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Invasive species pose a significant threat to global biodiversity, prompting the need for novel management strategies. We investigated the effect of pond placement in preventing colonization by Gambusia holbrooki, an invasive fish impacting amphibians, including the threatened green and golden bell frog (Litoria aurea). Because Gambusia moves between aquatic systems during surface flow events, we aimed to determine whether constructing ponds on elevated plots devoid of fish was less likely to be colonized due to the absence of two‐way water connectivity with sources from below. Over eight consecutive years, we monitored Gambusia presence at 50 ponds within an industrialized area of Kooragang Island, New South Wales, Australia, home to one of the largest extant subpopulations of L. aurea. This included 24 constructed ponds, 19 of which were on elevated plots, along with 26 historic ponds already present prior to the study. None of the ponds constructed on elevated plots were ever colonized by Gambusia during the study period, while most (three out of five) constructed at lower elevation and historical ponds (25 out of 26) were. Our findings indicate that the elevated plots acted as plateau safe havens, with elevation difference rather than proximity to Gambusia sources the key driver preventing colonization. These plateaus are now functioning as some of the only Gambusia‐free breeding habitat for L. aurea in this area. This research highlights the role of landscape topography and intentional pond placement in safeguarding newly constructed wetlands from invasive fish, providing insights for wetland conservation and biodiversity protection. [ABSTRACT FROM AUTHOR]

Thoughtfully managed hydroperiods in natural and artificial wetlands could potentially provide a combination of desirable flood control services and high ecological functions. To explore how managed freshwater wetlands typical of the Houston, Texas area would respond to different hydrological regimes that might occur if wetlands were drained in anticipation of a heavy rain that did not materialize, we conducted a mesocosm experiment with six flooding depths and seven drought durations, followed by seven months of recovery. We found that the speed in which mesocosms dried out was a function of initial water depth, with mesocosms initially set with greater water depths (30 cm) taking ~ 38 days to dry out versus zero days for wetlands that were completely drained. Individual plant species (14 species planted; 8 species common at the end of the recovery period) were affected by drought length, flooding depth, or their interaction, although details of these responses varied among the species. The composition of the plant community at the end of the drought period was strongly affected by drought length, and the effect of the drought length treatment persisted through seven months of post-drought recovery, with the 80- and 160-day drought treatments diverging most strongly from shorter drought treatments. Above- and below-ground biomass of plants was not affected by the treatments, but above-ground dead biomass (litter) decreased with increasing drought length. Densities of mosquito larvae, snails and tadpoles were temporally variable, and were affected more during the treatment period and early in recovery than after a disturbance event late in recovery. Our results indicate that managed wetlands in southeast Texas would be quite resilient to dry periods of up to 40 days in duration, especially if water was not completely drained at the beginning of the drought. In addition, many species would persist in managed wetlands even with droughts of up to 160 days. This indicates considerable potential for managing the hydroperiods of artificial detention ponds by retaining water longer to increase ecological function, with little to no loss of flood control services, and for managing the hydroperiods of natural wetlands by draining them in advance of anticipated rains to increase flood control services, with little to no loss of ecological function. [ABSTRACT FROM AUTHOR]

Mosquitoes (Diptera: Culicidae) are one of the most impactful pests to human society, both as a nuisance and a potential vector of human and animal pathogens. Mosquito larvae develop in still aquatic environments. Eliminating these habitats near high human density or managing them to reduce the suitability for mosquitoes will reduce mosquito populations in these human environments and decrease the overall negative impact of mosquitoes on humans. One common source of standing water in urban and suburban environments is the water that pools in stormwater control measures. Previous studies have shown that some stormwater control measures generate large numbers of mosquitoes while others harbor none, and the reason for this difference remains unclear. Our study focuses on elucidating the factors that cause a stormwater control measure to be more or less suitable for mosquitoes. During the summers of 2021 and 2022, we collected and identified mosquito larvae from thirty stormwater control measures across central Ohio to assess variation in mosquito abundance and diversity among sites. Our goal was to determine if specific types of stormwater control measures (retention ponds, detention ponds, or constructed wetlands) harbored different abundances of mosquitoes or different community structures. We also assessed environmental parameters of these sites to elucidate their effects on mosquito abundance and diversity. Overall, we recorded the highest number of mosquito larvae and species in constructed wetlands. However, these sites were dominated by the innocuous species, Culex territans. Conversely, detention ponds held fewer mosquitoes but a higher proportion of known vector species, including Culex pipiens and Aedes vexans. The total number of mosquitoes across all sites was correlated with higher vegetation, more shade, lower water temperatures, and lower pH, suggesting stormwater control measures with these features may also be hotspots for mosquito proliferation. [ABSTRACT FROM AUTHOR]

The Yellow River Delta (YRD), known for its vast and diverse wetland ecosystem, is the largest estuarine delta in China. However, human activities and climate change have significantly degraded the wetland ecosystem in recent decades in the YRD. Therefore, an understanding of the land use modifications is essential for the efficient management and preservation of ecosystems in this region. This study utilized time series of remote sensing data and the extreme gradient boosting method to generate land use maps of the YRD from 2000 to 2020. Several methods, including transition matrix, land use dynamic degree, and standard deviation ellipse, were employed to explore the characteristics of land use transitions. The results underscore significant spatial variations in land use over the past two decades. The most rapid increase was observed in built-up area, followed by terrestrial water and tidal flats, while unutilized land experienced the fastest decrease, followed by forest–grassland. The spatial distribution patterns of agricultural land, built-up area, terrestrial water, and forest–grassland demonstrated stronger directionality compared to other land use types. The wetlands have expanded in size and improved in structure. Unutilized land has been converted into artificial wetlands comprising ponds, reservoirs, salt ponds, shrimp and crab ponds, and natural wetlands featuring mudflats and forest–grassland. The wetland conservation efforts after 2008 have proven very effective, playing a positive role in ecological and environmental preservation, as well as in regional sustainable development. [ABSTRACT FROM AUTHOR]

This study presents empirical evidence elucidating the utilisation of reed beds by hazel dormice (Muscardinus avellanarius) during their summer activity phase. Historically characterised as an arboreal species confined to woodland and hedgerow habitats, the comprehensive assessment of this strictly protected species within reed beds and analogous wetland ecosystems across Europe has been lacking, presumably due to the presumption of their absence in such locales. This study aimed to employ radio telemetry to monitor hazel dormice and assess their utilisation of a reed bed compared to adjacent woodland for both nocturnal activity and daytime resting. To achieve this aim, eight hazel dormice were fitted with radio transmitters at the boundary between a reed bed and an adjacent woodland and tracked for a minimum of three consecutive nights. Results showed that the animals used the reed bed to a comparable extent to the adjacent woodland during their nocturnal activity. Furthermore, hazel dormice frequently chose resting sites in the reed bed during the day. Although the nesting and breeding behaviour within the reed bed was not thoroughly examined, the discovery of a hazel dormice nest suggests that hazel dormice construct summer nests within the reed bed habitat. Reed beds, particularly when interconnected with adjacent woodland, constitute an integral component of the habitat of the hazel dormouse, a previously overlooked fact. Hence, it is essential to include reed beds in strategies for conservation management and further research aimed at elucidating the habitat requirements of the hazel dormouse. [ABSTRACT FROM AUTHOR]

Wetlands are catchment life support systems with diverse ecological and socio-economic functions. They have played a significant role in the growth of African human civilisations and cultural development, and today contribute billions of US dollars' worth of ecosystem services to the people of Ethiopia. Ethiopia exhibits both natural and man-made wetland types that cover up to 2% of its land surface. They are, however, under threat from excessive pressures that are both ecologically and socially driven. The objective of this study was to analyse the state of ecosystem services provision of the Ethiopian wetlands, with a novel application of Ostrom's Socio-ecological Systems Framework (SESF), taking Boyo Wetland as a case study. Household surveys, focus group discussions and stakeholder analysis methods were applied to satisfy the data needs of SESF. Insufficient knowledge of actors on wetland ecosystem services, weak governance and limited self-organisation among actors are highlighted as the major reasons contributing to the unsustainable use of wetlands. When the use of Boyo Wetland's ecosystem services was evaluated using the SESF, it was evident that unsustainable resource use practices are widespread. These findings could be used to inform national policy on wetlands and local strategies for the sustainable use of wetland resources by direct or indirect users at different levels. [ABSTRACT FROM AUTHOR]

