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Invasive Phragmites australis australis is invading and homogenizing Great Lakes coastal wetlands at an alarming rate. Phragmites australis is thought to reduce wetland biodiversity both directly and indirectly through the acquisition of resources and alteration of habitat. Restoration efforts to manually remove approximately 10,000 m2 of P. australis from Point Pelee National Park began in 2020 and here, we assess the effect of manual cut and burn P. australis removal on emergent aquatic vegetation communities. By using systematic transects stratified across water depth and wetland composition we compared emergent vegetation communities among a P. australis-invaded wetland, a P. australis-treated wetland, and a non-invaded wetland. We found that 2 years post-restoration, vegetation species richness and the prevalence of non-P. australis vegetation were greater in the treated and non-invaded wetlands than the invaded wetland. More specifically, we found almost twofold more plant species in the treated and non-invaded wetland compared to the invaded wetland, with only seven plant species found within the invaded wetland. Analysis of similarity and non-metrical multi-dimensional scaling analysis revealed that the vegetation community of the treated wetland resembled the vegetation community of the non-invaded wetland, and the vegetation community of the invaded wetland was very different from both the treated and non-invaded wetlands. Manual removal of P. australis is time-consuming and labour-intensive, however; these findings confirm that small-scale manual removal of P. australis can result in the return to native plant assemblages in coastal wetlands two years after treatment. [ABSTRACT FROM AUTHOR]

Water level variations (WLVs) substantially affect the spatial distribution of riparian vegetation. Accurately quantifying the water level fluctuation requirements (WLFRs) of aquatic macrophytes is essential for effective ecological water level management. Nevertheless, studies on the WLFRs of herbaceous plants in large river floodplains, such as Phragmites australis (common reed) and Phalaris arundinacea (reed canarygrass), are limited. Herein, we investigated the WLFRs of the two plants across water bodies with different WLVs in the Yangtze River Basin. We focused on the effects of sub-monthly and sub-daily WLVs on their average monthly water depth requirements (WDRs) during critical growth periods. Our findings indicated: (1) For Phragmites, during the emergence period, the upper limits of WDRs decreased with increased amplitudes of sub-monthly WLVs and with greater frequency and amplitude of sub-daily WLVs, in which sub-daily variations had a more pronounced effect. Conversely, during the rapid growth period, the upper limits increased with larger sub-monthly WLVs amplitudes, but decreased with higher frequency and amplitude of sub-daily WLVs. (2) For Phalaris, during both the emergence and rapid growth periods, intensified sub-daily WLVs led to decreased upper limits of WDRs. In summary, although distinct disparities existed in the WLFRs of Phragmites and Phalaris across various water bodies, the trends in WDRs during the emergence and rapid growth periods were consistent for both species. These findings provide essential quantitative data to restore aquatic vegetation and carry out effective ecological water level management in large-scale riparian ecosystems. [ABSTRACT FROM AUTHOR]

Seedling recruitment is an important mode of establishment utilized by many invasive plants. In widespread invasive plants, regional variation in the rates of seedling recruitment can contribute to differences in invasion intensity across regions. In this study, we examined regional variation in reproductive traits and seedling performance in a cosmopolitan invasive wetland grass, Phragmites australis. We tested whether nitrogen levels and regions with different histories and intensities of invasion would affect reproductive traits and seedling performance. We sampled invasive Phragmites inflorescences from 34 populations across three regions in North America: The Northeast (old, most intense invasion), the Midwest (recent, intense invasion), and Southeast (recent, sparse invasion). We hypothesized that Northeast Phragmites populations would have the highest reproductive output and seedling performance, and that populations experiencing high nitrogen pollution would have higher reproductive output and seedling performance under high nitrogen conditions. We found that populations in the Northeast had the highest inflorescence mass, as expected. We also found that despite sparse distribution of Phragmites in the Southeast, populations from the Southeast displayed a high potential for sexual reproduction. However, increasing watershed-level nitrogen (kg/km2) decreased percent seed germination in Southeastern populations, suggesting that Southeastern populations are sensitive to rising nitrogen levels. While elevated nitrogen improved seedling performance through increased belowground growth in Southeastern Phragmites seedlings, elevated nitrogen decreased belowground growth in Midwestern seedlings. These results suggest that the southeastern region of North America may be primed to become an emergent invasion front of Phragmites, warranting more research into the possible management of Phragmites spread in the region. [ABSTRACT FROM AUTHOR]

In the last decade, microplastics (MPs) have become a significant environmental pollutant with potential negative effects on aquatic biodiversity and ecosystems. This mesocosm study examined the effect of MPs on the growth and physiology of two common aquatic macrophytes (Myriophyllum spicatum and Phragmites australis), focusing on changes in biomass allocation and nutrient contents. We evaluated oxidative stress responses by measuring superoxide dismutase, malondialdehyde, soluble sugars, free amino acids, and glutamate synthetase activities for M. spicatum, and we assessed photosynthetic processes through metrics including Fv/Fm, electron transfer rate, and Y(II) for P. australis. Unlike most previous studies in plants, we found that the growth and all functional traits of these two plants were not significantly affected by the common MP type (polyethylene) at either low or high concentrations. Additionally, we have examined the impact of another type of MP (polystyrene) on P. australis, and no significant effect was observed. In conjunction with prior case studies, the majority of which demonstrated the toxic impacts of MPs, our research indicates that plants exhibit a species-specific response to MPs. In addition to the strong adaptation of widespread plants used in this study, the large experimental system and relative long-term treatment may also explain our negative results. Our study highlights the need to further investigate species-specific tolerances and adaptive responses to MPs to better understand their ecological impacts. [ABSTRACT FROM AUTHOR]

Heavy metal contamination is a serious global issue that threatens both environmental and human health. This study investigated the levels of 12 heavy metals in sediments, roots, stems, and leaves of Phragmites australis (common reed) from a river in Iran, using an inductively coupled plasma optical emission spectrometer (ICP-OES). The sediment metal concentration order was: Aluminum (Al) > Iron (Fe) > Manganese (Mn) > Zinc (Zn) > Magnesium (Mg) > Nickel (Ni) > Chromium (Cr) > Lead (Pb) > Copper (Cu) > Arsenic (As) > Vanadium (V) with Cadmium (Cd) below detection limit. Concentrations of As, Ni, Pb, and Zn in the sediments exceeded background values. According to sediment quality guidelines (SQGs), metal concentrations were between the threshold effect level (TEL) and the probable effect level (PEL), remaining below the severe effect level (SEL), except for Ni. Average metal concentrations in plant tissues were lower than in sediment samples, with roots showing higher levels of Cd, V, Cu, Pb, Zn, As, Al, Mg, and Fe than in the shoots, while leaves had higher Ni, Cr, and Mn. The bioaccumulation factor of less than 1 (except for V) indicates limited bioavailibility of these metals. [ABSTRACT FROM AUTHOR]

