Pollen provisioning attenuates pesticide side-effects on a phytoseiid predator

BACKGROUND

Biological control with predatory mites is applied against pests in greenhouse crops. Chemical control with the use of selective, reduced-risk pesticides, is an important component of Integrated Pest Management (IPM) programs, that often needs to be combined with biological control. Here, we evaluated the effect of plant pollen when used as supplementary food on the survival, reproduction and predation of the predatory mite Amblydromalus limonicus (Acari: Phytoseiidae) after exposing young larvae and adults to flonicamid, an insecticide of moderate toxicity to phytoseiids. Pollen is an important alternative food for generalist phytoseiids ensuring survival and supporting populations build-up during periods of prey scarcity. Two regimes of cattail (Typha angustifolia L.) pollen differing in application frequency were used. In the first, the total amount of pollen was supplied once, within 30 min after insecticide application, whereas in the second regime, the same amount of pollen was supplied gradually, i.e., every 48 h.

RESULTS

Regardless of the frequency of application, pollen provisioning results in a reduction in prey (thrips) consumption relative to the control (no pollen provisioning). Nevertheless, when adult mites were directly exposed to flonicamid residues, pollen provisioning attenuated the reduction in prey consumption as compared to the control. In addition, the gradual (every 48 h) provisioning of pollen to adult predators exposed to flonicamid residues impacted positively the intrinsic rate of population increase (rm) of A. limonicus as compared to when feeding on prey.

CONCLUSION

Our results reveal an unexpected role of pollen provisioning in alleviating pesticides side-effects on phytoseiids. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Resistance of the fiber-derived geotextile from Typha domingensis submitted to field degradation

Geotextiles made from plant fibers creates a suitable environment for plant growth as part of soil bioengineering techniques. The faster decomposition of plant fiber geotextiles compared to synthetic ones demands the use of composites that enhance their waterproofing and extend their durability in the environment. The objective of this work was to evaluate the resistance of a geotextile made with Thypha domingensis to degradation caused by climatic variables. Tensile strength tests were conducted in the laboratory in order to evaluate the degradation of geotextiles treated with single and double layers of waterproofing resin. Based on Scanning Electron Microscopy (SEM) images, it was verified that applying double layer of waterproofing resin delays the fibers degradation up to 120 days of exposure to the effects of climatic variables other than temperature. The maximum resistance losses due to the geotextile's exposure to degradation were statistically significant for all three treatments: control-without waterproofing resin, with one layer resin, and with two layers resin. Therefore, waterproofing resin, provides a long-term protective solution for geotextiles made from cattail fibers.

Optimizing Typha biochar with phosphoric acid modification and ferric chloride impregnation for hexavalent chromium remediation in water and soil

Considering the persistent and covert nature of heavy metal soil contamination, the sustainable development of ecological environments and food safety is at significant risk. Our study focuses on remediating soils contaminated with chromium (Cr); we introduce an advanced remediation material, iron oxide phosphoric acid-loaded activated biochar (HFBC), synthesized through pyrolysis. This HFBC displays greater microporosity, fewer impurities, and enhanced efficiency for the remediation process. Our research utilized a comprehensive set of analytical techniques, including Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS), alongside adsorption studies to elucidate the Cr removal mechanism. The effectiveness of HFBC in remediation was influenced by several factors: the pH level, dosage of HFBC, the initial concentration of Cr, and the ambient temperature. Our results indicated an optimal chromium (VI) adsorption capacity of 55.5 mg/g by HFBC at a pH of 6.0 and a temperature of 25 °C, with the process adhering to the pseudo-second-order kinetic model and the Langmuir adsorption isotherm, thus suggesting spontaneity in the uptake method. Moreover, this mechanism encompasses both adsorption and reduction reactions. Using HFBC in pot experiments with cabbage indicated not only an increase in soil pH and cation exchange capacity (CEC), but also a surge in bacterial community abundance. Significant reductions in bioavailable chromium were also recorded. Interestingly, HFBC addition bolstered the growth of cabbage, while concurrently diminishing chromium accumulation within the plant, particularly notable as the HFBC application rate increased. In summation, the HFBC produced in our study has demonstrated convincing efficacy in removing chromium from aqueous solutions and soil. Moreover, the positive agronomic implications of its use, such as enhanced plant growth and reduced heavy metal uptake by plants, indicate its high potential for operational value in the domain of environmental remediation of heavy metals.

Extraction and characterization of nanocellulose from cattail leaves: Morphological, microstructural and thermal properties

Hydrogen peroxide combined with acid treatment demonstrates its respective characteristics for the separation of lignocellulosic biomass. Herein, holocellulose was extracted from Cattail leaves (CL) by a two-step treatment with alkali and hydrogen peroxide-acetic acid (HPAA). Then carboxylated nanocellulose was hydrolyzed with a mixed organic/inorganic acid. The chemical composition of the holocellulose and the physicochemical properties of the separated carboxylated nanocellulose were comparable. Carboxyl groups were introduced on the nanocellulose as a result of the esterification process with citric acid (CA), which endows the nanocellulose with high thermal stability (315-318 °C) and good light transmission (>80 %). Furthermore, morphological analyses revealed that nanocellulose had a spider-web-like structure with diameter between 5 and 20 nm.

Seasonal variations of some heavy metals in common reed (Phragmites australis (Cav.) Trin. Ex. Steudel) and narrow-leaved cattail (Typha angustifolia L.) in Eğirdir Lake (Turkey) and the possibility of using for phytoremediation of these macrophytes

This study which was carried out between July 2019 and April 2020 aimed to determine the seasonal changes of heavy metals (Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se, and Zn) in plant organs of Phragmites australis and Typha angustifolia grown in Eğirdir Lake and to research the usability of the these plants for phytoremediation with the calculation of bioaccumulation factor (BF). Plant samples were brought to the laboratory, and then washed, cleaned with distilled water, dried in an oven at 70 °C and acidified with 10 ml HNO3. The samples were heated at 120 °C on a hot plate until completely mineralized. After mineralization, heavy metal concentrations were determined by using ICP-AES (Vista model). Only Mo was the highest in leaf, while other metals were highest in root in P. australis. In T. angustifolia, Mn and Mo were highest in the leaf, the accumulation of other metals was observed to be higher in the plant's roots than the other organs. It was discovered that the metal concentrations in root, in stem, and in leaf for both macrophytes generally increased in summer and decreased in root in autumn and winter and in stem and in leaf in spring for P. australis and in all organs in spring for T. angustifolia. Bioaccumulation factor (BF) values were calculated to determine the phytoremediation potential of P. australis and T. angustifolia. Both macrophytes are not excluder for all metals. Plants revealed potential for phytoremediation for the removal of heavy metals especially Mo and Zn. As a result of our study, it was determined that both macrophytes had accumulation abilities especially for Mo and Zn. It should be taken into consideration that these macrophytes can be used for improving the current situation of Eğirdir Lake due to their advantages such as being economical and not causing any harm to the environment.

Hydrothermal carbonization of Typha australis: Influence of stirring rate

According to existing literature, there are no conclusive results on the impact of stirring on hydrothermal carbonization (HTC); some studies report a significant impact on the product's properties, while others indicate no influence. This study investigates the influence of stirring rate on several responses and properties of HTC products, including solid mass yield, solid carbon fraction, surface area, surface functional groups, morphology, and the fate of inorganic elements during HTC. Waste biomass was introduced as a feedstock to a 2 L HTC reactor, where the effects of temperature (180-250 °C), residence time (4-12 h), biomass to water (B/W) ratio (1-10%), and stirring rate (0-130 rpm) were investigated. The findings of this study conclusively indicated that the stirring rate does not influence any of the studied responses or properties of hydrochar under the selected experimental conditions used in this study. Nevertheless, the results indicated that a low-stirring rate (5 RPM) is enough to slightly enhanced the heating-up phase of the HTC reactor. For future research, it is recommended to examine the impact of stirring rate on the HTC of other types of biomass using the methodology developed in this study.

Subsurface flow constructed wetlands for treating of simulated cadmium ions-wastewater with presence of Canna indica and Typha domingensis

The presence of toxic cadmium ions in the wastewater resulted from industrial sector forms the critical issue for public health and ecosystem. This study determines the ability of four vertical subsurface flow constructed wetlands units in the treatment of simulated wastewater laden with cadmium ions. This was achieved through using sewage sludge byproduct as alternative for the traditional sand to be substrate for aforementioned units in order to satisfy the sustainable concepts; however, Canna indica and Typha domingensis can apply to enhance the cadmium removal. The performance of constructed wetlands has been evaluated through monitoring of the pH, dissolved oxygen (DO), temperature, and concentrations of cadmium (Cd) in the effluents for retention time (0.5-120 h) and metal concentration (5-40 mg/L). The results demonstrated that the Cd removal percentage was exceeded 82% beyond 5 days and for concentration of 5 mg/L; however, this percentage was decreased with smaller retention time and higher metal concentration. The Grau second-order kinetic model accurately simulated the measurements of effluent Cd concentrations as a function of retention times. The FT-IR analysis indicated the existence of certain functional groups capable of enhancing the Cd removal. The treated wastewater's pH, DO, temperature, total dissolved solids (TDS), and electrical conductivity (EC) all meet the requirements for irrigation water.

