Microsensors, including a recently developed NO3(-) biosensor, were applied to measure O(2) and NO3(-) profiles in marine sediments from the upwelling area off central Chile and to investigate the influence of Thioploca spp. on the sedimentary nitrogen metabolism. The studies were performed in undisturbed sediment cores incubated in a small laboratory flume to simulate the environmental conditi...

Previous studies have hypothesized that wave-induced drag forces may constrain the size of intertidal organisms by dislodging or breaking organisms that exceed some critical dimension. In this study, we explored constraints on the size of the articulated coralline alga Calliarthron, which thrives in wave-exposed intertidal habitats. Its ability to survive depends critically upon its segmented m...

The endangered freshwater pearl mussel (Margaritifera margaritifera), one of the longest-lived invertebrates, are threatened globally. Scotland, UK, remains a stronghold, however even here the population is declining due to factors such as habitat degradation, pollution and pearl fishing. The study comprised two parts: field surveys of glochidia infection of host salmonid fish, and a novel labo...

PREMISE OF THE STUDY Intertidal macroalgae must resist extreme hydrodynamic forces imposed by crashing waves. How does frond flexibility mitigate drag, and how does flexibility affect predictions of drag and dislodgement in the field? METHODS We characterized flexible reconfiguration of six seaweed species in a recirculating water flume, documenting both shape change and area reduction as fro...

Background: The stabilization of fine sediments via biofilms (‘biostabilization’) has various economic and ecological implications but is presently unaddressed within lotic waters. To investigate natural biofilm growth and functionality in freshwater sediments under controlled boundary conditions, a unique mesocosm was constructed that combines established know-how from engineering and natural ...

The influence of woody debris on channel morphology and aquatic habitat has been recognized for many years. Unlike sediment, however, little is known about how wood moves through river systems. We examined some dynamics of wood transport in streams through a series of flume experiments and observed three distinct wood transport regimes: uncongested, congested and semi-congested. During unconges...

Distributed Information Flow Control (DIFC) is a systemlevel security mechanism that can simplify program security but requires that a programmer supply policy code in any programs it helps to secure. Writing this policy code is not a simple matter, and is thus likely to consume significant programmer attention and introduce bugs. Thus do we implement Boat, a means to simplify DIFC programming....

This paper presents the new boundary condition implemented in the LNEC (Laboratório Nacional de Engenharia Civil) SPH (Smoothed Particle Hydrodynamics) numerical model based on the SPHysics model and on a standard SPH formulation: This piston-type wave-maker now includes dynamic wave absorption and allows the simulation of a semi-infinite flume. Verification of the active wave-maker absorption ...

This study was conducted to identify the characteristics and mobility of debris flows analyze performance a berm as flow mitigation measure. The velocity, depth, Froude number, resistance coefficients, ratio were accordingly determined using results flume tests. To influence berm, for straight channel test without compared with those single-berm test. velocity observed increase increasing slope...