Search

Graphical abstract Highlights • Concentrations of heavy metals were significantly reduced in paper mill sludge by earthworm. • Heavy metals were accumulated by earthworm internal body. • High concentration of paper mill sludge showed the highest incidence of damaged tissues in earthworms. • Vermistabilization is a low-cost eco-friendly technology to combat land pollution. Abstract The present study demonstrates the vermistabilization of paper mill wastewater sludge (PMS) spiked with cow dung (CD) employing indigenous epigeic earthworm Perionyx excavatus Perrier. A total of six treatments were prepared along with a positive control (PC) and negative control (NC). Twenty earthworms were released into each treatment including PC and NC without earthworms. The different proportions viz., T1 (CD – 100%), T2 (PMS:CD – 1:3), T3 (PMS:CD – 1:2), T4 (PMS:CD – 1:1), T5 (PMS:CD – 3:1), T6 (PMS:CD – 2:1), PC (PMS – 100%) and NC (PMS – 100%) and changes in chemical parameters and microbial properties were recorded during the course of 60 days. Vermistabilization caused a significant decrease in the level of heavy metals: Cd (2.9–27.8%), Cu (0.22–42.3%), Pb (1.3–56.3%) and Cr (0.8–46.2%). The bioconcentration factor (BCFs) was also calculated and great amount of heavy metals accumulated in their body (mg kg−1) that ranged from 0.31 ± 0.003–0.45 ± 0.007 for Cd, 0.12 ± 0.005–0.24 ± 0.003 for Cu, 0.15 ± 0.005–0.31 ± 0.006 for Pb and 0.29 ± 0.007–0.56 ± 0.001 mg kg−1 for Cr, accumulation of heavy metals are in the order: Cr > Cd > Pb > Cu. The physicochemical parameters of earthworm treated substrate such as electrical conductivity, total nitrogen, total phosphorus and total potassium were significantly increased; whereas, pH, total organic carbon, C:N ratio (carbon: nitrogen) and C:P ratio (carbon: phosphorus) were reduced after 60 days of vermistabilization. The vermistabilized materials also had a higher population of bacteria (98.90 ± 0.30 CFU × 106 g−1), fungi (43.75 ± 0.55 CFU × 103 g−1) and actinomycetes (67.65 ± 0.45 CFU × 105 g−1) than initial mixtures. Moreover, several histopathological changes were observed in earthworm tissues viz., disintegration of cells, irregular surface of epidermis, cellular debris, irregular cellular compartmentation, and oval-shaped nucleus. Higher level of histopathological abnormalities was recorded in PC (PMS-100%) while none were detected in lower concentrations of PMS. Furthermore, the study concludes that the paper mill sludge in a mixture of cow dung (1:1 ratio) can be a useful proposition for utilizing this hazardous waste through the adoption of vermitechnology. [ABSTRACT FROM AUTHOR]

The largest Phragmites reed field in the world, with a historical area of approximately 1000 km 2 , is located in the Liaohe Delta in northeastern China. The Phragmites wetlands are extensively managed to maximize the production of reed biomass for the paper industry. Based on satellite remote sensing we estimated that the total area of the Phragmites wetlands has decreased from 857 km 2 in 2003 to 786 km 2 in 2009 to accommodate oil field infrastructure and societal developments. However, at the same time the production of Phragmites biomass used for the production of reed pulp has increased to 400,000 metric tons per year. This paper describes the great efforts that have been made to increase the Phragmites yields for the paper industry, including (1) diversion of freshwater from rivers to the Phragmites fields, (2) management of the water table, (3) harvesting and burning for pest control, and (4) seawater irrigation to rehabilitate Phragmites fields infested with weeds. The paper industry has facilitated the conservation of the Phragmites wetlands and their associated ecosystem services. Besides being a source for fiber, the wetlands provide important habitat for wildlife, sequester carbon, and create job opportunities and economic income for the local people. [ABSTRACT FROM AUTHOR]

The present study deals with the bioremediation of potentially hazardous pulp and paper mill effluent by a laccase producing Paenibacillus sp. strain LD-1 (JX499920) isolated from contaminated soil sample by lignin enrichment method. The bacterium effectively reduced pollution parameters (colour 68%, lignin 54%, phenol 86%, BOD 83% and COD 78%) after 144 h of treatment at 34 ± 1 °C and 120 rpm. GC–MS analysis of control and treated samples showed that concentration of most of the low molecular weight phenolic compounds like 2-methoxyphenol, 2,6-dimethoxy phenol, 2-methoxy-4-ethyl-phenol, 3-allyl-6-methoxyphenol, ethanone 1-(-4-hydroxy-3,5-dimethoxyphenyl), benzoic acid, 2-methoxy-4-(1-propenyl) phenol and 4-methoxycinnamic acid present in control untreated effluent were reduced after bacterial treatment. The toxicity assessments were carried out with treated and untreated effluent by studying the growth and germination of seeds of mung bean ( Vigna radiata L.). The mung bean bioassay confirmed the detoxification of effluent after bacterial treatment. [ABSTRACT FROM AUTHOR]

Heavy metal content has become a serious issue with increase in compost application in agricultural land. The bioavailable fraction (water soluble and diethylene triamine pentaacetic acid (DTPA) extractable) is the major concern comparing to the total concentration as it can be taken up by plants which in turn affects the human health. Thus, this study was carried out to determine the variation in bioavailable and leachable fraction of heavy metals (Cd, Cu, Fe, Ni, Pb, Cr, Zn, Hg and Mn) and to assess the influence of temperature, pH, organic matter degradation and humification during rotary drum composting of paper mill sludge (PMS) for 20 days. A total concentration of all the metals as well as nutrients increased during composting. The Hg was not detected in water soluble and DTPA extractable fraction, whereas Pb and Cr were also not detected in water soluble fraction in all the trials. A decreasing trend was observed in leachable quantity for all the metals during composting. Water extractable quantity increased for Fe and Cu during composting. Organic matter degradation and humification during composting influences the variation in bioavailability and leachability of heavy metals, which can be optimized by applying appropriate proportion of cow dung during rotary drum composting of PMS. [ABSTRACT FROM AUTHOR]

The results of physico-chemical analysis of pulp and paper mill effluent sedimented sludge revealed the presence of heavy metals (mg l −1 ) Fe (67.53), Zn (13.90), Cu (2.15), Cr (2.30), Cd (0.255), Mn (11.0), Ni (3.30), and Pb (1.05) along with persistent chlorolignin. The major persistent organic pollutants detected by GC–MS were ethane, 1,1-diethoxy; tetradecanoic acid; furane 2,5-dimethyl; n -hexadecanoic acid; nonacosane, trimethylenebis-1,3-dioxolane; 1,3-dioxolane, 2-(phynylmethyl). Twelve representative native plants were noted based on their population number growing on pulp and paper sludge and evaluated for their phytoextraction potential of heavy metals. The result revealed that Triticum aestivum was found as root accumulator for all metals except Cu. Similarly, the Brassica campestris accumulated all metals maximum in root except Ni, Fe and Pb. While, Eclipta alba accumulated majority of metals in their shoot and leaves, But Solanum nigrum, Rumex dentatus accumulated metals in root and shoot both. Rananculus scleratus accumulated all the tested metals in their aerial parts except Cd and Pb. Cammelina benghalensis accumulated metals in root except Cd, Pd. Similarly the Phragmites cummunis and Ricinus cummunis accumulated majority of metals in their shoot and leaves. It was also noted that several evaluated plant showed bioconcentration factor (BCF) greater than one for accumulated metals i.e. Pb in T . aestivum (1.285), C . benghalensis (5.142), Cannabis sativa (3.466), P . cummunis (7.180), R . cummunis (66.80) was also noted. Furthermore, greater than one translocation factor (TF) for all these plants showed strong evidence for phytoextraction and in situ remediation potential of these plants. The overall order of phytoextraction potential of native wetland plants were C . sativa > P . cummunis > C . benghalensis > T . aestivum > B . campestris > E . alba . [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the predictive ability of gene-expression programming (GEP) in the estimation of methane yield (Y m ) and effluent substrate (S e ) produced by two anaerobic filters. The modeling study was carried out using the data obtained from two upflow anaerobic filters – one mesophilic (35°C) and one thermophilic (55°C) – operated for the treatment of paper-mill wastewater under varying organic loadings. The GEP model was composed of three inputs, hydraulic retention time (T hr ), organic loading rate (R ol ), and influent substrate (S i ), and one output, either S e or Y m . The Stover–Kincannon model was also used for data analysis and to evaluate the prediction ability. Three statistical criteria, root mean square error (RMSE), determination coefficient (R 2), and Akaike''s information criteria (AIC), were the means used for comparison. The results showed that the GEP approach predicted the performance of both anaerobic filters much better than the Stover–Kincannon model. [Copyright &y& Elsevier]

