Study on absorptional efficiency of plants in Mount Beigu wetland

The wetland has drawn great attention on its application of denitrification and phosphorus removal as an effective and low-cost technology in treating wastewater. In order to study the absorptional efficiency of plants in Mount Beigu Hill, taking Phragmites australis and Phalaris arundinacea Linn (the two dominant species) as the investigative subject, measured the biomass, the total nitrogen (TN) and the total phosphorus (TP) of the different parts and analyzed corresponding dynamic patterns from March to September. The results showed that, (1)for both of the plants,the above-ground biomass increased earlier and reduced later during the whole growth stages, and stem had the highest biomass in all; (2)for both of the plants, the content of TN /TP in leaf was higher than that in stem and fringe. Meanwhile, Phragmites australis reached the peak accumulation in August, which got 38.97 g·m-2 TN、18.22 g·m-2 TP. For Phalaris arundinacea Linn, the peak accumulation occurred in May, which got 23.19 g·m-2 TN、6.32 g·m-2 TP;(3) both of the absorptional curves of TN and TP are single-peak-value for Phragmites australis and Phalaris arundinacea Linn, and the plants got better absorption of TN compared to TP, furthermore, Phragmites australis got better absorptional efficiency of TN/TP than that of Phalaris arundinacea Linn;(4) reaping the plants at right time can move 1248.90 kg TN and 381.8 kg TP out of the wetland and make some economic benefit by taking them as pulp sources.