Abstract

In recent years we have learned a great deal about the sources and composition of organic matter preserved in soils and sediments.  However, our knowledge of the timescales over which organic carbon cycles within and between different reservoirs remains relatively poor.  Radiocarbon measurements on source-specific “biomarker” compounds provide a window into the dynamics of specific organic components encountered in complex environmental matrices and different biomarkers recovered from sediment samples have been found to exhibit remarkable age variability.  These observations yield information on rates at which organic carbon cycles through the environment, and on organic matter sources. In this presentation I will illustrate how ¹⁴C age relationships between organic components can be used to provide new information on transport and depositional processes that is crucial for interpretation of sedimentary records, as well as for development of accurate models of organic matter cycling in the contemporary environment.