Relations between heavy metal levels in soil, detritophagous and phytophagous invertebrates

Abstract

Heavy metal (HM) levels in soil samples taken from surface soil horizon (up to 30 cm depth) and in the bodies of two invertebrate groups (earthworms as detritophagous and snails as phytophagous) were investigated during the vegetation period of 1993 in Central Moravia. Within the frame of large scale monitoring the above samples were taken repeatedly in ten selected habitats, mostly Protected Landscape Areas (PLA) and forests, and heavy metal levels of seven elements (Cd, Pb, Cr, Mn, Cu, Zn, Fe) were estimated by AAS after laboratory treatment. In soil samples three HM forms (fixed, soluble and available) were differentiated. Results indicated that the individual HM are distributed in a characteristic way both in soil and in invertebrate bodies. A relative comparison indicated that soil is the main depot for Pb, Cr, Mn and Fe, whereas biomass accumulates mainly Zn, Cu and Cd (related to kg dry matter). Characteristic differences were also found in the HM levels between detritophagous (earthworms) and phytophagous (snails) invertebrates. Elevated HM levels in several Protected Landscape Areas should be considered as warning symptoms.