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
Remote Sensing of Mercury Pollution in South San Francisco Bay
Biogeochemistry Group
Sampling Locations for the Water Quality of San Francisco Bay Project
Sampling Methods for the Water Quality of San Francisco Bay Project
Research Vessel David H. Peterson
Assessing Sediment Nutrient Storage and Release in California's Sacramento-San Joaquin Delta
Evaluating the effects of wastewater-derived nutrients on phytoplankton abundance and community structure in the San Francisco Estuary and Delta
Water Quality of San Francisco Bay Research and Monitoring Project
Modeling Nitrogen Reduction Benefit to Invasive Aquatic Vegetation vs. Native Phytoplankton
Creating a Model to Predict Future Carbon Levels in Tidally-driven Marshes
NASA-USGS National Blue Carbon Monitoring System
Trends in Dissolved Organic Carbon (DOC) in the Sacramento-San Joaquin Delta
Above-water hyperspectral field spectroscopy measurements at Franks Tract in the Sacramento-San Joaquin Delta, California
Assessing spatial variability of nutrients, phytoplankton, and related water-quality constituents in the San Francisco Bay, California: 2021-2022 High-resolution mapping surveys
Water quality, nutrient, and phytoplankton data from Franks Tract, Mildred Island, and neighboring channels in the California Sacramento-San Joaquin Delta: 2022 and 2023 High-resolution mapping surveys
KdPAR and surface water-quality data collected in the Sacramento-San Joaquin River Delta in 2013 and 2014
Assessing spatial variability of nutrients, phytoplankton and related water-quality constituents in the California Sacramento-San Joaquin Delta at the landscape scale: 2020-2021 High-resolution mapping surveys
Assessing spatial variability of nutrients, phytoplankton, and related water quality constituents in the California Sacramento-San Joaquin Delta during treated wastewater effluent holds: August and September 2019 high resolution mapping surveys
Phytoplankton Species Composition and Abundance in the Sacramento-San Joaquin River Delta: Microscopic Enumeration of USGS Samples, beginning in 2016 (ver. 1.1, December 2023)
Assessing spatial variability of nutrients, phytoplankton, and related water quality constituents in the California Sacramento-San Joaquin Delta related to the 2015 installation of the False River Emergency Drought Barrier: 2015 and 2016 high-resolution m
High resolution and discrete temporal and spatial water-quality measurements in support of modeling mercury and methylmercury concentrations in surface waters of the Sacramento-San Joaquin River Delta
Concentration Data for 12 Elements of Concern Used in the Development of Surrogate Models for Estimating Elemental Concentrations in Surface Water of Three Hydrologic Basins (Delaware River, Illinois River and Upper Colorado River)
Tidal hydrologic and constitutent loads from First Mallard Water Quality Station in the Rush Ranch Marsh Complex of the San Francisco Bay Estuarine Research Reserve (SFBNERR) 2016-2018
Characterization of water residence time, nutrients, phytoplankton and related water quality constituents in the Cache Slough Complex of the California Sacramento-San Joaquin Delta in 2017 and 2018
Assessing spatial variability of nutrients, phytoplankton, and related water-quality constituents in the California Sacramento–San Joaquin Delta at the landscape scale—2018 high resolution mapping surveys
Evaluation and refinement of chlorophyll-a algorithms for high-biomass blooms in San Francisco Bay (USA)
Physics to fish—Understanding the factors that create and sustain native fish habitat in the San Francisco Estuary
A simple approach to modeling light attenuation in the Sacramento-San Joaquin Delta using commonly available data
A novel boat-based field application of a high-frequency conductometric ammonium analyzer to characterize spatial variation in aquatic ecosystems
Field techniques for fluorescence measurements targeting dissolved organic matter, hydrocarbons, and wastewater in environmental waters: Principles and guidelines for instrument selection, operation and maintenance, quality assurance, and data reporting
Increased salinity decreases annual gross primary productivity at a Northern California brackish tidal marsh
Field techniques for the determination of algal pigment fluorescence in environmental waters—Principles and guidelines for instrument and sensor selection, operation, quality assurance, and data reporting
The use of algal fluorometers by the U.S. Geological Survey (USGS) has become increasingly common. The basic principles of algal fluorescence, instrument calibration, interferences, data quantification, data interpretation, and quality control are given in Hambrook Berkman and Canova (2007). Much of the guidance given for instrument maintenance, data storage, and quality assurance in Wagner and ot
Combining eddy covariance and chamber methods to better constrain CO2 and CH4 fluxes across a heterogeneous restored tidal wetland
Carbon flux, storage, and wildlife co-benefits in a restoring estuary
Optical properties of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water at three watershed scales
Changing nitrogen inputs to the northern San Francisco Estuary: Potential ecosystem responses and opportunities for investigation
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.
