Richard L. Smith, Ph.D.
Dr. Richard L. Smith is an Emeritus Microbial Ecologist with expertise in biogeochemistry with the USGS Water Resources Mission Area.
Dr. Richard L. Smith is a microbial ecologist with expertise in biogeochemistry. His research interests have focused upon quantifying in situ rates of microbial processes within aquatic environments and the factors controlling these processes, particularly within the context of the ecosystem. One major study topic has been carbon and nitrogen cycling in groundwater and at the groundwater-surface water interface. These studies have also included characterizing the physiological state of groundwater bacteria, the effect bacteria have upon aquifer geochemistry, developing techniques to assess microbial processes in situ, nitrogen cycling, and bioremediation. Other research areas include biogeochemical processes in freshwater lakes and rivers, agricultural drainages, and in an amictic Antarctic lake.
Education
- BS (Biology) Western Michigan University, 1974
- MS (Biology) Western Michigan University, 1976
- PhD (Microbial Ecology) Michigan State University, 1981
Work Experience
- Postdoc. NRC Postdoctoral Fellow, US Geological Survey, Menlo Park, CA 1981-1983
- Research Hydrologist. USGS, Arvada, CO, 1983-1988
- Research Hydrologist. USGS, Boulder, CO, 1988-2016
- Research Hydrologist. Earth System Processes Division, USGS, Boulder, CO, 2016-2019
- Emeritus Scientist. Earth System Processes Division, USGS, Boulder, CO, 2019-present
Professional affiliations or activities
- American Society for Microbiology
- American Society of Limnology and Oceanography
- American Geophysical Union
- International Society for Microbial Ecology
- Geological Society of America
- International Committee of the Symposium for Subsurface Microbiology, 1999-present
- Executive Committee AGU Biogeosciences Section, 1999-2004
- AGU Award Committee for Excellence in Science Journalism Features, 2000-2004
- AGU Award Committee for Excellence in Science Journalism News, 2000-2004
- USGS Water Resour. Div. Ecology Research Advisor, 1998-2000; Assistant Ecology Research Advisor, 1994-1997
- Co-chair, 1999 International Symposium on Subsurface Microbiology
Honors, awards
- 2020: Geologic Society of America Fellowship
- 2011-2018: USGS, Performance Awards
- 2005: USGS, Superior Service Award
- 2002: USGS, Meritorious Service Award
- 1999 & 2001: USGS, STAR Award
- 1998: AGU Editor’s Citation for Excellence in Refereering
- 1981: National Acad. Sci. Postdoctoral Fellowship
Patents
- U.S. Patent, Small-Scale Hydrogen Oxidizing Denitrifying Bioreactor for Treatment of Nitrate-Contaminated Drinking Water
Science and Products
Determination of the effect of temperature (Q10) on rates of oxygen consumption in surface sediments collected from Ashumet Pond on Cape Cod, MA (2016) Determination of the effect of temperature (Q10) on rates of oxygen consumption in surface sediments collected from Ashumet Pond on Cape Cod, MA (2016)
This data release presents results from a laboratory study designed to measure the effect of temperature on rates of oxygen consumption within lake-bottom surface sediments at 0- to 5-cm depth. Sediment and lake water samples were collected June 8, 2016 from the South site in Ashumet Pond, Cape Cod, MA, where lake water recharges to the aquifer. Samples were shipped to Boulder, CO for...
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of...
Natural gradient, lakebed tracer tests using nitrite in a nitrate-contaminated groundwater discharge zone in Ashumet Pond, Massachusetts Natural gradient, lakebed tracer tests using nitrite in a nitrate-contaminated groundwater discharge zone in Ashumet Pond, Massachusetts
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of...
Filter Total Items: 98
Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate
A previously published field-experimental investigation showed that injection of nitrate in anoxic groundwater that contained aqueous and sediment-bound Fe(II) diminished concentrations of As(V) and As(III) to below drinking-water limits. In the current study, reactive transport modeling confirmed that the observed attenuation was consistent with oxidation of Fe(II) by nitrate, leading...
