A global database of soil respiration data

Soil respiration - R-S, the flux of CO2 from the soil to the atmosphere - is probably the least well constrained component of the terrestrial carbon cycle. Here we introduce the SRDB database, a near-universal compendium of published R-S data, and make it available to the scientific community both as a traditional static archive and as a dynamic community database that may be updated over time by interested users. The database encompasses all published studies that report one of the following data measured in the field (not laboratory): annual R-S, mean seasonal R-S, a seasonal or annual partitioning of R-S into its sources fluxes, R-S temperature response (Q(10)), or R-S at 10 A degrees C. Its orientation is thus to seasonal and annual fluxes, not shorter-term or chamber-specific measurements. To date, data from 818 studies have been entered into the database, constituting 3379 records. The data span the measurement years 1961-2007 and are dominated by temperate, well-drained forests. We briefly examine some aspects of the SRDB data - its climate space coverage, mean annual R-S fluxes and their correlation with other carbon fluxes, R-S variability, temperature sensitivities, and the partitioning of R-S source flux - and suggest some potential lines of research that could be explored using these data. The SRDB database is available online in a permanent archive as well as via a project-hosting repository; the latter source leverages open-source software technologies to encourage wider participation in the database's future development. Ultimately, we hope that the updating of, and corrections to, the SRDB will become a shared project, managed by the users of these data in the scientific community.