Bay-Delta Water Quality Survey, 2018 and 2020 Comparison
Delta Survey Data Visualization Contents for 2018 and 2020
Bay- Delta Water Quality, Nutrient and Phytoplankton Mapping | US Geological Survey
Data visualization tool created for California's Bay-Delta Regional Monitoring Program. This web applicaton visualizes nutrients and phytoplankton spatially and temporally.
Assessing Phytoplankton and Nutrient Abundance in the San Francisco Estuary and Delta
A data visualizatoin exploring the relationship between nutrient distribution and phytoplankton under different conditions across the San Francisco Delta and Estuary. Assessing distribution and abundance aids understanding of how managing nutrient supplies affects aquatic food webs, helping managers evaluate the potential environmental benefits of future nutrient reduction efforts agains
Science and Products
- Science
Filter Total Items: 22
Remote Sensing of Mercury Pollution in South San Francisco Bay
San Francisco Bay has a long history of being subject to natural resources exploitation and pollution. Ongoing flux of contaminants into the bay, legacy pollution from the Gold Rush era and structural modifications still influence the natural ecosystem today. This project aims to map multiple forms (i.e. species) of mercury -- one of the major contaminants in the bay -- to help inform restoration...Biogeochemistry Group
The Biogeochemistry (BGC) Group uses an interdisciplinary approach to address surface water quality issues and food web dynamics throughout California, particularly in the Sacramento-San Joaquin Delta and San Francisco Bay.Sampling Locations for the Water Quality of San Francisco Bay Project
Since 1969, the Water Quality of San Francisco Bay Research and Monitoring Project has conducted water-column sampling along the deep channel of the San Francisco Bay-Delta system. Learn more about when and where we collect data.Sampling Methods for the Water Quality of San Francisco Bay Project
The Water Quality of San Francisco Bay Research and Monitoring Project measures changes in water quality along the deep channel of the San Francisco Bay-Delta system using submersible sensors and discrete water samples. Learn more about how we collect and measure water-quality data.Research Vessel David H. Peterson
The Research Vessel David H. Peterson begain service with the U.S. Geological Survey in 2015. Named after a founder of the Water Quality of San Francisco Bay Research and Monitoring Project, this vessel is a high-tech scientific platform for estuarine research. Learn more about how the R/V David H. Peterson makes our research possible.Assessing Sediment Nutrient Storage and Release in California's Sacramento-San Joaquin Delta
Sediments represent an important pool of nutrients in the Sacramento-San Joaquin Delta (Delta). The exchange of nutrients between the water column and the benthos impacts water quality and effects phytoplankton, harmful algal blooms, aquatic vegetation, and drinking water quality. To date, there is very limited information about nutrient pools in Delta sediments, nor how these nutrients are...Evaluating the effects of wastewater-derived nutrients on phytoplankton abundance and community structure in the San Francisco Estuary and Delta
Planned upgrades to the Sacramento Regional wastewater treatment plant (SRWTP) will substantially reduce nutrient discharge and also alter the types and amounts of nutrients being distributed across the San Francisco Delta and Estuary (Delta). One highly anticipated outcome of lower nutrients is improved productivity in the phytoplankton communities that supply aquatic food webs, which should...Water Quality of San Francisco Bay Research and Monitoring Project
Since 1969, the U.S. Geological Survey has maintained a research project in the San Francisco Bay-Delta system to measure and understand how estuarine systems and tidal river deltas function and change in response to hydro-climatic variability and human activities.Modeling Nitrogen Reduction Benefit to Invasive Aquatic Vegetation vs. Native Phytoplankton
Phytoplankton comprise the bottom of the aquatic food web and the abundance of phytoplankton serves as an indicator of healthy aquatic habitats. In the Sacramento-San Joaquin River Delta (Delta), competing with phytoplankton for required nitrogen, invasive aquatic vegetation (IAV) has increased exponentially in recent years. Once established, IAV can negatively impact local ecosystems and...Creating a Model to Predict Future Carbon Levels in Tidally-driven Marshes
