Purification of landscape water by using an innovative application of subsurface flow constructed wetland

• Published in: Environmental science and pollution research international 2016-01, Vol.23 (1), p.535-545
• Main Authors: Chyan, Jih Ming, Lu, Chien Chang, Shiu, Ruei Feng, Bellotindos, Luzvisminda M.
• Format: Article
• Language: English
• Subjects: Ammonium; Aquatic plants; Aquatic Pollution; Artificial wetlands; Atmospheric Protection/Air Quality Control/Air Pollution; Biochemical oxygen demand; Biodegradation, Environmental; Canna indica; Centella - metabolism; Chemical oxygen demand; Chlorophyll; Cyperus - metabolism; Cyperus alternifolius; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental Restoration and Remediation - methods; Environmental science; Eutrophic waters; Eutrophication; Evapotranspiration; Fish; Gardens & gardening; Hydrocotyle verticillata; Laboratories; Nitrogen; Nitrogen - metabolism; Nutrients; Performance evaluation; Pharmacy; Phosphorus; Phosphorus - metabolism; Pollutant removal; Pollutants; Ponds; Research Article; Studies; Suspended solids; Waste Water Technology; Water Management; Water Pollutants, Chemical - metabolism; Water pollution; Water Pollution Control; Water quality; Wetlands; Zingiberales - metabolism
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-015-5265-1

This study attempted to purify eutrophic landscape water under a low pollutant concentration and high hydraulic volume loading using an embedded subsurface flow (SSF) constructed wetland (CW). Three species of aquatic plants (i.e., Cyperus alternifolius subsp. flabelliformis , Canna indica , and Hydrocotyle verticillata ) were found to be conducive to the requirements of purifying the low-polluted water. Field results of nearly 2 years of experiments showed that SSF CW purified the eutrophic water and maintained the landscape water in a visibly clear condition. In an environment approaching the SSF CW background concentration, pollutant removal processes were divided into modulation and optimum performance periods. Average concentrations of biochemical oxygen demand (BOD), ammonium–nitrogen (NH 4 + –N), and total phosphorous (TP) in the optimum performance period were 0.69–1.00, 0.35–1.42, and 0.19–0.23 mg/L, respectively. Almost 500 days of BOD and NH 4 + –N removals were necessary to perform optimally. A shorter period, 350 days, was required for TP optimum removal. This feature of two stage removals was not found in chlorophyll-a (Chl-a) and suspended solids (SS), whose averages were 11.86–17.98 and 13.30 μg/L, respectively. Filter cleaning and water replacement were unnecessary, while only water recharging was needed to compensate for the water lost by evapotranspiration. The field SSF CW has maintained its performance level for over 7 years.