Sediments are enriched with nutrients and organic matter by sedimentation of organic
materials to the pond bottom. The concentrations of nutrients (including organic carbon
compounds) in the pond bottom soil are typically several orders of magnitude higher
than those found in the water (Table 3). The amounts of nutrients in a 1-cm layer of the
pond bottom are normally about 10 or more times higher than the equivalent amounts in
a 1-m deep water column. The bottom becomes a favorable site for microbial development
due to the availability of organic matter. Bacteria consume large amounts of