Green roofs provide ecological benefits to urban areas and the use of biodiverse communities enables the vegetation to recover from stress caused by dry conditions. Recycled waste materials are often used as substrates and extensive research on their physical and chemical properties has been carried out. In this study, we evaluated different amounts of deinking sludge pellets as an alternative substrate component in establishing drought-tolerant herbaceous communities on green roofs. Three substrates were prepared aimed at providing decreasing fertility: a commercial substrate composed of tephra and compost (control); an experimental substrate composed of tephra, pellets, and compost, and another one consisting of tephra and pellets. A mixture of 30 species, including native herbaceous species and sedum, of Mediterranean phytocenosis, was transplanted on all the substrates. A physical and chemical characterization of the substrates was carried out. The plant ecological functionality, life forms and richness, and the abundance of flower-visiting insects were studied. The substrate composition affected the plant community cover and richness. The amount of pellets in the two experimental substrates reduced the availability of resources (nitrogen and moisture content) promoting diversity, in terms of the number of species, as well as the hardiness of the vegetation. Our results are of great interest for obtaining a biodiverse mosaic habitat in green infrastructures, by measuring out the quantity of infertile materials in the substrates. [ABSTRACT FROM AUTHOR]

Management of industrial sludge is a big challenge for developing countries. Composting is an economical and viable option to manage and treat an industrial sludge. However, efficient compost production requires nature of materials involved, process understanding and physics behind the process. We investigated the physical parameters during composting of solid pulp and paper mill sludge in 550 L rotary drum composter. Variation in physical parameters such as bulk density, volatile solids, moisture content, free air space, void ratio, ash content and particle density were analyzed over the period of composting. Bulk density was observed increasing, whereas free air space was showed declining trend and observed 52% in end compost. The particle density was observed to be increasing from 610 to 680 kg m −3 . End compost was analyzed for nutritional parameters and seen to be increasing over the period of composting. A strong relationship was found between various physical parameters. Pearson’s correlation coefficient matrix was formed between free air space, bulk density, moisture content and particle density. [ABSTRACT FROM AUTHOR]

River water irrigation is used to reduce soil salinity in the reed fields of the Shuangtai Estuary Wetland in Northeast China to improve the reed quality for paper industry; however, quantitative effects of this approach have not yet been investigated. In this study, the effect of irrigation was investigated by conducting comprehensive field observations and numerical simulations, and the necessary irrigation water volume was determined. The field observations included determination of (1) the relation between surface soil salinity and reed yield; (2) vertical profile of soil salinity before and after the irrigation period; and (3) variation of depth and salinity of the standing water during irrigation and the rate of rainwater interception by reed leaves. Our findings suggested that (1) the reed yield decreased remarkably when the surface soil salinity exceeded 5‰ and (2) irrigation could reduce salinity to below this level. From our observations, water budget in the irrigated reed fields was evaluated. A numerical model was constructed to simulate the salinity reduction process by assuming that the salinity flux across the ground surface was proportional to the salinity difference between the standing water and the surface soil. The model parameters were calibrated using the results of observation (3) such that the model successfully reproduced the observed time series of standing water salinity. A series of numerical experiments were performed using the model to determine the irrigation water volume necessary for sufficient soil salinity reduction. The results suggested that soil salinity reduction depended greatly on rainfall during the reed growth period. Further, an initial irrigation depth of about 20 cm was sufficient for lowering the salinity to 5‰ even during rainfall shortage that occurred every 10 years on an average. Replacing the saline standing water before intensive rainfall events with rainwater was found to be an effective approach to lower the surface soil salinity. [ABSTRACT FROM AUTHOR]

Abstract: The ability of Kraft lignin, a waste product of paper production, for removing copper, zinc, cadmium and chromium ions from water was investigated. The studies were conducted by a batch method to determine equilibrium parameters. The adsorbed heavy metal ions followed the order: Cr(VI)≫Cd(II)>Cu(II)>Zn(II). The influence of other ions such as Ni(II), Cd(II) and Pb(II), on Cu(II) adsorption by Kraft lignin was evaluated. Obtained results support the idea that adsorption behaviour of heavy metal ions have to be perceived from the aspect of possible influence of interfering ion species. [Copyright &y& Elsevier]

Despite growing health concerns and increasing water scarcity, adequate wastewater treatment and reuse remains limited in India. Low-cost, decentralised, and nature-based on-site sanitation systems could play a key role in a circular water approach. This paper evaluates the performance of a Wastewater Fertigated Short Rotation Coppice (wfSRC) system based on willow, poplar, and bamboo species as a potential solution, offering low-cost, efficient water treatment, and high biomass production. Through a full-scale wfSRC pilot plant (250 m3·day−1 municipal wastewater on 6864 m2) established at Aligarh Muslim University, Uttar Pradesh, India, treatment capacities, biomass production rates, and contamination tolerance of different willow, poplar, and bamboo species were investigated. The chemical compositions of incoming wastewater, percolation water, soil, and biomass were monitored regularly. Despite the high load, all plant sections of the wfSRC system showed efficient removal of wastewater-originated pollutants. BOD5 and COD removal efficiencies were up to 99% and 95% respectively. Removal efficiencies for PO4-P reached 93% and for TN 91%. In general, total nitrogen and phosphate loads appear to be the limiting design parameters under the conditions at Aligarh to meet all discharge limits in India. Biomass production was projected to be >225 tDM·ha−1·yr−1 for bamboo, 65 tDM·ha−1·yr−1 for willow, and 206 tDM·ha−1·yr−1 for poplar. The pilot, conducted from March 2022 to June 2023, showcased how these densely planted agroforestry systems can effectively treat wastewater through natural processes such as oxidation, microbial degradation, and plant uptake. The findings demonstrate wfSRC's potential to serve as a nature-based, sustainable approach to wastewater treatment, particularly beneficial for suburban and rural areas in India and similar regions worldwide. This paper also provides recommendations for future implementation of wfSRC systems, emphasizing the need for careful planning regarding plant selection, system design, and operational strategies to maximize treatment efficiency and biomass production. [ABSTRACT FROM AUTHOR]

Abstract: Constructed Technosols deliberately combine technogenic materials to obtain specific services (e.g. plant biomass production) in particular contexts (e.g. industrial wasteland reclamation). Their ecological reclamation by key members of the soil fauna, such as earthworms, is a promising way to ensure such services. However, literature which treats these animals as a biological agent of constructed Technosol functioning is very scarce. This work assesses the effects of the composition of a constructed Technosol (i.e. the proportions of the constituent materials) on earthworm (Lumbricus terrestris) surface cast production and composition, and to a lesser extent on earthworm survival and biomass. Earthworms were placed in laboratory microcosms made of different proportions of materials: green-waste compost (GWC) and thermally treated industrial soil mixed with paper mill sludge (TIS/PS), for 30 days. We found that 25% of GWC on the surface and 75% of TIS/PS below was the most beneficial composition in that it gave the highest body mass gain. Furthermore, this composition generated a moderate surface cast production compared to other compositions and an increase in microorganism activity and number compared to non-ingested by earthworm soil. This composition also led to casts with bacteria of diverse morphologies and largest microaggregates compared to compositions without GWC, resulting from the ingestion and mixing of the two materials in the earthworm gut. However, earthworms did not modify the carbon contents of surface casts. This laboratory approach was a necessary step before field assessment of ecological reclamation by earthworms. From a soil engineering point of view, this contributes to better-managed soil construction for ecological reclamation. [Copyright &y& Elsevier]

• Control latrine played a typical geochemical behavior of a contaminant source. • Alternative latrine oxidized almost completely ammonium to nitrate. • Nitrate removal efficiency promoted by sawdust layer was of 42% on average. • Isotopes analyses corroborated N-species hydrogeochemistry trends across latrines. • Relative placement of sawdust and BOF slag layers impacted denitrifiers performance. Nutrients, like nitrate and phosphate, and pathogens are the primary contaminants released into groundwater by on-site sanitation systems, which are an effluent disposal outcome for regions not covered by sanitation infrastructure, as periurban communities in developing countries. As appropriate setback distances between pit latrines and supply wells often cannot be met to avoid groundwater contamination, especially in a densely-populated situation, efficient, low-cost and accessible technologies are extremely necessary to protect water resources and surpass critical and persistent public health problems. This paper presents 1-year field-testing of an alternative latrine (AL) that incorporates two waste materials as permeable reactive barriers (PRB) in an irregular settlement at the municipality of São Paulo (Brazil). Basic oxygen furnace (BOF) slag in contact with wastewater effluent increases its pH level, which causes pathogens inactivation and phosphate adsorption. Sawdust under water saturation creates reducing conditions that encourage the growth of denitrifying bacteria that remove nitrate. A control latrine (CL) was constructed 90 m apart from AL with similar hydraulic characteristics and nonreactive materials for hydrochemical comparison. It was evident for AL the formation of well-defined nitrification and denitrification reaction zones, whereas CL overall presented nitrogen in its ammoniacal form, with incipient nitrate production at CL bottom, indicating that nitrification is probably boosted below that. BOF slag had attenuated microorganisms and phosphate almost completely, but nitrate removal average efficiency was 42%. The high pH effluent generated in BOF media may have also affected in the short-term the denitrifying bacteria in sawdust barrier 1 m below. The inverted position of the reactive barriers, i.e., sawdust PRB overlying BOF slag PRB, should be a more suitable design to achieve nitrate and pathogens removal. This kind of sanitation solution employing cheap and accessible waste materials have never been applied in the design proposed in this paper and also was a novelty for Brazilian context, proving to be a suitable technology to meet local needs. [ABSTRACT FROM AUTHOR]

