Effect of Ca-Treated Cypress Biochar in Heavy Metals (Pb, Zn, Cu) Accumulation in Giraffe Heads (Lamium Amplexicaule L.)

In this study, we evaluated the efficacy of Ca-treated cypress biochar in reducing the bioavailability of lead (Pb), zinc (Zn), and copper (Cu) in contaminated soil, and examined the impact of biochar treatments on the growth of giraffe head plants and their accumulation of heavy metals. Soil samples were collected from Shimabara City, known for agricultural activities, and cypress biochar was added at different levels (1, 1.5, and 2% w/w). Giraffe head plants were cultivated under controlled conditions, and after 35 days, the shoot and root tissues were analyzed for heavy metal concentrations using X-ray fluorescence (XRF) analysis. The results showed that the addition of Ca-treated cypress biochar significantly reduced the uptake of Cu and Zn by giraffe head plants, while Pb concentrations were below the limit of detection. Increasing biochar levels led to a decrease in heavy metal concentrations in both shoot and root. Additionally, the addition of biochar had positive effects on the growth parameters of giraffe head plants, including shoot length and shoot dry weight, with the highest values observed in biochar treatment.