Microbial Diversity of Soil Ecosystems

This chapter reviews some of the most commonly used methods for assessing soil microbial diversity. It discusses the limitations of the various methods and elucidates the types of information that are and are not provided by assessments of soil microbial diversity. Early studies of soil bacterial diversity involved isolating and purifying the bacterial species occurring in the soil of interest via culture‐based methods and classifying the isolates according to species based on phenotypical characteristics. This approach can be used to assemble soil bacterial community surveys and to compare the species composition of communities from different sites or different experimental treatments. Fundamentally, to be aligned with classical considerations of biological diversity, surrogate measures of soil microbial diversity should be based on a delineation that varies in parallel with actual species diversity. An alternative indicator of variation in microbial diversity in soils involves determination of the diversity of phospholipid fatty acids.