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The existence of potential pathogens may lead to severe water pollution, disease transmission, and the risk of infectious diseases, posing threats to the stability of aquatic ecosystems and human health. In-depth research on the dynamic of potential pathogenic communities is of significant importance, it can provide crucial support for assessing the health status of aquatic ecosystems, maintaining ecological balance, promoting sustainable economic development, and safeguarding human health. Nevertheless, the current understanding of the distribution and geographic patterns of potential pathogens in coastal ecosystems remains rather limited. Here, we investigated the diversity, assembly, and co-occurrence network of potential pathogenic communities in two anthropogenic coastal regions, i.e., the eight mouths (EPR) and nearshore region (NSE), of the Pearl River Estuary (PRE) and a total of 11 potential pathogenic types were detected. The composition and diversity of potential pathogenic communities exhibited noteworthy distinctions between the EPR and NSE, with 6 shared potential pathogenic families. Additionally, in the NSE, a significant pattern of geographic decay was observed, whereas in the EPR, the pattern of geographic decay was not significant. Based on the Stegen null model, it was noted that undominant processes (53.36%/69.24%) and heterogeneous selection (27.35%/25.19%) dominated the assembly of potential pathogenic communities in EPR and NSE. Co-occurrence network analysis showed higher number of nodes, a lower average path length and graph diameter, as well as higher level of negative co-occurrences and modularity in EPR than those in NSE, indicating more complex and stable correlations between potential pathogens in EPR. These findings lay the groundwork for the effective management of potential pathogens, offering essential information for ecosystem conservation and public health considerations in the anthropogenic coastal regions.

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Instability is a key challenge for current pH sensors in practical applications, especially in aquatic environments with high biomass and redox substances. Herein, we present a novel approach that uses a highly stable IrOx sensing layer enveloped in a composite film of SPEEK doped with a silicon-stabilized ionic liquid (SP-IrOx). This design mitigates drift due to sensitive layer variations and minimizes interference from complex external conditions. After exhibiting robustness under moderately reducing conditions caused by S2-, I-, and ascorbic acid, the SP-IrOx sensor's efficacy was validated through real-time pH measurements in demanding aquatic settings. These included laboratory algal culture medium, sediment substrates, and mussel aquaculture areas. The sensor sustained accuracy and stability over extended periods of 6-8 days when compared to calibrated commercial electrodes. The deviations from reference samples were minimal, with a variance of no more than 0.03 pH units in mussel aquaculture areas (n = 17) and 0.07 pH units in an algal culture medium (n = 37). As a potentiometric, this solid-state electrode features a compact structure and low energy consumption, making it an economical and low-maintenance solution for precise pH monitoring in diverse challenging environments with high biomass and turbidity.

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This study aimed to predict the dynamics of per- and polyfluoroalkyl substance (PFAS) contamination and ecological vulnerability within coastal regions of Africa utilizing time-averaged remote-sensed data patterns from 2020 to 2023. The analysis identified PFAS contamination hotspots along the coast of Africa, particularly in western Africa around Nigeria and in areas spanning Equatorial Guinea and Guinea-Bissau, with risk influenced by eastward wind patterns, overland runoff, and elevated aerosol optical depth (AOD) values. Regional trends indicated that variations in solar energy absorption and surface air temperature could influence PFAS dynamics in North Africa, South Africa, East Africa, and West Africa. In North Africa, intermediate overland runoff and lower sea-surface temperatures were observed. In South Africa, there were intermediate runoff levels and warmer sea-surface temperatures. East Africa experienced intermediate runoff as well. In West Africa, there was increased susceptibility to high overland runoff and aerosol-related PFAS contamination. From the weighted vulnerability index, significant disparities in environmental conditions across African coastal regions revealed that North Africa had relatively lower vulnerability, while West Africa had the highest susceptibility to per- and polyfluoroalkyl substance (PFAS) contamination. This study emphasizes the necessity for region-specific vulnerability index models and targeted mitigation strategies to address diverse ecological and health risks from PFAS contamination along the African coast. Regional and international collaboration, spearheaded by organizations such as the AU and ECOWAS, is essential, with tailored policies aligned with the SDGs, Agenda 2063, and NEPAD crucial for effective environmental management, urging policymakers to prioritize cooperation and resource sharing for comprehensive sustainability goals.

