Sixteen types of polycyclic aromatic hydrocarbons (PAHs) were included in the priority control pollutants listed by the U.S. Environmental Protection Agency (US EPA). Herein, the emission rates and emission sources of these 16 PAHs in Taiyuan city were investigated. Results showed that the overall emission amount of the 16 PAHs in the year of 2010 in Taiyuan was 332.10t, in which 35.11t was identified as carcinogenic PAHs. Most of the PAHs were generated from the combustion of household coal and coke-production coal, accounting for 65% of the total emission amount. Among the emissions of 16 PAHs, less-ring PAHs were the majority (81%) while the carcinogenic PAHs only accounted for 10.6%. For the different districts (10 in total) in Taiyuan, the PAHs emitted from Qingxu were 87t/a, greatly more than that from Gujiao (54t/a), Jinyuan (44t/a), and Jiancaoping (40t/a). In general, there were a negative correlation between per capita income and per GDP emissions of PAHs (R2=0.727), and a positive correlation between the rural population and total PAHs emissions (R2=0.813). It was concluded that the heavy PAHs emission in Taiyuan was attributed to excessive combustion of coal for the household and industry and unique energy structure and special population in the countryside.

Levels, spatial and temporal trends of 16 polycyclic aromatic hydrocarbons (PAHs) in oyster Crassostrea rivularis along the Hainan Island coast were investigated from 2009 to 2014. Results showed that the total concentrations of PAHs in oysters ranged from 289 to 2426ng/g with an average of 856.7ng/g on a dry weight basis. The PAHs levels from Hainan Island coast fell within moderate levels compared with those from other coastal areas in the world. The average concentrations of PAHs exhibited definite spatial differences and decreased in the order : Basuo Harbor> Yulin Harbor> Maniao Harbor>Dongzhai Harbor. Based on Mann–Kendall test, only Basuo Harbor showed a significant increasing trend (P<0.05). The composition of PAHs was characterized by 2~3rings of PAHs (ranging from 62.3%~92.5%). PAHs may originate mainly from petroleum and combustion of oil. Risk assessment suggested that the cancer risks in oysters from Basuo Habor exceeded the maximum acceptable risk (10-5), but did not reach the serious cancer risk level (10-4), while the cancer risks in other sites were acceptable. Further assessment suggested that daily intake of edible oyster tissue from Basuo Habor and other areas of Hainan Island should not exceed 56g and 67g, respectively.

通过对畜禽粪便年排放量的估算方法和畜禽粪便排泄参数的确定,估算了我国畜禽养殖业粪便产生量并对由此产生的环境效应进行了评价.结果表明,2003年我国畜禽养殖业共产生31.90亿t粪便,是当年工业产生固体废物的3.2倍;畜禽粪便及其中的氮、磷纯养分平均耕地负荷分别为24t/hm2,N107kg/hm2和P29kg/hm2.部分地区的畜禽养殖业已经对当地环境构成了污染.

A quantitative analysis of the major factors influencing the CO2 emissions from final energy consumption in Shanghai based on the Log-Mean Divisia Index (LMDI) method was presented. Besides the CO2 emissions from industrial energy consumption, the emissions from urban household energy use were also considered in the analysis. The major factors influencing the CO2 emissions including energy intensity, energy and industrial structure, economic growth, and urban population were thus identified and adopted as the parameters for the LMDI method. The results show that the actual CO2 emissions in Shanghai increased 29.49 million ton from 2005 to 2009. If no reduction approaches were employed, the incensement of the emissions induced by the economic and population growth would be about 2.5 times of the actual value in Shanghai. The decline in energy intensity, energy structure adjustment, and industrial structure adjustment were the major determinants for the CO2 emissions reduction, and the contribution rates of the three factors were -98%, -50%, and -22%, respectively. Comparing with the period of 2000~2005, energy intensity decline and energy structure adjustment as the driving forces of CO2 emissions reduction weakened. At the same time, the industrial structure adjustment began to benefit the CO2 emissions reduction whereas the contribution rate was still small. The increasing per capita urban household energy use with the population growth was the major factor on the rise of CO2 emissions, and the contribution rate increased gradually.

