What Are Soils? -- Microbial Diversity in Soils -- Microorganisms and Soil Genesis -- Role of Microorganisms in Wear Down of Rocks and Minerals -- Humification and Mineralization in Soils -- Importance of Microorganisms for Soil Aggregation -- Microorganisms and Biogeochemical Processes in Soils -- Microbial Energetics in Soils -- Role of Microorganisms in Carbon Cycling in Soils -- Contributio…