Hydraulic mobility of aquatic insect (Trichoptera) bioconstructions and incorporated sediments
Mason, R.J., Rice, S.P., Johnson, M.F., Wood, P.J., Vettori, D. (2022). Hydraulic mobility of aquatic insect (Trichoptera) bioconstructions and incorporated sediments. NERC EDS Environmental Information Data Centre. https://doi.org/10.5285/cce26277-0b17-4c25-aa08-dd1486f89d9b
Data comprise resistance of aquatic bioconstructions (Trichoptera cases), and the loose sediment they were built from, to hydraulic forces measured in a hydraulic flume. S1_Velocimetry_data contains the output after post-processing the acoustic Doppler velocimetry data for each flow stage. This includes the mean and SD of velocity (m/s) for each direction (U – downstream, V – vertical and W- cross stream), the quality of the data recorded by the ADV (Signal to noise ratio and correlation) and calculated values of turbulent kinetic energy and bed shear stress. An explanation of each variable and units are included in the file. S2_Case-grain-size-distribution_data contains the grain size distributions for each caddisfly case obtained by sieving the case sediment. Includes the mass of sediment in half phi size intervals from 0.063 mm to 8 mm diameter. An explanation of each variable and units are included in the file. S3_Entrainment_data contains the percentage of sediment entrained during each flow stage (1-11). Percentage of sediment measured using photography of sediment remaining on the measurement platform. An explanation of each variable and units are included in the file. S4_Case-and-entrainment-threshold_data contains the caddisfly case characteristics (mass and a,b&c axes), critical entrainment thresholds and general movement data for each case and loose sediment. An explanation of each variable and units are included in the file.
We undertook a hydraulic flume experiment to quantify the effect of caddisfly case construction on sediment transport in rivers. The cases of three species were considered; two that construct different styles of tubular case (Potamophylax latipennis and Sericostoma personatum) and one that builds a domed case (Agapetus fuscipes). We compare the bed shear stress required to transport (1) empty caddisfly cases and (2) individual sediment particles following disaggregation from the case. Cases and sediment were placed in the centre of the flume and hydraulic force increased through 11 flow stages. The amount of sediment eroded at each flow stage was measured using analysis of photographs taken at each stage. Flume experiments were conducted between 20th August and 20th September 2019 and caddisfly collected on 17th June and 18th August 2019.
NERC EDS Environmental Information Data Centre
Aquatic insect bioconstructions modify fine-sediment entrainment and mobility. Richard J Mason, Stephen P. Rice, Matthew Frederick Johnson, Paul Wood, Davide Vettori. 2021