In this study, activated sludge samples were collected from 3municipal wastewater treatment plants (WWTP) and the performance and impacting factors of sulfides adsorption onto the activated sludge were investigated. The impacting factors include sulfides concentration, temperature, pH and other anions. Adsorption isotherm of sulfide onto the activated sludge can be well described by Langmuir equation. The maximum sulfide adsorption capacity was 15~27mg/g-dry sludge. At the temperatures ranging from 5to 35℃, adsorption capacity increased by the rise in temperature and this implies the sulfides adsorption was an endothermic process. The pH value had little effect on the adsorption capacity from 2to 7. But the sulfides adsorption capacity decreased significantly when pH was lower than 2. Sulfides were adsorbed by activated sludge as anions (HS- and S2-) and it was a chemical adsorption process. Cl- ranging from 0 to 25mg/L or SO2- 4 ranging from 0 to 12mg/L did not affect the sulfides adsorption capacity.

The mechanism of DON removal in the secondary effluent by ozonation and adsorption was investigated in this study. The water quality parameters, such as DON, DOC, NH4+-N, UV254 and pH etc, were determined. The variation in DON, DOC andUV254 in ozonation and adsorption tests measured, and the molecular weight distribution, hydrophilicity and hydrophobicity of the DON were then analyzed. The changes of DON in the secondary effluent were characterized using three-dimensional fluorescence spectroscopy. The results showed the removal of DON, DOC andUV254 were about 33.9%, 21.2% and 66.7%, respectively, at ozonation test and the dosage of ozone was 8mg/L. The removal of DON, DOC and UV254 were about 43.4%, 27.6% and 92.2% at the activated carbon dosage of 2.0g/L. By the combination of ozonation and adsorption the removal of DON was approximately 83.3% and 81.5%. Ozonation and acitivated carbon adsorption had opposite effects on the molecular distribution of DON. The proportions of smaller (20 000) ones were decreased by the former and increased by the later. Both treatment could increased the proportion of hydrophilic DON, and decreased them of hydrophobic and transitional DON. 3DEEM revealed that the variation of DON in ozonation and adsorption tests depended intimately on tryptophan protein-like and aromatic protein-like substances, and fulvic acid-like respectively.

The heat balance equation of Regenerative Thermal Oxidizer (RTO) was established according to actual operating condition of a painting workshop. The no-load and full-load operation data of RTO was calculated, and the relationship between furnace temperature and concentration of Volatile Organic Compounds (VOCs) was verified. On this basis, the influence of four key parameters of exhaust air volume, zeolite runner concentration ratio, heat exchanger heat utilization rate and VOCs concentration on natural gas consumption were discussed. The results show that the furnace temperature increased by about 21℃ for each 1000mg/Nm³ growth in the incoming VOCs concentration. The smaller exhaust air volume made the higher zeolite rotor concentration multiplier and heat exchanger thermal utilization rate, and thus resulted in higher VOCs concentration in the RTO. This results could reduce natural gas consumption. The heat balance equation was established in this paper, combined with the considerations in engineering application of RTO. When painting was being dryed, the minimum exhaust air volume of painting workshop was establed on the basis of 3 times/h. The concentration multiplier of zeolite rotor was set to 10~14times, and the heat exchanger with heat utilization rate above 0.7 was selected, which could significantly reduce the natural gas consumption, and ensuring the safe operation of RTO.

Cement-based solidification/stabilization (S/S) with DTCR (dithiocarbamate) as an additive was used to solidify and stabilize sediment containing heavy metals. The optimum ratios of cement and DTCR were determined by testing the compressive strength of the whole solidified body and leaching toxicity of granular solidified body (particle size￡9.5mm). And the effect of S/S was assessed though the leaching toxicity test of granular solidified body and whole solidified body in the acidic environment (pH 3). The mechanism of S/S was analyzed by X-ray diffraction (XRD) and envrionmental scanning electron microscope (ESEM). The optimal proportion of cement and DTCR was 50% and 2% (w/w, dry basis), respectively. Under optimum conditions, the 7d compressive strength of the solidified body was up to 1.03 MPa and leaching concentrations of Cu, Zn, Pb and Cd in granular solidified body were 0.105, 4.65, 0.232, 0.123 mg/L, respectively, which could meet the requirements of the security landfill. The leaching effect in the acidic environment (pH 3) demonstrated that cement-based S/S added DTCR was better than cement-based S/S only. XRD and ESEM analysis revealed that Ca(OH)2, Hydrate Calcium Silicate (C-S-H) and Ettringite (AFt) as hydration products would be formed in hydration reaction which wrapped up heavy metals and form a solidified body with certain strength.

