[1] Migrating bed forms strongly influence hydraulics, transport, and habitat in river environments. Their dynamics are exceedingly complex, making it difficult to predict their geometry and their interaction with sediment transport. Acoustic instrumentation now permits high-resolution observations of bed elevation as well as flow velocity. We present a space-time characterization of bed elevat...

Features extracted from echosounder bottom returns are compared with the ground truth in a North Sea survey area. The ground truth consists of 50 grab samples for which the grain size distribution, and the gravel and shell contents were determined. Echo envelopes are analysed for two single-beam echosounders, operated at frequencies of 66 and 150 kHz. It is shown that a set of six energetic, st...

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...

We analyzed the characteristics of red soils that are often considered collapsible soils. In this study, we examined depositional environment and lithologic characteristics, stratigraphy, conducted mechanical sieve, X-ray fluorescence, X-Ray diffraction, scanning electron microscope, fluorescence analyses optically stimulated luminescence dating. The samples were collected from gravel pits to e...

This study evaluates the performance of horizontal subsurface flow constructed wetland (HSSF-CW) for the removal of chlorinated resin and fatty acids (RFAs) from pulp and paper mill wastewater. The dimensions of the treatment system were 3.5 m x 1.5 m x 0.28 m with surface area of 5.25 m, filled with fine sand and gravel. The cell was planted with an ornamental plant species Canna indica. The r...

This paper deals with the issue of financing technology investments. Specifically, it concerns the process of loading and transportation of sand and gravel. The research was conducted through a questionnaire survey. The main objective of this paper is to identify financing sources used for the process of loading and transportation of sand and gravel in selected companies. Another objective was ...

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...

Given a choice of habitats in a laboratory experiment, whiting Merlangius merlangus preferentially spent most time over sand, then gravel and least time over a habitat with emergent structures. The introduction of a predator stimulus increased the preference for the sand habitat for large whiting, whereas small whiting had an increased preference for the habitat with emergent structures. # 2004...

Sediment transport, one of the key processes of river systems, is altered or stopped by dams, leaving lower river reaches barren of sand and gravel, both of which are essential habitat for fish and macroinvertebrates. One way to compensate for losses in sediment is to supplement gravel to river reaches below impoundments. Because gravel addition has become a widespread practice, it is essential...

Liquefaction is one of the major catastrophic geohazards which usually occurs in saturated or partially sandy silty soils during a seismic event. Evaluating potential liquefaction risks seismically prone area can significantly reduce loss lives and damage to civil infrastructures. This research mainly focused on earthquake-induced risk assessment based Potential Index (LPI) values at different ...