The degradation and loss of natural wetlands has caused severe crises for wetland taxa. Meanwhile, constructed wetlands are expanding significantly and facing dramatic environmental changes. Exploring the responses of wetland organisms, particularly zooplankton, may have important implications for the management of wetlands. Environmental and zooplankton samples were collected from 34 subsidence wetlands created by underground coal mining across the North China Plain in August 2021. We used generalized linear models and redundancy analysis to test zooplankton responses to environmental variables, with the relative importance quantified by variation partitioning. We identified 91 species, divided into 7 functional groups, with the highest density of rotifer filter feeders (RF, 2243.4 ± 499.4 ind./L). Zooplankton species richness was negatively correlated with electrical conductivity (EC), chlorophyll-a, total phosphorus, and pH. The Shannon–Weiner and Pielou evenness indices were positively correlated with transparency and negatively correlated with the photovoltaic panel area (AS). Rotifer predators (RCs) and RF densities were positively correlated with cropland area and dissolved oxygen, but negatively correlated with AS. Small crustacean filter feeders positively correlated with AS, whereas medium crustacean feeders (MCFs) positively correlated with EC. AS was the most critical variable affecting the zooplankton community. Our study showed that the spatial pattern of zooplankton communities was shaped by environmental heterogeneity across the subsidence wetlands, providing implications for the management and conservation of these constructed wetlands. [ABSTRACT FROM AUTHOR]

The primary objective of the present study is to enhance the denitrification process in constructed wetlands (CWs), employed as an ecological and natural technology for wastewater treatment. Eco-friendly approaches have been tested to improve the nitrate removal efficiency in pilot-scale subsurface flow CWs. Initially, the system's performance was enhanced by using a natural substrate, namely cork, as a filter medium. Another approach is bio-inoculation into the rhizosphere of a bacterial strain with the potential capacity for nitrate removal, thereby reinforcing the synergy between the plant and microorganisms. Finally, the approaches were combined, and nitrate removal was assessed. The main results showed that the most effective nitrate removal from wastewater was achieved with cork (80%) compared to gravel (60%). Bio-inoculation into the rhizosphere of denitrifying bacteria significantly improved nitrate removal. Indeed, the nitrate removal rate by the inoculated CW filled with gravel, was higher than the non-inoculated system, with rates of 78% and 60%, respectively. Moreover, the highest removal rate of 99.77% was obtained with the inoculated system filled with cork. [ABSTRACT FROM AUTHOR]

Nature-based solutions (NbSs) are considered to form an innovative stormwater management approach that has living resolutions grounded in natural processes and structures. NbSs offer many other environmental benefits over traditional grey infrastructure, including reduced air pollution and climate change mitigation. This review predominantly centers on the hydrological aspect of NbSs and furnishes a condensed summary of the collective understanding about NbSs as an alternatives for stormwater management. In this study, which employed the CIMO (Context, Intervention, Mechanism, Outcome) framework, a corpus of 187 NbS-related publications (2000–2023) extracted from the Web of Science database were used, and we expounded upon the origins, objectives, and significance of NbSs in urban runoff and climate change, and the operational mechanisms of NbSs (including green roofs, permeable pavements, bioretention systems, and constructed wetlands), which are widely used in urban stormwater management, were also discussed. Additionally, the efficacy of NbSs in improving stormwater quality and quantity is discussed in depth in this study. In particular, the critical role of NbSs in reducing nutrients such as TSS, TN, TP, and COD and heavy metal pollutants such as Fe, Cu, Pb, and Zn is emphasized. Finally, the main barriers encountered in the promotion and application of NbSs in different countries and regions, including financial, technological and physical, regulatory, and public awareness, are listed, and future directions for improving and strategizing NbS implementation are proposed. This review gathered knowledge from diverse sources to provide an overview of NbSs, enhancing the comprehension of their mechanisms and applications. It underscores specific areas requiring future research attention. [ABSTRACT FROM AUTHOR]

Subsurface-flow constructed wetlands (SSF CWs), which include horizontal subsurface–flow constructed wetlands (HSSF CWs) and vertical subsurface–flow constructed wetlands (VSSF CWs), have become increasingly popular for the treatment of various waste streams such as wastewater, landfill leachate, and stormwater runoff. These wetlands utilize a variety of natural physical, chemical, and microbial processes to effectively remove contaminants. This article aims to provide valuable insights into the application of subsurface-flow wetlands for the treatment of stormwater runoff by collecting and reviewing relevant articles. Within the realm of stormwater contaminants, this review primarily focuses on nutrients, heavy metal, and per- and polyfluoroalkyl substances (PFAS), which are commonly found in stormwater runoff worldwide. The removal percentages of these contaminants vary across different studies, depending on factors such as the characteristics of the contaminants, the type and scale of the subsurface-flow wetland, as well as the selection of plants and substrates used. This study provides valuable insights into the various processes that significantly contribute to the removal of contaminants, including adsorption, plant uptake, and biodegradation. The removal percentage of PFAS ranges from 1% to 99% in constructed wetlands. The wide range of PFAS removal comes from differences between PFAS category, plant and soil type, wetland configuration, and matrix effects. Additionally, this paper brings attention to the current gaps and limitations present in the research conducted within this field. It is imperative to conduct further studies utilizing real-world or synthetic stormwater runoff to deepen our comprehension in this domain. Furthermore, considering that each category of PFAS possesses unique properties, conducting individual studies on each group becomes crucial to attain a comprehensive understanding of the behavior and transformation of PFAS in CWs. [ABSTRACT FROM AUTHOR]

Wetlands within dryland regions are highly sensitive to climate change and human activities. Based on three types of land use data sources from satellite images and a spatial data analysis, the spatiotemporal characteristics of wetland evolution in China's drylands and their relationship with human interference and climate change from 1990 to 2020 were analyzed. The results were as follows: (1) The wetlands within China's drylands expanded, including rivers, lakes, and artificial wetlands, apart from marshes, which shrunk. Meanwhile, wetland fragmentation increased, with rivers being particularly severely fragmented. (2) Temperature and precipitation showed an increasing trend from 1990 to 2020 in China's drylands. Lakes and rivers expanded with regional differences due to the uneven distribution of precipitation and rising temperature. (3) Human activities, more than climate change, became the key driving factor for the changes in wetland patterns in China's drylands. The increased areas of farmland and grassland along with increased levels of drainage and irrigation activities led to the shrinkage of marshes and the fragmentation of rivers. The increase in the number of artificial reservoirs was the main reason for the expansion of artificial wetlands. This study clarifies the specific driving factors of different types of wetlands within China's drylands, which is of great use for better protecting wetlands and the gradual restoration of degraded wetlands. [ABSTRACT FROM AUTHOR]

Microorganisms, in particular prokaryotic cells, thanks to their small dimensions, wide metabolic abilities and fast reproduction, adapt continuously to environmental changes. Bacteria and Archaea are ubiquitous and develop promptly resistance to toxic effects of contaminants and capability of removing them through aerobic and anaerobic pathways. They can be used for bioremediation purposes both in bulk soil and in rhizosphere. The rhizosphere is a microhabitat, comprising roots and few millimeter soil/sediment immediately surrounding them, where an intense chemical dialog between plants and microorganisms occurs. Plants and microorganisms can interact so closely, which they can be considered as a metaorganism. Synergic interactions between plant and the microbiome improve the ecosystem's homeostatic response to a number of disturbances and enable effective purification of soil and water, and removal of contaminants. This chapter describes some examples of nature-based solutions (e.g. Plant assisted-bioremediation, constructed wetlands and Plant-microbial fuel cells) that rely on plant and microorganisms as a unique metaorganism. [ABSTRACT FROM AUTHOR]

The purpose of this review article is to present the primary factors that cause clogging of substrate in Constructed wetlands (CWs), as well as the consequences and possible solutions. A wide range of sources, including books, scholarly and internet articles, were used in the literature study. Substrate clogging is a major problem in CWs, which results in slowing down the flow of water and, finally, a significant reduction in the system's treating wastewater effectiveness. The deposition of suspended matter, the development of sludge, precipitation of chemicals and deposition inside the pore spaces, the growth of plant root systems, the production of gas, and the compaction of the clogging layer all contribute to this technical and operational challenge. Evaluating the extent of substrate clogging in CWs is a difficult task because this phenomenon is influenced by several factors. Clogging impact can be assessed using a variety of methods, including tracer testing, hydraulic conductivity measurements, and clogging matter characterization. A preventive or restorative strategy can be used to address this issue. Pre-treatment of wastewater, proper substrate and aquatic plant selection, earlier removal of leaves and dead roots, and backwashing are some of these strategies. [ABSTRACT FROM AUTHOR]

