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BACKGROUND: Malaria is transmitted by different Anopheles species. In Brazil, the disease is concentrated in the Amazon region. Rivers play an important role in the life cycle of malaria since the vector reproduces in aquatic environments. The waters of the rivers in the Amazon have distinct chemical characteristics, which affect the colour of the water and therefore, the study analysed whether the colour of the waters of the rivers have an on influence the distribution of malaria. The goal of the study was to correlate the different colourations of the water (black, white and mixed water) and the malaria incidence in 50 municipalities of the Amazonas state, Brazil, and then test hypotheses about the characteristics of the colour of the rivers and disease incidence. METHODS: This study was conducted for a period of seventeen years (2003-2019) in 50 municipalities in the state of Amazonas, Brazil. A conditionally Gaussian dynamic linear model was developed to analyse the association of malaria incidence and three types of river colour: white, black and mixed. RESULTS: The analyses indicate that the distribution of malaria is related to the colouration of the rivers. The results showed that places located near black-water rivers have a higher malaria incidence when compared to places on the banks of white-water rivers. CONCLUSIONS: Historically, the hydrological regime has played an important role in the dynamics of malaria in the Amazon, but little is known about the relationship between river colours and the incidence of the disease. This research was carried out in a region with hydrographic characteristics that were heterogeneous enough to allow an analysis that contrasted different colours of the rivers and covered almost the whole of the state of Amazonas. The results help to identify the places with the highest risk of malaria transmission and it is believed that they will be able to contribute to more precise planning of actions aimed at controlling the disease in the region.

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Removing ammonia from black water is one of the most urgent issues before it can be recycled as flushing water. In this study, an electrochemical oxidation (EO) process with commercial Ti/IrO2-RuO2 anodes to treat black water could remove 100% of different concentrations of ammonia by adjusting the dosage of chloride. Through the relationship between ammonia, chloride, and corresponding the pseudo-first-order degradation rate constant (Kobs), we could determine the chloride dosage and predict the kinetics of ammonia oxidation based on initial ammonia concentration in black water. The optimal N/Cl molar ratio was 1:1.8. The difference between black water and the model solution in terms of ammonia removal efficiency and oxidation products was explored. A higher chloride dosage was beneficial for removing ammonia and shortening the treatment cycle, but it also led to the generation of toxic by-products. Especially HClO and ClO3- generated in black water were 1.2 and 1.5 times more than the synthesized model solution under 40 mA cm-2. Through SEM characterization of electrodes and repeated experiments, the electrodes always maintained a high treatment efficiency. These results demonstrated the potential of the electrochemical process as a treatment method for black water.

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Recovery of phosphorus from wastewater through struvite crystallization is one of the most attractive methods. However, the cost of chemical consumption makes this technology is unattractive to some extent. In this work, highly active serpentine was prepared by one-step mechanical activation and then used to recover phosphate as struvite from the black water containing 132.8 mg/L phosphorus and 3144 mg/L ammonia nitrogen. The results indicated that the prepared active serpentine can release magnesium ions and hydroxide ions simultaneously into an aqueous solution and is an ideal raw material for struvite crystallization. The factors for phosphorus recovery in this process mainly include mechanical activation intensity, serpentine dosage, and contact time. For the actual black water, a high recovery rate of phosphorus (>98%) is achieved by using active serpentine as the magnesium and alkali source for struvite precipitation. The recovery product was identified as struvite with a median particle size of 32.96 µm. It was confirmed that the mechanical activation damaged the crystal structure of the raw serpentine, improving the activity of Mg2+ and OH-. The undissolved Si-containing particles act as crystal seeds, accelerating the struvite crystallization process. Furthermore, a pilot-scale test was conducted with a rural public toilet in Xiong'an New District, Hebei Province. The results showed that an acceptable phosphorus recovery (98%) could be achieved using active serpentine. Additionally, it was demonstrated that the serpentine process to recover phosphate as struvite reduced the cost by 54.4% in compared with an ordinary chemical process. The active serpentine is a promising dual source of magnesium and alkali for the phosphorus recovery by the struvite method. It has a potential prospect for the large-scale application in phosphorus recovery and struvite fertilizer production.

