We used pre- and post-restoration channel surveys of the Donner und Blitzen River, Oregon, to evaluate the effects of grade-control structures on channel morphology and baseflow habitat conditions for native redband trout and other aquatic biota. Six years after installation, we found that the channel had a smaller proportion of riffles and pools and less gravel substrate, combined with an incr...

Cohesive particulate flows play an important role in environmental fluid dynamics, as well a wide variety of civil and process engineering applications. However, the scaling laws, constitutive equations continuum field descriptions governing such are currently less understood than for their non-cohesive counterparts. Grain-resolved simulations represent essential tool addressing this shortcomin...

Recent work has shown that muddy sediments are elastic solids through which animals extend burrows by fracture, whereas non-cohesive granular sands fluidize around some burrowers. These different mechanical responses are reflected in the morphologies and behaviours of their respective inhabitants. However, Armandia brevis, a mud-burrowing opheliid polychaete, lacks an expansible anterior consis...

A re®ned three-dimensional layer-integrated model to predict accurately salt and cohesive sediment transport in estuarine waters is described herein. A splitting algorithm has been used to split the three-dimensional transport equation into a horizontal twodimensional equation and a vertical one-dimensional equation due to the di€erent length scales. An additional source term associated with th...

Breaching of earthen or sandy dams/dunes by overtopping flow and waves is a complicated process with strong, unsteady flow, high sediment transport, and rapid bed changes in which the interactions between flow and morphology should not be ignored. This study presents a depth-averaged two-dimensional (2D) coupled flow and sediment transport model to investigate the flow and breaching processes w...

The objective of the present research is to explore the causes of microventing, a phenomenon generally occurring in cohesive sediments during their deposition and consolidation. Microvents are characterized by volcano-like formations, remnants of the expulsion of fluid and sediment along a vertical channel through the sediment layer. The size of these vent formations ranges from the order of mi...

The discovery of bacteria capable of anaerobic ammonia oxidation (anammox) has generated interest in understanding the activity, diversity, and distribution of these bacteria in the environment. In this study anammox activity in sediment samples obtained from the Inner Harbor of Baltimore, Md., was detected by (15)N tracer assays. Anammox-specific oligonucleotide primer sets were used to screen...