Effects of pulpmill effluent irrigation on the distribution of elements inthe profile of an arid region soil

A comparison was made between the distribution of nitrogen, phosphorous, so dium, calcium, magnesium, cadmium, electrical conductivity and pH in the to p 2.5 m of soil in two adjacent fields in Northern Arizona. One field had b een irrigated with pulpmill effluent for 15 years. The adjacent field had n ever been irrigated. Saltbush plants, Atriplex canescens (Pursh) Nutt. grow ing in the two fields were compared for differences in sodium, magnesium, c alcium, nitrogen and phosphorus content. Overall concentrations of all meas ured elements except calcium and cadmium were significantly elevated in the soil that was irrigated with effluent. Sodium concentration and pH were el evated in the upper soil horizon, whereas phosphorus concentrations were el evated uniformly. Differences in electrical conductivity and magnesium conc entrations between the effluent-irrigated field and the unirrigated field i ncreased with depth. Saltbush plants sampled from the irrigated field had h igher concentrations of phosphorus and sodium, and lower calcium concentrat ions than plants sampled from the unirrigated field. This soil could be a g ood repository for sodium, however, the nutrient content of the resident sa ltbush population was affected. Other tested elements appeared to leach rea dily. (C) 1999 Elsevier Science Ltd. All rights reserved.