Copper Smelter Effluent Effects on Sonoran Desert Vegetation

The vegetation of an Arizonan upland community near a recently inactivated copper smelter at Superior, Arizona was studied. Vegetational parameters of species diversity, density, and cover were inversely related to concentrations of Cu, Cd, Pb, Fe, and Zn in the soil. Near the smelter, annuals, herbaceous perennials, grasses, cacti, and some shrubs were almost entirely absent. The most probable cause of the observed vegetational changes is effluents, particularly S02 and Cu, emitted by the copper smelter over its 47-yr history.