Eutrophication resulting from anthropogenic activities has been recognized as a significant driver of changes in ecosystem functioning. Furthermore, it may exacerbate the top-down effect and thus exert an important impact on plant growth. To test this hypothesis, we conducted a 3-year manipulative field experiment to investigate the impacts of nitrogen addition and crab herbivory on the growth of Phragmites australis in the salt marsh of the Yellow River Delta. The results demonstrated that a 3-year nitrogen addition can significantly increase the total nitrogen and carbon content of P. australis leaves, thereby enhancing their nutritional value and palatability, as well as increasing the proportion of leaves consumed by crabs. Therefore, nitrogen addition together with crab herbivory had a significant negative effect on P. australis height, leaf length, and leaf breadth in the ambient crab and procedural crab cage treatment compared to the crab exclusion treatment. The structural equation modeling further substantiated these findings. Themodel revealed a direct and positive correlation between nitrogen addition and leaf nutrient content (path coefficient = 0.34). Additionally, it demonstrated a direct and positive relationship between leaf nutrient content and the proportion of leaves consumed by crabs (path coefficient = 0.22). Simultaneously, there was an observed negative correlation (path coefficient = - 0.37) between the proportion of leaves consumed by crabs and plant functional traits, represented by leaf length in the model, during 2018. Moreover, the crab exclusion treatment significantly reduced the proportion of leaves consumed by crabs and thus enhanced the P. australis individuals, leaf number, and biomass. Overall, crab herbivory had a significant detrimental top-down effect on the growth of P. australis, and nitrogen enrichmentmay exacerbate this top-down effect. The findings of our study highlight the combined adverse effects of nutrient enrichment and top-down on plant functional traits and plant growth. The findings of this study will contribute to a comprehensive understanding of the underlying factors influencing vegetation degradation in coastal wetland, thereby establishing a solid theoretical framework for the conservation and management of wetland ecosystems within the context of global environmental change. [ABSTRACT FROM AUTHOR]

Aim: Estuarine vegetation routinely experiences natural tidal fluctuations and is highly vulnerable to extreme events such as heavy rainfall, leading to changes in plant population structure and adaptability. Genetic and epigenetic modifications are widely considered to be mechanisms of phenotypic variation, triggered in plants responding to extreme changing environments. However, understanding on correlations among genetic, epigenetic, and phenotypic variation of wild plant populations is still limited. Location: China. Methods: In this study, populations of the typical wetland clonal species Phragmites australis were selected from four estuaries along various latitudes in China. Genetic and epigenetic diversity and phenotypic variation of these populations were analysed. Results: Phenotypic variation of P. australis populations was the highest at Yellow River Estuary and the lowest at Min River Estuary. Across all estuaries, Genetic and epigenetic diversity was strongly linear‐correlated. Genetic diversity had significant correlations with variation in reproductive traits, whereas epigenetic diversity had significant correlations with variation in growth traits. Climatic factors of mean annual temperature and precipitation, as well as soil nitrogen and phosphorus, were negatively correlated with variation in genetic diversity, epigenetic diversity, and variation in reproductive traits of P. australis populations along latitudes. Variation in growth traits was negatively correlated with soil salinity, reflecting the limiting effect of salinity on plant growth. Main Conclusion: Our findings found that genetic and epigenetic variations may play different roles in phenotypic variation of P. australis populations along latitudes, the variation becomes greater when the climatic and edaphic conditions deteriorate. The findings shed new light on the adaptation and evolution of wetland plant populations along a large latitudinal scale, and may contribute to the revegetation of estuary wetlands. [ABSTRACT FROM AUTHOR]

From tannery effluent (TE) severely polluted with heavy metals (HMs viz., Cr, Cu, Cd, and Pb), hydrophytic phytoextraction remains a challenge as transplanted plants succumb to death on facing acclimatization shock. Current study was aimed at diluting TE with harvested rainwater (HR) for improving HM phytoextraction potential of Phragmites australis (a hydrophyte) assisted with phycoremediation of coupled algae (viz., Oedogonium sp. and Pithophora sp.). The TE:HR dilutions (TEDs) 0, 25, 50, 75, and 100% (v/v) included three sets: set-1 included algae only, set-2 included P. australis only and set-3 included P. australis coupled with combined algal inoculum. Results showed that P. australis assisted with HR dilution and combined algal inoculum showed significantly greater uptake of HMs from each of the TEDs than respective control treatments. Combined algal application in the TEDs proved phycoremediation assistants based on their bioaccumulation factor (BF). The dry biomass of P. australis in TEDs applied with phycoremediation assistants remained greater than uninoculated ones. Overall, HM translocation factor (TF) of P. australis for Cr, Cu, Cd, and Pb remained ≥ 1. The study concludes that HM phytoextraction is substantially increased when concentrated TE is diluted with HR and assisted with phycoremediation of HM tolerant algae. [ABSTRACT FROM AUTHOR]

Escape from native range enemies can give invasive species a competitive edge according to the enemy‐release hypothesis. While more commonly associated with predators and herbivores, release from belowground microbial antagonists has been recently demonstrated to benefit invasive plants. Biogeographic variation in dominance and comparisons of soil communities suggest that invasive European Phragmites australis may have also benefitted from belowground enemy release in North America (NA). Here we examine the effects of native range (Europe) versus introduced range (NA) soil communities on European and North American P. australis using a reciprocal inoculation seedling growth experiment. Contrary to the enemy‐release hypothesis, we found that North American P. australis was sensitive to soil community origin in that the seedlings grown in European soil communities had higher total biomass than seedlings grown in North American soil communities. This pattern was not observed in the European P. australis seedlings which had similar biomass when grown with North American or European soil communities. Notably, North American P. australis had higher biomass than European P. australis regardless of which soil community it was grown in, suggesting a growth–defense tradeoff. Though the relative abundance of mutualists and pathogens composition did not differ between the two ranges, an indicator analysis revealed that mutualistic fungi and bacteria were key components of European soil communities but not in North American communities. Interestingly, North American soil communities had lower β diversity than European communities suggesting higher levels of community conservation among North American populations. This research represents the first evidence of growth–defense trade‐offs in North American P. australis and offers a novel mechanism in understanding the invasion of P. australis in NA. [ABSTRACT FROM AUTHOR]

Phragmites australis is a common helophyte, covering much of the sheltered and shallow soft bottoms along the coasts of the Baltic Sea. Despite the expansion of P. australis over the past decades, there is little information on aquatic macroinvertebrates within P. australis beds. In this study, we examined the effect of large-scale (wave exposure, nutrients) and small-scale (distance from the seaward edge, live and dead stalk density, epiphyte and rhizome biomass) drivers on the density, taxa richness, diversity, and community structure of epifauna and infauna in monospecific P. australis beds around the Åland Islands and the Archipelago Sea. We found that higher wave exposure and nutrient levels generally supported higher epi- and infauna abundance and taxa richness. The effects on Shannon–Wiener diversity were less evident apart from an increase of the infauna diversity in the Archipelago Sea with increasing nutrient levels. On a local scale, the distance from the seaward edge, live and dead stalk density, and epiphyte biomass had varying effects on both epi- and infauna communities in the different regions. Rhizome biomass had no effect on either the epi- or infauna abundance, taxa richness, or diversity. Furthermore, according to existing studies, other habitats, e.g., Zostera marina meadows, Fucus vesiculosus belts, and vegetated soft-bottomed shallow bays, are generally characterized by more abundant fauna, except for the infauna, which had a higher density in P. australis beds than in vegetated soft-bottomed shallow bays. P. australis are a widespread, expanding, and understudied habitat with an important role in supporting coastal biodiversity. [ABSTRACT FROM AUTHOR]