Tidal marshes are important ecosystems in the San Francisco-Bay Delta. They remove carbon from the atmosphere, they build up soils that buffer our communities from sea level rise, they provide critical habitat and food resources for a diversity of species, and they reduce excessive nutrients which have a negative impact on water quality. As a result of land-use change and urbanization, the San...NASA-USGS National Blue Carbon Monitoring System
The NASA-USGS National Blue Carbon Monitoring System project will evaluate the relative uncertainty of iterative modeling approaches to estimate coastal wetland (marsh and mangrove) C stocks and fluxes based on changes in wetland distributions, using nationally available datasets (Landsat) and as well as finer scale satellite and field derived data in six sentinel sites.Trends in Dissolved Organic Carbon (DOC) in the Sacramento-San Joaquin Delta
Water from the Sacramento-San Joaquin Delta contains high concentrations of disinfection byproduct-forming (DBP-forming) materials when treated for potable use. DBPs form when dissolved organic compounds (DOC) in water react with disinfectants such as chlorine and ozone during the water treatment process. The amount of DBPs that form is a function of both the amount and source of the DOC, both of... - Data
Filter Total Items: 21
Above-water hyperspectral field spectroscopy measurements at Franks Tract in the Sacramento-San Joaquin Delta, California
Hand-held hyperspectral spectroscopy data were collected in 2022 in Franks Tract, a flooded area located in the central Sacramento-San Joaquin Delta of California. The data were collected from a boat and co-located within pixels from the Ocean Land Color Imaging (OLCI) sensor on the Sentinel-3A and 3-B satellites. Data from 16 sites within 7 OLCI pixels were collected on three days: July 14, AugusAssessing spatial variability of nutrients, phytoplankton, and related water-quality constituents in the San Francisco Bay, California: 2021-2022 High-resolution mapping surveys
The dataset documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the San Francisco Bay of California, USA in 2021 and 2022. The dataset includes nitrate, temperature, conductivity, dissolved oxygen, and chlorophyll as well as information about phytoplankton community composition. Data-collection cruises were conducted underWater quality, nutrient, and phytoplankton data from Franks Tract, Mildred Island, and neighboring channels in the California Sacramento-San Joaquin Delta: 2022 and 2023 High-resolution mapping surveys
Surface water quality, water isotope, and phytoplankton enumeration data were collected to evaluate the impact of an Emergency Drought Barrier (EDB) in False River in the Sacramento-San Joaquin Delta. Data were collected on six days during 2022 and 2023 (June 7, June 21, July 27, August 9, October 12, November 30, 2022, and February 21, 2023). Sampling occurred in Franks Tract, Mildred Island, theKdPAR and surface water-quality data collected in the Sacramento-San Joaquin River Delta in 2013 and 2014
Data release provides diffuse light attenuation coefficient of photosynthetically active radiation (KdPAR) derived from in-situ light measurements, along with surface water-quality and atmospheric data collected in the Sacramento-San Joaquin Rive Delta in California between January 2013 and May 2014. These associated surface level water-quality and atmospheric data, and categorical variables (forAssessing spatial variability of nutrients, phytoplankton and related water-quality constituents in the California Sacramento-San Joaquin Delta at the landscape scale: 2020-2021 High-resolution mapping surveys
The dataset documents the spatial and temporal variability of nutrients, phytoplankton, and related water quality parameters at high spatial resolution in the Sacramento-San Joaquin River Delta and Suisun Bay of California, USA. The dataset includes nitrate, ammonium, orthophosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, and chlorophyll as well as information aboutAssessing spatial variability of nutrients, phytoplankton, and related water quality constituents in the California Sacramento-San Joaquin Delta during treated wastewater effluent holds: August and September 2019 high resolution mapping surveys
