Effect of zone placement in soil on trace metal uptake by plants

Abstract

Abstract Corn (Zea mays L. cv. Golden Cross N.C.) was grown in Yolo loam soil (fine‐silty, mixed, thermic Typic Xerorthents) in pots in a glasshouse with different trace metals in excess in different zones of the soil. In one experiment, five different trace metals were applied simultaneously: in ng/g 13 Li, 200 Zn, 100 Ni, 200 Cu, and 75 Co all as sulfates. In another experiment they were applied separately. Trace elements were applied variously to the top half of the soil, the bottom half of the soil, one half of the soil vertically, all of the soil or none of the soil. When the top half or the side half of the soil was free of the trace metals, plants grew as well as where no trace metals had been applied to the soil. When the top half of the soil had been supplied with trace metals, plants grew just a little better than when they were mixed with all the soil and an apparent reason was roots growing down the sides of the container to the clean soil below. The volume of clean soil available to the plant...