How microbiome predator–prey interactions shape litter decomposition

When plants and leaves fall to the ground, they slowly break down and become part of the soil. This process, called litter decomposition, is essential for healthy ecosystems because it helps recycle nutrients and supports plant growth. While bacteria and fungi are known to drive this process, much less attention has been given to the organisms that prey on them. This thesis studies tiny soil animals called protists and nematodes, which prey on microbes. Through laboratory experiments and a year-long field study, the research shows that these predators can shape how fast plant litter breaks down. Their effects depend on their species, size, and the type of litter involved. Overall, this work shows that interactions between soil organisms matter greatly for ecosystem health and should be included when we study soil, carbon cycling, and environmental change.