Influence of water-level variability on fish assemblage and natural reproduction following connectivity enhancement in a Typha-dominated coastal wetland, USA

We evaluated a wetland habitat modification strategy to contrast fish assemblage structure and the production of young-of-the-year (YOY) fish between different engineered habitats (i.e., spawning pool complexes and connectivity channels) relative to unmodified lateral channels in a large drowned river mouth tributary of the St Lawrence River. Prior to habitat modifications, the coastal wetland was impaired by water level regulations and dominance of the invasive hybrid cattail, Typha × glauca, which collectively replaced or created barriers to seasonally flooded spawning habitats important to fish. Connectivity enhancements provided fish access along a wetland habitat gradient from sedge-meadows to the deeper water robust emergent main channel. Across an 8-year fish emigration dataset (2012, 2013, 2016-2021) more than 90% of all captured fish (Ntotal  = 218,086 fish) were YOY and modified habitats outperformed the unmodified channels in total fish catch-per-unit-effort (CPUE) per year (both YOY and non-YOY). Spawning pool complexes had higher YOY species richness than unmodified channel habitats. Fish assemblage structure differed between the modified habitats, where connectivity channels and unmodified channels shared a more similar fish assemblage than spawning pool complexes. Modified habitats, however, supported warmer water and higher dissolved oxygen than the unmodified channels. Redundancy analysis and linear mixed-effect modelling with abiotic variables (hydrology, temperature and dissolved oxygen) showed significant effects on fish assemblage structure, species richness and CPUE of fish emigrating from the modified and unmodified habitats. Historic flooding in 2017 and 2019 was a primary driver of YOY fish production and fish assemblage structure, but also appeared to be associated with near anoxic conditions systemwide. YOY fish for several species was inversely affected by floods at spawning pool complexes, but CPUE of YOY fish for these species appeared unaffected at the connectivity channels despite low dissolved oxygen. Diversified habitat structure (i.e., connectivity channels and spawning pool complexes) offers a management option to enhance habitat for fish that allowed compensatory effects on the capture of YOY fish of several species during floods. This multifaceted outcome from the habitat modifications resulted in unique fish assemblages between the channelized and spawning pool habitat. A connectivity-based habitat enhancement strategy provides adaptability for an uncertain climatic and regulatory future for the Laurentian Great Lakes and St Lawrence River.

Influence of seasonal variation to the population growth and ecophysiology of Typha domingensis (Typhaceae)

Precipitation is an important climatic element that defines the hydrological regime, and its seasonal variation produces annual dry and wet periods in some areas. This seasonality changes wetland environments and leverages the growth dynamics of macrophytes present, including Typha domingensis Pers. This study aimed to evaluate the influence of seasonal variation on the growth, anatomy and ecophysiology of T. domingensis in a natural wetland. Biometric, anatomical and ecophysiological traits of T. domingensis were evaluated over one year at four-month intervals. Reductions in photosynthesis were evidenced at the end of the wet periods and during the dry periods, and these reductions were associated with thinner palisade parenchymas. Increased stomatal indexes and densities as well as thinner epidermis observed at the beginning dry periods can be associated with higher transpiration rates during this period. The plants maintained their water contents during the dry periods, which may be related to the storage of water in leaf trabecular parenchyma, as this is the first time that results indicate the function of this tissue as a seasonal aquiferous parenchyma. In addition, increasing proportions of aerenchymas were evident during the wet periods, which may be related to a compensation mechanism for soil waterlogging. Therefore, the growth, anatomy and ecophysiology of T. domingensis plants change throughout the year to adjust to both the dry and wet periods, providing conditions for the survival of the plants and modulating population growth.

Emergent (branched bur-reed-Sparganium erectum L.) and submergent (river water-crowfoot-Ranunculus fluitans Wimm., 1841) aquatic plants as metal biosorbents under varying water pH conditions in laboratory conditions

A laboratory experiment was performed to find out the potential bioaccumulation of metals (Al, Cu, Cd, Ni, Pb, Fe, Mn) in aquatic plants acting as natural biosorbents in the environment depending on the variation of water pH. Two plants were selected for the study: branched bur-reed-Sparganium erectum L., as a representative of emergent plants; and river water-crowfoot-Ranunculus fluitans Wimm., 1841, as a representative of submergent plants. The bioaccumulation of metals in plants relative to water (BCFW) was determined, and the metal pollution index (MPI) was calculated. The metal content in water and plants before the experiment was arranged in the following series of increasing values: Cd = Ni < Cu < Pb < Mn < Al < Fe (water) and Cd < Cu < Ni < Pb < Al < Fe < Mn (in both plants). The lowest concentration of cadmium was found in water both at the end and beginning of the experiment. In turn, aluminum level increased, and its concentration was the highest in both acidic and alkaline water. This suggests that aluminum is definitely more available to the organisms living in it under such conditions, and in higher concentrations may be a limiting factor for them. Bioaccumulation of metals (BCFW) in neutral and alkaline environments was higher in branched bur-reed, and in acidic conditions in river water-crowfoot. This may provide a basis for using specific plant species to selectively accumulate metals depending on the range of water pH. This is also supported by the MPI values, which indicate that they have a very high and often the highest impact on metal pollution levels. The observed variability of metals bioaccumulation against the condition of hydromacrophytes makes it possible to consider these plants as biosorbents used in constructed biological treatment plants, which, depending on the species placed there, can selectively absorb particular trace elements. The plants used in the experiment are common hydromacrophytes of Europe, so they can be used in the construction of artificial wetlands across the continent. The apparent diversity of metal accumulation in relation to hydromacrophytes indicates that this type of site can be inhabited by specific species, which can significantly improve the purification of natural or anthropogenic water reservoirs, i.e., those that are intended to perform a filtering function.

The unexpected long period of elevated CH4 emissions from an inundated fen meadow ended only with the occurrence of cattail (Typha latifolia)

Drainage and agricultural use transform natural peatlands from a net carbon (C) sink to a net C source. Rewetting of peatlands, despite of high methane (CH4 ) emissions, holds the potential to mitigate climate change by greatly reducing CO2 emissions. However, the time span for this transition is unknown because most studies are limited to a few years. Especially, nonpermanent open water areas often created after rewetting, are highly productive. Here, we present 14 consecutive years of CH4 flux measurements following rewetting of a formerly long-term drained peatland in the Peene valley. Measurements were made at two rewetted sites (non-inundated vs. inundated) using manual chambers. During the study period, significant differences in measured CH4 emissions occurred. In general, these differences overlapped with stages of ecosystem transition from a cultivated grassland to a polytrophic lake dominated by emergent helophytes, but could also be additionally explained by other variables. This transition started with a rapid vegetation shift from dying cultivated grasses to open water floating and submerged hydrophytes and significantly increased CH4 emissions. Since 2008, helophytes have gradually spread from the shoreline into the open water area, especially in drier years. This process was periodically delayed by exceptional inundation and eventually resulted in the inundated site being covered by emergent helophytes. While the period between 2009 and 2015 showed exceptionally high CH4 emissions, these decreased significantly after cattail and other emergent helophytes became dominant at the inundated site. Therefore, CH4 emissions declined only after 10 years of transition following rewetting, potentially reaching a new steady state. Overall, this study highlights the importance of an integrative approach to understand the shallow lakes CH4 biogeochemistry, encompassing the entire area with its mosaic of different vegetation forms. This should be ideally done through a study design including proper measurement site allocation as well as long-term measurements.

Efficient removal of Cr(VI) and As(V) from an aquatic system using iron oxide supported typha biochar

The removal of Cr(VI) and As(V) from aqueous solutions has been a worldwide concern. In this study, Typha biochar (FBC) with magnetic iron oxide was prepared by impregnating Typha with FeCl₃ and performing pyrolysis, and the possible mechanism of Cr(VI) and As(V) removal was investigated by combining characterization means and adsorption experiments. The results showed that the modified Typha biochar is rich in pores and has the potential to eliminate Cr and As through processes such as exchange and reduction. The single molecule uptake capacities of FBC for Cr(VI) and As(V) were 32.82 and 21.56 mg g^-1, respectively. The adsorption process is spontaneous heat absorption, and the adsorption results are also consistent with the proposed secondary kinetic model. FBC still had >60% removal efficiency in the second and third reuse of Cr(VI), indicating its good recyclability. Therefore, this study confirms that FBC can effectively remove both Cr(VI) and As(V).

Structure characterization of pectin from the pollen of Typha angustifolia L. and the inhibition activity of lipid accumulation in oleic acid induced L02 cells

The pollen of Typha angustifolia L. decoction was clinically used to treat hyperlipidemia in China. A pectin polysaccharide (PTPS-2-2) was obtained from T. angustifolia pollen through water extraction, ion-exchange chromatography, and gel chromatography. Structural characterization showed that PTPS-2-2 had a molecular weight of 54 kDa and was composed of rhamnose, arabinose, xylose, galactose, and galacturonic acid with a molar ratio of 11.5: 36.5: 4.1: 36.7: 11.2. PTPS-2-2 consisted of rhamnogalacturonan I (RG-I) and arabinogalactan II (AG-II) domains. Its backbone was predominantly composed of →4-α-D-GalpA-(1 → 2)-α-L-Rhap-(1→, with branches of 1,3-Galp, 1,6-Galp, 1,3,6-Galp, T-Araf, 1.5-Araf and T-Xylp, connected to the 4-position of 1,2-Rhap and the 3-position of 1,4-GalpA. The inhibitory effect of PTPS-2-2 on lipid accumulation was studied in vitro, using L02 cells induced by oleic acid. This experiment shows that PTPS-2-2 treatment at 100-400 μg/mL dose-dependently reduce cellular triglycerides (TG), cholesterol (TC), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and malondialdehyde (MDA) levels, while elevated superoxide dismutase (SOD) levels. This indicated that PTPS-2-2 potentially ameliorated oleic acid-induced hepatic steatosis by inhibiting lipid accumulation and oxidative stress.