Willow is considered an ideal plant species for environmental applications, including phytoremediation. Improving planting efficiency and reducing the costs of phytoremediation have become key steps for increasing its application. This paper reports the most update-to-date information on frequently used techniques for establishing willow, including plant material, planting methods, and the factors influencing the early establishment of trees in the field. The five main types of planting materials (rods, cuttings, billets, micro-cuttings and single-bud short branches), and the seven main planting techniques, especially different vertical and horizontal planting directions, were assessed. Factors affecting willow establishment were also reviewed, including the characteristics of planting materials (i.e., clones, cutting phenology, propagules size, pre-treatments), operation during planting (i.e., timing, orientation and planting depth) and post-planting management (i.e., soil conditions and weed management). New planting approaches with small-sized cuttings (of about 5 cm in length) have been recently proposed showing promising economical and effectiveness characteristics, especially for the establishment of willows in harsh soil and challenging conditions. [ABSTRACT FROM AUTHOR]

Upgrading treated wastewater systems can provide reclaimed water for different uses. In this paper, the potential for wetland creation and maintenance is evaluated. The upgrading treatment consists of intensified vertical flow constructed wetlands (VFCWs), where the physicochemical and microbiological water quality is improved, followed by free-water surface constructed wetlands (FWSCWs), where biodiversity is enhanced. This renaturalization system has been implemented in two wastewater treatment plants (WWTPs): Monasterios, where one VFCW 60 m2 and two FWSCWs (50 m2 each) have been built, and Carricola, where two VFCWs in series (20 m2 each) have been constructed. The VFCWs were filled with drinking water treatment sludge (DWTS), a waste produced in drinking water treatment plants, hence the circularity of the project. Data obtained during the first year of operation is presented. The mean hydraulic loading rates in the VFCWs were 0.79 and 0.62 m/d in Monasterios and Carricola, respectively. In FWSCWs, the HLRs were 0.35 and 0.32 m/d in FWSCW1, which receives the effluent of the VFCW, and FWSCW2, which receives the secondary treatment effluent, respectively. In the VFCWs, an important reduction of total phosphorus was achieved, 77% in Monasterios and 70% in Carricola, and other pollutants were fairly reduced as well. In FWSCWs, some pollutants, such as total nitrogen or phosphorus, were reduced, but other, such as total suspended solids or organic matter, increased due to algae growth and external inputs. The critical point is that biodiversity is increased thanks to these systems, aquatic invertebrate presented better diversity indexes in the FWSCW receiving the upgraded water from the intensified VFCW. Birds, amphibians, and reptiles have also colonised the created habitats. • Treated wastewater can be upgraded by intensified vertical flow constructed wetlands. • Drinking water treatment sludge is an appropriate adsorbent material. • Valorisation of drinking water treatment sludge integrates circularity in urban water cycle. • Upgraded water benefits the receiving water bodies, enhancing biodiversity. • Birds use the created wetlands to feed, rest and nest. [ABSTRACT FROM AUTHOR]

This special issue of Ecological Engineering provides an overview of research within the Everglades Stormwater Treatment Areas (STAs) over the past decade to understand the ecology and the biogeochemical processes that affect phosphorus (P) retention in these constructed wetlands. This research was established within the South Florida Water Management District's Restoration Strategies Science Plan (RSSP). The RSSP was developed in 2012, updated in 2018, and produced a total of 21 studies. The goal of RSSP research is improve understanding of the factors contributing to P retention, to support management of the STAs to attain and sustain a stringent outflow total P concentration goal (i.e., the Water Quality Based Effluent Limit or WQBEL) and to maintain the wetland plant communities used to achieve this goal. Compliance with the WQBEL will reduce P loads to the Everglades to support restore and maintain this special ecosystem. This synthesis paper presents an overview of the STAs and their purpose and then summarizes the findings from the publications included in this special issue as well as previous STA related research. From this synthesis, a list of potential management options to enhance P retention in the STAs is presented. • Stormwater Treatment Areas (STAs) built to reduce P in runoff entering the Everglades. • STA discharge must meet strict low P concentration limits. • P biogeochemistry research conducted to support management of the STAs. • P removed by particle settling, biogeochemical processes and plant uptake. • Fauna excretion, bioturbation, and internal loads substantially affect P retention. [ABSTRACT FROM AUTHOR]

Based on the complex population structure of fish species in Songhua River, this paper broke through the present method modeling by the single target species and introduced a developed approach classified by different spawning habits to evaluate ecological flow. Three main spawning periods and two spawning types were respectively analyzed combining with biographical information. For the characteristic of abundant branching channel and wide floodplain in study area, MIKE21 hydrodynamic model was applied to simulate hydrological condition. Combing the habitat preference curves and hydrodynamic results, the composite suitability index for the study reach was attained. At the same time, the lasting time of fish incubation was used to suggest the flow duration. At last, this paper put forward the optimal discharge, flow duration, occurrence time and frequency in April, May and June-July respectively. Using this result, the ecological flow process can effectively support to the management strategies for rational allocation of water resources. [ABSTRACT FROM AUTHOR]

This paper describes the ecology and management of two flow-through created wetlands that, in turn, defined 30 years of research by Bill Mitsch, 20 years in Columbus, Ohio (1992–2012) and 10 years in Naples, Florida (2012−2022). The Olentangy River Wetland Research Park was built in several stages from 1993 through 2010. The first stage was the creation of dual 1-ha kidney-shaped wetlands primarily fed by pumped Olentangy River water. A pattern of inflow that depended on river stage was maintained for 17 years. The two experimental wetlands were established by planting one of the wetlands with a variety of wetland macrophytes and leaving the second wetland unplanted to ultimately determine whether human introduction of wetland plants matter in the long run. In addition to maintaining data collection for hydrology, water quality, and other functions, these wetlands and several others constructed on the 20-ha floodplain site were heavily used as was the mesocosm compound, mostly for short-term (2 to 3 year) experiments by graduate students. Another 20-ha created wetland complex, called Freedom Park Wetlands, was constructed in 2007–2008 in Naples, Florida, at an abandoned citrus grove, to seasonally treat urban stormwater runoff. During that wet season, the design calls for an average water detention time of 18 days. The wetland system included a 1.9-ha deepwater pond for temporary storage of the urban stormwater pulses from what is mostly an urban watershed, followed by 2.7 ha of shallower vegetated wetland ponds designed to sequentially improve water quality. Within each wetland, there are three deep-water cells and two shallow-water cells. The water eventually exits the treatment wetlands via a rectangular and travels diffusely through a restored bottomland forest to the Gordon River and ultimately toward Naples Bay and the Gulf of Mexico. During our tenure at Florida Gulf Coast University's (FGCU) Everglades Wetland Research Park, Freedom Park was a venue with active mesocosm experiments in a constructed mesocosm compound. Several of these mesocosm experiments were the subjects of master's theses from FGCU and doctoral dissertations from our partner, University of South Florida. Our students also contributed to the local environmental communities by giving tours of the Freedom Park wetlands and our mesocosm research. • This paper describes the ecology and management of two created wetlands. • The Olentangy River Wetland Research Park in Ohio, USA has provided data since 1994. • The Freedom Park wetlands in Florida, USA were constructed in 2007–2008. • Both wetlands offer ecosystem services (i.e. nutrient reduction and flood protection). • These wetlands provide the framework for thirty years of wetlands research. [ABSTRACT FROM AUTHOR]

Highlights: [•] We tested the effects of mixed organic amendments on manufactured soil. [•] properties and tree growth. [•] We tested the effects of different soil emplacement methods on the establishment of seedlings of English Oak (Q. Robur) and alder (A. glutinosa). [•] Paper mill crumb decomposed more rapidly than green waste compost, producing greater concentrations of methane and releasing more plant available nutrients. [•] Alnus glutinosa established well under poor soil conditions, but later growth was affected. [Copyright &y& Elsevier]

Abstract Restoring riparian shade to formerly forested streams in cleared land is an important step in the restoration of stream ecological health. In a companion paper, we validated a numerical model for diffuse non-interceptance (difn) against measurements made in precisely-constructed physical models for two simplified geometries ‘canyon’ and ‘cylinder’ with trees lacking canopy ‘shape’. In this paper, we extend the model to include canopy ‘shape’ by representing trees as ellipses or kites, and quantifying shading from canopy overhang of the channel. The ratio of tree height (h) to stream width (w) strongly influences stream shade and is a key parameter when scoping riparian revegetation. Canopy width, overhang and viewpoint affect stream shade and could profitably be included in water temperature and aquatic plant growth models. Tree shape has a second-order effect on shade, most noticeably near the stream banks. The model predicts shade assuming a sky of uniform radiance (viz., it predicts shade to diffuse radiation) on the premise that difn is a useful index of long-term averaged light exposure. The model successfully reproduced the trajectory of shade reductions following riparian restoration predicted using a published physically-based model, confirming its suitability for scoping riparian shade restoration. While it would be feasible to include direct radiation in the model, this would require additional input data and computational effort. [ABSTRACT FROM AUTHOR]

