DISTRIBUTION OF COPPER SMELTER EMISSIONS IN SOUTHEASTERN ARIZONA - USING HONEY MESQUITE AS A BIOINDICATOR

Honey mesquite (Prosopis juliflora), a representative species of the S onoran Desert ecosystem, was studied as a possible bioindicator for in dustrial smelter pollution. Samples from soils, leaves and bark were c ollected along distance and elevation gradients from the largest opera ting copper smelter in Arizona and analyzed for element concentrations of Zn, Cu, Fe, Ti, Mn, Al, Mg, Ca, Sm, Ce, U, Th, Yb, As, La, Hf, Sb, Sc, V, In, W, Ba, Br, K, Na, Cl and Au. Depending on the sample type - soil, leaf or bark - between 5 and 15 elements were identified as sm elter immissions. Two distinct covariate element groups formed in samp les from the study site could be related to the chemistry of different smelting processes. A common atmospheric transport pattern was found to exist for the smelter emittants Cu, Sb and As over long distances. The identification and specification of smelter immissions in honey me squite makes this tree a well-suited bioindicator for industrial smelt er pollution.