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Katy O'Donnell

Katy O'Donnell - California Water Science Center

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Scientists aboard research vessel conduct water-quality mapping in support of wastewater-derived nutrients project

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.
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California Water Science Center
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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.
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Microscopic view of a phytoplankton cell collected in San Francisco Bay

Causes and Relevance of Phytoplankton Blooms in the Northern Sacramento-San Joaquin Delta

Phytoplankton are an important part of aquatic food webs and ecosystems. These single-celled plants grow faster in the stronger light of spring or summer, resulting in population explosions called phytoplankton blooms. These blooms in turn feed zooplankton (free-floating aquatic microorganisms), providing food for many aquatic species, including fish, shrimp, crabs, and other invertebrates.
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California Water Science Center
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Causes and Relevance of Phytoplankton Blooms in the Northern Sacramento-San Joaquin Delta

Phytoplankton are an important part of aquatic food webs and ecosystems. These single-celled plants grow faster in the stronger light of spring or summer, resulting in population explosions called phytoplankton blooms. These blooms in turn feed zooplankton (free-floating aquatic microorganisms), providing food for many aquatic species, including fish, shrimp, crabs, and other invertebrates.
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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

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 c
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California Water Science Center

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

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 surf
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Water Resources Mission Area

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

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
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California Water Science Center

Spatial assessment of nutrients and water-quality constituents in Suisun Marsh with the salinity control gate reoperation experiment; a Delta Smelt Resiliency Strategy experiment 2018

This data release documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in Suisun Marsh and Suisun Bay in the San Francisco Estuary of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, chlorophyll, blue-green algal pigments, and
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California Water Science Center

Assessment of water-quality in the California Sacramento-San Joaquin Delta during a North Delta directed flow action: August - October 2018

This report documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll . Data-collection cruises were co
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California Water Science Center

Assessment of nutrients and water-quality constituents in the North Delta during Yolo Bypass flooding events in March 2017

The data release contains data for the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll. Data-collection cru
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California Water Science Center

Assessment of nutrients and water-quality constituents at the Sacramento-San Joaquin River Confluence during a phytoplankton bloom in July 2017

This report documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll. Data-collection were conducted o
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California Water Science Center

High-Resolution Measurements to Identify Effects of Aquatic Vegetation on Water Quality and Stratification

The dataset documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta of the Sacramento-San Joaquin River Delta of California, USA. The dataset includes surface mapping, depth profile, and discrete data for nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, and chl
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California Water Science Center

High-speed, continuous water quality mapping of Utah Lake, Salt Lake City, UT

Real-time, high frequency (1-second sample interval), georeferenced water quality data was collected in Utah Lake, Utah. Utah Lake is located approximately 45 miles south of Salt Lake City, Utah, and approximately 5 miles west of Provo, Utah. Data was collected on 8/1/16 over an approximate 6.5-hour period (8:00 14:30 h PST) while underway. Sample water was continuously pumped through a pickup tu
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California Water Science Center

Continuous underway water quality and water isotope measurements in a hydrodynamically complex tidal environment

Real-time, high frequency (1-second sample interval) GPS location, water quality, and water isotope (δ2H, δ18O) data was collected in the Cache Slough Complex (CSC), located in the northern San Francisco Bay Delta (SFBD). Data was collected on 10/01/2014 for an approximate 4-hour period (10:30 14:30 h PST) while underway on the R/V Mary Landsteiner, a 26-foot USGS vessel. Sample water was pumped
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California Water Science Center

Using structured decision making to evaluate potential management responses to detection of dreissenid mussel (Dreissena spp.) environmental DNA

Environmental (e)DNA tools are sensitive and cost-effective for early detection of invasive species. However, the uncertainty associated with the interpretation of positive eDNA detections makes it challenging to determine appropriate natural resource management responses. Multiple sources of error can give rise to positive detections of eDNA in a sample when individuals of that species are not pr
Authors
Adam J. Sepulveda, David R. Smith, Katherine M O'Donnell, Nathan Owens, Brittany White, Catherine A. Richter, Christopher M. Merkes, Skylar Wolf, Mike Rau, Matthew Neilson, Wesley Daniel, Christine E. Dumoulin, Margaret Hunter
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Ecosystems Mission Area, Columbia Environmental Research Center, Northern Rocky Mountain Science Center, Upper Midwest Environmental Sciences Center, Wetland and Aquatic Research Center

Using paired in situ high frequency nitrate measurements to better understand controls on nitrate concentrations and estimate nitrification rates in a wastewater-impacted river

We used paired continuous nitrate ( ) measurements along a tidally affected river receiving wastewater discharge rich in ammonium ( ) to quantify rates of change in  concentration ( ) and estimate nitrification rates.  sensors were deployed 30 km apart in the Sacramento River, California (USA), with the upstream station located immediately above the regional wastewater treatment plant (WWTP). We u
Authors
Tamara E. C. Kraus, Katy O'Donnell, Bryan D. Downing, Jon R. Burau, Brian A. Bergamaschi
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Water Resources Mission Area, California Water Science Center

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.

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California Water Science Center

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