A novel mesoporous magnetic biochar (MBC) was prepared, using a randomly growing plant, i.e., common reed, as an exporter of carbon, and applied for removal of methylene blue (MB) from aqueous solutions. The prepared sorbent was characterized by nitrogen adsorption/desorption isotherm, saturation magnetization, pH of point of zero charges (pHPZC), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The obtained MBC has a specific surface area of 94.2 m2 g−1 and a pore radius of 4.1 nm, a pore volume of 0.252 cm3 g−1, a saturation magnetization of 0.786 emu g−1, and a pHPZC of 6.2. Batch adsorption experiments were used to study the impact of the physicochemical factors involved in the adsorption process. The findings revealed that MB removal by MBC was achieved optimally at pH 8.0, sorbent dosage of 1.0 g L−1, and contact time of 30 min. At these conditions, the maximum adsorption was 353.4 mg g−1. Furthermore, the adsorption isotherm indicated that the Langmuir pattern matched well with the experimental data, compared to the Freindlich model. The ∆G was − 6.7, − 7.1, and − 7.5 kJ mol−1, at 298, 308, and 318 K, respectively, indicating a spontaneous process. The values of ∆H and ∆S were 5.71 kJ mol−1 and 41.6 J mol−1 K−1, respectively, suggesting endothermic and the interaction between MB and MBC is van der Waals type. The absorbent was regenerated and reused for four cycles after elution with 0.1 mol L−1 of HCl. This study concluded that the magnetic biochar generated from common reed has tremendous promise in the practical use of removing MB from wastewater. [ABSTRACT FROM AUTHOR]

We present a genome assembly from an individual Phragmites australis (the common reed; Streptophyta; Magnoliopsida; Poales; Poaceae). The genome sequence has a total length of 848.70 megabases. Most of the assembly is scaffolded into 24 chromosomal pseudomolecules, supporting the specimen being an allotetraploid (2n = 4x = 48). The three mitochondrial assemblies had lengths of 304.58, 92.24, and 76.54 kilobases and the plastid genome assembly had a length of 137.67 kilobases. Gene annotation of this assembly on Ensembl identified 47,513 protein-coding genes.

In this study, the wastewater analyses of Oued K'sob for one year showed a spatiotemporal diminution of zinc content seasonally, it rest light than copper. But Zinc and copper a threat to the environment of the region. The wastewater analyses of Oued K'sob water for one year showed a spatiotemporal diminution of zinc content seasonally, with a minimum and maximum range of 249 ± 219 µg/l and 2382 ± 3426 µg/l obtained in autumn and summer for the zinc and 75 ± 24 µg/l and 433 ± 310 µg/l obtained in winter and spring at the first and fifth station for the copper. These concentrations of zinc and copper a threat to the environment of the region. Like a solution for this problem, the absorption, accumulation and translocation abilities of Phragmites australis were determined toward iron (Fe), copper (Cu), zinc (Zn) and lead (Pb). In the soils contaminated by different concentrations (100, 200 and 500 mg/L), the absorption, accumulation and transport ability of elements were evaluated via the Bio-concentration (BCF), Bioaccumulation (BF) and Translocation (TF) factors. A proportional increase between the BCF, BFs, TFs and the irrigation concentrations, where BCFs of all metallic elements exceed 1 and the Zn BCF, BFs and TFL are the highest and exceed 1 relative to the other elements which remain lower than 1, which has a low accumulation. Therefore, according to the BCFs obtained and which exceed 1, we can consider this plant as a hyper-accumulator of Zn, Fe, Cu and Pb. Extraction of fatty and organic acids followed by HPLC confirmed the oxalic, citric, malic, succinic, fumaric, formic, acetic, propionic, and butyric acid presence, which are responsible for the transport of the metal from roots to leaves. In the light of these results, we can therefore propose Phragmites australis species as an alternative and natural solution to reduce the high concentrations of zinc and copper in the Oued k'sob (region of Bordj Bou Arreridj, Algeria). The main objective of this study was to carry out and determine the phyto-remedial effect of Phragmites australis species in pots from artificial contaminated soils in order to classify this plant as an accumulator or hyper-accumulator of metals, in particular against zinc, iron, copper and lead in order to reduce their toxicities in the environment through decontamination and/or protection of the ecosystems (soil and water); and why not use this bioremediation system via this species during wastewater treatment at wastewater treatment plants to increase the quality of treatment of one side and reduce the cost on the other side. [ABSTRACT FROM AUTHOR]

Abstract Escape from native range enemies can give invasive species a competitive edge according to the enemy‐release hypothesis. While more commonly associated with predators and herbivores, release from belowground microbial antagonists has been recently demonstrated to benefit invasive plants. Biogeographic variation in dominance and comparisons of soil communities suggest that invasive European Phragmites australis may have also benefitted from belowground enemy release in North America (NA). Here we examine the effects of native range (Europe) versus introduced range (NA) soil communities on European and North American P. australis using a reciprocal inoculation seedling growth experiment. Contrary to the enemy‐release hypothesis, we found that North American P. australis was sensitive to soil community origin in that the seedlings grown in European soil communities had higher total biomass than seedlings grown in North American soil communities. This pattern was not observed in the European P. australis seedlings which had similar biomass when grown with North American or European soil communities. Notably, North American P. australis had higher biomass than European P. australis regardless of which soil community it was grown in, suggesting a growth–defense tradeoff. Though the relative abundance of mutualists and pathogens composition did not differ between the two ranges, an indicator analysis revealed that mutualistic fungi and bacteria were key components of European soil communities but not in North American communities. Interestingly, North American soil communities had lower β diversity than European communities suggesting higher levels of community conservation among North American populations. This research represents the first evidence of growth–defense trade‐offs in North American P. australis and offers a novel mechanism in understanding the invasion of P. australis in NA.

This article describes salt distribution (Ca2+, Mg2+, K+, Na+) in halophytic plants, common reed (Phragmites australis) taken from four locations in Ostrava - Důl Lazy, Karvinský potok, Heřmanický rybník, Nový rybník. The research aimed to find out where salts, but also other elements acting as contaminants in the environment are stored, how they are distributed, what physiognomic changes they cause in the plant, and to what extent common reed can face the stress conditions of salinity in the phytoremediation process. The experiment took place under controllable conditions in the phytotron - temperature 25 °C, light regime 12 hours day/12 hours night, air humidity 60 %, light intensity 150 µmol.m-2.s-1. Bunches of reeds were subjected to gradual salinization with 1% to 5% Darkov salt solutions. Biomass samples were analyzed by instrumental neutron activation analysis (NAA) and atomic absorption spectrometry (AAS) methods. Based on the results of measurements conducted using the AAS and NAA methods, it can be concluded that the dominant element in the reed beds at all four specified sites of interest is potassium. It is bioaccumulated in the aboveground part of the plant. The highest concentration of potassium was found in the aboveground part of the reeds from the Karvinský potok site; the lowest was observed in the aboveground part of the reeds from the Nový rybník site. The growth analysis was not conducted according to the methodology, but another interesting finding is that reed beds from the Nový rybník site exhibited the best tolerance to salt stress and the gradual process of salinization with 1% to 5% solutions of Darkov salt. [ABSTRACT FROM AUTHOR]

This project evaluated the potential of common reed to recover heavy metals as valuable products. Common reeds were grown in 25, 50, or 75 ppm Ni2+ and/or Cu2+ solutions for 4 weeks to evaluate its potential to uptake metals followed by converting the contaminated biomass to valuable products by hydrothermal conversion (HTC). The higher concentration of metals in solution, the more metals accumulated in plants. Most metals were sequestered in the roots of reeds. Roots and stems treated with binary metals contained less Ni2+/Cu2+ than those cultured in single metal. The yields of bio-oils and hydrochars from reeds treated with different levels of metals were similar. About 6–10% of the total biomass were transferred to bio-oil, while 50–60% of the biomass were produced as hydrochars. The results suggest that metal accumulated in reeds does not affect the utilization of contaminated reeds via HTC. About 0.1–1.5% of Cu2+ and/or Ni2+ absorbed in biomass were transmitted from contaminated reeds to bio-oils after HTC at 250 °C. [ABSTRACT FROM AUTHOR]

