Toxicity Abatement of Wastewaters from Tourism Units by Constructed Wetlands

Abstract

The present research intended to investigate the toxicity abatement of domestic wastewater after passing a biosystem composed of a constructed wetland (CW) followed by a pond. The wastewater was generated in a tourism house in a rural and mountainous context and passed through a septic tank before being diverted to a CW followed by a pond. A battery of ecotoxicological tests, comprising microalgae (Raphidocelis subcapitata), macrophytes (Lemna minor), cladocerans (Daphnia magna), and bacteria (Aliivibrio fischeri), was used to assess the toxicity of the wastewater collected before and after the CW and the water of the pond. Physicochemical parameters (pH, conductivity, chemical oxygen demand, biochemical oxygen demand, total suspended solids, phosphates, ammonium, and nitrate) were also determined. The CW was able to remove carbon and nutrients from the water with a concomitant reduction of its toxicity. This study, reinforced the added value of using toxicity tests as a complement to CW operational monitoring to validate the solution and to analyze possible readjustments that may be required to improve efficiency. This study lends further support to the claim that CWs can be a sustainable solution for treating small volumes of domestic wastewater in a rural context.

Role of Microorganisms in the Remediation of Wastewater in Floating Treatment Wetlands: A Review

“…The associated environmental and economic benefits have established CWs as a viable option for wastewater treatment [2]. These have been widely applied in the treatment of various types of wastewater, such as municipal, agricultural runoff, storm runoff, and industrial [3][4][5][6][7][8]. Floating treatment wetland (FTW) is a novel technology, based on a floating vegetated system, that has unique abilities to remediate wastewater [9,10].…”

Constructed wetland as a green remediation technology for the treatment of wastewater from underground coal gasification process

“…However, several authors have emphasized the importance of including bioassays to monitor the effect of wetland remediation technologies and they introduced different toxicity tests to their research [ 42 – 47 ]. The Microtox test was found to be one of the most sensitive and to have a better ability to evaluate the toxicity of treated and nontreated wastewater samples [ 44 ]. In our study, the Microtox test has proven to be a useful complement to chemical analysis in terms of evaluating the course of wetland remediation technologies.…”

Occurrence of Fecal Bacteria and Zoonotic Pathogens in Different Water Bodies: Supporting Water Quality Management

“…Briefly, two artificial ponds were located in a city garden (P1, Figure 1a) and a city park (P2, Figure 1b), respectively; one small pond was located on a roof terrace in the city, at the level of the seventh floor (P3, Figure 1c); an artificial pond was set up as a biological swimming pool, i.e., a swimming pool where the traditional chemical disinfection is replaced by natural biological processes for water purification, located in a private house in a rural area, serving three persons (P4, Figure 1d); a natural pond located in a rural protected area (P5, Figure 1e); and, an artificial pond (P6, Figure 1f), receiving treated wastewater by a constructed wetland in a tourism house (details described in [30]). Briefly, two artificial ponds were located in a city garden (P1, Figure 1a) and a city park (P2, Figure 1b), respectively; one small pond was located on a roof terrace in the city, at the level of the seventh floor (P3, Figure 1c); an artificial pond was set up as a biological swimming pool, i.e., a swimming pool where the traditional chemical disinfection is replaced by natural biological processes for water purification, located in a private house in a rural area, serving three persons (P4, Figure 1d); a natural pond located in a rural protected area (P5, Figure 1e); and, an artificial pond (P6, Figure 1f), receiving treated wastewater by a constructed wetland in a tourism house (details described in [30]). Samples were collected from each site in two different time periods of the same year (September and October) in sterilized glass bottles of 1 L, directly dispatched to the laboratory and immediately analyzed for physicochemical and microbiological analysis (Sections 2.2 and 2.3).…”