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USGS personnel collect a water-quality sample on the Missouri River. USGS/Photo by Kelly Brady.
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6.2 Dissolved Oxygen
Revised By Stewart A. Rounds, Franceska D. Wilde, and George F. Ritz
This section of Chapter 6 is available as a pdf file:
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[September, 2013 -- Version 3.0 incorporates the changes that were made to the method for computing dissolved-oxygen solubility, as described in Water Quality Technical Memorandum 2011.03 and implemented in version 3 of DOTABLES software http://water.usgs.gov/software/DOTABLES/].
Accurate data for the concentration of dissolved oxygen in surface and ground waters are essential for documenting changes in environmental water resources that result from natural phenomena and human activities. Dissolved oxygen is necessary in aquatic systems for the survival and growth of many aquatic organisms and is used as an indicator of the health of surface-water bodies. This section of the National Field Manual (NFM) includes U.S. Geological Survey (USGS) guidance and protocols for four methods to determine dissolved-oxygen concentrations: the amperometric, luminescence (optical), spectrophotometric, and iodometric (Winkler) methods.
6.2 Dissolved Oxygen
6.2.1 Optical (Luminescence) and Amperometric Sensor Methods
6.2.1.A Equipment and Field Preparations
Equipment Description and Maintenance
Field trip preparations
6.2.1.B Calibration of Optical and Amperometric Sensors
Correction for Atmospheric Pressure and Salinity
Selection of Calibration Method
Optical (Luminescence) DO Sensors: Calibration Procedures
Amperometric (Clark cell) DO Sensors: Calibration Procedures
6.2.1.D Troubleshooting for Amperometric Instruments
6.2.2 Spectrophotometric (Rhodazine-D and Indigo-Carmine) Methods
6.2.2.A Equipment and Supplies
6.2.2.B Calibration and Interferences
6.2.3 Iodometric (Winkler) Method
6.2.3.A Equipment and Supplies
6.2.5 Correction Factors for Oxygen Solubility Concentrations and Salinity
Section 6.2 Archived Versions: