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To identify the influences of anthropogenic activities on the composition, spatial distribution, sources, and transformation mechanism of sedimentary fulvic acid (FA) fractions from different reaches of an urban river were tracked via excitation-emission matrix (EEM) fluorescence spectroscopy with parallel factor (PARAFAC) analysis and two-dimensional correlation spectroscopy (2D-COS). Sediment samples were collected from Baitapu River (BR) along gradients with human activities (e.g., rural, town, and urban sections) in Shenyang, northeast China, from which FA fractions were extracted and then determined via EEM fluorescence spectroscopy. According to optical indices, the autochthonous sources of sedimentary FA fractions in BR were more significant than the terrestrial sources. Among the sections, the contribution from autochthonous sources decreased in the following order: Rural > Urban > Town. Six components of sedimentary FA fractions were identified via EEM–PARAFAC: C1 comprised tryptophan-like (TRL) compounds; C2 was associated with microbial humic-like (MHL) compounds; C3, C4, and C5 were associated with FA-like (FAL) compounds; and C6 comprised humic acid-like (HAL) compounds. The proportion of sedimentary FA fractions decreased in the following order: MHL + FAL + HAL (humus, 77.37–88.90%) > TRL (protein, 11.10–22.63%) for the three sections, showing that humus dominated. The town section exhibited the highest sedimentary FA fractions (5328.87 ± 1315.82 Raman unit [R.U.]), followed by the urban (4146.49 ± 535.75 R.U.) and rural (2510.56 ± 611.00 R.U.) sections. Three pollution sources were determined via principal component analysis (i.e., the dominant industrial source, domestic wastewater, and agricultural effluent). Additionally, the results from 2D-COS revealed that sedimentary FA fractions tended to stabilize as the protein-like component was transformed into the HAL component. Furthermore, we used the structural equation model to validate the critical environmental variables affecting the FA fraction transformation. The results can elucidate the influences of human activities on the dynamics of sedimentary FA fractions in urban rivers. [ABSTRACT FROM AUTHOR]

Background: Spatio-temporal variations of structural components of the POM–DOM fractions exhibit in urban rivers, which is valuable information to reveal dynamic migration and transformation within and between the organic matter pools, also provide important support for river water quality improvement and management measures. Second derivative UV–visible spectroscopy (SDUVS) was applied to simultaneously characterize structural components and spatial variations of dissolved (DOM: Diameter < 0.2 μm) and particulate (POM1: 0.2 < diameter < 0.7 μm; POM2: diameter > 0.7 μm) organic matters in an urbanized river of northeast China. Results: Thirty-six water samples were collected from mainstream and tributaries along a human impact gradient, i.e., rural, town and urban regions. The DOM was a representative fraction for the natural organic matter pool, which was mostly derived from allochthonous and terrestrial sources. Four components C1 to C4 were identified from the POM–DOM fractions by the SDUVS. The C1 associated with phenolic groups and the C2 related to carboxylic groups were dominant for the organic matter pool. The C3 was composed of the primary humificated materials, and the %C3 was kept relatively consistent in the organic matter pool. The C4 presented deeply humificated organic matter with the increase of aromatic and alkyl structures. The average %C4 of the POM pool was higher than that of the DOM pool, indicating that the humification degree of the POM fractions was higher than that of the DOM fraction. Conclusions: Moreover, the tributaries had a higher average %C4 within the DOM than the mainstream, and trends of the POM pool were similar to the DOM pool. The trophic level of the river water decreased in the order of urban region > town region > rural region, while the molecular sizes of the POM–DOM decreased in the order of rural region > town region > urban region. [ABSTRACT FROM AUTHOR]

UV-visible absorption spectroscopy coupled with principal component analysis (PCA) and hierarchical cluster analysis (HCA) was applied to characterize spectroscopic components, detect latent factors, and investigate spatial variations of dissolved organic matter (DOM) in a large-scale lake. Twelve surface water samples were collected from Dongjianghu Lake in China. DOM contained lignin and quinine moieties, carboxylic acid, microbial products, and aromatic and alkyl groups, which in the northern part of the lake was largely different from the southern part. Fifteen spectroscopic indices were deduced from the absorption spectra to indicate molecular weight or humification degree of DOM. The northern part of the lake presented the smaller molecular weight or the lower humification degree of DOM than the southern part. E, E, E, and S were latent factors of characterizing the molecular weight of DOM, while E, E, E, E, E, and A were latent factors of evaluating the humification degree of DOM. The UV-visible absorption spectroscopy combined with PCA and HCA may not only characterize DOM fractions of lakes, but may be transferred to other types of waterscape. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl acids (PFAAs) in Daliao River system were simultaneously determined by UPLC-MS/MS coupled with SPE for water samples and with ultrasonication extraction for sediments. All samples were collected from the mainstreams of Hun River (HR) and Daliao River (DLR), as well as urban canal Xi River (XR) in Shenyang City, located in northeast China. Under the optimal conditions, the recoveries of most selected PFAAs were 61-131 % with RSD below 30 % for spiked water and sediment samples. The total average concentrations of PFAAs in surface water were 1.76-9.47 ng/L in the HR, 9.54-13.0 ng/L in the DLR and 33.5-50.7 ng/L in the XR. As the dominant PFAAs, perfluorooctanoic acid (PFOA) was detected at levels from 1.52 to 7.12 ng/L in the HR and DLR. PFOA, perfluoropentanoic acid (PFPA) and perfluorooctane sulfonic acid (PFOS) were the most abundant compounds detected in the XR with concentration ranges of 6.71-18.1, 9.7-26 and 0.81-13 ng/L, respectively. The average concentration of PFAAs in the sediments followed the sequence of the XR > DLR > HR. Perfluorodecanoic acid (PFHxA) was the dominant PFAA detected in 76.5 % of the sediment samples from the three rivers, with the concentrations of 0.07-0.49 ng/g dry mass. Both PFOS and PFOA were measurable in the sediments on very few occasions, with the concentration up to 0.84 ng/g dry mass. The calculated average partition coefficients (Log K, L/kg) of PFOA and PFOS between the sediment and water were 1.18 and 2.21, respectively. Given their exposure levels and risk quotient (RQ) values, PFOS and PFOA had no significant risk to aquatic organisms in the DLR system. [ABSTRACT FROM AUTHOR]

Potential water pollution derived from melting snow is a growing concern to watershed management in northern climates. For most small watersheds in the Hun River Basin, substantial portions of the annual load of pollutants such as organic matter, ammonia, phosphorus and metals come from snowmelt and early spring runoff. Thus, the annual spring flood is a real threat to the trophic state and water quality of Hun River. By three-dimensional fluorescence technology, the composition and characteristics of dissolved organic matter (DOM) in early spring runoff of a small watershed (the Baitapu River) were analyzed, and the correlation with land use was investigated. The result showed that compared with NH-N and TP, DOM was not the major contributor to water quality deterioration in spring flooding, but its composition still presented significant differences. Compared with that in medium flow period, the abundance of a soluble microbial byproduct-like material in the spring-flood period decreased from 28.6 to 15.8 %, while those of tyrosine-like material and humic-like material increased from 36.0 and 1.8 % to 44.4 and 10.7 %, respectively. DOM in spring flooding had a relatively higher aromaticity degree, a greater humification level, and a larger molecular weight. Meanwhile, DOM from urban areas contained more tyrosine-like material. For the Baitapu River, urban areas were the major DOM source in both the medium flow period (from dispersed point sources) and the spring flood period (from a wastewater treatment plant). Therefore, DOM composition can be used as an effective indicator for tracking pollution sources. [ABSTRACT FROM AUTHOR]

The Xi River (XR) and Pu River (PR) are the tributaries of Hun River Watersheds (HRW), located in Liao River Basin (LRB), northeast China. These riverine waters are historically polluted by effluents from printing and dyeing enterprises, and pharmaceutical and chemical industries. The concentrations of phthalic acid esters (PAEs), e.g., dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), di- n-octyl phthalate (DNOP) and bis(2-ethylhexyl) phthalate (DEHP), as well as phenols including phenol, 4-methylphenol, 2,3-dimethylphenol, 2,4-dimethylphenol, 3,5-dimethylphenol, 2,4,6-trimethylphenol, 2,4-di- tert-butylphenol and 2,6-di- tert-butyl-4-ethylphenol in surface water of the XR and PR were determined by gas chromatograph (GC) coupled with a mass spectrometer (MS), respectively, during spring (dry), summer (wet) and autumn (normal) seasons. DMP, DIBP, DBP, phenol, 4-methylphenol and 3,5-dimethylphenol were identified as the dominant pollutants in the XR, and DBP, DIBP, DEHP and phenol were the main pollutants in the PR. Seasonal variations of the geometric mean concentrations in the XR ranged from 6.88 to 19.5 μg/L for ∑PAEs and 24.5-1195 μg/L for ∑phenols with the highest level in summer. The temporal distribution of ∑PAEs or ∑phenols in the PR was similar to that in the XR, i.e. the highest levels were observed in summer (24.1 μg/L for ∑PAEs and 26.8 μg/L for ∑phenols).The concentrations of pollutants were highly variable across sampling sites. The geographic concentrations of ∑PAEs were in the range of 9.92-17.9 μg/L in the XR and 7.42-37.6 μg/L in the PR. As for ∑phenols, the greater spatial variations were observed, ranging from 14.0-2008 μg/L in the XR and from 4.00 to 80.5 μg/L in the PR. Cluster analysis (CA) showed that the 19 sampling stations were divided into three clusters: cluster A was made up of the majority of sampling sites in the PR, slightly polluted by PAEs and phenols; cluster B consisted of the sites from both the XR and PR; cluster C included the sampling sites in the XR, where was heavily polluted by PAEs and phenols. [ABSTRACT FROM AUTHOR]

