A factorial experiment (3 X 5) was conducted at the Experimental Farm of El-Kassasin Hort. Res. Station, Hort. Res. Inst., Agric Res. Center, Egypt during the two successive seasons of 2009/10 and 2010/11. The main purpose of this research was to evaluate the capability of three Eucalyptus species (E. citriodora, E. gomphocphala and E. camaldulensis) grown under sandy soil conditions for reduce or eliminate contamination of some heavy metals resulted from sewage sludge application. This capability was determined under five tested levels of sewage sludge (0, 10, 20, 30 or 40 %) as untraditional organic fertilizer mixed with the sandy soil prior to eucalyptus plantation.
Obtained results showed that, E. gomphocephala retained the highest values of Zn, Pb and Cd content. Also the same species recorded significant increases in uptake of different plant organs and total uptake per plant of the above mentioned elements comparing to the other tested species. While, the highest values of translocation factor of Zn, Pb and Cd from root to leaves or to stem were noticed in E. citriodora in most cases.
Generally, as the mixed sewage sludge level was increased from zero up to the highest level of 40 %, the content as well as uptake of plant organs and total plant uptake of Zn, Pb and Cd were gradually increased. Translocation factor of Zn, Pb and Cd showed unspecific results with sewage sludge treatments.
Interaction treatments between eucalyptus species and sewage sludge applications supported that, E. gomphocephala was more capable to absorb heavy metals; Zn, Pb and Cd from the growing medium comparing to the other two tested eucalyptus species (E. citriodora and E. camaldulensis). Since, under the same sewage sludge level E. gomphocephala had more contents and uptakes of heavy metals comparing the other species. So, planting E. gomphocephala in sandy soil fertilized with sewage sludge was more effective in reducing the residues of such heavy metals pollute in growing medium.