Thermal analysis of soil organic matter bioenergetics

摘要

Transformations of energy underpin most biogeochemical cycles on Earth as it has long been understood that the amount and types of energy available in an environment influence the rates of biological activity and the complexity of interactions in that ecosystem. Thermal analyses have and continue to play a growing role in the characterization soil organic matter (SOM) and other geologic materials. However, in recent years, there has been increasing interest in quantifying how energetics define soil ecosystems and control SOM turnover. Fundamentally, SOM stability depends on the balance of microbial bioenergetics between the input of energy needed to decompose it (i.e., activation energy; Ea) and the net energy gained (i.e., energy density; ED) from its decomposition. In this study, we demonstrate that the thermally derived bioenergetics (the relationship of ED and Ea) of SOM from a suite of experimental soils has the ability to provide information about relative differences in SOM chemical composition and stability.