SM Imamul Huq, AFM Manzurul Hoque, JC Joardar and JU Shoaib
Keywords: Arsenic, movement, soil profile and land type.
Abstract: Study on the seasonal movement of arsenic and its retention in the profiles of some selected soils (Aeric Endoaquept) within a catena in the Old Meghna Estuarine Floodplain-a geologic formation having arsenic contaminated aquifers-reveals that arsenic accumulates both in irrigated and in non-irrigated lands to different extent during the dry season. Land types (based on inundation depth during monsoon) and duration of seasonal flooding were found to have a bearing on the movement and accumulation of arsenic in the soil profile. At the same time, internal drainage condition of the soils and intensity of rainfall may also direct the fate of arsenic in soils. Noticeable accumulation of arsenic was evident in all soil horizons of highland and medium highland after irrigation. But in irrigated medium lowland, arsenic accumulated in surface horizons (Ap1g and Ap2g) and deeper C2 horizon (below 0.9 m) only. A remarkable variation in leaching and accumulation of arsenic in the horizons of different irrigated and non-irrigated land was observed after monsoon. Variation in the duration and depth of submergence of soil in the same land type either by irrigation or by natural water might play an important role in determining the movement and retention of arsenic in soils due to their influence on soil properties like the iron, clay and organic matter contents.
[View Complete Article]