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[Display omitted] The pulp and paper sectors are thriving yet pose significant environmental threats to water bodies, mainly due to the substantial release of pollutants. Lignin-derived compounds are among the most problematic of these contaminants. To address this issue, we present our initial results on utilizing organic semiconductor photocatalysis under visible light for treating lignin-derived compounds. Our investigation has been centered around creating a green and cost-effective organic semiconductor photocatalyst. This catalyst is designed using a structure of bagasse cellulose spheres to support PM6 (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo[1,2- b :4,5- b' ]dithiophene))– co -(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)-benzo[1,2- c :4,5- c' ]dithiophene-4,8-dione))]: MeIC (3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-cyclopentane-1,3-dione[ c ]-1-methyl-thiophe))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3- d:2′ , 3′-d' ]-s-indaceno[1,2- b :5,6- b' ]-dithiophene)). This photocatalyst demonstrates remarkable efficiency, achieving over 91 % degradation of lignin-derived compounds. The superior photocatalytic performance is attributed to three main factors: (1) The ability of PM6 to broaden MeIC's absorption range from 300 to 800 nm, allowing for effective utilization of visible light; (2) the synergistic interaction between PM6 and MeIC, which ensures compatible energy levels and a vast, evenly spread surface area, promoting charge mobility and extensive donor/acceptor interfaces. This synergy significantly enhances the generation and transport of carriers, resulting in a high production of free radicals that accelerate the decomposition of organic materials; (3) The deployment of PM6:MeIC on biomass-based carriers increases the interaction surface with the organic substances. Notably, PM6: MeIC showcases outstanding durability, with its degradation efficiency remaining between 84 % and 91 % across 100 cycles. This study presents a promising approach for designing advanced photocatalysts aimed at degrading common pollutants in papermaking wastewater. [ABSTRACT FROM AUTHOR]

Water hyacinth (WH) is considered as the worst aquatic weed in the world because of its rapid growth and fast spread into new areas of fresh water bodies. We investigated the potentiality of using WH as a raw material for production of handmade paper and compost in Bangladesh. Potash pulping was done using potassium hydroxide (KOH) at different alkali concentrations (8–12%) with a liquor to solid ratio of 7:1 at 145 °C for 2 h. The pulp was bleached using hydrogen peroxide (H 2 O 2), and pulp properties (brightness, tear index and tensile index) of bleached and unbleached pulps were analyzed following the respective TAPPI standards. The produced black liquor was mixed with WH along with kitchen bio-wastes to produce compost. The properties of the compost were tested following the published protocols, i.e., wet digestion, Kjeldahl, vanadomolybdophosphoric acid, and Flame Spectrophotometry methods. Brightness, tensile index and tear index of bleached hand sheets were found to be 37.2%, 49.2 N m/g and 6.79 m.Nm2/g, respectively suggesting significant contribution of bleaching on WH paper quality. Addition of black liquor significantly increased the nitrogen and potassium content of bio-waste compost. Thus, WH can be used as a raw material for making handmade paper while the process by-product can be supplemented to improve the nutritional quality of compost. Such cottage-industry fabrication of WH green products could be developed to control the infestation of WH in water bodies, and this technology may provide for new possible sustainable livelihood option. [Display omitted] • Handmade paper was produced from water hyacinth (WH) using the KOH pulping method. • The waste potassium-rich black liquor was used to produce compost mainly from WH. • H 2 O 2 -bleached WH pulp showed better strength properties. • The produced compost was rich in macronutrients, i.e., N and K essential for plant growth. [ABSTRACT FROM AUTHOR]

This study has carried out a systematic review of 36 scientific papers (reporting 63 case studies) published in the last 15 years about the treatment of industrial, agri-food and municipal wastewater in lagoons. A concentration of studies from a few countries (Italy, Algeria and Iran) and about municipal wastewater (70% of papers) was revealed by the bibliographic analysis. Aeration was supplied in more than 50% of case studies; the storage capacity of lagoons (adopted as a measure of size) was extremely variable (over seven orders of magnitude), while their depth was generally lower than a few metres. The efficiency of lagoon treatments at removing COD was in a wide range (25–98%). Very few studies analysed the energy intensity of treatments in lagoons. The meta-analysis applied to a further selection of 10 papers with 29 case studies revealed significant differences in pH and dissolved oxygen concentration, due to aeration or type of treated wastewater. Treatment efficiency was higher in aerated lagoons compared to non-aerated systems, and did not depend on the type of treated wastewater. Based on the analysis of the reviewed papers, an urgent research need on this topic arises, mainly due to the oldness of most analysed studies. Practical suggestions are given to optimise the depuration performances of lagoons: (i) application of intermittent and night aeration; (ii) reduced air flow rates; (iii) adaptation of microbial biomass to high contents of inhibiting compounds in wastewater; (iv) construction of baffles to keep the planned hydraulic retention time avoiding short-circuit; (v) integration of lagoons with other treatments (e.g., constructed wetlands); (vi) ferti-irrigation of crops with lagoon effluents rather than disposal into water bodies. • A systematic review of 36 scientific papers (reporting 63 case studies) is presented. • The efficiency of lagoons at removing organic compounds was in a wide range (25–98%). • Treatment efficiency was higher in aerated lagoons compared to non-aerated systems. • This efficiency did not depend on the type of treated wastewater. • Practical suggestions are given to optimise the depuration performances of lagoons. [ABSTRACT FROM AUTHOR]

Water quality standards are instrumental in evaluating the status of water bodies, and in providing protective and restorative endpoints. To date, much of the infrastructure used to implement water quality standards has been directed towards remediating and managing pollution from point source discharges. However, pollution from diffuse sources is the leading cause of water quality impairment, especially by nutrients. Although the effects of nutrient enrichment on streams is well studied, and ecological thresholds identified, those thresholds have not been widely adopted as standards primarily because they are not attainable by point sources. Clearly, a framework for adopting and applying standards to manage pollution from diffuse sources needs to be decoupled from those intended for point sources. This paper argues for a relatively unstructured distributional approach to predict how ecological responses might shift in response to management of diffuse sources. The approach calls for first developing a deterministic model of stressor and response variables, followed by a reformulation as a Bayesian model. In the case here, a structural equation model was developed that linked nutrient enrichment, habitat quality, and chloride and manganese concentrations to an index of macroinvertebrate quality. Results from the Bayesian representation suggest that in landscapes where the drainage network has been highly modified for agricultural production, reduction in total phosphorus alone is expected to have a modest (but non-trivial) effect on macroinvertebrate condition, shifting the distribution of scores up by 1 point. The addition of habitat restoration is likely to shift the distribution upwards by 4 points, an effect size observed in Ohio, USA from other large-scale restoration efforts. [Display omitted] • Pollution from diffuse sources is now the leading cause of water quality impairment across the USA. • Water quality targets intended to manage diffuse pollution are likely to be more stringent than what is feasible for wastewater treatment plants. • This paper describes how Bayesian models can be used to assess water quality targets used in managing pollution from diffuse sources. [ABSTRACT FROM AUTHOR]