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The adoption of environmentally-friendly habits has become more crucial in the present period as a means to mitigate the rate of environmental degradation and its detrimental consequences. The augmentation of sports, exercise and physical activities has been associated with favourable health outcomes, in addition to the ability to mitigate carbon emissions resulting from vehicular transportation. Consequently, the objective of this study is to examine the influence of sports, exercise, and physical activities, along with public health expenditure, on the environmental performance of China's coastal regions throughout the period spanning from 2010 to 2019. The proposed study employs the Feasible Generalized Least Squares (F.G.L.S) and the Generalized Method of Moments (G.M.M) methodologies. Results show that participation in sports and other forms of physical activity significantly improves environmental performance in China's coastal areas. Likewise, a robust negative correlation exists between air pollution and healthcare expenses, hence favouring enhanced environmental outcomes. Nevertheless, it is important to acknowledge that economic expansion has a direct correlation with increased emissions, hence harming environmental performance. There exists compelling evidence indicating a significant impact on environmental quality resulting from the combined influence of heightened health expenditures and increased engagement in sports. This is demonstrated by the presence of an interaction term between health expenses and sports activities. The findings of this study suggest that there is a requirement to re-evaluate healthcare spending initiatives and sporting activities in order to effectively pursue carbon neutrality goals and improve environmental sustainability.

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Microplastic identification and distribution throughout oceans has become a great concern due to its substantial uprising and its consequent interactions with marine biota. Microplastics can be absorbed and adsorbed by several marine species owing to their very small size. Among these organisms are bivalves, including ones used as food for humans. In this context, this research aims to understand the absorption scale of microplastics by Tivela mactroides according to their size and consequently life stage. Thus, T. mactroides mussels were collected at Camburi Beach (Brazil) and grouped into 30 different size classes from 06 to 35 mm. Later, 20 specimens from each size class (N = 600) had the soft tissues removed and a pool was performed through digestion with 10 % KOH solution. Results showed the presence of microplastics in all size classes of T. mactroides, evidencing that organisms from 06 mm can already be contaminated by microplastics and a tendency of the number of microplastics particles to increase as shell size increases. Furthermore, the amount of blue filament-type MPs was significantly higher than the other types and colors. Additionally, analyzes performed by Raman spectroscopy showed that the blue filaments have a PET composition. Finally, larger individuals presented larger quantities of MPs, as well as larger filaments. This might suggest that there are differences between the assimilation of the size of MPs in the different size classes, i.e. that size makes a difference.

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In consideration of the distinct behavior of machine learning (ML) algorithms, six well-defined ML used were carried out in this study for predicting sea level on a day-to-day basis. Data compiled from 1985 to 2018 was utilized for training and testing the developed models. An assessment of the multiple statistics-driven regression algorithms resulted such that each tested location was associated with a particular preferred model. The following were the developed best models for their respective study areas: In Peninsular Malaysia, the interactions linear regression model was the best at Pulau Langkawi (RMSE = 19.066), the Matern 5/2 gaussian process regression model at Geting (RMSE = 49.891), and the trilayered artificial neural network at Pulau Pinang (RMSE = 20.026), while the linear regression model was the best at Sandakan in Sabah, East Malaysia (RMSE = 14.054). Other metrics, such as MAE and R-square, were also at their best values, each providing its best values, further substantiating the RMSE respectively, at each of the study areas. These empirical statistics (or metrics) also revealed that despite employing sea level as the sole parameter, results obtained were exceptional better when utilizing a 7-day lag, regardless of the model used. Notably, lag variables with less than a 7-day lag could degrade the model's accuracy in representing ground reality. The study emphasizes the importance of thorough training and testing of ML to aid decision-makers in developing mitigation actions for the climate change phenomena of sea level rise through reliable ML.

