Brian Bergamaschi
Dr. Brian Bergamaschi is a research biogeochemist with the USGS California Water Science Center and adjunct Faculty at California State University Sacramento.
Brian received a Ph.D. in Chemical Oceanography from the University of Washington, in Seattle, WA, where he specialized in analyzing the sources and fates of natural organic material in the environment. His main interests are in understanding processes of carbon and nutrient cycling in aquatic environments and related biogeochemical processes. His particular interest is developing methods to quantify interactions between physical and biogeochemical processes. His research ranges in scale from light-mediated molecular transformations, to tidally driven wetland exchange, to effects of changing continental-scale nutrient fluxes on coastal carbon processes. His current projects largely focus on aquatic biogeochemical processes, aquatic habitat quality and carbon cycling in aquatic systems.
Science and Products
Dissolved organic matter reduces algal accumulation of methylmercury
Seeing the light: the effects of particles, dissolved materials, and temperature on in situ measurements of DOM fluorescence in rivers and streams
In situ optical water-quality sensor networks - Workshop summary report
Tidally driven export of dissolved organic carbon, total mercury, and methylmercury from a mangrove-dominated estuary
Methyl mercury dynamics in a tidal wetland quantified using in situ optical measurements
The aquatic real-time monitoring network; in-situ optical sensors for monitoring the nation's water quality
From deposition to erosion: Spatial and temporal variability of sediment sources, storage, and transport in a small agricultural watershed
Taking the pulse of snowmelt: in situ sensors reveal seasonal, event and diurnal patterns of nitrate and dissolved organic matter variability in an upland forest stream
Coordinating standards and applications for optical water quality sensor networks
How reservoirs alter drinking water quality: Organic matter sources, sinks, and transformations
A method for assessing carbon stocks, carbon sequestration, and greenhouse-gas fluxes in ecosystems of the United States under present conditions and future scenarios
Public Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse-Gas Fluxes in Ecosystems of the United States Under Present Conditions and Future Scenarios
Non-USGS Publications**
**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
- Science
Filter Total Items: 22
- Data
Filter Total Items: 21No Result Found
- Publications
Filter Total Items: 106
Dissolved organic matter reduces algal accumulation of methylmercury
Dissolved organic matter (DOM) significantly decreased accumulation of methylmercury (MeHg) by the diatom Cyclotella meneghiniana in laboratory experiments. Live diatom cells accumulated two to four times more MeHg than dead cells, indicating that accumulation may be partially an energy-requiring process. Methylmercury enrichment in diatoms relative to ambient water was measured by a volume concenAuthorsAllison C. Luengen, Nicholas S. Fisher, Brian A. BergamaschiSeeing the light: the effects of particles, dissolved materials, and temperature on in situ measurements of DOM fluorescence in rivers and streams
Field-deployable sensors designed to continuously measure the fluorescence of colored dissolved organic matter (FDOM) in situ are of growing interest. However, the ability to make FDOM measurements that are comparable across sites and over time requires a clear understanding of how instrument characteristics and environmental conditions affect the measurements. In particular, the effects of waterAuthorsBryan D. Downing, Brian A. Pellerin, Brian A. Bergamaschi, John Franco Saraceno, Tamara E.C. KrausIn situ optical water-quality sensor networks - Workshop summary report
Advanced in situ optical water-quality sensors and new techniques for data analysis hold enormous promise for furthering scientific understanding of aquatic systems. These sensors measure important biogeochemical parameters for long deployments, enabling the capture of data at time scales over which they vary most meaningfully. The high-frequency, real-time water-quality data they generate provideAuthorsBrian A. Pellerin, Brian A. Bergamaschi, Jeffery S. HorsburghTidally driven export of dissolved organic carbon, total mercury, and methylmercury from a mangrove-dominated estuary
The flux of dissolved organic carbon (DOC) from mangrove swamps accounts for 10% of the global terrestrial flux of DOC to coastal oceans. Recent findings of high concentrations of mercury (Hg) and methylmercury (MeHg) in mangroves, in conjunction with the common co-occurrence of DOC and Hg species, have raised concerns that mercury fluxes may also be large. We used a novel approach to estimate expAuthorsBrian A. Bergamaschi, D. P. Krabbenhoft, George Aiken, Eduardo Patino, D.G. Rumbold, William H. OremMethyl mercury dynamics in a tidal wetland quantified using in situ optical measurements
We assessed monomethylmercury (MeHg) dynamics in a tidal wetland over three seasons using a novel method that employs a combination of in situ optical measurements as concentration proxies. MeHg concentrations measured over a single spring tide were extended to a concentration time series using in situ optical measurements. Tidal fluxes were calculated using modeled concentrations and bi-directionAuthorsB.A. Bergamaschi, J.A. Fleck, B.D. Downing, E. Boss, B. Pellerin, N. K. Ganju, D. H. Schoellhamer, A.A. Byington, W.A. Heim, M. Stephenson, R. FujiiThe aquatic real-time monitoring network; in-situ optical sensors for monitoring the nation's water quality