With the aggravation of global warming and the increasing demand for energy, the development of renewable energy is imminent. Floating photovoltaic (FPV) is a new form of renewable energy generation. However, the impact of FPV on the aquatic environment is still unclear. By long-term empirical monitoring and data analysis, this paper reveals the shading effect of large-scale FPV power station on aquatic environment for the first time. The results show that: (1) Compared with the non-photovoltaic (NP) zone, FPV only significantly reduces the concentration of dissolved oxygen in the photovoltaic (P) zone. (2) The concentration of chlorophyll a , nitrate nitrogen and total phosphorus increase, while pH and ammonia nitrogen decrease. FPV only causes an effect of the same order of magnitude as the initial concentration, and has no significant adverse effects on the nutritional status of the water body at a coverage ratio less than 50%. (3) FPV has a cooling effect on the water body during the daytime and a thermal insulation effect at night, with the most pronounced impact on peak water temperature (T w). The heating and cooling process of T w in P zone usually lags behind the NP zone by 1–3 h. The diurnal fluctuation and vertical difference of T w as well as the stability of water body are reduced under the shading of FPV, alleviating the influence of climate change on T w and water body stratification. (4) If 10% of the water area larger than 1 km2 in China are used to develop FPV, more than 900 million tons of CO 2 emissions can be reduced, and about 5 billion m3 water can be saved, which is significant in the context of climate change. In general, this paper provides a reference for the future aquatic environmental impact assessment of FPV and the formulation of related policies. • The impact of FPV on aquatic environment has been assessed. • The scale effect of FPV and impact of "fish-photovoltaic integration" are revealed. • Spatial-temporal and object specificity of impact on aquatic environment is reviewed. • The responds of FPV to the challenges of global climate change are further discussed. [ABSTRACT FROM AUTHOR]

Climate warming impact on excessive nitrogen (N) load in sediment favours cyanobacterial blooms in eutrophic waters. The nitrate (NO 3 −-N) and ammonium (NH 4 +-N) are two forms of N loads that contribute to algae blooms. However, little attention is paid to the impact of environmental factors on N loads variations at different time scales. This paper used a well-calibrated and validated EFDC model to investigate the temporal patterns and trends of ammonium and nitrate from June 2016 to June 2017. This paper presented the relationship and effects between these variations and environmental factors using data from satellite and reanalysis-based observations obtained for six meteorological parameters. The relationship and effects between these variations and environmental factors were also examined at different timescales (i.e., daily, monthly and seasonal scales). Model calibration results indicated that measured values reasonably matched simulated values. T he validation results revealed that relative error (RE) values were within an acceptable range. The REs of ammonium at East Taihu (S12) and Xu Lake (S23) sampling sites were 55.83% and 57.61%, while that of nitrate was 24.37% (S12) and 41.08%, respectively. The daily analysis of NH 4 +-N and NO 3 −-N variations was 7.318 ± 3.876 (g/m2/day) and 0.0275 ± 0.222 (g/m2/day), respectively. The monthly analysis showed NH 4 +-N and NO 3 −N range from 2.04 to 12.04 (g/m2/day) and 0.0008 to 0.064 (g/m2/day), respectively. The magnitude NH 4 +-N and NO 3 −-N varied and showed distinct inter-monthly variations. , The relationship between sediment fluxes and meteorological parameters showed the magnitude of correlation coefficient (r) and strength of correlation varied significantly. At daily scales, the relationship of NH 4 +-N and NO 3 −-N had a significant positive correlation with all meteorological parameters. At monthly, the correlation coefficient (r) of NH 4 +-N and NO 3 −N were heterogenous. At daily and monthly scales, air temperature and wind speed are the main drivers affecting sediment N loads' dynamics; however, the influence of relative humidity, precipitation, and evaporation on N loads are smaller. The study demonstrates the contribution of meteorological conditions to the magnitude and timing of N loadings variability in water bodies. The findings provide more insight into lake ecosystem protection and environmental remediation. [Display omitted] • The simulated nitrate and ammonium nitrogen were calibrated and validated with field observation data. • The driving factors influencing nitrogen variations were quantified, and their impacts were identified. • Five meteorological variables significantly correlated with Nitrogen variations. • The strength of the correlation coefficient (r) varied across the multiple time scales. • Changes in meteorological conditions affect the timing and magnitude of nitrogen variations in Taihu lake. [ABSTRACT FROM AUTHOR]

Water quality variation in semi-enclosed urban coastal areas with different pollutant sources is a substantial issue. Pollutant entrapment has a significant impact on the lives of the local people. Surface water quality modelling often requires large datasets covering bathymetry, fluid and pollutants boundary conditions, sources and sinks. This is particularly challenging in regions with complex features and poor data availability, such as coastal water bodies featuring a large number of widely distributed islands and estuaries. In this paper, we developed a model of surface water quality and hydrodynamics for Ha Long Bay, in the North of Vietnam and includes 1969 islands, for a one-year period using a water quality dataset obtained for this study. The model utilized extracted bathymetric and geometric data from Admiralty Charts and Admiralty Tide Tables. Water quality coupled with the TELEMAC Model (WAQTEL) Biomass Module was employed to predict pollutant transport in the domain using point and diffused sources while field studies were conducted to collect data for the setting up and calibration of the water quality model. Thirty scattered sampling points were selected, and the water quality parameters were measured during two campaigns. The predicted water level and velocity values matched the local observation data well with a small error (RMSE = 0.19 and 0.16). Both NO 3 −-N and PO 4 3--P were high near the shoreline and decrease gradually offshore. The maximum concentrations of NO 3 −-N and PO 4 3--P reached 0.476 mg/L and 0.048 mg/L at the end of 2021 with the RMSE = 0.13 and 0.011, respectively. The levels of NO 3 −-N and PO 4 3--P and their distributions showed that Ha Long Bay was eutrophic even during the COVID-19 lockdown period. [Display omitted] • Water quality modelling in a semi-enclosed regions including lots of islands. • Hydro-environmental modelling in a region with poor bathymetric and water quality data availability. • NO 3 --N and PO 4 3--P prediction in a coastal area using WAQTEL-TELEMAC coupling. • Water hydrodynamic modelling in a complex geometry region. [ABSTRACT FROM AUTHOR]

