Author(s): Lydia Seitz; Silke Wieprecht; Markus Noack
Keywords: No Keywords
Abstract: The porosity of river bed material is an essential parameter to describe not only sediment transport processes but also the habitat conditions for many aquatic species. However, common methods for in-situ determination of porosity of river bed material are time-and effort-consuming. The objective of this study is to assess a new approach for the determination of porosity of frozen sediment samples. The method is based on volume determination by applying Structure-from-Motion with Multi View Stereo (SfM-MVS) to estimate a 3D volumetric model based on overlapping imagery. The developed method is applied for a wide range of different sediment mixtures and compared to the most commonly applied water replacement method (WRM). The SfM-MVS-method performed well in determining volumes and porosities of the sediment samples (r=0.998). In addition, the effort in the field can be reduced substantially. Hence, this method represents a novel and innovative approach to improve in-situ measurements of porosity.