The effectiveness of constructed wetlands (CWs) created to improve water quality has been demonstrated. However, their role in enhancing biodiversity, such as in plankton communities, is still understudied. To assess this, we analysed, over two years, the plankton of three structurally different CWs which are intermediaries between low-quality waters and a protected Mediterranean wetland (Albufera de València Natural Park). We estimated the alpha-diversity of each CW and the beta-diversity among their different sectors. In two CWs, the diversity decreased as water flowed from the Inlet (a species mix from anthropically disturbed environments) to the Outlet, due to natural assembly processes. In the other CW, as it received water dominated by a few species, the emerging assemblages increased the diversity. Moreover, comparing the three CWs, the most divergent communities were those in the outlets (due to the emergence of exclusive species, biovolume differences, etc.). Therefore, they contributed to beta-diversity as they acted as generators of communities, which were characterized by the loss of cyanobacteria and chlorophytes, the dominance of large copepods or cladocerans and the presence of unshared species. We emphasize the importance of having structurally and functionally different CWs to enhance biodiversity and improve biological water quality in natural parks. [ABSTRACT FROM AUTHOR]

Livestock farming wastewater is complex in composition, containing a large number of pathogenic microorganisms and ammonia nitrogen (NH 4 +-N) with high concentration, which makes biological treatment difficult. In this study, tidal flow constructed wetlands were applied to treat piggery biogas slurry. Compared with a continuous flow constructed wetland, two tidal influent modes (hydraulic retention time: idling time for 12 h:12 h and 20 h:4 h, namely TFCW1 and TFCW2) were set up to explore treatment performances on chromaticity, turbidity, chemical oxygen demand (COD), total nitrogen (TN), NH 4 +-N and total phosphorus (TP), and determine the relationship between nitrogen transfer and dissolved oxygen (DO) contents. The fluorescence spectra of dissolved organic matter (DOM) in constructed wetlands were analyzed by excitation-emission matrix spectroscopy-parallel factor analysis to reveal its composition and content of humus. The results showed that tidal flow constructed wetlands obviously improved the removal of chromaticity and turbidity by 44.6% and 10.1%, in comparison to continuous flow constructed wetland. TFCW2 had enhanced reduction on pollutants, with removal efficiencies of COD, NH 4 +-N and TP at 78.6%, 82.1% and 84.0%, respectively. Furthermore, three fluorescent components were detected in TFCW2, and the value of Fmax was increased in the effluent, among which the Fmax of C3 (Humic-like substances) increased obviously from 0.320 to 9.39. The ratio of C2 (Aquatic fulvic acids) to C3 showed a slow increasing trend in the daily outflow of TFCW2, while C1 (dark-incubation substances) remained relatively constant. Fluorescence index (FI), humification index (HIX) and biological index (BIX) increased from 1.35 to 2.09, 0.210–1.51, and 0.240–1.05, respectively, showing that the effluent from the tidal flow constructed wetland had a high microbial activity. This study provided a new insight for the advanced treatment of livestock biogas slurry with a high NH 4 +-N content. [Display omitted] • Actual piggery biogas slurry was treated by tidal flow constructed wetland. • The changes of DO and pollutant concentrations along the system were detected. • 82.1% of NH 4 +-N and 84.0% of TP were removed by tidal flow constructed wetlands. • Dark-incubation substances, aquatic fulvic acids and humic-like substances were three main components in DOM. [ABSTRACT FROM AUTHOR]

Sediments in aquatic systems often act as a major sink for contaminants. Diffusive gradient in thin films (DGTs) and in situ equilibrium dialysis samplers (peepers) are two major in situ pore water sampling devices that overcome the problems associated with conventional pore water sampling methods. In the present study, DGTs and peepers were used to study the spatial and seasonal effects (cool months, October–February; warm months, May–September) on metal bioavailability in the H‐02 constructed wetland and the sink versus source role of the sediments by calculating the metal resupply capacity. Data showed similar seasonal trends in metal concentrations using passive samplers, peepers, and DGTs. Pooled Cu and Zn concentrations measured using DGTs were lower in warm months (1.67 ± 1.50 and 2.62 ± 0.68 μg L–1, respectively, p < 0.001) versus in cool months (2.12 ± 0.65 and 5.58 ± 1.33 μg L–1, respectively, p < 0.001; mean ± 95% confidence interval). Sulfate (SO42−) concentrations were significantly (p = 0.0139) lower in warm months (averaged at 0.22 ± 0.05 mg L–1) compared to in cool months (0.16 ± 0.05 mg L–1). The increase in SO42− concentration is an indicator of the lower activity of sulfate‐reducing bacteria, which need SO42− during anaerobic respiration, in which SO42− is reduced to sulfide (S2–) that forms insoluble salts with Cu and Zn, which could partially explain the higher bioavailability of these metals in the cool season. Metal resupply capacity of the sediments was mostly <0.2 for Cu and Zn. Taken together, the H0‐2 wetland sediments mostly acted as a sink to both Cu and Zn over the course of the present study. Environ Toxicol Chem 2023;42:2726–2736. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Wetlands, as temporary or permanent water reservoirs, provide various benefits for the ecosystem, such as water supply, waste water treatment, and dust control. By the end of 2023, the Iranian government and the Ramsar Convention have registered 25 international and 226 national wetlands. West Azerbaijan and Mazandaran provinces have more wetland ecosystems than any other provinces. Semnan, Yazd, and Zanjan provinces have no wetlands. According to the Ramsar Convention of 1971, Iran has 32 aquatic ecosystems that have the potential to become wetland. In addition, according to the available data and the WHO standard, eight wetlands have the highest probability of producing dust and should be given more attention and care. We recommend the wetland management plan, which ensures their water requirements, protects them from degradation and pollution, and promotes their ecological restoration. Satellite image analysis can help explore how climate change affects dust intensity, considering the role of wetlands in dust control. [ABSTRACT FROM AUTHOR]

This study reports a literature review of the state of the art, 2000-2020, on the substrates that are used as support media in constructed wetlands with subsurface flow. Its importance compared to the most used substrates worldwide and its economic feasibility as a substrate in CW. 13 different types of substrates have been identified in 155 different studies, but the most used substrates were gravel (32%) and sand (23%) for the development of bacterial associations. However, gravel and sand used in full-scale CW are expensive (10–35 $USD/m3), for wastewater treatment in small communities with economic difficulties. The tendency is to use substrates such as gravel (32%), sand (23%), sediments (13%), limestone or river rock (11%), granite (8%), zeolite (6%) and other alternative materials (7%). Among these we can mention: ceramics, pumice, steel, bricks, shells of different local aquatic fauna and some stone materials easily found in the study area. Therefore, the development of substrates of lower commercial value, reused material and material of easy operation is important, especially in developing countries where economic resources are one of the main constraints in the implementation of wastewater treatment systems. The use of treatment wetlands with economic materials detected in this study indicate that the future in wastewater treatment is this technology, because present multiple objectives, which include water treatment, fertilizer production, enhancement of biodiversity and cooling, vegetation production for handicraft, etc. CW are a technology with future role in circular economy that want to respond to sanitation worldwide. [ABSTRACT FROM AUTHOR]

Floating treatment wetlands (FTWs) are a cost-effective ecological engineering tool for the restoration of polluted water bodies. The aims of this work were to evaluate the removal of Cr(III) and Cr(VI) by FTWs using Typha domingensis, and to assess Cr accumulation and distribution in plant tissues and sediment. Treatments were 5 and 10 mg L−1 of Cr(III), and 5 and 10 mg L−1 of Cr(VI), with and without FTWs, and biological control (BC) with FTW without Cr addition. Both Cr species were efficiently removed from water in all treatments (Cr removal > 80%). Cr concentration in sediments of treatment without FTWs was significantly higher than in sediments of treatments with FTWs, indicating that T. domingensis was directly involved in Cr removal. In sediment, Cr was mainly bound to the organic matter in all treatments with a low risk of future release under FTW conditions. T. domingensis demonstrated tolerance to both Cr species at 5 and 10 mg L−1 with Cr accumulated mainly in the roots in all treatments. The use of FTWs planted with T. domingensis is a suitable tool to remediate water bodies contaminated with Cr. This study evaluates the removal efficiency of Cr(III) and Cr(V) in Floating Treatment Wetlands planted with Typha domingensis in greenhouse experiments. Cr accumulation and distribution in plant tissues and different sediment fractions were also assessed [ABSTRACT FROM AUTHOR]

