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6.2 Dissolved Oxygen
Revised By Michael E. Lewis
This section of Chapter 6 is available as a pdf file:
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[August, 2011 -- This section is being revised to incorporate changes that have been 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, luminescent-sensor, spectrophotometric, and iodometric (Winkler) methods.
6.2 Dissolved Oxygen
6.2.1 Amperometric and luminescent-sensor methods
6.2.1.A Equipment and supplies
One-point and two-point calibrations
Correction for atmospheric pressure and salinity
1. Air-calibration chamber in air
2. Calibration with air-saturated water
3. Air-calibration chamber in water
6.2.1.D Troubleshooting (amperometric instruments)
6.2.2 Spectrophotometric method
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 and salinity
Section 6.2 Archived Versions: