DISSERTATION RESEARCH: The Role of Porcellio Scaber in a Litter Processing Chain

University Of California-Davis, Davis CA

Investigators

Abstract

Ecologists have long been interested in the factors that control the decomposition of plant matter in terrestrial ecosystems. Decomposition is the primary process through which nutrients taken up by plants are recycled in the ecosystem. Although the physical environmental controls on decomposition have been well studied, relatively little is known about interactions among the animals that feed on detritus or how such interactions affect decomposition. Large detritivores, such as earthworms, millipedes and sow bugs, may improve the quality of food available for small soil animals such as nematodes and springtails. This project examines the interaction between a common sow bug, Porcellio scaber, and soil fauna. Porcellio scaber dramatically increases the breakdown of plant litter in this study system. The sow bugs may accelerate incorporation of plant litter into the soil, and benefit soil animals that depend on such influxes of detritus. Sow bug feeding may also benefit soil detritivores by improving the nutrient content of detritus and facilitating of microbe colonization. This work will test these hypotheses with field and laboratory experiments and demonstrate the overall impact of Porcellio scaber on soil fauna in a natural soil community and in controlled laboratory experiments. This study will contribute to a greater understanding of how carbon is cycled through decomposer foodwebs, and how species interactions contribute to variation in decomposition rates. This project will also support the dissertation research of a doctoral student.