|| 要旨トップ | 本企画の概要 |||日本生態学会第57回全国大会 (2010年3月，東京) 講演要旨|
It is well recognized that earthworm activity substantially mediates the microbial processes in soil nutrient dynamics. Other than earthworms, however, little is known about ecosystem functions of soil macrofauna. Millipedes from Xystodesmidae are common in central and southwestern Japan and sometimes dominate in biomass of soil macrofauna. Thus their impact on soil ecosystem functioning is expected. Here I show a study about the effects of the train millipede (Parafontaria laminata) on the soil microbial processes.
Feeding experiments revealed that the millipede stimulates microbial respiration and CH4 consumption in soil. Especially, CH4 consumption in soils was related to the feeding habit of the millipede; soil CH4 consumption increased when the adult of soil-litter mixed feeder was fed on soil and litter, while the larvae of soil feeder did not influence. Contrary, guts of the millipede emitted CH4 in anoxic condition, indicating presence of methanogenic microbes in the guts.
Another aspects of ecosystem function of the millipede is an increase of soil aggregation. Both of feeding experiment and field observation showed that the millipede increase large-size fraction of soil aggregate. C mineralization of the aged aggregates was lower than soil with disrupted aggregate structure, suggesting contribution for C accumulation in soil aggregates.