Ecological health risk assessment of microplastics and heavy metals in sediments, water, hydrophytes (Alternanthera philoxeroides, Typha latifolia, and Ipomoea carnea), and fish (Labeo rohita) in Marala wetlands in Sialkot, Pakistan

For the ecological risk assessment of heavy metals and microplastics in Marala wetlands in Sialkot, Pakistan, samples of sediments, water, aquatic plants (Alternanthera philoxeroides, Typha latifolia, and Ipomoea carnea), and fish (Labeo rohita) were studied from five different locations. Pb, Cd, and Cr concentrations were above permissible limits devised by WHO in sediments and water at most of sites. High concentrations of Cd were recorded in water samples compared to sediments with maximum values recorded at Site-2 (52.08 ± 9.55 mg kg-1) and Site-5 (62.29 ± 10.12 mg kg-1). The maximum concentrations of Cr (7.23 ± 0.40 mg kg-1) and Pb (22.87 ± 0.83 mg kg-1) were found at Site-4 in water samples. The maximum abundance of microplastics (3047 pieces kg-1 of sediments) was at Site-1 with filaments in the highest proportion among the other types. Zn, Ni, and Cu remained generally low in concentrations in both sediments and waters. Plants showed accumulation of heavy metals, notably the amount of Cd (33.36 ± 0.26 mgkg-1) and Ni (163.3 ± 1.30 mgkg-1) absorbed by T. latifolia and A. philoxeroides, respectively were high. Also, photosynthetic pigments in plants seemed to be affected. However, estimated daily intake (EDI) and provisional tolerable weekly intake (PTWI) calculations for the human population consuming fish from this wetland remained below the FAO/WHO limits. PCA analysis revealed the anthropogenic origin of metals that might be causing adverse effects on the biota which depend on this wetland for their food.

Biological pilot treatment reduces physicochemical and microbiological parameters of dairy cattle wastewater

The objectives of the present study were to characterize and evaluate a pilot treatment unit (PTU) for dairy cattle wastewater (DCW) in relation to its efficiency in reducing the physicochemical and microbiological parameters and possible application of this fertilizer in organic production. A PTU was set up, composed of the following elements: a dung pit of 7.8 m³, already in place; a septic tank; a set of anaerobic biological filters comprising an upflow filter and a downward-flow filter filled with fragments PVC corrugated conduit; and two constructed wetland systems (CWSs) of horizontal subsurface flow in two parallel routes (Routes 1 and 2), controlled by means of a flow rate divider box. Route 1 passed through CWS 1 cultivated with cattail (Typha domingensis) and Route 2 passed through CWS 2 cultivated with vetiver grass (Chrysopogon zizanioides). To evaluate the treatment stages, biweekly investigations were carried out to collect effluent samples. The results of monitoring, in absolute values, were evaluated by means of the medians and variation coefficients and compared by means of Kruskal-Wallis non-parametric test followed by the Student Newman Keuls test. The treatment efficiencies of Routes 1 and 2 were calculated. The influence of vetiver on the removal of nutrients from the DCW was analyzed and the productivity estimate (t.ha^-1) was performed. CWS 1 was not able to reduce the organic load indices, but it was able to retain fatty material and sodium. CWS 2 showed a reduction in nitrogenous forms and also for other nutrients, achieving the greatest removal of sodium and greatest decay of fecal contamination indicators, thermotolerant coliforms (56.13%), and E. coli (46.82%).

Phytoremediation capability of Typha latifolia L. to uptake sediment toxic elements in the largest coastal wetland of the Persian Gulf

The present study evaluated the status of sediment toxicity and pollution, and the phytoremediation capability of Typha latifolia L. (TlL) within the largest coastal wetland in the southwest of Iran, the Shadegan International Wetland. In eight sampling sites, covering the entire wetland, the concentration of six toxic elements (As, Cr, Cu, Ni, Pb, and Zn) in the surface sediment, root, and stem of TlL were measured. The results indicated that mean concentrations of Cr, Cu, Pb, and Zn were found to be higher than those in the local background, which likely indicates anthropogenic sources of these elements. Due to the presence of a nearby landfill, the results of modified pollution index (MPI) and aggregate toxicity index (ATI) indicated a moderately-heavily polluted level and moderate to high toxic degree, respectively. However, the medium-low level of toxicity toward living of organisms (21 % probability) was detected based on the assessment of the Sediment Quality Guidelines (SGQ). The results of our study indicate that the root and stem tissues of TlL are capable of acting as an indicator of Cu/Pb/Zn and Zn pollution in sediment, respectively. Considering the potential of phytoremediation, TlL represented both phytostabilization and phytoextraction capabilities for Pb and Zn and a significant increase was observed in the phytoremediation capability by increasing the distance from the landfill area. According to the results of the metal accumulation index (MAI) and comprehensive bioconcentration index (CBCI), TlL grown in the study area showed an acceptable performance in the accumulation of multiple toxic elements compared to that in Turkey, India, and Poland. Overall, TlL is a good candidate for the phytoremediation of sediments contaminated by Pb and Zn.

Ecological Processes of Bacterial and Fungal Communities Associated with Typha orientalis Roots in Wetlands Were Distinct during Plant Development

Root-associated microbiomes are essential for the ecological function of the root system. However, their assembly mechanisms in wetland are poorly understood. In this study, we explored and compared the ecological processes of bacterial and fungal communities in water, bulk soil, rhizosphere soil, and root endosphere niches for 3 developmental stages of Typha orientalis at different wetland sites, and assessed the potential functions of root endosphere microbiomes with function prediction. Our findings suggest that the microbial diversity, composition, and interaction networks along the water-soil-plant continuum are shaped predominantly by compartment niche and developmental stage, rather than by wetland site. Source tracking analysis indicated that T. orientalis' root endosphere is derived primarily from the rhizosphere soil (bacteria 39.9%, fungi 27.3%) and water (bacteria 18.9%, fungi 19.1%) niches. In addition, we found that the assembly of bacterial communities is driven primarily by deterministic processes and fungal communities by stochastic processes. The interaction network among microbes varies at different developmental stages of T. orientalis, and is accompanied by changes in microbial keystone taxa. The functional prediction data supports the distribution pattern of the bacterial and fungal microbiomes, which have different ecological roles at different plant developmental stages, where more beneficial bacterial taxa are observed in the root endosphere in the early stages, but more saprophytic fungi in the late stages. Our findings provide empirical evidence for the assembly, sources, interactions, and potential functions of wetland plant root microbial communities and have significant implications for the future applications of plant microbiomes in the wetland ecosystem. IMPORTANCE Our findings provide empirical evidence for the assembly, sources, interactions, and potential functions of wetland plant root microbial communities, and have significant implications for the future applications of plant microbiomes in the wetland ecosystem.

A reappraisal of the phylogeny and historical biogeography of Sparganium (Typhaceae) using complete chloroplast genomes

BACKGROUND

Sparganium (Typhaceae) is a widespread temperate genus of ecologically important aquatic plants. Previous reconstructions of the phylogenetic relationships among Sparganium species are incompletely resolved partly because they were based on molecular markers comprising < 7,000 bp. Here, we sequenced and assembled the complete chloroplast genomes from 19 Sparganium samples representing 15 putative species and three putative subspecies in order to explore chloroplast genome evolution in this genus, clarify taxonomic lineages, estimate the divergence times of Sparganium species, and reconstruct aspects of the biogeographic history of the genus.

RESULTS

The 19 chloroplast genomes shared a conserved genome structure, gene content, and gene order. Our phylogenomic analysis presented a well-resolved phylogeny with robust support for most clades. Non-monophyly was revealed in three species: S. erectum, S. eurycarpum, and S. stoloniferum. Divergence time estimates suggest that the two subgenera of Sparganium split from each other ca. 30.67 Ma in the middle Oligocene. The subgenus Xanthosparganium diversified in the late Oligocene and Miocene, while the subgenus Sparganium diversified in the late Pliocene and Pleistocene. Ancestral area reconstruction suggested that the two subgenera may have originated in East Eurasia and North America.

CONCLUSION

The non-monophyletic nature of three putative species underscores the necessity of taxonomic revision for Sparganium: S. stoloniferum subsp. choui may be more appropriately identified as S. choui, and subspecies of S. erectum may be in fact distinct species. The estimated diversification times of the two subgenera correspond to their species and nucleotide diversities. The likely ancestral area for most of subgenus Xanthosparganium was East Eurasia and North America from where it dispersed into West Eurasia and Australia. Most of subgenus Sparganium likely originated in North America and then dispersed into Eurasia. Our study demonstrates some of the ways in which complete chloroplast genome sequences can provide new insights into the evolution, phylogeny, and biogeography of the genus Sparganium.

Assessment of heavy metal accumulation potential of aquatic plants for bioindication and bioremediation of aquatic environment

This study is devoted to assessing the potential for accumulating heavy metals (Fe, Mn, Cu, Zn) of nine species of aquatic and coastal plants growing in the water area of the Okhta River (St. Petersburg, Russian Federation). The list of studied species included the following: hornwort (Ceratophyllum demersum L.), water soldier (Stratiotes aloides L.), yellow water-lily (Nuphar lutea (L.) Sm.), arrowhead (Sagittaria sagittifolia L.), broadleaf cattail (Typha latifolia L.), water arum (Calla palustris L.), acute sedge (Carex acuta L.), reed canary grass (Phalaris arundinacea L.), and meadowsweet (Filipendula ulmaria (L.) Maxim.). The values of the bioconcentration factor for particular plant tissues were calculated. It has been established that the concentrations of metals in plant tissues can be thousands and tens of thousands of times higher than their content in water. At the same time, the ability of plants to accumulate metals varies greatly and depends on a number of factors, such as environmental conditions, the growing season, the type and ecological group of the plant.The study also attempts to determine the spatial and temporal dynamics of the content of heavy metals in higher aquatic plants. The main difficulties in data interpretation are indicated. The data obtained show the different significance of the study macrophyte species both for bioindication purposes and for use in wastewater treatment. The possibility of using such species as Sagittaria sagittifolia L., Typha latifolia L., Ceratophyllum demersum L., and Calla palustris L. for bioremediation is substantiated.

