Janna M. Barel

1 Introduction The breakdown of organic material is the result of several processes (e.g., leaching, fragmentation, bleaching, enzymatic hydrolysis) that comprise the process of decomposition. The relative importance of these processes can change over time and space, across litter types and material fractions within a given litter type, but they all result in loss of organic material from the original unit (e.g., a leaf).

1 INTRODUCTION Peatlands are the largest natural terrestrial carbon (C) store and critical to prevent and mitigate climate change (Charman et al., 2013; Helbig et al., 2020; Monier et al., 2013; Sand et al., 2015).