Graphical abstract This paper examines the scientific evidence underpinning four hypotheses about the role of plants in bioretention systems: (i) Planted systems are more effective than unplanted systems, (ii) Plant species differ in their effectiveness, (iii) Native species are more effective than exotic ones, (iv) Diverse systems are more efficient than monocultures. Highlights • Manuals are often based on hypotheses on plant role in bioretention, not evidences. • Plants have a positive effect on permeability and nitrogen removal. • Right plant species is crucial for nitrogen not TSS, phosphorus, metals removal. • Native plants may help biodiversity, but not hydrologic or treatment performances. • Diverse plantings can be more resilient, but will not necessarily perform better. Abstract Plants are essential components of bioretention systems, with bioretention design-guides around the world providing extensive advice on the role of selection of plants to maximize system performance and sustainability. Four principal hypotheses regarding the role of plants have been identified in bioretention design manuals: (i) Planted systems are more effective than unplanted systems, (ii) Plant species differ in their effectiveness, (iii) Native species are more effective than exotic ones, (iv) Diverse systems are more efficient than monocultures. This paper examines the extent to which these hypotheses are supported by the scientific literature. Comparison of planted and unplanted systems show that increased permeability and hydraulic conductivity, as well as removal of nitrogen, are the main benefits of the presence of plants in bioretention. Knowledge on their positive effect on hydrocarbons remains fragmented, although there is evidence from phytoremediation studies in other plant-based technologies. Choosing the right species makes a difference in hydraulic performance and nitrogen removal, with root traits being identified as important predictors of performance. No scientific results can support the hypothesis that native plants or diversely-planted systems offer better performance than systems planted with fewer species or with exotic species. Questions remain regarding the plant-microbe interaction in the bioretention context, the role of biomacropores in pollutant migration or the differential impact of plant choice on performance. [ABSTRACT FROM AUTHOR]

Highlights • This paper presents the current experience of Polish Sludge Treatment Reed Beds. • 6 Polish reed systems were analyzed. • Sludge Treatment Reed Beds could be economical and useful solution in small and medium-sized wastewater treatment plants. • Sewage sludge utilized in Sludge Treatment Reed Beds can be potentially a good fertilizer. • Proper work of Sludge Treatment Red Beds requires right design and maintenance. Abstract Sludge Treatment Reed Beds (STRBs) is the technology of sludge treatment, which is based on natural processes occurring in the environment, in specially designed and operated facilities to achieve benefits for the environment. Integrated dewatering and stabilization occur in reed systems. For economic and environmental reasons it is an attractive solution, especially in rural areas where there are no appropriate facilities. In the recent years many European countries like Denmark, France or Germany have applied this technology for sewage sludge management. Poland has also some experience in dewatering and stabilization of sewage sludge in STRB systems. The objective of the paper is to present the current experience and lessons learned from the operation and to assess the quality of sewage sludge from STRBs in Poland. The analyzed sewage sludge was treated in STRBs located in five wastewater treatment plants: Darżlubie, Swarzewo, Zambrów, Nadole and Gniewino, Poland. Two from the analyzed systems (Darżlubie and Swarzewo) worked only in a pilot scale and three of them (Darżlubie, Swarzewo and Nadole) did not work any longer. In the collected samples of sludge the evaluation of dewatering and stabilization processes, fertilizer properties, as well as heavy metals concentrations were determined. The average dry matter content in sludge treated in Polish STRBs was from 11.2 to even 53.7%. The degree of mineralization in analyzed systems was from 31.4 to 68.6%. The average nutrient contents was for nitrogen from 1.0 to 10% DM and for phosphorus from 0.2 to 1.0% DM. The conducted research confirms that sludge treated in STRBs is dewatered and stabilized, thus it could be used as a fertilizer in agriculture. [ABSTRACT FROM AUTHOR]

This paper summarizes 19 papers published in a special issue of Ecological Engineering under the general banner of wetlands and carbon. Many of the papers were presented at a special session at EcoSummit 2016 in Montpellier, France in August-September 2016. The papers are in four general categories: estimating greenhouse gas fluxes with eddy covariance; methane and other greenhouse gas emissions from wetlands; carbon sequestration by wetlands; and organic carbon decomposition in wetlands. Overall, we found that further development and wider use of eddy covariance measuring stations could help clarify long-term annual budgets of CO 2 and CH 4 in wetlands and, while CH 4 fluxes in some coastal wetlands such as mangroves can be negligible, some inland wetlands can be significant sources of CH 4 where hydroperiods are the major determinants of the emission rates. The papers here demonstrated a variety of parameters determining dynamics of methane fluxes and carbon sequestration in different wetlands and lead us to suggest that more attention should be paid to detailed analysis of the impact of environmental and management factors on carbon budgets in wetlands. Carbon sequestration is almost always estimated by soil dating methods such as with 137 Cs and 210Pb isotopes and results continue to show order of magnitude differences among systems but sometimes among laboratories. This is due to the inexact nature of estimating soil dates over relatively short (∼50 year) time horizons. The idea of capping landfills, which are enormous methane sources, with wetlands which could then turn them into carbon sinks is worth investigating further but the design of these systems is still in its infancy. Organic carbon decomposition in wetlands has been investigated extensively for decades and more recently on the biogeochemical processes. ‘Enzymic latches” such as phenol oxidase, which can break down phenolics and therefore speed up decomposition, may be key controllers of organic matter decomposition in waterlogged and submerged soils in wetlands. The best approach for balancing greenhouse gases and carbon sequestration remains an enigma, but the papers in this special issue take us one step closer to providing clarity. [ABSTRACT FROM AUTHOR]

In recent years, large parts of arid and semi-arid areas in the world are dealing with water restrictions. In these areas, wetlands provide habitats for migratory birds and have a critical role in socio-ecological systems. Generally, in these areas, changing water-use patterns because of land-use change and water limitation because of climate change have led to the loss of wide areas of wetlands. Wetland restoration is suggested to restore the functions and values of wetlands that have been destroyed or affected by stresses. In this paper, a new application of wetland restoration prioritizing is introduced; restoration prioritizing to reduce the negative effects of drought. In this method, areas with the highest priority for restoration will be determined in a wetland destroyed because of water limitations. Multicriteria-spatial decision support system (MC-SDSS) was used to plan a scheme for Hamun wetlands restoration prioritizing in order to reduce the negative effects of drought and to restore the wetlands. This prioritization-determined areas that are valuable for Long-term water conservation, reduce the negative effects of dust storms and conserve water bird’s habitats. This method was used in a wetland that is the only water resource in the middle of a wide arid plain. Because of water limitation, it is not possible to restore the hole wetland; therefore, different parts of this wetland were prioritized for restoration. Based on the results, it is possible to produce a model to determine which priority can be restored in each amount of water volume. In this way, it becomes clear for decision-makers to select areas for restoration in different volumes of water. The result of this study shows that since MC-SDSS decreases conflicts between alternatives in a decision-making process and uses their spatial situation, it is a preferred method to balance among conflicting goals. Furthermore, because spatial data are the most important parts of MC-SDSS, this paper shows the ability of remote sensing to be used in MC-SDSS method. It seems that in the future; remote sensing will have the most important role in MC-SDSS. [ABSTRACT FROM AUTHOR]

Managed treatment wetlands technology is now used around the world to treat wastewater and stormwater by removing nutrients and other contaminants to obtain a desired water quality. In this paper we present a brief review of a large-scale application of the nature-based technology known as stormwater treatment areas (STAs). These STAs were constructed to treat agricultural and urban runoff to reduce outflow total phosphorus (TP) concentrations to <20 μg P L−1, which is required to protect downstream water quality and preserve the remaining Everglades ecosystem. Five STAs with a total area of approximately 25,000 ha were built at strategic locations to reduce TP loads to the Everglades Protection Area. For the past three decades, these Everglades STAs have done remarkable job by 70 to 85% TP load reduction, with an average outflow TP concentrations of 15-40 μg P L−1. In this Everglades STAs special issue, we present research findings on the influence of both external and internal drivers influencing STA performance and potential adaptive management strategies to enhance treatment efficiency to further reduce outflow TP concentrations. • Introduction of the Everglades STAs – largest constructed treatment wetland network in the world. • Everglades STAs serve as 'kidneys' of the Everglades ecosystem by reducing phosphorus loads to downstream waterbodies. • Phosphorus loading is one of the key drivers regulating treatment efficiency STAs. [ABSTRACT FROM AUTHOR]

