effects of irrigation with depurated livestock effluents on soils. a case study from central italy

The work deals with the qualitative modifications of a Calcaric fluvisol after irrigation with fresh water and depurated pig-slurry effluents (aerobic and anaerobic treatment, and phytodepuration with a reed bed system). The accumulation of nutrients (nitrogen and phosphorus) and heavy metals (Cd, Co, Cr, Cu, Ni, Pb, Zn) as total and as bio-available forms in the soil was evaluated, together with soil aggregate stability index, hydraulic conductivity of the saturated soil and the in situ infiltration rate. The experimental field was divided into three plots, and cultivated with silage maize for three years (2003-2005). Results showed that the irrigation with depurated and phytodepurated effluents produced significant changes in the soil chemical properties controlling soil permeability, and influenced the bio-available fraction of heavy metals.