This thesis investigates the effects of agricultural soil amendments on the soil microbial community and associated soil nutrients to gain an understanding for the potential implementation of the amendments as practice to promote overall soil health. Study one explored soil fumigation (metam sodium, 1,3-dichloropropenene, and combination) amendments and the potential to recurve impacts fumigation has on the microbial community through cover crop planting (faba bean and winter pea mixture, mustard, radish, and wheat). Results from this study showed that metam sodium+1,3-dichloropropene application resulted in the most shifts in community abundance, with Planctomycetota, Acidobacteriota, and Verrucomicrobiota significantly decreasing (2.39%, 7.48%, and 1.01% to 1.95%, 5.42%, and 0.70%, respectfully). Regarding the eukaryotic population, the dominant phyla Ascomycota and Basidiomycota showed significant decreases with combination fumigation treatment, decreasing from 11.41% to 6.93% and 0.77% to 0.36%, respectfully. None of the cover crops resulted in changes in the microbial community following fumigation for either prokaryotic or eukaryotic populations.Study two researched anaerobic digestate as an organic fertilizer alternative and the effect application has on the soil microbial community. Results showed shifts in both prokaryotic and eukaryotic taxa. Proteobacteria and Firmicutes abundance increased from 18.0% to 19.1% and 4.95% to5.81%, respectfully, and Chloroflexi decreased from 6.72% to 5.82%. For the eukaryotic population, the abundance of Basidiomycota increased significantly with the application of digestate from 2.4% to 3.9%. The nutrient levels remained stable throughout the duration of the study, apart from total hydrogen which significantly decreased with digestate application from 1.10±0.50 wt% to 0.59±0.22 wt%.
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