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1 Photograph examples of floating, submerged and emergent macrophyte life forms. From left to right: Persicaria amphibia
Source publication
Freshwaters are affected by a diverse range of pollutants which increase the demand for effective remediation. Aquatic phytoremediation is a nature-based solution that has the potential to provide efficient, spatially adaptable and multi-targeted treatment of polluted waters using the ability of macrophytes to take-up, sequester and degrade polluta...
Contexts in source publication
Context 1
... phytoremediation specifically uses macrophytes (i.e. freshwater adapted angiosperms, pteridophytes and ferns) for removing and degrading pollutants within aquatic environments (Rai 2009). This definition does not include microalgae species. Macrophytes can be broadly classified into three primary growth forms: floating, submerged and emergent ( Fig. 7.1). Floating macrophytes occupy the water surface and include genera such as Lemna (duckweeds), Hydrocharis (frogbit) and Nymphaea (water lilies) which may be free-floating or rooted. Submerged macrophytes grow primarily below the water surface and may be anchored to the substrate, although Ceratophyllum (hornwort) is a widespread genus ...
Context 2
... the experimental polluted water used has included storm water, lake water, river water, sewage effluents, domestic wastewaters, refinery wastewater, acid mine drainage and livestock effluents ( Zhu et al. 2011;Li et al. 2012;Borne 2014;Abed et al. 2017;Kiiskila et al. 2017). Mesocosm-scale studies are the most prominent form of exploration into the effectiveness of FTW thus far (Chen et al. 2016a, b), although there have been a few examples of deployment at field scale, such as Zhao et al. (2012) who demonstrated that TN and TP concentrations could be reduced in a polluted Chinese river. Mesocosm studies with synthetically produced experimental water allow full control of all input parameters. ...
Citations
... Macrophyte-rich systems can support diverse communities of microorganisms and small aquatic organisms, contributing to the overall health and ecological balance of the treatment system [43]. ...
Water scarcity becomes a pressing
issue when proper conservation measures
are not employed. In recent times, there has
been a gradual increase in the quantity of
polluted water, commonly referred to as
wastewater. To address this challenge and
utilize wastewater for human needs,
modern eco-friendly technology called
phytoremediation has emerged.
Phytoremediation is a green approach that
involves selecting suitable terrestrial and
aquatic plant species to treat wastewater
and remove various contaminants.
Hydrophytes, also known as aquatic
macrophytes, have proven to be effective
phytoremediators in both research and
commercial applications. This article aims
to raise awareness about the importance of
phytoremediation in wastewater treatment.
... They are considered a crucial component of an aquatic environment because they supply oxygen, organic materials, food, and shelter to many living organisms (Oyedeji and Abowei Communicated by Saikat Gantait. . Aquatic plants can also be used as ornamental aquarium and medicinal plants (Aasim et al. 2019), phytoremediation (Fletcher et al. 2020), waste water treatment , and water ecosystem biomonitoring (Zurayk et al. 2001). The demand for aquatic plants is growing rapidly, necessitating the development of an alternate method of mass propagation (Karatas et al. 2015). ...
In this study, response surface methodology (RSM) was used to optimize in vitro regeneration of the Brazilian micro sword (Lilaeopsis brasiliensis) aquatic plant, followed by data prediction and validation using machine learning algorithms. The basal salt, sucrose and Benzyaminopurine (BAP) concentrations were derived from Box-Behnken design of RSM. The response surface regression analysis revealed that 1.0 g/L MS + 0.1 mg/L BAP + 25 g/L sucrose was optimized for maximum regeneration (100%), shoot counts (63.2), and fresh weight (1.382 g). The RSM-based predicted scores were fairly similar to the actual scores, which were 100% regeneration, 63.39 shoot counts, and 1.44 g fresh weight. Pareto charts analysis illustrated the significance of MS for regeneration and fresh weight but remained insignificant. Conversely, MS × BAP was found to be the most crucial factor for the shoot counts, with MS coming in second and having a major influence. The analysis of the normal plot ascertained the negative impact of elevated MS concentration on shoot counts and enhanced shoot counts from the combination of MS × BAP. Results were further optimized by constructing contour and surface plots. The response optimizer tool demonstrated that maximum shoot counts of 63.26 and 1.454 g fresh weight can be taken from the combination of 1.0 g/L MS + 0.114 mg/L BAP + 23.94 g/L. Using three distinct performance criterias, the results of machine learning models showed that the multilayer perceptron (MLP) model performed better than the random forest (RF) model. Our findings suggest that the results may be utilized to optimize various input variables using RSM and verified via ML models.
