Bài viết Ảnh hưởng của than sinh học đến hàm lượng kim loại ở dạng trao đổi trong đất trồng lúa nước được thực hiện với mục tiêu đánh giá ảnh hưởng của than sinh học sản xuất từ vỏ trấu đến hàm lượng kim loại ở dạng trao đổi trong đất trồng lúa nước trên hai loại đất có hàm lượng cacbon hữu cơ (OC) khác nhau. | VNU Journal of Science Earth and Environmental Sciences Vol. 39 No. 2 2023 78-94 Original Article The Effects of Biochar on Exchangeable Metal Concentration in Paddy Soils Nguyen Thanh Binh Ha Tran Quang Nghiem Institute of Environmental Science Engineering and Management Industrial University of Ho Chi Minh City 12 Nguyen Van Bao Go Vap Ho Chi Minh City Vietnam Received 17 September 2022 Revised 27 March 2023 Accepted 18 May 2023 Abstract The presence of metals in soil may impact the environment as well as agricultural products. Biochar can alter some physical and chemical properties of the soil reducing the concentrations of exchangeable metals in the soil. The aim of this study was to examine the effects of biochar on the exchangeable metal concentration in two paddy soils that have different organic carbon OC contents. A pot experiment was conducted in a greenhouse using two soils with high and low OC content mixed with biochar at rates of 0 3 6 and 12 and planted with rice in two consecutive seasons. At the end of each season 30 soil samples 2 soil types x 5 biochar rates x 3 replicates were collected to determine the exchangeable concentration of Al Fe Mn Cd Ni Pb and Zn as well as pH. The metal quality index was calculated using principal component factor analysis. The results showed that biochar increased the pH value after the first rice crop but did not improve after the second rice season. Biochar reduced the exchangeable concentration of some metals including Al Fe Ni Cd Pb and Zn. Compared to the no-biochar treatment biochar application increased the soil metal quality index from to after the first crop and from to after the second rice crop depending on soil properties and used biochar rate. This effect could be related to the increased pH in biochar-added soil and biochar s adsorption capacity. In conclusion biochar has promising prospects for reducing exchangeable metal content in arable soils thus exhibiting the .
