抄録
Many of the elements in the soil circulate through the ecosystem : soil (source) →plant (assimilator) →animal (predator) →microorganism (decomposer) →soil. In this circulation of elements, plant occupies a special and important position that the elements in the lithosphere firstly enter into the biosphere. Since 1900, the information on the existence and roles of trace metals in the plant has been much accumulated. These knowledges enable us not only to increase the crop yield but also to cure the disorders of crop, cattle and human caused by deficiency and excess of trace metals in the soil. In this paper such topics of essential (Cu, Zn, Mo, Mn, Fe) and non-essential (Cd, Al, Ge, Cr, Co, Ni, ) trace metals are briefly presented.
