Project 7

Quantifying Cu, Cr, Zn and U stable isotope fractionation by microbial populations

Lead partner: University of Oxford, UK
Marie Curie fellow: Melissa Murphy, UK (ER, post-doctoral researcher)

Microbial populations can provide important controls on metals transport in the environment. Bacterial populations control and drive metal precipitation, limiting migration and bioavailability of these metals in the environment, and this can be used for bioremediation of contaminated soils and aquifers and for the treatment of metal-loaded wastewaters. Bacterial processes have been found to isotopically fractionate Cu and Zn, though considerable work remains to delineate the fingerprints of specific bacterial populations and functional microbiological pathways involved.

This project will determine the effects of selected functional groups of bacteria on the isotopic signatures of selected metals and assess the extent isotopic transformations reflect specific microbial processes. This may be affected by the degree bacterial populations are stressed, and so may provide powerful tools for monitoring the effectiveness of different bacterial populations to react with metals under different stress conditions.

The isotopic ratios generated under different culture incubation conditions will also be included. This will be done using microcosms, characterised cultures, model wastewaters, and natural microbial communities.