In order to restore degraded wetlands, restoration projects were implemented in the Yellow River Delta wetland reserve from 2010. Water was diverted from the Yellow River and was used to saturate artificial wetlands. This study used in-situ data and model simulations to investigate the effects of water diversion on groundwater systems in the artificial wetlands in 2010, 2011, and 2013. The objectives were to: (1) develop a model for simulating groundwater flow within the study area using Visual MODFLOW, (2) apply the model to simulate and compare the water-table and water-balance responses to water diversion between years, and (3) compare several landscape scenarios that combine artificial shallow ponds and canals and investigate potential water efficiency improvements in the wetland reserve. Results indicate that precipitation infiltration, evapotranspiration, and wetland leakage were the most dominant water budget components. Water diversion increased groundwater storage and shifted the water tables. Between 2010 and 2013, as the water diversion volume in the restoration area near the Diaokou Channel increased, wetland leakage increased, and the spatial effect (meaning impact range on groundwater) of diversion increased from 800 to 1,000 m. Based on the scenario analysis, wetland canals have lower evapotranspiration losses, thus diversion canals that retain water for a longer duration improve the efficiency of water use. Artificial shallow ponds and canals may enhance surface-water/groundwater interactions and restore plant biodiversity. This study can provide a design reference for the construction of artificial wetlands in semiarid areas. [ABSTRACT FROM AUTHOR]

This study addresses a persistent environmental concern related to graywater discharge from households, highlighting its potential to contribute to increased pollution in water bodies. To mitigate this issue, the research explores the use of subsurface flow‐built wetlands, specifically focusing on the innovative application of constructed tidal and vertical flow wetlands (CTWFWs) as wastewater treatment systems. The study not only evaluates the efficacy of these CTWFW systems but also delves into the crucial aspects of their operation and their interactions with the biological, physical, and chemical characteristics of graywater. A key innovation of this research is the investigation of zeolite's effectiveness and the utilization of perlite‐based plant species in both mixed and monoculture configurations to develop lab‐scale hybrid constructed wetlands (HCWs). These HCWs are designed for the removal of organic matter and nutrients from graywater, offering a sustainable and cost‐effective solution to this environmental challenge. The study also examines the dynamic processes involved in graywater treatment, emphasizing how the removal of parameters like biological oxygen demand (BOD), nutrients, total suspended solids (TSS), and disinfection efficiency can significantly impact the effectiveness of treatment systems. Furthermore, the research scrutinizes the intricate relationship between the treatment unit's dimensions and the specific criteria that need to be met for efficient graywater treatment. Intriguingly, the study tracks the changes in graywater composition and the treatment process over time. By conducting on‐site measurements of various physicochemical characteristics such as temperature, dissolved oxygen (DO), electrical conductivity (EC), turbidity, total dissolved solids (TDS), and pH, the research offers a comprehensive understanding of the treatment system's performance and adaptability. The study dives into the microbial communities within the treatment systems, utilizing 16S rRNA amplicon sequencing to characterize the complex microbial ecosystem present in graywater. This approach sheds light on the interplay between microorganisms, physicochemical conditions, plant responses, substrate dynamics, and the production of microbial metabolites. It underscores the holistic nature of the research, encompassing various aspects of graywater treatment. Notably, the study explores the application of biochar in combination with the target heavy metal, cadmium (Cd), within constructed wetlands (CWs). This innovative approach aims to better understand the kinetics and isothermal adsorption of lead in the context of mouthwash residue, expanding the knowledge base in this critical area. The research findings are substantial, with remarkable removal efficiencies achieved for parameters like TSS, turbidity, chemical oxygen demand (COD), nitrate, and phosphate. These results underscore the practicality and effectiveness of the proposed treatment methods. This holistic and pioneering research significantly advances the understanding of sustainable graywater treatment, offering valuable insights and practical solutions to mitigate water pollution concerns. Practitioner Points: This study addresses a persistent environmental concern related to greywater discharge from households, highlighting its potential to contribute to increased pollution in water bodies.The study not only evaluates the efficacy of these CTWFW systems but also delves into the crucial aspects of their operation and their interactions with the biological, physical, and chemical characteristics of greywater.A key innovation of this research is the investigation of zeolite's effectiveness and the utilization of perlite‐based plant species in both mixed and monoculture configurations to develop lab‐scale hybrid constructed wetlands (HCWs). [ABSTRACT FROM AUTHOR]

The Classic Maya (c. 250 to 900 CE) in the tropical southern lowlands of Central America dealt with water scarcity during annual dry seasons and periods of climate instability via sophisticated urban reservoir systems they relied on for over a thousand years. Surface water is limited because typically rain percolates through the karstic terrain. I posit that Maya reservoirs functioned as do constructed wetlands (CWs) at present. Still-water systems like CWs and Maya reservoirs can become stagnant and nonpotable due to the build-up of nutrients that promote algal growth. Stagnant waters also serve as breeding grounds for mosquitoes that spread endemic diseases. CWs keep water clean via certain aquatic plants since all plants uptake nutrients (e.g., nitrogen, phosphorus) and decomposing plant matter supports microbial biofilms that break down nutrients. CWs also support diverse zooplankton that prey on pathogens and bacteria that assist to denitrify water. CWs do not require the use of chemicals or fossil fuels and after the initial labor-intensive output become self-cleaning and self-sufficient with some maintenance. I posit that the Maya used a diverse array of aquatic plants and other biota to keep water clean in the same manner as do CWs, which I demonstrate using evidence from excavations and settlement maps, sediment cores and current wetlands, and the iconographic and hieroglyphic records. The next step is to combine what we know about ancient Maya reservoirs in conjunction with what is currently known about CWs to better address future water needs. [ABSTRACT FROM AUTHOR]

The wetland species showed strong associations with the nature reserves protecting the Yellow River wetlands in Henan Province. Three review articles were gathered in the first part of the Special Issue, presenting an introduction to the topic with a review of wetlands' most typical species; a review of one of the adaptations to these specific abiotic conditions; and another review showing proof that wetlands host a great number of threatened species, making another argument for preserving these ecosystems. Inland wetlands are one of the most vulnerable ecosystems on Earth and have one of the highest rates of decline in surface and biodiversity. Most orchid taxa grow in the following wetland vegetation types: wet meadows (especially in order Molinietalia caeruleae); fens (in order Caricetalia fuscae); tall-herb vegetation along mountain streams and springs; and marshes and herbaceous vegetation of freshwater or brackish water bodies. [Extracted from the article]

Constructed wetland helps to improve the environmental and social values of the inhabited catchments and their downstream natural water bodies. However, the environmental impacts due to its construction necessitate evidence of how beneficial it would be once operational compared to other water-sensitive urban design (WSUD) components. The study has simulated the reduction of pollutants and runoff in a wetland. Consequently, environmental impacts were estimated using the life cycle assessment (LCA) approach. The catchment settings with and without wetlands were compared with the environmentally viable rainwater harvesting (RWH) systems. Potable supply using watermain was included in the catchment settings to have a common basis for their evaluation, which was not considered in the existing literature. The study demonstrates that the runoff impacts (operational) of the catchment having a watermain (without a wetland system) are 3.6–4.5, 4.0, 3.2–4.7, and 2.7–3.5 times of catchment with wetland-only on ecotoxicity-marine, ecotoxicity-freshwater, human toxicity-carcinogenic, and eutrophication categories. For the same systems, the net impacts (fabrication & installation + operational) of all undertaken impact categories are 3–28.6 times. In contrast, the net impacts of the residual runoff generated by the most viable RWH systems after supplying household demands (i.e., % reliability of the RWH tanks) are mostly 2.3–30.5 times the net impacts of the catchment having wetland-only. In an equivalent assessment, the catchment net impacts of the watermain system (with wetland) as times of impacts of RWH systems are 0.2–0.91 times on eutrophication, ozone depletion, ecotoxicity-marine (in lower series of RWH), and ecotoxicity-freshwater. In contrast, those systems are mostly 1.02–3.12 times on human toxicity-carcinogenic, global warming, ecotoxicity-terrestrial and higher series of ecotoxicity-marine impact categories. The study suggests that wetland or RWH is suitable if emission prevention to water or air is emphasized. [ABSTRACT FROM AUTHOR]