The accumulation of microbes especially in the air and in water bodies is causing the major disease outbreaks. Indoor environment remediation methods are necessary today to clean up these microbes. Among the remediation methods available, in situ generation of highly reactive and oxidizing radical species by advanced oxidation processes (AOPs) inactivate most of the microbes unselectively. Of these AOPs, photocatalytic microbial disinfection especially under indoor conditions is of great interest to maintain microbe-free indoor environment. For efficient microbes' inactivation under indoor conditions, the near IR and IR response of the photocatalysts must be improved. Though the photocatalytic disinfection of microbes using semiconductor-based photocatalysts has been extensively investigated, most of the photocatalysts that have been investigated are either weekly responsive or totally not irresponsive to IR photons due to inappropriate bandgap energies. Several strategies have been investigated to enhance the light harvesting properties of semiconductor based photocatalysts under indoor conditions and make them active to near IR and IR radiations. This review summarizes the recent progress in the field of materials for photocatalysts employed for microbial removal in indoor environments over the past decade as well as outlines key perspectives to enlighten future researches. The paper details the fundamentals of photocatalysis and basic properties of photocatalytic materials in the disinfection of common microbes under indoor conditions. The applications of photocatalytic materials in the disinfection of microbes in indoor environmental conditions are discussed and reviewed. Finally, the remaining challenges and future strategies/prospects in the design and synthesis of IR (and near IR) responsive photocatalysts are discussed. • Elimination of microbes by NIR/IR photons is reviewed in the present study. • The use of NIR/IR photons for the degradation of microbes under indoor conditions was exploited. • Up-conversion, defect engineering, SPR and sensitization can be employed for microbial disinfection with IR photons. • Charge separation is one of the major issues in IR driven microbe degradations. • Novel materials to harvest NIR/IR radiations are indispensible for microbial disinfection under indoor conditions. [ABSTRACT FROM AUTHOR]

Water clarity is a critical parameter of water, it is typically measured using the setter disc depth (SDD). The accurate estimation of SDD for optically varying waters using remote sensing remains challenging. In this study, a water classification algorithm based on the Landsat 5 TM/Landsat 8 OLI satellite was used to distinguish different water types, in which the waters were divided into two types by using the a d (443)/a p (443) ratio. Water type 1 refers to waters dominated by phytoplankton, while water type 2 refers to waters dominated by non-algal particles. For the different water types, a specific algorithm was developed based on 994 in situ water samples collected from Chinese inland lakes during 42 cruises. First, the R rs (443)/R rs (655) ratio was used for water type 1 SDD estimation, and the band combination of (R rs (443)/R rs (655) - R rs (443)/R rs (560)) was proposed for water type 2. The accuracy assessment based on an independent validation dataset proved that the proposed algorithm performed well, with an R2 of 0.85, mean absolute percentage error (MAPE) of 25.98%, and root mean square error (RMSE) of 0.23 m. To demonstrate the applicability of the algorithm, it was extensively evaluated using data collected from Lake Erie and Lake Huron, and the estimation accuracy remained satisfactory (R2 = 0.87, MAPE = 28.04%, RMSE = 0.76 m). Furthermore, compared with existing empirical and semi-analytical SDD estimation algorithms, the algorithm proposed in this paper showed the best performance, and could be applied to other satellite sensors with similar band settings. Finally, this algorithm was successfully applied to map SDD levels of 107 lakes and reservoirs located in the Middle-Lower Yangtze Plain (MLYP) from 1984 to 2020 at a 30 m spatial resolution, and it was found that 53.27% of the lakes and reservoirs in the MLYP generally show an upward trend in SDD. This research provides a new technological approach for water environment monitoring in regional and even global lakes, and offers a scientific reference for water environment management of lakes in the MLYP. • An optical classification method for estimating water clarity in inland lakes is proposed. • The proposed algorithm had better performance than the other empirical and semi-analytical algorithms. • The proposed algorithm has the ability of mapping inland waters clarity with large-scale. • The 36-years of water clarity levels in the Middle-Lower Yangtze Plain were mapped using Landsat images. [ABSTRACT FROM AUTHOR]

The application of road salts for winter de-icing of roadways in cold regions has been demonstrated to increase chloride (Cl) concentrations in nearby surface waters and have a negative impact on aquatic organisms and processes. In addition to toxicity to aquatic organisms, high concentrations of Cl in lakes can alter mixing processes, resulting in prolonged anoxic conditions and associated water quality degradation. Elevated concentrations of Cl in freshwater environments in cold regions is a well-documented phenomenon, but few studies have undertaken a long-term evaluation of the impact of urbanization on lakes. In this paper, nine lakes in the Halifax region of Nova Scotia, Canada, were monitored over 35 years to observe Cl concentrations prior to, during, and after urbanizing development. Cl concentrations were observed to increase in most study lakes over the monitoring period and all nine exhibited seasonal trending in response to winter de-icing activities. Six of the lakes achieved a steady-state Cl level after an initial increase in response to development activities, two are potentially still in transition, and one was unaffected by development activities. Watershed land use was found to be a good predictor of the springtime concentration of Cl and can help to inform decision-making surrounding development activities. When the percent of developed land was 25% or more, the Cl concentrations tended to exceed Canadian freshwater quality guidelines for the protection of aquatic life. • Winter road salt application leads to elevated chloride levels in lakes and ponds. • Water bodies were studied over a 35-year period spanning pre- and post-development. • In urbanizing watersheds, lake chloride levels increased by a factor of 8 or more. • Most lakes fluctuate between a spring peak and fall minimum within a narrow range. • Chloride levels exceed water quality guidelines when watershed area is 25% developed. [ABSTRACT FROM AUTHOR]

