Small-scale turbulent motions in the water column form a crucial component of the sediment transport process, providing both the critical stress for mobilization and the energy for distributing suspended matter throughout the water column. These processes will be investigated in detail in WP 2.1 with the help of an extensive field program, and a high-resolution numerical model of the Western Baltic, focusing on the relation between turbulence, re-suspension, and transport processes in the transition region between the well-mixed coastal zone and the stratified interior. Measurements will include ship-based observations with vessel-mounted current meters and a shear-microstructure profiler that yields nearly full-depth profiles of stratification, turbidity, oxygen, and micro-scale shear from which turbulent diffusivities can be inferred. Specialized bottom landers will be deployed for extended periods for the analysis of near-bottom turbulence and SPM structure in the water column. Comparison with discrete filter probes will allow us to calibrate SPM concentrations estimated from turbidity sensors and from the acoustic backscatter of the moored current profilers. Field data from different campaigns will be finally be used to validate the numerical turbulence/transport model, and assess re-suspension and transport rates, as well as transport pathways in the study area.