The objective of this review was to summarize the microplastics aging characteristics and mechanisms, and further the adsorption behaviors of pollutants on microplastics were reviewed. The main conclusions were drawn as follows: (1) The microplastic surface would become rougher after long-term aging, accompanying with some pieces flaking and falling off, which resulted in increasing of specific surface area. Meanwhile, the formation of oxygen functional groups such as hydroxyl, carboxyl. was found after exposure to several factors in environments such as oxygen and sunlight. In addition, the long molecular chains of the microplastics were broken due to aging, which altered their crystallinity. (2) Microplastic aging processes could be found as follows: as for physical aspects, the molecular chain in polymers was destructed by the shear and tensile forces externally and thus the stable structure was destroyed. Photooxidation degradation was the main aging mechanism from the aspect of chemical reactions. On the biological level, the physical and chemical characteristics of microplastics such as roughness, surface charge and surface free energy facilitated the biofilm formation on the microplastics by colonizing microorganisms, which then affected the migration behaviors of microplastics in environments. (3) The adsorption capacity of microplastics to pollutants(heavy metals and organic pollutants) could be enhanced after aging, which were mainly affected by van der Waals' force, electrostatic action, complexation, hydrophobic action and hydrogen bond. In the future, we should pay more attention to the study of the aging characteristics of microplastics in complex environments and their interactions with various pollutants. Exploring the relationship between these pollutants quantitatively and using the models provides the theoretical basis of understanding the behavior and assessing the ecological risks of microplastics in environments scientifically and reasonably.

运用热水解、超声波和微波等3 种方法预处理污水剩余污泥,通过测定污泥pH 值、可溶性蛋白质、总糖和可溶解性化学需氧量(SCOD)等指标考察其对污泥破解效果的影响.结果表明,在各种预处理中,污泥pH 值变化不显著.污泥破解效果随处理强度的增加而增强.超声波
ED=2W/L,t =10min 条件时,污泥的破解效果最好,可溶解性蛋白质、总糖和SCOD 浓度分别为1013.6,512.6,4184 mg/L;SCOD/TCOD 值较原始污泥升高了41.73%.从实际应用和运行成本考虑,长时间而低强度的处理都能够达到较为理想的破解效果,即热处理(t=75min,T=45℃),超声波处理(t =10min,ED=0.5W/L),微波处理(t =300s, p =70W). 在能耗相同的条件下,破解效果为超声波>微波>热水解.

The effect of continuous discharge and adsorptive storage-intermittent discharge combined with SBA-15on toluene decomposition was investigated under ambient pressure and temperature. The results showed that adsorptive storage-intermittent discharge method exhibited higher toluene conversion, CO2 selectivity and better carbon balance compared to the former. The evolution of the intermediate products on the catalyst surfaces with time were also analysed by GC-MS in both methods. The results indicated that formaldehyde oxidation was the rate-determining step for toluene decomposition. Then, the activities of four different catalysts, SBA-15, Mn/SBA-15, Ag/SBA-15and AgMn/SBA-15were tested with dsorptive storage-intermittent discharge mode. AgMn/SBA-15catalyst exhibited the highest CO2 selectivity and the best carbon balance among the tested catalysts, which may be due to 2-heptene alcohol oxidation catalyzed by the addition of Ag and Mn.

With the aim at investigating the distribution of pollution in Xi′an city, a systematical sampling of street dust was carried out. Rock magnetic measurement showed the street dust had a high magnetic susceptibility and low frequency dependent susceptibility. Their obviously negative correlation indicatd that the magnetic enhancement mainly attribute to the human activity. Thermomagnetic analysis indicated that the samples affected by electricity generation station were dominated by magnetite, while samples influenced by several sources had maghemite, hematite and little amount of pure iron as their dominant magnetic minerals. Statistical analysis exhibited a great positive correlation between the magnetic susceptibility and elements like Pb and Ba which attribute to the traffic, pollution and elements like Cu and Cr which were resulted by metallurgic industry. Pollution in Xi′an city mainly attribute to the traffic pollution and metallurgic industry, and magnetic susceptibility could be used to reflect the intensity of pollution. Besides, magnetic susceptibility displayed a different correlation with different element in different districts. And this may indicate that the human activity that caused magnetic enhancement was different in each district in the city.