Invasion of Phragmites australis (common reed) in wetlands throughout North America, and particularly the Laurentian Great Lakes Basin, poses significant ecological problems. The extended period of low Great Lakes water levels from 2000 to 2013 created conditions for large expansions of Phragmites in the Great Lakes coastal zone. The following extended period of high water in the Great Lakes during late 2010's, culminating in record high lake levels in 2020 allowed managers to take advantage of high water by using a cut-to-drown management strategy (i.e., cutting plants below the water surface to stop the flow of atmospheric gases) to control Phragmites populations. To examine the efficacy of a cut-to-drown control strategy, we conducted a controlled-greenhouse study that tested the effect of submergence and timing of cutting (early or late in growing season) on Phragmites growth and viability post treatment. To evaluate Phragmites growth and viability, we measured belowground biomass, rhizome non-structural carbohydrate content (NSC), and rhizome viability following a cut-to-drown treatment. Applying a cut-to-drown treatment reduced average belowground biomass production up to 99%, limited rhizome NSC content up to 83%, and inhibited rhizome viability, regardless of timing of cutting treatments. These results suggest that under high-water conditions, utilizing a cut-to-drown strategy has potential for being a useful control mechanism for Phragmites. However, further research is needed to determine to what extent these results will lead to sustained reductions in growth and viability under field conditions, where rhizome belowground biomass and storage capacity are much larger. [ABSTRACT FROM AUTHOR]

Field releases of the stem-boring moths Archanara neurica and Lenisa geminipuncta (Lepidoptera: Noctuidae) as classical biological control agents for introduced Phragmites australis australis (Cav.) Trin. ex Steud. began in Canada during 2019. Since then, we have developed and tested release methods for eggs and larvae of both agents. Experiments here include comparisons of: (1) egg survival from exposed “egg card” and protected “egg cup” release methods to assess the risk of agent predation and test mitigation strategies; (2) performance of egg cups overwintered at the release site and those placed shortly before emergence in spring to test for any potential phenological asynchrony between biological control agents and the target weed; and (3) effectiveness of egg cup and larval-inoculated stem releases at a large geographic scale across 15 field sites in southern Ontario. Egg card releases experienced high egg loss likely due to predation (∼90 % of eggs), but egg cups were successful at reducing these losses to near zero. Releasing eggs in cups during the spring made it easier to place releases near phenologically synchronized microsites, minimized the risk of damage to the egg cups, and avoided a 16 % reduction in egg hatch likely associated with desiccation. Both larval-inoculated stems and egg cups produced highly encouraging feeding damage in the first season of release, with 7.7-fold higher damage from stem larvae compared to egg cups. Overall, we recommend a combination of larval-inoculated stems and spring egg cups for the primary release strategies of A. neurica and L. geminipuncta as biological control agents of introduced Phragmites. Both methods offer protection from predation and varying degrees of control over phenological mismatches. The release of larval-inoculated stems is a more labour-intensive but highly effective method in terms of initial feeding damage whereas egg cups are a more efficient mass-release method than stems with a lower amount of initial feeding damage per agent released.

Introduction: The recent development of extensively antibiotic resistant bacteria has necessitated the search for novel anti-bacterial compounds. An examination of aromatic plants and traditional medicines is an attractive option for drug discovery. Phragmites australis (Cav.) Trin. Ex Steud. Reed is native to many regions globally, including Australia. It has yet to be tested for antibacterial activity. Materials and Methods: The ability of P. australis leaf extracts to inhibit the growth of a panel of bacterial pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: P. australis leaf methanolic and aqueous extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria. The extracts were nontoxic in the Artemia nauplii bioassay following 24 hr exposure. Conclusion: P. australis leaf extracts were completely ineffective bacterial growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Both genetic and phenotypic intraspecific diversity play a crucial role in the ecological and evolutionary dynamics of organisms. Several studies have compared phenotypic divergence (Pst) and differentiation of neutral loci (Fst) to infer the relative roles of genetic drift and natural selection in population differentiation (Pst–Fst comparison). For the first time, we have assessed and compared the genetic variation and differentiation at the leaf trait level in two key macrophytes, Phragmites australis and Nuphar lutea.To this aim, we quantified and described the genetic structure and phenotypic diversity of both species in five lake systems in north‐central Italy. We then investigated the relative roles of genetic drift and natural selection on leaf trait differentiation (Pst–Fst), assuming that Fst reflects divergence caused only by genetic drift while Pst also incorporates the effects of selective dynamics on the phenotype.In terms of genetic structure, the results for P. australis were in line with those observed for other Italian and European conspecific populations. Conversely, N. lutea showed a more complex genetic structure than expected at the site level, probably due to the combined effect of genetic isolation and its mixed mating system. Both species exhibited high variability in leaf functional traits within and among sites, highlighting a high degree of phenotypic plasticity. Pst–Fst comparisons showed a general tendency towards directional selection in P. australis and a more complex pattern in N. lutea. Indeed, the drivers of phenotypic differentiation in N. lutea showed a variable mix of stabilising and directional selection or neutral divergence at most sites.The prevalence of vegetative over generative reproduction leads P. australis populations to be dominated by a few clones that are well adapted to local conditions, including phenotypes that respond plastically to the environment. In contrast, in N. lutea, the interaction of a mixed mating system and geographical isolation among distant sites tends to reduce the effect of outbreeding depression and provides the genetic basis for adaptive capacity.The first joint analysis of the genetic structure of these two key macrophytes allowed a better understanding of the relative roles of genetic drift and natural selection in the diversification of phenotypic traits within habitats dominated by P. australis and N. lutea. [ABSTRACT FROM AUTHOR]

The present study investigates the impact of water level regulation on the growth of common reed (Phragmites australis), a globally widespread helophytic plant. The investigation has been carried out in the Bolle di Magadino (municipalities of Locarno, Gambarogno, Gordola and Tenero; Ticino, Switzerland), a lacustrine-riparian nature reserve in the context of the Lake Maggiore (that stretches between Italy and Switzerland). This is an oligotrophic, artificially regulated lake. Our initial hypothesis was that variation in water table regulation is the most influential factor for explaining observed local reed dieback. To test this, culm height of P. australis was measured at each significant change in lake water level (water table height increase greater than 20 cm), or monthly in the case of a relatively constant lake level. The study took place between 2020 and 2022, monitoring 14 plots of 400 m2, placed at three different relative elevation classes with respect to the level of the lake (5 plots at low elevation, 193.701 m). The results showed that P. australis growth is significantly influenced by the lake water level and thus the relative elevation of the stands, with lower lake levels leading to better growth, especially during the early phases of the growing season. On the other hand, prolonged flooding of shoots significantly impaired common reed growth. The study identifies two relevant relative elevation thresholds for winter mowing, a management practice that enhances reedbeds health. Mowing below 193.20 m elevation is considered risky, as no healthy reedbeds have been observed below this threshold. Mowing below an elevation of 193.50 m was defined as possibly risky, due to observed dieback in some areas as well as healthy reedbeds in other locations at the same or lower elevations. The research also discussed the potential impact of future changes in water level regulation, including the planned change in the spring regulation threshold (+1.50 m above the hydrometric zero in Sesto Calende). This is expected to result in a further rearrangement in lacustrine vegetation, with the growth optimum for P. australis becoming higher and an increase in clumping habit. In conclusion, this study provides valuable insights into the impact of water level regulation on the growth of P. australis in the Bolle di Magadino nature reserve. The research highlights the need for careful management of water level regulation to preserve the reedbed ecosystem and identifies relevant elevation thresholds for winter mowing to mitigate the risks of reed dieback. The findings can inform future management strategies for the Bolle di Magadino reserve and other similar ecosystems facing the challenges of artificial regulation of water levels.

