Enhancement of surface flow constructed wetlands performance at low temperature through seasonal plant collocation

Abstract

In the present study, a novel seasonal plant collocation system (SPCS), specifically the Potamogeton crispus and Phragmites australis series system, was investigated to enhance the performance of surface flow constructed wetlands (SFCWs) at low temperature. Results of a year-round experiment showed that SPCS conquered the adverse effect of low temperature and achieved sustainable nutrients removal. In addition, during winter, removal efficiencies of NH-N, TP, COD, and TN in SPCS were 18.1%, 17.6%, 10.1% and 5.2% higher than that in the control, respectively. P. crispus and P. australis complemented each other in terms of plant growth and plant uptake during the experiment period. Furthermore, it emerged that P. crispus could increase the quantity of ammonia oxidizing bacteria by 10.2%, due to its high oxygen enrichment ability. It is suggested that seasonal plant collocation has a promising future in SFCWs of areas being affected by climate change, e.g. northern China.

Purification of Micro-Polluted Lake Water by Biofortification of Vertical Subsurface Flow Constructed Wetlands in Low-Temperature Season

“…The results show that the removal effect of TN by planting Oenanthe javanica and adding microorganism agent was much better than that of the blank control group. TN removal rates were consistent with the reported results [16,29]. Nitrification and denitrification are the main processes of nitrogen removal.…”

“…All samples were analyzed for chemical oxygen demand (COD), total nitrogen (TN), ammonia-nitrogen (NH 3 -N), and total phosphorus (TP), according to the Standard Methods for testing water and wastewater (APHA, 2005). Water temperature and pH were measured with a portable analyzer (HQ30d53LEDTM, HACH, Loveland, CO, USA) in the field [29].…”

Secondary effluent purification by a large-scale multi-stage surface-flow constructed wetland: A case study in northern China

“…Furthermore, it is generally accepted that CWs can treat wastewater within an optimal load capacity range, and out of range or changes in hydraulic loading will affect the oxygen environment and the removal processes of organic pollutants in CWs (Rai et al, 2013;Saeed and Sun, 2012;Wu et al, 2015a). Therefore, some alternative preventive measures and enhancing strategies such as insulation measurements, decreasing hydraulic loading, psychrotrophic bacteria addition, and seasonal plant collocation should be considered to improve wastewater treatment efficiency of CWs at low temperature in the future full-scale application (Wu et al, 2015b;Zhang et al, 2017).…”

“…Nowadays, when facing the rising demand for clean water, the treatment capacity and effluent quality is still relatively low even though the majority of existing WWTPs including various centralized and decentralized systems have been developed in developing countries (Wu et al, 2016a,b). Moreover, the standard limits for effluent quality and surface water quality are becoming much stricter in order to satisfy the growing environmental legislation (He and Xue, 2010;Rai et al, 2013;Wu et al, 2016a;Zhang et al, 2017). Therefore, some eco-sustainable treatment technologies after sewage treatment would be an alternative and economical option for secondary effluent purification.…”

Role of different plants on nitrogen and phosphorus removal at low temperature in lab-scale constructed wetlands

“…Therefore, it is particular important to ensure the nutrient removal capacity of CWs for plants at low temperature in winter. Seasonal plant arrangement, like P. crispus and P. australi series system, enhanced the performance of surface flow wetlands at low temperature [13] . In addition to plant configuration, it was also a useful way to improve CWs removal efficiency of pollutants in cold winter by planting cold-resistant plants or strong pollutants removal ability plants in winter.…”