The water quality (COD as an index) in the Liao River basin (LRB) has been significantly improved in recent years, but toxic organic pollutants and heavy metals, however, are still present. Due to their bio-accumulative, persistent and poorly biodegradable properties as well as carcinogenic, teratogenic and mutagenic effects, these pollutants have caused severe water environment pollution in the LRB and threatened to human health. This paper reviewed the pollution levels of PAHs, OCPs, PCBs, emerging persistent organic pollutants and heavy metals in the LRB. The quantitative source apportionment methods and their application in LRB were summarized in detail. It was indicated that the organic pollutants and heavy metals in the LRB mainly originated from industrial sources, municipal wastewaters and agricultural nonpoint sources. The main problems and some suggestions for future study were proposed in order to acquire systematic data sets and comprehensive information on water pollution characteristics, which would provide valuable basis for government to establish an efficient strategy on prevention and control of highly toxic organic pollutants and trace heavy metals in the LRB. [ABSTRACT FROM AUTHOR]

Due to rapid economic development and population growth, China is facing severe water problems that include sea-level rise and increasing salinization, floods, water pollution, water shortage, soil erosion and ecosystem deterioration, as well as biodiversity loss. In recent decades, China is progressively more concerned with its water issues that are now at the center of social and political attention. Having to overcome similar challenges, Germany has taken a leading role in the field of water sciences and technology. In particular, China can benefit from the lessons learnt in Germany concerning the rehabilitation of water resources in areas heavily affected by chemical industry and mining after the reunification in 1989. German-Chinese cooperation in water sciences started over 25 years ago and dealt with increasing challenges in the 21st century. Following the open space workshop during the Water Research Horizon Conference in Berlin 2014, this article provides a view of some of the challenges and potential opportunities of German-Chinese cooperation in water science and technology. [ABSTRACT FROM AUTHOR]

Purpose: Chemometric methods were used to analyze chemical/spectroscopic data of fulvic acid (FA) isolated from soils in Hetao Irrigation District of China and to indicate humification degree of soil organic matter and assess soil salinization processes. Materials and methods: Composite soil samples of different depths were collected from native halophyte soils and furrow-irrigated fields along a saline impact gradient, namely, Comm. Salicornia europaea (CSE), Comm. Suaeda glauca (CSG), Comm. Kalidium cuspidatum (CKC), Comm. Sophora alopecuroides (CSA), corn fields (CFDs), and wheat fields (WFDs). Results and discussion: Humification indices (HIXs) deduced from elemental composition and fluorescence spectroscopy were better in assessing humification degree of FA than those from UV-visible spectroscopy. Soil samples were clustered into five groups, indicating that the humification degree of FA isolated from the CSE soil was the lowest, followed by CSG and CKC, CSA, CFD, and WFD. Exchangeable sodium percentage (ESP) closely exhibited linear correlations with the HIXs, and the humification degree decreased with a rise in ESP. Conclusions: The results obtained by chemometrics justified that HIXs not only could identify humification degree of soil organic matter but also could assess soil salinization processes. [ABSTRACT FROM AUTHOR]

