Brian Bergamaschi (Former Employee)
Science and Products
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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
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
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
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
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
Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes
The δ13C values of individual trihalomethanes (THM) formed on reaction of chlorine with dissolved organic carbon (DOC) leached from maize (corn; Zea maize L.) and Scirpus acutus(an aquatic bulrush), and with DOC extracted from agricultural drainage waters were determined using purge and trap introduction into a gas chromatograph-combustion-isotope ratio monitoring mass spectrometer. We...
Authors
B.A. Bergamaschi, M.S. Fram, C. Kendall, S. R. Silva, G. R. Aiken, R. Fujii
Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas chromatography-ion trap mass spectrometry Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas chromatography-ion trap mass spectrometry
An analytical method useful for the quantification of a range of pesticides and pesticide degradation products associated with suspended sediments was developed by testing a variety of extraction and cleanup schemes. The final extraction and cleanup methods chosen for use are suitable for the quantification of the listed pesticides using gas chromatography-ion trap mass spectrometry and...
Authors
B.A. Bergamaschi, D.S. Baston, K.L. Crepeau, K.M. Kuivila
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...
Dissolved organic carbon concentrations and compositions, and trihalomethane formation potentials in waters from agricultural peat soils, Sacramento-San Joaquin Delta, California; implications for drinking-water quality Dissolved organic carbon concentrations and compositions, and trihalomethane formation potentials in waters from agricultural peat soils, Sacramento-San Joaquin Delta, California; implications for drinking-water quality
Water exported from the Sacramento-San Joaquin River delta (Delta) is an important drinking-water source for more than 20 million people in California. At times, this water contains elevated concentrations of dissolved organic carbon and bromide, and exceeds the U.S. Environmental Protection Agency's maximum contaminant level for trihalomethanes of 0.100 milligrams per liter if...
Authors
Roger Fujii, Anthony J. Ranalli, George R. Aiken, Brian A. Bergamaschi
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: 111
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
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
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
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
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
Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes
The δ13C values of individual trihalomethanes (THM) formed on reaction of chlorine with dissolved organic carbon (DOC) leached from maize (corn; Zea maize L.) and Scirpus acutus(an aquatic bulrush), and with DOC extracted from agricultural drainage waters were determined using purge and trap introduction into a gas chromatograph-combustion-isotope ratio monitoring mass spectrometer. We...
Authors
B.A. Bergamaschi, M.S. Fram, C. Kendall, S. R. Silva, G. R. Aiken, R. Fujii
Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas chromatography-ion trap mass spectrometry Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas chromatography-ion trap mass spectrometry
An analytical method useful for the quantification of a range of pesticides and pesticide degradation products associated with suspended sediments was developed by testing a variety of extraction and cleanup schemes. The final extraction and cleanup methods chosen for use are suitable for the quantification of the listed pesticides using gas chromatography-ion trap mass spectrometry and...
Authors
B.A. Bergamaschi, D.S. Baston, K.L. Crepeau, K.M. Kuivila
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...
Dissolved organic carbon concentrations and compositions, and trihalomethane formation potentials in waters from agricultural peat soils, Sacramento-San Joaquin Delta, California; implications for drinking-water quality Dissolved organic carbon concentrations and compositions, and trihalomethane formation potentials in waters from agricultural peat soils, Sacramento-San Joaquin Delta, California; implications for drinking-water quality
Water exported from the Sacramento-San Joaquin River delta (Delta) is an important drinking-water source for more than 20 million people in California. At times, this water contains elevated concentrations of dissolved organic carbon and bromide, and exceeds the U.S. Environmental Protection Agency's maximum contaminant level for trihalomethanes of 0.100 milligrams per liter if...
Authors
Roger Fujii, Anthony J. Ranalli, George R. Aiken, Brian A. Bergamaschi
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.