Tequila vinasse has a high contaminating capacity due to its physicochemical characteristics. Efficient and low-cost alternative treatments are required to reduce and control the environmental impacts caused by raw vinasse discharges, mainly from micro and small factories. One option is wetland technologies in which vegetation plays an important role in the proper functioning of the system; thus, the species to be used must be properly selected based on their resistance and tolerance to the toxic effects of vinasse. Therefore, this study aims to evaluate the resistance of four macrophyte species to tequila vinasse in wetland microcosms that is, Canna indica, Cyperus papyrus, Iris sibirica, and Typha latifolia which were exposed to 5, 7, 10, 12, and 15% of vinasse diluted with domestic wastewater. The control parameters (relative content, evapotranspiration, pH, electrical conductivity, and apparent color) showed that the plants in general developed stress symptoms. However, statistical analysis revealed a significant difference (p < 0.05) between plant species and vinasse treatments, further evidencing that I. sibirica is the species with the greatest potential to be used as emergent vegetation in treatment wetlands for the purification of tequila vinasse. The novelty of this study lies in the fact that different species of macrophytes have been evaluated to find those with the capacity to resist the physicochemical characteristics of tequila vinasses; corroborating that there are more appropriate species than others. I. sibirica stood out mainly based on its better physiological response to the Relative Chlorophyll Content, which is the most important parameter for the evaluation of plant health. In this way, the results of this study will allow the evaluation of different types of constructed wetlands for the treatment of tequila vinasse. The knowledge generated is useful for treating other distillery stillages around the world with wetland technology. [ABSTRACT FROM AUTHOR]

Aim: Artificial island habitats such as human‐made wetlands are emerging novel ecosystems. Understanding the drivers of diversity in such artificial systems is essential for balancing the goals of biodiversity conservation and human socio‐economic needs. Location: Telangana state, India. Methods: We surveyed water birds in a network of 57 artificial wetlands and assessed four macroecological biodiversity patterns: spatial betadiversity, temporal betadiversity, species‐abundance distributions (SADs), and the species–area relationship (SAR). We employed a mix of phenomenological and mechanistic models to examine the four macroecological patterns. We hypothesized that the wetland bird communities are primarily structured by immigration–extinction dynamics and thus that spatial and temporal betadiversity would be high, the within‐wetland SADs would exhibit a large number of rare species and a monotonically declining overall shape, and that the SAR across wetlands would be strongly increasing. Results: Spatial and temporal betadiversity were both high and mostly attributable to turnover rather than nestedness. While the pooled SAD exhibited an interior mode, the SAD for individual wetlands was generally log‐series distributed, consistent with a model in which immigration among wetlands is high. The SAR exhibited an increasing trend, with the 'small‐island effect', which reflects constraints on immigration and is often observed for true island archipelagos, being absent. Main Conclusions: We tentatively conclude that bird diversity in this network of artificial wetlands is mainly structured by immigration–extinction dynamics, although we acknowledge that some of the patterns are also consistent with niche dynamics and future research should measure relevant biotic and abiotic variables in these wetlands. We encourage future work in which our rich dataset is used to fit dynamic models that permit more‐detailed quantitative inferences about mechanisms structuring diversity in this novel ecosystem, which can ultimately also inform conservation management. [ABSTRACT FROM AUTHOR]

Landscape modifications often undermine habitat suitability for species' persistence, with initial effects observed through the physiological responses of individuals and populations. However, some landscape features can allow tolerant wildlife species to persist in human‐modified landscapes, but they are still overlooked. Across distinct agricultural landscapes, we assessed landscape features affecting the body condition (estimate through scaled mass index ‐ SMI) of Caiman crocodilus (Crocodylia, Alligatoridae) in human‐modified landscapes of the Araguaia floodplain, central Brazil. We used a spatial Bayesian model averaging approach to determine the effects of landscape attributes, ectoparasites, tail damage and severe body injuries on caiman body condition. We found that caimans had higher SMI in anthropogenic (ditches and artificial ponds) than natural habitats (lakes or rivers). Overall, caiman SMI was negatively associated with wetland cohesion (an aggregation and connectivity metric). Otherwise, landscape composition did not influence caiman SMI. Further, ectoparasites and body injuries did not affect SMI, whereas tail damage negatively affected SMI. Our findings underscore that caiman populations can adapt to artificial wetlands and irrigated rice fields, provided they incorporate natural and semi‐natural habitat patches that enhance environmental heterogeneity, prey availability, and waterbody availability and connectivity. [ABSTRACT FROM AUTHOR]

Constructed wetlands are commonly utilized to treat industrial wastewater due to their effectiveness, affordability, and environmental benefits. Many phosphorus chemical enterprises in the middle Yangtze River basin are facing high pollution load challenges and efforts are needed to improve removal efficiency of pollutants. This work was the first to use constructed wetlands for phosphorus chemical industry tailwater (PCITW) treatment. The new hybrid constructed wetlands (CWs) proposed were the aeration horizontal subsurface flow constructed wetland (AHSCW) and the integrated vertical flow constructed wetland (IVCW), which were constructed on a pilot scale. Here, the effectiveness of pollutant removal along hybrid CWs, wetland plant growth, and rootassociated microbial community responses to the PCITW were investigated. The results showed that there was spatial variation in removal of carbon, nitrogen, and phosphorus in the hybrid CWs, and that the AHSCW and the IVCW played synergistic roles in the removal of pollutants. Compared with influent, the toxic effect of effluent to embryos of a rare minnow (Gobiocypris rarus) was alleviated. Exposure to the effluent resulted in no malformation or death for embryos. Plants and microorganisms in the wetland system of the phosphate chemical tailwater were then compared with the control system of municipal tailwater. Plants in the former system had lower root density, and higher average root diameter, root shoot ratio, specific root length, and specific surface area. Plant roots also had decreased NH4 þ uptake ability but increased Ca2þ uptake to adapt to the high load and complex pollution stress. Unlike the control system, stochastic mechanisms had a more important role than deterministic processes in shaping the microbial community assembly associated with the PCITW. Meanwhile, analysis of microbial network-level topological characteristics demonstrated substantial reduction in network interactions complexity and microbiome stability in the treatment system. Findings from this study suggest wetlands will be helpful for efficient purification of phosphorus chemical industry wastewater in the Yangtze River basin. [ABSTRACT FROM AUTHOR]

In recent years, the emergence of COVID-19 has created disastrous health effects worldwide. Doxycycline, a member of the tetracycline group, has been prescribed as a treatment companion for attending this catastrophe. Due to extensive use and high solubility, a significant amount of un-metabolized doxycycline has been found to reach water bodies within a short time, and consumption of this water may lead to the development of fatal resistance in organisms and create health problems. Therefore, it has become necessary to develop suitable technologies from a geoenvironmental point of view to remove these unwanted antibiotics from wastewater. In this context, locally obtainable silty-sandy soil was explored as a low-cost material in a constructed wetland with Chrysopogon zizanioides (vetiver sp.) for phytoremediation to mitigate doxycycline spiked wastewater. The obtained soil hydraulic conductivity was 1.63×10−7 m/s. Batch adsorption tests conducted on silty-sandy soil, vetiver leaf, and vetiver root provided maximum removal efficiencies of 90%, 72%, and 80% percent, respectively, at optimal sorbent doses of 10 g/L , 17 g/L , and 16 g/L , and contaminant concentrations of 25 mg/L , 20 mg/L , and 23 mg/L , with a 30-min time of contact. The Freundlich isotherm was the best fit, indicative of sufficient sorption capacity of all the adsorbents for doxycycline. The best match in the kinetic research was pseudo-second-order kinetics. A one dimensional vertical column test with the used soil on doxycycline revealed a 90% breakthrough in 24 h for a soil depth of 30 mm. Studies on a laboratory-scale wetland and numerically modeled yielded removal of around 92% by the selected soil and about 98% combined with Chrysopogon zizanioides for 25 mg/L of initial doxycycline concentration, which is considered quite satisfactory. Simulated results matched the laboratory tests very well. The study is expected to provide insight into remedies for similar practical problems. To explore a cost-effective method for abatement of aqueous doxycycline in the surrounding environment and groundwater, a locally accessible silty-sandy soil was selected. While investigating its suitability, it was found that this soil met current standards (10−4 to 10−5 cm/s) for hydraulic conductivity of wetland adsorbent. The selected soil also had a relatively large surface area (23.502 m2/g), and the presence of higher percentages of finer particles (50%) resulted in an outstanding adsorptive and removal capacity for doxycycline, as indicated by several test findings and validated with numerical modeling. Furthermore, as evidenced by batch experiments, the vegetative cover, primarily provided by vetiver, was also found to be an effective adsorbent. Sorption of a particular contaminant in wastewater to wetland soil is problematic due to the simultaneous presence of various compounds and other wastewater contaminants. The competition effect among these compounds is of concern in any treatment wetland, where thousands of compounds are present. Hence, further studies are required to address the competition between these compounds and their cumulative effect on the efficacy of the wetland system over a long period. This has therefore cemented the fact that silty-sandy soil is a perfect choice as bed material for wetlands. Together with vetiver, it has the potential to become a stable and environment-friendly removal system against doxycycline. However, the investigation was carried out with a spiked doxycycline solution in the laboratory, the results of which are believed to provide a basic understanding and remedial measures for this problem. Based on that, if several field studies are conducted with the studied soil using phytoremediating plants in doxycycline-laden wastewater, a real-life solution to the doxycycline problem may be obtained that is very much needed for assuage of social health problems. [ABSTRACT FROM AUTHOR]

