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Diazotrophic Community Structure and Function in Two Successional Stages of Biological Soil Crusts from the Colorado Plateau and Chihuahuan Desert
ABSTRACT The objective of this study was to characterize the community structure and activity of N2-fixing microorganisms in mature and poorly developed biological soil crusts from both the ColoradoExpand
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Molecular and cellular fundamentals of aerobic cometabolism of trichloroethylene
Cometabolism recognizes that microorganisms can transform non-growth-supporting substrates. The term "cometabolism'' was first introduced over 30 years ago and has been redefined, criticized, andExpand
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Changes in Nitrogen-Fixing and Ammonia-Oxidizing Bacterial Communities in Soil of a Mixed Conifer Forest after Wildfire
ABSTRACT This study was undertaken to examine the effects of forest fire on two important groups of N-cycling bacteria in soil, the nitrogen-fixing and ammonia-oxidizing bacteria. Sequence andExpand
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Response and resilience of soil biocrust bacterial communities to chronic physical disturbance in arid shrublands
The impact of 10 years of annual foot trampling on soil biocrusts was examined in replicated field experiments at three cold desert sites of the Colorado Plateau, USA. Trampling detrimentallyExpand
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Response of Biological Soil Crust Diazotrophs to Season, Altered Summer Precipitation, and Year-Round Increased Temperature in an Arid Grassland of the Colorado Plateau, USA
Biological soil crusts (biocrusts), which supply significant amounts of fixed nitrogen into terrestrial ecosystems worldwide (∼33 Tg y−1), are likely to respond to changes in temperature andExpand
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Sequestration and remobilization of radioiodine (129I) by soil organic matter and possible consequences of the remedial action at Savannah River Site.
In order to investigate the distributions and speciation of (129)I (and (127)I) in a contaminated F-Area groundwater plume of the Savannah River Site that cannot be explained by simple transportExpand
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Nitrogen Fertilization Has a Stronger Effect on Soil Nitrogen-Fixing Bacterial Communities than Elevated Atmospheric CO2
ABSTRACT Biological nitrogen fixation is the primary supply of N to most ecosystems, yet there is considerable uncertainty about how N-fixing bacteria will respond to global change factors such asExpand
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Concentration-dependent mobility, retardation, and speciation of iodine in surface sediment from the Savannah River Site.
Iodine occurs in multiple oxidation states in aquatic systems in the form of organic and inorganic species. This feature leads to complex biogeochemical cycling of stable iodine and its long-livedExpand
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Organo-iodine formation in soils and aquifer sediments at ambient concentrations.
One of the key risk drivers at radioactive waste disposal facilities is radioiodine, especially 129I. As iodine mobility varies greatly with iodine speciation, experiments with 129I-contaminatedExpand
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Two Distinct Monooxygenases for Alkane Oxidation inNocardioides sp. Strain CF8
ABSTRACT Alkane monooxygenases in Nocardioides sp. strain CF8 were examined at the physiological and genetic levels. Strain CF8 can utilize alkanes ranging in chain length from C2 to C16. ButaneExpand
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