Monitoring the quality of rivers and lakes is becoming more and more important as enviornmental concerns increase. A good
dissolved oxygen transmitter used properly is one of the important tools to use in this regard. You may want to look at http://www.ecy.wa.gov/programs/wq/plants/management/joysmanual/4oxygen.html for some useful techniques.
Glossary for Water Quality Testing Terms
Below are the terms relating to Water Quality Testing for the section you have selected.
Geothermal
Geothermal Research