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
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Tidal wetland fluxes of dissolved organic carbon and sediment at Browns Island, California: initial evaluation Tidal wetland fluxes of dissolved organic carbon and sediment at Browns Island, California: initial evaluation
Carbon and sediment fluxes from tidal wetlands are of increasing concern in the Sacramento-San Joaquin River Delta (Delta), because of drinking water issues and habitat restoration efforts. Certain forms of dissolved organic carbon (DOC) react with disinfecting chemicals used to treat drinking water, to form disinfection byproducts (DBPs), some of which are potential carcinogens. The...
Authors
N. K. Ganju, B. Bergamaschi, D. H. Schoellhamer
Preliminary assessment of DOC and THM precursor loads from a freshwater restored wetland, an agricultural field, and a tidal wetland in the Sacramento-San Joaquin River Delta Preliminary assessment of DOC and THM precursor loads from a freshwater restored wetland, an agricultural field, and a tidal wetland in the Sacramento-San Joaquin River Delta
Water exported from the Sacramento-San Joaquin River Delta supplies drinking water to more than 22 million people in California. At certain times of the year, Delta waters contain relatively high concentrations of dissolved organic carbon (DOC) and bromide. During these times, chlorination of Delta water for drinking water disinfection will form disinfection byproducts, such as...
Authors
R. Fujii, B.A. Bergamaschi, N. K. Ganju, J.A. Fleck, K.R. Burow-Fogg, D. Schoellhamer, S. J. Deverel
Covariance of bacterioplankton composition and environmental variables in a temperate delta system Covariance of bacterioplankton composition and environmental variables in a temperate delta system
We examined seasonal and spatial variation in bacterioplankton composition in the Sacramento-San Joaquin River Delta (CA) using terminal restriction fragment length polymorphism (T-RFLP) analysis. Cloned 16S rRNA genes from this system were used for putative identification of taxa dominating the T-RFLP profiles. Both cloning and T-RFLP analysis indicated that Actinobacteria...
Authors
R. Stepanauskas, M.A. Moran, B.A. Bergamaschi, J.T. Hollibaugh
Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon
Specific UV absorbance (SUVA) is defined as the UV absorbance of a water sample at a given wavelength normalized for dissolved organic carbon (DOC) concentration. Our data indicate that SUVA, determined at 254 nm, is strongly correlated with percent aromaticity as determined by 13C NMR for 13 organic matter isolates obtained from a variety of aquatic environments. SUVA, therefore, is...
Authors
J.L. Weishaar, George R. Aiken, Brian A. Bergamaschi, Miranda S. Fram, Roger Fujii, K. Mopper
Dissolved pesticides in the Alamo River and the Salton Sea, California, 1996-97 Dissolved pesticides in the Alamo River and the Salton Sea, California, 1996-97
Water samples were collected from the Alamo River and the Salton Sea, California, in autumn 1996 and late winter/early spring 1997 and analyzed for dissolved pesticides. The two seasons chosen for sampling were during pesticide application periods in the Imperial Valley. Pesticide concentrations were measured in filtered water samples using solid-phase extraction and analyzed by gas...
Authors
Kathryn L. Crepeau, Kathryn Kuivila, Brian A. Bergamaschi
By
Water-quality monitoring and studies of the formation and fate of trihalomethanes during the third injection, storage and recovery test at Lancaster, Antelope Valley, California, March 1998 through April 1999 Water-quality monitoring and studies of the formation and fate of trihalomethanes during the third injection, storage and recovery test at Lancaster, Antelope Valley, California, March 1998 through April 1999
The U.S. Geological Survey, in cooperation with the Los Angeles County Department of Public Works and the Antelope Valley-East Kern Water Agency, conducted three cycles of injection, storage, and recovery tests to evaluate the feasibility of artificially recharging ground water in the Lancaster area of Antelope Valley, California. During the third cycle (March 1998 through April 1999)...
Authors
Miranda S. Fram, Joshua K. Berghouse, Brian A. Bergamaschi, Roger Fujii, Kelly D. Goodwin, Jordan F. Clark
Tannin diagenesis in mangrove leaves from a tropical estuary: A novel molecular approach Tannin diagenesis in mangrove leaves from a tropical estuary: A novel molecular approach
Molecular-level condensed tannin analyses were conducted on a series of mangrove (Rhizophora mangle) leaves at various stages of decomposition in a tropical estuary. Total molecular tannin yields ranged from 0.5% ash-free dry weight (AFDW) in the most highly degraded black leaves (6-7 weeks in the water) up to >7% AFDW in fresh leaves (80% procyanidin (PC) with the remainder being...
Authors
P.J. Hernes, R. Benner, G.L. Cowie, M.A. Goi, B.A. Bergamaschi, J. I. Hedges
Improving water quality in Sweetwater Reservoir, San Diego County, California; sources and mitigation strategies for trihalomethane (THM)-forming carb Improving water quality in Sweetwater Reservoir, San Diego County, California; sources and mitigation strategies for trihalomethane (THM)-forming carb
No abstract available.