Floods, hurricanes, and longer-term changes in climate and land use can have profound effects on water quality due to shifts in hydrologic flow paths, water residence time, precipitation patterns, connectivity between rivers and uplands, and many other factors. In order to understand and respond to changes in hydrology and water quality, resource managers and policy makers have a need for accurateAuthorsBrian A. Pellerin, Brian A. Bergamaschi, Peter S. Murdoch, Bryan D. Downing, John Franco Saraceno, George R. Aiken, Robert G. StrieglFrom deposition to erosion: Spatial and temporal variability of sediment sources, storage, and transport in a small agricultural watershed
The spatial and temporal variability of sediment sources, storage, and transport were investigated in a small agricultural watershed draining the Coast Ranges and Sacramento Valley in central California. Results of field, laboratory, and historical data analysis in the Willow Slough fluvial system document changes that transformed a transport-limited depositional system to an effective erosion andAuthorsJ.L. Florsheim, B.A. Pellerin, N.H. Oh, N. Ohara, P.A.M. Bachand, Sandra M. Bachand, B.A. Bergamaschi, P.J. Hernes, M.L. KavvasTaking the pulse of snowmelt: in situ sensors reveal seasonal, event and diurnal patterns of nitrate and dissolved organic matter variability in an upland forest stream
Highly resolved time series data are useful to accurately identify the timing, rate, and magnitude of solute transport in streams during hydrologically dynamic periods such as snowmelt. We used in situ optical sensors for nitrate (NO3-) and chromophoric dissolved organic matter fluorescence (FDOM) to measure surface water concentrations at 30 min intervals over the snowmelt period (March 21–May 13AuthorsBrian A. Pellerin, John Franco Saraceno, James B. Shanley, Stephen D. Sebestyen, George R. Aiken, Wilfred M. Wollheim, Brian A. BergamaschiCoordinating standards and applications for optical water quality sensor networks
Joint USGS-CUAHSI Workshop: In Situ Optical Water Quality Sensor Networks; Shepherdstown, West Virginia, 8-10 June 2011; Advanced in situ optical water quality sensors and new techniques for data analysis hold enormous promise for advancing scientific understanding of aquatic systems through measurements of important biogeochemical parameters at the time scales over which they vary. High-frequencyAuthorsB. Bergamaschi, B. PellerinHow reservoirs alter drinking water quality: Organic matter sources, sinks, and transformations
Within reservoirs, production, transformation, and loss of dissolved organic matter (DOM) occur simultaneously. While the balance between production and loss determines whether a reservoir is a net sink or source of DOM, changes in chemical composition are also important because they affect DOM reactivity with respect to disinfection by-product (DBP) formation. The composition of the DOM pool alsoAuthorsTamara E.C. Kraus, Brian A. Bergamaschi, Peter J. Hernes, Daniel H. Doctor, Carol Kendall, Bryan D. Downing, Richard F. LoseeA method for assessing carbon stocks, carbon sequestration, and greenhouse-gas fluxes in ecosystems of the United States under present conditions and future scenarios
he Energy Independence and Security Act of 2007 (EISA), Section 712, mandates the U.S. Department of the Interior to develop a methodology and conduct an assessment of the Nation’s ecosystems, focusing on carbon stocks, carbon sequestration, and emissions of three greenhouse gases (GHGs): carbon dioxide, methane, and nitrous oxide. The major requirements include (1) an assessment of all ecosystemsAuthorsBrian A. Bergamaschi, Richard Bernknopf, David Clow, Dennis Dye, Stephen Faulkner, William Forney, Robert Gleason, Todd Hawbaker, Jinxun Liu, Shu-Guang Liu, Stephen Prisley, Bradley Reed, Matthew Reeves, Matthew Rollins, Benjamin Sleeter, Terry Sohl, Sarah Stackpoole, Stephen Stehman, Robert G. Striegl, Anne Wein, Zhi-Liang ZhuPublic Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse-Gas Fluxes in Ecosystems of the United States Under Present Conditions and Future Scenarios
The Energy Independence and Security Act of 2007 (EISA), Section 712, authorizes the U.S. Department of the Interior to develop a methodology and conduct an assessment of the Nation's ecosystems focusing on carbon stocks, carbon sequestration, and emissions of three greenhouse gases (GHGs): carbon dioxide, methane, and nitrous oxide. The major requirements include (1) an assessment of all ecosysteAuthorsBrian A. Bergamaschi, Richard Bernknopf, David Clow, Dennis Dye, Stephen Faulkner, William Forney, Robert Gleason, Todd Hawbaker, Jinxun Liu, Shu-Guang Liu, Stephen Prisley, Bradley Reed, Matthew Reeves, Matthew Rollins, Benjamin Sleeter, Terry Sohl, Sarah Stackpoole, Stephen Stehman, Robert G. Striegl, Anne Wein, Zhi-Liang ZhuNon-USGS Publications**
Bergamaschi, B.A. and Hedges, J.I. (1995) A Multichambered Apparatus for HF Solvolysis Experiments - Reaction of Cellulose HF Solvolysis Products with Acetic-Acid and Acetic-Anhydride. Carbohydrate Research 267, 115-126. https://doi.org/10.1016/0008-6215(94)00279-OHedges, J.I., Bergamaschi, B.A. and Benner, R. (1994) Comparative Analyses of DOC and DON in Natural Water - Erratum (Vol 41, Pg 121, 1989). Marine Chemistry 46, 407-408. https://doi.org/10.1016/0304-4203(94)90035-3Hedges, J.I., Bergamaschi, B.A. and Benner, R. (1993) Comparative Analyses of DOC and DON in Natural Water. Marine Chemistry 41, 121-134. https://doi.org/10.1016/0304-4203(93)90110-AHopkinson, C., Cifuentes, L., Burdige, D., Fitzwater, S., Hansell, D., Henrichs, S., Kahler, P., Koike, I., Walsh, T. and Bergamaschi, B. (1993) Measurement of Dissolved Organic Carbon and Nitrogen in Natural Waters - DON Subgroup Report. Marine Chemistry 41, 23-36. https://doi.org/10.1016/0304-4203(93)90103-UHedges, J.I. and Bergamaschi, B.A. (1992) Seawater Carbon Measurement. Nature 359, 202-202. https://doi.org/DOI 10.1038/359202a0**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.
- Web Tools
- News