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This study was carried out to evaluate and analyze the fluctuations in groundwater for certain trace metals (Fe, Mn, Cu, Zn, Al, Cd, Cr, Pb, As, and Se) in Taizhou City over three years (2020-2022), evaluate the potential human health risks due to the consumption of groundwater. To quantify the spatiotemporal changes in groundwater trace metals, the heavy metal pollution index (HPI) and heavy metal evaluation index (HEI) were utilized. Furthermore, multivariate statistical methods were utilized to distinguish the sources of trace elements. Deterministic health risk assessment and Monte Carlo health risk simulation methods were employed to evaluate human health risks associated with exposure to trace metals. The results indicate that areas with higher pollution are in the south-central region, with low HPI increasing from 50% to 75% and low HEI from 68.75% to 81.25%, reflecting improved water quality. Correlation matrix analysis and principal component analysis (PCA) pinpointed anthropogenic sources as major trace metal contributors. Cr and As concentrations were associated with farming activities, Cd and Pb concentrations showed links to local industries such as e-waste recycling and shipbuilding. Furthermore, Cu levels in groundwater was influenced by the combined effects of industry, agriculture, and urban sewage discharge. Based on the hazard quotient (HQ) and hazard index (HI) calculations, the majority of groundwater samples did not exceed the reference values, indicating acceptable noncarcinogenic risks for both adults and children. However, the analysis of carcinogenic risk (CR) and uncertainty revealed an overall decreasing trend in carcinogenic risk, with Cr and Cd possessing the highest potential for causing carcinogenic risks. The sensitivities were 46.3%, 53.3%, and 70.3% for Cr, and 18.8%, 27.6%, and 9.3% for Cd.

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The degradation of groundwater (GW) quality due to seawater intrusion (SWI) is a major water security issue in water-scarce regions. This study aims to delineate the impact of SWI on the GW quality of a multilayered aquifer system in the eastern coastal region of Saudi Arabia. The physical and chemical properties of the GW were determined via field investigations and laboratory analyses. Irrigation indices (electrical conductivity (EC), potential salinity (PS), sodium adsorption ratio (SAR), Na%, Kelly's ratio (KR), magnesium adsorption ratio (MAR), and permeability index (PI)) and a SWI index (fsea) were obtained to assess the suitability of GW for irrigation. K-mean clustering, correlation analysis, and principal component analysis (PCA) were used to determine the relationship between irrigation hazard indices and the degree of SWI. The tested GW samples were grouped into four clusters (C1, C2, C3, and C4), with average SWI degrees of 15%, 8%, 5%, and 2%, respectively. The results showed that the tested GW was unsuitable for irrigation due to salinity hazards. However, a noticeable increase in sodium and magnesium hazards was also observed. Moreover, increasing the degree of SWI (fsea) was associated with increasing salinity, sodium, and magnesium, with higher values observed in the GW samples in cluster C1, followed by clusters C2, C3, and C4. The correlation analysis and PCA results illustrated that the irrigation indices, including EC, PS, SAR, and MAR, were grouped with the SWI index (fsea), indicating the possibility of using them as primary irrigation indices to reflect the impact of SWI on GW quality in coastal regions. The results of this study will help guide decision-makers toward proper management practices for SWI mitigation and enhancing GW quality for irrigation.

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Plastic debris has been reported in the marine environment since the '70s. These plastic materials are introduced into the marine environment in several sizes, one of them microplastics (MP), and they have drawn great interest and concern in the past decades. Consumption of MP can cause weight loss, feeding rate decrease, reproductive activity decrease, and several other negative effects. Ingestion of MPs has already been reported for some species of polychaetes but the use of these annelids in MP studies is still poorly reported. Costa et al. (2021) was the first study to investigate the capability of the reef-building polychaete Phragmatopoma caudata to incorporate microplastic in its colony's structures. This makes the colonies a reservoir of MP and thus they reflect the environment's quality regarding MP presence. Consequently, this specie becomes an important asset to MP pollution investigation in coastal areas. Therefore, this work aims to investigate the abundance of MPs on the coastline of Espírito Santo using P. caudata as an indicator of MP presence. For this, we collected samples of P. caudata colonies in 12 sampling sites along the Espírito Santo coast (three replicates at each site). These colony samples were processed to extract the MPs particles from the colony surface, its inner structure, and tissues from the individuals. These MPs were counted using a stereomicroscope and sorted according to their color and type (filament, fragment, and other). Statistical analysis was performed using GraphPad Prism 9.3.0. Significant values followed p < 0.05. We found MP particles in all 12 sampled beaches, configuring a pollution rate of 100 %. The number of filaments was notably greater than the number of fragments and others. The most impacted beaches were found inside the metropolitan region of the state. Finally, P. caudata is an efficient and trustable indicator of microplastic in coastal areas.

