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Pilot‐scale surface‐flow, subsurface‐flow and floating aquatic plant constructed wetland system designs were installed and evaluated to determine the effectiveness of constructed wetlands to immobilize and remove metals such as cadmium, zinc, copper, chromium, lead and nickel in tertiary effluent wastewater in a Midwestern US climate (central Illinois). Following wetland treatment, average concentrations of copper decreased from 56.6μg/l in influent to 7.9μg/l (86.0 per cent reduction) in the FAP system, 9.2μg/l (83.7 per cent reduction) in the SSF system and 11.0μg/l (80.6 per cent reduction) in the SF system, respectively. Results of ANOVA indicated that differences in concentration reduction of copper among the three wetlands were not statistically significant. The average concentration of chromium decreased from 1.31μg/l in influent to 0.4μg/l (69.5 per cent reduction) in all system designs. Copper concentrations were reduced consistently with increasing wetland retention time, with most of concentration reduction having occurred in the first wetland cell for all system designs.

This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors such as hydraulic retention time and hydraulic loading rate and its influence on the treatment dynamics. Because of intermittent feeding mode of VFCW systems and variation in its loading, its hydraulic behaviour is highly variable and need to be understood to optimize its treatment performance.

Tracer test were carried out using bromide ion with varying hydraulic loading rates (HLR) of 6.82 cm/d, 9.09 cm/d and 11.40 cm/d (i.e. equivalent to 75 L/d, 100L/d and 125 L/d). Tracer data is then analysed using the Residence Time Distribution (RTD) method.

RTD analysis showed that the increase in HLR increases the average hydraulic retention time (HRT). Subsequently, the increase in HLR results in a lower recovery of effluent, resulting in poor productivity in treatment. The study also showed that the removal of nitrogen and organic matter improved with increasing HRT. However, observations show no correlation between HRT and total solids removal.

A performance evaluation method (by tracer) is proposed to understand the hydraulics of flow in constructed wetlands, which has not been widely studied. Additionally, the dynamics of treatment in VFCWs treating septage may also be revealed by the tracer method. The study can be applied to any constructed wetlands designed for treatment of wastewater, septage or sludge.

The European Water Framework Directive is the basis of sustainable water resources management in the European Union. The required “good status” of waterbodies can be achieved only by encouraging the application of natural renewable‐energy‐driven ecological engineering. Ecotechnological methods in wastewater treatment (e.g. constructed wetlands) can remove more than 90 per cent of total N and P, and organic load. These methods also save up to 80 per cent of the cost and energy compared with central technical systems. Because ecomorphology in around 80 per cent of German streams and rivers is disturbed to a high degree, increased efforts for renaturalization are necessary. Successful control concerning first initiated measures shows that improvement of stream morphology has a remarkable positive influence on water ecology.

The University of Michigan (U-M) is planning its course toward carbon neutrality. A key component in U-M carbon accounting is the calculation of carbon sinks via estimation of carbon storage and biosequestration on U-M landholdings. Here, this paper aims to compare multiple remote sensing methods across U-M natural lands and urban campuses to determine the accurate and efficient protocol for land assessment and ecosystem service valuation that other institutions may scale as relevant.

This paper tested three remote sensing methods to determine land use and land cover (LULC), namely, unsupervised classification, supervised classification and supervised classification incorporating delineated wetlands. Using confusion matrices, this paper tested remote sensing approaches to ground-truthed data, the paper obtained via field-based vegetation surveys across a subset of U-M landholdings.

In natural areas, supervised classification incorporating delineated wetlands was the most accurate and efficient approach. In urban settings, maps incorporating institutional knowledge and campus tree surveys better estimated LULC. Using LULC and literature-based carbon data, this paper estimated that U-M lands store 1.37–3.68 million metric tons of carbon and sequester 45,000–86,000 Mt CO₂e/yr, valued at $2.2m–$4.3m annually ($50/metric ton, social cost of carbon).

This paper compared methods to identify an efficient and accurate remote sensing methodology to identify LULC and estimate carbon storage, biosequestration rates and economic values of ecosystem services provided.

The purpose of this paper is to describe the investigation of distribution of metals in water and sediment samples of Poydras‐Verret wetland, an area that has received approximately 40 years input of secondarily treated municipal effluent.

Water and sediment samples were analyzed for metals for a period of 18 months. These metals were also monitored for the secondarily treated effluent, and at a reference/control wetland that does not receive wastewater. Analysis of variance (ANOVA) and Student Newman‐Keuls post‐hoc ANOVA analysis were conducted to evaluate the pattern of metal distribution within the Poygras‐Verret wetland and compare results to the reference wetland. Heavy metal criteria established by United States Environmental Protection Agency (USEPA) and State of Louisiana were also used to assess the potential chronic and acute health impacts of heavy metals in the Poydras‐Verret wetland.

Concentrations of metals of the Poydras‐Verret wetland water are not different from those found in the reference wetland water, suggesting no observed accumulation of these metals within the receiving wetland water. All metals are below the acute criteria.

Historical data regarding metal accumulation in wetlands in the published literature is limited. This paper provides supporting evidence that using wetlands to assimilate wastewater could be a long‐term, practical solution with the side benefits including wetland restorations and protection from wave erosion and storm surge.