A neoteric approach for the complete valorization of Typha angustifolia leaf biomass: A drive towards environmental sustainability

Exploring new biomass resources and developing a sustainable process for holistic utilization has become crucial due to the high demand for bio-based chemicals as alternatives to petrochemicals. Herein, we describe a novel approach to valorize the Typha angustifolia leaves, underutilized biomass into cellulose, hemicellulose and lignin nanoparticles. The process was framed in a sequence to isolate hemicellulose in the first step due to its highly reactive nature and then separate cellulose and lignin. Among the various natural deep eutectic solvents used in screening experiments, LA/ChCl (2:1) was chosen for hemicellulose solubilization and a dissolution yield of 95.97 ± 1.8% was obtained in 30 min at 240 W microwave power. Then the residual solid was delignified using NaOCl₂ at 180 W microwave power and a yield of 97 ± 0.75% was obtained in 15 min. Dissolved hemicellulose and lignin were precipitated using anti-solvents. The proposed approach achieved a recovery yield of 95.5 ± 1.2% cellulose, 91.9 ± 2.6% hemicellulose and 89.5 ± 1.6% lignin. Subsequently, the isolated particles were converted into nanoparticles by intense ultrasonication. Spherical shaped nanocellulose, nanohemicellulose and nanolignin were obtained with an average size of 76 ± 7 nm, 86 ± 9 nm, and 64 ± 5 nm, respectively. The produced nanocellulose had a crystallinity of 77.36% with the thermal stability of 265 °C. Nanohemicellulose and nanolignin were found to be semicrystalline with thermal stability up to 245 °C and 275 °C, respectively. The characterization results of the nanoparticles isolated from Typha angustifolia leaves are indicative of their wide range of biomedical and material science applications. This research could open a window for complete utilization of biomass in biorefinery and sustainable management of an invasive plant Typha angustifolia.

A pilot system integrating a settling technique and a horizontal subsurface flow constructed wetland for the treatment of polluted lake water

An integrated system was tested at pilot-scale for treating polluted water from the Marriot Lake in Egypt, comprising a settling technique followed by three parallel horizontal subsurface flow constructed wetland (HFCWs) units operating under a continuous flow mode; one HFCW unit was planted with Typha angustifolia and contained a perforated pipes network for enhanced passive aeration (CWA), one unit was planted without the perforated pipe network (CWR) and one served as a Control unit (unplanted and without perforated pipes). Changes in physicochemical parameters, BOD₅, nutrients (nitrogen, phosphorus), microbial community, and trace metals at different hydraulic retention times (HRT; 0.5-6 h) and hydraulic loading rates (HLR; 750, 1000, 1250, and 2000 L/m²/d) were monitored. The CWA unit had an overall better performance than the CWR unit, while both planted units outperformed the Control unit. CWA showed the highest performance at HLR of 1000 L/m²/d and 4-6 h-HRT with 95.3% removal for turbidity, 83% for BOD₅, 99.3% for ammonia nitrogen (NH₄-N), 70.8% for Total Nitrogen (TN), and 66.7% for Total Phosphorus (TP), while higher NO₃-N and NO₂-N effluent concentrations were observed. Trace metals levels were significantly reduced and accumulated in plant tissues. Microbial communities' densities fluctuated in the CWA unit. The integrated system with the settling stage and the planted CWA unit was proved to achieve a high removal efficiency and reached the national discharge limits, thus representing a novel nature-based solution for the sustainable remediation of polluted lake water.

Iron hazard in an impacted estuary: Contrasting controls of plants and implications to phytoremediation

Due to its abundance and role as a micronutrient for plants iron (Fe) is rarely perceived as a contaminant. However, in redox active environments, Fe bioavailability increases sharply representing an environmental risk. In this study, a recent catastrophic mining dam failure is used as a field framework to evaluate the role of wetland plants on Fe biogeochemistry and assess their potential for phytoremediation programs. To achieve these objectives, a Fe geochemical partitioning and the concentration of Fe in different plant compartments (iron plaque on root surfaces, roots, and leaves) were determined in two sites vegetated by different wetland species. Soils exhibited contrasting Fe biogeochemical dynamics. Lower pseudo-total contents and more reactive Fe oxides were observed in the soil vegetated by Typha domingensis. Iron plaque was present on both species but more concentrated in Fe in T. domingensis. T. domingensis showed Fe shoot concentrations (3874 mg kg^-1) 10-fold higher than in Hibiscus tiliaceus, which prevented Fe absorption through iron plaque formation and root accumulation. In conclusion, contrasting biogeochemical effects on Fe (e.g., rhizosphere acidification) lead to different phytoremediation abilities. T. domingensis showed a high potential for Fe phytoremediation on sites affected by Fe-enriched wastes and should be tested in assisted phytoremediation approaches.

Internalisation of Salmonella spp. by Typha latifolia and Cyperus papyrus in vitro and implications for pathogen removal in Constructed Wetlands

ABSTRACTFreshwater contamination by enteric pathogens is implicated in the high frequency of diarrhoeal diseases in low to middle income countries, typically due to poor wastewater management. Constructed Wetlands are a cost-effective and sustainable alternative to conventional/mechanical treatment technologies, but the pathogen removal mechanisms in Constructed Wetlands are not fully understood. This study investigated for the first time the internalisation of Salmonella spp. by Typha latifolia and Cyperus papyrus in hydroponic microcosms. Presence of Salmonella spp. within roots, rhizomes and shoots was assayed using agar-based methods over a period of 12 days. Concentration of Salmonella spp. in growth media showed 2.7 and 4.8 log unit reduction with T. latifolia and C. papyrus, respectively, and 1.8 and 6.0 log unit in unplanted units. Salmonella spp. was recovered from root and rhizome tissues of T. latifolia (up to 4.4 logCFU/g) and C. papyrus (up to 3.4 logCFU/g), and the bacteria were highly concentrated in the epidermis and cortex. However, Salmonella spp. was not detected in the stems and leaves of the two plant species. The present study demonstrates for the first time that these macrophytes internalise cells of Salmonella spp., which could be one pathogen removal mechanism employed by wetland plants.

Root anatomy, growth, and development of Typha domingensis Pers. (Typhaceae) and their relationship with cadmium absorption, accumulation, and tolerance

Typha domingensis Pers. is a plant that grows in marshy environments, where cadmium (Cd) accumulates. The root is the first organ that comes into contact with the metal. The aim of this study was to evaluate the effect of Cd on the roots of T. domingensis. The experiment was conducted in a greenhouse using different Cd concentrations: (1) 0 µM (control), (2) 10 µM, and (3) 50 µM, with 10 replicates for 90 days. The plants were placed in plastic containers containing 5 L of nutrient solution modified with the different Cd concentrations. At the end of the experiment, the roots were measured, sampled, fixed, and subjected to usual plant microtechniques. The slides were observed and photographed under light microscopy and analyzed in ImageJ software. To measure Cd absorption, atomic-absorption spectrometry was used. The data were subjected to analysis of variance and comparison of means by the Scott-Knott test at P < 0.05. When exposed to 50 µM of Cd, the roots accumulated 99.35% of the Cd. At this concentration, there was a reduction in the exodermis but there was an increase in the diameter of the cortical cells and in the proportion of aerenchyma in the cortex. There was an increase in the root cap, which guaranteed the protection of the primary meristems. Therefore, T. domingensis adjusts its root anatomy improving the Cd tolerance and shows potential for phytoremediation purposes.

Removal of tramadol from water using Typha angustifolia and Hordeum vulgare as biological models: Possible interaction with other pollutants in short-term uptake experiments

Tramadol (TRD) is widely detected in aquatic ecosystems as a result of massive abuse and insufficient removal from wastewater facilities. As a result, TRD can contaminate groundwater sources and/or agricultural soils. While TRD toxicity has been reported from aquatic biota, data about TRD detection in plants are scarce. Moreover, information regarding plant capability for TRD removal is lacking. To understand the fate of this opioid, we have investigated the uptake, translocation and removal capacity of TRD by plants, addressing short-term and long-term uptake. The uptake rates of TRD, in excised barley and cattail roots, were 5.18 and 5.79 μg g^-1 root fresh weight day^-1, respectively. However, TRD uptake was strongly inhibited after co-exposing these roots either with the drug venlafaxine (similar molecular structure as TRD) or with quinidine (an inhibitor of cellular organic cation transporters). When barley seedlings were exposed to TRD in a hydroponic experiment a removal efficiency up to 90% (within 15 days) was obtained, with bioconcentration and translocation factors close to 9 and 1, respectively. The combination of results from both plants and the inhibition observed after treatment with quinidine revealed that organic cation transporters may be involved in the uptake of TRD by plants.

Distribution of the heavy metals Co, Cu, and Pb in sediments and Typha spp. And Phragmites mauritianus in three Zambian wetlands

Zambia has been mining cobalt (Co), copper (Cu), and lead (Pb) for over a century, with discharges entering wetlands without investigations on the level of sediment pollution and how to solve it. This present study investigated: 1) the extent to which Co, Cu, and Pb that enter through mining wastewater were distributed in the sediment of three wetlands (Uchi, Mufulira, and Kabwe) in Zambia and 2) the accumulation and distribution of the heavy metals in two emergent wetland plants, Phragmites mauritianus, and Typha spp. in order to evaluate their potential for phytoremediation of metals. Samples from three sections (inlet, middle section and outlet) of each wetland were analyzed for the heavy metal contents. Sediment contents of Co and Cu were significantly higher in the Uchi wetland than in the other two, while Pb was significantly higher in the Kabwe wetland. Cu in all the wetlands were found to be at levels considered a threat to aquatic life, with Pb contents in Kabwe a risk to human health. Both P. mauritianus and Typha spp acted as excluder species for Co, Cu, and Pb, showing bioaccumulation factor (BAF) < 1 and Translocation factor (TF) < 1 for all wetlands. As neither species accumulated cellularly toxic concentrations of Co, Cu, and Pb, they could grow in the contaminated sediments. Currently, methods used to solve historic mining impacts in Zambian wetlands aim at improving water flow and reducing flooding without attending to the heavy metal contents of the sediments. From this study, P. mauritianus and Typha spp. provide the potential for phytostabilisation to settle and contain polluted sediments.

