Dual-role of coconut shell biochar as a soil enhancer and catalyst support in bioremediation

Abstract

The application of soil amendments has been proposed to influence soil properties, thereby improving agricultural productivity. They are known to increase the organic matter content, water holding capacity, and soil porosity, which play a significant role in the growth and development of plants. In work, experiments were carried out to evaluate the impact of coconut shell biochar as a soil amendment and microbial cell support to remediate cadmium-contaminated soil. To investigate the roles of biochar size and concentration on soil water holding capacity, the laterite loam soil is mixed with the biochar having different particle sizes of less than 1 mm, 1–2 mm, and 2–5 mm and concentrations of 1%, 5%, and 10% (w/w). The effects of combining biochar with different concentrations of 1%, 5%, and 10% (w/w) of farmyard manure on plant growth of Solanum lycopersicum L, soil nutrient changes, and enzyme activity are also investigated. The biochar particle size of <1 mm and concentration of 10% showed the highest (41.5%) water holding capacity and 90.47% germination, and 464.25 seed vigour index for Solanum lycopersicum L. Further 21 days soil incubation experiments were conducted to explain the effect of the biochar, and P. stutzeri immobilized on biochar on cadmium adsorption and bioavailability in soil. Cadmium removal of about 73.84% was obtained from contaminated soil compared to the control. It is suggested that coconut shell biochar generation from coconut shells could be a sustainable crop residue management option to enhance the soil physico chemical properties and also to remediate soil. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023.