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Marine microplastic pollution is a major environmental challenge that threatens marine ecosystems and human health. Several models have been used to calculate and predict the theoretical amount of plastic waste discharged into the sea by coastal countries. Unlike earlier theoretical models of source discharge, we used the method of data normalisation to focus on the actual distribution of microplastics and their potential ecological risk in offshore surface waters. Our findings indicate that the average normalised abundance of microplastics in near-shore region of Bohai Sea was greater than the average normalised abundance of microplastics in the seas near the Yangtze River Delta urban agglomeration and the Pearl River Delta urban agglomeration. Moreover, the average amount of plastic waste discharged from terrestrial sources to the ocean per kilometre exhibited the following order: Bohai Rim urban agglomeration (150.90) (tonnes km-1) < the Pearl River Delta urban agglomeration (274.30) (tonnes km-1) < Yangtze River Delta urban agglomeration (577.44) (tonnes km-1). Further, the average microplastics abundance in offshore areas of different countries and the amount of plastic discharged per kilometre of the coastline were significantly negatively correlated, implying that microplastics were not necessarily abundant in coastal areas where large amounts of plastic are discharged into the sea. Hydrodynamic conditions had the greatest influence on the distribution of microplastics in offshore surface waters. The transport of nutrient salts from terrestrial areas to offshore waters was also influenced by hydrodynamics, with enrichment patterns in offshore areas exhibiting similar to those of microplastics. Therefore, when the offshore microplastic accumulation area overlapped with the nutrient salt enrichment zone, the health risk associated with the consumption of edible fish from offshore communities increased. In view of these findings, coastal countries must implement policies to reduce marine plastic waste emissions and develop management strategies based on their local pollution levels.

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Understanding the spatial distribution pattern change and driving factors behind ecosystem health is essential to ecosystem management and restoration. However, in the research of regional ecosystem health, there is little research on ecosystem health in coastal regions, and there is little exploration of its temporal and spatial pattern change and its driving factors. In this study, we use the Vigor-Organization-Resilience-Services (VORS) model and marine ecosystem health index to diagnose the ecosystem health of the whole coastal area of China over the last 20 years, and find the main contributing factors affecting ecosystem health with the help of geographic detectors and geographic weighted regression analysis. Our results show that: (1) the ecosystem health level in the south of the coastal region is higher than that in the north, mainly with 30° north latitude as the main dividing line. (2) The regions with high change rate are mainly concentrated in Bohai Bay, the Yangtze River Estuary, Hangzhou Bay and the Pearl River Estuary, and the change is mainly negative. (3) Both natural and human factors have an impact on ecosystem health, and the influencing factors are different on different scales. The interaction between different factors is greater than the impact of a single factor on ecosystem health. The study puts forward a new evaluation framework for the study of ecosystem health in coastal areas, which can be applied to other coastal areas with similar conditions, and can help the sustainable and healthy development of coastal areas.

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Submarine groundwater discharge (SGD) has been recognized as an integral pathway of hydrological cycle. The role of SGD as a mechanism for material transport from terrestrial to marine ecosystems has also been investigated, considering the large hydrological flux and a massive load of solutes is found to be carried as SGD to the coastal oceans. However, there are challenges in recognizing the process and delineating specific areas which are susceptible to SGD. Considering the unique geochemical signature of groundwaters found in varied lithology, this paper investigates the possibility of using geochemical ratios and their variability in coastal areas as a tracer for the identification of SGD. The Br-/Cl- ratio, prevalently used for identification of seawater-groundwater mixing is investigated. The study raises questions over the viability of Br-/Cl- as a tracer as Br- rich groundwater in the SGD prevalent area may be a cause of elevated Br-/Cl- ratio in the coastal oceans. Furthermore, the peculiar observation of Fe+2 enrichment in coastal seawater also indicated the influence of differential weathering on the subterranean estuarine (STE) sediments releasing Fe+2 as the groundwater in the area is not enriched in groundwater. This observation is very important in the context of rising sea levels as a larger STE due to rising sea levels can cause higher mobilization of Fe+2 in coastal oceans causing a direct influence on the coastal ecosystem.