Aquatic macrophytes mitigate the short-term negative effects of silver nanoparticles on denitrification and greenhouse gas emissions in riparian soils

Silver nanoparticles (AgNPs) are increasingly released into the aquatic environments because of their extensive use in consumer products and industrial applications. Some researchers have explored the toxicity of AgNPs to nitrogen (N) and carbon (C) cycles, but little is known about the role of aquatic plants in regulating the impact of AgNPs on these biogeochemical processes and related microorganisms. Here, two 90-day pot experiments were conducted to determine the effect of AgNPs on denitrification rates and greenhouse gas emissions in riparian wetland soils, with or without emergent plants (Typha minima Funck). As a comparison, the toxicity of equal concentration of AgNO₃ was also determined. The results showed that AgNPs released a great quantity of free Ag⁺, most of which was accumulated in soils, while little (less than 2%) was absorbed by plant shoots and roots. Both AgNPs and AgNO₃ could increase the soil redox potential and affect the growth and nutrient (N and phosphorus) uptake of plants. In soils with plants, there was no significant difference in denitrification rates and emissions of N₂O and CH₄ between control and AgNPs or AgNO₃ treatments at all tested concentrations (0.5, 1 and 10 mg kg^-1). However, low levels of AgNPs (0.5 mg kg^-1) significantly enhanced CO₂ emission throughout the experiment. Interestingly, in the absence of plants, a high dosage (10 mg kg^-1) of AgNPs generally inhibited soil denitrification and stimulated the emissions of CO₂, CH₄ and N₂O in the short-term. Meanwhile, the abundance of key denitrifying genes (nirS and nirK) was significantly increased by exposure to 10 mg kg^-1 AgNPs or AgNO₃. Our results suggest that emergent plants can alleviate the short-term negative effects of AgNPs on N and C cycling processes in wetland soils through different pathways.

Investigation on the performance evaluation of vertical subsurface flow constructed wetland for the treatment of rural wastewater

In a rural country like India, low cost and decentralized treatment units like the vertical subsurface flow constructed wetland (VSSF CW) can be reflected as a novel wastewater system. In this concern, a pilot-scale VSSF CW unit of size 0.92 m × 0.92 m × 0.85 m bed planted with Typha latifolia and Phragmites australis was operated for a 12-month duration to treat simulated rural wastewater. During the operation, a constant head arrangement was made to maintain a continuous flow to achieve 5 different Hydraulic Retention Times (HRTs) of 2, 4, 6, 8 and 10 days in each season, such as winter, summer and rainy, to investigate the performance of the unit under different retention times. The reactor showed optimum removal efficiency at 6 days HRT at 12.5 cm/day Hydraulic Loading Rate (HLR) for organic matter removal. Both macrophytes and the microbial biomass of filter media effectively treated the rural wastewater. Average removal efficiency of the reactor during the entire study was 64.73%-88.80% for Chemical Oxygen Demand, 74.96%-95.34% for Biochemical Oxygen Demand, 40.13%-79.45% for Ammonia Nitrogen, 25.36%-65.65% for Total Kjeldahl Nitrogen, 22.86%-58.48% for Phosphate phosphorus, 23.50%-55.45% for Total phosphorous, 74.91%-98.59% for Faecal Coliforms and 71.14%-95.31% for Total Coliforms respectively. Two-way ANOVA followed by post-hoc Tukey's test showed that HRT had a significant impact on removal efficiency but not the season. Overall performance of the unit was good and study suggested that VSSF CW can be a smart alternative technology to treat rural wastewater before final disposal.

Atrazine uptake, translocation, bioaccumulation and biodegradation in cattail (Typha latifolia) as a function of exposure time

The extensive use and environmental persistence of atrazine has resulted in its ubiquitous occurrence in water resources. Some reports have described atrazine bioaccumulation and biodegradation pathways in terrestrial plants, but few have done so in aquatic macrophytes. Thus, in this study, we aimed to analyze morphological changes, uptake, translocation and bioaccumulation patterns in tissues of the aquatic macrophyte Typha latifolia (cattail) after long-term atrazine exposure and to determine the presence of atrazine biodegradation metabolites, desethylatrazine (DEA) and desisopropylatrazine (DIA), in tissues. Plants were hydroponically exposed to 20 μg/L atrazine (18 exposed and 18 non-exposed) for 7, 14, 21, 28, 35 and 42 days. Plants were separated into root, rhizome, stem, and lower, middle and upper leaf sections. Atrazine was analyzed by LC-MS/MS and DIA and DEA by LC-DAD. Plants showed reductions in weight (after 21 days) and transpiration (after 28 days), both symptoms of chronic phytotoxicity. The distribution of atrazine within tissues, expressed as concentration levels (μg/kg dry weight), was as follows: middle leaf (406.10 ± 71.77) = upper leaf (339.15 ± 47.60) = lower leaf (262.43 ± 7.66) = sprout (274.53 ± 58.1) > stem (38.63 ± 7.55) = root (36.00 ± 3.49) = rhizome (26.15 ± 3.96). In submerged tissues, DEA and DIA were detected at similar concentrations. In leaves, DIA was the main metabolite identified. Results indicated that atrazine was taken up from roots to shoots and induced phytotoxicity effects that reduced the translocation to shoots. Typha likely is able to biodegrade atrazine via different metabolic pathways.

Phytoremediation of heavy metals and total petroleum hydrocarbon and nutrients enhancement of Typha latifolia in petroleum secondary effluent for biomass growth

Phytoremediation is an innovative tool which can be used for the treatment of industrial and agricultural wastewater. Typha latifolia (T. latifolia) is an aquatic plant used for phytoremediation of heavy metals (HMs) like cadmium (Cd), cobalt (Co), manganese (Mn), and TPH (total petroleum hydrocarbon) for the treatment of petroleum secondary effluent (PSE). During this experiment, the growth of T. latifolia in biomass, nutrient concentrations, and heavy metals were studied. The results indicated that T. latifolia was more tolerant to Cd, Co, and Mn due to its transfer index (TI) which was found to be greater than 2.9. The enrichment coefficients of the metals, Cd and Co present in the root were found to be higher than 3.31 to 2.56 and 5.35 to 3.55, respectively unlike the stem of T. latifolia. But, the enrichment coefficient of Mn was found to be 1.98 which was expected to be 3.51 at 75%. Similarly, the enrichment coefficients of all the metals, except for Co, in roots of T. latifolia were higher than 5.36. (TI) for Co (2.95) and Mn (2.55) which is better as compared to the enrichment coefficients of Cd (2.35) and TPH (3.45) in PSE. Thus, there is a possibility that PSE could be a source of important nutrients.

Biochar composite with microbes enhanced arsenic biosorption and phytoextraction by Typha latifolia in hybrid vertical subsurface flow constructed wetland

Arsenic contamination of ground water is a worldwide issue, causing a number of ailments in humans. As an engineered and integrated solution, a hybrid vertical subsurface flow constructed wetland (VSSF-CW) amended with BCXZM composite (Bacillus XZM immobilized on rice husk biochar), was found effective for the bioremediation of arsenic contaminated water. Biological filter was prepared by amending top 3 cm of VSSF-CW bed with BCXZM. This filter scavenged ∼64% of total arsenic and removal efficiency of ∼95% was achieved by amended and planted (As + P + B) VSSF-CW, while non-amended (As + P) VSSF-CW showed a removal efficiency of ∼55%. The unplanted and amended (As + B) VSSF-CW showed a removal efficiency of ∼70%. The symbiotic association of Bacillus XZM, confirmed by SEM micrographs, significantly (p ≤ 0.05) reduced reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation in Typha latifolia, hence, increasing the plant growth (2 folds). An increase in the indole acetic acid (IAA) and arsenic accumulation in plant was also observed in As + P + B system. The removal efficiency of the system was compromised after 4th consecutive cycle and 48 h was observed as optimum retention time. The FTIR-spectra showed the involvement of -N-H bond, carboxylic acids, -CH₂ stretching of -CH₂ and -CH_3, carbonyl groups, -C-H, C-O-P and C-O-C, sulphur/thiol and phosphate functional groups in the bio-sorption of arsenic by BCXZM filter. Our study is a first reported on the simultaneous phytoextraction and biosorption of arsenic in a hybrid VSSF-CW. It is proposed that BCXZM can be applied effectively in CWs for the bioremediation of arsenic contaminated water on large scale.

Potential for phytoremediation of neonicotinoids by nine wetland plants

Broad-spectrum insecticides such as neonicotinoids tend to accumulate and detrimentally impact natural ecosystems. Accordingly, we aimed to assess the neonicotinoid phytoremediation abilities of nine wetland plant species commonly used in constructed wetland systems: Acorus calamus, Typha orientalis, Arundo donax, Thalia dealbata, Canna indica, Iris pseudacorus, Cyperus alternifolius, Cyperus papyrus and Juncus effusus. We assessed their removal of six neonicotinoids and explored the mechanisms responsible for the observed removal in a 28-day experiment. The planted systems effectively removed the neonicotinoids, with removal efficiencies of 9.5-99.9%. Compared with the other neonicotinoids, imidacloprid, thiacloprid and acetamiprid were most readily removed in the planted systems. C. alternifolius and C. papyrus exhibited the best removal performance for all six neonicotinoids. Based on our assessment of mass balance, the main removal processes were biodegradation and plant accumulation. Plants can enhance neonicotinoid removal through enhancing biodegradation. The differences in transport and accumulation behaviors may be related to plant species and physicochemical properties of neonicotinoids. Further research is merited on the toxicity of neonicotinoids to plants and microorganisms and the metabolic pathways by which neonicotinoids are broken down in wetland systems.

