Effects of sewage sludge modified by coal gasification slag and electron beam irradiation on the growth of Alhagi sparsifolia Shap. and transfer of heavy metals

Abstract

A greenhouse experiment was performed to investigate the feasibility of sewage sludge modified by coal gasification slag pretreatment and electron beam irradiation in soil application for cultivation of Alhagi sparsifolia Shap. The results showed that modified sewage sludge had an active effect on the growth of Alhagi sparsifolia Shap. The sandy soil and modified sludge at the volume ratio of 2:1 were optimal, and the growth potential of Alhagi sparsifolia Shap. was highest. In the sandy soil, the values of bioconcentration factor of most heavy metals were below 1.0 except for Zn and Cu. The average bioconcentration factor values of heavy metals in Alhagi sparsifolia Shap. decreased in a sequence of Zn>Cu>Ni> Mn>Co>Pb>Cr>Fe>V>Cd>Mo for all treatments. Alhagi sparsifolia Shap. could decrease the eco-toxicity and bioavailability of Ni, Fe, and Mo in all mixed soil, and Alhagi sparsifolia Shap. could reduce the eco-toxicity and bioavailability of all heavy metals discussed in this study (except for Mn) in the mixed soil of SS:MSS = 2:1.