Assessment of earthworm activity on Cu, Cd, Pb and Zn bioavailability in contaminated soils using biota to soil accumulation factor and DTPA extraction.

Abstract The study aims to investigate effect of earthworm activity on metal bioavailability in soils using their BSAF-metals. Based on a microcosmic laboratory experiment, epigeic species Amynthas corticis (A. corticis) and endogeic species Amynthas robustus (A. robustus) were cultured in two types of soils contaminated by Cd, Zn, Pb and Cu for 120 days. Earthworm characteristics (i.e. numbers, biomass and BSAF), soil properties (i.e. pH, organic C and N contents along with their components such as mineralization and microbial masses) and DTPA extracted metals in soil were determined. After the incubation, the biomass and survival numbers of both earthworm species decreased significantly (P