Abstract: This paper explores late eighteenth-century and nineteenth-century mappings of three strategic sites in the Eastern Mediterranean, each with a notable ancient history: the Straits of the Dardanelles, and the isthmuses of Suez and Mount Athos. Considering mapping as a culturally and historically situated cognitive practice, the paper focuses on the rhetorical use of Classical antiquity (the Persian Wars) in the geopolitical discourse of that period and in the legitimization of great hydraulic projects, like the Suez Canal. At the same time, it also seeks to re-evaluate Mediterranean straits and isthmuses in their geographical specificity, as physical and imaginative ‘gateways’ to the Orient, as ‘connecting points’ and boundaries between the Self and the Other. [Copyright &y& Elsevier]

There is a huge risk of contamination of water bodies due to the various oil exploration, transport, and industrial operational activities that are taking place across the world. Physical remediation techniques are considered extremely important for tackling the problems of marine oil spills. This paper provides a unique, specific review on the physical remediation of marine oil spills with special emphasis on types of available physical remediation techniques and their working principles. It also describes the chief latest improvements in the physical remediation techniques that have taken place with time. The paper discusses the various ways by which oil and its derivatives contaminate, and the subsequent effects these contaminants have on the marine ecosystem. The article discusses salient features that make physical remediation an effective marine oil spill counter-measure capable of recovering appreciable amounts of oil while causing minimal or no damage to the marine ecosystem and the workers carrying out the cleanup. Regarding the physical remediation methods, future research may focus on the development of hybrid booms, improved performance of skimmers for different oil types, and further applications involving novel materials like nanoparticles, zeolites for sorbents. [Display omitted] • A unique, specific review on physical remediation of marine oil spills. • Merits, demerits of the remediation techniques are analyzed. • Environmental, oceanic conditions at the oil spill site are big factors. • Recent advancements in physical remediation techniques have been discussed. • Future research may target improved performance using skimmers, novel sorbents. [ABSTRACT FROM AUTHOR]

This paper provides an in-depth review of evidence for the presence of twelve waterbodies spanning the Late Pliocene through Late Pleistocene in southern Israel and southern Jordan. A comprehensive description of these waterbodies is presented, combined with new field, paleontological and numerical age data, along with a discussion of their implications for paleohydrology and paleoclimate. The region is currently hyper-arid and there are no permanent rivers, wetlands or lakes in the area. Nevertheless, during the time-frame examined, continuous layers of limestones and mudstones were deposited in wetlands and shallow lakes. According to their location, the waterbodies were classified into either resulting from local tectonic depressions or in wide natural depressions at base levels. Following the types of sediments and fauna associated with these waterbodies, it is suggested that four wetter periods occurred: Late Pliocene/Early Pleistocene, Middle Pleistocene, Middle Late Pleistocene and terminal Late Pleistocene. This resulted in the deposition of limestone, chalk, travertine, calcrete, mudstone, marl, clay, silt and sandstone. For several waterbodies, vertical and lateral transitions between white limestone and fine clastic sediments rich in carbonate, indicate changes in depositional conditions from a shallow lake to a wetland, both associated with wetter hydrological settings compared to current climatic conditions. [ABSTRACT FROM AUTHOR]

Infection of antibiotic-resistant pathogens mostly occurs in rural areas. In this paper, the dissemination of antibiotic resistance genes (ARGs) through fecal sewage treatment facilities to the ecosystem in a typical rural area is investigated. Household three-chamber septic tanks (TCs), household biogas digesters (BDs), wastewater treatment plants (WWTPs), vegetable plots, water ponds, etc. Are taken into account. The relative abundance of ARGs in fecal sewage can be reduced by BDs and WWTPs by 80% and 60%, respectively. While TCs show no reduction ability for ARGs. Fast expectation-maximization microbial source tracking (FEAST) analysis revealed that TCs and BDs contribute a considerable percentage (15–22%) of ARGs to the surface water bodies (water ponds) in the rural area. Most ARGs tend to precipitate in the sediments of water bodies and stop moving downstream. Meanwhile, the immigration of microorganisms is more active than that of ARGs. The results provide scientific basic data for the management of fecal sewage and the controlling of ARGs in rural areas. [Display omitted] • ARGs in three types of fecal sewage treatment facilities were characterized. • Sources of ARGs in surface water bodies and soils is analyzed by FEAST. • Relative abundance of ARGs cannot reduced by TCs but BDs and WWTPs. • TCs and BDs contribute considerable percentage of ARGs to surface water bodies. • ARGs tend to precipitate and stabilized in the sediments. [ABSTRACT FROM AUTHOR]

In this review paper, the milestones and challenges that have been achieved and experienced by African Environmental Scientists regarding the assessment of water pollution caused by the presence of pharmaceutical compounds in water bodies are highlighted. The identification and quantification of pharmaceuticals in the African water bodies is important to the general public at large due to the lack of information. The consumption of pharmaceuticals to promote human health is usually followed by excretion of these drugs via urine or fecal matter due to their slight transformation in the human metabolism. Therefore, large amounts of pharmaceuticals are being discharged continuously from wastewater treatment plants into African rivers due to inefficiency of employed sewage treatment processes. Large portions of African communities do not even have proper sanitation systems which results in direct contamination of water resources with human waste that contains pharmaceutical constituents among other pollutants. Therefore, this article provides the overview of the recent studies published, mostly from 2012 to 2016, that have focused on the occurrence of different classes of pharmaceuticals in African aqueous systems. Also, the current analytical methods that are being used in Africa for pharmaceutical quantification in environmental waters are highlighted. African Scientists have started to investigate the materials and remediation processes for the elimination of pharmaceuticals from water. [ABSTRACT FROM AUTHOR]

Little information exists on the occurrence and the ultimate fate of pharmaceuticals in the water bodies in India despite being one of the world leaders in pharmaceutical production and consumption. This paper has reviewed 19 published reports of pharmaceutical occurrence in the aquatic environment in India [conventional activated sludge wastewater treatment plants (WTPs), hospital WTPs, rivers, and groundwater]. Carbamazepine (antipsychoactive), atenolol (antihypertensive), triclocarban and triclosan (antimicrobials), trimethoprim and sulfamethoxazole (antibacterials), ibuprofen and acetaminophen (analgesics), and caffeine (stimulant) are the most commonly detected at higher concentrations in Indian WTPs that treat predominantly the domestic sewage. The concentration of ciprofloxacin, sulfamethoxazole, amoxicillin, norfloxacin, and ofloxacin in Indian WTPs were up to 40 times higher than that in other countries in Europe, Australia, Asia, and North America. A very few studies in Indian rivers reported the presence of ciprofloxacin, enoxacin, ketoprofen, erythromycin, naproxen, ibuprofen, diclofenac and enrofloxacin. Similar compounds were reported in rivers in China, indicating a similar usage pattern in both of these developing countries. In a study reported from an open well in southern India, the groundwater showed the presence of cetirizine, ciprofloxacin, enoxacin, citalopram and terbinafine, which was close to a WTP receiving effluents from pharmaceutical production. [ABSTRACT FROM AUTHOR]