Vegetation in front of levees, dikes and seawalls can decrease wave energy and therefore contribute to the safety against flooding. However, wave damping predictions by vegetation are still inaccurate due to measurement and modelling uncertainties. Many studies focused on finding reliable predictive tools using scaled flume tests with vegetation mimics. Scaling down vegetation can however lead to discrepancies with realistic scales, known as scale errors. In this work scaled tests were conducted on 3D-printed elastic replicas of willow trees and compared with real-scale experiments. We identified differences in measured wave dissipation between the scaled hydraulic model (1:10) and its real-scale prototype with 5 m high live willow trees under storm conditions (1:1). The maximum measured wave damping (30%) was roughly 1.5 times higher than the real-scale experiments (20%). Following the same trend of the real-scale experiments, this amount of wave height damping declined for larger water levels. Largest effects are argued to be due to increased viscous damping (smaller branch Reynolds numbers) and non-exact flexibility scaling. These significant deviations illustrate that full-scale experiments, although expensive, are still needed to validate the results of scaled experiments for woody vegetation. Alternatively, accounting for these discrepancies can make scaled experiments more reliable and expensive real-scale experiments less needed for wave damping studies on woody vegetation. • A forest with Froude and Cauchy scaled mimics of real pollard willow trees with detailed multi-scale branch structure was 3D printed. • Wave damping for the specific tested scaled pollard willow forest increased by a factor 1.5 compared to a real-scale 40-m long forest: 30% instead of 20% wave height reduction. • The major scale and model effects are inferred to be viscous effects, and imperfect elasticity scaling, respectively, both having the same order of magnitude. • Branch deflection was observed for the real-scale and scaled tests with the scaled forest appearing too stiff. • For realistic multi-scale trees, turbulence processes are different for the different elements, and dimensionless numbers have a range of values for different parts. In this paper the main dimensionless numbers, Reynolds and Cauchy, were calculated for different parts of the trees. [ABSTRACT FROM AUTHOR]

This editorial describes a 10-paper special issue that arises from the 4th International Conference on Soil Bio- and Eco-Engineering (SBEE2016) ‘The Use of Vegetation to Improve Slope Stability’ held at the University of Sydney, Australia, in July 2016. The conference focused on current topics and progress in slope stability research and the successful application of soil bio-engineering and eco-engineering techniques to stabilizing slopes in a variety of climatic and geomorphic settings. The papers are divided into the following categories: vegetation and slope stability (1 paper); root-soil interactions (5 papers); slope stability modelling (2 papers); eco-engineering and land restoration (2 papers). Most of the papers present case studies documenting bio- and eco-engineering techniques, site-specific investigations or innovative slope stability modelling approaches and two papers are aimed at standardizing data collection and sustainability assessment practices within the discipline. Case studies are presented by scientific researchers, practitioners, geotechnical and civil engineers, biologists, ecologists, geomorphologists, and foresters from North America, Europe, South-East Asia, Australia, and New Zealand. [ABSTRACT FROM AUTHOR]

This editorial describes a 25-paper special issue that began with a symposium at EcoSummit 2016 in Montpellier France in August/September 2016 with a focus on ecological engineering principles applied to the development of large-scale sustainable landscapes and catchments. The papers are divided into the following categories: watershed management (3 papers); wetland creation and restoration (5 papers); monitoring wetlands (3 papers); lake management (2 papers); restoration of wetland and terrestrial landscapes (6 papers); public health (2 papers); and ecotechnological solutions (4 papers). Some of these case studies are purposeful application of ecological engineering principles; others happened or are happening naturally through self-design. Several of the presentations focus on ecological engineering that involves scales of thousands of hectares or even larger catchments to solve ecological and environmental problems. Case studies are presented by scientists and engineering from North America, Europe, and South America. [ABSTRACT FROM AUTHOR]

Green roof is one of the main infrastructures used in Sustainable Urban Drainage Systems (SUDS). Detailed design and the correct choice of materials to be applied in this type of roof are essential to obtain satisfactory hydrological performance. In recent years, numerous papers on this topic have been published. This study aimed to provide a holistic view of the main research trends for the construction of green roofs to control stormwater runoff. A systematic literature review was carried out within scientific publications from the last 5 years in the Web of Science (WoS) database. 67 papers were selected for analysis. Recent types of vegetation and materials for green roofs were listed and hydrological tests were discussed in this review. Extensive substrates were chosen by 78% of the studies due to smaller thickness, tending to be lighter and economically viable than intensive substrates. Succulents of Sedum genus were the most used in the studies due to their physiological characteristics and ability to adapt to different climates. Drainage layer consisted mainly of specific slabs commercially available for green roofs. Other layers, such as filtration, thermoacoustic insulation, and waterproofing, were also applied in many studies. The main parameters to evaluate the hydrological performance were retention capacity and runoff coefficient. In general, results showed that green roofs have considerable capacity to reduce rainwater runoff. However, many factors, such as meteorological indices, substrate antecedent moisture, and materials and plant species used can influence hydrological performance of green roofs. Some gaps were found in studies. Most of them did not compare the performance of green roofs with conventional roofs. In addition, the studies did not present cost and weight analyses, which is very important for the decision to build green roofs. [ABSTRACT FROM AUTHOR]

Anthropogenic impacts on marine habitats are a global problem, particularly in coastal areas. While boulder reefs in temperate waters hold high biomass and biodiversity, and may be unable to recover from anthropogenic stressors without restoration efforts, little is known about how to restore and conserve this important marine habitat. Limited knowledge is a serious impediment to projects aimed at restoring boulder reefs that have been degraded or removed by substrate extraction. In 2008, a boulder reef was restored in Kattegat, the transitional waters between the North Sea and the Baltic Sea, using differently sized boulders. The restored reef covered approximately 27,600 m 2 seafloor and included 100,712 tons of boulders added at depths ranging between 4 and 11 m. This paper describes methodology and lessons learned during the restoration project. Before the restoration, geological and geotechnical surveys confirmed that the sea bed could support added boulders, and high resolution bathymetric surveys provided input for the design of the reef, particularly for numerical modelling of the hydrographic and sediment transport conditions. Numerical modelling was used to derive hydrographic design conditions for boulder placements and further, to ensure that the restored reef would not affect the sea bed morphology and hydrographic conditions at a local harbour and at a protected habitat, both situated in the vicinity of the restoration area. Data on the physical structure of the restored boulder reef, collected in 2009, demonstrated that cavernous structures and shallow reef areas were restored. Moreover, data collected in 2012 confirmed the stability of the restored reef. Finally, results highlighted the importance of stakeholder mapping at the outset, appropriate timing of stakeholder involvement and ongoing consideration of stakeholder perceptions. Charting strategy and introducing a checklist for marine restoration projects, this paper outlines important considerations and methodology needed to ensure that restoration of temperate reef structures meet the objectives, without having undesirable effects on existing hydrographic and morphological conditions, including nearby coastal areas and protected marine habitats. [ABSTRACT FROM AUTHOR]

An idea that which zones are the main disturbed areas in mining cities and what are the exact impacts in space concerns re-use and optimal allocation of land. Current research mostly concludes that mining activities impact land use greatly, but there is no definite spatial range of disturbance. To find out the exact range, this paper sets up 12 gradients composed of mineral locations and 11 surrounding gradients with an interval of 3 km. And the “D-C-S” (Disturbance-Continuity- Sustainability) framework was then established to evaluate land use characteristics, including 9 indices in the three layers of disturbance, continuity and sustainability. Here, this paper adopted two approaches − transverse land use profiles and anomalous economic points − to test out the understanding of land use characteristics in mining cities. Our findings show that the areas surrounding mineral locations possibly play a more important role in land use structure and functions, designated to 0–9 km, especially 3–6 km away from mineral locations, where land needs more concerns about optimal allocation for future policy-making to improve the pattern, function and continuity. [ABSTRACT FROM AUTHOR]

Due to the serious nitrate pollution in Northeast China, the in-stream nitrate and its isotopic composition (δ 15 N-NO 3 and δ 18 O-NO 3 ) were analyzed to explore the seasonal nitrate sources and its transformation processes combining with chemical indicators in the Haicheng River during the spring, early summer, late summer, and autumn seasons throughout the year of 2010. The nitrate nitrogen (NO 3 -N) concentrations in riverine water co-varied with the discharge data of the river, showing significant seasonal variations (p < 0.001) based on the one-way ANOVA. The riverine δ 15 N-NO 3 values and chloride (Cl − ) variations suggested that NO 3 -N was mainly contributed by sewage/manure in spring. The NO 3 -N sources in early summer were largely induced by nitrification process from synthetic fertilizers. The combined application of δ 15 N-NO 3 and δ 18 O-NO 3 explained that the NO 3 -N sources in late summer and autumn were derived largely from soil organic matter and sewage/manure. Denitrification process of soil organic matter and sewage/manure in autumn and their nitrification process in late summer mostly controlled the NO 3 -N concentrations in river water. The results will provide useful information on nitrate sources of seasonal variations in isotope compositions of river systems for controlling NO 3 -N concentrations and improving the ecological quality near the Liaodong Bay and Bohai Sea in the near future. [ABSTRACT FROM AUTHOR]