The microwave and centrifuge technologies were combined to release bound water and improve dewatering capability, which was carried out by measuring the Capillary Suction Time (CST), rheological parameters and water content, collecting sludge images to extract morphological features and analyze fractal dimension. The experimental results indicated that water content decreased with an appropriate increase of centrifugal speed and temperature. When microwave power was 1000 W, microwave temperature was 50℃, centrifugal speed was 2000 r/min and centrifugal time was 15 min, the water content of sludge reached the lowest value of 83.75%. The fractal dimension of sludge was in the range of 2.4-2.8 after the pretreatment of microwave. A model of dewatering characteristics was established by fitting dewatering capability parameters and water content, which would contribute to predicting and improving dewatering capability of sludge.

The concentrations of 7selected pharmaceuticals and personal care products (PPCPs) in the Huangpu River were determined by solid phase extraction and high liquid chromatography-electrospray tandem mass spectrometry (SPE-HPLC-MS/MS). The results showed that the developed analytical method obtained good recoveries (87~107%), relative standard deviation (<14%) and limit of quantification (0.1~1.1ng/L), satisfying the requirement to detect micropollutants in the surface water. By applying the method in Huangpu River, we found that compared to other reported studies, the contamination levels of target PPCPs were low in Huangpu River, with the concentrations varying from

Based on existing literature data, we analyzed the pollution characteristics of four-type antibiotics used commonly, including tetracyclines, sulfonamides, quinolones and macrolides, in 38 typical lakes, which are distributed in eastern plain lake region (31), Mengxin lake district (4), Erlong Lake, Qinghai Lake and Fuxian Lake. The results showed that the four-type antibiotics were ubiquitous in waterbody and sediments of these lakes, and the pollution concentrations decreased as follows:SAs (2147ng/L)> quinolones (QNs, 1458ng/L)> tetracyclines (TCs, 481 ng/L)> macrolides (MLs, 205 ng/L). The antibiotics in sediments exhibited vertical difference, with higher pollution concentration in surface sediment than that in deep sediments. The antibiotics concentrations varied among different lake regions, and in the eastern plain lake region showed higher contamination level. Compared with the inflow rivers, lakes, such as the Gonghu Bay in Taihu Lake and Qinghai Lake, generally showed relatively higher contamination levels, suggesting that lakes serve as a reservoir of antibiotics. Seasonal comparison in pollution levels in waterbody of lakes showed that the antibiotic concentrations in pring, summer and winter was significantly higher than that in the autumn. For example, Poyang Lake, Baiyangdian Lake and Erlong Lake' antibiotic pollution was higher in dry season (April) than in rainy season (August). However, antibiotics concentrations in lake sediments were comparable between different seasons, probably resulting from the migration of antibiotics in sediments.

13kinds of common water resources conservancy measures were classified into three (source, process and terminal) control systems. In addition the measures of each category were evaluated by the Analytic Hierarchy Process method as well as 13 factors of the technical suitability and economic feasibility of water conservancy measures. The results indicated that pollutants removal rate, effluent water quality, cost of construction, operation, and maintenance should be given priority in real world applications they had the higher weight value than other indices. Conservation tillage and ‘One biogas pond with improvements of washroom, kitchen and sty’ could be used as the preferred methods in source control. Moreover, land treatment technology was more suitable than other process control methods. External temperature and construction costs must be considered when selecting terminal control methods.

SWAT model was utilized to simulate the results of Best Management Practices (BMPs) for non-point source (NPS) pollution in Dangjiangkou Reservoir basin. Cost, change of cultivated land area and reduction of non-point source pollution load of each BMP as well as the pollution reduction was taken into consideration when conducting the management practices optimization in different slope-degree zones. Multiple attribute decision making based on information entropy was applied to optimizing BMPs. Crop residual cover, contour ploughing and no-tillage were suggested to be conducted in region with slope degree less than 5°. In the zone with slope degree from 5° to 15°, terrace was demonstrated to be the most effective practice. This research also stated that hedgerows was firstly suggested to conducted in 15°~25° zone, while crop residual cover was another prior practice in this area. Conversion of cropland to forest had superiority as the best management practice in >25° area. This research provided decision making support for BMPS for NPS pollution reduction in Danjiangkou Reservoir basin.

