Soil Microbiome

This chapter examines the soil microbiome as a foundation of terrestrial ecosystems, emphasizing its remarkable diversity and essential roles in natural, agricultural, and polluted environments. It introduces major microbial groups in soil – bacteria, archaea, fungi, protists, and viruses – and explains how their interactions support nutrient cycling, carbon turnover, organic matter decomposition, and methane regulation. The chapter describes how soil properties, vegetation, climate, and disturbance shape microbial communities, generating strong biome-level variation, and unique adaptations in extreme environments. It also highlights how global change, land-use intensification, and pollution alter microbial composition, network complexity, and functional resilience, reinforcing the need for conservation and baseline assessments. Further sections examine how agricultural practices and contamination by hydrocarbons and heavy metals reduce microbial diversity while selecting specialized degraders or tolerant taxa, with implications for soil health, food production, and One Health. Finally, the chapter presents modern omics and cultivation tools that reveal microbial functions and enable targeted strategies such as biostimulation and bioaugmentation to guide restoration and bioremediation.