Land-fjord interaction and the impact of changing sedimentation rates on fjord environments – an integrated study of Arctic sediment transport from land to sea

The SSF funded project “Sediment flux from source to sink – the Coastal Link” is an international, multi-disciplinary research project aiming at understanding and quantifying sediment distribution patterns in Svalbard fjordids. The current project (2016-2017) focuses on Kongsfjorden and Dicksonfjorden as representatives for glacially and non-glacially influenced fjord types. The impact of abiotic factors, including the impact of terrestrial run-off and freshwater discharge on marine ecosystems are highlighted as important topics where little is done, and which should be prioritized, in the reports defining the currents aims for the Ny Ålesund flagship programmes (Report Ny Ålesund seminar september 2015, Terrestrial Flagship Programme and Report Ny Ålesund Seminar 2015, Kongsfjorden flagship group). On a global scale high latitude data on sediment and nutrient fluxes to the fjords and eventually oceans are underrepresented in earth systems models (Russell, 2014). Previous studies of Svalbard fjords have typically been divided into either fjord or coastal studies, whereas links between coastal zone and sea floor records are few. This project is the first comprehensive coordination of the physical fjord- and coast research taking place in Svalbard and the first time such a significant part of this community is working together towards joint aims. Through sharing of infrastructure and resources we have been able to study the coastal dynamics, sediment volumes and fjord bottom distribution of sediments along two land- sea transects in Kongsfjorden and Dicksonfjorden. For Kongsfjorden the project includes a compilation of existing data as well as new studies of coastal dynamics and fjord bottom bathymetry and sediment sampling. For Dicksonfjorden no previous data existed from the coastal zone and the inner part of the fjord. Here we have carried out detailed mapping of the tidal delta and the sea floor in the inner fjord, hydrodynamic measurements and sedimentation in the tidal channels, coring onshore and offshore and sampling for foraminifera, nutrients and microbial abundances. Sediment accumulation rates are being assessed from 210Pb and 137Cs radionuclides. The aim is to calculate sediment volumes, fluxes and transport rates. The long-term aim is to develop a system for obtaining comparable datasets on annual – decadal time scales on land – sea interaction for Svalbard, including expansion of the current pilot project to other fjord types. To reach this goal a better integration with research in other disciplines is needed, in order to develop shared strategies and exploit possibilities to share infrastructure. It also requires a systematic collection strategy and a robust data sharing praxis with the users of such data including projects and networks coordinating ecosystem research but also earth system modelers for example. This presentation will provide an overview of the ongoing research and preliminary results and discuss the potential for collaboration with other scientists and disciplines.