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The reuse of human wastes as biofertilizer resources offers a new option for meeting the growing demand for food and addressing poor soil productivity. Feces and black water are ubiquitous human wastes that usually require proper treatment, such as composting and anaerobic digestion, to remove potentially harmful substances before they can be applied as fertilizers. As an effective treatment technology for livestock farming wastes, the ectopic fermentation bed system (EFS) provides a new means of treating human waste and producing organic fertilizer from decomposed filler. Therefore, the objective of this study was to evaluate and compare the nutrient content and fertilizer potential of decomposed fillers obtained after EFS treatment of human feces and black water under different application conditions. The results showed that the application of fillers increased the yield of pakchoi by 3.60⁓29.32% and nutrient uptake by 8.09⁓83.45% compared to the CK, which could effectively promote the growth of pakchoi. This approach also improved the quality of pakchoi and enhanced soil fertility, and differences were observed in the effects of different kinds and application amounts of fillers. Soil EC was the soil property that had the greatest effect on the growth characteristics of pakchoi in this study. These findings help to better clarify the agronomic value of human wastes, but the effects of long-term filler application need to be further explored.

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With a 270 million Indonesian population, domestic wastewater is one of the major contributors to wastewater generated from human activities. This review aimed to give an overview of the current state of domestic wastewater generation, characteristics and treatment systems in Indonesia. Overall, grey water quantity in Indonesia was 1 to 4 times higher than black water quantity, while the quantity of untreated grey water was 3 to 6 times higher than untreated black water. Parameters of concern include suspended solids, biochemical oxygen demand, chemical oxygen demand, oil and grease, nitrogen and coliforms. Our analysis shows that grey water can be a significant source of water pollution due to the large quantity and lack of treatment. In addition, black water treatment that relies mainly on on-site treatment is often inadequate due to the lack of quality control for the infrastructure, operation and maintenance. An incentive or penalty scheme to build and ensure the quality of domestic wastewater treatment is required and can be applied at the household, community or central (city) level.

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Thermophilic and hyper-thermophilic anaerobic digestion (AD) are promising techniques for the treatment of concentrated black water (toilet fraction of domestic wastewater collected by low flush volume toilets; BW), recovery of nutrients and simultaneous pathogen removal for safe recovery and reuse of those nutrients. This study showed that thermophilic AD (55 °C) of concentrated BW reaches the same methanisation and COD removal as mesophilic anaerobic treatment of BW (conventional vacuum toilets) and kitchen waste while applying a higher loading rate (OLR) (2.5-4.0 kgCOD/m3/day). With a retention time of 8.7 days, and an OLR of >3 kgCOD/m3/day, COD removal of 70% and a methanisation of 62% (based on CODt) was achieved during thermophilic AD. Hyper-thermophilic (70 °C) reached lower levels of methanisation (38%). Start-up time of thermophilic AD was 12 days. And during thermophilic AD, a shift from acetoclastic methanogenesis towards syntrophic acetate oxidation was observed.

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The management of black water depends primarily on the knowledge of the dynamics of organic matter (OM), iron (Fe), sulfide (S), and manganese (Mn), at the water-sediment boundary (WSB). However, the mechanistic path of these substances leading to black water remains unsettled. In this study, a 35-day field study was conducted using the thin-film diffusion gradient technology (DGT) and the planar optrode to address the unknown combined effects of Fe, Mn, OM, S, and tannins from Eucalyptus species on Tianbao reservoir.Our results indicated that the hypolimnion was hypoxic due to thermal stratification, which caused the reduction of insoluble Fe and Mn from sediments to bottom water. Correlation analysis (Fe:S (r:0.5-0.9); Mn:S (r:0.2-0.8)) and elevated fluxes (Fe2+, Mn2+, S2-) connoted that these parameters interacted chemically to give black matter. The content of OM, Fe2+, and tannic acid in the benthic region diminished remarkably (p < 0.05) from day 1 (strong stratification) to day 35 (weak stratification), connoting that these parameters also interacted chemically to give black matter. The turbidity (clarity of the water) increased from day 1 to 35 with a significant difference (p < 0.05) recorded on day 14 confirming that black water was formed on this day when the thermal structure of the reservoir was annihilated. Correlation analysis supported the assertion that the variability in oxygen and redox conditions caused changes in Fe, Mn, and OM content at the WSB.The finding from the field research provides useful information to stakeholders on how to improve the quality of freshwater management designs.