The study is comprised of daily survey data consisting of high resolution mapping and discrete sample collection of nutrients, phytoplankton, and related water quality constituents conducted in the Sacramento River, Georgiana Slough, and the North and South Forks of the Mokelumne River on August 28 and September 10-12, 2019, coincident with planned holds of treated wastewater effluent from SacramePhytoplankton Species Composition and Abundance in the Sacramento-San Joaquin River Delta: Microscopic Enumeration of USGS Samples, beginning in 2016 (ver. 1.1, December 2023)
This dataset contains taxonomy, density (cells/mL), and biovolume (μm3/mL) data for phytoplankton sampled across the Sacramento San Joaquin River Delta and San Francisco Bay (Bay-Delta) beginning in 2016. Whole water phytoplankton samples were collected intermittently during special projects and during routine visits to service continuous monitoring stations. Samples were preserved with Lugol’s iAssessing spatial variability of nutrients, phytoplankton, and related water quality constituents in the California Sacramento-San Joaquin Delta related to the 2015 installation of the False River Emergency Drought Barrier: 2015 and 2016 high-resolution m
This data release documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the western and central portion of the Sacramento-San Joaquin River Delta of California, USA. The data set includes water residence time, nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and cHigh resolution and discrete temporal and spatial water-quality measurements in support of modeling mercury and methylmercury concentrations in surface waters of the Sacramento-San Joaquin River Delta
The Sacramento / San Joaquin River Delta (SSJRD) is contaminated with legacy mercury (Hg) from historical mining and mineral processing activities throughout the watershed, as well as from contemporary atmospheric and industrial inputs. The current project was designed for the purpose of developing high-resolution spatial and temporal models for estimating concentrations of mercury species in surfConcentration Data for 12 Elements of Concern Used in the Development of Surrogate Models for Estimating Elemental Concentrations in Surface Water of Three Hydrologic Basins (Delaware River, Illinois River and Upper Colorado River)
The release of metals (or metalloids) to surface water can involve both natural and anthropogenic sources. Elevated metals concentrations can pose a risk to human health, wildlife, and ecosystem health, with the modes of toxicity and extent of risk varying as a function of the specific metal, its chemical form and the matrix with which it is associated (for example, dissolved versus particulate).Tidal hydrologic and constitutent loads from First Mallard Water Quality Station in the Rush Ranch Marsh Complex of the San Francisco Bay Estuarine Research Reserve (SFBNERR) 2016-2018
The data herein report continuous field measurements and specific discrete sampling events associated with water quality and carbon consitutents - both dissolved and particulate forms. These data were coupled with atmospheric flux measurements during the 2017-18 water year to estimate the net storage of fixed carbon within the marsh on an areal basis. Direct and indirect measurement showed 47 to 5Characterization of water residence time, nutrients, phytoplankton and related water quality constituents in the Cache Slough Complex of the California Sacramento-San Joaquin Delta in 2017 and 2018
Data was collected in the Cache Slough Complex located in the northern San Francisco Estuary to characterize water quality parameters at high spatial resolution. Data collection was conducted on three separate occasions: October 2017, May 2018, and October 2018. Data set includes nitrate, ammonium, ortho-phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, c - Publications
Filter Total Items: 106
Assessing spatial variability of nutrients, phytoplankton, and related water-quality constituents in the California Sacramento–San Joaquin Delta at the landscape scale—2018 high resolution mapping surveys
Executive Summary This study examined the abundance and distribution of nutrients and phytoplankton in the tidal aquatic environments of the Sacramento–San Joaquin Delta (Delta) and Suisun Bay, comprising three spatial surveys conducted in May, July, and October of 2018 that used continuous underway high frequency sampling and measurements onboard a high-speed boat to characterize spatial variatioAuthorsBrian A. Bergamaschi, Tamara E. C. Kraus, Bryan D. Downing, Elizabeth B. Stumpner, Katy O'Donnell, Jeffrey A. Hansen, Jeniffer Soto Perez, Emily T. Richardson, Angela M. Hansen, Alan GelberEvaluation and refinement of chlorophyll-a algorithms for high-biomass blooms in San Francisco Bay (USA)
