Download Biodiversity and ecosystem function within leaf

Jake Lanion Snaddon
Biodiversity and ecosystem function within leaf-litter accumulations in Sabah,
Malaysia.
Summary
Leaf-litter decomposition is one of the most important terrestrial ecosystem
processes. Even though the last decade has seen biodiversity and ecosystem
function studies emerge as one of the major topics in ecology, little is known about
the affect of biodiversity on decomposition. This thesis focuses on the relationship
between biodiversity and decomposition, utilising leaf-litter accumulations within
bird’s nest ferns as natural microcosms.
The value of bird’s nest ferns as a litter-trapping system was investigated within the
primary forest at Danum Valley Field Centre. The ferns were shown to trap and
retain leaf litterfall efficiently. The quantity of litter held per area of fern and the rate
of litter decomposition within the ferns were comparable to those on the forest floor.
The bird’s nest ferns are therefore excellent natural microcosms in which to study
the effect of invertebrate and leaf-litter diversity on litter decomposition.
The influence of invertebrate diversity on litter decomposition was studied in fern
and forest floor habitats, across three forest types (primary forest, logged forest and
oil palm plantations). Invertebrate diversity, both at ordinal and species levels, was
not found to affect litter decomposition. Decomposition was also influenced by forest
type and habitat. Experimental manipulation of the leaf-litter diversity within bird’s
nest ferns did not show an effect on decomposition overall. However, within leaflitter mixtures a choosing effect occurred, with some litter species decomposing at
slower rates than they do in monocultures.
Fungal rhizomorph networks were assessed as an additional litter-trapping system
within the primary forest. These understudied litter-trapping systems were found to
retain larger quantities of leaf litter than the bird’s nest ferns, though the litter was
more dispersed throughout the forest understorey. The removal of the litter
associated with the fungal rhizomorph systems resulted in a significant decline in
invertebrate diversity and abundance, illustrating its importance to the invertebrate
community.