The results showed that 'Australia' canna had the greatest water consumption, total biomass production, and aboveground nitrogen and phosphorous content, followed by pickerelweed. 'Golden Fleece' iris had higher tissue nitrogen concentrations than canna, but much lower biomass production. Dwarf papyrus had similar total biomass as pickerelweed, but less shoot biomass. Nitrogen and phosphorous removed from the NRS units planted with canna (98.7% N and 91.8% P) were higher than those planted with iris and arrow arum (31.6% and 31.5% N, and 38.5% and 26.3% P, respectively). NRS units planted with dwarf papyrus had similar nutrient recovery rate as pickerelweed, but much less total N and P were removed as a result of less water consumption. The NRS units planted with calla lily had lower nutrient removal than canna and pickerelweed.
Results from the study suggest that ornamental canna has the potential to be used as mitigation plants in urban stormwater floating biofiltration treatment. Because canna is a perennial plant and allocates the majority of its biomass to shoots, it can be harvested regularly, offering consistent removal of biomass from the treatment system. Chen noted that more research needs to be done to evaluate factors that might affect its application, such as "nitrogen and phosphorous loading and hydraulic conditions, planting densities, poly culture, harvesting frequency, and growth maintenance techniques."
|Contact: Michael W. Neff|
American Society for Horticultural Science