Authors
Douglas B. Kent, Richard L. Smith, James Jamieson, J.K. Bohlke, Deborah A. Repert, Henning Prommer
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
Groundwater discharge delivering anthropogenic N from surrounding watersheds can impact lake nutrient budgets. However, upgradient groundwater processes and changing dynamics in N biogeochemistry at the groundwater-lake interface are complex and difficult to resolve. In this study, hydrograph variations in a groundwater flow-through lake altered discharge patterns of a wastewater-derived
Authors
Richard L. Smith, Deborah A. Repert, Deborah Stoliker, Douglas B. Kent, Bongkeun Song, Denis R. LeBlanc, Timothy D. McCobb, J.K. Bohlke, Sung Pil Hyun, Hee Sun Moon
Methane and nitrous oxide temporal and spatial variability in two midwestern USA streams containing high nitrate concentrations Methane and nitrous oxide temporal and spatial variability in two midwestern USA streams containing high nitrate concentrations
Concentrations and emissions of greenhouse gases CO2, CH4, and N2O commonly are examined individually in aquatic environments in which each is expected to be relatively important; however, their co-occurrence and dynamic interactions in fluvial settings could provide important information about their controlling biogeochemical processes and potential contributions to global climate...
Authors
Richard L. Smith, J.K. Bohlke
Constraining the oxygen isotopic composition of nitrate produced by nitrification Constraining the oxygen isotopic composition of nitrate produced by nitrification
Measurements of the stable isotope ratios of nitrogen (15N/14N) and oxygen (18O/16O) in nitrate (NO3–) enable identification of sources, dispersal, and fate of natural and contaminant NO3– in aquatic environments. The 18O/16O of NO3– produced by nitrification is often assumed to reflect the proportional contribution of oxygen atom sources, water, and molecular oxygen, in a 2:1 ratio...
Authors
Danielle S. Boshers, Julie Granger, Craig R. Tobias, J.K. Bohlke, Richard L. Smith
Contribution of hurricane-induced sediment resuspension to coastal oxygen dynamics Contribution of hurricane-induced sediment resuspension to coastal oxygen dynamics
Hurricanes passing over the ocean can mix the water column down to great depths and resuspend massive volumes of sediments on the continental shelves. Consequently, organic carbon and reduced inorganic compounds associated with these sediments can be resuspended from anaerobic portions of the seabed and re-exposed to dissolved oxygen (DO) in the water column. This process can drive DO...
Authors
Laura Bianucci, Karthik Balaguru, Richard W. Smith, Ruby Leung, Julia M. Moriarty
Tracing the cycling and fate of the munition, Hexahydro-1,3,5-trinitro-1,3,5-triazine in a simulated sandy coastal marine habitat with a stable isotopic tracer, 15N-[RDX] Tracing the cycling and fate of the munition, Hexahydro-1,3,5-trinitro-1,3,5-triazine in a simulated sandy coastal marine habitat with a stable isotopic tracer, 15N-[RDX]
Coastal marine habitats become contaminated with the munitions constituent, Hexahydro-1,3,5-trinitro-1,3,5-trazine (RDX), via military training, weapon testing and leakage of unexploded ordnance. This study used 15N labeled RDX in simulated aquarium-scale coastal marine habitat containing seawater, sediment, and biota to track removal pathways from surface water including sorption onto
Authors
Thivanka Ariyarathna, Mark Ballentine, Penny Vlahos, Richard W. Smith, Christopher Cooper, J.K. Bohlke, Stephen Fallis, Thomas J. Groshens, Craig R. Tobias
Non-USGS Publications**
Smith, R. L., Kent, D. B., Repert, D. A., and Böhlke, J.K., 2017, Anoxic nitrate reduction coupled with iron oxidation and attenuation of dissolved arsenic and phosphate in a sand and gravel aquifer, Geochim. Cosmochim. Acta, 196:102-120, doi: http//dx.doi.org/10.1016/j.gca.2016.09.025.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Determination of the effect of temperature (Q10) on rates of oxygen consumption in surface sediments collected from Ashumet Pond on Cape Cod, MA (2016) Determination of the effect of temperature (Q10) on rates of oxygen consumption in surface sediments collected from Ashumet Pond on Cape Cod, MA (2016)
This data release presents results from a laboratory study designed to measure the effect of temperature on rates of oxygen consumption within lake-bottom surface sediments at 0- to 5-cm depth. Sediment and lake water samples were collected June 8, 2016 from the South site in Ashumet Pond, Cape Cod, MA, where lake water recharges to the aquifer. Samples were shipped to Boulder, CO for...
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of...
Natural gradient, lakebed tracer tests using nitrite in a nitrate-contaminated groundwater discharge zone in Ashumet Pond, Massachusetts Natural gradient, lakebed tracer tests using nitrite in a nitrate-contaminated groundwater discharge zone in Ashumet Pond, Massachusetts
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of...
