Wetland soil organic matter composition in a Mediterranean semiarid wetland (Las Tablas de Daimiel, Central Spain): Insight into different carbon sequestration pathways

► Characterization of wetland sedimentary organic matter using CPMAS 13C NMR spectroscopy. ► Origin and mechanisms of accumulation of organic matter in semiarid wetlands. ► Use of molecular mixing model to elucidate organic matter composition.