Abstract
Studies were conducted near Manaus, Brazil in cooperation with INPA to try to establish how nutrient cycling influences the formation of black water and white water. The studies measured the rate of decay of Caryocar villosum leaves on spodosol and oxisol terrestrial and aquatic sites when the leaves were untreated, and treated with a bacteriostat, or insecticide or fungicide. It also measured litter, animal populations, and the elemental content of ten biologically important elements in soils and decomposing litter. Results show considerable differences in the rates of decay and the agents and end products of decay which indicate that black water and white water formation are closely tied to the rate and type of decay and to basic soil types and their associated vegetation, except for the rediments in white water.