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Using an improved multimedia fate model, this study simulated the spatial distributions, partitioning behaviors, and mass exchanges of PAH16 (16 species with priority by the USEPA) in multiple environmental compartments in the coastal regions of the Bohai and Yellow Seas, Northern China. The model predictions generally matched well with the measured results, as the deviations of most points were within one order of magnitude in the air, freshwater, and 3 soil compartments. The estimated concentrations of ΣPAH16 in the northern part were higher than those in the southern part, which was consistent with the emissions of each part. Approximately 97.6% of the ΣPAH16 mass was distributed in soils; therefore, soils served as the dominant sink of PAH16. The estimated net flux of ΣPAH16 from air to soil ranged from 0.4 to 10.7 mg/m2/year (an average of 3.2 mg/m2/year), and the estimated flux of deposition from air to soil fell in the range of 0.4-10.8 mg/m2/year (an average of 3.2 mg/m2/year), which served as the dominant process at the air-soil interface. The estimated net flux of ΣPAH16 from air to freshwater ranged from -15.3 to 9.4 mg/m2/year (an average of -0.3 mg/m2/year), and the reversed volatilization flux from freshwater to air ranged from 0.01 to 21.1 mg/m2/year (an average of 3.7 mg/m2/year). This situation indicated notable spatial variations and volatilization as the main process affecting the direction of net flux at the air-freshwater interface. Deterministic risk assessment and probabilistic risk assessment were conducted. The overall health risks of the studied regions were acceptable, while the excess lifetime cancer risk (ELCR) by air inhalation was greater than that by soil ingestion. CAPSULE: Multimedia fate model-predicted distributions and compositions of PAH16 in different compartments, compartmental exchange fluxes and directions, and deterministic and probabilistic ELCR via different exposure pathways were assessed.

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Face masks are playing an essential role in preventing the spread of COVID-19. Face masks such as N95, and surgical masks, contain a considerable portion of non-recyclable plastic material. Marine plastic pollution is likely to increase due to the rapid use and improper dispensing of face masks, but until now, no extensive quantitative estimation exists for coastal regions. Linking behaviour dataset on face mask usage and solid waste management dataset, this study estimates annual face mask utilization and plastic pollution from mismanaged face masks in coastal regions of 46 countries. It is estimated that approximately 0.15 million tons to 0.39 million tons of plastic debris could end up in global oceans within a year. With lower waste management facilities, the number of plastic debris entering the ocean will rise. Significant investments are required from global communities in improving the waste management facilities for better disposal of masks and solid waste.

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China has been the major fishery producer in the Northwest Pacific Ocean for decades and the seafood safety deserves continuous concern. In this study, 188 organism and 27 sediment samples were collected from the Jiaozhou Bay, a typical semi-enclosed bay adjacent to the Northwest Pacific Ocean, to study the arsenic (As) pollution level and trophodynamics in the coastal regions of China combined with a meta-analysis. Results showed that arsenic was the most abundant in crustaceans with the average of 28.84 ± 4.95 mg/kg in dry weight, in comparison with molluscs (18.68 ± 2.51 mg/kg) and fish (9.31 ± 1.45 mg/kg). Additionally, based on a meta-analysis, arsenic in coastal organisms generally decreased from north to south in China. With increasing values of δ15N, arsenic was significantly biomagnified in the molluscs but bio-diluted in the groups of crustaceans and fish. When all the species were taken into consideration, overall bio-dilution of As was observed through the simplified food chain in the Jiaozhou Bay. Based on the target hazard quotient (THQ), the health risk of consuming seafood from the Jiaozhou Bay was not significant except for several kinds of crustaceans. The smaller THQs indicated lower health risk of eating molluscs and fish than crustaceans. Besides, urban households tended to undertake much higher risk than rural households. Based on our results, it is recommended for urban citizens to reduce the frequency of consuming crustaceans and give preference to fish when choosing seafood.

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In coastal regions, intense bursts of particles are frequently observed with high concentrations of iodine species, especially iodic acid (IA). However, the nucleation mechanisms of IA, especially in polluted environments with high concentrations of sulfuric acid (SA) and ammonia (A), remain to be fully established. By quantum chemical calculations and atmospheric cluster dynamics code (ACDC) simulations, the self-nucleation of IA in clean coastal regions and that influenced by SA and A in polluted coastal regions are investigated. The results indicate that IA can form stable clusters stabilized by halogen bonds and hydrogen bonds through sequential addition of IA, and the self-nucleation of IA can instantly produce large amounts of stable clusters when the concentration of IA is high during low tide, which is consistent with the observation that intense particle bursts were linked to high concentrations of IA in clean coastal regions. Besides, SA and A can stabilize IA clusters by the formation of more halogen bonds and hydrogen bonds as well as proton transfers, and the binary nucleation of IA-SA/A rather than the self-nucleation of IA appears to be the dominant pathways in polluted coastal regions, especially in winter. These new insights are helpful to understand the mechanisms of new particle formation induced by IA in clean and polluted coastal regions.

