverine/putrescine/spermidine); five were previously hypothesized based on homology to experimentally annotated transporters in other bacteria (citrate, glycerol, N-acetylglucosamine, fumarate/malate/succinate, and dimethylsulfoniopropionate); and four had no previous annotations (thymidine, carnitine, cysteate, and 3-hydroxybutyrate). These bring the total number of experimentally-verified organic carbon influx transporters to 18 of 126 in the R. pomeroyi genome. In a longitudinal study of a coastal phytoplankton bloom, expression patterns of the experimentally annotated transporters linked them to different stages of the bloom, and also led to the hypothesis that citrate and 3-hydroxybutyrate were among the most highly available bacterial substrates. Improved functional annotation of the gatekeepers of organic carbon uptake is critical for deciphering carbon flux and fate in microbial ecosystems

The Naval Postgraduate School SCAT++ CubeSat Program

The Naval Postgraduate School (NPS) Small Satellite program provides graduate students with hands-on experience designing, building, and operating satellites. NPS’s first satellite, Petite Amateur Navy Satellite (PANSAT) was deployed through the NASA Hitchhiker program on board STS-9 5 on October 29 , 19 9 8 and operated for several years. As a follow-on project to PANSAT, NPS plans to launch the Spacecraft Architecture and Technology Demonstration Satellite 1 (NPSAT1) sometime in the future. Currently the NPS Small Satellite program is evolving to include CubeSats to further enhance the educational and research opportunities at NPS. As ongoing university, government, and commercial satellite programs are showing, the CubeSat standard is proving to be a unique platform for focused research objectives and engineering design innovation. The first CubeSat to be developed at NPS is called the NPS Solar Cell Array Tester (NPS-SCAT). The overall goal of the project is to gain experience in all phases of CubeSat construction, deployment, and operations by implementing just one of NPSAT1’s many experiments: a solar cell tester. The program is creating a baseline subsystem design for future NPS CubeSats, allowing the NPS Small Satellite program to efficiently use a standard satellite bus for focused research objectives of national interest