A massive bloom of the raphidophyte Heterosigma akashiwo occurred in summer 2022 in San Francisco Bay, causing widespread ecological impacts including events of low dissolved oxygen and mass fish kills. The rapidly evolving bloom required equally rapid management response, leading to the use of near-real-time image analysis of chlorophyll from the Ocean and Land Colour Instrument (OLCI) aboard SenAuthorsRaphael M. Kudela, David B. Senn, Emily T. Richardson, Keith Bouma-Gregson, Brian A. Bergamaschi, Lawrence SimPhysics to fish—Understanding the factors that create and sustain native fish habitat in the San Francisco Estuary
Executive SummaryThe Bureau of Reclamation (Reclamation) operates the Central Valley Project (CVP), one of the nation’s largest water projects. Reclamation has an ongoing need to improve the scientific basis for adaptive management of the CVP and, by extension, joint operations with California’s State Water Project. The U.S. Geological Survey (USGS) works cooperatively with the Bureau of ReclamatiAuthorsLarry R. Brown, David E. Ayers, Brian A. Bergamaschi, Jon R. Burau, Evan T. Dailey, Bryan D. Downing, Maureen A. Downing-Kunz, Frederick V. Feyrer, Brock M. Huntsman, Tamara E. C. Kraus, Tara Morgan, Jessica R. Lacy, Francis Parchaso, Catherine A. Ruhl, Elizabeth B. Stumpner, Paul Stumpner, Janet Thompson, Matthew J. YoungA simple approach to modeling light attenuation in the Sacramento-San Joaquin Delta using commonly available data
The diffuse attenuation coefficient of photosynthetically active radiation (KdPAR) is commonly used to predict light attenuation in aquatic productivity models, but obtaining measurements of PAR to compute KdPAR is difficult. In situ calculations of KdPAR require multiple measurements of PAR through the water column, and these measurements are infeasible for real-time recording. Instead, predictivAuthorsEmily T. Richardson, Keith Bouma-Gregson, Katy O'Donnell, Brian A. BergamaschiA novel boat-based field application of a high-frequency conductometric ammonium analyzer to characterize spatial variation in aquatic ecosystems
Documenting dissolved inorganic nitrogen (DIN) concentration and form at appropriate temporal and spatial scales is key to understanding aquatic ecosystem health, particularly as DIN fuels primary productivity. In addition to point and non-point source nutrient inputs, factors such as hydrology, geomorphology, temperature, light, and biogeochemical transformations influence nutrient dynamics in suAuthorsEmily T. Richardson, Angela Hansen, Tamara E. C. Kraus, Bryan D. Downing, Don Forsberg, John Stillian, Katy O'Donnell, Crystal Lee Sturgeon, Brian A. BergamaschiField techniques for fluorescence measurements targeting dissolved organic matter, hydrocarbons, and wastewater in environmental waters: Principles and guidelines for instrument selection, operation and maintenance, quality assurance, and data reporting
The use of field deployable fluorescence sensors by the U.S. Geological Survey has become increasingly common for a wide variety of surface water and groundwater investigations. This report addresses field deployable fluorometers that measure the fluorescence response of various substances in water exposed to incident light generated by the sensor. An introduction to the basic principles of fieldAuthorsAmanda Booth, Jacob Fleck, Brian A. Pellerin, Angela Hansen, Alexandra Etheridge, Guy M. Foster, Jennifer L. Graham, Brian A. Bergamaschi, Kurt D. Carpenter, Bryan D. Downing, Stewart A. Rounds, JohnFranco SaracenoIncreased salinity decreases annual gross primary productivity at a Northern California brackish tidal marsh
Tidal marshes sequester 11.4–87.0 Tg C yr−1 globally, but climate change impacts can threaten the carbon capture potential of these ecosystems. Tidal marshes occur across a wide range of salinity, with brackish marshes (0.5–18 ppt (parts per thousand)) dominating global tidal marsh extents. A diverse mix of freshwater- and saltwater-tolerant plant and microbial communities has led researchers to pAuthorsSarah Russell, Lisamarie Windham-Myers, Ellen J Goodrich-Stuart, Brian A. Bergamaschi, Frank Anderson, Patty Oikawa, Sara KnoxField techniques for the determination of algal pigment fluorescence in environmental waters—Principles and guidelines for instrument and sensor selection, operation, quality assurance, and data reporting