Abstract: The problem of petrochemical wastewater pollution is quite serious in Liaoning province of China. Evaluation based on current water treatment technologies is of significance for the improvement of water quality. Research on multi- level comprehensive mathematical evaluation model considering both sewage treatment effect and technical economic benefits would do great help to the implementation and construction of water pollution treatment process. The fuzzy & grey comprehensive method and the technology cost-benefit analysis method were used for evaluation of water treatment technologies applied in the petrochemical industry, based on statistical data in 2009 in Liaoning province of China. It is concluded that the most suitable technologies to treat petrochemical waste water are traditional biological filter method and biological aerated filters method. [Copyright &y& Elsevier]

To compare the structure of microbial community in the oily wastewater treatment plants (OWWTPs) located in China, and to discern the impacts of environment variables on the variance of microbial community, activated sludge samples from six typical OWWTPs were taken and the structure of microbial community of these six samples were analyzed via Illumina high-throughput sequencing. 18 core genera including Comamonas , Bacillus , Pseudomonas , Thauera , Paenibacillus , etc. were shared by all OWWTPs. Canonical correspondence analysis (CCA) suggested that temperature, oil concentration, DO and pH exhibited significant impacts in shaping the structure of microbial community. Variance partitioning analyses (VPA) illuminated that the most variation in microbial community was contributed to geographic location, explaining 36.4% of the total variations obtained, followed by wastewater characteristics (18.7%) and operational parameters (8.6%). This work offered insights into the structure of microbial community in OWWTPs at different geographic locations and illustrated the correlations between environment variables and microbial community in OWWTPs. Image 1 • Community structure in different oily wastewater treatment plants was compared. • Effects of environmental variables on the community variation were discerned. • Bacterial community variance strongly correlated with temperature, oil, DO and pH. • Geographic location (36.4%) had the greatest contribution to community variance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The NPS pollution loads in the PYLB were concentrated from April to June. • The Grain for Green Project has some impact on the NPS pollution in the PYLB. • The NPS pollution risk can be well assessed by the grey water footprint theory. Non-point source (NPS) pollution has gradually become the main source of water environmental pollution with the rapid economic development during the recent decades, especially for the economically developed Yangtze River Basin of China. Due to rapid urbanization, the pressure of the water environment in the Poyang Lake basin (PYLB) has been increasing. In this study, the spatial and temporal variations of NPS pollution loads including total nitrogen (TN) and total phosphorus (TP) in the PYLB during the period 2003–2012 were firstly investigated by using the SWAT; then the changes in NPS pollution loads under different land use types were identified by using the SWAT, land use transition matrix, statistical analysis and scenario analysis methods; finally, the NPS pollution risk assessment were achieved by means of the grey water footprint theory. The results showed that the NPS pollution loads in the PYLB were concentrated from April to June with a large inter-annual variability. The Gan River basin contributed the largest proportion of pollutants entering into the Poyang lake while the Xiu River basin produced the smallest pollution loads. Under the background of the policy of "Grain for Green Project" since 2002, the areas of cultivated land, grassland and bare land decreased during the period 2000–2010, while those of forest land and settlement increased. As the main source of NPS pollution, the area of cultivated land has decreased, while the unit load intensity under cultivated land has significantly increased. By calculating the annual GWF of TN and TP loads and their corresponding WPL, which all showed an upward trend. The results obtained in this study have practical significance for reducing the NPS pollution loads in the PYLB and controlling the environmental pollution in the Yangtze River. [ABSTRACT FROM AUTHOR]

Phosphorus is the primary eutrophication cause of river, lake, reservoir and estuary and it may be one of the principal pollutants for the agricultural watershed with middle and small cities. The sediment and phosphorus loads, related migration paths and contribution of source regions to receiving waters at different sections of a river basin are not clear. The modified Soil and Water Assessment Tool (SWAT) model was utilized to investigate the phosphorus loads and the relationships among water resources, sediment, and phosphorus loads in one of the important tributaries of the Three Gorge Reservoir (TGR) of China, and to investigate the retention dynamics of phosphorus in the river continuum and the influencing factors. It showed that under the scenario of rice terraces and ponds, the annual sediment loss and total phosphorus load were 125t and 2.5t, being reduced by 40%–80% compared to the natural slope scenario; the daily peak value of suspended sediment load was reduced by 30%–75%, and the relationship between the rainfall and runoff was weakened slightly; the retention rate of phosphorus sources reached 40%–78%. The results confirm that the rice terraces and ponds have altered local hydrological conditions, enhanced a substantial water, sediment, and phosphorus retention capacity that is highly consistent over time and space scales, thereby altering the predominant forms of phosphorus and improving the environmental resilience in soil and nutrition loss for the hilly watershed of the TGR. • Phosphorus and sediment loads are quantitative analyzed in a typical hilly watershed of TGR. • Rice terraces and ponds reduce the particle phosphorus concentration and flux up to 80%. • Response relationship among the flow, sediment and TP in different land use are altered at different degree. • Rice terraces and ponds improved the local environment residence at moderate and relative heavy rainfall. [ABSTRACT FROM AUTHOR]