Authors
M.S. Fram, B.A. Bergamaschi, Roger Fujii
Pesticides associated with suspended sediments entering San Francisco Bay following the first major storm of water year 1996 Pesticides associated with suspended sediments entering San Francisco Bay following the first major storm of water year 1996
Estuaries receive large quantities of suspended sediments following the first major storm of the water year. The first-flush events transport the majority of suspended sediments in any given year, and because of their relative freshness in the hydrologic system, these sediments may carry a significant amount of the sediment-associated pesticide load transported into estuaries. To...
Authors
Brian A. Bergamaschi, Kathryn Kuivila, Miranda S. Fram
Trihalomethanes formed from natural organic matter isolates: Using isotopic and compositional data to help understand sources Trihalomethanes formed from natural organic matter isolates: Using isotopic and compositional data to help understand sources
Over 20 million people drink water from the Sacramento-San Joaquin Delta despite problematic levels of natural organic matter (NOM) and bromide in Delta water, which can form trihalomethanes (THMs) during the treatment process. It is widely believed that NOM released from Delta peat islands is a substantial contributor to the pool of THM precursors present in Delta waters. Dissolved NOM...
Authors
Brian A. Bergamaschi, Miranda S. Fram, Roger Fujii, George R. Aiken, Carol Kendall, Steven R. Silva
Distributions of uronic acids and O-methyl sugars in sinking and sedimentary particles in two coastal marine environments Distributions of uronic acids and O-methyl sugars in sinking and sedimentary particles in two coastal marine environments
Although recent research has indicated that bacteria may contribute an important fraction of biochemical residues in terrestrial and marine environments, it is difficult for geochemists to identify contributions from these ubiquitous and biochemically diverse organisms. Previous studies have suggested uronic acids and O-methyl sugars may be useful indicators of microbial abundance and...
Authors
Brian A. Bergamaschi, Jeffrey S. Walters, J. I. Hedges
U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 1 (Part A) U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 1 (Part A)
This report contains papers presented at the seventh Technical Meeting of the U.S. Geological Survey (USGS), Toxic Substances Hydrology (Toxics) Program. The meeting was held March 8-12, 1999, in Charleston, South Carolina. Toxics Program Technical Meetings are held periodically to provide a forum for presentation and discussion of results of recent research activities. The objectives of...
Non-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-O
Hedges, 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)90035-3
Hedges, 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-A
Hopkinson, 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-U
Hedges, 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.
Science and Products
Filter Total Items: 22
Filter Total Items: 26
No Result Found
Filter Total Items: 114
Tidal wetland fluxes of dissolved organic carbon and sediment at Browns Island, California: initial evaluation Tidal wetland fluxes of dissolved organic carbon and sediment at Browns Island, California: initial evaluation
Carbon and sediment fluxes from tidal wetlands are of increasing concern in the Sacramento-San Joaquin River Delta (Delta), because of drinking water issues and habitat restoration efforts. Certain forms of dissolved organic carbon (DOC) react with disinfecting chemicals used to treat drinking water, to form disinfection byproducts (DBPs), some of which are potential carcinogens. The...
Authors
N. K. Ganju, B. Bergamaschi, D. H. Schoellhamer
Preliminary assessment of DOC and THM precursor loads from a freshwater restored wetland, an agricultural field, and a tidal wetland in the Sacramento-San Joaquin River Delta Preliminary assessment of DOC and THM precursor loads from a freshwater restored wetland, an agricultural field, and a tidal wetland in the Sacramento-San Joaquin River Delta
Water exported from the Sacramento-San Joaquin River Delta supplies drinking water to more than 22 million people in California. At certain times of the year, Delta waters contain relatively high concentrations of dissolved organic carbon (DOC) and bromide. During these times, chlorination of Delta water for drinking water disinfection will form disinfection byproducts, such as...
Authors
R. Fujii, B.A. Bergamaschi, N. K. Ganju, J.A. Fleck, K.R. Burow-Fogg, D. Schoellhamer, S. J. Deverel
Covariance of bacterioplankton composition and environmental variables in a temperate delta system Covariance of bacterioplankton composition and environmental variables in a temperate delta system
We examined seasonal and spatial variation in bacterioplankton composition in the Sacramento-San Joaquin River Delta (CA) using terminal restriction fragment length polymorphism (T-RFLP) analysis. Cloned 16S rRNA genes from this system were used for putative identification of taxa dominating the T-RFLP profiles. Both cloning and T-RFLP analysis indicated that Actinobacteria...
Authors
R. Stepanauskas, M.A. Moran, B.A. Bergamaschi, J.T. Hollibaugh
Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon
Specific UV absorbance (SUVA) is defined as the UV absorbance of a water sample at a given wavelength normalized for dissolved organic carbon (DOC) concentration. Our data indicate that SUVA, determined at 254 nm, is strongly correlated with percent aromaticity as determined by 13C NMR for 13 organic matter isolates obtained from a variety of aquatic environments. SUVA, therefore, is...
