Brian Bergamaschi (Former Employee)
Science and Products
Filter Total Items: 22
Filter Total Items: 26
No Result Found
Filter Total Items: 111
Mississippi River nitrate loads from high frequency sensor measurements and regression-based load estimation Mississippi River nitrate loads from high frequency sensor measurements and regression-based load estimation
Accurately quantifying nitrate (NO3–) loading from the Mississippi River is important for predicting summer hypoxia in the Gulf of Mexico and targeting nutrient reduction within the basin. Loads have historically been modeled with regression-based techniques, but recent advances with high frequency NO3– sensors allowed us to evaluate model performance relative to measured loads in the...
Authors
Brian A. Pellerin, Brian A. Bergamaschi, Robert J. Gilliom, Charles G. Crawford, John Franco Saraceno, C. Paul Frederick, Bryan D. Downing, Jennifer C. Murphy
Baseline and projected future carbon storage and greenhouse-gas fluxes in ecosystems of the eastern United States Baseline and projected future carbon storage and greenhouse-gas fluxes in ecosystems of the eastern United States
This assessment was conducted to fulfill the requirements of section 712 of the Energy Independence and Security Act of 2007 and to conduct a comprehensive national assessment of storage and flux (flow) of carbon and the fluxes of other greenhouse gases in ecosystems of the Eastern United States. These carbon and greenhouse gas variables were examined for major terrestrial ecosystems...
Concurrent photolytic degradation of aqueous methylmercury and dissolved organic matter Concurrent photolytic degradation of aqueous methylmercury and dissolved organic matter
Monomethyl mercury (MeHg) is a potent neurotoxin that threatens ecosystem viability and human health. In aquatic systems, the photolytic degradation of MeHg (photodemethylation) is an important component of the MeHg cycle. Dissolved organic matter (DOM) is also affected by exposure to solar radiation (light exposure) leading to changes in DOM composition that can affect its role in...
Authors
Jacob A. Fleck, Gary W. Gill, Brian A. Bergamaschi, Tamara E.C. Kraus, Bryan D. Downing, Charles N. Alpers
Optical sensors for water quality Optical sensors for water quality
Shifts in land use, population, and climate have altered hydrologic systems in the United States in ways that affect water quality and ecosystem function. Water diversions, detention in reservoirs, increased channelization, and changes in rainfall and snowmelt are major causes, but there are also more subtle causes such as changes in soil temperature, atmospheric deposition, and shifting
Authors
Brian A. Pellerin, Brian A. Bergamaschi
DOM composition in an agricultural watershed: assessing patterns and variability in the context of spatial scales DOM composition in an agricultural watershed: assessing patterns and variability in the context of spatial scales
Willow Slough, a seasonally irrigated agricultural watershed in the Sacramento River valley, California, was sampled synoptically in order to investigate the extent to which dissolved organic carbon (DOC) concentrations and compositions from throughout the catchment are represented at the mouth. DOC concentrations ranged from 1.8 to 13.9 mg L−1, with the lowest values in headwater 1st...
Authors
Peter J. Hernes, Robert G. M. Spencer, Rachel Y. Dyda, Brian A. Pellerin, Philip A. M. Bachand, Brian A. Bergamaschi
Groundwater contributions of flow, nitrate, and dissolved organic carbon to the lower San Joaquin River, California, 2006-08 Groundwater contributions of flow, nitrate, and dissolved organic carbon to the lower San Joaquin River, California, 2006-08
The influence of groundwater on surface-water quality in the San Joaquin River, California, was examined for a 59-mile reach from the confluence with Salt Slough to Vernalis. The primary objective of this study was to quantify the rate of groundwater discharged to the lower San Joaquin River and the contribution of nitrate and dissolved organic carbon concentrations to the river...