The metabolome represents an important functional trait likely important to plant invasion success, but we have a limited understanding of whether the entire metabolome or targeted groups of compounds confer an advantage to invasive as compared to native taxa. We conducted a lipidomic and metabolomic analysis of the cosmopolitan wetland grass Phragmites australis. We classified features into metabolic pathways, subclasses, and classes. Subsequently, we used Random Forests to identify informative features to differentiate five phylogeographic and ecologically distinct lineages: European native, North American invasive, North American native, Gulf, and Delta. We found that lineages had unique phytochemical fingerprints, although there was overlap between the North American invasive and North American native lineages. Furthermore, we found that divergence in phytochemical diversity was driven by compound evenness rather than metabolite richness. Interestingly, the North American invasive lineage had greater chemical evenness than the Delta and Gulf lineages but lower evenness than the North American native lineage. Our results suggest that metabolomic evenness may represent a critical functional trait within a plant species. Its role in invasion success, resistance to herbivory, and large-scale die-off events common to this and other plant species remain to be investigated. [ABSTRACT FROM AUTHOR]

Constructed wetlands (CWs) are effective and sustainable engineered systems for domestic and/or municipal wastewater treatments. In the last half-century, CWs have become common solutions for small communities in remote mountainous areas. However, cold climate in mountain environment often causes a significant reduction of the pollutant removal performance compared to warmer environments. Therefore, in the present study, we aim to support build consensus on the best design practices for CWs in mountain environments. A meta-analysis of the scientific literature focusing on the CWs in cold climate was conducted. Meanwhile, several monitoring activities (chemical analysis on wastewater and treated water and analysis of changes in the plant communities) were carried out on 6 CWs observing the different conditions between immediately after the construction and 2–7 years later. The results showed an encouraging agreement between scientific studies and observations from the monitored case studies. Lack of plan space, low temperatures and supply meteoric inflows prompted the engineers, in the case studies, to design systems composed of septic tank and horizontal subsurface bed. Such a solution showed a good treatment efficiency (removal rates were more than 60% for most pollutants) in a harsh mountainous environment. A significant difference was evident in the choice of plants. Although the common reeds (Phragmites australis) remain an excellent solution, in plain and hilly areas, planting of tufted hairgrass (Deschampsia cespitosa) ensures similar average performance but is more suitable for the mountain ecosystems. In conclusion, the present study proposes technical and engineering recommendations and a sort of ecological design to increase wastewater treatment efficiency and adapt the systems to a natural and cold environment. [ABSTRACT FROM AUTHOR]

Modern urban societies generate tremendous amounts of hazardous wastes, including toxic organics and metals. Toxic metals harm plants and pose a risk to human health; examples of them are copper (Cu), zinc (Zn), palladium (Pb), and cadmium (Cd). Wetland plants are excellent for the ecological restoration of toxic metal-affected environments. Phragmites australis (common reed) belongs to the family Poaceae and is a broadly distributed wetland grass that is native to Bahrain, Europe, and America. P. australis shows a high content of chlorophyll. This study aimed to assess percentages of water, chlorophyll, and toxic metal content using acetone extraction; the calculation of the concentrations was performed according to the equations proposed by Lichtenthaler and the percentage of water content was calculated. After the metal exposure, the reed plants were digested, and their total mineral analysis was accomplished by atomic absorption spectroscopy; statistical analysis was conducted by Statistical Package for the Social Sciences (SPSS) version 21. The results revealed that the immature stage showed the highest chlorophyll a (mean 1641.5 (µg/g)) carotenoids (mean 359.75 (µg/g)) and total chlorophyll (mean 2183.93 (µg/g)), and the mature flowering stem had the highest chlorophyll b (mean 676.45 (µg/g)). The mature flowering stem stage showed the highest Pb (mg/L) and Cd (mg/L) values; on the other hand, Cu was the highest in the fully elongated non-flowering stage (0.108 mg/L), and the highest Zn content was found in the immature stage (mean 2.083). Owing to its growth in contaminated environments, P. australis can be considered a potential source of phytonutrients; higher concentrations were mostly available in the immature and mature flowering stages, with a favorable immature stage. The use of such marginal wetland plants may be very useful in reducing the pollution burden of urban built environments. These plants offer a green and sustainable solution for the disposal of waste from urban areas. Hence, further planning and execution of such a green solution are pivotal for creating environmental sustainability. [ABSTRACT FROM AUTHOR]

An invasion of Roseau cane scale, Nipponaclerda biwakoensis, native to East Asia, is associated with recent widespread dieback of common reed stands in the Mississippi River Delta, Louisiana. A previous study suggested that, in its native range, the combined mortality from Common Reed Bunting Emberiza schoeniclus and parasitoid wasps may control the abundance of Roseau cane scale. However, there is limited knowledge about which other bird species may prey on Roseau cane scale or the feeding patterns of these birds. Here we used web search and citizen science monitoring data to tabulate bird predation events on Roseau cane scales across sites in Japan and determine which bird species may be the most important predators and when the observed feeding typically occurs. We scanned web entries using both Google image searches and the social networking services including Twitter, Instagram, and Facebook. Additionally, we accessed long‐term field observation records obtained by volunteer monitoring conducted by the members of the Kanagawa Branch of the Wild Bird Society of Japan. By using these citizen science approaches, we detected 16 bird species, mainly Common Reed Bunting but also other migratory and resident species, preying on the Roseau cane scale in reed beds throughout central Japan and most detection occurred during the winter. This study demonstrates that biological information obtained from publicly available data from citizen observers can be useful for exploring ecological patterns of various species including potential predators against invasive species. [ABSTRACT FROM AUTHOR]

Abstract An invasion of Roseau cane scale, Nipponaclerda biwakoensis, native to East Asia, is associated with recent widespread dieback of common reed stands in the Mississippi River Delta, Louisiana. A previous study suggested that, in its native range, the combined mortality from Common Reed Bunting Emberiza schoeniclus and parasitoid wasps may control the abundance of Roseau cane scale. However, there is limited knowledge about which other bird species may prey on Roseau cane scale or the feeding patterns of these birds. Here we used web search and citizen science monitoring data to tabulate bird predation events on Roseau cane scales across sites in Japan and determine which bird species may be the most important predators and when the observed feeding typically occurs. We scanned web entries using both Google image searches and the social networking services including Twitter, Instagram, and Facebook. Additionally, we accessed long‐term field observation records obtained by volunteer monitoring conducted by the members of the Kanagawa Branch of the Wild Bird Society of Japan. By using these citizen science approaches, we detected 16 bird species, mainly Common Reed Bunting but also other migratory and resident species, preying on the Roseau cane scale in reed beds throughout central Japan and most detection occurred during the winter. This study demonstrates that biological information obtained from publicly available data from citizen observers can be useful for exploring ecological patterns of various species including potential predators against invasive species.