In recent years, issues relating to fat, oil and grease (FOG) in sewer systems have intensified. In the media, sewer blockages caused by FOG waste deposits, commonly referred to as ‘fatbergs’, are becoming a reminder of the problems that FOG waste can cause when left untreated. These FOG blockages lead to sanitary sewer overflows, property flooding and contamination of water bodies with sewage. Despite these financial and environmentally detrimental effects, a homogenous FOG waste management method has not been developed internationally. However, some successful enduring FOG management programmes have been established, such as in Dublin city and in Scandinavian countries. The aim of this paper is to carry out a review on existing FOG research and management approaches. FOG management involves comprehending: (1) FOG deposition factors in the sewer, (2) FOG prevention and awareness tactics undertaken internationally and (3) potential utilisation methods for FOG waste. This review will highlight that preventing FOG from entering the sewer is the most common approach, often through simple awareness campaigns. The diverted FOG is rarely valorised to bioenergy or biomaterials, despite its potential. Thus, all facets of the FOG waste lifecycle must be identified and managed. Advancements in processes and techniques must be assessed to best determine the future evolution of FOG waste management to assist in achieving a sustainable urban environment. [ABSTRACT FROM AUTHOR]

The construction of permeable pavement (PP) in sidewalks of urban areas is an alternative low impact development (LID) to control stormwater runoff volume and consequently decrease the discharge of pollutants in receiving water bodies. In this paper, some laboratory experiments were performed to evaluate the efficiency of a PP subjected to sediment loadings during its life span. Simple infiltration models were validated by the laboratory experiments to evaluate the trend and extend of PP infiltration capacity throughout the life of the pavement operation. In addition, performances of the PP in removing total suspended solids (TSS) and selective nutrient pollutants such as N O 3 − , N H 4 + and P O 4 − 3 from the surface runoff have been investigated. Experimental data showed that the PP was completely clogged after seven hydrological years. The model revealed that the ratio of horizontal to vertical hydraulic conductivity is 3.5 for this PP. Moreover, it was found that 20% reduction in hydraulic conductivity occurred after three hydrological years. The PP showed 100%, 23% and 59% efficiencies in sediment retention (TSS removal), ( P O 4 − 3 ) , and N − N H 4 + removal during the entire study, respectively. However, the removal efficiency of ( N − N O 3 − ) was −12% and we suspect the increase in effluent ( N − N O 3 − ) is due to the nitrification process in subsurface layers. This study demonstrated that when PPs are annually cleaned, it is expected that PPs can function hydraulically and be able to remove particulate pollutants during their life span by a proper maintenance. [ABSTRACT FROM AUTHOR]

Geospatial landscape connectivity modeling techniques are widely used in archaeological studies of past human movement patterns and landscape interactions. Recent advancements in the development of omnidirectional modeling approaches present new avenues for research design and require introduction into the field. In this paper, we present a novel adaptation of a point-based omnidirectional model design that we use to advance understandings of early colonial expansion (ca. 1600–1750 CE) into a social and ecological frontier landscape in the Northeastern United States, the Great Bay Estuary. We build case-specific resistance surfaces and use Circuitscape modeling to simulate the outward dispersal of settler colonists from the landscape's central water bodies while accounting for the influences of both water-based and overland travel, as well as the availability of specific natural resources. The outcome of the simulation performs well when tested statistically against the archaeological record and the value of multivariate model parameterization is highlighted both quantitatively and qualitatively. This case study offers a framework others could use to advance their own contextually-informed modeling of past human dispersal and landscape interactions. • Omnidirectional geospatial modeling methods are needed in archaeology. • We present a point-based circuitscape model of colonial dispersal in New England. • Input resistance surfaces consider navigable waters, overland travel, and wetlands. • Model performance is tested against the archaeological record with success. [ABSTRACT FROM AUTHOR]

With the development of remote sensing technology, significant progress has been made in the evaluation of the eco-environment. The remote sensing ecological index (RSEI) is one of the most widely used indices for the comprehensive evaluation of eco-environmental quality. This index is entirely based on remote sensing data and can monitor eco-environmental aspects quickly for a large area. However, the use of RSEI has some limitations. For example, its application is generally not uniform, the obtained results are stochastic in nature, and its calculation process cannot consider all ecological elements (especially the water element). In spite of the widespread application of the RSEI, improvements to its limitations are scarce. In this paper, we propose a new index named the remote sensing ecological index considering full elements (RSEIFE). The proposed RSEIFE is compared with commonly used evaluation models such as RSEI and RSEI LA (Remote Sensing Ecological Index with Local Adaptability) in several types of study areas to assess the stability and accuracy of our model. The results show that the calculation process of RSEIFE is more stable than those of RSEI and RSEI LA , and the results of RSEIFE are consistent with the real eco-environment surface and reveal more details about its features. Meanwhile, compared with RSEI and RSEI LA , the results of RSEIFE effectively reveal the ecological benefits of both water bodies themselves and their surrounding environments, which lead to more accurate and comprehensive basis for the implementation of environmental protection policies. [Display omitted] • We propose a new ecological index for land surface eco-environment simulation. • The instability and incompleteness of the RSEI, RSEI LA calculation was solved. • RSEIFE has stability and versatility in cities with different ecological contexts. • RSEIFE can monitor eco-environmental of cities with abundant water bodies. [ABSTRACT FROM AUTHOR]

