THE BREAKDOWN OF BURIED AND SURFACE-PLACED LEAF-LITTER IN AN UPLAND STREAM

The breakdown of buried leaves (Eucalyptus viminalis) was investigated using surface-placed and buried leaf packs in a riffle of the Acheron River, Victoria. Leaf packs buried to a depth of 10 cm were rapidly c olonized by invertebrates, with the total numbers of individuals and s pecies exceeding those on surface leaf packs. A larger proportion of l eaves in buried leaf packs was grazed in comparison with those on the surface, with the intensity of grazing also being higher for leaves in buried packs. Both surface and buried Leaf packs broke down rapidly w ith no significant difference in weight loss with time. The high level of breakdown of buried E. viminalis leaf litter observed in this stud y suggests that the hyporheos of Australian headwater streams may sign ificantly contribute to the decomposition of particulate organic matte r.