The isotopes and biomarker approaches for identifying eroded organic matter sources in sediments: A review

Ascertaining the fate of eroded OM is critical for our understanding of the role of soil erosion in global and local carbon cycles on earth's system. In this review, we compiled critical information on isotopes and molecular biomarker approaches that are widely applied to identify sources of eroded OM. We highlight the benefits and shortcomings of each approach and provide a comparison of the different approaches to determine their suitability for application under different environmental conditions and land use. We find that the compound-specific stable isotope signature of biomarkers are superior in their potential to provide plant-specific information on compounds that are likely to be preserved during transport and may at least initially resist diagenetic alterations. Molecular biomarkers provide an ability to reconstruct paleoenvironmental and paleoclimatic conditions due to their capacity to concurrently identify a wide range of sources from a mixture; while stable isotope analyses are also reliable tool to complement the biomarker's limitations for quantifying source identification.