Mixed sediment beaches are morphologically distinct from and more complex than either sand or gravel only beaches. Three digital imaging techniques are employed to quantify surficial grain size and bedload sediment transport rates along the mixed sediment beaches of Kachemak Bay, Alaska. Applying digital imaging procedures originally developed for quickly and efficiently quantifying grain sizes...

So far, few studies have focused on the concept of critical flow velocity rather than bed shear stress for incipient sediment motion. Moreover, mixtures (graded sediment) and shape uniform motion condition. Different experiments were conducted at a hydraulic laboratory University Guilan in 2015 to determine parameters The aim this study is conduct comparison between graded sediments, round angu...

A model is presented that simulates the effects of streamflow and sediment transport on survival of salmonid embryos incubating in spawning gravels in a natural channel. Components of the model include a 6-yr streamflow record, an empirical bed load-transport function, a relation between transport and infiltration of sandy bedload into a gravel bed, effects of fine-sediment infiltration on grav...

The effects of substratum particle size (cobbles, coarse gravel and medium-fine gravel) on recolonization by benthic macroinvertebrates after disturbance was investigated in small plots (0.05 m2) in the Finniss River, an intermittent stream in South Australia. Six weeks after flow resumed, the intermediate particle size (coarse gravel) supported the greatest densities of taxa and individuals. E...

We investigated the potential of using a 24-electrode resistivity imaging apparatus for rapid reconnaissance surveys for natural-aggregate accumulation. The surveys were first calibrated at sites with known geometry of sand and gravel layers, which showed that subsurface accumulation of coarse material was accurately resolved with both 2and 4-m electrode spacing. The inverted absolute resistivi...

Incubating salmonid eggs in streambeds are often threatened by deposition of fine sediment within the gravel. To relate sedimentation of spawning gravel beds to sediment transport, infiltration of fine sediment (<2 mm in diameter) into clean gravel beds, bed material size distributions, scour-fill depths, and sediment transport during 10 storm flow events were measured in three streams of north...

Stratification and estimated paleoflow conditions for valley-fill deposits suggest that Ogallala Group streams in western Nebraska were similar to modem streams of south-central Alberta. Ogallala stratification includes medium-scale (0.5 to 2. O m thick) trough crossbedded sand and gravel, tabular indistinctly horizontally bedded and imbricated gravel, and horizontally bedded sand and pebbly sa...

Laboratory scale studies were conducted to investigate the feasibility of Industrial by-products as potential alternative medium to conventional gravel in the drainage layer of leachate collection system as permeable reactive barriers (PRBs) for landfill leachate treatment. Industrial by-products were used to treat effectively the landfill leachate, which is an innovative in-situ remediation te...

Although environmental enrichment is known to improve laboratory rodent wellbeing and enhance scientific data collection, relatively little is known with regards to the type of enrichment that might be useful for zebrafish (Danio rerio). Therefore, this study explored if zebrafish displayed preferences for a range of enrichments, including substrates, artificial plants, combinations thereof and...