[Display omitted] • Total absolute principal coefficient was applied to identify the key region of EEM. • DOM in the crop and halophyte topsoils was predominantly derived from microbial sources. • ESP primarily affected C1 in the CRLD but influenced C1 and C2 both in the XYCY and HACY. Soil dissolved organic matter (DOM) is crucial for soil formation as well as the global biogeochemical cycle. Land use plays a substantial impact on the composition structure of soil DOM, while the linkage between soil DOM fractions and land use is still rarely studied. Here, sixteen topsoil samples were collected from cropland (CRLD), xylophyta community (XYCY) and halophyte community (HACY) in Hetao irrigation area of China. Three-dimension excitation-emission matrix fluorescence spectroscopy (EEM) conjunct absolute principal component coefficients (PC coefficients), parallel factor analyses (PARAFAC) and structural equation modeling (SEM) was employed in characterizing fingerprints and fractions of DOM from the topsoil samples. Five fluorescent components were extracted from DOM via EEM-PARAFAC, i.e., tryptophan-like (C1), microbial humic-like (C2), fulvic-like (C3 and C4), and humic-like (C5). The microbial humic-like was the primary component in the CRLD and HACY topsoils, while fulvic-like was the major component in the XYCY topsoil. Total organic carbon had substantial negative relationships with soil moisture (r = −0.885, p < 0.001), electrical conductivity (r = −0.746, p < 0.001) and exchangeable sodium percentage (ESP) (r = −0.695, p < 0.05), and displayed a high consistency among the different topsoils. Based on SEM, ESP had an impact on C1 in the CRLD, but primarily influenced C1 and C2 both in the XYCY and HACY, which in turn affected the degree of soil humification. EEM spectra combined with absolute PC coefficients is an effective approach to characterize soil DOM fractions not only in irrigation area but also in broad regions. [ABSTRACT FROM AUTHOR]

Submerged plants affect nitrogen cycling in aquatic ecosystems. However, whether and how submerged plants change nitrous oxide (N 2 O) production mechanism and emissions flux remains controversial. Current research primarily focuses on the feedback from N 2 O release to variation of substrate level and microbial communities. It is deficient in connecting the relative contribution of individual N 2 O production processes (i.e., the N 2 O partition). Here, we attempted to offer a comprehensive understanding of the N 2 O mitigation mechanism in aquatic ecosystems on the Changjiang River Delta according to stable isotopic techniques, metagenome-assembly genome analysis, and statistical analysis. We found that the submerged plant reduced 45 % of N 2 O emissions by slowing down the dissolved inorganic nitrogen conversion velocity to N 2 O in sediment (V f -[DIN] sed ). It was attributed to changing the N 2 O partition and suppressing the potential capacity of net N 2 O production (i.e., nor/nosZ). The dominated production processes showed a shift with increasing excess N 2 O. Meanwhile, distinct shift thresholds of planted and unplanted habitats reflected different mechanisms of stimulated N 2 O production. The hotspot zone of N 2 O production corresponded to high nor/nosZ and unsaturated oxygen (O 2 ) in unplanted habitat. In contrast, planted habitat hotspot has lower nor/nosZ and supersaturated O 2 . O 2 from photosynthesis critically impacted the activities of N 2 O producers and consumers. In summary, the presence of submerged plants is beneficial to mitigate N 2 O emissions from aquatic ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Non-Point Source Pollution (NPS) caused by polluted and untreated stormwater runoff discharging into water bodies has become a serious threat to the ecological environment. Green infrastructure and gray infrastructure are considered to be the main stormwater management measures, and the issue of their cost-effectiveness is a widespread concern for decision makers. Multi-objective optimization is one of the most reliable and commonly used approaches in solving cost-effectiveness issues. However, many studies optimized green and gray infrastructure under an invariant condition, and the additional benefits of green infrastructure were neglected. In this study, a simulation-optimization framework was developed by integrated Stormwater Management Model (SWMM) and Non-dominated Sorting Genetic Algorithm (NSGA-II) to optimize green and gray infrastructure for NPS control under future scenarios, and a realistic area of Sponge City in Nanchang, China, was used as a typical case. Different levels of additional benefits of green infrastructure were estimated in the optimizing process. The results demonstrated that green-gray infrastructure can produce a co-benefit if the green infrastructure have appropriate Value of Additional Benefits (VAB), otherwise, gray infrastructure will be a more cost-effectiveness measure. Moreover, gray infrastructure is more sensitive than green infrastructure and green-gray infrastructure under future scenarios. The findings of the study could help decision makers to develop suitable planning for NPS control based on investment cost and water quality objectives.

