Author(s): Gabriel Spreitzer; Jon Tunnicliffe; Heide Friedrich
Linked Author(s): Heide Friedrich
Keywords: No Keywords
Abstract: Large woody debris (LWD), together with overhanging bank vegetation and large rocks are generally attributed as microhabitat ecosystem units that influence riparian vegetation and sedimentation processes. Especially for hydraulic flow conditions during extreme flood events, when most in-stream material is mobile, it is important to consider interactions of biotic (LWD) and abiotic (sediments) materials. For the investigation of LWD accumulations on channel formation processes we are introducing Structure from Motion (SfM) methodology for capturing both, sediment dynamics as well as LWD jam formation. A multi-camera array, consisting of off-the shelf cameras, has been design to capture high resolution images that can provide detailed information about shape and size of a debris accumulation and volume dynamics of bedload activities. All tests and experiments are undertaken in a custom designed, fully scaled river channel. A cart, with the installed multi-camera array, running on rails at the top of the flume, ensures high quality data collection. Benefits of using SfM in the laboratory are guided by being low cost and allowing fast data collection, in contrast to a commonly used technology, such as laser scanning. Ultimately, the aim of our work is to gain a better understanding of biotic/abiotic interaction processes in stream systems, to enhance freshwater ecosystem management.