In this session, conveners from the Isotopes in Geosciences, Biogeosciences, and Soil System Sciences program groups of the EGU joined forces. The aim is to bring together scientist from various backgrounds, but all devoted to the use of molecular and isotopic techniques in terrestrial ecosystem studies.

Relevant topics include, but are not limited to:
- Assessment of human impact on our environment (e.g., archeology, land use change, agricultural systems, elevated atmospheric CO2, black carbon)
- Organic matter dynamics (i.e. transformation, diagenesis, preservation, sequestration and transport)
- Reconstructions of paleo-environment and -climate
- Development of new molecular proxies or new applications of existing ones
- Proxies for/of microbial processes and communities (e.g., (ancient) DNA, PLFAs)

All lines of research mentioned here share a common root in that they require a detailed characterization of organic matter inputs and the transformation products of such inputs at the molecular level. This session aims to provide a platform for scientific discussion and exchange of ideas between different (sub)disciplines dealing with these topics, and includes both fundamental and applied research, and field-, laboratory as well as modeling studies.