Protecting Hamlin Lake for future Generations
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  Dissolved Oxygen and Temperature Profile
  In our lake, the role of bacteria is to decompose organic matter.  Dissolved oxygen is essential for all aquatic organism that breath.
  • Without oxygen beneficial bacteria, insects, and fish cannot thrive.
View Data From:
  • Without oxygen anaerobic bacteria release phosphorus and nitrogen into the lake which then fertilizes  green growth.
2012 Upper
  • Lack of oxygen results in disagreeable odors.
2012 Lower
  • Without oxygen at the bottom, organic sediment builds up.
  The atmosphere has about 20% oxygen, and when our lake water is in equilibrium with air it has about 8 to 9 mg/l, or ppm, of dissolved oxygen (DO).
  Oxygen concentration above 9 mg/l results when bright sunlight causes green algae to generate oxygen.
  Oxygen concentration below 8 mg/l results when micro-organisms consume (breath) oxygen.
  Dissolved Oxygen and Temperature profiles are obtained by lowering weighted instruments, attached to a calibrated cable, and in turn to instruments in a boat.
  Hamlin Lake Preservation Society, PO Box 178, Ludington, MI 49431