Most of the previous studies exploring the changing patterns of wetland in the Yellow River Delta (YRD) were conducted based on sparse time-series images, which ignored its severe environmental gradient and rapid evolution process of the wetland. The changes in the dominant factors in the evolution of the wetland in the YRD are not clear. This study used the dense time-series Sentinel-2 images to establish a wetland database of the YRD, and then analyzed the spatial distribution characteristics of, and temporal changes in, the wetland during 2015–2022. Finally, the dominant factors of the spatio-temporal evolutions of the wetland were explored and revealed. The results showed the following. (1) During 2015–2022, the wetland in the YRD was dominated by artificial wetland, accounting for 54.02% of the total wetland area in the study area. In 2015–2022, the total wetland area increased by 309.90 km2, including an increase of 222.63 km2 in natural wetlands and 87.27 km2 in artificial wetlands. In the conversion between wetland types, 218.73 km2 of artificial wetlands were converted into natural wetlands, and 75.18 km2 of natural wetlands were converted into artificial wetlands. The patch density of rivers, swamps, and salt pans increased, showing a trend of fragmentation. However, the overall degree of landscape fragmentation in wetlands weakened. The trend of changes in the number of patches and landscape shape index was the same, while the trend of changes in Shannon's diversity index and Contagion index was completely opposite. (2) Natural factors, such as precipitation (0.51, 2015; 0.65, 2016), DEM (0.57, 2017; 0.47, 2018; 0.49, 2020; 0.46, 2021), vegetation coverage (0.59, 2019), and temperature (0.48, 2022), were the dominant influencing factors of wetland changes in the YRD. The dominant single factor causing the changes in artificial wetlands was vegetation coverage, while socio-economic factors had lower explanatory power, with the average q value of 0.18. (3) During 2015–2022, the interactions between the natural and artificial factors of the wetland changes were mostly nonlinear and showed double-factor enhancement. The interactions between temperature and sunshine hours had the largest explanatory power for natural wetland change, while interactions between precipitation and vegetation coverage, and between temperature and vegetation coverage, had large contribution rates for artificial wetland change. The interactions among natural factors had the greatest impacts on wetland change, followed by interactions between natural factors and socio-economic factors, while interactions among socio-economic factors had more slight impacts on wetland change. The results can provide a scientific basis for regional wetland protection and management. [ABSTRACT FROM AUTHOR]

Antibiotics, their transformation products, and the translocation of antibiotic-resistant genes in the environment pose significant health risks to humans, animals, and ecosystems, aligning with the One Health concept. Constructed wetlands hold substantial yet underutilized potential for treating wastewater from agricultural, domestic sewage, or contaminated effluents from wastewater treatment plants, with the goal of eliminating antibiotics. However, the comprehensive understanding of the distribution, persistence, and dissipation processes of antibiotics within constructed wetlands remains largely unexplored. In this context, we provide an overview of the current application of stable isotope analysis at natural abundance to antibiotics. We explore the opportunities of an advanced multiple stable isotope approach, where isotope concepts could be effectively applied to examine the fate of antibiotics in wetlands. The development of a conceptual framework to study antibiotics in wetlands using multi-element stable isotopes introduces a new paradigm, offering enhanced insights into the identification and quantification of natural attenuation of antibiotics within wetland systems. This perspective has the potential to inspire the general public, governmental bodies, and the broader research community, fostering an emphasis on the utilization of stable isotope analysis for studying antibiotics and other emerging micropollutants in wetland systems. [ABSTRACT FROM AUTHOR]

Constructed wetlands are viable alternatives for the removal of multiple pollutants. The performance of Sagittaria latifolia in free flowing and subsurface wetlands in removing pollutants from domestic waters was evaluated. 12 wetlands will be followed, three free with species and three without species, three subsurface with species and three without species, with retention times of 6.7 days for the free and 3.5 days for the subsurface. The subsurface with species presented an effluent with turbidity of 4.4±0.8 NTU, color of 143.9±27.4 UC and 33.9±25.7 mgL-1 of COD. The free samples with species presented turbidity of 10.1±2.8 NTU, color of 346.3±87.0 UC and 74.7±30.0 mgL-1 of COD. The wetland with the best performance was the subsurface with species, eliminating turbidity, color, and COD in 95.9, 89.4, 95.7% respectively, obtaining a COD kinetic coefficient of 0.34 (free flow) and 0.89 days-1 (subsurface). [ABSTRACT FROM AUTHOR]

Macrophyte rhizosphere microbes, as crucial components of the wetland ecosystem, play an important role in maintaining the function and stability of natural and constructed wetlands. Distinct environmental conditions and management practices between natural and constructed wetlands would affect macrophytes rhizosphere microbial communities and their associated functions. Nevertheless, the understanding of the diversity, composition, and co-occurrence patterns of the rhizosphere bacterial communities in natural and constructed wetlands remains unclear. Here, we used 16S rRNA gene high-throughput sequencing to characterize the bacterial community of the rhizosphere and bulk sediments of macrophyte Phragmites australis in representative natural and constructed wetlands. We observed higher alpha diversity of the bacterial community in the constructed wetland than that of the natural wetland. Additionally, the similarity of bacterial community composition between rhizosphere and bulk sediments in the constructed wetland was increased compared to that of the natural wetland. We also found that plants recruit specific taxa with adaptive functions in the rhizosphere of different wetland types. Rhizosphere samples of the natural wetland significantly enriched the functional bacterial groups that mainly related to nutrient cycling and plant-growth-promoting, while those of the constructed wetland-enriched bacterial taxa with potentials for biodegradation. Co-occurrence network analysis showed that the interactions among rhizosphere bacterial taxa in the constructed wetland were more complex than those of the natural wetland. This study broadens our understanding of the distinct selection processes of the macrophytes rhizosphere-associated microbes and the co-occurrence network patterns in different wetland types. Furthermore, our findings emphasize the importance of plant–microbe interactions in wetlands and further suggest P. australis rhizosphere enriched diverse functional bacteria that might enhance the wetland performance through biodegradation, nutrient cycling, and supporting plant growth. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the efficacy of using the constructed wetland for purification of secondary effluent from a wastewater treatment plant (WWTP) in the eastern district of Anyang, Henan province, China. A Subsurface Flow Constructed Wetland (SSFCW) system was designed and constructed, consisting of 302 SSFCW units (L×W×H = 30×20×1.4 m for each unit) with a treatment capacity of 105 m3/d. Each unit of the system was planted with equal number of Phragmites australis, Typha orientalis Presl, and Zizania latifolia at the density of 16 plants/m2. The average values of the Chemical Oxygen Demand (CODCr), Biochemical Oxygen Demand (BOD5), Ammonia Nitrogen (NH3-N), and Total Phosphorus (TP) of the effluent sampled from 4 outlets of the system chosen at random for 17 months consistently met the Class III of Environmental quality standard for surface water in China, even during the cold season. According to the economic analysis, the system may generate an annual profit of around ¥ 1.4 million yuan. The SSFCW system is an cost-effective and profitable technique for the further polish of the secondary effluent from the wastewater treatment plant. [ABSTRACT FROM AUTHOR]

