Irrigation of eucalyptus plantation using treated bleached kraft pulp mill effluent

摘要

The use of treated pulp mill effluent on eucalyptus plantation appears to be an attractive optionnfor plant nutrition and water supply. It also constitutes a supplementary treatment processnand a final disposal option for the mill effluent. This study aimed at the investigation andnevaluation of the effects of bleached kraft pulp mill treated effluent on three typical Brazilian soilsnused for eucalyptus plantation. The effluent was characterized and five different application rates,ndefined according to the load of sodium, were tested in controlled environment experimentsn(greenhouse). After effluent application over a six month period an increase in the salinitynof the studied soils was observed, although no soil dispersion was detected. The low contentnof some nutrients in the treated effluent indicated the need for fertilizer complementation.nIn general, the best biomass productivity and plant growth results were obtained in finentextured soil at a loading rate of 6.49 tNa ha21n. The good response of the soil-plant systemnunder different effluent application rates showed the feasibility for the eucalyptus irrigationnif adequate management practices and monitoring are carried out.