|KOONTZ, MELISSA - University Of Memphis|
|KOONTZ, JOSHUA - Us Army Corp Of Engineers (USACE)|
|PEZESHKI, S - University Of Memphis|
Submitted to: Journal of Plant Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/17/2012
Publication Date: 10/25/2013
Publication URL: http://handle.nal.usda.gov/10113/58923
Citation: Koontz, M.B., Koontz, J., Pezeshki, S.R., Moore, M.T. 2013. Nutrient and growth responses of Leersia oryzoides, rice cutgrass, to varying degrees of soil saturation and water nitrogen concentration. Journal of Plant Nutrition. 36(14):2236-2258.
Interpretive Summary: The use of plants to clean up contaminants (phytoremediation) is growing in popularity among farmers and conservationists. Using vegetated drainage ditches is an economical and environmentally sound way to help alleviate contaminants associated with agricultural runoff. However, little research has examined the plant physiological responses, including nutrient uptake, when exposed to variable flooding regimes. Results from this study indicated that rice cutgrass, a common drainage ditch species, can affect nutrient and other elemental concentrations in runoff water through trapping and allocation of materials to plant leaves, stems, and roots. This information will be of benefit to farmers, conservationists and landowners committed to improving ecosystem health.
Technical Abstract: Leersia oryzoides (rice cutgrass) is an obligate wetland plant common to agricultural ditches. The objective of this greenhouse study was to quantify the allocation of nutrients and biomass to different plant components exposed to various soil moisture and aqueous N input regimes. Plants in the continuously flooded treatment had the highest tissue concentrations of Cu, S, Zn, K, Na, and Mn in one or more plant components. The partially flooded treatment had the highest concentrations of Mg in leaves and of Na in adventitious roots. The N input regimes significantly affected concentrations of P and S in adventitious roots. Leaf, stem, and adventitious root biomass were highest in partially flooded plants. Continuously flooded plants allocated the least resources to rhizome production. These results indicate that L. oryzoides may significantly affect elemental concentrations in surface waters by its ability to uptake various elements and subsequent sequestration in various biomass components.