Department of Agricultural Chemistry & Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur-741 252, Nadia. West Bengal, India E-mail : sarojsanyal@ hotmail.com; sarojsanyal @yahoo.co.in Manuscript received 14 July 2004, accepted 30 August 2004 A laboratory transport study of aqueous arsenic under constant pressure head in four surface soils, collected from the paddy fields at four different arsenic-affected sites of the Deganga block of North 24-Parganas district of West Bengal, was

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... ducted with the help of double-chambered vertical column made of Borosil glass. The experimental data led to the Darcy's saturated hydraulic conductivity of the soils and accumulation or relative hold-up of arsenic in these soils as reveled by the corresponding breakthrough curves. The sigmoid shape of these breakthrough curves for the given passage of aqueous arsenic solutions through the present soils, thereby suggesting hydrodynamic dispersion, was noted, with a concomitant shift of the curves to the left of the corresponding inflextion points (at Pv = 1.10). Based on this, substantial arsenic retention by the given soils was inferred. In this regard, the arsenic retention through its interactions with the soil organic matter and the day fractions was also emphasized. Moreover, an attempt has been made in the present study to relate the arsenic retention by the given soils to the corresponding relevant physico-chemical properties. The findings from the laboratory experiment were found to be satisfactorily correlated with the arsenic build-up in the different parts of summer (boro) paddy cultivated in the given affected soils. The latter may he taken to elucidate the effect of such irrigation on crops grown in the arsenic contaminated soils using the contaminated groundwater as the irrigation source.