Efficacy of Lemna minor and Typha latifolia for the treatment of textile industry wastewater in a constructed wetland under citric acid amendment: A lab scale study

Lead (Pb), copper (Cu) and chromium (Cr) are one of the most harmful heavy metals (HMs), entering into the food chain through the irrigation of crops with an industrial effluent. The present study was performed to evaluate the toxic effects of textile effluents and performance of citric acid (CA) on phytoextraction potential of Lemna minor L. and Typha latifolia L. in an artificially designed wetland. Different doses of textile wastewater (0, 25, 50, 75, and 100%) and CA (10 mM) were applied alone and in combination. Plants were harvested and the data was collected regarding agronomic traits, photosynthetic pigments, antioxidant enzymes, reactive oxygen species (ROS), electrolytic leakage (EL) and HMs uptake and accumulation. The results depicted that the concentration and accumulation of Cu, Pb and Cr in different parts of T. latifolia plant was increased with and without CA addition. The maximum concentration of Pb, Cu and Cr increased in leaves by 279, 240 & 171%, in stem by 192, 172 & 154%, and in roots by 224, 183 & 168%, respectively. Similarly, the accumulation of Pb, Cu and Cr increased in leaves by 91, 71 & 36%, in stem by 57, 46 & 36% and in roots by 76, 53 & 45%, respectively in plants treated with 100% textile effluent as compared to the 25% textile effluent treated plants under CA amendment. In L. minor, the concentration of Pb, Cu & Cr increased by 542, 411 and 397% while accumulation increased by 101, 59 & 55% respectively in overall plant biomass.

Paludiculture as paludifuture on Dutch peatlands: An environmental and economic analysis of Typha cultivation and insulation production

Paludiculture, the cultivation of crops on rewetted peatlands, is often proposed as a viable climate change mitigation option that reduces greenhouse gas emissions (GHGe), while simultaneously providing novel agricultural business options. In West Europe, experiments are ongoing in using the paludicrop cattail (Typha spp.) as feedstock for insulation panel material. Here, we use a Dutch case study to investigate the environmental potential and economic viability of shifting the use of peat soils from grassland (for dairy production) to Typha paludiculture (for cultivation and insulation panel production). Using a life cycle assessment and cost-benefit analysis, we compared the global warming potential (GWP), yearly revenues and calculated Net Present Value (NPV) of 1 ha Dutch peat soil used either for dairy production or for Typha paludiculture. We estimated that changing to Typha paludiculture leads to a GWP reduction of ~32% (16.4 t CO₂-eq ha^-1), mainly because of lower emissions from peat decomposition as a result of land-use management (-21.6 t CO₂-eq ha^-1). If biogenic carbon storage is excluded, the avoided impact of conventional insulation material is insufficient to compensate the impact of cultivating and processing Typha (9.7 t CO₂-eq ha^-1); however, this changes if biogenic carbon storage is included (following PAS2050 guidelines). Typha paludiculture is currently not competitive with dairy production, mainly due to high cultivation costs and low revenues, which are both uncertain, and will likely improve as the system develops. Its NPV is negative, mainly due to high investment costs. This can be improved by introducing carbon credits, with carbon prices for Typha paludiculture (30 years) comparable to EU-ETS prices. In conclusion, Dutch Typha paludiculture has a significant climate change mitigation potential by reducing emissions from deep drained peatlands. Nevertheless, attention is needed to increase its economic viability as this is a key aspect of the system change.

Se transformation and removal by a cattail litter treatment system inoculated with sulfur-based denitrification sludge: Role of the microbial community composition under various temperature and aeration conditions

With a narrow margin between deficiency and toxicity, rising levels of selenium (Se) are threatening aquatic ecosystems. To investigate the role of microorganisms in Se bioremediation, a cattail litter system inoculated with the sulfur-based denitrification sludge was conducted. The results show the litter, as a carrier and nutrient source for bacteria, efficiently removed Se by ~ 97.0% during a 12-d treatment with water circulating. As the major removal pathways, immobilization rates of selenite were ~ 2.9-fold higher than selenate, and the volatilization, contributing to ~ 87.7% of the total Se removal, was significantly correlated with temperature (positively) and oxidation-reduction potential (ORP; negatively). Using X-ray absorption spectroscopy to speciate litter-borne Se, more Se⁰ formed without aeration due to abundant Se-reducing bacteria, among which Azospira and Azospirillum were highly related to the removal of both Se oxyanions, while Desulfovibrio, Azoarcus, Sulfurospirillum, Thauera, Geobacter, Clostridium, and Pediococcus were the major contributors to selenate removal. Overall, our study suggests microbial Se metabolism in the litter system was significantly affected by temperature and ORP, which could be manipulated to enhance Se removal efficiency and the transformation of selenate/selenite into low toxic Se⁰ and volatile Se, reducing risks posed by the residual Se in the system.

Repeated large-scale mechanical treatment of invasive Typha under increasing water levels promotes floating mat formation and wetland methane emissions

Invasive species management typically aims to promote diversity and wildlife habitat, but little is known about how management techniques affect wetland carbon (C) dynamics. Since wetland C uptake is largely influenced by water levels and highly productive plants, the interplay of hydrologic extremes and invasive species is fundamental to understanding and managing these ecosystems. During a period of rapid water level rise in the Laurentian Great Lakes, we tested how mechanical treatment of invasive plant Typha × glauca shifts plant-mediated wetland C metrics. From 2015 to 2017, we implemented large-scale treatment plots (0.36-ha) of harvest (i.e., cut above water surface, removed biomass twice a season), crush (i.e., ran over biomass once mid-season with a tracked vehicle), and Typha-dominated controls. Treated Typha regrew with approximately half as much biomass as unmanipulated controls each year, and Typha production in control stands increased from 500 to 1500 g-dry mass m^-2 yr^-1 with rising water levels (~10 to 75 cm) across five years. Harvested stands had total in-situ methane (CH₄) flux rates twice as high as in controls, and this increase was likely via transport through cut stems because crushing did not change total CH₄ flux. In 2018, one year after final treatment implementation, crushed stands had greater surface water diffusive CH₄ flux rates than controls (measured using dissolved gas in water), likely due to anaerobic decomposition of flattened biomass. Legacy effects of treatments were evident in 2019; floating Typha mats were present only in harvested and crushed stands, with higher frequency in deeper water and a positive correlation with surface water diffusive CH₄ flux. Our study demonstrates that two mechanical treatments have differential effects on Typha structure and consequent wetland CH₄ emissions, suggesting that C-based responses and multi-year monitoring in variable water conditions are necessary to accurately assess how management impacts ecological function.

Foliar architecture and physio-biochemical plasticity determines survival of Typha domingensis pers. Ecotypes in nickel and salt affected soil

Six ecotypes of Typha domingensis Pers. Jahlar (E₁), Sheikhupura (E₂), Sahianwala (E₃), Gatwala (E₄), Treemu (E₅) and Knotti (E₆) from different ecological regions were collected to evaluate the leaf anatomical and biochemical attributes under different levels of salinity and nickel stress viz; L₀ (control), L₁ (100 mM + 50 mg kg^-1), L₂ (200 mM + 100 mg kg^-1) and L₃ (300 mM + 150 mg kg^-1). Presence of salt and Ni in rooting medium consistently affected growth, anatomical and physio-biochemical attributes in all Typha ecotypes. Discrete anatomical modifications among ecotypes such as reduced leaf thickness, increased parenchyma area, metaxylem cell area, aerenchyma formation and improved metaxylem vessels were recorded with increasing dose of salt and Ni. The minimum anatomical damages were recorded in E₁ and E₆ ecotypes. In all ecotypes, progressive perturbations in ionic homeostasis (Na⁺, K⁺, Cl^-, N) due to salt and metal toxicity were evident along with reduction in photosynthetic pigments. Maximum enhancement in Catalase (CAT), Superoxide dismutase (SOD), Peroxidase (POD) and modulated Malondialdehyde (MDA) activity was recorded in E₁ and E₆ as compared to other ecotypes. Accumulation of large amounts of metabolites such as total soluble sugars, total free amino acids content in Jahlar, Knotti, Treemu and Sahianawala ecotypes under different levels of salt and Ni prevented cellular damages in T. domingensis Pers. The correlation analysis exhibited a close relationship among different levels of salinity and Ni with various plant attributes. PCA-Biplot verified our correlational analysis among various attributes of Typha ecotypes. An obvious separation of Typha characters in response to different salinity and Ni levels was exhibited by PC1. We recommend that genetic potential of T. domingensis Pers. To grow under salt and Ni stresses must be investigated and used for phytoremediation and reclamation of contaminated soil.