Key message
Optimization of in vitro whole plant regeneration of Brazilian sword wood using response surface methodology
Data analysis through ANOVA, response surface regression anlaysis and machine learning
Graphical presentation of data via Pareto charts, normal plots, contour plots and surface plots for optimization
Better performance of ANN-based MLP model compared to decision tree based RF model
Graphical abstract
... In favorable environments, it can create large, nearly monospecific stands. Both plant species are utilized in phytoremediation (Azaizeh et al., 2003(Azaizeh et al., , 2022 and have been reported to play crucial roles in removing micropollutants from water, particularly in CWs for wastewater treatment (Fletcher et al., 2020). ...
... One strategy to mitigate stressors and restore water bodies in a sustainable way is to use nature-based solutions (NbS; van Rees et al., 2023). Aquatic phytoremediation is an NbS that utilises the capacity of aquatic plants (macrophytes) to uptake, sequester and/or degrade water-borne pollutants (Quilliam et al., 2015;Fletcher et al., 2020;Wang et al., 2002). However, most studies on aquatic phytoremediation focus on selecting macrophytes that optimally target single pollutants (Fletcher et al., 2022); whilst this approach is important it ignores the potential for multiple-pollutant uptake by macrophytes, and the parallel benefits that could be achieved through the additional provision of, for example, biomass production, habitat provision and pollination services. ...
... The removal of Cr(VI) from polluted waters using free-floating macrophytes has received attention due to its fast growth and easy culture in natural and artificial ponds (Fletcher et al. 2020). In many free-floating macrophytes, absorption and accumulation of Cr(VI) takes place in submerged roots (Marbaniang & Chaturvedi 2014), but the translocation of the metal to aerial parts (shoot and leaves) also occurs (Prado et al. 2016). ...
We analysed the capacity of Salvinia minima plants collected from different seasons to accumulate Cr(VI) in presence or absence of mineral nutrients. Plants were collected in August and November and they were grown in both water and Hoagland solution with and without Cr(VI). August plants showed development of new fronds, a low content of soluble sugars, and an increase in biomass. In November plants, a lower number of new fronds, a higher content of soluble sugars, and a lower increase in biomass were observed. November plants accumulated more Cr than those from August and the growth media showed an increase in DO. These results would indicate that a greater accumulation of biomass (August plants) does not necessarily lead to a greater Cr accumulation. Salvinia plants did not show demand for mineral nutrients except for phosphate and magnesium. Changes in the ion composition of growing media during the assay show possible differences in mineral requirement between higher and lower plants. Our results showed that Cr(VI) accumulation in S. minima plants depends on the development stage and the mineral nutrients composition of the growth medium.
... ST02: the constructed wetlands are recommended for stormwater treatment, mainly the surface water flow wetlands (Fletcher et al. 2020), which is chosen for this study. This type of wetland contains a specific type of vegetation that slowly filters the water as it passes through, degrading and absorbing pollutants (Fletcher et al. 2020). ...
... ST02: the constructed wetlands are recommended for stormwater treatment, mainly the surface water flow wetlands (Fletcher et al. 2020), which is chosen for this study. This type of wetland contains a specific type of vegetation that slowly filters the water as it passes through, degrading and absorbing pollutants (Fletcher et al. 2020). Since constructed wetlands for runoff water treatment require a significant amount of space due to the need for a sedimentation basin and an outlet structure (Lopez et al. 2018), this study focuses on their application only in park zones in the study area. ...
The simulation of urban water metabolism (UWM) allows for the tracking of all water, energy, and material flows within urban water systems (UWSs) and the quantification of their performance, including emissions into the air, water, and soil. This study evaluates seven drainage strategies (DSs) within conventional and sustainable urban drainage systems (SUDSs) using UWM and multicriteria decision analysis (MCDA). The DSs were designed to assess their corresponding UWM performances, employing key performance indicators (KPIs) related to sewer system balance, energy consumption, greenhouse gas (GHG) emissions, acidification, eutrophication, contamination, and sludge production. The outcomes were ranked using the compromise programming MCDA model. The top three strategies were permeable pavements, green spaces, and infiltration trenches and sand filters. The framework used for the evaluation of DS can provide valuable insights for decision-makers, support the promotion of sustainable integrated UWS management and adaptation, and accommodate design variations in urban drainage. Sensitivity analysis on uncertain parameters and KPI selection also contributed to robust and sustainable urban drainage solutions.
