Qualitative assessment of sediment from River Meghna, Bangladesh

Abstract

The present study was conducted to find the status of different soil quality variables of the Meghna River during the period from September, 2015 to March, 2016. The values of different soil quality parameters such as silt, sand, clay, bulk density, pH, EC and organic matter fluctuated between 13.33-58.33%, 29.25-88.42%, 4.92-17.42%, 1.43-1.71g/cm³, 6.86-8.06, 43-942.67µs/cm and 0.24-3.1% respectively. The heavy metals were analyzed by Atomic Absorption Spectrophotometer (AAS). The observed order of heavy metals mean concentration in sediments Fe> Pb >Cr > Co > Cd in mg/kg, respectively. Significant differences (p<0.05) was found in the values of soil organic matter of the Meghna river in terms of sites. But the value of silt, sand, clay, bulk density, pH and EC exhibited no significant variation with sites. The concentration of silt, sand, clay, bulk density, pH, EC and organic matter showed no significant variation with seasons (p>0.05). Very strong positive correlation between Cr vs EC (0.965), Cd vs EC (0.962), Cd vs Cr (0.959) and bulk density vs % sand (0.951) was observed at the significance level 0.01. Fe vs % sand (0.944), Cd vs Fe (0.824), Pb vs % O.M (0.823) and bulk density vs Fe (0.822) showed very strong positive correlations at 0.05 level of significance. The concentration of the soil parameters indicate that the river is being polluted and the statistical analysis proved that anthropogenic sources are the main contributor.

Bangladesh J. Sci. Ind. Res.53(2), 89-98, 2018