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Using daily survey and monitoring "black water event" (BWE) results in the sensitive area of Lake Taihu from April to October, 2009-2018, as well as the BWE analyzed data for relative meteorological, hydrological, chemical, and algal bloom conditions, the characteristics and yearly differences of BWEs were summarized. A BWE control strategy was suggested. There were 75 BWE occurrences detected in the past 10 years. The average area of a BWE was 1.35 km2, with a maximum area of 9.20 km2. The BWEs lasted for an average of three days, while the longest lasted 16 days. The BWEs significantly increased organic matter, total nitrogen, total phosphorus, ammonia, and sulfate, among others. All the BWEs occurred at water temperatures over 20℃. All the BWE occurrences started between May and September. The yearly BWE intensity (BWEI) varied significantly among years, with the strongest intensity in 2017 and the second strongest in 2018. The BWEI was significantly positively related to yearly algal bloom intensity (ABI) and average daily water temperature from May to September, while there was no significant relationship with major nutrient indicators. This suggests that climatic variation among years will significantly influence the risk of a BWE in Lake Taihu. The occurrence of a BWE was significantly influenced by a polluted river mouth. Almost all the BWEs occurred near river mouths, except for five macrophyte-related BWEs. This suggests that sediment pollution and its resuspension could be strongly related to the occurrence of a BWE. When considering degradation factors, a BWE could be classified as an algal-related BWE and a macrophyte-related BWE. The algal-related BWE could be further classified into three types:river-related BWE, bloom transport BWE, and local origin BWE. This research suggests that algal bloom control will be the fundamental countermeasure to decrease the risk of a BWE. Bloom abatement treatments, including mechanical bloom cleaning, water current adjustment engineering, coast-away bloom cleaning engineering, mechanical aeration treatment, and sediment dredging near river mouths would be effective methods to abate the risk of a BWE.

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The accumulation of manganese in drinking water distribution systems often causes problems of "black water" in customers' taps. In this study, Mn accumulation onto a pipe surface under chlorinated conditions was investigated by focusing on the different states of Mn in the water. Lab-scale experiments suggested that the accumulation process included both the attachment of particulate Mn onto the surface (i.e., physical pathway) and the autocatalytic oxidation of Mn ions on the surface (i.e., chemical pathway). Based on the experimental results, a numerical model of Mn accumulation on the pipe surface via the two pathways was established. According to the model predictions, the physical pathway contributed less than the chemical pathway over time since the latter accelerated as Mn accumulation increased. The chemical pathway contributed 94% when the concentration of total Mn was 10 µg/L throughout the experiment, but only 67% when the concentration was 100 µg/L. Thus, the chemical pathway was more important for low concentrations of total Mn. In addition, the type of pipe materials used only influenced the physical pathway, while the presence of bromide directly enhanced the chemical pathway. In conclusion, limiting the chemical pathway was suggested as an effective strategy for reducing Mn accumulation during long-term operation, which is achieved by controlling the state of Mn in finished water.

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Tianbao reservoir in southern China (surrounded by Eucalyptus plantation) serves as a source of drinking water for the inhabitants. However, the reservoir water experiences black water (BW) of which the cause remains unclear. In this study, field observation and simulated laboratory experiment were conducted to understand the cause of the BW. The diffusive gradient in thin-film (DGT) device monitored the spatial changes in concentration of iron (Fe2+), manganese (Mn2+), sulfide (S2-), and dissolved organic carbon (DOC) at the SWI. The planar optode (PO) showed that hypoxia contributed immensely to the high positive fluxes Fe2+, Mn2+, and S2- measured, which co-precipitated to form black materials (FeS and MnS) at the SWI. The co-precipitation between Fe-S and Mn-S was supported by their significant positive correlation (Fe-S: r > 0.05, p < 0.05, Mn-S: r > 0.2, p < 0.05). Significant reduction (p < 0.05) in tannins concentration from November (strong thermal stratification) to December (weak thermal stratification) indicated that Fe2+ and tannins reacted during the mixing of reservoir water in December due to weak stratification. The simulated experiment confirmed that fresh Eucalyptus leaves produces a significant (p < 0.05) amount of tannins during hypoxia and reacts with Fe2+ to produce black water. A high positive correlation (r > 0.8) between Fe2+ and DOC demonstrated that Fe2+ and DOC combined and contributed to the reservoir water blackening. The study provides a better understanding on the impact of Eucalyptus plantation on water quality and provide guidance for scientific planting of Eucalyptus plantation in reservoir basins in southern China to ensure safe drinking water.