Filter Total Items: 98
Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate
A previously published field-experimental investigation showed that injection of nitrate in anoxic groundwater that contained aqueous and sediment-bound Fe(II) diminished concentrations of As(V) and As(III) to below drinking-water limits. In the current study, reactive transport modeling confirmed that the observed attenuation was consistent with oxidation of Fe(II) by nitrate, leading...
Authors
Douglas B. Kent, Richard L. Smith, James Jamieson, J.K. Bohlke, Deborah A. Repert, Henning Prommer
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
Groundwater discharge delivering anthropogenic N from surrounding watersheds can impact lake nutrient budgets. However, upgradient groundwater processes and changing dynamics in N biogeochemistry at the groundwater-lake interface are complex and difficult to resolve. In this study, hydrograph variations in a groundwater flow-through lake altered discharge patterns of a wastewater-derived
Authors
Richard L. Smith, Deborah A. Repert, Deborah Stoliker, Douglas B. Kent, Bongkeun Song, Denis R. LeBlanc, Timothy D. McCobb, J.K. Bohlke, Sung Pil Hyun, Hee Sun Moon
Methane and nitrous oxide temporal and spatial variability in two midwestern USA streams containing high nitrate concentrations Methane and nitrous oxide temporal and spatial variability in two midwestern USA streams containing high nitrate concentrations
Concentrations and emissions of greenhouse gases CO2, CH4, and N2O commonly are examined individually in aquatic environments in which each is expected to be relatively important; however, their co-occurrence and dynamic interactions in fluvial settings could provide important information about their controlling biogeochemical processes and potential contributions to global climate...
Authors
Richard L. Smith, J.K. Bohlke
Constraining the oxygen isotopic composition of nitrate produced by nitrification Constraining the oxygen isotopic composition of nitrate produced by nitrification
Measurements of the stable isotope ratios of nitrogen (15N/14N) and oxygen (18O/16O) in nitrate (NO3–) enable identification of sources, dispersal, and fate of natural and contaminant NO3– in aquatic environments. The 18O/16O of NO3– produced by nitrification is often assumed to reflect the proportional contribution of oxygen atom sources, water, and molecular oxygen, in a 2:1 ratio...
Authors
Danielle S. Boshers, Julie Granger, Craig R. Tobias, J.K. Bohlke, Richard L. Smith
Contribution of hurricane-induced sediment resuspension to coastal oxygen dynamics Contribution of hurricane-induced sediment resuspension to coastal oxygen dynamics
Hurricanes passing over the ocean can mix the water column down to great depths and resuspend massive volumes of sediments on the continental shelves. Consequently, organic carbon and reduced inorganic compounds associated with these sediments can be resuspended from anaerobic portions of the seabed and re-exposed to dissolved oxygen (DO) in the water column. This process can drive DO...
Authors
Laura Bianucci, Karthik Balaguru, Richard W. Smith, Ruby Leung, Julia M. Moriarty
Tracing the cycling and fate of the munition, Hexahydro-1,3,5-trinitro-1,3,5-triazine in a simulated sandy coastal marine habitat with a stable isotopic tracer, 15N-[RDX] Tracing the cycling and fate of the munition, Hexahydro-1,3,5-trinitro-1,3,5-triazine in a simulated sandy coastal marine habitat with a stable isotopic tracer, 15N-[RDX]
Coastal marine habitats become contaminated with the munitions constituent, Hexahydro-1,3,5-trinitro-1,3,5-trazine (RDX), via military training, weapon testing and leakage of unexploded ordnance. This study used 15N labeled RDX in simulated aquarium-scale coastal marine habitat containing seawater, sediment, and biota to track removal pathways from surface water including sorption onto
Authors
Thivanka Ariyarathna, Mark Ballentine, Penny Vlahos, Richard W. Smith, Christopher Cooper, J.K. Bohlke, Stephen Fallis, Thomas J. Groshens, Craig R. Tobias
Non-USGS Publications**
Smith, R. L., Kent, D. B., Repert, D. A., and Böhlke, J.K., 2017, Anoxic nitrate reduction coupled with iron oxidation and attenuation of dissolved arsenic and phosphate in a sand and gravel aquifer, Geochim. Cosmochim. Acta, 196:102-120, doi: http//dx.doi.org/10.1016/j.gca.2016.09.025.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.