B P International

In this study, hydrodynamics and sediment concentration equations of partial differential in 3-dimensions were solved using finite difference methods, the Crank Nicolson procedure to predict both sediment concentration and velocity profile of Nun River. The computer software (EKU2.8) which is a modification of the Navier Stoke’s equations was employed for discretization of Nun River stretch of 2,000 m into 2,245 rectangular meshes and simulation of the river’s flow velocity distribution. The code was validated by using the field water current measurements obtained from a selected stretch of the river. Average predicted velocities of 0.85 m/s, 1.542 m/s and 0m/s compared favorably with 0.8m/s, 1.475 m/s and 0.09m/s obtained from field measurement for upstream, midstream and downstream boundaries. The predicted results have approximate correlation coefficients of 0.96 for velocity distribution using Pearson product-moment method. The model proved very useful in predicting the velocity...

Speciation helps in the identifications and quantification of the defined geochemical fractions, forms or phases  in  which  an  element  exists  in  the  environment.  Speciation  in  sediment  compartment  is  a significant step to understand the potential environmental risk, distribution, mobility and bioavailability of pollutants. The total heavy metal concentrations of some environmentally toxic metals in sediments of the Pennington River System, Bayelsa state, Nigeria was examined. The concentrations of heavy metals  in  each  fraction  were  determined  using  a  ANALYST  400  Perkin-Elmer  AAS.  The  mean concentrations  (mg/kg)  for  the  six  metals  in  dry  season  sediment  samples  were:  0.14±0.17(As), 0.39±0.55(Co), 2.43±5.06(Cu), 26.82±22.19(Fe), 0.69±1.10(Pb), and 1.22±1.19(...