Production and modification of hydrochar from anaerobically digested cattail for adsorbing ammonium and phosphorous in wastewater

Water contamination by nitrogen and phosphorus ions has a direct consequence of eutrophication to the ecosystem. The objective of this study is to investigate the production of hydrochars by acetic acid or sodium hydroxide assisted hydrothermal carbonization (HTC), various activation methods, and the potential of hydrochar as an adsorbent to remove NH₄⁺-N and PO₄^3--P from wastewater. The results showed that acetic acid or sodium hydroxide assisted HTC and activation with magnesium chloride or air could improve the surface properties of hydrochar. Acetic acid modification generated extensive oxygenated functional groups, while sodium hydroxide modification produced hydrochar with a high N/C ratio and surface aromaticity. Treating hydrochar with magnesium chloride could impregnate nano-magnesium particles on the hydrochar, thereby improving the ability to remove N and P. Air activation of hydrochar resulted in more oxygen containing functional groups. The NH₄⁺-N and PO₄^3--P adsorption capacities of these hydrochars ranged from 92.6 to 122.4mg/g and 1.6 to 15.8mg/g, respectively. The adsorption capacity of hydrochars in swine wastewater is similar to the results of artificial wastewater. The results suggested that Mg-nanoparticle dispersion and oxygen-containing functional groups played a major role in adsorption than ion exchange and physisorption.

Review of Typha spp. (cattails) as toxicity test species for the risk assessment of environmental contaminants on emergent macrophytes

Macrophytes play an important role in aquatic ecosystems, and thus are often used in ecological risk assessments of potentially deleterious anthropogenic substances. Risk assessments for macrophyte populations or communities are commonly based on inferences drawn from standardized toxicity tests conducted on floating non-rooted Lemna species, or submerged-rooted Myriophyllum species. These tests follow strict guidelines to produce reliable and robust results with legal credibility for environmental regulations. However, results and inferences from these tests may not be transferrable to emergent macrophytes due to their different morphology and physiology. Emergent macrophytes of the genus Typha L. are increasingly used for assessing phytotoxic effects of environmental stressors, although standardized testing protocols have not yet been developed for this genus. In this review we present a synthesis of previous toxicity studies with Typha, based on which we evaluate the potential to develop standard toxicity tests for Typha spp. with seven selection criteria: ecological relevance to the ecosystem; suitability for different exposure pathways; availability of plant material; ease of cultivation; uniform growth; appropriate and easily measurable toxicity endpoints; and sensitivity toward contaminants. Typha meets criteria 1-3 fully, criteria 4 and 5 partly based on current limited data, and we identify knowledge gaps that limit evaluation of the remaining two criteria. We provide suggestions for addressing these gaps, and we summarize the experimental design of ecotoxicology studies that have used Typha. We conclude that Typha spp. can serve as future standard test species for ecological risk assessments of contaminants to emergent macrophytes.

Efficacy and Nontarget Effects of a Spinosad-Based Larvicide in Minnesota Vernal Pools and Cattail Marshes

Larvicides that contain spinosad, a bacterial metabolite, are used to control mosquitoes in diverse aquatic habitats. These same habitats are home to other invertebrates, including Crustacea-fairy shrimp, isopods, and amphipods-and mollusks-fingernail clams and freshwater snails. A double-blind study evaluated the effects of Natular® G, a granular treatment containing spinosad, on spring Aedes spp. and nontarget invertebrates in vernal wetlands. Within 14 days after application, Natular G controlled larvae of spring Aedes by 53-84%, depending on species, but had no significant effects on numbers of fairy shrimp, fingernail clams, or freshwater snails. A second double-blind study evaluated effects on Coquillettidia perturbans and nontarget isopods and amphipods in cattail marshes. Treatment reduced emergence of Cq. perturbans by 25% but did not change numbers of isopods or amphipods. The 2 experiments indicate Natular G could be effective against spring Aedes in vernal wetlands, less so against Cq. perturbans in cattail marshes, and yet pose minimal risk to crustaceans and mollusks in either vernal wetlands or cattail marshes.

Phytoextraction of ciprofloxacin and sulfamethoxaxole by cattail and switchgrass

Cattail (Typha latifolia L.) and switchgrass (Panicum virgatum L.) can effectively remove inorganic contaminants from soils and biosolids, but their role in the attenuation of organic contaminants, such as antimicrobials, is currently poorly understood. Uptake by plants is one of several mechanisms by which plant-assisted attenuation of antimicrobials can be achieved. The objectives of this growth room study were to evaluate the plant uptake of ciprofloxacin (CIP) and sulfamethoxazole (SMX) and examine their partitioning between plant roots and aboveground biomass (AGB). Plant uptake of the two ¹⁴C labeled antimicrobials was studied at two environmentally relevant concentrations (5 and 10 μg L^-1). Plants were destructively sampled every 3-4 d during the 21-d growth period. Accumulation of CIP and SMX in both plant species was greater in the roots than in the AGB. The percentage uptake values of the two antimicrobials were significantly greater for cattail (34% for CIP, 20% for SMX) than for switchgrass (10% for both CIP and SMX). Translocation factors of the two antimicrobials were <1 for both plants, indicating slow movement of the antimicrobials from the roots to the shoots. For cattail roots, the BCF for CIP (1.58 L g^-1) was significantly greater than that for SMX (0.8 L g^-1). By comparison, BCFs for switchgrass roots did not differ significantly between CIP (0.88 L g^-1) and SMX (1.13 L g^-1). These results indicate greater potential for cattail to phytoextract CIP and SMX and significantly contribute to the attenuation of these antimicrobials in systems designed for the phytoremediation of contaminated wastewater.

Selenium speciation and bioavailability from mine discharge to the environment: a field study in Northern Quebec, Canada

The speciation, behaviour, and bioavailability of released selenium (Se) from mine effluent discharge to sediments and plants were assessed. Discharged mine effluent containing 65±0.9 μg/L of total Se subsequently contaminated the exposed sediment with an average total Se concentration of 321 mg/kg as well as exposed Typha latifolia plants where 534 and 92 mg/kg were found in roots and leaves, respectively. The strategy of T. latifolia in Se phytoremediation consisted of a phytostabilization and accumulation of Se predominantly in roots. Se plant root uptake was promoted by synergistic effects of Cu, Pb, Zn, and Cd while Co, Fe, Mn, Ni, Na, K, and Mg had antagonistic effects. Se plant uptake was also governed by sediment characteristics mainly pH, total Se, and iron concentration. Se speciation results demonstrated that the most accumulated Se species by T. latifolia roots were selenite and selenomethionine with average concentrations of 2.68 and 2.04 mg/kg respectively while other Se species were the most translocated (average translocation factor of 1.89). Se speciation in roots was positively correlated with sediment pH, organic matter, electrical conductivity, and iron concentration. This study confirms deploying corrective measures for mine effluent treatment before discharge in a sediment-plant environment to protect living organisms from toxic effects. T. latifolia is recommended as a Se-hyperaccumulator to be used for mine soil phytoremediation in cold regions in Canada.

Nutrient recovery from the digestate obtained by rumen fluid enhanced anaerobic co-digestion of sewage sludge and cattail: Precipitation by MgCl2 and ion exchange using zeolite

The aim of this study was to recover nutrients (NPK and other) from the liquid fraction of digestate obtained by rumen fluid enhanced anaerobic co-digestion of sewage sludge and cattail (Typha latifolia grass). Firstly, anaerobic digestion (AD) studies were performed to examine the biogas potential of selected substrates. The liquid fraction of digestate was then used in nutrient recovery experiments. Four methods were applied to recover nutrients: i) conventional struvite precipitation by MgCl₂, ii) simultaneous precipitation and ion exchange by Na-zeolite, and iii) two-step recovery using precipitation, followed by ion exchange with powdered or iv) granulated Na-zeolite. The products of nutrient recovery were characterised using different chemical methods and the cress seed germination test was performed to evaluate their fertility potential. The results show that co-digestion of sewage sludge with cattail enhanced biogas production by almost 50 vol%. The addition of rumen fluid positively contributed to the degradation of lignocellulosic materials and to biogas production. In all of the recovery methods tested, phosphorus was successfully recovered with efficiency of more than 99 wt%. Nitrogen recovery was less efficient than phosphorus recovery, 85-92 wt%. Simultaneous precipitation and ion exchange lowered nitrogen recovery efficiency compared to classical struvite precipitation, while sequential precipitation and ion exchange resulted in improvement. The most efficient method was two-step recovery using granulated zeolite. The precipitates consisted of different Mg and K-phosphates in quite irregular shapes. The struvite and K-struvite were detected in low quantities. The precipitates contained more than 25 wt% of macronutrients (NPK), exhibited effective utilization of nutrients by plants, and showed good fertility potential. Precipitate mixed with powdered Na-zeolite promises to be interesting for further agricultural use, as zeolite offers several potential improvements for soil. Both zeolites exhibited good performance in the recovery of K⁺ ions.

Aerenchyma, gas diffusion, and catalase activity in Typha domingensis: a complementary model for radial oxygen loss

Radial oxygen loss is a physical phenomenon that occurs naturally in aquatic plants. Typha domingensis was chosen as a model plant because it possesses basic morphological characteristics, such as a stem (rhizome) that produces leaves and adventitious roots, which are present in many aquatic plants. This study aimed to evaluate the following: the relevance of the anatomy of T. domingensis on gas diffusion among organs; the influence of plant parts on radial oxygen loss; the role of catalase in radial oxygen loss; and the proposition of a novel explanation for the downward diffusion of oxygen through the organs of this aquatic macrophyte and into the environment. Typha domingensis plants were cultivated in a greenhouse under different conditions: plants with intact leaves, plants with leaves cut in half, and plants without leaves. Furthermore, we evaluated the percentage of aerenchyma in different vegetative organs, the minimum pressure required for radial oxygen loss, the daily variations of dissolved oxygen, and the roots' catalase activity. The results demonstrated that certain cellular features contributed to decreased oxygen diffusion among the organs, specifically, those found in the leaf-rhizome and root-rhizome interfaces as well as the suberin and lignin layers in these regions. Additionally, our experiments with a catalase activator and inhibitor validated that a significant amount of the oxygen released in radial oxygen loss could not, in fact, be exclusively supplied by the atmosphere. Thus, a complementary model is proposed in which catalase activity is an important component of radial oxygen loss.