The global expansion of cyanobacterial blooms poses a major risk to the safety of freshwater resources. As a result, many explorations have been performed at a regional scale to determine the underlying impact mechanism of cyanobacterial blooms for one or several waterbodies. However, two questions still need to be answered quantitatively at a global scale to assist the water management. One is to specify which factors were often selected as the driving forces of cyanobacterial blooms, and the other is to estimate their quantitative relationships. For that, this paper applied a systematic literature review for 41 peer-reviewed studies published before May 2021 and a statistical meta-analysis based on the Pearson's or Spearman's correlation coefficients from 27 studies. These results showed that the water quality, hydraulic conditions, meteorological conditions and nutrient levels were often considered the driving forces of cyanobacterial blooms in global freshwater systems. Among these, meteorological conditions and nutrient level had the highest probability of being chosen as the driving force. In addition, knowledge of the quantitative relationships between these driving forces and cyanobacterial blooms was newly synthesized based on the correlation coefficients. The results indicated that, at a global scale, meteorological conditions were negatively related to cyanobacterial blooms, and other driving forces, such as water quality, hydraulic conditions and nutrient levels, were positively related to cyanobacterial blooms. In addition, the measurement indicators of these driving forces had diverse forms. For example, the nutrient level can be measured by the concentration of different forms of nitrogen or phosphorus, which may lead to different results in correlation analysis. Thus, a subgroup meta-analysis was necessary for the subdivided driving forces and cyanobacterial blooms, which had a better accuracy. Overall, the synthesized knowledge can help guide advanced cyanobacteria-centered water management, especially when the necessary cyanobacterial data of targeting waterbodies are inaccessible. • Quantitative impacts of driving forces on blooms were synthesized globally. • Water quality, hydraulics, meteorology and nutrient were mainstream drivers. • Blooms were quantified by chlorophyll-a concentration, or richness of species. • Meteorological drivers were negatively related with cyanobacterial blooms. • Nutrients were the most considered drivers and were positively related with blooms. [ABSTRACT FROM AUTHOR]

There may be a chance of small-scale ephemeral liquid water formation on present-day Mars, even though the current climate does not support the existence of larger bodies of water. Through a process called deliquescence, hygroscopic salts can enter solution by absorbing water vapor directly from the atmosphere. Due to the absence of in-situ deliquescence experiments so far, the most reliable way to forecast deliquescence is through atmospheric modeling; however, the locations and times when salty liquid water could emerge are not yet well known. In this paper, we present our results of likely brine formation on Mars, its proposed locations and seasons, as well as the possible limiting factors. For our calculations we used the data of Laboratoire de Météorologie Dynamique Mars General Circulation Model version 5. The results show that from L s 3 5 ∘ - L s 16 0 ∘ , between 9 PM and 11 PM there is a good chance for calcium perchlorate deliquescence above 30 ∘ N, while in this zone the ideal regions are concentrated mostly to Acidalia Planitia and Utopia Planitia. We found that in the Southern Hemisphere, between L s 19 5 ∘ and L s 32 0 ∘ , there is a noticeable, but weaker, band in the vicinity of 60 ∘ S, and both Argyre Planitia and Hellas Planitia show some chance for brine formation. According to our results, the key limiting circumstance of deliquescence could be relative humidity in most cases, when the circumstances are nearly ideal (with the exception of one factor only). Our results suggest that during summer–early fall seasons, there could be deliquescence in both hemispheres in specific areas from the late evening until the early morning hours. There are only few studies detailing the geological and temporal distribution of brine formation through deliquescence; thus, this work could be used as a good guide for future landing site analysis or in choosing a specific location for further research. • We investigate seasonal and global chance for perchlorate deliquescence on Mars. • Good chance for deliquescence Ls 35 ∘ - Ls 160 ∘ above 30 ∘ N. • Ideal regions are concentrated mostly to Acidalia Planitia and Utopia Planitia. • Some deliquescence chance near 60 ∘ S from Ls 195 ∘ to Ls 320 ∘. • When conditions are almost ideal, relative humidity seems to be the limiting value. [ABSTRACT FROM AUTHOR]

This paper discusses developing a novel spectral index for desert sand dunes detection using four bands from Sentinel-2 data. This index, called Normalized Difference Enhanced Sand Index (NDESI), uses the blue band (492 nm), the red (664 nm) or the Vegetation Red Edge (VRE) band (782 nm), and two of the Shortwave Infrared (SWIR) bands (1613 and 2202 nm) to generate a grayscale image, where DN values are within −2 to 2. The lowest and highest values represent water bodies and sand dunes, respectively. A threshold calculation technique was used to generate a unique threshold for each image. This index application on several images covering the northern region of Figuig city seems to perfectly highlight sand dunes all over the image, with an overall accuracy of 97.9% and a kappa coefficient of 83.4%. This index is adapted for Landsat 8 data and can track sand dunes change over time. • New spectral index for desert sand dunes detection and monitoring. • Made for Sentinel-2, Landsat-8 and any sensor that have the required bands. • Can discriminate sandy surfaces from soils and alluvium. • Have good accuracy for sand dunes detection. [ABSTRACT FROM AUTHOR]

This paper introduces a new framework to evaluate the resilience of lakes under climatic and anthropogenic droughts. The proposed hierarchical structure of criteria for assessing lake's resilience has four levels. The first level includes several indices such as long-term resilience, reliability, and implementation cost. In the second to fourth levels, four main resilience-based criteria (i.e. robustness, resourcefulness, redundancy, and rapidity) and some qualitative and quantitative sub-criteria are defined considering the factors affecting the ecological condition of lakes. To quantify the time series of the sub-criteria, a coupled SWAT-MODSIM-based simulation model has been applied. Also, the values of criteria and sub-criteria have been aggregated using the Evidential Reasoning (ER) approach. After estimating the annual resilience time series, three resilience indices, namely the recovery time (Tr), loss of resilience (LOR), and final resilience (Res f), have been calculated. The normalized values of these indices and reliability criteria have been aggregated to evaluate the overall performance of lake restoration scenarios. To show the applicability of the proposed methodology, the Zarrinehrud river basin and Lake Urmia have been selected as the case study. As one of the largest hypersaline lakes globally, Lake Urmia suffers from drastic changes in its water body and a high level of salinization. Also, the Zarrinehrud river basin, located in the southeastern of Urmia Lake, is the most significant sub-basin of the lake and is responsible for supplying 41% of the total annual inflow of the lake. The restoration scenarios of Lake Urmia have been assessed from 2019 to 2049. Eventually, the most effective scenario, which has an average overall performance of 0.72, the implementation cost of 17.1 million dollars, and the uncertainty band of 0.05, has been selected. • A new methodology is proposed for evaluating resilience of lakes under drought. • Some new criteria are proposed for assessing the lake's ecological condition. • The evidential reasoning approach is utilized for combining resilience sub-criteria. • Three new resilience indices have been proposed for evaluating management scenarios. • The methodology has been applied to Lake Urmia and Zarrinehrud river basin in Iran. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines disposal of metals and the origin, characteristics, and distribution of sedimentary organic matter (SOM) in a Mediterranean karstic estuary in the north-eastern Adriatic. This environment offers a real-time, small model system for studies of geochemical processes in microtidal Mediterranean estuaries that are infilling with sediments and classified as river-dominated disequilibrium estuaries. The results have shown that the longitudinal distribution of heavy metals in sediments follows the sedimentation dynamics and deposition pattern of river-borne, clay mineral particles. The highest concentration of metals was found in the restricted upper part of the estuary, characterized by rapid deposition of clay particles and terrestrial sedimentary organic matter, and decreases toward the open sea. The vertical distribution of metals in sediment cores depends on the prevailing pH and Eh conditions. Significant increases of the concentrations of metals in the uppermost strata are the result of recent anthropogenic inputs. The share of the terrestrial component in SOM, estimated by N/Corg atomic ratios and δ13C values, decreases with distance from the river mouth. The small vertical variation in δ13C values of SOM indicates that a fast sedimentation rate overrides the diagenetically determined decomposition. The results obtained indicate that river-borne inorganic particles, natural terrigenous organic material, and anthropogenic metal loads are trapped in sediments of the estuarine system. Under the prevailing conditions, there is negligible transport towards the open sea. [Copyright &y& Elsevier]