Constructed wetlands are environmental solutions that mitigate the impacts of urban effluents. It is unclear how the performance of these wastewater treatment plants (WWTP) is affected by climatic conditions. The dissipation of nutrients, suspended solids, and changes in dissolved oxygen were investigated on a monthly basis over two years (2018/2019) at six sampling points across a WWTP located in Esquel, Patagonia. It was predicted that climatic variables (rain pattern and air temperature) would affect the functioning and efficiency of the WWTP (i.e., via nutrient load mitigation and sediment retention). Rainfall and temporal patterns differed markedly between and throughout the two years, leading to a clear seasonality in the transformation of pollutants. Nitrate loads were significantly higher in 2018 than in 2019 suggesting some degree of operational failure, whereas ammonia levels in treated effluents were extremely high during both years, with marked peaks occurring during autumn 2018 and summer 2019. The WWTP was moderately successful (~36%) in reducing TSS contents during 2018 but was inefficient in 2019. Ammonia levels in receiving waters underwent dilution due to rains rather than due to adequate WWTP nutrient retention. In terms of nutrients, effluent values exceeded those established by governmental regulation during most months, but worsened during summer coinciding with low flows. This lack of predictability for the values of the treated effluent strongly jeopardizes the ecological integrity and biodiversity of the receiving stream. [ABSTRACT FROM AUTHOR]

Measures mitigating the climate crisis, such as paludiculture, which is the agriculture on rewetted peatlands, are urgently needed. The cosmopolitan species Phragmites australis has the potential to be used in paludiculture worldwide but is known for its high intraspecific variation. This raises the questions of whether (i) P. australis genotypes differ even at a regional scale, making them differently well suited for paludiculture and (ii) P. australis performance can be predicted by linking the variation in genotypes to strategies in the plant economics spectrum. Five P. australis genotypes from Mecklenburg-Western Pomerania were cultivated in two 10-month mesocosm experiments along gradients of water level and nutrient addition. We compared growth, morphology (height, growing density), above- and belowground biomass, functional and ecophysiological traits (SLA, LDMC, SRL, RDMC, root porosity, photosynthetic rate) as well as gene expression. Our results demonstrate a high variability of P. australis genotypes even at a regional scale, revealing genotype-specific productivity, morphology, and gene expression and implying that the selection of suitable genotypes will be crucial for the success of a paludiculture. However, trait covariation did not indicate distinct plant economic strategies to predict genotype performance. Instead, large-scale genotype trials are needed to select suitable genotypes for paludiculture. [ABSTRACT FROM AUTHOR]

Common reed (Phragmites australis) is growing naturally in wetlands and is not adequately evaluated. The aim of the study was to determine the fermentative, nutritive, and anti-nutritive composition of the common reed and silage. The plant was cut from the reed area is ensiled in 1.5 L anaerobic jars with 10 replicates. The crude protein content of the plant was 14.44%, and 14.47% respectively in raw and silage. The crude ash was 9.46% in raw, 9.12% in its silage. The neutral and acid detergent fibers were 66.91% and 42.93% in raw, 65.45%, and 43.20% in the silage respectively. The pH value was 7.37 in raw and 4.32 in its silage. The organic matter digestibility was 61.99% in raw and 62.10% of its silage. The metabolic energy and net energy lactation values were 8.32 and 4.48 MJ/kg DM in raw, 8.25 and 4.35 MJ/kg DM in silage. The digestible dry matter, dry matter intake, and relative feed value contents were 55.44%, 1.82%, and 78.20 in raw; 51.32%, 1.83%, and 72.81 in the silage respectively. The in vitro methane production was decreased in silage compared the raw material. The silage Fleig point was in "very good" class. The lactic, acetic propionic and butyric acids in silage were 76.49, 21.91, 11.00, and 3.99 g/kg DM, respectively. The calcium and phosphorus contents were 9.22–9.13 g/kg, and 3.36–3.40 g/kg, in raw and silage respectively. The plant fatty acid composition has more than 50% unsaturated fatty acids. The lysine and methionine concentrations were determined as 5.01–5.09 and 0.40–0.42 g/kg DM, respectively. As a result, it has been determined that Phragmites australis can be used as roughage feed for animals and can be ensiling. [ABSTRACT FROM AUTHOR]

Simple Summary: This study assesses the state of mercury pollution in the ecosystems of two studied lakes and indicates which species of fish are safe for consumption by determining mercury levels in selected elements of the lake environment. It also examines the impact of selected biotic (length and weight of fish) and abiotic (Hg content, pH, O2 in water and sediment, water transparency) factors on the ability of fauna and flora to bioaccumulate mercury. Based on the maximum residue levels (MRLs), the muscles of pike, bream and roach from both lakes were found to be safe for consumption. No significant health risk was identified based on estimated daily intake (EDI), target hazard quotient (THQ) and tolerable weekly intake (TWI) values. Mercury, which tends to bioaccumulate and biomagnify in aquatic food webs, poses a potential health risk to wildlife and to consumers of predatory fish in particular. Its concentration in biota can be high even at low environmental concentrations. Therefore, the aim of this study was to determine mercury in both abiotic (water and sediment) and biotic elements (common reed (Phragmites australis) and fish: pike (Esox lucius), bream (Abramis brama) and roach (Rutilus rutilus)) in the context of assessing the pollution of two lakes in Poland and the safety of fish consumers. The possibility of Hg biomagnification in fish was also considered. Mercury was determined by means of cold vapor atomic absorption spectrometry (CVAAS). The concentrations of Hg in water and bottom sediments of Lake Ińsko were lower than in Lake Wisola. In the bottom sediments of both lakes, a positive correlation was found between the Hg content and organic matter. The concentration of mercury in the organs of common reed did not exceed 0.017 mg/kg dry weight (dw), and its distribution can be presented as follows: root > leaves > stems > rhizomes. In fish organs from both lakes, the average mercury content did not exceed 0.086 mg/kg of wet weight (ww) and in most cases it was the highest in pike. Higher values were only observed in the muscles and skin of roach. This indicates a lack of biomagnification in the relationships between planktivorous-predatory and benthivores-predatory fish. Based on the maximum levels of mercury in fish and the calculated parameters, i.e., estimated daily intake (EDI), target hazard quotient (THQ) and tolerable weekly intake (TWI), the muscles of the examined fish were found to be safe for consumption. The average dietary exposure to total mercury (THg) and methylmercury (MeHg) was below 0.3% of the TWI. [ABSTRACT FROM AUTHOR]

Wetlands are important global carbon sinks, an increasingly important ecosystem service. Invasive plants can disrupt wetland carbon budgets, although efforts to suppress invasive plants may also have unintended effects. Invasive Phragmites australis subsp. australis (European common reed) produces extensive monocultures that displace resident plant communities. In Long Point (Ontario, Canada), a glyphosate-based herbicide was used to control over 900 ha of P. australis. We determined how this ongoing management, and different environmental conditions, influence net primary productivity and decomposition rates. We compared above- and below-ground biomass, belowground:aboveground biomass ratios, standing dead stems, and litter in un-treated P. australis stands, in herbicide-treated areas, and in reference vegetation. We also conducted a reciprocal transplant experiment to measure the decomposition rates of plant litter. One-year post-treatment, control efforts dramatically reduced aboveground biomass (122 g/m2 ± 133 SD) compared to un-treated P. australis (1254 g/m2 ± 449 SD) and reference habitat (821 g/m2 ± 335 SD). An interaction between the plant community of the site and water depth predicted litter decomposition rates, with litter loss ranging from 5.75 to 74.65% across all species, and submerged litter decomposing faster. These results emphasize that secondary treatment, such as rolling, burning, or cutting, encourages the decomposition of dead P. australis stems, opening up space for the recovery of native plants. While herbicide-treated sites had low biomass immediately following treatment, aquatic vegetation began rapidly colonizing treated areas, suggesting that plant community recovery may restore the wetland carbon uptake in subsequent years. [ABSTRACT FROM AUTHOR]

