A simple method for in-situ assessment of soil respiration using alkali absorption.

Lacking knowledge about the spatial heterogeneity of heterotrophic soil respiration (R h ) hampers the prediction of larger-scale soil CO 2 efflux in patchy landscapes. The aim of this study was to establish a cost-efficient method for the rapid and simultaneous assessment of cumulative heterotrophic soil respiration (CO 2 ) at different sample spots. For this purpose, we adapted the laboratory-based, fully-automated Respicond VIII respirometer (Respicond) to detect CO 2 emission under field condition, installed the device in two temperate grasslands, and compared the R h flux data with those obtained using the so-called dynamic chamber method with infrared gas analyzers (IRGA). The results revealed good agreement between both R h measurements (Slope = 0.89, R 2 = 0.99). We conclude that adapting the Respicond for detection of CO 2 under field conditions is principally feasible, thus providing a new tool for the simultaneous assessment of CO 2 fluxes from different soil ecosystems. [ABSTRACT FROM AUTHOR]