approach of organic material anaerobic biodegradation and species of organic matter in sediment are discussed, and then a classifying method of the species is proposed on a new viewpoint. the pore water sediment oxygen demand (sod) numerical model in bottom sediment system is proposed originally, which differs from other advection-dispersion-sorption (ads) model in adding a sod-creating term. t...

abstract bottom rack intake is one of the most appropriate structures for diverting water in steep rivers. the problems of corrosion, deformity and clogging of the bottom racks in long term, inspires a new system of bottom intake in which a filled trench of porous media is replaced by the bottom racks. diversion of a specified amount of discharge through the porous media when void space in the ...

A quasi-three-dimensional suspended sediment transport model was developed and generalized to include combined wave-current effects to study bottom sediment resuspension and transport in southern Lake Michigan. The results from a threedimensional circulation model and a wind wave model were used as input to the sediment transport model. Two effects of nonlinear wave-current interactions were co...

The research aimed to assess the effect of bottom sediment on the content, bioaccumulation and translocation of heavy metals in maize biomass. The investigations were conducted in 2006-2007 as a pot experiment on light soil of the granulometric composition of weakly-loamy sand. The experimental design comprised 3 treatments: without sediment (I), a 5% sediment admixture (II) and a 10% sediment ...

Typhoon induced sediment warming has been proven important to coastal sound-field change in this study. It was observed that the temperature of the bottom waters off the coast of Qingdao increased by 5 °C after the passage of typhoon Damrey in 2012. Sediment warming due to bottom-water temperature increase was calculated and the change in sediment sound speed was estimated. Transmission loss (T...

The backscattering of sound by inhomogeneities of the ocean sediment may provide a remarkable effect on underwater acoustic wave propagation. It may also be used as a means of remotely estimating complicated sediment properties. In this paper, a theoretical model of acoustic waves backscattered from an inhomogeneous sediment is formulated based on the Born approximation. The model not only cont...

A study was carried out on the occurrence of chitinolytic bacteria inhabiting surface water, water above the sediment and bottom sediments of lakes: Jeziorak, Jeziorak Maty and Tynwald. The greatest amounts of them were found in demersal water and in bottom sediment surface stratum. However, the percentage share of chitinolytic bacteria proved greater in deep water (9.35%) than in bottom sedime...

The ability of internal tides to resuspend and advect sediment over continental shelfs and slope regions is investigated by applying an internal wave and sediment transport model. Numerical experiments are carried out, firstly, with the ratio of bathymetry and internal waves characteristics creating critical, subcritical, and supercritical conditions, and secondly, for an observed section of th...

The present study investigated contamination of polybrominated diphenyl ethers (PBDEs) in sediment and fish samples collected from rivers in Guiyu, China where electronic waste (e-waste) is recycled and disposed. PBDE congeners with mono-to hepta-brominated and deca-brominated substitutions were detected using (13)C(12) isotope dilution GC/MS/MS and GC/MS methods, respectively. The total PBDE c...