17In marine environments, sediments from different sources are stirred and dispersed, generating beds that 29showed that the sediment bed (or the underlying sand bed in the case of the layering experiment) stabilized with 30 increasing silt composition. The increasing sediment stability was defined by a shift of the initial threshold 31 conditions towards higher flow speeds, combined with, in the case of the mixed bed, decreasing erosion rates. 32Our results show that even extremely low concentrations of silt play a stabilizing role (1.4% silt (wt %) on a 33 layered sediment bed of 10 cm thickness). In the case of a mixed sediment bed, 0.18% silt (wt %, in a sample of

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Framework-forming cold-water corals provide a refuge for numerous organisms and, consequently, the ecosystems formed by these corals can be considered as impressive deep-sea biodiversity hotspots. If suitable environmental conditions for coral growth persist over sufficiently long periods of time in equilibrium with continuous sediment input, substantial accumulations of coral mound deposits consisting of coral fragments and baffled sediments can form. Although this conceptual approach is widely accepted, little is known about the prevailing hydrodynamics in their close proximity, which potentially affect sedimentation patterns. In order to refine the current understanding about the hydrodynamic mechanisms in the direct vicinity of a model cold-water coral colony, a twofold approach of a laboratory flume experiment and a numerical model was set up. In both approaches the flow dynamics around a simplified cold-water coral colony used as current obstacle were investigated. The flow measurements of the flume provided a dataset that served as the basis for validation of the numerical model. The numerical model revealed data from the vicinity of the simplified cold-water coral, such as the pressure field, velocity field, or the turbulent kinetic energy (TKE) in high resolution. Features of the flow like the turbulent wake and streamlines were also processed to provide a more complete picture of the flow that passes the simplified cold-water coral colony. The results show that a cold-water coral colony strongly affects the flow field and eventually the sediment dynamics. The observed decrease in flow velocities around the cold water-coral hints to a decrease in the sediment carrying potential of the flowing water with consequences for sediment deposition.

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The comprehensive understanding of increasingly complex global challenges, such as climate change induced sea level rise demands for interdisciplinary research groups. As a result, there is an increasing interest of funding bodies to support interdisciplinary research initiatives. Attempts for interdisciplinary research in such programs often end in research between closely linked disciplines. This is often due to a lack of understanding about how to work interdisciplinarily as a group. Useful practical guidelines have been provided to overcome existing barriers during interdisciplinary integration. Working as an interdisciplinary research group becomes particularly challenging at the doctoral student level. This study reports findings of an interdisciplinary group project in which a group of doctoral students and postdoctoral researchers from various disciplines faced the challenges of reconciling natural, social, and legal aspects of a fictional coastal environmental problem. The research group went through three phases of interdisciplinary integration: (1) comparing disciplines, (2) understanding disciplines, and (3) thinking between disciplines. These phases finally resulted in the development of a practical guideline, including five concepts of interactive integration. A reflective analysis with observations made in existing literature about interdisciplinary integration further supported the feasibility of the practical guideline. It is intended that this practical guideline may help others to leave out pitfalls and to gain a more successful application of interdisciplinarity in their training.