Sources of deep groundwater salinity in the southwestern zone of Bangladesh

Abstract

Twenty groundwater samples were collected from two different areas in Satkhira Sadar Upazila to identify the source of salinity in deep groundwater aquifer. Most of the analyzed groundwater is of Na-Cl-HCO 3 type water. The trends of anion and cation are Cl, respectively. Groundwater chemistry in the study area is mainly governed by rock dissolution and ion exchange. The dissolved minerals in groundwater mainly come from silicate weathering. The salinity of groundwater samples varies from *1 to *5%, and its source is possibly the paleo-brackish water which may be entrapped during past geologic periods.

Hydrogeochemical investigation of groundwater in shallow coastal aquifer of Khulna District, Bangladesh

“…The total hardness (TH) in ppm (Todd 1980;Ragunath 1987;Hem 1991) was determined by following equation:…”

“…The residual sodium carbonate (RSC) is computed taking the alkaline earths and weak acids as follows (Ragunath 1987;Rao et al 2012);…”

Analysis of Deep Groundwater in the Sambagawa Belt in Relation to Growth of Komatsuna (Brassica rapa var. perviridis)

“…Some recent studies have focused on "deep groundwater," because knowledge about this resource can facilitate the development of water supplies and geothermal energy, and planning for underground waste injection or nuclear waste repositories (Rahman et al, 2011;Alley et al, 2013). Deep groundwater is poorly defined, but there is growing interest in understanding the typical depths from which groundwater is withdrawn to meet various demands for this resource (Alley et al, 2013).…”

Phytotoxicity of Arsenate and Salinity on Early Seedling Growth of Rice (Oryza sativa L.): A Threat to Sustainable Rice Cultivation in South and South-East Asia

“…For example, high As-contamination in groundwater and soils has been found across the south-costal part of Bangladesh (Brammer and Ravenscroft 2009;Meharg and Rahman 2003). Groundwater and soils of the coastal areas of the country are also affected by salinity (Ponnamperuma and Bandyopadhya 1980;Rahman et al 2011). …”

“…To avoid As problems, peoples of As and salinity affected southcoastal part of Bangladesh are extensively using groundwater from deeper aquifers, which is increasing salinity in groundwater by seawater intrusion (Rahman et al 2011). This pattern of concurrent occurrences of As and salinity problems has also been found in some parts of other S and SE Asian countries like Myanmar, Vietnam, and West Bengal of India (Fendorf et al 2010;Ponnamperuma and Bandyopadhya 1980).…”