Soil biology is a branch of soil science that focuses on the study of the living organisms found in soil, including bacteria, fungi, protozoa, nematodes, and earthworms. These organisms play a crucial role in the health and fertility of soil by decomposing organic matter, cycling nutrients, and improving soil structure. Research in soil biology seeks to understand the interactions between these organisms and their environment, as well as their impact on plant growth, soil quality, and overall ecosystem functioning. This area of study is important for sustainable agriculture, environmental conservation, and biodiversity preservation.