Authors
Celia Zamora, Randy A. Dahlgren, Charles R. Kratzer, Bryan D. Downing, Ann D. Russell, Peter D. Dileanis, Brian A. Bergamaschi, Steven P. Phillips
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
Mississippi River nitrate loads from high frequency sensor measurements and regression-based load estimation Mississippi River nitrate loads from high frequency sensor measurements and regression-based load estimation
Accurately quantifying nitrate (NO3–) loading from the Mississippi River is important for predicting summer hypoxia in the Gulf of Mexico and targeting nutrient reduction within the basin. Loads have historically been modeled with regression-based techniques, but recent advances with high frequency NO3– sensors allowed us to evaluate model performance relative to measured loads in the...
Authors
Brian A. Pellerin, Brian A. Bergamaschi, Robert J. Gilliom, Charles G. Crawford, John Franco Saraceno, C. Paul Frederick, Bryan D. Downing, Jennifer C. Murphy
Baseline and projected future carbon storage and greenhouse-gas fluxes in ecosystems of the eastern United States Baseline and projected future carbon storage and greenhouse-gas fluxes in ecosystems of the eastern United States
This assessment was conducted to fulfill the requirements of section 712 of the Energy Independence and Security Act of 2007 and to conduct a comprehensive national assessment of storage and flux (flow) of carbon and the fluxes of other greenhouse gases in ecosystems of the Eastern United States. These carbon and greenhouse gas variables were examined for major terrestrial ecosystems...
Concurrent photolytic degradation of aqueous methylmercury and dissolved organic matter Concurrent photolytic degradation of aqueous methylmercury and dissolved organic matter
Monomethyl mercury (MeHg) is a potent neurotoxin that threatens ecosystem viability and human health. In aquatic systems, the photolytic degradation of MeHg (photodemethylation) is an important component of the MeHg cycle. Dissolved organic matter (DOM) is also affected by exposure to solar radiation (light exposure) leading to changes in DOM composition that can affect its role in...
Authors
Jacob A. Fleck, Gary W. Gill, Brian A. Bergamaschi, Tamara E.C. Kraus, Bryan D. Downing, Charles N. Alpers
Optical sensors for water quality Optical sensors for water quality
Shifts in land use, population, and climate have altered hydrologic systems in the United States in ways that affect water quality and ecosystem function. Water diversions, detention in reservoirs, increased channelization, and changes in rainfall and snowmelt are major causes, but there are also more subtle causes such as changes in soil temperature, atmospheric deposition, and shifting
Authors
Brian A. Pellerin, Brian A. Bergamaschi
DOM composition in an agricultural watershed: assessing patterns and variability in the context of spatial scales DOM composition in an agricultural watershed: assessing patterns and variability in the context of spatial scales
Willow Slough, a seasonally irrigated agricultural watershed in the Sacramento River valley, California, was sampled synoptically in order to investigate the extent to which dissolved organic carbon (DOC) concentrations and compositions from throughout the catchment are represented at the mouth. DOC concentrations ranged from 1.8 to 13.9 mg L−1, with the lowest values in headwater 1st...
Authors
Peter J. Hernes, Robert G. M. Spencer, Rachel Y. Dyda, Brian A. Pellerin, Philip A. M. Bachand, Brian A. Bergamaschi
Groundwater contributions of flow, nitrate, and dissolved organic carbon to the lower San Joaquin River, California, 2006-08 Groundwater contributions of flow, nitrate, and dissolved organic carbon to the lower San Joaquin River, California, 2006-08
The influence of groundwater on surface-water quality in the San Joaquin River, California, was examined for a 59-mile reach from the confluence with Salt Slough to Vernalis. The primary objective of this study was to quantify the rate of groundwater discharged to the lower San Joaquin River and the contribution of nitrate and dissolved organic carbon concentrations to the river...
Authors
Celia Zamora, Randy A. Dahlgren, Charles R. Kratzer, Bryan D. Downing, Ann D. Russell, Peter D. Dileanis, Brian A. Bergamaschi, Steven P. Phillips
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.