A laboratory batch study on arsenic sorption and desorption on guava orchard soils of Baruipur, West Bengal, India

作者：Sahu Sudip Jyoti; Nath Bibhash; Roy Sharmi; Mandal Biswapati; Chatterjee Debashis^*

来源：Journal of Geochemical Exploration, 2011, 108(2): 157-162.

DOI：10.1016/j.gexplo.2011.01.003

• Arsenate sorption
• Bioavailability
• Langmuir isotherm
• Regression analysis
• Orchard soils

Groundwater contaminated with arsenic (As), when extensively used for irrigation, causes potentially long term detrimental effects to surface soils. Such contamination can also directly affect human health when irrigated crops, such as rice, vegetable and fruits, are used for human consumption. Therefore, an understanding of the sorption and desorption behavior of As in surface soils is of high importance, because these processes regulate the bioavailability of As in the soil environment. In this study, we have collected soils from guava orchards of Baruipur, West Bengal, and characterized soil chemistry and batch sorption and desorption behavior in the laboratory. The sorption and desorption behavior of As in the soils were examined using the Langmuir and Freundlich sorption equation. Regression analysis of the soil chemical characteristics and sorption equation parameters were also performed. The results suggest that the sorption behavior of arsenate is highly dependent on soil characteristics, specifically organic carbon, clay and Al(2)O(3) content of the soils. Whereas desorption behavior is critically influenced by the presence of high concentrations of amorphous and/or crystalline Fe(2)O(3) in the soils. Retention of the significant portion of As in the soils (similar to 84% of the total) suggests that As in the orchard soils may not be highly bioavailable to plants for uptake. However, more detailed studies will be required to ascertain the role of individual soil components on the As sorption and desorption processes.

• 出版日期2011-2