Prediction of Glossosoma biomass spatial distribution in Valley Creek by field measurements and a three‐dimensional turbulent open‐channel flow model

Abstract

The fluid flow environment associated with high Glossosoma abundance is predicted by largeeddy simulation of a natural turbulent open-channel flow. The spatial distribution of Glossosoma was depicted by high resolution physical variables described by fluid flow and streambed topography. Variogram analysis of the streambed topography revealed a characteristic length scale of the streambed of the order 0.2 m over which bed roughness height was correlated. Flow simulation output was spatially and temporally averaged over the streambed characteristic length scale and linked to Glossosoma spatial density. A dimensionless scaling relationship between Glossosoma spatial distribution and streamwise velocity averaged in the longitudinal and transverse direction, spatial velocity fluctuation, and spanwise vorticity from the computational fluid dynamics simulation output explained 79% of the variation in observed dimensionless Glossosoma spatial density. The analysis demonstrated that computational fluid mechanics and high resolution bed topography could be instrumental in predicting benthic macroinvertebrate spatial distribution in streams and rivers.

Life in turbulent flows: interactions between hydrodynamics and aquatic organisms in rivers

“…This may partly explain why aquatic communities (e.g., macroinvertebrates) appear to ‘map’ onto visually identifiable geomorphic units in rivers (e.g., riffles, pools, and cascades), while the hydraulics of those units have been difficult to define . Direct consideration of turbulence has been shown to add discriminatory power when exploring habitat preferences and distributions of both fish and invertebrates, illustrating the potential benefits of achieving better integration of ‘hydrodynamics into ecohydraulics.’ The parameters discussed in this paper in relation to the IPOS framework constitute a wide‐ranging portfolio of turbulence properties. These range from simpler time‐averaged measures such as turbulent kinetic energy and Reynolds stresses, to analysis in the time and frequency domains, to the extraction of vortex characteristics within a Lagrangian frame of reference.…”

“…For example, the presence of vegetation profoundly modifies the mean and turbulent properties of flow, 20 while the direct consideration of turbulence has been shown to add explanatory power when assessing habitat preferences of fish 21 and invertebrates. 22 In spite of this, there remains a disconnect between standard approaches to habitat assessment (which often rely on visual observation and/or averaged flow properties e.g., River Habitat Survey, Index for the assessment of fluvial habitat in Mediterranean rivers [23][24][25] ) and detailed investigation of hydrodynamics. This results in a lack of understanding of the links between turbulence and aquatic organisms at the 'mesoscale' of rivers 26 where habitat assessment and restoration tends to be focused.…”

Metacommunity patterns across three Neotropical catchments with varying environmental harshness

“…The local environment is known to strongly influence species distribution in temperate streams (e.g. Statzner et al, 1988;Hart & Finelli 1999, Lamouroux, Poff & Angermeier, 2002 and is the basis of most habitat models predicting the occurrence of invertebrate and fish species (Lamouroux et al, 2015;Morris et al, 2015). With respect to tropical streams (including our Bolivian streams), several studies have shown the importance of physical variables for community composition and diversity (i.e.…”

The zoogeomorphology of case‐building caddisfly: Quantifying sediment use

“…Glossosomatidae cases are built from sediment particles accessible to them on the bed surface (Marchant, ; Becker, ; Statzner, ; Hansell, ) and they may therefore have a disproportionate effect on sand availability at the bed surface. In particular, Glossosomatidae usually reside on the exposed upper surfaces of larger gravel particles where the flow of water facilitates respiration (Figure ; Nijboer, ; Becker, ; Morris and Hondzo, ; Morris et al ., ). Glossosomatidae therefore redistribute surface particles vertically, potentially increasing the exposure of constituent sand grains by transporting them from interstitial spaces and sheltered patches onto the upper surfaces of larger cobbles.…”