Photograph of Brett D. Johnston taken in Winter Garden, Florida, facing forward with a neutral expression.
Brett D Johnston
Hydrologist at the Caribbean-Florida Water Science Center, specializing in scientific investigations that apply advanced sensing technologies and methods to support water-quality research.
Brett D. Johnston began his career with the USGS in 2007. He has a B.S. degree in Environmental Science from the University of Central Florida. For over a decade, his studies have been focused on evaluating and using next-generation observing systems, such as those utilizing hydroacoustic or optical (attenuation, absorbance, and fluorescence) technologies, to advance the understanding of spatiotemporal dynamics in nutrients and phytoplankton communities. Presently, Brett's research centers on utilizing continuous water-quality and environmental sensors to enhance predictive capabilities for harmful algal bloom events.
Science and Products
Field Data for an Evaluation of Sensors for Continuous Monitoring of Harmful Algal Blooms in the Finger Lakes Region, New York, 2018 - 2020 Field Data for an Evaluation of Sensors for Continuous Monitoring of Harmful Algal Blooms in the Finger Lakes Region, New York, 2018 - 2020
This U.S. Geological Survey (USGS) data release contains meteorological, water temperature, light (photosynthetically active radiation and illumination), and multichannel fluorescence sensor data from the Finger Lakes Region of New York, during the fall of 2018 and the summer and fall of 2019 and 2020. It also includes all sensor data and associated discrete sample data, at the near...
Meteorological Data from Great South Bay at Watch Hill on Fire Island, New York, 2017 to 2022 Meteorological Data from Great South Bay at Watch Hill on Fire Island, New York, 2017 to 2022
This data release contains meteorological sensor data (6-minute intervals) collected at Great South Bay at Watch Hill on Fire Island (USGS station number, 01305575), New York, from 2017 to 2022. Measured parameters include: air pressure, air temperature, precipitation, relative humidity, solar radiation, wind direction and speed, and wind-gust direction and speed. Data users are...
Laboratory and Field Data for a Performance Evaluation of the PhytoFind, an In-Place Phytoplankton Classification Tool Laboratory and Field Data for a Performance Evaluation of the PhytoFind, an In-Place Phytoplankton Classification Tool
This data release presents the laboratory and field results of a performance evaluation conducted on the Turner Designs, Inc., PhytoFind, an in-place phytoplankton classification tool. The laboratory evaluation included tests that were designed to characterize PhytoFind performance under a range of conditions that may affect phytoplankton fluorescence and sensor response. Laboratory...
Microcystin, chlorophyll, and cell-count data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 9 to 17, 2017 Microcystin, chlorophyll, and cell-count data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 9 to 17, 2017
This U.S. Geological Survey (USGS) Data Release provides microcystin, chlorophyll, and cell-count data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida. All data are reported as raw measured values and are not rounded to USGS significant figures. Water and algal bloom material were collected from Lake...
Velocity test data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 10 to 13, 2017 Velocity test data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 10 to 13, 2017
This U.S. Geological Survey (USGS) Data Release provides velocity test data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 10 to 13, 2017. All data are reported as raw measured values and are not rounded to USGS significant figures. Water and algal bloom material were collected from Lake Okeechobee...
Picture of Brett D. Johnston
Photograph of Brett D. Johnston taken in Winter Garden, Florida, facing forward with a neutral expression.
Spatiotemporal variability of algal biomass and nitrate in Owasco and Seneca Lakes in the Finger Lakes Region, New York, in 2019 Spatiotemporal variability of algal biomass and nitrate in Owasco and Seneca Lakes in the Finger Lakes Region, New York, in 2019
Cyanobacterial harmful algal blooms (CyanoHABs) have become increasingly common, threatening the security of water resources globally. The U.S. Geological Survey conducted high-resolution nearshore mapping surveys using boat-mounted multiparameter sondes and nitrate sensors during the summer and fall of 2019 on Owasco Lake and Seneca Lake, two lakes with documented CyanoHABs in the...
Authors
Michael Stouder, Sabina Gifford, Kristina Gutchess, Kaitlyn Finkelstein, Brett Johnston, Karen Beaulieu, Joshua Rosen, Megan Essig, Guy Foster
Evaluation of passive samplers for cyanotoxin detection by immunoassay and chromatographic-mass spectrometry Evaluation of passive samplers for cyanotoxin detection by immunoassay and chromatographic-mass spectrometry
Harmful algal blooms, particularly cyanobacterial harmful algal blooms, threaten aquatic ecosystems, drinking water supplies, and recreational resources. In 2019, the U.S. Geological Survey, in collaboration with the New York State Department of Environmental Conservation, deployed solid phase adsorption toxin tracking (SPATT) samplers in Seneca Lake, Owasco Lake, and Skaneateles Lake to...
