| dc.description.abstract | The causes of anthropogenic eutrophication in water bodies are multi-faceted and multigenerational, presenting an ever increasing need for effective and sustainable solutions.Phytoremediation presents a cost-effective strategy to improve water body nutrient retention and removal, contributing to eutrophication mitigation efforts.
This thesis examines the potential for northern wild rice (Zizania palustris L.) to be used
as a phytoremediation species in eutrophic wetlands. An investigation into root-sediment
interactions was undertaken to determine how northern wild rice affects water and
sediment pore water chemistry. Northern wild rice growth was found to alter sediment
pore water chemistry, contributing directly to nutrient retention during the summer
growing season through nutrient assimilation in its tissues, and indirectly through
increasing pore water Fe and Mn in the fall. The majority of P and N within the plant
was found to be contained in the stems and leaves (44-53%), followed by the
inflorescence (22-28%). Harvesting northern wild rice vegetation (including the seeds) at
the end of the growing season would present a permanent nutrient removal mechanism.
Substantial iron plaque forms on the roots of northern wild rice, visible as an orangebrown
coating that ranges structurally from <1 μm to 14 μm thick. Iron plaques were
found to be composed mainly of Fe, O, Al and K, with Fe found within and on root
epidermal cells. P was not found to be associated with iron root plaques.
With proper harvesting and management techniques, northern wild rice grown in
eutrophic water bodies could present a viable phytoremediation method for nutrient
removal. | en_US |