A continuous air pollution event occurred in the Yangtze River Delta during from December 1 to 9, 2013. The formation, characteristics and potential sources of this air pollution event were explored by using the aerosol products of MODIS and CALIPSO satellite, ground air quality, meteorological data and HYSPLIT backward trajectory model. The results showed that, the 8 typical cities of the Yangtze River Delta were dominated by the haze pollution during this event. Aerosol optical depth (AOD) increased significantly, air quality index (AQI) reached or was higher than the limit value of pollution, and it is mainly higher than the level of moderate pollution. During the event, the aerosol mainly exist in the level from the ground to 2km above, especially under 850m. Based on volume depolarization ratio and color ratio, the higher frequency of spherical aerosol than that of non-spherical aerosol and the higher frequency of large size aerosol particle than that of small aerosol particle indicated that the main aerosol type was "pollution" aerosol during the pollution event. Short distance transport of pollutants and static weather conditions with continuous low wind speed and no precipitation which made the pollutants difficult to disperse, led to the widespread, long-time and severe pollution event in the Yangtze River delta.

Triclosan (TCS), triclocarban (TCC), and bispenol A (BPA) are all proved to possess endocrine disrupting effects; however, little data are available on their neurotoxicity effects on zebrafish (Danio rerio) and the underlying molecular mechanisms. Herein, zebrafish transcriptomic data was obtained with the aid of RNA-Seq after exposure to the aforementioned three pollutants. By means of bioinformatics analysis, nine common positively differential expression genes (DEGs) were screened in the three exposure treatments. The GO functions and KEGG pathways of nine DEGs were mainly attributable to biological process, cellular component, and molecular function, in which the number and function were different with varying chemical exposure. Notably, most of the DEGs were found to be enriched in the nerve-related pathways, but their detailed pathways were different for three chemicals. The computation of node-correlation degree of PPI network showed that the hub genes enriched in neural pathways were different in the three treatments, which had rich and indirect interaction networks with neural marker genes. By integrating DEGs with GBM mutant gene of glioblastoma in the TCGA database, we confirmed that chemical exposure induced GBM risk, but the related occurrence pathway and regulatory signaling pathway were different. Therefore, the underlying neurotoxicity mechanisms induced by the three pollutants were disclosed at the molecular level.

Mathematical simulation technology (MST) has been widely applied in wastewater treatment, therefore, in order to systematically summarize these related technologies, this study reviewed the development of MST in sewage treatment system, and the application of activated sludge model (ASM) and machine learning (ML) in water quality prediction and parameter optimization; In addition, this paper mainly discussed the models of greenhouse gas emission in sewage treatment system, and the trade-off of multi-objective optimization model in sewage treatment system with the objectives of greenhouse gas emission (GHG), effluent quality (EQI) and operating cost (OCI). Furthermore, this paper also summarized the development of MST to achieve the energy self-sufficiency and resource recovery of sewage plant. The results from this study showed that MST can accurately predict the effluent quality, quickly optimize the process parameters, weigh the relationship among greenhouse gas emission, effluent quality and the operation cost, and improve the resource recovery efficiency. Overall, MST can effectively guide the operation optimization and management of sewage treatment process, and ultimately provide technical supports for the synergy of pollution reduction and carbon reduction in sewage treatment industry.

In order to study the gas-particle partitioning of polychlorinated biphenyls (PCBs) in ambient air of Xi’an City, China, both gas and particle phases samples were collected using an active air sampler on a weekly base during spring in 2012. The results showed that the total concentration (gas plus particle phases) of PCBs ranged from 62.05 to 454.18 pg/m3, with much higher concentration in gas phase than that in particle phase. The steep slope (-5193.24) obtained from Clausius-Clapeyron equation indicated that PCBs concentration in Xi’an City was mainly influenced by the evaporation from adjacent land surface. Gas-particle partitioning coefficients (KP) of PCBs were well correlated with the sub-cooled vapor pressure (PoL) however, the slopes (-0.46~-0.37) obtained from linear regression between logKP and logPoL were shallower than the theoretical value of -1 at equilibrium condition. The results indicated that partitioning of PCBs between the gas and particle phases in the air in Xi’an City was under non-equilibrium condition. The particle bound fraction (φ) and KP value were estimated using the Junge-Pankow adsorption model and Harner-Bidleman absorption model, the result showed that gas-particle partitioning of PCBs was well simulated by both models, however, both models tended to overestimate the values of φ and KP compared with those obtained from field measurement.