Understanding the relationship between supply and demand of ecosystem services (ES) is important to achieve sustainable use of natural capital and keep coordination of supply and demand. This paper used spatial analysis of the Geographic Information Science (GIS) method to quantify ecosystem service supply (ESS) and ecosystem service demand (ESD) by constructing the ecosystem services provision index and land development index respectively. Then the spatial-temporal characteristics of ES's supply and demand situation in Hexi Corridor (HC) were analyzed. In addition, the ecosystem service flow (ESF) and the corresponding ecological compensation (EC) for the ecosystem services supply areas (ESSA) and ecosystem services demand areas (ESDA) were quantified. The results showed that the regions with medium and high ESS showed significant growth, and regions with high ESD increase significantly. Besides, the distribution pattern of the ecosystem services supply-demand ratio (ESSDR) was high in the northwest and low in the southeast, which was mainly dominated by ES surplus, and the ESSDR always has spatial autocorrelation and spatial heterogeneity, forming a relatively stable spatial pattern. The High-High cluster areas of ESSDR were mainly distributed in the better ecological area, while the Low-Low cluster was mainly distributed in the economic development area. The supply-demand coordination displayed a balanced trend, and the changing area of supply-demand was mainly concentrated in the population aggregation region in the south of HC. The EC amount paid by ESDA decreased from 2000 to 2020, indicating that the supply capacity of ES was increased. This paper can provide references for regional ecosystem management and restoration. [ABSTRACT FROM AUTHOR]

In this special issue, a number of the latest and meaningful research related to riverine wetlands from a variety of fields were presented and discussed, covering investigation and analysis of many studying sites, development of ecosystem service evaluation approaches, propose of ecosystems modeling methods, advancement of wetland restoration and protection techniques and strategies, as well as the applications of these methods and models in several typical wetlands and the associated river systems. In this special issue, 24 papers were selected for a thorough peer review process with at least two rounds of reviews. According to the journal's guideline and requirement, the 24 papers were reviewed by at least two authoritative experts in this field. All papers were related to the topic of “Function, Restoration, and Ecosystem Services of Riverine Wetlands in the Temperate Zone,” offering a good view of relevant issues and research status, techniques, and applications for restoration. The 24 papers can be categorized into four groups: (a) investigation and evaluation of ecosystem services and functions, (b) dynamic modeling and optimal management of ecosystem services, (c) policies and technologies for ecosystem restoration, and (d) practices and application of ecosystems modeling and restoration approaches. [ABSTRACT FROM AUTHOR]

MIKE SHE is one of the most extensively used physically based distributed hydrological models that are capable of credibly interpreting the response mechanism of ecohydrological processes to ecosystem components and organization. However, implementing MIKE SHE in integrated catchment modeling is a complex task requiring an experienced modeling team with skills in a variety of disciplines, making it difficult for scientists without a background in hydrology or computer science to utilize this useful model. This review, from the perspective of ecology and environmental science, illustrates the important role of a physically based distributed model as a solution to issues related to ecohydrological processes, offering a major discussion of issues that received little attention from the previous reviewers and that would interest researchers without a hydrology background. The inevitable and possible difficulties confronting these potential users at the beginning and early stages of utilizing the model are also brought to light, with suggestions for solutions. This paper offers a brief review of MIKE SHE development and elaborates its main merits, key problems, and research on the model's theories and practices implemented by scholars. Lingering problems in current solutions are analyzed, and potential approaches to solutions are proposed. We hope that this paper provides some practical advice to researchers who want to initiate study of water issues related to modeling ecohydrological processes by employing MIKE SHE. [ABSTRACT FROM AUTHOR]

Nitrate pollution of surface water from farms and urban runoff is widespread – impairing drinking water supplies, recreation, and wildlife habitat. The scale of the problem in rivers has overwhelmed most watershed-based best management practices. A new paradigm is needed. In this paper we highlight the 119 ha (294 acres) Prado Wetlands in southern California, USA as an example of a gravity-enabled, free surface flow vegetated wetlands to treat a river – the nitrate-rich, effluent-dominated Santa Anna River. The wetland treats ∼1–2 m3/s of the 7.1 m3/s (250 cfs) flow of the river in 28 wetland cells in two parallel trains (residence time 2–4 d, hydraulic loading rate 10–20 cm/d). The cleaner water is returned to the river and infiltrated downstream into a managed groundwater basin supplying 2.4 million customers. Since 1998, ∼1200 t of nitrate-N have been permanently removed from the river and released as N 2 -gas into the air. Over 24 years, in the warm summers an average of 6.1 mg-N/L entered the wetland and 3.7 mg-N/L flowed out, a removal efficiency of 57%. In the cooler winters, an average of 6.4 mg NO 3 -N/L entered and 2.6 mg NO 3 -N/L flowed out, a removal efficiency of 45%. Individual months varied widely in concentration removal efficiency from 7% (winter) to 98% (high summer). Areal summer removal averaged 137 mg NO 3 -N/m2/d and the apparent "k" was around 46 m/y. All-year rates were 129 mg NO 3 -N/m2/d or 47 g/m2/y, a reasonable performance considering the size of the system and its configuration for both nitrate removal and duck hunting (i.e., more open water). Annual average nitrate removal efficiency increased substantially over time (45 to 72% for 1998–2004 versus 2016–22) and is attributed to an increase in hydraulic residence time, upgraded internal plumbing, and increased winter temperatures (+3C°). Prado Wetlands also removes phosphorus, though not as well as nitrate; average warm season removal efficiency was 23% (inflow 1.20 mg PO 4 -P/L, outflow 0.93 mg PO 4 -P/L). The aerial removal rate was high at 23 mg P/m2/d or 8.5 g/y, probably due to the high inflowing P-concentrations and the hard water. Wildlife was also enhanced. Least Bell's Vireo (Vireo belli pusillus) , an endangered bird in the Prado Basin, increased from 19 pairs (1998) to a recent average of 444 pairs due to habitat improvement and reduction of cowbird parasitism. Results from the Prado Wetlands show that cleaning up rivers via diversion through wetlands benefits both water quality and wildlife. [ABSTRACT FROM AUTHOR]

Most lacustrine deltas are nowadays highly anthropized systems. River training works during past centuries considered rivers mainly as vectors of water and sediments from a point source to a sink. However, numerous problems have been identified by residents and the competent authorities, such as lakeshore erosion near river deltas, land-use conflicts, and loss of biodiversity without efficiently managing flood risks. These human-induced changes on the deltaic environment led to the deterioration of ecosystem services. This paper focuses on the lacustrine deltas as a complex biotope at the interface of aquatic and terrestrial environments. It proposes a restoration strategy based on two simple geometrical parameters. This methodological approach defines the potential to recover a quasi-natural state of the delta using the slope of the upstream water course and the opening angle of the delta. The result of this work is the creation of a diagram like the ones classifying rivers according to their morphology. This chart will allow the design engineer to determine, given the actual slope of the water course, which shape a delta would ideally adopt without accounting for the downstream lacustrine morphogenic parameters. It will also help in determining the space required for the watercourse to fulfill its natural functions. This methodological approach is applied to a case study: The Reuss Delta, where a restoration project took place. This approach can be used as a pre-study to determine, according to the available space, if it will be possible to improve the morphological dynamics of the delta and to recover its non-anthropized state. [ABSTRACT FROM AUTHOR]

In this proof of concept paper, we address the potential role of forests and vegetation cover as an adaptation tool. In contrast to work addressing the carbon benefits of afforestation, we highlight the potential usefulness of forests as major contributors to the water cycle. Integrating water and carbon cycle benefits into a common objective enhances discussions about the role and value of forests. Herein, we describe a method for increasing regional precipitation in semi-arid environments, thereby potentially helping to increase scarce water resources. The approach capitalizes on observed interactions between forest cover and the hydrologic cycle, with the express aim of returning much needed water resources to an increasingly vulnerable region. The natural processes behind “precipitation recycling” (PR), and vegetation based cross continental transport of atmospheric moisture form the core of this solution. Induced precipitation recycling (IPR) initiates these processes by irrigating afforested land using locally available surplus water. This paper discusses the underlying processes and a proposed demonstration project that functions as both a “proof of concept” and a research testing ground, providing potential validation for promoting future expansion to the wider region. The proposed IPR project utilizes treated wastewater and surplus storm run-off, thus averting additional burdens on the existing water supply, while performing additionally valuable environmental and ecosystem services. IPR provides an alternative approach to supplement existing and typically far costlier plans to address regional water shortages and handle wastewater treatment. The proposed integrated solution would not only contribute positively to regional water supply, but would also provide additional eco-system services and end-products that add value and utility, thereby improving the project’s potential economic viability. This project should be of particular interest to land use and water management planners in the Los Angeles Basin area for whom it is conceived, as well as to those along much of the coastal region in California where climate change-driven drought cycles have been increasing in length and intensity. [ABSTRACT FROM AUTHOR]

This paper acquaints readers with outputs produced from thematic maps and analytical testing in a land consolidation project which is being conducted in Slovakia at the Žitava River basin (1.628-square-kilometres total watershed). New options and strategies are presented for the use of a land consolidation database for projects in any planning, optimizing and development activity to be performed by any expert who enters the model area with her/his own opinions. We highlight problems currently limiting rural development (the area's low ecological stability, frequent floods, ever greater soil erosion, etc.) and also describe measures which could protect the area against natural disasters (e.g. ongoing water erosion, silt accumulating and choking streams and water expanses). The paper introduces methodical procedures that enable a functional organization of the area to be designed (calculating ecological stability, determining critical points and a methodology for determining the degree of erosion in endangered areas, etc.). It also analyses conditions in relation to protecting and developing the rural region, highlighting the chief problems in water management, access to roads and environmental protection, while graphically presenting basic thematic layers crucial for assessment. Based on this data set, a broad portfolio of combinations can be utilized for evaluating the quality of the proposed measures. We suggest a new combination of methods to let system users determine what measures should be recommended for cadastral plots. Examples are presented of changes affecting the structure of the landscape, the threat of erosion, elimination of flood conditions and the quality of life in the model area. [ABSTRACT FROM AUTHOR]