Authors
Brett Johnston, Michael Stouder, Rebecca Gorney, Joshua Rosen, Kurt Carpenter, Bofan Wei, Gregory Boyer
Evaluation of sensors for continuous monitoring of harmful algal blooms in the Finger Lakes region, New York, 2019 and 2020 Evaluation of sensors for continuous monitoring of harmful algal blooms in the Finger Lakes region, New York, 2019 and 2020
In response to the increasing frequency of cyanobacterial harmful algal blooms (CyanoHABs) in the Finger Lakes region of New York State, a pilot study by the U.S. Geological Survey, in collaboration with the New York State Department of Environmental Conservation, was conducted to enhance CyanoHAB monitoring and understanding. High-frequency sensors were deployed on open water monitoring...
Authors
Brett Johnston, Kaitlyn Finkelstein, Sabina Gifford, Michael Stouder, Elizabeth Nystrom, Philip Savoy, Joshua Rosen, Matthew Jennings
Technical note—Performance evaluation of the PhytoFind, an in-place phytoplankton classification tool Technical note—Performance evaluation of the PhytoFind, an in-place phytoplankton classification tool
In 2019, the U.S. Geological Survey evaluated the performance of the Turner Designs, Inc. PhytoFind, an in-place phytoplankton classification tool. The sensor was tested with sample blanks, monoculture and mixed phytoplankton cultures, and turbidity challenges in a laboratory, and was tested on a 120-mile survey of the Caloosahatchee and St. Lucie Rivers in Florida, including Lake...
Authors
Brett Johnston, Jennifer Graham, Guy Foster, Bryan Downing
Understanding the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida Understanding the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida
In an effort to simulate the survival of cyanobacteria asthey are transported from Lake Okeechobee to the estuarinehabitats that receive waters from the lake, a bioassayencompassing a range of salinities was performed. An overalldecline in cyanobacteria health in salinity treatments greaterthan 18 practical salinity units (psu) was indicated by loss ofcell membrane integrity based on...
Authors
Barry Rosen, Keith A. Loftin, Jennifer L. Graham, Katherine Stahlhut, James Riley, Brett Johnston, Sarena Senegal
Water quality in the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee, 1999-2001 Water quality in the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee, 1999-2001
This report contains the major findings of a 1999?2001 assessment of water quality in the Mobile River Basin. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues...
Authors
J. Atkins, Humbert Zappia, James Robinson, Ann McPherson, Richard Moreland, Douglas Harned, Brett Johnston, John Harvill
Science and Products
Field Data for an Evaluation of Sensors for Continuous Monitoring of Harmful Algal Blooms in the Finger Lakes Region, New York, 2018 - 2020 Field Data for an Evaluation of Sensors for Continuous Monitoring of Harmful Algal Blooms in the Finger Lakes Region, New York, 2018 - 2020
This U.S. Geological Survey (USGS) data release contains meteorological, water temperature, light (photosynthetically active radiation and illumination), and multichannel fluorescence sensor data from the Finger Lakes Region of New York, during the fall of 2018 and the summer and fall of 2019 and 2020. It also includes all sensor data and associated discrete sample data, at the near...
Meteorological Data from Great South Bay at Watch Hill on Fire Island, New York, 2017 to 2022 Meteorological Data from Great South Bay at Watch Hill on Fire Island, New York, 2017 to 2022
This data release contains meteorological sensor data (6-minute intervals) collected at Great South Bay at Watch Hill on Fire Island (USGS station number, 01305575), New York, from 2017 to 2022. Measured parameters include: air pressure, air temperature, precipitation, relative humidity, solar radiation, wind direction and speed, and wind-gust direction and speed. Data users are...
Laboratory and Field Data for a Performance Evaluation of the PhytoFind, an In-Place Phytoplankton Classification Tool Laboratory and Field Data for a Performance Evaluation of the PhytoFind, an In-Place Phytoplankton Classification Tool
This data release presents the laboratory and field results of a performance evaluation conducted on the Turner Designs, Inc., PhytoFind, an in-place phytoplankton classification tool. The laboratory evaluation included tests that were designed to characterize PhytoFind performance under a range of conditions that may affect phytoplankton fluorescence and sensor response. Laboratory...
Microcystin, chlorophyll, and cell-count data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 9 to 17, 2017 Microcystin, chlorophyll, and cell-count data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 9 to 17, 2017
This U.S. Geological Survey (USGS) Data Release provides microcystin, chlorophyll, and cell-count data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida. All data are reported as raw measured values and are not rounded to USGS significant figures. Water and algal bloom material were collected from Lake...