The purpose of this paper is to assess the water quality parameters resulting on: First, the flow direction in biofilters (ascending or descending), second, constructed wetland (CW) with local plant species and third, the combined system for the removal of organic matter and nutrients pollutants from water in arid regions.

An integrated system is presented and tested in situ with a vertical up-flow and down-flow biofilters. Two configurations schemes are followed by a three separated horizontal subsurface CWs: two planted with Phragmites australis, Typha latifolia and the third unplanted. The methodology is based on a statistical analysis of the collected data.

The present experiment demonstrated that the wetlands planted with P. australis and T. latifolia showed the highest removal. Moreover, T. latifolia performed better than P. australis for most of the parameters, notably in the first system, whereas the wetland efficiency indicated that P. australis contributed greatly to the removal of TP in the first system and NO₃-N in the second system. In general, for the highest removal efficiencies of the combined biofilters and wetlands system, the present study demonstrated that the first system performed better than the second for all the parameters.

The originality of the research is that it compares in situ two biofilter systems: vertical up-flow and down-flow biofilters. To avoid the effects of domestic wastewater that is discharged directly without treatment in the Oued Righ channel or in the lake, this integrated system can be one of the alternatives for wastewater treatment, as it reveals the need to protect aquatic ecosystems in arid regions, and can decrease the risks to human health and the environment.

The most common form of municipal waste disposal in the EU continues to be landfilling, from which leachate could seriously contaminate ground water aquifers that serve as drinking water sources. Constructed wetland is considered as a sustainable option as it facilitates water recycling in landfill sites using closed loop technology. In Slovenia constructed wetlands have been successfully developed and there are already 6 landfills that have been remediated using this technique. An innovative co‐natural approach that has been applied on the landfill site at Ormoz (1.5ha), allows a landfill site to become a bioreactor by permitting controlled infiltration. Leachate is purified using a constructed wetland covering 1,000m². The average hydraulic load is 12m³/d. Purified water will then be recycled through an underground irrigation system to fast growing trees. We assume that this solution will allow rapid stabilisation of the landfill site as the infiltrated water in the landfill site stimulates microbes to mineralise organic waste. There is no risk of leaks as the root systems of trees follow the non‐uniform settling of waste. Owing to the closed hydrological and pollution cycle, the impact on the environment and especially the risk of water contamination will be reduced.

The new campus of Tianjin University was designed, built and now operates following a green and sustainable concept. The campus’ eco-friendly water environment was formed by establishing a water recycling system. The campus is divided into three drainage sections based on the masterplan. Each drainage section adopts different methods of collecting, utilizing and discharging water according to specific conditions, aimed at achieving both high drainage capability and the efficient utilisation of rainwater. The campus was designed so runoff pollution is reduced through the utilisation of low-impact development methods, ensuring the quality of the recharge water. Through studying the fundamentals of treatment measures and models for simulating water quality, water circulation, constructed wetlands and pollution control of rain runoff, parameters for efficient water recycling could be mathematically forecast, ensuring that stakeholders can be continuously engaged in improving and preserving the water quality of landscaped water on campus. The overall system integrates a variety of measures being implemented into one cohesive entity, which contributes to establishing the sustainable and healthy water cycling system of the green campus.

The purpose of this paper is to describe the case of the Valorbio research project, in which students of different high-level programs were involved in the experimental work and in the dissemination of results in collaboration with the research team.

The inclusion in higher education curricula of content related to the sustainable development should be a preferred mechanism for the dissemination of good practices of sustainability. Another equally important way to achieve this is to involve students in research projects that seek solutions to the societal challenges related to sustainable growth. The Valorbio project aims to meet the needs for treating and reusing wastewater and solid waste. Its main goal was the development of modular systems for wastewater treatment based on constructed wetlands, exploring the possibility of the treatment systems being composed of solid waste and by-products from significant industrial sectors.

The students’ contribution to the research work was relevant and simultaneously allowed them to acquire skills on sustainable development. Additionally, the students contributed to the dissemination of the results. The Valorbio project can thus be considered a successful application of the concept of project-based learning (PBL), as a way to include sustainability issues content in the higher education curricula.

The applied experimental work had an original approach regarding the equipment design, the waste materials valuation, as well as the integration of waste treatment processes in the circular economy paradigm. This paper is the first reported PBL experience involving students of short-cycle technical–professional programs in partnership with first and second-level students and a research team.

Describes a study carried out to evaluate the accumulation of heavy metals by two different vascular aquatic plants in the artificial wetlands which were constructed for the treatment of municipal wastewater in Berlin, Germany. The studied plants were Pharagmites australis and Schoenoplectus lacustris. The investigated metals were: Zn, Cr, Cu, Fe, Cd, Ni and Pb. The translocation of such metals in the plant roots, stems and leaves was also determined. The level of metals in the influent and effluent of the wastewater, as well as the sludge, was investigated. The concentration factor of each metal by plants and sludge was further studied. Results revealed that P. australis has a higher tendency for the accumulation of metals than S. Lacustris. The level of metals was higher in roots, followed by leaves, then stems. Metals were more concentrated in the sludge than in the plants. Further study showed that the levels of metals in plants grown in the artificial wetlands were higher than in those grown in a “controlled” area. Concludes that vascular plants can act as scavengers of metals from the municipal wastewater while still maintaining a healthy status.