Dissolved organic carbon: Its characterization and its effects on emergent plant decomposition in freshwater wetlands (Typha angustifolia, Impatiens capensis, Sparganium eurycarpum)

Field and laboratory experiments were conducted to examine potential roles of dissolved organic carbon (DOC) in wetland plant decay. The experiments consisted of varying DOC source, form and concentration during the decay of Typha angustifolia and Impatiens capensis. In no instance did DOC significantly affect the rate of weight loss during decay. Similarly, in wetland field studies, manipulation of plant detritus such that labile and recalcitrant taxa (I. capensis and Sparganium eurycarpum versus T. angustifolia) were placed in close proximity did not result in significant differences during the decay of these taxa.; Although DOC did not affect decay, emergent plants are likely a source of labile DOC. In the laboratory, T. angustifolia and S. eurycarpum released high amounts of low-molecular-weight DOC (<1,000 da) during the initial stages of decomposition. The difference between the overall concentrations of DOC released by these two plants was significant; T. angustifolia samples leached two times more DOC than S. eurycarpum samples.