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

生态学家长期以来一直对控制陆地生态系统中植物物质分解的因素感兴趣。分解是植物吸收的养分在生态系统中循环利用的主要过程。虽然对分解的物理环境控制已经进行了很好的研究，但对以腐质为食的动物之间的相互作用或这种相互作用如何影响分解所知相对较少。大型的营养动物，如蚯蚓、千足虫和母猪虫，可能会改善小型土壤动物如线虫和弹尾虫的食物质量。本项目探讨了一种常见的母猪虫、坡瓷虫和土壤动物之间的相互作用。在本研究系统中，坡瓷菌显著增加了植物凋落物的分解。母猪虫可能加速植物凋落物与土壤的结合，并使依赖这种碎屑流入的土壤动物受益。母猪取食虫也可能通过提高腐质养分含量和促进微生物定植而有利于土壤腐质动物。这项工作将通过实地和实验室实验来验证这些假设，并在自然土壤群落和受控实验室实验中证明坡瓷菌对土壤动物的总体影响。这项研究将有助于更好地理解碳是如何通过分解者食物网循环的，以及物种之间的相互作用如何导致分解率的变化。该项目还将支持一名博士生的论文研究。

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.