... The application of invasive plants into another natural habitat is inappropriate and hazardous. Invasive plants should not be employed unless containment can be guaranteed (Newete and Byrne 2016;Fletcher et al. 2020) Pistia stratiotes (water lettuce) is a perennial, free-floating plant with thick, soft leaves. It floats on the surface of the water while its root system is completely submerged. ...
Chromium (Cr) occurs in several oxidation states from trivalent to hexavalent. However, hexavalent forms are more toxic and mainly produced by anthropogenic activities. A hydroponic experiment was conducted to analyse the comparative remediation of Cr by Marsilea minuta and Pistia stratiotes. Plants were exposed to four concentrations of Cr (0.5, 1.0, 1.5, and 2.0 mM) for 3 days. The highest accumulation of Cr was seen at the 1.5 mM concentration after 3 days in Marsilea (11.96 mg/g) and Pistia (18.78 mg/g). Dry weights decreased and malondialdehyde (MDA) levels increased in response to increasing Cr concentrations. Results indicate that both macrophytes are suitable candidates for Cr phytoremediation. Antioxidant-enzyme activity as a function of metal tolerance is imperative for a coherent understanding of plant physiology under metal stress.
Graphical Abstract
... Aquatic macrophytes, defined here as emergent, floating or submerged plant species with distinct roots and shoots, have a significant capacity to uptake substances from their growth medium, thus lowering the pollution concentration of a target water body (Dhote and Dixit 2009;Fletcher et al. 2020). Phytoremediation comprises physical, chemical and biological processes , and as outlined in Fig. 2, this approach utilises many mechanisms, including (1) accumulation (phytoextraction, rhizofiltration); (2) immobilization (phytostabilization); ...
... Rhizofiltration, Known as phytofiltration, occurs in the root zone where contaminants are adsorbed/absorbed onto/into submerged plant organs (Dushenkov et al. 1995;Ansari et al. 2020;Olguín and Sánchez-Galván 2012). Given the significant role roots play in rhizofiltration, a suitable plant Table 1 Common mechanisms involved in phytoremediation by aquatic plants Adopted from Dhir (2013), Rezania et al. (2016), Sricoth et al. (2018), Fletcher et al. (2020) and Saleem et al. (2020) The mechanism in aquatic plants for this is characterised by having a large rapid-growth root system (Mareddy 2017). The root environments or exudates create favourable biogeochemical conditions that can precipitated contaminants inside the aquatic plant's root in an insoluble form. ...
... Emergent mac-rophytes can supply oxygen to the root zone, thereby facilitating degradation processes in the rhizosphere. Hydrophobic compounds which do not typically translocate into the shoots can instead serve as a microbial carbon source and undergo degradation in the root zone (Fletcher et al. 2020). The degradation efficiency of plants has also been shown to be significantly improved using genetic engineering to develop transgenic plants capable of overexpressing bacterial enzymes, which can increase transformation efficiency (Cherian and Oliveira 2005). ...
Antimicrobials, heavy metals, and biocides are ubiquitous contaminants frequently detected in water bodies across the globe. These chemicals are known as drivers of antimicrobial resistance (AMR), as these chemicals can select for resistance. Tools and processes, are therefore, needed to remove these chemicals from the environment to tackle the environmental component of AMR. Aquatic phytoremediation is a nature-inspired green solution to remove contaminants from the environment. Phytoremediation utilises macrophytes’ ability to sequester and degrade chemical pollutants in aquatic environments. In this review, we define the problem statement by highlighting the presence of AMR drivers in the aquatic environment. We also provide an in-depth review of phytoremediation to tackle chemical pollution by evaluating mechanisms for the removal and degradation of chemicals. This review identifies potential hyper-accumulators and understands how plant species and chemical composition can influence the potential for accumulation. Different pollutants accumulate to different extents in a range of aquatic macrophytes. Therefore, the combined use of floating, submerged and emergent plants would facilitate the optimum removal of AMR drivers considered in this review. A suggested configuration includes Helianthus annus around the edge of a contaminated site, followed by a belt of submerged plants ( Myriophyllum aquaticum ) and a bed of floating plants (e.g., Lemna species) together with the hyperaccumulator, Phragmites australis . Whilst phytoremediation offers a promising option to treat contaminated water, several critical knowledge gaps still exist. The effect of co-exposure to contaminants on the accumulation potential of plants and the fate of antibiotic-resistant genes and bacteria during the phytoremediation process are highlighted in this review. Based on this understanding, targeted areas for future research are proposed.
