Liu, Chang2024-07-242024-07-242023-04https://hdl.handle.net/11299/264264University of Minnesota M.S. thesis. April 2023. Major: Land and Atmospheric Science. Advisor: Satoshi Ishii. 1 computer file (PDF); v, 49 pages.The invasion of non-native earthworms may drive significant changes to the local soil environment. Previous research shows that invasive earthworms can affect the soil physical and chemical properties and soil microbial activity. The changes of soil microbial community structures are strongly relevant to soil health and soil biodiversity. In research conducted near a hardwood forest at Northern Minnesota, it was found that earthworm invasion disrupts the soil microbial species diversity and shifted the community structure (Jang et al., 2022). Learning the fact that there are multiple other places formerly glaciated are under earthworm invasion, this study aims to extend the previous research to a global level. The approach of this study is to conduct 16S rRNA gene amplicon sequencing to investigate how the structure of microbial species are affected by non-native earthworms at earthworm-invaded sites including Alaska, Sweden and mesocosm study. Results from this study will lead to a greater understanding of earthworm dynamics and their impact on the broader soil community and carbon dynamics. This study uses 16S rRNA gene amplicon sequencing to have a comprehensive view of the soil microbial communities affected by earthworm invasion. Soil samples were collected at the study sites and soil DNA were extracted. The samples were sequenced for downstream analysis. The objective of this study was to examine the effects of earthworm invasion on the soil microbial community structure, and it was hypothesized that the earthworm-invaded soils would have different soil microbial community structures compared to non-invaded sites. The study found that there are differences in soil microbial communities depending on the extend how the soil was invaded by earthworms. The results are significant to understand the soil microbial activities, provide suggestions om regulation of earthworm invasion, and maintenance of soil health.enearthworm invasionforest soilsThesis or Dissertation