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Introduction How Rivers Run Stories Value Of A River What We Can Do
Quality of a River - Water Quality
Dissolved oxygen (pg 2 of 4)

Riffles and other turbulence help to saturate water with dissolved oxygen. Photosynthesis from aquatic plants also oxygenates water.

Other processes remove oxygen from the water. Rising temperature is one. Respiration of fish, insects, zooplankton, algae, and other plants and animals is another. Chemical reactions is a third process.

Decomposition also removes oxygen from water. A stream carrying a large quantity of nonliving organic matter, such as a decaying algae bloom or a load of only partially treated sewage, is said to have a high biochemical oxygen demand. Biochemical oxygen demand (BOD) represents the amount of dissolved oxygen consumed by bacteria and other microorganisms as they decompose the organic matter in the water.


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Introduction
Flow
Shape
Connections
Quality
Description
Temperature
Oxygen
Alkalinity
Nutrients
Sediment
Contaminants
Status
Life
Summary
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