Influence of nitrogen fertilizer on Cd and Zn accumulation in rapeseed (Brassica napus L.) biomass
¹Aleksandras Stulginskis University, Institute of Environment and Ecology,
Studentu str. 11, Akademija, LT-53361 Kaunas dist., Lithuania
²Lulea University of Technology, Department of Civil, Environmental and Natural
Resources Engineering, SE 971 87 Lulea, Sweden
Diffuse soil contamination with heavy metals and Cd in particular is a matter of serious concern. Application of conventional remediation methods usually is not feasible due to the large territories and relatively low heavy metal content. Thus, phytoremediation is seen as an alternative. Rapeseed was grown on Cd and Zn contaminated as well as clean soil under the greenhouse conditions. Solid and liquid nitrogen fertilizers were applied during the pot experiment in order to test their influence on heavy metal accumulation in plant tissues. Vegetative parameters were measured four times during the pot experiment and it was concluded, that the elevated concentrations of Cd and Zn in the soil did not disrupt the development of rapeseed plants. Furthermore, plants from contaminated soil produced significantly bigger seeds in comparison to plants from uncontaminated soil. Calculated Bioconcentration factors for rapeseed grown on Cd and Zn contaminated soil in all cases were below unity, thus possibility to use this plant species for phytoextraction purposes is limited, but it can be successfully grown on contaminated land as an energy crop. Application of nitrogen fertilizers had a significant effect on heavy metal accumulation and decreased Cd and Zn concentrations in rapeseed roots and stems with leaves were recorded. Accumulation differences between the liquid and solid fertilizer applications were negligible.