Velocity test data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 10 to 13, 2017 Velocity test data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 10 to 13, 2017
This U.S. Geological Survey (USGS) Data Release provides velocity test data for assessing the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida, July 10 to 13, 2017. All data are reported as raw measured values and are not rounded to USGS significant figures. Water and algal bloom material were collected from Lake Okeechobee...
Picture of Brett D. Johnston
Photograph of Brett D. Johnston taken in Winter Garden, Florida, facing forward with a neutral expression.
Photograph of Brett D. Johnston taken in Winter Garden, Florida, facing forward with a neutral expression.
Spatiotemporal variability of algal biomass and nitrate in Owasco and Seneca Lakes in the Finger Lakes Region, New York, in 2019 Spatiotemporal variability of algal biomass and nitrate in Owasco and Seneca Lakes in the Finger Lakes Region, New York, in 2019
Cyanobacterial harmful algal blooms (CyanoHABs) have become increasingly common, threatening the security of water resources globally. The U.S. Geological Survey conducted high-resolution nearshore mapping surveys using boat-mounted multiparameter sondes and nitrate sensors during the summer and fall of 2019 on Owasco Lake and Seneca Lake, two lakes with documented CyanoHABs in the...
Authors
Michael Stouder, Sabina Gifford, Kristina Gutchess, Kaitlyn Finkelstein, Brett Johnston, Karen Beaulieu, Joshua Rosen, Megan Essig, Guy Foster
Evaluation of passive samplers for cyanotoxin detection by immunoassay and chromatographic-mass spectrometry Evaluation of passive samplers for cyanotoxin detection by immunoassay and chromatographic-mass spectrometry
Harmful algal blooms, particularly cyanobacterial harmful algal blooms, threaten aquatic ecosystems, drinking water supplies, and recreational resources. In 2019, the U.S. Geological Survey, in collaboration with the New York State Department of Environmental Conservation, deployed solid phase adsorption toxin tracking (SPATT) samplers in Seneca Lake, Owasco Lake, and Skaneateles Lake to...
Authors
Brett Johnston, Michael Stouder, Rebecca Gorney, Joshua Rosen, Kurt Carpenter, Bofan Wei, Gregory Boyer
Evaluation of sensors for continuous monitoring of harmful algal blooms in the Finger Lakes region, New York, 2019 and 2020 Evaluation of sensors for continuous monitoring of harmful algal blooms in the Finger Lakes region, New York, 2019 and 2020
In response to the increasing frequency of cyanobacterial harmful algal blooms (CyanoHABs) in the Finger Lakes region of New York State, a pilot study by the U.S. Geological Survey, in collaboration with the New York State Department of Environmental Conservation, was conducted to enhance CyanoHAB monitoring and understanding. High-frequency sensors were deployed on open water monitoring...
Authors
Brett Johnston, Kaitlyn Finkelstein, Sabina Gifford, Michael Stouder, Elizabeth Nystrom, Philip Savoy, Joshua Rosen, Matthew Jennings
Technical note—Performance evaluation of the PhytoFind, an in-place phytoplankton classification tool Technical note—Performance evaluation of the PhytoFind, an in-place phytoplankton classification tool
In 2019, the U.S. Geological Survey evaluated the performance of the Turner Designs, Inc. PhytoFind, an in-place phytoplankton classification tool. The sensor was tested with sample blanks, monoculture and mixed phytoplankton cultures, and turbidity challenges in a laboratory, and was tested on a 120-mile survey of the Caloosahatchee and St. Lucie Rivers in Florida, including Lake...
Authors
Brett Johnston, Jennifer Graham, Guy Foster, Bryan Downing
Understanding the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida Understanding the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida
In an effort to simulate the survival of cyanobacteria asthey are transported from Lake Okeechobee to the estuarinehabitats that receive waters from the lake, a bioassayencompassing a range of salinities was performed. An overalldecline in cyanobacteria health in salinity treatments greaterthan 18 practical salinity units (psu) was indicated by loss ofcell membrane integrity based on...
Authors
Barry Rosen, Keith A. Loftin, Jennifer L. Graham, Katherine Stahlhut, James Riley, Brett Johnston, Sarena Senegal
Water quality in the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee, 1999-2001 Water quality in the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee, 1999-2001
This report contains the major findings of a 1999?2001 assessment of water quality in the Mobile River Basin. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues...
Authors
J. Atkins, Humbert Zappia, James Robinson, Ann McPherson, Richard Moreland, Douglas Harned, Brett Johnston, John Harvill