Mineralogy of soils from different agroecological regions of Bangladesh: Region 17- lower Meghna River Floodplain

Abstract

Bangladesh is consisting of 30 Agro-ecological Regions (AEZs) and different applied agricultural research has been conducted based on AEZ. An attempt has been taken to study the mineralogy of important soils from all AEZs of Bangladesh in order to provide basic information for applied research. As part of this attempt, the mineralogy of ten soils from five representative soil series (Silonia, Homna, Debidwar, Chandraganj and Chandina) of AEZ 17, Lower Meghna River Floodplain, was investigated. The soils of the AEZ were mostly medium textured, non-saline and very strongly acidic to slightly acidic in nature. The average content of <2 μ,m clay fraction was 14.2% and it varied from 8.7 to 19.1%. The 2-20 μm silt fraction lied between 27.5% and 57.6% with an average of 43.2%. The clay fraction was dominated by mica, chlorite and kaolinite in all the soils studied. Presence of two interstratified minerals namely, vermiculite-chlorite intergrade and mica-chlorite interstratified minerals were evident in some samples. The findings of the present study do not support the proposed mineralogical suite of mica-smectite for this AEZ.