pH

• pH is the measurement of how many Hydrogen ions are in the water
• A high number of Hydrogen ions make the water acidic, a low number make the water alkaline
• Healthy lakes usually have a pH of around 6, pure water has a pH of 7
• pH is measured using specialized probes that count the number of Hydrogen ions in the water.

     Another important measurement to take when studying a lake is pH, to determine if the lake is acidic or alkaline.  The pH of the lake can vary throughout the year but it is important that it stays within a range that is healthy for the fish.  The amount of total dissolved solids or chlorophyll in the water will affect the pH.  A high concentration of phytoplankton can increase the pH due to the decrease of carbon dioxide in the water.  When bacteria break down the dead material on the bottom of the lake; the pH level decreases because carbon dioxide is released into the water.  The definition of pH refers to how many hydrogen ions are present in the water and that is exactly what the instrument measures.  Scientists are interested in monitoring the pH levels in a lake not only to ensure that the water is safe for the organisms living there but also to gain a better understanding of what is happening beneath the surface.