Using X-ray computed tomography (CT) scanning to characterize the physical characteristics of soil and sediment cores allows scientists to observe and analyze stratigraphy without destroying the integrity of different layers. Microbiologists often work with geologists to characterize the microbial communities in such cores; however, X-rays are known to be destructive...
Marine sediments are one of the largest habitats for microbial life on earth. These microorganisms play critical roles in biogeochemical cycling both within the subsurface and between the sediment and water columns. However, microbial communities in sediments are highly heterogeneous and the factors defining microbial community structure and metabolic function...
In recent decades the habitat of North American beaver (Castor canadensis) has expanded from boreal forests into pan-Arctic tundra ecosystems. It is unknown how the advance of beavers into Arctic watersheds will impact microbial communities responsible for the mineralization of organic matter (OM), which has implications for carbon cycling. To...
Greenhouse gases effects are a leading contributor to climate change; reducing harmful effects of these gases is important for future generations. Worldwide, household consumption makes up seventy-two percent of greenhouse gas emissions, followed by government consumption at ten percent, and investments at eighteen percent (Hertwich, 2009). In order to understand...
The use of ureolytic bacteria for the remediation of contaminated groundwater aquifers by inducing calcium carbonate precipitation is being studied in order to establish a better understanding of the modeling and prediction of how the bacteria will act in situ. This research has pursued the use of various ureolytic bacteria...
Marine sediments contain an abundance of methane that is biologically produced
and plays a significant role in the global carbon cycle. Microbes responsible for the
carbon cycle in marine sediments, and the processes that they carry out, need to be
characterized in order to fully understand the role of this...
Aquifers are an important storage location and source of fresh groundwater. They may become polluted by a number of contaminants including mobile divalent radionuclides such as strontium-90 which is a byproduct of uranium fission. A method for remediating such divalent radionuclides is sequestration through co-precipitation into calcium carbonate. Calcium carbonate...
Microbial-induced calcite (CaCO₃) precipitation (MICP) is a well-known natural phenomenon where microbes precipitate calcite in their environment as a result of metabolic activity. It has recently been of interest as a bioengineered technique to stabilize soils for construction applications. A known metabolic pathway to induce MICP is ureolysis, where introduced...
With rising concentrations of CO₂ in the Earth's atmosphere causing
concern about climate change, many solutions are being presented to
decrease emissions. One of the proposed solutions is to sequester excess
CO₂ in geological formations such as basalt. The deep subsurface is known
to harbor much of the microbial biomass...
Marine sediments are vast sources and reservoirs of methane, a potent greenhouse gas. Most of this methane is anaerobically oxidized by archaea before it can reach the overlying ocean, though the efficiency of this process often depends on methane fluxes and mechanisms of fluid transport. Anaerobic methanotrophic archaea, or ANME,...
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Frederick S. Colwell
Abstract
Marine sediments are vast sources and reservoirs of methane