Carbon dioxide is an important gas in lakes. Although highly
soluble in water, most carbon dixide in lakes is formed as an
end product of respiration. As carbon dioxide dissolves in
water, it form a series of compounds, including carbonic acid,
bicarbonate and carbonate. The resulting carbonate chemistry,
along with common anions such as hydroxide (OH-) and sulfate
(SO4-), contribute to the alkalinity (buffering capacity) of
water. Alkalinity is a measure of the ability of water to resist
changes in PH, which is a measure of the amount of acidity. A
neutral pH is 7; acidic conditions have pH less than 7; and
alkaline solution have pH greater than 7. Many aquatic organisms
have fairly strict pH requirements, so the amount and stability
of pH is very important. For example, the poorly buffered lakes
they are unable to resist changes in pH caused by acidic
precipitation, and the resulting low pH values (<5.5) reduced
the diversity of organisms to only those few adapted to low pH.
Alkalinity is a conservative par