We published first Cu isotope data in pine tree rings and surrounding polluted and unpolluted soils in the Zambian Copperbelt. In highly polluted soil profiles, there is greater Cu isotope fractionation and Cu isotope compositions in tree rings indicate that there was a non-root uptake of Cu uptake by the trees.
Mihaljevič M., Jarošíková A., Ettler V., Vaněk A., Penížek V., Kříbek B., Chrastný V., Sracek O., Trubač J., Svoboda M., Nyambe I. (2018): Copper isotopic record in soils and tree rings near a copper smelter, Copperbelt, Zambia. Science of the Total Environment 621, 9-17. (DOI)