Nutrient distribution in three contrasting soils after anaerobic baffled reactor effluent application: A soil column study

The increasing need for wastewater reuse resulted in this study to investigate the effects of effluent from an anaerobic baffled reactor (ABR) on some chemical properties of three contrasting soils after effluent leaching and the implications for peri-urban agriculture. Soil columns were leached with ABR effluent or distilled water using 16 pore volumes after which the columns were sectioned into two cm layers. The 0-2 cm, 8-10 cm and 14-16 cm layers were analysed for inorganic-N, P and K. For all soils the nutrient content, especially P, of the 0-2 cm layer was significantly (p<0.05) higher than the middle and bottom sections of the columns. There were significant differences between the effluent and the water-leached soils in terms of P accumulation. The amount of inorganic-N and K in the top layer was not significantly different from the other layers with the exception of the 0-2 cm layer in the Sepane soil leached with effluent.