Authors
J.L. Weishaar, George R. Aiken, Brian A. Bergamaschi, Miranda S. Fram, Roger Fujii, K. Mopper
Dissolved pesticides in the Alamo River and the Salton Sea, California, 1996-97 Dissolved pesticides in the Alamo River and the Salton Sea, California, 1996-97
Water samples were collected from the Alamo River and the Salton Sea, California, in autumn 1996 and late winter/early spring 1997 and analyzed for dissolved pesticides. The two seasons chosen for sampling were during pesticide application periods in the Imperial Valley. Pesticide concentrations were measured in filtered water samples using solid-phase extraction and analyzed by gas...
Authors
Kathryn L. Crepeau, Kathryn Kuivila, Brian A. Bergamaschi
By
Water-quality monitoring and studies of the formation and fate of trihalomethanes during the third injection, storage and recovery test at Lancaster, Antelope Valley, California, March 1998 through April 1999 Water-quality monitoring and studies of the formation and fate of trihalomethanes during the third injection, storage and recovery test at Lancaster, Antelope Valley, California, March 1998 through April 1999
The U.S. Geological Survey, in cooperation with the Los Angeles County Department of Public Works and the Antelope Valley-East Kern Water Agency, conducted three cycles of injection, storage, and recovery tests to evaluate the feasibility of artificially recharging ground water in the Lancaster area of Antelope Valley, California. During the third cycle (March 1998 through April 1999)...
Authors
Miranda S. Fram, Joshua K. Berghouse, Brian A. Bergamaschi, Roger Fujii, Kelly D. Goodwin, Jordan F. Clark
Tannin diagenesis in mangrove leaves from a tropical estuary: A novel molecular approach Tannin diagenesis in mangrove leaves from a tropical estuary: A novel molecular approach
Molecular-level condensed tannin analyses were conducted on a series of mangrove (Rhizophora mangle) leaves at various stages of decomposition in a tropical estuary. Total molecular tannin yields ranged from 0.5% ash-free dry weight (AFDW) in the most highly degraded black leaves (6-7 weeks in the water) up to >7% AFDW in fresh leaves (80% procyanidin (PC) with the remainder being...
Authors
P.J. Hernes, R. Benner, G.L. Cowie, M.A. Goi, B.A. Bergamaschi, J. I. Hedges
Improving water quality in Sweetwater Reservoir, San Diego County, California; sources and mitigation strategies for trihalomethane (THM)-forming carb Improving water quality in Sweetwater Reservoir, San Diego County, California; sources and mitigation strategies for trihalomethane (THM)-forming carb
No abstract available.
Authors
M.S. Fram, B.A. Bergamaschi, Roger Fujii
Pesticides associated with suspended sediments entering San Francisco Bay following the first major storm of water year 1996 Pesticides associated with suspended sediments entering San Francisco Bay following the first major storm of water year 1996
Estuaries receive large quantities of suspended sediments following the first major storm of the water year. The first-flush events transport the majority of suspended sediments in any given year, and because of their relative freshness in the hydrologic system, these sediments may carry a significant amount of the sediment-associated pesticide load transported into estuaries. To...
Authors
Brian A. Bergamaschi, Kathryn Kuivila, Miranda S. Fram
Trihalomethanes formed from natural organic matter isolates: Using isotopic and compositional data to help understand sources Trihalomethanes formed from natural organic matter isolates: Using isotopic and compositional data to help understand sources
Over 20 million people drink water from the Sacramento-San Joaquin Delta despite problematic levels of natural organic matter (NOM) and bromide in Delta water, which can form trihalomethanes (THMs) during the treatment process. It is widely believed that NOM released from Delta peat islands is a substantial contributor to the pool of THM precursors present in Delta waters. Dissolved NOM...
Authors
Brian A. Bergamaschi, Miranda S. Fram, Roger Fujii, George R. Aiken, Carol Kendall, Steven R. Silva
Distributions of uronic acids and O-methyl sugars in sinking and sedimentary particles in two coastal marine environments Distributions of uronic acids and O-methyl sugars in sinking and sedimentary particles in two coastal marine environments
Although recent research has indicated that bacteria may contribute an important fraction of biochemical residues in terrestrial and marine environments, it is difficult for geochemists to identify contributions from these ubiquitous and biochemically diverse organisms. Previous studies have suggested uronic acids and O-methyl sugars may be useful indicators of microbial abundance and...
Authors
Brian A. Bergamaschi, Jeffrey S. Walters, J. I. Hedges
U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 1 (Part A) U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 1 (Part A)
This report contains papers presented at the seventh Technical Meeting of the U.S. Geological Survey (USGS), Toxic Substances Hydrology (Toxics) Program. The meeting was held March 8-12, 1999, in Charleston, South Carolina. Toxics Program Technical Meetings are held periodically to provide a forum for presentation and discussion of results of recent research activities. The objectives of...
Non-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-O
Hedges, 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)90035-3
Hedges, 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-A
Hopkinson, 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-U
Hedges, 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.