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The efficacy of CocoBear™ Larvicidal Oil and Aquatain® AMF Liquid Mosquito Film against larval and pupal Culex quinquefasciatus was compared (at maximum label field application rates) when applied to concrete troughs treated with composted cow manure. At 1 h posttreatment, CocoBear provided significantly greater reduction of mosquito larvae than Aquatain, but both products were equally effective in producing >97% control at 24 h. Each product provided >98% pupal reduction at 1 h posttreatment, with complete elimination of pupae from troughs at 24 h. CocoBear and Aquatain proved to be equally effective against Cx. quinquefasciatus immatures in organically enriched aquatic habitats.

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In South Korea, the installation of septic tanks for treating black water (STBW) is regulated even in sewage treatment areas to prevent the black water deposition in combined sewers. STBWs in which black water is anaerobically decomposed generate high concentrations of hydrogen sulfide (H2S). In this study, an immobilized media of sulfur-oxidizing bacteria (SOB) was used to remove the H2S. SOB media was prepared by using activated sludge collected from a wastewater treatment plant. Prior to field application, an appropriate cultivation period and aeration rate for SOB activation were estimated through a laboratory-scale test. The SOB was activated after a 23-day cultivation period and an aeration rate of 0.25 L-water/L-air/min. Moreover, the maximum H2S removal efficiency was observed at a cultivation period of 43 days and an aeration rate of 0.38 L-water/L-air/min. Then, the SOB media was installed on STBWs of various capacities. The H2S removal efficiency was compared between with and without SOB media. The maximum H2S elimination capacity with SOB media was 12.3 g/m3/h, which was approximately three times higher than without SOB media. Furthermore, the energy efficiency and oxidation rate were also three times higher with SOB, demonstrating the applicability of SOB for H2S removal in STBW.

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Black water is highly concentrated human waste water but represents only a minor portion of domestic sewage. A modified type of anaerobic baffled reactor (ABR) was studied to assess its potential for pretreating black water in rural China. The classification of microbial structure was also investigated to confirm its potential in application. The structure of the ABR was modified according to demand for application in practice. A hydraulic retention time (HRT) of 48 h was chosen as the optimal HRT after comparison among 24 h, 36 h, 48 h, and 72 h. Under the 48 h HRT, the ABR achieved average removal efficiencies of 94.05% of chemical oxygen demand (COD), 28.78% of total nitrogen (TN), 14.21% of ammonium nitrogen (NH4+-), and 32.54% of total phosphorus (TP) during 112 days of continuous operation. Samples from three different compartments were collected after 60-day continuous operation for bacterial and archaeal community investigation by 16S rRNA. Abundant degradation-related bacteria and methanogenic archaea were found in the ABR. The three samples had similar bacterial compositions at phylum, class, and genus levels, but the percentages of bacteria differed among the compartments. The distribution of archaea showed succession with the flow direction. In general, the ABR shows good performance under an HRT of 48 h and shows good potential for practical application.

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Black runoff occasionally flows from cutover areas of Eucalyptus plantations, polluting rivers and ponds, and resulting in fish death in severe cases. However, the occurrence patterns and environmental impacts of this black water remain unclear. Herein, we analyzed the major characteristics of black water at the occurrence sites, tested the complexation reaction of ground eucalyptus leaves with a solution of Fe3+, and determined the color and absorbance of the complex solution. The results showed that the water was dark blue, with weak acidity and strong light absorbance. The water contained a high level of dissolved organic matter content, while its chemical oxygen demand, total N, total P, NO3--N, and NH4+-N concentrations were significantly higher than those in the stream water from Eucalyptus, Pinus massoniana Lamb., and Cunninghamia lanceolata stands during the growth period. Additionally, the tannic acid concentration in the black water was 1.0 mg L-1 higher than that in the stream water from the Eucalyptus stand. The input of black water increases the concentration of tannic acid and NH4+-N, and the degradation of organic matter consumes dissolved oxygen in downstream ponds, leading to fish deaths. The presence of fresh logging residues and hot, humid weather also enable black water formation. Field investigations and simulation experiments revealed fresh Eucalyptus residues decompose rapidly under high-temperature and rainfall conditions, releasing large amounts of tannic acid, which reacts with Fe3+ to form a dark blue tannic acid­iron complex and results in black water. These results indicate that the rich Fe3+ in runoff may be a key factor in the occurrence of black water. The logging of Eucalyptus plantations during the dry season or on non-rainy days and a reduction in the logging area could prevent the occurrence of black water or mitigate the extent of its environmental hazards.

