Irrigation of eucalyptus plantation using treated bleached kraft pulp mill effluent

Area of Science:

• Environmental Science
• Soil Science
• Forestry

Background:

• Pulp mill effluent offers potential for plant nutrition and water supply in eucalyptus plantations.
• Utilizing treated effluent serves as a supplementary treatment and disposal method for pulp mills.

Purpose of the Study:

• To evaluate the effects of bleached kraft pulp mill treated effluent on three Brazilian soils for eucalyptus cultivation.
• To determine optimal effluent application rates based on sodium load for eucalyptus plantations.

Main Methods:

• Characterization of treated pulp mill effluent.
• Controlled greenhouse experiments with five different effluent application rates based on sodium load.
• Six-month monitoring of soil properties and eucalyptus plant growth.

Main Results:

• Increased soil salinity was observed after effluent application, but no soil dispersion occurred.
• Fine-textured soil showed the best biomass productivity and plant growth at a sodium loading rate of 6.49 t Na ha(-1).
• Low nutrient content in the effluent necessitates fertilizer supplementation.

Conclusions:

• Treated pulp mill effluent is a feasible option for eucalyptus irrigation when managed properly.
• Adequate management practices and continuous monitoring are crucial for successful effluent application.
• The soil-plant system demonstrated a positive response, highlighting the potential of this practice.