Metal-organic frameworks, an emerging class of porous material, have developed rapidly in recent years. In order to clarify the application of metal-organic frameworks in the field of environmental science, 1386 articles over the last 20 years were obtained from Scopus and analysed by the bibliometric method. And the collaboration between countries, institutions and authors and the co-occurrence of keywords were also conducted using VOSviewer. The results indicated that this area of research has entered a fast-developing stage. The number of articles published has grown from 7 articles in 1999 to 378 articles in 2018. The most productive country was China with 626 articles published. The most productive institution was the Chinese Academy of Sciences, and the most productive author was Jhung SH from Kyungpook National University of South Korea. Although metal-organic frameworks have been widely used in adsorption and catalytic degradation of pollutants from the environment, the removal mechanism of pollutants by MOFs, the stability improvement and the cost reduction of metal-organic frameworks are still the main challenges for their practical applications.

Elimination of black-stinking water contamination has been listed as an urgent task in the Water pollution prevention action plan promulgated by State Council of China. However, the key blackening and stinking pollutants and their sources are still unclear. In this study, water quality of a black-stinking urban river in Beijing, Dongsha River, was evaluated firstly; then the distribution of the blackening and stinking pollutants was investigated, and the key pollutants and their potential sources were identified; and finally, the health risk of those pollutants was assessed. The results showed that NH 3 N, total phosphorus, dissolved oxygen and chemical oxygen demand ranged from 1.3 to 5.3 mg/L, 0.7-3.0 mg/L, 1.0-3.2 mg/L and 29-104 mg/L, respectively. The value of TP-based trophic level index indicated that Dongsha River reached severe eutrophication level; the maximum value of chroma and odor level reached 32 and 4, respectively. The main dissolved organic compounds included aromatic protein II, soluble microbiological metabolites, fulvic acids and humic acids. The blackening pollutants Fe, Mn, Cu and S 2- were extensively detected, with significantly spatial differences along the river. Dimethyl sulfide, β-ionone, 2-methylisoborneol and geosmin were identified to be the stinking pollutants. Their concentrations covered wide ranges, and even the lowest concentration value was thousands of times higher than its olfactory threshold. Correlation analysis indicated that in the overlaying water S 2- was the key blackening pollutant, while β-ionone and geosmin were the key stinking pollutants. Principal components analysis combining with the site survey revealed their potential sources. S 2- was mainly associated with the decomposition of endogenous sulfur-containing organics; β-ionone might be generated by the endogenous β-carotene bio-conversion and the exogenous discharges, while geosmin might originate from the endogenous humus bio-conversion and anthropic wastes. Furthermore, multi-metals in the sediment posed health risks to children, while dimethyl sulfide had non-cancer health risk for adults and children., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The chemical industry is a major source of various pollution accidents. Improving the management level of risk sources for pollution accidents has become an urgent demand for most industrialized countries. In pollution accidents, the released chemicals harm the receptors to some extent depending on their sensitivity or susceptibility. Therefore, identifying the potential risk sources from such a large number of chemical enterprises has become pressingly urgent. Based on the simulation of the whole accident process, a novel and expandable identification method for risk sources causing water pollution accidents is presented. The newly developed approach, by analyzing and stimulating the whole process of a pollution accident between sources and receptors, can be applied to identify risk sources, especially on the nationwide scale. Three major types of losses, such as social, economic and ecological losses, were normalized, analyzed and used for overall consequence modeling. A specific case study area, located in a chemical industry park (CIP) along the Yangtze River in Jiangsu Province, China, was selected to test the potential of the identification method. The results showed that there were four risk sources for pollution accidents in this CIP. Aniline leakage in the HS Chemical Plant would lead to the most serious impact on the surrounding water environment. This potential accident would severely damage the ecosystem up to 3.8 km downstream of Yangtze River, and lead to pollution over a distance stretching to 73.7 km downstream. The proposed method is easily extended to the nationwide identification of potential risk sources.