Remediation of sewage and industrial effluent using bacterially assisted floating treatment wetlands vegetated with Typha domingensis

Abstract

This investigation reports the quantitative assessment of endophyte-assisted floating treatment wetlands (FTWs) for the remediation of sewage and industrial wastewater. Typha domingensis was used to vegetate FTWs that were subsequently inoculated with a consortium of pollutant-degrading and plant growth-promoting endophytic bacteria. T. domingensis, being an aquatic species, holds excellent potential to remediate polluted water. Nonetheless, investigation conducted on Madhuana drain carrying industrial and sewage water from Faisalabad City revealed the percentage reduction in chemical oxygen demand (COD) and biochemical oxygen demand (BOD) to be 87% and 87.5%, respectively, within 96 h on coupling the plant species with a consortium of bacterial endophytes. With the endophytes surviving in plant tissue, maximal reduction was obtained in not only the aforementioned pollution parameters but for other major environmental quality parameters including nutrients (N and P), ions (Na and K), Cl, and SO as well, which showed percentage reductions up to 90%, 39%, 77%, 91.8%, 40%, and 60%, respectively. This significant improvement in polluted wastewater quality treated with the proposed method render it safe to be discharged freely in larger water bodies as per the National Environmental Quality Standards (NEQS) of Pakistan or to be reused safely for irrigation purposes; thus, FTWs provide a sustainable and affordable approach for in situ remediation of sewage and industrial wastewater.

Floating Wetlands: A Sustainable Tool for Wastewater Treatment

“…The hanging roots of plants below mat provide a large area for biofilms development and wastewater treatment . This is the reason that FTWs even have been proved effective for treatment of polluted surface water, sewage, industrial, and agricultural wastewater . Retention ponds are efficient to remove coarse and particulate forms of contaminants but not capable of removing dissolved contaminants effectively .…”

“…[17] This is the reason that FTWs even have been proved effective for treatment of polluted surface water, sewage, industrial, and agricultural wastewater. [10,14,34,65,95,170] Retention ponds are efficient to remove coarse and particulate forms of contaminants but not capable of removing dissolved contaminants effectively. [171] Although constructed wetlands can efficiently remove soluble pollutants and associated fine particles, these wetlands need large area and are unable to tolerate extended duration of high water levels.…”

“…[8] In recent years, variants of NFWs are exploited to treat anthropogenic discharges such as municipal wastewater, agriculture runoff, industrial effluents, etc. [9][10][11][12][13] This includes constructed wetlands (CWs), floating treatment wetlands (FTWs), hydroponic root mats (HRMs), etc. ( Table 1).…”

Cyperus laevigatus L. Enhances Diesel Oil Remediation in Synergism with Bacterial Inoculation in Floating Treatment Wetlands

“…Higher numbers of bacterial populations were counted in the T3 treatment; it was due to the efficient plant bacterial partnership. As reported by the previous study that plant roots provide residency and nutrients for proliferation of bacterial community present in outer and inner part of the tissues of the plant [52]. It has also been reported that rhizo bacteria that are involved in plant growth are probably to be present in inner tissue of plant (endophyte bacteria) at particular phase of their lifecycle so microbes can effectively penetrate in exposed plant parts especially in root and process of colonization of bacteria occurs by a dynamic mechanism for pollutant removal [23,53].…”

Plant-bacteria synergism: An innovative approach for the remediation of crude oil-contaminated soils

“…This technique provides a means of in situ treatment of contaminated land with high efficiency using natural biological activity. In plant-microbe synergism, plants offer nutrients and habitat to their associated bacteria and in return, microbes enhance plant growth and detoxify environmental pollutants (Chaudhry et al, 2005;Compant et al, 2010;Glick, 2010;Sessitsch et al, 2013;Afzal et al, 2014a;Ijaz et al, 2015bIjaz et al, , 2016Ahmed et al, 2017).). In this review, the contamination of environment with crude oil, remediation of soil contaminated with crude oil, plantbacterial synergism in phytoremediation, and role of rhizoand endophytic bacteria for the maximum remediation of the soil, are discussed.…”