Use of tree seedlings for the phytoremediation of a municipal effluent used in dry areas of north-western India: Plant growth and nutrient uptake

Impacts of municipal effluent (ME) irrigation on soil physicochemical properties and its remediation by tree species were assessed with a view to utilize this resource in growing woodlot, controlling land degradation and improving environmental quality in suburban areas. Acacia nilotica L (babool), Dalbergra sissoo L (sissoo) and Eucalyptus camaldulensis seedlings planted in July 1998 were irrigated with ME at 1/2 PET (T-2), 1 PET (T-3). 2 PET (T-4), and with canal water at 1 PET (T-5). The control was soil without seedlings irrigated with ME at 1 PET (T-1). Application of ME increased minerals concentration from T-2 to T-4 in both soil and seedling in June 1999 and 2000 The increase in soil pH. EC, SOC was by <2.00-fold and availability of potassium (K), copper (Cu), iron (Fe). manganese (Mn) and zinc (Zn) by >2-fold. NH4-N by 10 44-fold and PO4-P by 6.57-fold in T-4 than those in T-5 treatment in 2000 Available NH4-N, PO4-P, Mg and K were higher in 0-15 cm soil layer but continued irrigation and low soil carbon influenced leaching of NO3-N. Na. Cu. Fe. Mn and Zn resulting their higher concentrations in 60-90 cm soil layer (P< 0 01) Lower soil nutrients in T-3 than in T-1 suggested soil amelioration by the planted seedlings and because of lowest concentration of most of the nutrients E camaldlensis showed highest soil amelioration capacity But nutrient utilization efficiency was highest in A. rulotica for K, Ca, Mg, Na. Fe, Cu and Zn. D. sissoo for N and P. and E. camaldulensis for Mn Thus, planting tree seedlings, particularly E camaldulensis, under ecological amelioration could in this way help in controlling land degradation and enhancing biomass and aesthetic benefits, although long-term application of effluent would lead to mineral/salt accumulation in soil and plants. (C) 2010 Elsevier B V. All rights reserved