Decomposition Rates of Typha Spp. in Northern Freshwater Wetlands over a Stream-Marsh-Peatland Gradient

Abstract

Decomposition rates in wetlands vary with the composition of the biotic community and the physical and chemical environment. Variations in the process of decomposition in turn affect the overall rate of nutrient cycling within the wetland, affecting both primary productivity and general wetland health. This short-term study took place in northern New York within the Little Chazy River watershed. The effects of wetland factors including nutrient status, dissolved oxygen, and pH value on decay rate were measured over a freshwater stream-marsh-peatland gradient. Litterbags were utilized and collected weekly from three separate sites within or near the Altona Flat Rock ecosystem. Soil and water parameters, as well as colonization by macroinvertebrates, were studied in order to link decay rates with specific wetland characteristics. Decomposition rates for Typha spp. were evaluated using the change in dry biomass, and percent nitrogen content of the plant litter. Dry biomass reduction took place most rapidly in the stream site and least rapidly in the peatland site, while fluctuations of percent nitrogen content did not show a distinct trend. A high level of dissolved oxygen corresponded to a higher decay rate, while a low pH value corresponded to a lower decay rate.