TocAqua

Background & goal

The overarching goal of the TocAqua project (Transformation of organic carbon in the terrestrial-aquatic interface) is to understand the regulation of organic carbon (OC) transfor-mation across terrestrial-aquatic interfaces from soil, to lotic and lentic waters, with emphasis on ephemeral streams. Within the project we target the effects of (1) OC quality and priming, (2) stream sediment properties that control the advective supply of hyporheic sediments with oxygen and nutrients, and (3) the water regime. The responses of sediment associated metabolic activities, C turn-over, C-flow in the microbial food web, and the combined transformations of terrestrial and aquatic OC is quantified and characterized in complementary laboratory and flume experiments. We combined tracer techniques to assess advective supply of sediments, respiration measurements, greenhouse gas flux measurements, isotope labelling, and isotope natural abundance studies. Our studies contribute to the understanding of OC mineralization and thus CO2 emissions across terrestrial and aquatic systems. A deeper knowledge of OC-transformation in the terrestrial-aquatic interface is of high relevance for the modelling of carbon flow through landscapes and for the understanding of the global C cycle.

Publications

Fabian J., Zlatanovic S., Mutz M., Premke K. (2017) Fungal-bacterial dynamics and their contribution to terrigenous carbon turnover in relation to organic matter quality. ISME J doi: 10.1038/ismej.2016.131

Zlatanovic S., Fabian J., Mendoza-Lera C., Woodward B., Premke K. and Mutz M. (in revision) Impact of periodic sediment shifts on benthic microbial activity. Water Resources Research