New uses for old tools: Reviving Holdridge Life Zones in soil carbon persistence research

Growing evidence suggests that climate classification facilitates the identification of zones that either agree or disagree with processes explaining soil organic carbon (SOC) persistence. Already forty years ago, Post et al. (1982) posited that the strict temperature and precipitation-based classification defining the Holdridge Life Zones (HLZ) provides a descriptive tool to guide our understanding of the heterogeneous distribution of global SOC stocks. Here we argue that this classification has the potential for describing SOC persistence by linking top-down and bottom-up approaches from different scales, which allows selection of individual regional relevancies necessary to manage and track the fate of our largest terrestrial carbon (C) reservoir.