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Coastal regions, and in particular islands where precipitation from clouds formed out at sea occurs for the first time, are prime candidates for regions where 2H and 18O composition of precipitation will deviate significantly from the global mean geographic and physiographic trends of vapour-transport patterns. The results reported here are the outcome of a study that aimed to test this hypothesis by 'isotopographically' mapping the characteristic δ2H and δ18O signatures of Scottish freshwaters. The resulting isotope abundance landscapes or 'isoscapes' will underpin studies aiming to authenticate origin of Scottish produce but may also offer a baseline against which environmental changes could be assessed. Between April 2011 and May 2012 freshwater samples were collected from 127 different freshwater lochs and reservoirs across Scotland, and analysis results were compared to precipitation data provided by the British Geological Survey. Here we present the results of the 2H and 18O analyses of these water samples as well as the first detailed Scotland freshwater isoscapes with a grid resolution of about 5 × 5 km (0.05 degrees).

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Collaborative science brings together diverse stakeholders to share knowledge and form networks that in turn can be foundational to policies and practices to increase socio-ecological resilience. In this article we present results from a collaborative science project that employed collaborative learning methods to develop a network of local, regional, state and academic stakeholders. These stakeholders had little social interaction prior to the project, and represented a diversity of views, positions and responsibilities. They shared in common a concern for the effects of climate change on a coastal socio-ecological system and the desire to reduce vulnerabilities and enhance resilience. Through ethnographic and survey methods, we found that collaborative science and learning promoted the exchange of cultural and environmental knowledge and expertise among individuals who previously had no sustained interaction. Stakeholders perceived these exchanges as worthwhile in that they allowed individuals to express viewpoints and share knowledge and expertise, which was seen to have the potential to increase socio-ecological resilience. Our results suggest that social networks can emerge from collaborative science and learning projects, and can become formally organized and help foster opportunities to enhance socio-ecological resilience.

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Perfluoroalkyl acids (PFAAs) have been observed in various environmental matrices globally in recent years. In this study, the levels, spatial distribution tendencies, and partitioning characteristics of the target 12 PFAAs were investigated in water and sediment from the coastal regions of Shandong peninsula in China, and two sediment core samples were also collected to study the vertical and historical variation of PFAAs. The ranges (means) of total PFAA concentrations were 23.69-148.48 ng/L (76.11 ng/L) in the water and 1.30-11.17 ng/g (5.93 ng/g) in the surface sediment, respectively. Among the target 12 PFAAs, perfluorooctanoic acid (PFOA) was the dominant component in water, followed by perfluorooctane sulfonate (PFOS) and perfluorohexanoic acid (PFHxA). PFOS, perfluoroundecanoic acid, and PFOA were the dominant components in sediment. For their spatial distribution, higher levels of PFAAs were found at the locations close to much developed cities. The PFAA concentrations showed an overall decreasing tendency with depth increase in the two sediment cores, which indicates that the extent of PFAAs pollution is aggravating trend in recent years. Results of the partition coefficient (K d ) show that the compounds with longer carbon chains (C ≥ 7) generally had higher K d values, which suggest that long-chain PFAAs are prone to be adsorbed by sediment. In addition, the Log K d of PFHxA, PFOA, and PFOS were significantly and positively correlated to the salinity of the water. The results of risk assessment suggest appreciable risk of PFAAs to the local ecosystem.

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An osmotic detention pond was proposed for the management of urban runoff in coastal regions. Forward osmosis was employed as a bridge to utilize natural osmotic energy from seawater for concentrating and reusing urban runoff water, and as a barrier to reject runoff-derived contaminants. The process was demonstrated by a lab scale testing using synthetic urban runoff (as the feed solution) and synthetic seawater (as the draw solution). The submerged forward osmosis process was conducted under neutral, acidic and natural organic matter fouling condition, respectively. Forward osmosis flux decline was mainly attributed to the dilution of seawater during a semi-batch process in lab scale testing. However, it is possible to minimize flux decrease by maintaining a constant salinity at the draw solution side. Various changes in urban runoff water quality, including acidic conditions (acid rain) and natural organic matter presence, did not show significant effects on the rejection of trace metals and phosphorus, but influenced salt leakage and the rejection of nitrate and total nitrogen. Rejection of trace metals varied from 98% to 100%, phosphorus varied from 97% to 100, nitrate varied from 52% to 94% and total nitrogen varied from 65% to 85% under different feed water conditions. The work described in this study contributes to an integrated system of urban runoff management, seawater desalination and possible power generation in coastal regions to achieve a sustainable solution to the water-energy nexus.

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