In order to study the pattern of regional transport of PM2.5 and its chemical components, we developed a transport matrix of PM2.5 and its chemical components from the 31provinces (source) to 333cities (receptor) by applying the Particulate Source Apportionment Technology (PSAT) of CAMx model. The regional contribution of ambient PM2.5 and its key components, such as primary PM, sulfate, nitrate, and ammonium, are identified and quantified at region, province, and city level. The results indicate significant contribution of regional transport to ambient PM2.5 pollution in key regions and typical cities in Jing-Jin-Ji area. 22%, 37%, 28%, and 14% of ambient PM2.5in Jin-Jing-Ji, Yangtze River Delta, Pearl River Delta, Chengdu-Chongqing area, respectively, is contributed by emissions from outside region. Regional transport of pollutants contributes to more than 45% of annual average PM2.5 concentration in some provinces such as Hainan, Shanghai, Jiangsu, Zhejiang, Jilin and Jiangxi, and contributes to 37%, 42% and 33% of annual average PM2.5 concentration in Beijing, Tianjin, and Shijiazhuang City.

Soil ecotoxicological effects of toluene, ethylbenzene and xylene (TEX) were investigated using earthworm (Eisenia fetida) and wheat (Triticum aestivum L.). The results showed that there were significantly positive correlations between the lethal or inhibitory effects on Eisenia fetida and Triticum aestivum L. and the tested concentration of the three pollutants. The 24h LC50 values of TEX toxic to Eisenia fetida were 583.6, 346.8 and 192.4mg/kg, and the 48h LC50 values were 454.3, 167.1 and 127.2mg/kg, respectively. The IC10 values based on the toxicity of TEX to shoot elongation of Triticum aestivum L. were 342.2, 195.4 and 45.9mg/kg, and the IC10 values based on the toxicity of TEX to root elongation were 206.7, 134.5 and 26.3mg/kg, respectively. Although both the root and shoot elongation of wheat could indicate the pollution extent of TEX in soil, root elongation was more sensitive than shoot elongation under the pressure of the three pollutants, and there was a significantly positive correlation between these two indexes.

Based on Illumina MiSeq high-throughput sequencing technology, the structure, abundance and correlation of the microbial community at different temperatures were discussed in the A²O process activated sludge under the plateau habitat. Combined with the role of the main functional proteins, functional genes, enzymes and their abundance in the metabolic pathways of carbon, nitrogen, phosphorus, sulfur and other pollutants during the decomposition, adsorption and transformation of pollutants, the microbial mechanism of A²O process for sewage treatment in plateau area was analyzed from the perspective of biochemistry and molecular level. The results showed that the dominant bacterial Phylum were Proteobacteria, Bacteroidetes, Actinobacteria, Firmicutes and Chloroflexi, and the dominant bacterial genus norank_f_AKYH767, norank_f_Saprospiraceae, Ottowia, unclassified_f_Burkholderiaceae, IMCC26207, and Novosphingobium. The optimum temperature for pollutant removal and microbial community was 15℃, and the optimum temperature for COG, metabolic pathway, gene and enzyme activity of microbial community was 20℃. The main functional proteins were general function prediction only, amino acid transport and metabolism, transcription. The main metabolic pathways were ABC transporters, two-component system, purine metabolism, ribosome and pyrimidine metabolism. The main functional gene products (enzymes) were enoyl-CoA hydratase, acetyl-CoA C-acetyltransferase, aldehyde dehydrogenase (NAD+), thiosulfate and exopolyphosphatase.

The toxicity effects of single exposure of polylactic acid (PLA) microplastics, as well as their combined exposure with other environmental pollutants were reviewed. Moreover, the toxicity mechanisms of PLA microplastics on organisms was further summarized. The ingestion of PLA microplastics can affect the feeding, growth, survival, reproduction and motor behavior of organisms. The combined contamination of PLA microplastics with organics and heavy metals has certain potential risks to organisms. PLA microplastics mainly damage organisms through the toxicity mechanisms of mechanical damage, oxidative stress, nerve damage and immune damage. Future studies are needed to explore the toxic effects of aged or degraded PLA microplastics, the toxicity effects and mechanisms of combined exposure to terrestrial organisms, and their impacts on global ecosystems and biogeochemical cycles. This review could provide ideas for the environmental and ecological risk assessment of PLA microplastics in the future.

As one of the most commonly used nanoparticles, nano zero valent iron (nZVI) had been extensively studied in the removal of pollutants from environmental water. This review systematically and comprehensively summarized the related progress of nZVI, introduced various aspects of nZVI and then guided its development direction. Among them, the research contents mainly included preparation method, modification method, mechanism of action and catalytic mechanism for removing different pollutants in water, application in site research, and mechanism of toxicity. In this paper, it was found that there were still problems such as lack of comprehensive evaluation methods, limited application, and asynchronous research on nano zero valent iron. The future development of nZVI should have evaluation methods that consider reactivity, stability, mobility, and toxicity, to avoid the time difference of the same modified material in different research directions, so that the application of nZVI can be better applied to field research, and promote the application of nZVI in the field.

