Water molds (see: Fungi) important to the cycling of energy through aquatic ecosystems. The breakdown of leaf material in the freestone river is highly dependent on this group of fungi. There is a succession of species of hyphomycetes during the decaying process, which may take the better part of a year. The progression of fungal species onto the surface of a given leaf is specific to the species of leaf being colonized, and probably specific to the place along the gradient of the river, as well.

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