Surface coal extraction and subsequent reclamation activities alter habitat availability for Appalachian wildlife, although broad surveys of mine-associated taxa are still largely lacking from the Virginia coalfields. We utilized game cameras to survey the mammal diversity of three habitat types - mined and reclaimed scrub/shrub habitat, mined and reclaimed scrub/shrub habitat associated with constructed wetlands, and unmined reference forests - at a reclaimed surface mine in Wise County, Virginia. We encountered 14 mammal species at this site, with the highest mammal diversity at mined wetlands and in unmined reference forests. Mammal diversity was substantially lower on reclaimed upland scrub-shrub habitats, echoing past findings for other taxa regarding decreased wildlife diversity on former surface mines. Our data provide a preliminary comparison of mammal diversity across three habitats associated with a former surface mine in the Virginia coalfields and highlight several key recommendations for land managers charged with maintaining wildlife diversity on formerly mined sites. [ABSTRACT FROM AUTHOR]

The Duwamish River Floating Wetlands project designed, built, and deployed constructed floating wetlands in the estuary of the urban Duwamish River in Seattle, Washington, during the 2019 and 2020 outmigration seasons for juvenile salmon. Using a "safe‐to‐fail" methodology and adaptive management strategies, these innovative floating wetland prototypes were custom designed to provide the native plants, invertebrates and slow water habitat that juvenile salmon require during their transition from fresh to salt water, and were monitored for these outcomes. This paper will provide insight into the prototype designs, adaptive management strategies and plant performance, and unique public‐private‐academic‐community partnerships that supported 2 years of design and research. [ABSTRACT FROM AUTHOR]

Understanding the controls on uranium (U) mobility in the environment is key to improve the management of sites contaminated by U mining activities. Previous research has shown that natural or engineered wetlands are particularly able to scavenge high amounts of U(VI) and U(IV) under noncrystalline forms. However, questions remain on the respective roles of sorption and reduction processes in the removal of U from running waters in wetlands, as well as on the long-term stability of U storage. Here, we performed a series of geochemical, isotopic (δ238U, (234U/238U)), microscopic (SEM-EDXS, EPMA) and spectroscopic (µ-XRF, µ-XAS, XANES and EXAFS at the U L 3 and M 4 -edges and Fe K -edge) investigations to determine the modes of U accumulation and assess U mobility in a natural exceptionally U-enriched (up to 5000 µg/g) wetland on the shore of Lake Nègre (Mediterranean Alps, France). Uranium (VI) was largely dominant in the two studied soil cores, except a few samples containing as much as ∼50 % U(IV). At the particle scale, U is associated to a variety of organic constituents of the soil matrix with a homogenous oxidation state. Bulk EXAFS spectroscopy at the U L 3 -edge shows that U is mostly mononuclear, with dominant monodentate binding to organic moieties (C neighbors at ∼3.45 Å). An additional minor fraction of U under polymeric forms is inferred from wavelet (CCWT) analysis of the EXAFS data. These observations are reinforced by 1 M bicarbonate extractions that result in the dissolution of 82–96 % of total U, including putative polymeric species. At the wetland scale, similar or slightly fractionated isotopic ratios (δ238U) between the wetland-feeding creek waters and the wetland soils are observed, supporting the idea that U(VI) sorption on organic matter is the primary U scavenging mechanism. Furthermore, it indicates that partial U(VI) reduction to U(IV) occurs as a second step, after sorption. Analysis of U decay chain disequilibria in the cores as a function of depth suggests that U accumulation in this wetland has lasted for several thousand years. We propose that the wetland acts as an active reactor where U has been massively accumulating for ∼14500 years, especially as U(VI) forms associated to organic matter, and is further partly exported to the lake through soil erosion. [ABSTRACT FROM AUTHOR]

The worldwide loss of coastal wetlands has traditionally been addressed as the loss of ongoing nutrient retention ecosystem services. However, nutrient remineralization from eroded particles may further exacerbate water quality degradation. Using data on nutrient burial and denitrification from northern Chesapeake Bay, along with estimates of the bioavailability of eroded marsh particulates, the changing role of wetlands as an important sink for nutrients is examined. Although the erosion of wetlands results in the reintroduction of nitrogen and phosphorus into open‐water habitats, the potential for exacerbating eutrophication is highly diminished by the low lability of wetland organic matter. The impact of such erosion on the cycling of Fe‐bound phosphorus from marsh soils is highly dependent on both the amount of inorganic P, its solid phase association with Fe, and its potential remobilization from the estuarine sediments into which it is deposited. Although nutrient sequestration in newly constructed wetlands built from dredged materials suggested a rapid development of nutrient sequestration, a better understanding of nutrient ecosystem services provided by marshes created by transgression into uplands is necessary for understanding the long‐term nutrient retention value of coastal wetlands. [ABSTRACT FROM AUTHOR]

Aquatic environments are hot spots of nitrogen (N) cycling and nitrous oxide (N2O) emission. Understanding key N biogeochemical processes and N2O dynamics is critical for uncovering the responses of aquatic environments to human activities. In this study, we summarized the development of techniques and approaches for determination of N cycling processes and N2O sources in aquatic environments of China. We also reviewed the main N transformation processes and associated biogeochemical controls in aquatic environments of China (e.g., constructed wetlands, paddy fields, lakes, rivers, aquaculture ponds, and estuaries and coasts). In addition, we further synthesized N2O dynamics in these aquatic environments. The results suggested that N cycling processes have been greatly concerned in various aquatic environments of China, whereas more comprehensive analyses of N cycling processes are still sparse for projecting N fates and dynamics in response to changing environments, largely limiting the implementation of N management strategy of China. Aquatic environments of China may be the important sources of atmospheric N2O, but the production and consumption processes of N2O need to be further studied for effective greenhouse gas mitigation. We also argued that it is urgently necessary to incorporate microbial traits into biogeochemical ecosystem modeling to improve the estimation reliability of N cycling and N2O dynamics. This review highlights the importance of N cycling and N2O dynamics, as well as associated environmental implications, and presents the directions of future research on N cycling in aquatic environments of China. [ABSTRACT FROM AUTHOR]

Processing uranium ores into transportable oxide powders produces a stream of wastewaters high in metals, acids, and predominantly nitrogenous nutrients. Conventional water treatment can remove metal ions and buffer acids, but nutrient removal is problematic as it entails both oxidative and reductive steps. Engineered wetlands can achieve nutrient removal by a process of biopolishing, i.e. employing metabolic characteristics of the natural wetland microbiota to carry out the oxidative and reductive steps in series. In this study, we report on the hydraulic characteristics, dissolved oxygen (DO) dynamics, and vegetation of the Corridor Creek Wetland Filter (CCWF) at the Ranger Uranium Mine. Breakthrough curve analysis of dual-tracer test data showed the CCWF to be a highly dispersive wetland system with a dispersion coefficient ≥ ≈ 10,000 m2 d−1. The times for 95% of the tracer to pass through the individual wetland cells were 2–3 times the corresponding cell residence times. DO concentration data suggests that anaerobic conditions are unlikely to occur in the water column. Macrophyte cover in the six cells ranged from 15 to 95% of the cell area and contained 47–96 kg of nitrogen: this compares to an anticipated nitrogen load of 60 kg d−1 from the water treatment plant. Our study demonstrated that the CCWF is a complex physical, hydraulic, and biogeochemical system. Operational conditions required consideration of varying, rather than constant, wetland flow conditions in the breakthrough curve analysis used to quantify the dispersivity of the wetland cells. Water column DO dynamics indicated limited scope for denitrification. The high variability of macrophyte and microbial biomass constrained access to parts of the CCWF, largely limiting measurements to the open water regions. Therefore, rather than attempt quantitative biogeochemical modelling of wetland performance, our study focussed on identifying and understanding key processes in the CCWF. Comparable studies of wetland filters may encounter similar challenges in process quantification. [ABSTRACT FROM AUTHOR]

