1. Introduction

Soil microorganisms play a vital role in soil functions influencing the biogeochemical cycle, soil fertility, plant health, and aboveground ecosystems. The soil harbours more diverse communities of microorganisms than any other environmental component. We have a narrow understanding of how microbial diversity regulates soil functioning and in turn affects ecosystem sustainability. Studies of soil microorganism-mediated processes responsible for soil functions have largely been neglected. With increasing pressure on soils to meet the demands of the rapidly increasing human population for food, fodder, fibre, biofuel, timber, clean water, etc., it is imperative that research in soil microbiology focuses on the structure and functions of the soil microorganisms to delineate microbe-mediated soil processes and optimise them for enhanced production and better soil function. Moreover, soil also acts as a reservoir of carbon because its soil carbon sequestration potential helps in reducing atmospheric CO₂ levels. However, it is believed that warming climate conditions in the changing climate can negatively affect the carbon sequestration potential and other functions of the soil. To negate the climate impacts arising from increased CO₂ emissions from the soil, it is essential that we have a deep understanding of the processes of soil carbon storage. As the microbial activities in the soil largely regulate its functions, including soil carbon sequestration, it is important to gain deeper insights into the soil microbial world to address the issues of climate change and food security.