The biochar has been regarded as an excellent catalyst carrier with promising application prospects in the area of environmental pollutant degradation and organic synthesis, due to its environmental friendliness and rich raw materials. However, the intrinsic catalytic capability of the biochar cannot satisfy the demand in some specific applications. To address this challenge and enhance the catalytic capability of the biochar, many activation methods were involved, including the acid activation, alkaline activation, gas activation, plasma activation and metal impregnated activation methods. In this study, the effects of different activation methods on the pore distribution, specific area, active group, density of active sites, and catalytic capability of the biochar were compared. Additionally, applications of the biochar activated by different methods were discussed. This paper could provide references for the design of customizing biochar and its future applications.

This review summarized the literature data, including bioaccumulation of 19 kinds of per- and polyfluoroalkyl compounds (PFAS) by 36 plants. Exposure, transport, and bioaccumulation feature data are summarized and interpreted; the mechanism of migration and accumulation of PFAS from environmental media to plant tissues was systematically elucidated; effects of PFAS molecular structure (such as perfluorocarbon chain length and head functional group), plant physiological characteristics, and environmental factors on the bioaccumulation process were discussed. In addition, future studies of phytoremediation and combined remediation of PFAS contaminated sites were prospected. The information can be used to manage and evaluate PFAS-contaminated sites, formulate phytoremediation plans, and assess ecological and health risk of PFAS contaminated sites.

To effectively assess the potential ecological health risks of organophosphate esters (OPEs), this study gave an overview of the global OPE pollution in water and sediment with a focus on their toxic effects on aquatic organisms. The potential toxicity mechanisms were also analyzed in different kinds of biota including plankton, nekton and benthos, and the future research directions and scientific issues in aquatic environmental studies were finally prospected. This study would be helpful for effective assessment of ecological effects and health risks of OPEs. It would also positively promote the food safety monitoring and ecotoxicology research of OPEs, and provide reference for regulating their green applications.

A remote sensing based ecological index (RSEI) was developed specially for monitoring and assessing regional ecological changes. The index combined four indicators from existing remote-sensing indices/components to represent greenness, dryness, wetness and heat, which were the important ecological indicators frequently used in assessing regional ecology. Instead of a weighted addition of the four indicators, the principal component analysis (PCA) was utilized to compress the four indicators into one in order to assess overall regional ecological status. The RSEI was then constructed using the first component (PC1). The application of RSEI in Hetian area of County Changting in Fujian Province, China, showed that the RSEI could quantitatively reveal regional ecological changes during the period from 1988 to 2010. The RSEI values could be well compared with the commonly-used ecological index (EI). Nevertheless, besides working as a quantitative indicator, the RSEI had more functions than the EI, such as detecting, simulating and predicting spatiotemporal changes of regional ecological quality.

In this paper, the adsorption properties, mechanisms, influencing factors, advantages and potential problems of different adsorbents (activated carbon, resin, mineral materials, molecularly imprinted polymers, bio-based materials, etc.) for PFAS removal were summarized. Adsorbents with similar pore size to PFAS molecules, and with opposite surface charge had higher adsorption capacity to PFAS. Lower pH and higher temperature are more favorable for PFAS adsorption, and coexisting organic matter will compete with PFAS on adsorption. The adsorption performance of the adsorbent to PFAS was positively correlated with its chain length, and the adsorption capacity of the adsorbent to PFAS containing sulfonic group was higher than that of PFAS with carboxylic group at the same chain length. The main adsorption mechanisms include electrostatic attraction, hydrophobic interaction, ion exchange, ligand exchange, etc. The reasonable regeneration and disposal of adsorbents was a common problem in practical engineering applications, such as poor regeneration effect of chemical regeneration and biological regeneration, high energy consumption of thermal regeneration, easy to cause secondary pollution by solvent regeneration or landfill treatment. By reviewing the research progress of adsorption removal materials and technologies for PFAS from water, the advantages and disadvantages of different technologies are systematically expounded, and the research direction of adsorption removal technology is prospected, which could provide reference for PFAS pollution control in water.

