C and N mineralization and microbial biomass in heavy-metal contaminated soil

• DOI: 10.1016/j.ejsobi.2005.10.002
• Publication Date: 2005-12-23T00:30:19Z
• Authors: M.S Vásquez-Murrieta; I. Migueles-Garduño; O. Franco-Hernández; B. Govaerts; L. Dendooven
• Keywords: 13. Climate action; 15. Life on land; 01 natural sciences; 6. Clean water; 0105 earth and related environmental sciences

Abstract Heavy metals such as arsenic (As), lead (Pb), copper (Cu) and zinc (Zn) can be found in large concentrations in mine spills in Mexico. Interest in contamination by these heavy metals has increased recently as they can change the functioning of soil ecosystems qualitatively and quantitatively. They disturb the activities of soil fauna and contaminate drinking water in large parts of the world, which severely affects human health. Little, however, is known how heavy metals might affect the biological functioning of a soil. Soil was sampled from eight locations along a gradient of heavy-metal contamination with distance from a mine in San Luis Potosi (Mexico) active since about 1800 AD. Microbial biomass was determined with the original chloroform fumigation incubation (CFI) as well as extraction (CFE) techniques and the substrate induced respiration (SIR) technique while C and N mineralization were measured. Total concentrations of As in the top 0–10 cm soil layer ranged from 8 to 22992 mg kg–1, from 31 to 1845 mg kg–1 for Pb, from 27 to 1620 mg kg–1 for Cu and from 81 to 4218 mg kg–1 for Zn. There was a significant negative correlation (P