Comparison of the absorption and accumulation characteristics of five heavy metals among different industrial hemp varieties

This study examined variations in the enrichment and transfer of heavy metals by different industrial hemp varieties. Five main varieties(ym1~ym5) of industrial hemp were used as experimental materials to repair farmland seriously polluted by heavy metals in mining areas of Yunnan Province. Among the five industrial hemp varieties, ym1 absorbed the most Pb and Cd, ym3 absorbed the most As, Cu, and Zn, while ym5 had the lowest absorption of Pb, Cu, Cd, and Zn in mature roots. The maximum absorption of As, Cu, and Cd by stems and leaves was observed in ym3, and the maximum absorption of Pb and Zn occurred in ym1 and ym2, respectively. The maximum absorption of Pb and Cd by seeds was seen in ym2, of As and Cu was seen in ym5, and of Zn was seen in ym3. Seeds of ym1 showed the least absorption of Pb, As, and Cu, and the least absorption of Cd and Zn were seen in the seeds of ym4 and ym2, respectively. The enrichment coefficients of stems and leaves in the five varieties were greater than that of roots, except Cu. The transport coefficients of roots to stems and leaves were all greater than 1. In summary, ym1 can be used for Pb repair, and ym3 is suitable for As, Zn, Cu, and Cd repair.