IMHO, Oxygen is the key element to make all these things happen.
Low DOC (Dissolved Oxygen Content) and things start breaking down.

DOC stands for Dissolved Organic Carbon, the pollutants removed by
foam fractionation. See http://pearl.spatial.maine.edu/glossary/misc/doc.htm

I used to (until 10 seconds ago) think it stood for Dissolved
Organic Compounds until I googled to prevent foot-in-mouth...

A google for "doc dissolved oxygen" reveals that DO stands for Dissolved
Oxygen.

I still think that "Organic Carbon" is redundant

Pedantic nit of the day, brought to you by Andy.