Impact of landuse on groundwater quality of Bangladesh

Groundwater pollution is a major concern in water resources management across the world. The objective of this study is to characterize groundwater quality and identify the impact of landuse on groundwater quality of Bangladesh. Total of 113 groundwater samples, collected from shallow aquifers at different locations of Bangladesh were analysed to estimate eight standard groundwater quality indices namely, sodium absorption ratio (SAR), soluble sodium percentage (SSP), residual sodium bi-carbonate (RSBC), permeability index (PI), total hardness (TH), magnesium adsorption ratio (MAR), Kelly’s ratio (KR) and total dissolved solids (TDS). The results showed that the SAR in groundwater of Bangladesh varies between 1 and 818, SSP between 9 and 99%, RSBC between − 13 and 719 meq/L, PI between 21 and 112%, TH between 233 and 19400 meq/L, MAR between 5 and 74%, KR between 0.06 and 135 meq/L, and TDS in the range of 51–15200 mg/L. Significant differences in groundwater quality indices between agricultural and forest lands were observed. The study revealed that higher amount of total dissolved salt in groundwater was due to sea water intrusion into the coastal aquifer. Relation between agriculture and groundwater quality suggests that though the nitrate concentration in groundwater was less than permissible level, it might increase in future due to extensive use of nitrogen-based chemical fertilizers in agriculture.