Abstract: For at least 200 years, Gomoti River people and their neighbours lived interactively with the Okavango flood pulse system, travelling widely in dugout canoes, practicing flood recession agriculture, fishing, hunting, and collecting wild foods. Today they are wetlanders without wetlands. A major outflow channel of the eastern Okavango Delta in the 1930s, the Gomoti River rarely flows these days. This paper explores the Gomoti''s demise, through the lenses first of science and second of Gomoti basin residents. Models developed over the past 20 years attribute the Gomoti''s drying to a complex set of bio-hydrologic processes and feedback loops that begin with sedimentation and conclude with channel switching, peat fires, and purging of toxic salts. Such models essentially omit the long history of human habitation and ecological interaction with the delta. Local people, on the other hand, tell of deliberate and systematic management of channels and floodplains, and they argue this management kept the river healthy and flowing. The picture is confounded by colonial era interventions and by Botswana government policies partitioning the Gomoti and restricting access to its headwaters. We conclude with a model combining meso-scale scientific explanation with micro-scale indigenous constructions as a context for new thinking about Okavango Delta resource management. [Copyright &y& Elsevier]

Abstract: This paper explores the relationship between tourism, abandoned landscapes, and the construction of ‘typical’ identity in rural Vermont. Between the 1880s and the 1930s, Vermonters were both celebrated in the popular press as archetypal Americans and depicted as a people in decline. With the state''s reputation plagued by rural out-migration, many reformers, state officials, and rural residents tried to shore up and reproduce the identity of the so-called typical Vermonter through the sale of abandoned farms as summer homes. The promise of summer tourism as a means for reproducing typicality in rural Vermont, however, was complicated by the contingency of the category typical and by persistent fears that a new leisure-based economy and allegedly ‘wrong kinds’ of visitors would undermine the integrity of the state''s traditional rural identity. As a result, visitors and residents negotiated an ideal of rural typicality according to changing tourist circumstances—a process revealed in this essay largely through published commentaries and promotional works. What this story traces, then, is landscape''s role in the production of ‘ideal’, tourist-based notions of rural identity in American culture. [Copyright &y& Elsevier]

Abstract: The residence time measures the time spent by a water parcel or a pollutant in a given water body and is therefore a widely used concept in environmental studies. While many previous studies rely on severe hypotheses (assuming stationarity of the flow and/or neglecting diffusion) to evaluate the residence time, the paper introduces a general method for computing the residence time and/or the mean residence time without such simplifying hypotheses. The method is based on the resolution of an adjoint advection–diffusion problem and is therefore primarily meant to be used with numerical models. The method and its implications are first introduced using a simplified one-dimensional analytical model. The approach is then applied to the diagnostic of the three-dimensional circulation on the Northwest European Continental Shelf. [Copyright &y& Elsevier]

As the abundance of microplastics and nanoplastics (MPs/NPs) increases in the environment, their presence in agricultural soil has become of interest. MPs/NPs can affect soil physical and chemical properties and be absorbed by plants and soil animals, causing physical and chemical damage. Soil MPs exceeding a certain concentration cause significant harm. Therefore, the extraction and identification of MPs in soil are vital for determining soil pollution. However, soils contain many other particles of similar size to MPs/NPs, making it more difficult to distinguish them than in water bodies. No standardized extraction and identification method is available to quantify MPs/NPs in soil. Various methods have been described in the literature, but they involve many different procedures for sampling, purification, digestion, and identification. This paper reviews extraction and identification methods for MPs/NPs in soil, sediment, and water and summarizes agricultural soil sampling and preservation, MPs/NPs separation, organic matter removal, and MPs/NPs identification. We also compare the advantages and disadvantages of existing methods and propose future research topics. [Display omitted] • Made recommendations for extraction and identification of NPs. • Compared the advantages and disadvantages of various methods. • Provided the basic operation process for extraction and identification of MPs/NPs. [ABSTRACT FROM AUTHOR]

Automatic water body extraction from satellite images of various scenes is a classical and challenging task in remote sensing and image interpretation. Convolutional neural network (CNN) has become prominent option for performing image segmentation task in remote sensing applications. However, CNN-based networks have non-trivial issues for segmenting such as: (1) blurring boundary pixels; (2) large number of trainable parameters; and (3) huge number of training samples. In this paper, we propose an end-to-end multi-feature based CNN architecture, called as W-Net, to perform water body segmentation. W-Net consists of contracting/expanding networks and inception layers. W-Net takes advantage of contracting network to capture context information while localization is achieved with expanding network. With these networks, W-Net is able to train on less number of images and extract water pixels accurately. Use of inception layers reduces computational burden within the network by decreasing total number of trainable parameters. W-Net incorporated two refinement modules to enhance predicted results which mitigate blurring effect and to inspect continuity of boundary pixels. Dataset consisting 2671 images with manually annotated ground truths are built to validate performance and effectiveness of our proposed method. In addition, we evaluated our method on crack detection dataset where W-Net achieved competitive performance with Deepcrack. W-Net accomplished excellent performance on the water body dataset (I ∕ U = 0. 9434 and F − s c o r e = 0. 9509). • Water body segmentation is crucial for many applications. • W-Net consists of inception blocks at both encoder and decoder paths. • Use of asymmetric convolution reduces trainable parameters within the network. • Refinement modules enhances predicted image and identifies boundary pixels accurately. [ABSTRACT FROM AUTHOR]