The aim of the present study was to provide a comparative analysis related to the concentration of heavy metals (Cd, Pb, Ni, Cr) in the tissues (stem, leaves, panicle) of the common reed (Phragmites australis). The reed samples were collected from 10 different sampling stations located in Danube Delta Reservation Biosphere, 2 sampling station from Lake Brate? and 2 sampling station situated on a tributary of the Danube River (Chineja River), Romania. The concentration of heavy metals varied depending on the location, the lowest values were found in plants located on the course of the Chineja River. As well, depending on the plant structure, was observed that the panicle contained the lowest concentrations of the chosen heavy metals for the experiment. [ABSTRACT FROM AUTHOR]

Successful invasive plant management—where invaders are sufficiently reduced and diverse native plant communities recover—remains an elusive goal for land managers. The site‐ and landscape‐scale drivers of variable management outcomes and vegetation recovery are poorly understood due to a lack of rigorous experiments that characterize longer term vegetation trends across contexts. We present the results of a five‐year experiment across eight subestuaries of Chesapeake Bay, representing a gradient of watersheds with differing dominant land‐use types and anthropogenic impacts, to evaluate invasive and native plant response to herbicide management. The focal invader, Phragmites australis (common reed), is one of the most aggressive and pervasive invasive plants in North American wetlands. We found that with multiyear herbicide treatments, it was possible to greatly reduce Phragmites across an array of subestuaries while increasing the cover and quality of native plant communities. Yet, by the end of the study, plant community composition in all Phragmites‐managed sites remained distinct from, even if composition was shifting toward, reference sites. There was also large inter‐site variation in the vegetation responses related to site environmental conditions and subestuary vegetation conditions. We uncovered specific aspects of the surrounding landscape that were linked to improved vegetation recovery—the species richness and conservation value of nearby wetlands. Results from this five‐year experiment conducted at multiple sites in Chesapeake Bay inform what is possible for management, particularly in more degraded landscapes and sites where setting realistic expectations and pragmatic goals will be essential. Assessing environmental and vegetation conditions of the site and surrounding landscape prior to commencing invasive species management is critical to predict the time and effort required to achieve restoration goals. [ABSTRACT FROM AUTHOR]

Phragmites australis exhibits substantial tolerance for salt and heavy metals exposure in the environment. The purpose of this study was to evaluate some biochemical parameters of Phragmites australis irrigated with wastewater (containing nickel, zinc, copper, iron, cadmium, and lead) up to the vegetative (short term), flowering (average term), or reproductive (long term) stage. The plant samples were collected twice i.e., two days and four days after irrigation at each growth stage. The plants were irrigated with freshwater for control. The average-term application of wastewater causes to higher biomass than the control plants. Some physicochemical parameters (proline, electrical conductivity, total soluble protein, and potassium) were more strongly correlated with plant biomass. The chlorophyll a, chlorophyll b, total chlorophyll, and total soluble proteins were reduced at the reproductive stage. While, the proline, soluble sugars, and activities of antioxidant enzymes were increased. Long-term wastewater exposure led to a significant increase in sodium, potassium, and Na+/Ca2+ ratio of P. australis while magnesium contents were decreased by wastewater irrigation. The present findings suggest that P. australis possess several enzymatic and non-enzymatic defense processes that curtail oxidative stress caused by heavy metals toxicity from wastewater and protect photosynthetic pigments from damage in the flowering stage. [ABSTRACT FROM AUTHOR]

Abstract Successful invasive plant management—where invaders are sufficiently reduced and diverse native plant communities recover—remains an elusive goal for land managers. The site‐ and landscape‐scale drivers of variable management outcomes and vegetation recovery are poorly understood due to a lack of rigorous experiments that characterize longer term vegetation trends across contexts. We present the results of a five‐year experiment across eight subestuaries of Chesapeake Bay, representing a gradient of watersheds with differing dominant land‐use types and anthropogenic impacts, to evaluate invasive and native plant response to herbicide management. The focal invader, Phragmites australis (common reed), is one of the most aggressive and pervasive invasive plants in North American wetlands. We found that with multiyear herbicide treatments, it was possible to greatly reduce Phragmites across an array of subestuaries while increasing the cover and quality of native plant communities. Yet, by the end of the study, plant community composition in all Phragmites‐managed sites remained distinct from, even if composition was shifting toward, reference sites. There was also large inter‐site variation in the vegetation responses related to site environmental conditions and subestuary vegetation conditions. We uncovered specific aspects of the surrounding landscape that were linked to improved vegetation recovery—the species richness and conservation value of nearby wetlands. Results from this five‐year experiment conducted at multiple sites in Chesapeake Bay inform what is possible for management, particularly in more degraded landscapes and sites where setting realistic expectations and pragmatic goals will be essential. Assessing environmental and vegetation conditions of the site and surrounding landscape prior to commencing invasive species management is critical to predict the time and effort required to achieve restoration goals.

We isolated Haematospirillum jordaniae from a positive blood culture from a 57-year-old man in Slovenia who had bacteremia and bullous cellulitis of lower extremities. The infection was successfully treated with ciprofloxacin. Our findings signal the need for increased awareness about the clinical course of H. jordaniae and its potential effects as a human pathogen. [ABSTRACT FROM AUTHOR]

Water-use characteristics are important aspects of plant adaptation to environmental factors. While water-use efficiency (WUE) and water sources used by plants in arid habitats are commonly studied, water-use strategies of plants in coastal wetlands are poorly studied. Although ample water is available in coastal wetlands, water conditions vary among seasons, suggesting that the plant in coastal wetlands may need to adapt to seasonal changes in water availability.To uncover temporal variation in plant water-use strategies in the coastal wetland, we investigated WUE and water sources used by Phragmites australis in the tidal marsh of the Yellow River Delta employing stable isotopic composition indicators. Temporal variation of δ13C and δ18O in leaf organic matter were measured in two years (2018 and 2019) along with plant traits and environmental factors, to determine the factors affecting δ13C and δ18O in leaf organic matter. Water sources (rainfall, soil water in different depths, tidal water, and groundwater) were sampled for δ18O composition in the early growth season (2019 May, June, and July) to determine water sources using the Bayesian mixing model MixSIAR.We found that P. australis had high WUE in spring and autumn, but WUE declined during summer. Changes in WUE were explained by variation in plant height, leaf nutrient concentrations (C: N, total N, total S), leaf traits (leaf length and leaf number), soil electronic conductivity (EC), soil pH, soil nutrients (NO3-N at 0–30 cm soil depth, total S at 0–30 cm soil depth, available P at the soil depths of 0–10 cm and 40–50 cm, and total C at the 30–40 cm soil depth). Spring drought may enhance WUE through increasing soil salinity (i.e., EC) and lowering pH. Water uptake in the early growth season was composed mainly of rainfall, soil water, and groundwater. However, tidal water (i.e., ocean water) was not a main water source. To sum up, leaf WUE varied with seasons in the coastal wetland, which may be related to plant traits and soil factors, particularly salinity and pH. The plant in the tidal marsh may not take up ocean water, even though it is really abundant. Precipitation is still an important water source promoting growth of these plants in the coastal wetland, therefore, to conserve them, supplementing fresh water in the drought season is suggested.

