The use of the freshwater snail Ampullaria tischbeini (Dohrn) as a biological control agent for remediation of salt-affected soil

Abstract

ABSTRACTThe aim of this study was to ascertain the utility of using the freshwater snail Ampullaria tischbeini as a biological control agent for the remediation of soil impacted with high levels of Na+. A. tischbeini has an important role in improving the physical and chemical properties of soils. Calcium (Ca2+) ions required to ameliorate sodic soil originate from the snail shells. As the snail shells decompose by natural chemical processes, they produce Ca2+ ions. The sodium adsorption ratio (SAR) in the plots with snails was dramatically decreased as compared to the control plot without snails. After two years, the mean SAR value at 0–10 cm soil depth was decreased by 23.5 in the plots with snails. The snail movements in sodic soils improved soil physical properties with an increase in infiltration rate and a decrease in bulk density. In 2012, the mean bulk density was 137 and 64 kg m–3 lower at 0–10 and 10–20 cm soil depths in the plots with snails, respectively, as compared to the control plot without snails. The experimental results demonstrate that A. tischbeini can be used as a biocontrol agent with potential utility for the remediation of sodic soils.