Macrophyte and indigenous bacterial co-remediation process for pentachlorophenol removal from wastewater

This study has contributed in the description of bioaugmentation-phytoremediation efficiency process using Typha angustifolia concerning PCP tolerance and removal from wastewater. Samples of wastewater were collected from industrial wastewater plants, namely row wastewater effluent "E.WW", primary wastewater "P.WW", secondary wastewater "S.WW", clarified wastewater "AC.WW". These effluents were spiked with PCP at different rate (100, 500, and 1000 mg.L^-1), physical, chemical and biological properties were monitored. A second experiment was set up in order to check the efficiency of phytoremediation treatments of the different effluents artificially contaminated with 200 mg.L^-1 PCP after 20 days lab scale experiment. An important PCP removal by indigenous bacteria was showed in S. WW with values from 1000 to 72.2 mg.L^-1 from T0 (start of the experiment) to TF (end of the experiment), respectively. Phytoremediation process allowed a decrease of PCP rate from 200 to 6.4 mg.L^-1, a decrease of chloride content from 14.0 to 4.0 mg.L^-1 in S.WW samples was observed. Furthermore, a significant increase of bacterial number in S.WW and AC.WW to 1.700 × 10⁶ and 1.450 × 10⁶ CFU.mL^-1, respectively was observed. In addition, the DGGE analysis showed that after bioaugmentation-phytoremediation treatments, the highest species richness and relative abundance in wastewater effluent was observed. Novelty statement Pentachlorophenol (PCP) is one of highly toxic of polychlorophenols and required to continuously monitor in environment. This paper presenting a sensitive method phytoremediation and bioaugmentation for PCP biotransformation in wastewater. The novelty is the choice of a macrophyte Typha angustifolia, which is still used for the elimination of heavy metals but it not used for pesticide and pollutant removal in wastewater. Also, there are different analysis that was performed in order to check phyto-technique process (DGGE and HPLC). On the other side, in this study, the phyto-techniques with Typha angustifolia positively affected intrinsic microorganisms in order to promote pollutant remediation. So, the intrinsic microorganisms in wastewater with the macrophyte presence have a great capacity to reduce this pollutant and improve the bioremediation process.

Cr, Ni, and Zn removal from landfill leachate using vertical flow wetlands planted with Typha domingensis and Canna indica

Chromium (Cr), Nickel (Ni), and zinc (Zn) removal from landfill leachate using mesocosm-scale vertical flow wetlands, the effect of recirculation, and the ability of macrophytes to retain metals were evaluated. Wetlands were filled with coarse sand and light expanded clay aggregates and planted with Typha domingensis or Canna indica. Wetlands were operated using intermittent loading, with and without recirculation. Raw leachate was diluted and spiked with metals to reach the following concentrations: 0.2 mg L^-1 Cr , 0.2 mg L^-1 Ni, and0.2 mg L^-1 Zn and 1.0 mg L^-1 Cr, 1.0 mg L^-1 Ni, and 1.0 mg L^-1 Zn. Wetlands planted with T. domingensis presented higher metal removal than those planted with C. indica. Recirculation enhanced metal removal efficiencies significantly, being for T. domingensis/C. indica: 60/54, 49/47, 61/47% for Cr, Ni, and Zn at 0.2 mg L^-1, and 80/71, 76/62, 73/59% for Cr, Ni, and Zn at 1.0 mg L^-1, respectively. Metals were efficiently retained by macrophytes. Plant biomass and metal concentrations in roots were significantly higher than in shoots. Scanning electron microscopy and X-ray microanalysis showed that metals were absorbed by internal root tissues. A hybrid wetland planted with T. domingensis may be implemented to improve not only metal but also chemical oxygen demand and total nitrogen removals.

Microbial abundance and community in constructed wetlands planted with Phragmites australis and Typha orientalis in winter

The microbial abundance and communities were characterized in CWs with different plant species during winter. Better removal efficiency with high microbial abundance and diversified microbial community were found in CWs planted with Phragmites australis. This study confirmed that in winter, withered plants in CWs can effectively remove NH₄⁺-N and COD by affecting microbial abundance and community structure.

Evaluation of VEGF mediated pro-angiogenic and hemostatic effects and chemical marker investigation for Typhae Pollen and its processed product

ETHNOPHARMACOLOGICAL RELEVANCE

Typhae Pollen (TP) is a well-known Traditional Chinese Medicine (TCM) to remove blood stasis. Carbonized Typhae Pollen (CTP), a processed product of TP after being stir-fried, has been widely applied to clinical practice with its capability of hemostasis. However, the underlying mechanism of TP and CTP are still not fully elucidated and discrimination against TP and CTP remains a challenge.

AIM OF STUDY

The aim of this study is to investigate whether TP could remove blood stasis by promoting angiogenesis and the process of carbonizing it could enhance hemostatic effect. Meanwhile, some chemical markers for quality control of CTP had better to be found.

MATERIAL AND METHODS

The changes of constituents between TP and CTP were analyzed by UPLC-QTOF-MS/MS. We investigated pro-angiogenic and hemostatic effects of TP and CTP in two zebrafish models: VRI-induced ISV insufficiency model and Ator-induced cerebral hemorrhage model. Subsequently, quantitative real-time PCR (qRT-PCR) was applied to investigate the mechanism of pharmacological effects. Finally, chemometric method was applied to find chemical markers.

RESULTS

A total of 19 compounds were identified in qualitative analysis. The loss rate of each compound was calculated and compared. Two compounds (huaicarbon A/B) could only be detected in CTP and the content of flavonoid glycosides in CTP was significantly decreased compared with TP. The average content of the three identified flavonoid aglycones (quercetin, isorhamnetin and kaempferol) was increased about 30 percent in CTP. TP promoted pro-angiogenesis by up-regulating the expression of VEGFA, flt1 and kdr. After heating process, the pro-angiogenic activity was reduced and hemostatic activity was enhanced in CTP. Then qRT-PCR analysis found that CTP could significantly up-regulate the expression of VEGFA and vWF. In the discovery of markers, 6 chemical markers for discrimination of TP and CTP were obtained by chemometric method.

CONCLUSION

Our research indicated that the pro-angiogenic activity of TP was involved in VEGF signaling pathway. After processing, hemostatic activity of CTP has been enhanced by up-regulating the expression of VEGFA and vWF. A chemical marker database was established to provide a scientific evidence for quality control, mechanism and the clinical application of TP and CTP.

Root growth and nutrient removal of Typha domingensis and Schoenoplectus californicus over the period of plant establishment in a constructed floating wetland

Constructed floating wetlands have been employed worldwide to treat effluents and to ameliorate water quality of water resources. However, the period of macrophyte establishment into the hydroponic functioning has not been specifically addressed. This paper reports root growth and nutrient removal of Typha domingensis and Schoenoplectus californicus in a floating structure without growth substrates over the period of 11 weeks of macrophyte establishment. The experiment was conducted in mesocosm with two replicas of each specie. Weekly batches were applied with three different concentrations of a synthetic effluent. Root growth was measured to evaluate the macrophyte adaptation. Physicochemical parameters were weekly monitored, and total nitrogen, nitrate, total phosphorus, and orthophosphate were quantified to assess nutrient removal. Both species have adapted to the floating structure, but T. domingensis presented superior root growth in relation to S. californicus. No significant differences were found during the application of first two synthetic solutions. As to solution 3, significant differences between input and output values were found to total phosphorus (F = 9.948, df = 1, p = 0.008), nitrate (F = 5.990, df = 1, p = 0.031), and total nitrogen (F = 40.212, df = 1, p < 0.0001). Removal efficiency of T. domingensis ranged from 4 to 31% for total nitrogen and from 8 to 15% for total phosphorus. S. californicus, on the other hand, varied its removal efficiency from - 6 to 5% and 2 to 12% for total nitrogen and total phosphorus, respectively. Time period of macrophyte establishment varied between species, and it was an important factor that contributed to the increase of nutrient removal rates and root growth.

Plant species for floating treatment wetlands: A decade of experiments in North Italy

Floating treatment wetlands (FTWs) represent a recent system within the family of surface flow wetlands, able to directly treat various types of wastewaters in natural or artificial water bodies. In these conditions, traditional non-floating macrophytes, installed in self-buoyant mats, hydroponically expand their root systems in the wastewater, interacting with a rich microbial biodiversity and thereby removing different pollutants. This study aimed to evaluate the growth performances of 5 plant species installed in different FTWs after ten years of research conducted in North Italy: Phragmites australis, Iris pseudacorus, Typha latifolia, Carex spp. and Lythrum salicaria. During the entire experimental period, above-mat biomass production varied from 46.7 g m^-2 (L. salicaria) to 1466.0 g m^-2 (T. latifolia), whereas below-mat biomass production ranged between 205.7 g m^-2 (L. salicaria) and 4331.1 g m^-2 (P. australis). Both shoot height and root length assumed the highest values for T. latifolia (189.0 cm and 59.3 cm, respectively), the lowest for L. salicaria (42.3 cm and 35.1 cm, respectively). All plant species increased both above- and below-mat biomass productions over consecutive growing seasons through horizontal colonization of the floating mats, although not always significantly. Moreover, the growth of I. pseudacorus, P. australis and T. latifolia was significantly influenced by wastewater physico-chemical composition, exhibiting species-specific behavior. In general, all species showed a good aptitude to survive in hydroponic conditions both during the growing season and the winter, even though in a few cases the survival of I. pseudacorus and P. australis was strongly reduced by alien predators (Myocastor coypus) that badly damaged plant aerial tissues.