Anthropogenic activities can be the source of saline solid wastes that need to be treated to reduce their salt load to meet the purposes of reuse, valorization or storage. In this context, chloride remediation can be achieved using high-salt accumulating plants. However, there is very limited information on the comparative potential of different species in the same environment, and only scarce data concerning their efficiency as a function of growth stage. In order to rationalize these selection criteria, three macrophytes i.e., common reed (Phragmites australis), sea rush (Juncus maritimus), and cattail (Typha latifolia), were cultivated at two growth stages (6-months old and 1-year old) for 65 days in Cl− spiked substrates (from 0 up to 24 ‰ NaCl). The plants' survival and potential capacity for removal of Cl− from substrates and accumulation in shoots were investigated. For the three studied species, mature and juvenile plants display a high tolerance to salinity. However, mature specimens with higher shoot biomass and Cl− contents are capable of greater chloride removal than juvenile plants. The sole exception is P. australis which displays just the same phytoremediation potential for both mature and juvenile specimens. Moreover, P. australis has the lowest potential when compared with other species, being 1.5 and 3 times lower than for J. maritimus and T. latifolia. When considering the plant growth and the shoot biomass production, chloride removal rates from the substrate point that mature J. maritimus should preferentially be used to design an operational chloride remediation system. The results highlight the relevance of considering the growth stage of plants used for Cl− removal. Highlights: 1) Mature and juvenile specimens of J. maritimus, P. australis, and T. latifolia have high salinity tolerance in solid media spiked up to 24 ‰ NaCl. 2) Mature plants have generally better Cl− removal and phytoremediation performances than juvenile specimens. 3) J. maritimus is the most effective species for chloride phytoremediation with high survival and high Cl− sequestration in shoots. 4) T. latifolia has high Cl− removal in shoots and good remediation capacities but also shows sign of stress. 5) P. australis shows low Cl− sequestration and is a poor candidate for chloride remediation from substrate. [ABSTRACT FROM AUTHOR]

Anthropogenic habitats that are contaminated by toxic elements were recently shown to host abundant and diverse assemblages of bees and wasps (Hymenoptera: Aculeata), including numerous threatened species. However, toxic elements adversely affect insect fitness. We address the effects of toxic elements on aculeate inquilines that occupy Lipara lucens-induced galls on the common reed, Phragmites australis. We hypothesized that contamination of potential nesting and feeding habitats is associated with adverse changes in bee and wasp populations that are attracted in these environments. To address this hypothesis, we analyzed the contents of As, Cd, Cu, Pb, Zn, Fe, and S in site-matched samples of soil, reed galls, and crabronid wasp bodies and correlated them with abundance and species richness of aculeate hymenopterans in reed galls and with the number of larvae in nests of the eudominant hymenopteran, Pemphredon fabricii. The common reed was present at all the examined sites, and L. lucens-induced galls were present at all but one sampling site; the single exception was the sampling site with the highest contents of four of the seven analyzed elements. The alpha diversity of gall-associated aculeate inquilines, abundance of P. fabricii, and number of prepupae per nest of P. fabricii were not correlated with the contents of any of the seven analyzed toxic elements. We found P. fabricii to be abundantly present in habitats with extreme concentrations of toxic elements. Exposed P. fabricii accumulated Cd, Cu, and Pb, while they eliminated Fe and Zn. The obtained data did not support the hypothesis that heavy metal contamination of anthropogenic sites affects P. fabricii and other reed gall-associated aculeates. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the potential of the emergent macrophytes Phragmites australis to remediate nutrients and restore an eutrophic wetland (Lake Burullus, Egypt). The plant was sampled monthly for one year from 6 sites distributed equally along the northern and southern parts of this lake. Monthly significant variation in all investigated sediment and water nutrients for the northern and southern sites was recorded. The biomass of P. australis in the southern sites was greater than that of the northern sites; in addition, the above-ground biomass was greater than the below-ground biomass. The above-ground biomass increased from February until it reached its maximum during August and then decreased again. Likewise, the highest nutrient concentrations in the different tissues were recorded at the beginning of the growing season during winter and early spring and then gradually decreased with increasing plant biomass. Moreover, the nutrient content (g/m2) increased from the early growing season (February) and reached its peak during April–August and then decreased. Based on our results, P. australis could be used for the extraction of nutrients to reduce the eutrophication in Lake Burullus, if the above-ground biomass is harvested at its maximum value in August, as was the case regarding the maximum content of most nutrients.

The paper presents the results of calculations and a verification of numerical models developed for estimating the surface of leaves of the common reed (Phragmites australis (Cav.) Trin. Ex Steud.). The research sample consisted of 137 leaves collected from the rush zone of Lake Raduńskie Górne in 2018. The total area of leaves obtained for testing was 1932.3 cm2. To derive a formula that returns the surface of common reed foliage regression models were used – MLR (Multiple Linear Regression) and SLR (Stepwise Linear Regression). It has been shown that the measurement of basic leaf dimensions (i.e. length – L, mid-width – WM and maximum width – WX) makes it possible to define an empirical formula which, with an average accuracy of 99.9%, allows the real surface of leaves to be estimated. The modelling results were compared with formulas currently used in practice, and the measurement errors were determined using these formulas. It has been shown that the formulas used to date are subject to RMSE to the value of 1.19-2.52. The application of the developed formula (A = 0.4486 – 0.046 L + 7.9267 WM – 5.8121 WX + 0.5853 L • WX) will significantly reduce errors in leaf surface estimation (RMSE = 0.86) and thus the amount of reed transpiration and evapotranspiration, especially in the case of handling small samples (number of leaves and measurements).

Modern urban societies generate tremendous amounts of hazardous wastes, including toxic organics and metals. Toxic metals harm plants and pose a risk to human health; examples of them are copper (Cu), zinc (Zn), palladium (Pb), and cadmium (Cd). Wetland plants are excellent for the ecological restoration of toxic metal-affected environments. Phragmites australis (common reed) belongs to the family Poaceae and is a broadly distributed wetland grass that is native to Bahrain, Europe, and America. P. australis shows a high content of chlorophyll. This study aimed to assess percentages of water, chlorophyll, and toxic metal content using acetone extraction; the calculation of the concentrations was performed according to the equations proposed by Lichtenthaler and the percentage of water content was calculated. After the metal exposure, the reed plants were digested, and their total mineral analysis was accomplished by atomic absorption spectroscopy; statistical analysis was conducted by Statistical Package for the Social Sciences (SPSS) version 21. The results revealed that the immature stage showed the highest chlorophyll a (mean 1641.5 (µg/g)) carotenoids (mean 359.75 (µg/g)) and total chlorophyll (mean 2183.93 (µg/g)), and the mature flowering stem had the highest chlorophyll b (mean 676.45 (µg/g)). The mature flowering stem stage showed the highest Pb (mg/L) and Cd (mg/L) values; on the other hand, Cu was the highest in the fully elongated non-flowering stage (0.108 mg/L), and the highest Zn content was found in the immature stage (mean 2.083). Owing to its growth in contaminated environments, P. australis can be considered a potential source of phytonutrients; higher concentrations were mostly available in the immature and mature flowering stages, with a favorable immature stage. The use of such marginal wetland plants may be very useful in reducing the pollution burden of urban built environments. These plants offer a green and sustainable solution for the disposal of waste from urban areas. Hence, further planning and execution of such a green solution are pivotal for creating environmental sustainability.