The rhizome of cultivated Rheum in Qunjia of Qinghai province, was picked broke into cortex, phloem, xylem and marrow, the content of Cu, Zn, Fe, Mn, Co, Ni elements of the every tissue was analyzed by atom absorb spectrum.

• 采集青海群加地区种植大黄根茎，分为皮层、韧皮部、木质部和髓部等四部分，采用原子吸收光谱法分别测试了其不同组织中铜、锌、铁、锰、钻、镍等元素含量。