The use of algal fluorometers by the U.S. Geological Survey (USGS) has become increasingly common. The basic principles of algal fluorescence, instrument calibration, interferences, data quantification, data interpretation, and quality control are given in Hambrook Berkman and Canova (2007). Much of the guidance given for instrument maintenance, data storage, and quality assurance in Wagner and ot
AuthorsGuy M. Foster, Jennifer L. Graham, Brian A. Bergamaschi, Kurt D. Carpenter, Bryan D. Downing, Brian A. Pellerin, Stewart A. Rounds, John Franco SaracenoCombining eddy covariance and chamber methods to better constrain CO2 and CH4 fluxes across a heterogeneous restored tidal wetland
Tidal wetlands play an important role in global carbon cycling by storing carbon in sediment at millennial time scales, transporting dissolved carbon into coastal waters, and contributing significantly to global CH4 budgets. However, these ecosystems' greenhouse gas monitoring and predictions are challenging due to spatial heterogeneity and tidal flooding. We utilized eddy covariance and chamber mAuthorsJulie Shahan, Housen Chu, Lisamarie Windham-Myers, Maiyah Matsumura, Joseph Carlin, Elke Eichelmann, Ellen J Goodrich-Stuart, Brian A. Bergamaschi, Kyle Kensuke Nakatsuka, Cove Sturtevant, Patty OikawaCarbon flux, storage, and wildlife co-benefits in a restoring estuary
Tidal marsh restorations may result in transitional mudflat habitats depending on hydrological and geomorphological conditions. Compared to tidal marsh, mudflats are thought to have limited value for carbon sequestration, carbon storage, and foraging benefits for salmon. We evaluated greenhouse gas exchange, sediment carbon storage, and invertebrate production at restoration and reference tidal maAuthorsIsa Woo, Melanie J. Davis, Susan E. W. De La Cruz, Lisamarie Windham-Myers, Judith Z. Drexler, Kristin B. Byrd, Ellen Stuart-Haëntjens, Frank E Anderson, Brian A. Bergamaschi, Glynnis Nakai, Christopher S. Ellings, Sayre HodgsonOptical properties of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water at three watershed scales
Relations between spectral absorbance and fluorescence properties of water and human-associated and fecal indicator bacteria were developed for facilitating field sensor applications to estimate wastewater contamination in waterways. Leaking wastewater conveyance infrastructure commonly contaminates receiving waters. Methods to quantify such contamination can be time consuming, expensive, and ofteAuthorsSteven R. Corsi, Laura A. DeCicco, Angela Hansen, Peter L. Lenaker, Brian A. Bergamaschi, Brian A. Pellerin, Debra Dila, Melinda Bootsma, Susan Spencer, Mark A. Borchardt, Sandra L. McLellanChanging nitrogen inputs to the northern San Francisco Estuary: Potential ecosystem responses and opportunities for investigation
Anthropogenic activities have resulted in elevated ambient nitrogen (N) and phosphorus (P) concentrations in many regions of the Sacramento-San Joaquin Delta and Suisun Bay (northern San Francisco Estuary, (nSFE). The Sacramento Regional wastewater treatment plant (SRWTP WWTP) currently acts as the largest N point source to the system, discharging 13,000-15,000 kg/d of ammonium-N (NH4) near the nSAuthorsDavid Senn, Tamara E. C. Kraus, Amy Richey, Brian A. Bergamaschi, Larry R. Brown, Louise Conrad, Christopher A. Francis, Wim Kimmerer, Raphael Kudela, Timothy G. Otten, Alexander E. Parker, April Robinson, Anke Mueller-Solger, Dylan Stern, Janet ThompsonNon-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
Bay-Delta Water Quality Survey, 2018 and 2020 Comparison
Delta Survey Data Visualization Contents for 2018 and 2020
Bay- Delta Water Quality, Nutrient and Phytoplankton Mapping | US Geological Survey
Data visualization tool created for California's Bay-Delta Regional Monitoring Program. This web applicaton visualizes nutrients and phytoplankton spatially and temporally.
Assessing Phytoplankton and Nutrient Abundance in the San Francisco Estuary and Delta
A data visualizatoin exploring the relationship between nutrient distribution and phytoplankton under different conditions across the San Francisco Delta and Estuary. Assessing distribution and abundance aids understanding of how managing nutrient supplies affects aquatic food webs, helping managers evaluate the potential environmental benefits of future nutrient reduction efforts agains
- News