Leaf Litter Decomposition as a Contributor to Ecosystem Service Provision

Leaf litter decomposition supports the provision of numerous ecosystem services—that is, the benefits nature provides to humans—through its contribution to the reduction and storage of organic materials that could negatively impact water supplies, and its support of the productivity of freshwater ecosystems. The magnitude of these services varies spatially, and with land use. Leaf litter decomposition contributes a large fraction of energy supporting production in small streams, and to downstream production through supplies of finer particles produced by consumers. Decomposition results in storage of carbon as biomass in biological communities, and reduces the amounts of organic materials that could impact water quality downstream. Changes in water quality that result from decomposition can also influence the aesthetic and recreational value of waterways. Land use can influence decomposition, for instance elevated nutrient concentrations can result in higher decomposition rates, but high temperatures and sediment loads may diminish those rates. Changes in the rates of such ecosystem functions may be proportional to changes in the associated benefits provided to humans. While decomposition is a key ecosystem function that can contribute to the provision of numerous services, there are few estimates of the human value of this process in freshwaters.