Deep subsurface methane hydrate-bearing sediments contain microbial communities that are distinct from shallow marine sediments and hydrate-free environments. DNA evidence suggests that novel bacterial phyla (e.g. Atribacteria) are highly enriched in methane hydrate-bearing sediments. Recent genome assemblies by the Glass group at Georgia Tech are providing insights into the metabolic potential of samples drilled from gas hydrate stability zone 70 mbsf below Hydrate Ridge (IODP Leg 204).
The recently completed resource assessment for ocean current energy (Haas et al. 2013) utilized fairly simplistic analytical methods to estimate the extractable energy from the Gulf Stream System as well as to analyze the relative impacts of large scale energy extraction. This level of analysis can be considered to be accurate to an order of magnitude and only provides an idea on the overall trends of the impacts of extraction. Much higher resolution modeling is required to accurately determine the overall impacts of extraction for both localized and far field effects.
Single-celled marine algae are especially chemically rich, producing toxins that kill fish, marine mammals, and seabirds, contaminate shellfish, and threaten human health. Many predators of these algae – copepods – selectively consume less toxic algae, which in turn sense copepods via an excreted blend of copepod-specific molecules. These algae then become up to 20X more toxic when they sense copepod cues in the open ocean.
Creating sustainable and resilient cities depends on understanding the properties of food, energy, water and other infrastructure networks. Ecological network analysis ENA is a tool that can be used to understand the connections between network structure, material and energy flow, and resilience. ENA is increasingly applied to both understand and design more sustainable and resilient human infrastructure.
Seaweeds create toxic compounds to deter consumers (fish) and poison competitors (corals). However specific fishes resist these toxins, and some corals also are resistant to their effects. These tolerances may be due to unusual microbes in the gut microbiomes of fishes and in coral mucus coverings. GT has an unusual mixture of marine ecologists, chemists and microbiologists to address these issues.
This study seeks to develop a location independent scalable framework for Community based Sustainable Coastal Area Resilience Planning (C-SCARP).
The data-driven framework is adaptable to other locations and/or scales in the future. The proposed C-SCARP framework will make use of an adapted and expanded version of the GoldSET suite of decision support tools that incorporates multi-criteria analysis in a sustainability evaluation framework. Three distinct uses of GoldSET are anticipated:
In coastal areas, data are very sparsely available for flow and wave conditions during storm events due, in part, to the logistical challenge of deploying instruments in such conditions. The questions proposed are centered around the strength and consequences of the flow conditions during storm events and the influence of vegetation on mitigating the effects.
Native microbial communities (microbiomes) of the vertebrate gut exert vital effects on host ecology, physiology, and evolution. This project explores the potential that the gut microbiome of herbivorous fish plays a vital role in biochemically degrading algal toxins consumed by the host fish, and therefore structuring diet choice and ecology. The student will work jointly between the labs of Drs. Mark Hay and Frank Stewart to test this broad hypothesis, likely focusing on the microbiomes of specific coral reef herbivores.
The characterization of sediment biogeochemistry at high spatial and temporal resolution is a necessary step in predicting the overall pathways and extent of hydrocarbon degradation in areas affected during and after an oil spill. However, geochemical data for sediments from deeper environments are scarce, and most studies do not measure the full suite of terminal electron acceptors involved in sediment diagenesis.
Plastic marine debris or the plastisphere impacts marine organisms through ingestion, entanglement, and as a source of toxic chemicals. The plastisphere could also have a major impact on biogeochemical cycles in the oceans. Plastics are transported via major ocean currents to central gyres, where they reside for decadal time scales. The amount of plastic waste is large, exceeding 2 kg/ km2 in central gyres. Even the most recent ocean surveys cannot account for the amount of debris estimated to enter the ocean, with inputs and outputs differing by orders of magnitude.