Generalized diagram of an alum application system (from
Kennedy and Cooke 198'2)
limit the treatment area, but produces nearly the effectiveness of a treatment
of the entire reservoir (Cooke and
It should be recognized that there may be extensive phosphorus release
from aerobic sediments and sediments exposed to high
such as may occur in
Much of the
littoral areas during periods of high rates of photosynthesis.
release of nutrients involves microbial metabolism and can be expected to be
Also, it should be noted that a range of sedi-
high when the water is warm.
ment types having various phosphorus sorptive or phosphorus release character-
An exceptional review of this topic is
istics may be found in a reservoir.
provided by Bostrom, Jansson, and Forsberg (1982).
The areas of highest potential phosphorus release can be determined by
studying release rates of sediment cores in the laboratory.
ments are obtained with an Ekman dredge, or a corer, from shallow and deep