PW08 Aquatic Ecotoxicology II
Exhibit Hall
8:00 AM - Wednesday
(PW112) A screen for nitrogen and phosphorus accumulation by ornamental plant varieties.
Taylor, M1, Polomski, R2, Klaine, S1, Whitwell, T2, 1 Clemson Institute of Environmental Toxicology Clemson University, Pendleton, SC, USA2 Department of Horticulture Clemson University, Clemson, SC, USA
ABSTRACT- Commercial nurseries use large amounts of water and nutrients to produce container-grown plants. Excess runoff contaminated with N and P can impact the quality of downstream waters. Constructed wetlands have been found to be highly efficient at removing N, but P removal was highly variable, with removal occurring during periods of active plant growth. Ornamental plants that remediate nutrients, especially P, would be very useful in constructed wetlands and buffer strips for commercial nurseries and greenhouses, golf courses, and residential lawnscapes that drain to surface waters. We examined N and P uptake by 17 taxa (19 varieties) of woody and herbaceous ornamental plants exposed to five concentrations of Hoagland′s solution in a pea gravel medium. A randomized complete block design with 6 replications was used and each varietal experiment was replicated twice. Herbaceous and woody ornamentals were harvested after 8 and 13 weeks, respectively. The total amount of Hoagland′s used, wet and dry weight of root and shoot biomass, and N and P content of root and shoot biomass were recorded/analyzed. Of the woody ornamentals, Virginia sweetspire, Itea virginica, bayberry, Myrica cerifera ′Emperor′, and silky dogwood, Cornus amonium, consistently performed better with fertilizer rates at or below those found in nursery runoff. Several herbaceous ornamentals performed well at low levels of fertilizer, including stargrass, Dichromena colorata, miniature cattail, Typha minima, and Louisiana iris, Iris x ′Full Eclipse′.
Key words: nitrogen, phytoremediation, phosphorus, nutrient contaminants