Abstract:
Soil contamination with heavy metals has become a global concern because of its adverse effects on the ecosystem health and food security. Soil amendments including biochar can reduce the bioavailability of heavy metals in the contaminated soils and reduce their risk of entering the food chain. A pot experiment was conducted to investigate the effects of Cannabis biochar on the soil parameters such as pH, electrical conductivity, soil moisture content, total organic carbon and organic matter as well as on the plant parameters such as the maize plant growth and metal uptake by the roots and shoots of maize plants in a soil spiked with 150 ppm of Pb and Cd. At the end of the experiment, soils amended with biochar had slightly higher values for pH, EC, soil moisture content, total organic carbon and organic matter with theincrement pattern being more accentuated at the high biochar dose. Similarly, the plants grown in the soils amended with biochar showed significantly higher fresh and dry biomass average as compared to the control. The Cd uptake by the roots and shoots of the maize plants grown in soils amended with 1% and 5% biochar rates showed significant decrease in the Cd uptake as compared to that of the control at the end of the experiment and the Pb uptake by roots and shoots of the maize plants grown in biochar amened soils also showed significant decrease as compared to that of the control. Both 1% and 5% biochar rates were almost equally effective in reducing the Pb uptake. Experiment resulted that 5% biochar rate was more effective in increasing the mean values of soil parameters such as pH, EC, soil moisture content, total organic carbon and organic matter.