Changsha–Zhuzhou–Xiangtan is an urban agglomeration along the middle reaches of the Yangtze River, the development plan of which is listed as one of national strategic development. The eco-environmental quality of the Changsha–Zhuzhou–Xiangtan urban agglomeration concerns the ecological security of China. It is essential to discuss the method of creating urban agglomeration plans to increase ecological security. In this paper, the ecosystem distributions were mapped using the CLUE-S model incorporated with Gray Model (GM) (1, 1) and an auto-logistic regression model under the conditions of a natural increase scenario (NIS), a cultivated protection scenario (CPS) and an ecological protection scenario (EPS). We analyzed the change and conversion characteristics of ecosystems both in the study area and the junction of Changsha, Zhuzhou and Xiangtan. The results showed that the ecosystem change model developed in this paper performed well in mapping future urban ecosystem distributions. The change of the ecosystem spatial distributions showed us that the built-up ecosystem would expand in the future by transforming cultivated and green land ecosystems and that the boundaries between cities would be blurred. In the whole study area, the amount of converted area from cultivated and green land to built-up land was lower in CPS and EPS than in NIS. However, in the key area, the converted result was contrary to the whole study area. Although the CPS and EPS were beneficial to the eco-environmental protection of the whole study region, the sub-regional eco-environment should be given more attention to assure that the ecological security of the whole region remains safe. [ABSTRACT FROM AUTHOR]

This paper is dedicated to numerical analysis of the influence of vegetation on slope's stability using the calculation of the safety factor of different slopes by a classical shear reduction method with the software PLAXIS in 2D. The soil is modelled as an elastic perfectly plastic material. The shear strength of the soil is also modelled using the Mohr–Coulomb criterion. Slope stability is influenced by vegetation mechanical parameters: plant's root matrix system and surcharge due to presence of trees. Based on 2D finite element method, this paper investigates the combined effects of different rectilinear slope geometries, soil types and vegetation mechanical parameters on the slope's factor of safety. The effects of the roots are modelled by increasing the soil cohesion following a classical Wu model. The additional cohesion depends on the vegetation type and on the depth from soil surface. The analysis examined reinforcement effects of the roots’ systems of four idealised types of vegetation growing on three different types of soil composing the slope. The case study was performed on different slope configurations where slope's height and angle were allowed to vary significantly. Two key parameters of the root matrix system had been considered for the finite element analysis: additional cohesion due to the presence of roots and depth of the root matrix. Moreover, influence of geometrical parameters, height and angle of the slope, on the stability of different slope configurations had been analysed by computing slope's factor of safety. Parametric studies were performed to assess the variation of the factor of safety of a slope in case of different geometrical configurations combined with several types of vegetation coverage. Results showed that the slope angle had the greatest impact on variation of factor of safety. Additional cohesion is regarded as the second most important parameter influencing the factor of safety. These two parameters combined play an important role in shallow failures of slopes and significantly affect stability of a slope regardless of a soil type composing the slope. Results of the current study can help practitioners determine if a slope is at risk by the lack of additional roots cohesion combined with different types of soil and young vegetation. Hence, the proposed method helps evaluate slope's vulnerability and could be efficiently used as management or informative tool for ecological engineers and forest conservative practitioners. [ABSTRACT FROM AUTHOR]

India with 2.4% of total global land area is home for about 8% of global biological diversity. In providing goods and services to 18% of world's human population this megadiverse country is losing its biological wealth at an alarming rate. The degradation of terrestrial (forests, grasslands, agriculture, etc.) and aquatic (small to large fresh and marine water bodies) ecosystems has been the key factor in accelerating this irreversible and unrepairable loss. Although ecosystem restoration targets are well reflected in various programs and policies of India, the scientific insights and preparedness on this topic and critical analysis of this knowledge to guide policy initiatives for ecosystem restoration was lacking. Therefore, this editorial paper reviewed 22 papers, published in special issue on ' Ecological Restoration of Degraded Ecosystems in India: Science and Practices ' in Ecological Engineering journal, to analyse the scientific knowledge to inform policy and practices towards achieving ecosystem restoration goals in India (https://www.sciencedirect.com/journal/ecological-engineering/special-issue/109W0PCNQBM). Most studies in this special issue focus on providing solutions for restoration of different degraded ecosystems. A few of them are solving the dilemma of native and non-native species selection for reforestation and afforestation activities. One study provides insights on management of an invasive species in grassland ecosystems. Three studies suggest adopting conservation agriculture practices to enhance agricultural biodiversity, carbon sequestration and socio-economic benefits for marginal farmers. Two out of five papers dealing with aquatic ecosystems provide a framework to quantify the magnitude of degradation, other two propose restoration technologies for coastal zones on India and one assessing the effectiveness of relocating collar reef from degraded urban coasts to reference coastal sites. • Twenty-two papers published in a special issue are reviewed here. • Papers cover terrestrial and aquatic ecosystem restoration studies from India. • 87% papers provide pragmatic solutions for restoration of degraded ecosystems. • Timely collection on scientific preparedness of India for ecosystem restoration. [ABSTRACT FROM AUTHOR]

Ecological restoration has been risen to a national strategic project for China and become an significant way to realize ecological civilization construction. As an important way to measure the effectiveness of ecological restoration engineering, the corresponding evaluation provides a reliable basis for ecological restoration decision-making and ecosystem management. Based on remote sensing technology with the advantages of short revisit time, large monitoring range, high spatial resolution, this paper proposes a remote sensing evaluation method of watershed ecological restoration effect, so as to monitor the implementation effect of ecological restoration engineering in the watershed and technically check whether the expected goals set before the restoration are achieved. The comprehensive ecological restoration engineering of Yongding River has been implemented since 2016, and it was the first focus of the coordinated development of Beijing-Tianjin-Hebei region to make advances in ecology. In this paper, year 2015 and 2020 were selected as the before and the after the ecological restoration engineering of Yongding River. The research object was the riparian zone from Luopoling Reservoir to Daning Reservoir in Yongding River Watershed. After obtaining and processing remote sensing images, ZY-3 images were used to obtain land cover data by means of human-computer interactive interpretation, and Landsat images were used to retrieve NDVI data. Based on these data, the changes of the eight indicators of water resources, water ecology and ecological function in the study area were calculated to evaluate the ecological restoration engineering effect. The results showed that the study area has basically realized the maintenance of ecological water quantity, formed the ecological corridor of Yongding River, and effectively enhanced the ecological function and improved the water environment. By verifying the feasibility of remote sensing evaluation method, this paper could provide relevant decision makers and planners with an effective evaluation method for the ecological restoration engineering effect based on remote sensing data and technology. • Remote sensing images and land cover data were utilized to calculate the indicators before and after ecological restoration. • Ecological restoration engineering effect was evaluated from water resources, water environment and ecological function. • Based on the proposed method, the ecological restoration effect in the study area was proved to be satisfactory overall. [ABSTRACT FROM AUTHOR]

Soil applicable biochar has been prepared from bark of Leucaena leucocephala wood which is a waste generated during its pulping and papermaking process. The slow pyrolysis process adopted for this purpose has been modelled and optimized employing central composite design and desirability function under response surface methodology taking temperature (308–592 °C) and time (35–205 min) as independent variable while yield, loss on ignition, stable organic matter, oxidisable carbon and carbon liability index as dependent variable. L. leucocephala bark was characterized in terms of proximate analysis (moisture 4.90%, ash 7.20%, fixed carbon 18.10%, volatile matter 69.80%), elemental analysis (carbon 45.78%, hydrogen 10.67%, nitrogen 1.77%, oxygen 32.08%, sulphur 0.09%), lignocellulosic composition (holocellulose 45.86%, hemicellulose 15.01%, lignin 34.75%) and compared with a wide range of feedstocks to find its suitability towards biochar production. The optimum pyrolysis temperature and residence time were found to be 350 °C and 60 min respectively which gave biochar yield 53.16%, loss on ignition 88.17%, oxidisable carbon 28.82%, stable organic matter 38.48%, and carbon liability index 0.32. The biochar produced at optimum conditions were characterized by proximate analysis (moisture 0.65%, ash 11.83%, fixed carbon 40.2%, volatile matter 47.57%) and elemental analysis (carbon 62.91%, hydrogen 3.12%, nitrogen 2.65%, oxygen 20.74%, sulphur 0.05%). The O/C ratio of 0.25 and H/C ratio of 0.60 confirmed its life between 100–1000 years and appropriateness for soil application as well as carbon sequestration. [ABSTRACT FROM AUTHOR]

