Our ability to understand biogeochemical cycles of carbon, nitrogen and phosphorus and other elements in aquatic ecosystems has evolved enormously thanks to advancements in in situ sensor and laboratory techniques and predictive models. The aim of this session is to demonstrate how this methodological advancement improves our understanding of coupled hydrological, biogeochemical and ecological processes in freshwater aquatic environments, streams, rivers, lakes, wetlands and estuaries, controlling the fate of organic matter, nutrients, sediments and other chemical substances. In particular, our session focuses on improving the characterization of the origins, delivery pathways, transformations and environmental fate of organic matter, nutrients and sediments in aquatic environments along with identification of robust numerical tools for advanced processing and modelling of biogeochemical data. As hydrological, biogeochemical, and ecological processes undergo accelerated change, this session welcomes also studies presenting approaches and tools to monitor, model, and predict water quality and sensitivity of aquatic ecosystems to global change and human disturbances.