A new method for algal community restructuring is proposed, where harmful algae growth is inhibited through the addition of remedial nano-agent, while probiotic algae growth is promoted or only affected indistinctively. In this paper, the inhibiting effects of five different nanomaterials on Microcystis aeruginosa (M. aeruginosa) and Cyclotella sp. were studied, and the optimal nanomaterial was served as algae-inhibition ingredient of the remedial agent. The effects of the remedial agent on algal growth and their physiological characteristics were investigated, and the restructuring of algal community in actual water samples was explored. The results indicated that the inhibition ratio of 10 mg/L nm-Cu 2 O/SiO 2 on M. aeruginosa and Cyclotella sp. could reach 293.1% and 82.8% respectively, acting as the best candidate for algae-inhibiting ingredient. After adding the remedial nano-agent made with nm-Cu 2 O/SiO 2 , the content of chlorophyll a , protein, and polysaccharides of M. aeruginosa decreased sharply, while the physiological characteristics of Cyclotella sp. were not significantly affected. Besides, the total biomass and proportion of cyanobacteria dropped (P < 0.05), but the Bacillariophyta biomass increased significantly (P < 0.05). The uniformity index, Shannon-Wiener index, and richness index all increased significantly (P < 0.05). Meanwhile, the quality of actual water samples has been improved evidently (P < 0.001). Therefore, the prepared remedial nano-agent in this study can control the harmful algae bloom to a certain extent by restructuring the algal community in eutrophic water bodies. Image 1 • Algal community restructuring using nanomaterials is proposed to curb algae blooms. • The restructuring relies on promoting diatom growth and curbing cyanobacteria growth. • Remedial nano-agent improved water quality in real water samples. • The restructuring of algal community was realized in real water samples. [ABSTRACT FROM AUTHOR]

Stable isotope technology has been widely used to trace sources and evolution of water bodies, relationships between different water bodies and pollution sources. Based on δ 18O and δD data from the Yarlung Tsangpo River in 2017, this paper analyzes the composition characteristics of δ 18O and δ D in the river water during the low-flow, high-flow and normal-flow seasons of the entire Yarlung Tsangpo River and further reveals the spatial evolution and influencing factors. The results show that the values of δ 18O, δD and d-excess were different in time and space. The δ 18O, δD and d-excess values of the Yarlung Tsangpo River in the low-flow season were significantly higher than in the high-flow season. This was mainly due to weak evaporation enrichment and precipitation supply effects on the river water during the wet season. From the perspective of season change, the d-excess in the low-season is significantly higher than in the high-flow season and the normal-flow season; from the perspective of spatial change, the d-excess shows the same spatial variation trend as the δ 18O, which first decreases and then increases. Based on the investigation of δ18O and δD in the main and Branch rivers of the Yarlung Tsangpo River Basin, it was found that the upper reaches of the basin were mainly supplied by snowmelt, the lower reaches were mainly supplied by rainfall. • Altitude effect: The composition of δD and δ 18O isotopes was gradually enriched with light isotopes as the altitude increased; thus, δD and δ 18O gradually decreased. The height effect was related to the distribution of temperature and terrain: when the altitude increased, the terrain became higher, the temperature decreased, the isotope fractionation coefficient increased, and the values of δD and δ 18O in atmospheric precipitation were lower, and it was rich in light isotopes. Obviously, as the altitude increased, δD and δ 18O became lower and show a positive correlation. The δ 18O value of the Yarlung Tsangpo River demonstrated a significant height effect. • By analyzing the characteristics of δD and δ 18O composition in the water of the Yarlung Tsangpo River during the low and high water periods, it was found that δD, δ 18O and d-excess values in the water of the Yarlung Tsangpo River were significantly different in time and space, and δD, δ 18O and d-excess values in the low-flow season were significantly higher than those in the high-flow season, which was mainly due to the weak evaporation enrichment effect and precipitation supply in the high water period. The δ 18O value increased gradually from the upstream to the downstream, which was related to the inflow of tributaries and lake water from different reaches of the Yarlung Tsangpo River. • There is a positive proportional relationship between δ 18O content and rainfall in the Yarlung Tsangpo River Basin. Due to the different water vapor sources and water vapor cycle patterns between the north and the south, the uplift of the plateau and the Himalayas caused the decrease of δ 18O in the river water of the plateau. The measured data show that the δ 18O value in the water body of the Yarlung Tsangpo River gradually increases from upstream to downstream, which may also be related to the cross contribution of tributaries and lakes along the river. [ABSTRACT FROM AUTHOR]

Worldwide water quality is degrading and most of the water bodies are now being contaminated by heavy load of pollutants from various industries. Aquatic ecosystems are also disrupted affecting various flora and fauna adversely. Water bodies dominated with aquatic plants have high yielding capacity. These plants are capable of high nutrient accumulation and creating favorable condition in rhizosphere for microbial organic degradation, which can be applied in the restoration process of polluted lakes, natural streams and wetlands, etc. Ecological Floating Bed (EFB) is designed by using aquatic plants, floating like mat on the surface of water. The plant roots hang beneath the floating mat and provide a large surface area for biofilm growth. This paper reviewed the EFB concept, structure, mechanisms and functions. Screening of suitable macrophyte species, involvement of biofilm in organic removal process and necessity of growth media have been discussed briefly. Apart from this, effect of depth, buoyancy, vegetation coverage ratio are also represented. Detail mechanisms of oxygen transfer from top to bottom of water biomass have been well analyzed. Various pollutants present in wastewater like organics, solids, nitrogen, phosphorous, heavy metals etc. and their removal mechanism have also mentioned. Again biomass needs to be harvested in regular interval, else the absorbed nutrients may re-enter to the water body. Overall, EFB is an efficient and effective wastewater treatment technology and further research is necessary for its better utilization. Finally, based on reviews, recommendations have been made for future research. Image 1 • Factors considered in Design of Ecological Floating Bed (EFB). • Various mechanism of oxygen transfer in aquatic plants. • Process of heavy metal removal from wastewater by EFB. • Biomass harvesting in floating bed and its maintenance. [ABSTRACT FROM AUTHOR]