TY - JOUR T1 - Relic DNA is abundant in soil and obscures estimates of soil microbial diversity JF - bioRxiv DO - 10.1101/043372 SP - 043372 AU - Paul Carini AU - Patrick J. Marsden AU - Jonathan W. Leff AU - Emily E. Morgan AU - Michael S. Strickland AU - Noah Fierer Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/03/17/043372.abstract N2 - It is implicitly assumed that the microbial DNA recovered from soil originates from living cells. However, because relic DNA (DNA from dead cells) can persist in soil for weeks to years, it could impact DNA-based analyses of microbial diversity. We examined a wide range of soils and found that, on average, 40% of prokaryotic and fungal DNA was derived from the relic DNA pool. Relic DNA inflated the observed prokaryotic and fungal diversity by as much as 55%, and caused misestimation of taxon abundances, including taxa integral to key ecosystem processes. These findings imply that relic DNA can obscure treatment effects, spatiotemporal patterns, and relationships between taxa and environmental conditions. Moreover, relic DNA may represent a historical record of microbes formerly living in soil. ER -