Nutrient hotspots through time: A field guide to modern and fossil taphonomy in east Tennessee

Hotspots represent the ephemeral introduction of nutrients into an environment, and occur in both the modern and geologic past. The annual deposition of deciduous leaves in temperate forests, tree falls, animal excrement, and vertebrate carcass deposition all result in the pulsed introduction of nutrients to an ecosystem. Hotspots are critical for providing limiting nutrients, including nitrogen and carbon, to be incorporated into soil microbial biomass and plant biomass. For vertebrate carcasses, following the release of labile compounds from soft tissues, bones are often left behind, and provide a more recalcitrant reservoir of organic carbon and nitrogen, phosphorus, calcium, and, in some environments, water, for micro- and macro-fauna. Taphonomy-the physical, chemical, and biological processes following plant or animal death-studied in modern systems can be used to interpret hotspot processes operating in the past. East Tennessee is a region where studies of modern and fossil vertebrate hotspots have provided new insights into taphonomy. This guide describes two hotspot localities in east Tennessee-the Miocene-aged Gray Fossil Site in Gray, Tennessee, and the Anthropology Research Facility (“the Body Farm”) at the University of Tennessee, Knoxville, a human decomposition experimental site. The goal of this interdisciplinary field guide is to provide a view of nutrient hotspots from their formation in the modern to their preservation over geologic time.