Riverine dominated marine depositional environments

Large river systems present key linkages between the atmosphere, continental climate (e.g., hydrology, erosion), and the oceans, reflecting a complex interplay that modulates coastal productivity, salinity, circulation patterns, and sedimentary depositional systems. High sediment load and riverine induced marine biological productivity generate one of the highest sediment accumulation rates in the marine realm. These marine archives provide unique possibilities to decipher past climate history on various time scales, from orbital to decadal and down to seasonal resolution. 

Here at the Paleoceanography Research Unit, our concerted efforts focus on the understanding of past land-ocean linkages using marine archives from sites off large river systems whose catchment areas range from tropical rainforests to polar regions.

 

We employ a multitude of tools for past climate reconstruction, such as sedimentological, micropaleontological, stable and radiogenic isotope, and geochemical proxy parameters as well as numeric modelling using GCM's. Major research objectives include:

• Characterization and quantification of fluvial input and assessment of continental weathering. 

• Reconstruction of freshwater discharge to provide insights into changes in precipitation in the drainage basins through time. 

• Reconstruction of riverine-induced productivity changes and its impact on the ecosystem of different marine zoo- and phytoplankton groups. 

• Understanding riverine fresh water induced changes in surface water stratification and its effect on circulation patterns. 

• Evolution of tropical watersheds and continental hydrography during greenhouse times; nutrient fluxes and their impact on the marine realm.

 

River systems currently studied:

Lena
Mississippi
Orinoco 
Nildelta