Syntheses of decomposition and respiration responses across space and time

PROJECT SUMMARY

Changes in climate may alter the delicate balance between carbon uptake and release, with potentially strong negative effects on the global climate. Organic carbon decay starts with the decomposition of fresh, relatively labile material, which is partly stabilized into more recalcitrant compounds. In the third stage of decomposition, soil organic material is respired at much slower intrinsic rates. Across the world, standardized methods are used in climate change experiments (e.g. ITEX open-top chambers, snow fences). Besides vegetation changes, decomposition (e.g. Tea Bag Index) and soil carbon respiration are increasingly measured in these experiments. Such standardized, global/arctic approaches provide unique opportunities for meta-analyses. This postdoc project therefore aims to investigate how climate warming affects the three sequential phases of organic carbon decomposition on a regional (arctic) to global scale, and compare the importance of direct and indirect (vegetation, microbial) mechanisms.