Effects of litter diversity on decomposition and biological colonization of submerged litter in temperate and tropical streams

Abstract

AbstractDetrital food webs of woodland streams depend on terrestrial litter input and, thus, are susceptible to changes in riparian cover. We assessed effects of litter species richness and quality on decomposition and associated biological communities in temperate deciduous forest and tropical rainforest streams. Three native litter species were incubated in each stream in all combinations (7 litter treatments, 3 richness levels) in coarse- (invertebrate access) and fine-mesh bags (no invertebrate access) and were sampled 5 times over 74 (temperate stream) or 94 d (tropical stream). Decomposition, and fungal biomass, sporulation, and species richness were measured for each treatment. Alnus glutinosa litter was incubated in both streams to assess effects of environmental and biological differences between streams on litter decomposition. Biological colonization (number of fungal species, fungal biomass) and activity (conidial production) were lower in the tropical than the temperate stream, despite its hi...