Fluxes of dissolved carbon dioxide and inorganic carbon from an upland peat catchment: implications for soil respiration

Abstract

This study uses long-term water chemistry records for a circum-neutral peat stream to reconstruct a 7-year record of dissolved CO2 and DIC flux from the catchment. Combining catchment flux with a knowledge of in-stream metabolism and gas evasion from the stream surface enables an estimate of the dissolved CO2 content of water emerging from the peat profile to be made; furthermore, these can be used to estimate soil CO2 respiration. In this way multi-annual records of CO2 production can be reconstructed, and therefore inter-annual controls on production examined. The results suggest that:(i) Stream evasion of CO2 within the catchment varied between 80 and 220 g C/m of stream/yr, while in-stream metabolism produces between 1.0 and 2.9 g C/m of stream/yr;