Mine drainage from the St Louis Tunnel (located at the Rico-Argentine Site) is circumneutral most of the year, with spring freshets increasing flow, decreasing pH and increasing metals concentrations. This study was designed to test the performance of a demonstration-scale horizontal wetlands passive treatment train, comprised of a settling basin, surface flow wetland, horizontal-flow anaerobic wetland, aeration channel, and rock drain, during two years of influent water chemistry at a constant 113 L/min (30 gpm) flow rate. Total Zn, Cd, and Mn effluent concentrations met project treatment goals (PTGs) 75, 96.9, and 100% of the time, respectively, and 93.9, 100, and 100% of the time for the dissolved metals. Most PTG exceedances occurred during the freshet events. Most Zn and Cd attenuation was attributed to sulfide precipitation in the anaerobic cell and capture/filtration of suspended ZnS particles in the anaerobic wetland and rock drain. Manganese was attenuated in the aerobic portion of the anaerobic cell (influent transition zone) as Mn oxides and carbonates. Oxidation of Mn occurred in the rock drain as biogenically formed Mn oxides adhered to the rock matrix. Carryover of dissolved sulfides from the anaerobic cell limited the rock drain's Mn removal efficiency. Low temperatures did not significantly affect biological activity within the system; the effects of seasonal water quality were more important. [ABSTRACT FROM AUTHOR]

Aim: Natural wetlands are widely considered important for mitigation of climate change, but they have been impacted by land use and land cover change (LULCC), often resulting in ecosystem degradation and significant changes in soil carbon (C) and nitrogen (N) dynamics. However, the impact of various LULCC types on wetland soil C and N dynamics remains unclear. Location: Global. Time period: 1982–2021. Major taxa studied: Wetland. Methods: We present a global meta‐analysis using a database of 487 sites compiled from the literature, demonstrating the response of soil C and N concentrations and stocks in coastal wetlands, riparian wetlands and peatlands to various types of LULCCs, including agricultural lands, drained wetlands, aquaculture ponds, pastures and constructed wetlands. Results: The conversion of coastal wetlands, riparian wetlands and peatlands to most LULCC types decreased the mean soil C and N concentrations and stocks by 17.8 ± 10.3, 25.3 ± 13.4 and 23.2 ± 6.3%, respectively. The loss of wetland soil C owing to LULCC is estimated to cause a potential CO2 emission of 1.8–22.8 Mg CO2 equivalent emission/ha/year, except for conversion to constructed wetlands. The soil C and N contents were more sensitive to LULCCs, relative to the stocks. We also found that the patterns of soil C and N variations were closely related to the conversion time since completion of LULCC. After LULCC, the response of soil C and N variables was sensitive to changes in plant biomass, soil water conditions, bulk density, pH and NH4+‐N concentration, with the major controlling factors varying with the conversion age. Main conclusions: Our results highlight the important role of LULCC in triggering soil C and N loss in natural wetlands, which enhances the greenhouse effect. As such, our study calls for sustainable land management strategies aiming at wetland conservation as a powerful tool to mitigate climate warming. [ABSTRACT FROM AUTHOR]

The H-02 constructed wetland was designed to remove metals (primarily copper and zinc) to treat building process water and storm water runoff from multiple sources associated with the Tritium Facility at the DOE-Savannah River Site, Aiken, SC. The concentration of Cu and Zn in the sediments has increased over the lifetime of the wetland and is a concern. A bioremediation option was investigated at the laboratory scale utilizing a newly isolated bacterium of the copper metabolizing genus Cupriavidus isolated from Tim's Branch Creek, a second-order stream that eventually serves as a tributary to the Savannah River, contaminated with uranium and other metals including copper, nickel, and mercury. Cupriavidus basilensis SRS is a rod-shaped, gram-negative bacterium which has been shown to have predatory tendencies. The isolate displayed resistance to the antibiotics ofloxacin, tetracycline, ciprofloxacin, select fungi, as well as Cu2+ and Zn2+. Subsequent ribosomal sequencing demonstrated a 100% confidence for placement in the genus Cupriavidus and a 99.014% match to the C. basilensis type strain. When H-02 wetland samples were inoculated with Cupriavidus basilensis SRS samples showed significant (p < 0.05) decrease in Cu2+ concentrations and variability in Zn2+ concentrations. Over the 72-h incubation there were no significant changes in the inoculate densities (106–108 cells/ML) indicating Cupriavidus basilensis SRS resiliency in this environment. This research expands our understanding of the Cupriavidus genus and demonstrates the potential for Cupriavidus basilensis SRS to bioremediate sites impacted with heavy metals, most notably copper. [ABSTRACT FROM AUTHOR]

There were significant differences in the dominant driving factors of the change process of different types of wetlands in the Yellow River delta. In addition, to our knowledge, the optimal classification feature sets with the Random Forest algorithm for wetlands in the Yellow River delta were least explored. In this paper, the wetland information in the study area was extracted based on a Random Forest algorithm with de-feature variable redundancy, and then the change process of wetland and its dominant factors from 2015 to 2021 was monitored and analyzed using the Geodetector and gravity center model. The results showed that (1) the optimal variable sets composed of red edge indexes based on the Random Forest algorithm had the highest classification accuracy, with the overall accuracy and Kappa coefficient of 95.75% and 0.93. (2) During 2015–2021, a large area of natural wetland in the Yellow River delta was transformed into an artificial wetland. The wetlands showed an overall development direction of "northwest–southeast" along the Yellow River. (3) The interaction between vegetation coverage and accumulated temperature had the largest explanatory power of the change in the natural wetland area. The interaction between solar radiation and DEM had the largest explanatory power for the change in the artificial wetland area. The research results could better provide decisions for wetland protection and restoration in the Yellow River delta. [ABSTRACT FROM AUTHOR]

This article reviews investigations in which Canna indica was utilized in constructed wetlands (CW) for wastewater treatment of a variety types. It is strongly urged that ornamental flowering plants be used in CWs as monoculture or mixed species to improve the appearance of CWs whilst still treating wastewater. Plants play important roles in CWs by giving the conditions for physical filtration of wastewater, a large specific surface area for microbial growth, and a source of carbohydrates for bacteria. They absorb nutrients and integrate them into plant tissues. They release oxygen into the substrate, establishing a zone in which aerobic microorganisms can thrive and chemical oxidation can occur. They also provide wildlife habitat and make wastewater treatment system more visually attractive. The selection of plant species for CW is an important aspect during the CW design process. Canna indica's effectiveness in CWs has shown encouraging results for eliminating contaminants from wastewater. There is still a scarcity of information on the mechanisms involved in removal of specific contaminants such as pharmaceuticals, personal care products, hormones, pesticides and steroids and their potential toxicity to the plants. Therefore, this paper reviews some published information about the performance of Canna indica in wastewater treatment, as well as potential areas for future research. [ABSTRACT FROM AUTHOR]

This study is concerned with the physical impacts of flood-mitigation structures on 'humanised' and 'natural' floodplain ecosystems. The former constitute fertile, well drained and developed surfaces. The latter are mainly degraded wetland areas located in the backwater zones of wide, low-lying floodplains. Three rivers are investigated: the Hawkesbury–Nepean and the Macleay Rivers in New South Wales, Australia and the Durance River in southern France. Their floodplains, flood-mitigation works and floodplain ecosystems are analysed, together with site- and time-dependent differences in their floodplains, their exploitation and their degradation. Conservation of floodplains seeks to reverse wetland degradation, and to increase biodiversity and sustainability, as well as preserving developed floodplains. This study discusses gaps in our biophysical knowledge of ecosystems and the absence of ecological indicators of degradation. It also considers the lack of data on socio-economic values for what are unique, site- and time-specific, biophysical systems. Only when such inadequacies are addressed will the values of ecosystems be fully understood. Then cost-effective management might be possible. These knowledge gaps contribute to the many problems of floodplain management, which are likely to increase when the additional impacts of population increase and global warming become apparent. [ABSTRACT FROM AUTHOR]

In this research, we study a dynamical system of total nitrogen transformation in a mangrove-filled constructed wetland. The system's variables are the mangrove biomass concentration and total nitrogen concentration in wastewater and in soil solution. We investigate the system's dynamics by examining the local stability of the equilibriums, simulating the phase portrait and solutions and providing time-dependent parameter sensitivity analyses. The analysis shows that the level of garbage acts as the parameter for when mangrove biomass will disappear. Both the graphs of the system solutions and the sensitivity function in the case of biomass concentration and total nitrogen concentration in soil solution versus time show symmetrical features at specific time intervals. According to the sensitivity index when reaching equilibrium, the level of garbage is the most sensitive parameter to the system. In addition, we explore the model's discrete form by investigating the conditions for the equilibrium's local stability and presenting bifurcation diagrams for each parameter. The symmetrical aspects are visible in the visualization of the bifurcation diagram and the solutions' chaotic behavior. [ABSTRACT FROM AUTHOR]