... The surface water pollutants that are of concern and where remediation solutions are being developed. Water pollutants can be broadly categorized as either organic, e.g., hydrocarbons, pesticides, and algal toxins, or inorganic (metals or synthetic and manure-based fertilizers containing excess amounts of N and P, or biological [pathogens and algal toxins] [5]. The current biological treatment plants in the most developed countries are quite effective in removing the main pollutants from water. ...
... In surface waters, plants can be grown to remove pollutants from water and sediment [8,9] and can be deployed either at the point source or in water bodies where pollution is diffused [10]. Thus, the process of phytoremediation can be used both for sustainable sanitation and as a management strategy for nutrient recovery from water [5]. Emergent and floating macrophytes primarily absorb nutrients and other contaminants through their roots and stem tissue [11]. ...
Unlabelled:
This study focused on the potential for pentachlorophenol removal by a biological process in secondary treated wastewater (STWW). The proposed process is a combined method of phytoremediation using a native plant, Polypogon maritimus and Lemna minor, and bioaugmentation using a fungus. The bioaugmentation process was performed by a fungal isolate capable of removing PCP, isolated from the compost. The identification of the fungus was performed by morphological, biochemical, and molecular methods. A biological treatment system by bioaugmentation and phytoremediation was set up to estimate the capacity of this process to eliminate a high concentration of PCP. physico-chemical parameters, such as pH, COD, and BOD were tested at experimentation times T0 (initial) and Tf (final). The concentration of PCP is controlled by the HPLC method. Thus, the growth of the fungus was determined by spectrophotometry and enumeration on the agar medium. The results obtained show that the isolated and selected fungus is identified by Penicillium Ilerdanum. The fungal strain used has a significant capacity for tolerance and elimination of PCP. The results of the physico-chemical parameters showed an improvement in the quality of wastewater after the treatment was carried out. The elimination of PCP came with a release of Common law- and an important decrease in the DOC value in the STWW. The results obtained show that the Polypogon treatment shows a significant elimination of PCP by a percentage of the order of 92.01% and 23.58 g. L- 1 chloride concentration. The macrophytes used showed a better ability to tolerate and eliminate PCP with an increase of chlorophyll and its longer sheets.
Supplementary information:
The online version contains supplementary material available at 10.1007/s40201-023-00865-y.
... Phytoremediation is an NbS that has gained attention to its comparable or greater efficiency and lower cost compared to physicochemical technologies for removing antimicrobials from water [10,12,[28][29][30][31]. This technique involves using plants to stabilize, accumulate, degrade, and/or transform contaminants into their biomass, with or without the involvement of associated microorganisms [29,[31][32][33]. ...
... Phytoremediation is an NbS that has gained attention to its comparable or greater efficiency and lower cost compared to physicochemical technologies for removing antimicrobials from water [10,12,[28][29][30][31]. This technique involves using plants to stabilize, accumulate, degrade, and/or transform contaminants into their biomass, with or without the involvement of associated microorganisms [29,[31][32][33]. Aquatic macrophytes have demonstrated high efficiency in removing Cipro from water and their use in phytoremediation is gaining increasing attention. ...
Citation: Kitamura, R.S.A.; Fusaro, T.; Marques, R.Z.; Brito, J.C.M.; Juneau, P.; Gomes, M.P. The Use of Aquatic Macrophytes as a Nature-Based Solution to Prevent Ciprofloxacin Deleterious Effects on Microalgae. Water 2023, 15, 2143. https:// Abstract: Macrophytes have demonstrated excellent potential for the removal of pharmaceuticals from water. However, there is a lack of studies on the ecotoxicity of water after phytoremediation. In this study, we evaluated the toxicity of ciprofloxacin (Cipro) on the microalgae cells of Desmodesmus subspicatus exposed to water contaminated with Cipro and previously treated by Salvinia molesta or Egeria densa for 96 h. Microalgae exposed to Cipro (1, 10, and 100 µg L −1) in untreated water showed decreased rates of growth, respiration, and photosynthesis, and increased oxidative status (hydrogen peroxide concentration) and oxidative damages (lipid peroxidation). S. molesta exhibited a greater phytoremediation capacity than E. densa, reducing Cipro concentrations in water to below its toxic threshold to D. subspicatus (2.44 µg L −1), even when the antimicrobial was present at a concentration of 10 µg L −1. During the water treatment, neither S. molesta nor E. densa released compounds that had a toxic effect on D. subspicatus. This work demonstrates the novelty of using S. molesta and E. densa as a nature-based solution to remove Cipro from contaminated water. For the first time, we provide evidence of the ecotoxicological safety of this approach, as it prevents the deleterious effects of Cipro on photosynthetic microorganisms and helps to avoid the development of antimicrobial resistance.
