Nutrient accumulation by phragmites australis and phalaris arundinacea growing in two constructed wetlands for wastewater treatment

Abstract

Phragmites australis and Phalaris arundinacea are two most commonly used plants in constructed wetlands for wastewater treatment in the Czech Republic. This chapter deals with development of biomass, nitrogen and phosphorus concentration in that biomass and nutrient standing stocks in Phragmites and Phalaris growing in two constructed wetlands. Phragmites aboveground biomass varies between 781 and 2532 g m-2 in Břehov and between 1309 and 2177 g m-2 in Mořina. Phalaris aboveground biomass varies between 1262 and 2265 g m-2 in Břehov and between 1194 and 1780 g m-2 in Mořina. These values are within the common range found in both natural and constructed wetlands for wastewater treatment. For both Phragmites and Phalaris the aboveground biomass was higher than belowground. Nitrogen and phosphorus concentrations in Phragmites aboveground biomass were comparable with concentrations found in both natural stands and constructed wetlands. On the other hand, N and P concentrations in Phalaris were lower than those found in constructed wetlands. Nitrogen standing stocks in Phragmites and Phalaris were comparable with those found in natural stands and constructed wetlands and for both species substantially more nitrogen was sequestered aboveground. When comparing Phragmites and Phalaris N standing stocks, Phragmites stocks were higher but only belowground standing stock was significantly higher. The Phragmites phosphorus standing stocks in our study are also comparable with standing stocks found in natural stands but they are also at the lower end of the range. © 2011 Springer Science+Business Media B.V.