Short-term changes of metal availability in soil II The influence of earthworm activity
Coimbra, Joao Carlos; Pinto, Iraja Damiani; Wurdig, Norma Luiza; Do Carmo, Dermeval Aparecido
Applied Soil Ecology 49(none): 0-186
This study aimed to evaluate short-term earthworm-induced changes in the availability of metals applied to soil directly (metal-spiked) or via an organic matrix (sludge-amended). A laboratory experiment was performed using destructive sampling of microcosms filled with agricultural soil. A concentration gradient of industrial sludge contaminated predominantly with Cr, Cu, Ni, and Zn, and a soil freshly spiked with the same metal concentrations were applied on top of the soil columns. Individuals of Dendrobaena veneta (mimicking a realistic density of 5 earthworms per m2) were introduced in half of the replicates of each treatment. Total and .1M CaCl2 extractable metal concentrations. Highlights: Short-term earthworm-induced changes in soil metal availability were evaluated. Metals were applied to soil directly or via an organic matrix. Earthworm activity did not affect metal availability in soil over 12 weeks. Ni and Cu concentrations in D. veneta were higher at the highest treatment levels. Earthworm Cr and Ni concentrations were influenced by the matrices tested.