Human-altered flow regime is often claimed to be one of the most serious and continuing threats to aquatic biodiversity in streams and rivers. It is commonly found that both seasonal and subdaily flow patterns are changed below hydropeaking dams due to the multifunctions of the reservoirs such as flood control and water supply. The aim of this paper is to comprehensively quantify the degree of ecologically relevant hydrologic alteration downstream of Gangkouwan Reservoir, focusing particularly on the subdaily flow variation induced by hydropeaking operations. The method is based on the assessment framework set by the indicators of hydrologic alteration (IHA). Hydrologic parameters in groups 1–3 of the IHA were adopted to assess the degree of hydrologic alteration at daily to monthly time scales and based on a daily mean flow data series for both the pre- and post-impact periods. A set of biologically relevant hydrologic parameters based on post-dam hourly flow data, including magnitude and duration of baseflow, magnitude and duration of peaking flows, frequency of peaking flows and ramping rates, were proposed to depict subdaily flow pulses and water condition changes induced by hydropeaking. The results show that Gangkouwan Reservoir made the intra-annual distribution of runoff more consistent, reduced annual peak discharges, and changed the timing of the yearly maximum. The monthly distribution of these hydrologic parameters at the hourly temporal scale provides detailed information on ecologically significant features of the subdaily flow variation induced by hydropeaking operations. This paper provides useful guidance for further investigations on responses of river biota to hydropeaking and provides guidance for suggesting mitigation measures against hydropeaking effects. [ABSTRACT FROM AUTHOR]

Beitang is an ecologically engineered constructed wetland dominated by human activities and is composed of paddy fields, ponds, ditches, courtyards and other related ecological infrastructure with the functions of agricultural production, hydrological regulation, environmental cleanup and ecological agricultural regulation. The history of Beitang extends back more than 2500 years in China, and it plays a very important role in China's agricultural development. This paper first reviews the history of the development of Beitang; then according to the historical structural features of Beitang, it summarizes Beitang as a pond–ditch–courtyard–farmland ecological engineering composed of constructed breakwaters, sluice gates, and water intakes; courtyards; and farmland and irrigation ditches with the functions of water collection, storage and conveyance. Under different terrain conditions, Beitangs exhibit different characteristics. For example, in flat areas featuring a larger pond capacity, longer shoreline and larger area of farmland, a Beitang can serve more rural areas; in hilly areas featuring a smaller pond capacity and smaller area of farmland, ditches serve as a very important structural unit that can connect ponds for water volume regulation between ponds, increase the irrigated area, and achieve gravity irrigation to as great an extent as possible. Moreover, the paper analyzes the hydrological, nutrient cycling and biological processes as well as other ecological processes associated with this type of pond–ditch–courtyard–farmland-system. The paper also proposes five ecosystem services of Beitang: hydrological regulation, ecological purification, soil and water conservation, production functions and biological diversity protection. Finally, the paper analyzes the reasons for the degradation of Beitang over the past 30 years from the perspectives of institutions, management, concepts and technology, and proposes corresponding countermeasures to protect and restore Beitang. [ABSTRACT FROM AUTHOR]

The experiment was conducted to evaluate the role of vermicompost as strong buffer and natural adsorbent to reduce the transition metals, BOD, COD, total dissolved solids (TDS) and total suspended solid (TSS) under laboratory condition from three industrial effluent viz. beverage, distillery and paper mill. Adsorbent (vermicompost) prepared from cow dung with the help of exotic earthworm Eisenia fetida was used in a glass column reactor (38 cm × 3.2 cm i.d). The effluents were passed through the different amount of vermicompost (20 g, 50 g and 100 g) with particle size upto 230 μm. The maximum adsorption capacity was studied by applying the linear Langmuir and Freundlich isotherm model. The maximum adsorption was noticed for Cu and the least for Zn. Freundlich adsorption isotherm was best fitted for Cu in distillery effluent ( n = 4.25) followed by Mn in beverage, paper mill and distillery effluent ( n = 5.81, 4.95 and 7.75 respectively), Fe and Zn in beverage industry ( n = 2.31 and 7.01). Vermicompost act as a strong buffer to neutralize the pH of the effluent. The pH of the filtrate came to be 7.8 for beverage and paper mill effluent and 5.8 for distillery effluent. EC of the filtrate increased to 4.0 mS/cm for beverage effluent, 6.1 mS/cm for paper mill effluent and 8.1 mS/cm for distillery effluent from its initial value of 2.0, 4.8 and 6.9 mS/cm respectively. The value of COD was 2.5 times less than their respective initial values. Vermicompost removed the high BOD of the industrial effluents and it came down to 174.0 mg/L for beverage industry, 260.0 mg/L for paper mill effluent and 5806.0 mg/L for distillery effluent from its initial value of 387.5 mg/L, l440.0 mg/L and 17200.0 mg/L respectively. TDS and TSS of the effluents respectively came down to 72.0 mg/L and 246.0 mg/L for beverage effluent, 210.0 mg/L and 230.0 mg/L for paper mill effluent and 206.7 mg/L and 105.7 mg/L for distillery effluent. [ABSTRACT FROM AUTHOR]

Constructed wetlands have been used for wastewater treatment for more than fifty years. Most applications have been designed to treat municipal or domestic wastewater but at present, constructed wetlands are successfully applied to many types of wastewater. The early constructed wetlands applied to industrial wastewaters included those for wastewaters from petrochemical, abattoir, meat processing, dairy and pulp and paper industries. During the 1990s constructed wetlands were also used to treat effluents from textile and wine industries or water from recirculating fish and shrimp aquacultures. The most recent applications include those for brewery or tannery wastewaters as well as olive mills effluents. The survey revealed that both subsurface and surface flow constructed wetlands have been used for treatment of industrial wastewaters. Within subsurface flow constructed wetlands both horizontal and vertical flow systems have been designed. Also, the use of various hybrid constructed wetlands for industrial effluent treatment has been reported in the literature recently. The survey also revealed that industrial wastewaters are treated in constructed wetlands in all continents and this paper includes the information from 138 constructed wetlands in 33 countries worldwide. [ABSTRACT FROM AUTHOR]

Maturation (polishing) ponds operating after UASB (upflow anaerobic sludge blanket) reactors are considered a highly suitable system for treating domestic sewage for small to medium communities in warm-climate developing countries. Important attributes are operational simplicity, good organic matter and nitrogen removal, excellent pathogen removal and lower land requirements compared to traditional pond systems. However, most papers in the literature focus on single studies investigating one particular aspect of this system. The objective of the current paper is to present a broad evaluation of one particular system (UASB reactor, three shallow ponds and a coarse rock filter in series) in Brazil treating sewage from 250 inhabitants over a period of 10 years. The study covers in an integrated manner the removal and behaviour of several variables, such as organic matter (BOD and COD), solids, nitrogen fractions, phosphorus, coliforms, pathogenic bacteria, helminth eggs, sulphides, surfactants and organic micropollutants (diethylphthalate, bis(2ethylhexyl)phthalate and bisphenol A). Even with short hydraulic retention times in each pond (2 to 6 days), the results endorse the good capacity for organic matter and ammonia removal and excellent removal of coliforms, helminth eggs and sulphides. Removal of phosphorus, surfactants and selected micropollutants was limited. [ABSTRACT FROM AUTHOR]

Urban runoff can impact the thermal regime of surface waters and degrade valuable aquatic ecosystems. Some stormwater control measures (SCMs) have been shown to mitigate the effects of thermally-enriched runoff, but previous studies lacked consistency when characterizing the thermal behavior of SCMs. Ecologically-relevant parameters such as maximum outflow temperature, duration of temperatures exceeding thresholds for coldwater species, and thermal load have all been considered in past research. Standard metrics that properly represent the downstream impacts of urban stormwater were needed. This paper evaluated thermal metrics to provide designers and regulators with catchment-scale methods for assessing thermal performance and compliance. It was concluded that multiple metrics must be employed to account for both thermal load and biologically-based reference temperature limits. Metrics for temperature evaluations were broken out by data requirements. When only SCM temperature data are available, event mean temperature estimation appears to be the most rigorous metric. Groundwater temperature may also be employed as a surrogate metric for SCM discharge temperatures if conservative protection of coldwater stream health is desired. When SCM temperature and flow data exist, thermal load reductions should be explored. Efficacy of the low impact development (LID) strategy for temperature mitigation (retaining onsite greater than the 95th percentile storm event) was evaluated using field-collected permeable pavement data. Based on these data, retaining the 95th percentile storm event was determined to be an effective technique for thermal protection of surface waters. However, the most rigorous metrics involve long-term temperature and flow data from local reference streams. The best metric currently available is the uniform continuous above threshold (UCAT) method, in which it is necessary to consider continuous exposure duration when comparing against biological thresholds. These analyses can be tailored to specific species of interest within a targeted ecoregion. Combined with thermal load and mixing analysis in-stream, the UCAT method can provide a real-world estimation of the impacts of development. Additionally, evaluation of mixing zones in-stream should also be employed to adequately assess thermal impacts. However, these methods are the most data intensive. The metrics discussed in this paper can be used to inform new and existing design methodologies for regulating stormwater temperature, duration, and thermal load. [ABSTRACT FROM AUTHOR]