Numerous studies have examined qualitative shifts in leaf litter composition in the early to middle stages of decomposition. (Suberkropp, Godshalk and Klug 1976, Petersen and Cummins 1974, Findlay and Arsuffi 1989) which have shown that changes in leaf species and composition lead to marked differences in microbial processing rates (Suberkropp and Klug 1976) and that leaf and woody debris decomposition rates are related to both litter C:N and extracellular enzyme activities (Taylor et al. 1989, Sinsabaugh et al. 1992, Sinsabaugh and Linkins 1993). Since most organic matter moves through streams as fine particulate organic matter (FPOM) (Sinsabaugh et al. 1992) it is a potentially important link between terrestrial and aquatic environments. Although there is increasing interest in understanding FPOM dynamics, there have been few studies of factors influencing stream sediment FBOM chemical or microbial characteristics.
Bruce A. Caldwell, Heather L. Bonin, Robert P. Griffiths
The purpose of this study was to examine the fundamental relationship between FBOM nutrient availability, or substrate quality, and microdecomposer activity and to investigate the link between organic matter inputs and FBOM substrate quality. To this end, we compared the qualitative characteristics of FBOM from streams flowing through stands with riparian zones dominated by coniferous, deciduous (red alder) or herbaceous vegetation at two elevations for one year.