Purification effects of Sonneratia apetala simulated wetland system on wastewater
LI Mei1, LIAO Bao-wen1, LIU Jin-ling2, ZHANG Jia-en2, ZHOU Guang-yi1, SU Juan3
1. Research Institute of Tropical Forestry, CAF, Guangzhou 510520, China; 2. South China Agricultural University, Guangzhou 510520, China; 3. Forestry Administration of Guangzhou, Guangzhou 510030, China
A simulated mangrove Sonneratia apetala wetland was set up in a greenhouse.Through wastewater irrigating test,the purifying effects of simulated wetland system were studied.The synthetic wastewater SW had the characteristics and strength similar to normal domestic wastewater,while FW and TW had the nutrients and heavy metals as five and ten times as those in SW,respectively.Wastewater was irrigated quantitatively and regularly for 4 months.The average purifying rates of Sonneratia apetala simulated wetland system on the nutrients and heavy metals in synthetic wastewater were: N 84.6%,P 91.2%,Cd 91.2%,Pb 94.8%,Zn 84.9% and Cu 87.1%,in which the purifying rates of soil subsystem were: N 54.5%,P 76.5%,Cd 99.3%,Ni 99.2%,Pb 99.6%,Zn 99.3% and Cu 99.2%.These indicated that the soil subsystem played an important role on purification and that plants could avoid the damage of pollutants.But the purifying efficiency of soil subsystem on nutrients where plant had been grown was lower than that without plant growth because of the adsorption of N and P by S.apetala.
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