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The world's richest freshwater fish community thrives in gradients of contrasting environments in Amazonia, ranging from ion-poor acidic black waters, to ion-rich circumneutral white waters. These hydrochemical gradients structure Amazonian fish assemblages via ecological speciation events. Fish bacterial communities contain an important genetic heritage essential for their hosts' survival and are also involved in adaptive divergence via niche adaptation processes, but the extent to which they evolve in response to hydrochemical gradients in Amazonia is unknown. Here we investigated bacterial communities (gut and skin mucus) of two ecologically and phylogenetically divergent host species (Mesonauta festivus and Serrasalmus rhombeus) distributed throughout these hydrochemical gradients. The goal was to characterize intra- and interspecific Amazonian fish microbiome variations across multiple scales. Using a 16S metabarcoding approach, we investigated the microbiota of 43 wild M. festivus, 32 S. rhombeus and seven water samples, collected at seven sampling sites encompassing both water colours. Taxonomical structures of bacterial communities from both host species were significantly correlated to the environmental continua of magnesium, sodium, dissolved organic carbon, calcium, dissolved O2 , pH, potassium, hardness and chloride. Analysis of discriminating features in community structures across multiple scales demonstrated intra- and interspecific structural parallelisms in the response to the hydrochemical gradients. Together, these parallelisms suggest the action of selection on bacterial community structures along Amazonian hydrochemical gradients. Functional approaches along with reciprocal transplant experiments will provide further insights on the potential contribution of Amazonian fish microbiomes in host adaptation and ecological speciation events.

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Large dams built for hydroelectric power generation alter the hydrology of rivers, attenuating the flood pulse downstream of the dam and impacting riparian and floodplain ecosystems. The present work mapped black-water floodplain forests (igapó) downstream of the Balbina Reservoir, which was created between 1983 and 1987 by damming the Uatumã River in the Central Amazon basin. We apply remote sensing methods to detect tree mortality resulting from hydrological changes, based on analysis of 56 ALOS/PALSAR synthetic aperture radar images acquired at different flood levels between 2006 and 2011. Our application of object-based image analysis (OBIA) methods and the random forests supervised classification algorithm yielded an overall accuracy of 87.2%. A total of 9800 km2 of igapó forests were mapped along the entire river downstream of the dam, but forest mortality was only observed below the first 49 km downstream, after the Morena rapids, along an 80-km river stretch. In total, 12% of the floodplain forest died within this stretch. We also detected that 29% of the remaining living igapó forest may be presently undergoing mortality. Furthermore, this large loss does not include the entirety of lost igapó forests downstream of the dam; areas which are now above current maximum flooding heights are no longer floodable and do not show on our mapping but will likely transition over time to upland forest species composition and dynamics, also characteristic of igapó loss. Our results show that floodplain forests are extremely sensitive to long-term downstream hydrological changes and disturbances resulting from the disruption of the natural flood pulse. Brazilian hydropower regulations should require that Amazon dam operations ensure the simulation of the natural flood-pulse, despite losses in energy production, to preserve the integrity of floodplain forest ecosystems and to mitigate impacts for the riverine populations.

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Depleted oxygen (O2) in the sediment and overlying water of malodorous black water poses a potential threat to aquatic ecosystems. This study presents a method for sustainable regulation of the dissolved oxygen (DO) levels towards the malodorous black water. Oxygen-loaded natural porous materials were prepared by vacuum degassing to remove air from the pores and fill them with pure O2. Capping anaerobic sediment with the prepared 6 oxygen-loaded porous materials was effective in prompting the DO concentration of the malodorous black water. Although granules activated carbon (GAC) displayed the highest oxygen-loading capability, oxygen-loaded volcanic stone additive was more efficient for long-lasting combating of the anaerobic condition because the DO level at sediment-water interface (SWI) and the DO penetration depth showed approximately 5.38- and 3.75-fold increase, respectively, compared with the untreated systems. The improvement in DO was substantially enhanced in the presence of submerged macrophyte (Vallisneria natans), during which the release of O2 from oxygen-loaded volcanic stone facilitated the plant growth. With the joint efforts of the O2 released from volcanic stone and photosynthesis by the macrophytes, the DO levels were maintained at approximately 6.80 mg/L after a 41-day incubation, which exceeded (P < 0.05) the value in only oxygen-loaded volcanic stone or macrophytes added treatments. In addition to the elevated DO level, the combined employment of oxygen-loaded volcanic stone and macrophytes triggered a negative ammonia (NH4+-N) flux across the SWI and an 85.82% reduction of methane (CH4) production compared with those without treatment, accompanied by a decrease in total inorganic carbon and a 2.55- fold increasing of submerged macrophyte biomass, which is presumably attributed to nitrification, remineralization, and assimilation. The results obtained here shed a degree of light on the sustainable modulation of the anaerobic condition in malodorous black water.

