abstract bottom rack intake is one of the most popular structures used for diverting water in mountain region. corrosion and rotten problems of bottom racks inspire the introduction of a new system of bottom intake in which a porous media is replaced by the bottom rack. obviously, clogging and reduction of diverted discharge are the most important problems in this new system, too. in this paper...

the sexual maturation and spawning period of blood cockle in matang mangrove estuary was studied by naked eye and histological observations of the gonads from july 2010 to april 2011. the high spawning period was from november to february. however, at one station where bottom sediment exhibited a severe reduction in potential of −100 mv lower, immature individuals were common. these results sug...

Lake Sayram is an ancient cold water lake locating at a mountain basin in Xinjiang, China. The lake water is brackish, alkaline, unpolluted, and abundant in SO4(2-) and Mg(2+). The lacustrine ecosystem of Lake Sayram has been intensely investigated. However, profiles of the microbial communities in the lake remain largely unknown. In this study, taxonomic compositions of the planktonic and sedi...

In the long term, the main source of contaminants in the Housatonic River is the bottom sediments (both those in the river and in the floodplain). In this long term, environmental conditions will change with time and will be different than they are at present, especially because of and after remediation. For purposes of predicting water quality, it is therefore essential to accurately determine...

The adsorption of contaminants plays an important role in the process of their elimination from a polluted environment. This work describes the issue of loading environment with lead Pb(II) and the resulting negative impact it has on plants and living organisms. It also focuses on bentonite as a natural adsorbent and on the adsorption process of Pb(II) ions on the mixture of bentonite and botto...

The numerical simulation of a level IV fugacity model coupled to a dispersion-advection equation to simulate the environmental concentration of a pesticide in rice fields is presented. The model simulates the dynamic distribution of the pesticide in a compartmental system constituted by air, water, rice plants and bottom sediment together with saturated soil layers. The level IV fugacity model ...

Massive amounts of anthropogenic radiocaesium Cs that were released into the environment by the Fukushima Daiichi Nuclear Power Plant accident in March 2011 are widely known to have extensively migrated to Pacific Ocean sediment off of eastern Japan. Several recent reports have stated that the sedimentary Cs is now stable with a remarkably heterogeneous distribution. The present study elucidate...

Research on the propagation of acoustic waves in the ocean bottom sediment is of interest for active sonar applications such as target detection and remote sensing. The interaction of acoustic energy with the sea floor sublayers is usually modeled with techniques based on the full solution of the wave equation, which sometimes leads to mathematically intractable problems. An alternative way to ...

Deep-sea sediment pore fluids contain a record of past glaciations in their [Cl] and N18O. The signal of the Last Glacial Maximum (LGM) ice volume increase remains in the pore fluids as a local peak in each of these species. Using a one-dimensional model to account for the diffusive and advective transport within the sediment column since the LGM, the past bottom water salinity and NOseawater v...

Variation of the chemical composition of bottom sediments collected from three lakes with different water mixis, morphometric parameters, catchment areas and anthropogenic pressures was analyzed. Sediment samples were characterized by water content and concentrations of organic matter, nitrogen, phosphorus, calcium, iron and aluminium. Statistically significant correlations between the content ...