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Water system degradation has a severe impact on daily life, especially in developing countries. However, microbial changes associated with this degradation, especially changes in microbes related to sulfur (S) cycling, are poorly understood. In this study, the abundance, structure, and diversity of sulfate-reducing microorganisms (SRM) and sulfur-oxidizing microorganisms (SOM) in the sediments from the Ziya River Basin, which is polluted by various human interventions (urban and agricultural activities), were investigated. Quantitative real-time PCR showed that the S cycling-related (SCR) genes (dsrB and soxB) were significantly elevated, reaching 2.60 × 107 and 1.81 × 108 copies per gram of dry sediment, respectively, in the region polluted by human urban activities (RU), and the ratio of dsrB to soxB abundance was significantly elevated in the region polluted by human agricultural activities (RA) compared with those in the protected wildlife reserve (RP), indicating that the mechanisms underlying water system degradation differ between RU and RA. Based on a 16S rRNA gene analysis, human interventions had substantial effects on microbial communities, particularly for microbes involved in S cycling. Some SCR genera (i.e., Desulfatiglans and Geothermobacter) were enriched in the sediments from both RA and RU, while others (i.e., Desulfofustis and Desulfonatronobacter) were only enriched in the sediments from RA. A redundancy analysis indicated that NH4 +-N and total organic carbon significantly influenced the abundance of SRM and SOM, and sulfate significantly influenced only the abundance of SRM. A network analysis showed high correlation between SCR microorganisms and other microbial groups for both RU and RA, including those involved in carbon and metal cycling. These findings indicated the different effects of different human interventions on the microbial community composition and water quality degradation.

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To assess how the quality and properties of the natural dissolved organic carbon (DOC) could drive different effects on gill physiology, we analysed the ionoregulatory responses of a native Amazonian fish species, the tambaqui Colossoma macropomum, to the presence of dissolved organic carbon (DOC; 10 mg l-1 ) at both pH 7.0 and pH 4.0 in ion-poor water. The DOC was isolated from black water from São Gabriel da Cachoeira (SGC) in the upper Rio Negro of the Amazon (Brazil) that earlier been shown to protect a non-native species, zebrafish Danio rerio against low pH under similar conditions. Transepithelial potential (TEP), net flux rates of Na+ , Cl- and ammonia and their concentrations in plasma and Na+ , K+ ATPase; v-type H+ ATPase and carbonic anhydrase activities in gills were measured. The presence of DOC had negligible effects at pH 7.0 apart from lowering the TEP, but it prevented the depolarization of TEP that occurred at pH 4.0 in the absence of DOC. However, contrary to our initial hypothesis, SGC DOC was not protective against the effects of low pH. Colossoma macropomum exposed to SGC DOC at pH 4.0 experienced greater net Na+ and Cl- losses, decreases of Na+ and Cl- concentrations in plasma and elevated plasma ammonia levels and excretion rates, relative to those exposed in the absence of DOC. Species-specific differences and changes in DOC properties during storage are discussed as possible factors influencing the effectiveness of SGC DOC in ameliorating the effects of the acid exposure.

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To reduce fresh water load on ships, seawater can be used for toilet flushing on-board. And saline black water was treated on-site by bioaugmentation original marine bacteria with Pseudoalteromonas sp. SCSE709-6 (P. sp. SCSE709-6) to prevent marine pollution. In the batch experiments, P. sp. SCSE709-6 was effective in nutrient removal, which was not closely related to the amount of inoculation. In the on-board continuous experiments, the systems inoculated with P. sp. SCSE709-6 possessed excellent TP removal ability (removal rate: 80.93% for T3 and 88.39% for T4). The inoculum of P. sp. SCSE709-6 changed the microbial community structure and increased the similarity of microbial communities. P. sp. SCSE709-6 had a significant influence on the performance and microbial community of the systems. This study strongly proposes that the P. sp. SCSE709-6 is a promising alternative in saline black water treatment, which has great significance to the practice of on-board seawater flushing toilet.

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