Microplastics, as a novel type of plastic contaminant, widely exist in the global marine environment, and have become a hot environmental issue in the international community. Poorly managed waste is an important source of marine pollution. In this paper, the pollution situation of plastic waste and microplastics in the world and the sources of micro-plastics are briefly analyzed. And the latest progress in the revision of annexes to plastic waste covered by the Basel Convention was discussed. Meanwhile, the size, abundance, distribution and sources of microplastics in coastal, estuary and inland waters of China were summarized and analyzed. It was proposed that the management system of plastics and microplastics in China should be established and improved in the future, research and supervision on the discharge of plastics and microplastics from key industries into the ocean should be strengthened, a risk assessment system for the impact of microplastics on marine ecosystems should be established, publicity and education should be strengthened, and actively participate in the negotiations on the implementation of international environmental conventions to promote global governance.

Changes in the UV-visible and fluorescence characteristics of DOM from the co-composting process of municipal sludge with two types of biochars were discussed. The results showed the aromaticity and humification of DOM from the co-composting with biochars significantly increased compared with control, which indicated in favor of improving the maturity of compost. The treatment with biochar from peanut shell showed the highest maturity, followed by wheat straw biochar. After 21days, compost treated with biochar from peanut shell reached its maximum maturity, while that treated with biochar from wheat straw continued to increase over the whole time. Meanwhile, the DOM from the compost with or without treatment was found to be autochthonous, FI>0.7, BIX>0.8, mainly attributed to the microbial decomposition of compost. Thus, the spectral characteristics of DOM are capable of assessing the degree of maturity of compost during the co-composting process with biochars from different source.

The growing annual disposal volume of municipal solid waste (MSW) is causing serious environmental problem worldwide. Different components in MSW have their own appropriate treatment and utilization techniques, thus effective MSW classification is significantly important. While current classification methods in China is primarily artificial classification, which have a lot of disadvantages such as low efficiency, high cost and low accuracy. These bottlenecks could be excellently solved by intelligent and automatic classification technologies. The recent distribution feature and growing trend of MSW in China's representative cities were briefly introduced, and the existing intelligent MSW classification technologies in six categories of principles were analyzed. These categories included density, electricity, magnetism, image, acoustic and spectrum. The practical applications of intelligent MSW classification technologies were also introduced. Finally, the threats and opportunities faced with intelligent MSW classification technologies were analyzed.

Based on the multistage anoxic-oxic (MAO) process and the theory of denitrifying phosphorus removal, a noval MAO process (DPR-MAO) with ability of denitrifying phosphorus removal was designed. In this study, the nitrogen and phosphorus removal performance and the microbial community characteristics of each reaction tank were investigated. During period of stable operation, the average COD, TN, NH₄⁺-N and TP concentration in effluent were 7.07, 9.04, 0.34 and 0.49mg/L, respectively. Meanwhile, the average removal efficiecny of COD, TN, NH₄⁺-N and TP were 98%, 87%, 99% and 93%, respectively. The effluent quality of DPR-MAO process could meet the first A level of the "Discharge standard of pollutants for municipal wastewater treatment plant” (GB 18918~2002). High-throughput sequencing results suggested that Proteobacteria, Bacteroidetes and Chloroflexi were the dominant phyla in each reaction tank, accounting for 61.85% ~ 75.58%、16.39% ~ 22.60% and 1.52% ~ 4.76% of the total phyla, respectively. Further analysis at the genus level found that Thiothrix, Comamonas, Candidatus Accumulibacter and Pseudomonas were the dominant genus for denitrifying phosphorus removal. The DPR-MAO process realized the enrichment of denitrifying phosphorus accumulating organisms and the efficient removal of nitrogen and phosphorus from wastewater.

Iron ammonia oxidation, also known as Fe(III) reduction coupling with anaerobic ammonia oxidation technology has the advantages of low sludge yield, no need for organic carbon, and tolerance to heavy metals. In this review, the potential mechanisms of Feammox, iron reduction pathways and functional microorganisms are described. And key influencing factors including pH, temperature, source of Fe(Ⅲ), organic matter as well as nitrates and nitrites are discussed. From the perspective of coupling Feammox technology with other nitrogen removal processes, the latest development trend of Feammox technology in wastewater treatment applications is reviewed, and the future development is prospected. An overview of the latest developments in the Feammox process provides valuable information for further process optimization and contributes to better nitrogen removal performance in future practical applications.

Anaerobic digestion (AD) offers an attractive method to reduce the negative impact of organic waste existing in the environment such as stalk, animal manure and municipal sludge. The biogas, digestate and slurry generated have great application value in energy, agriculture, environmental protection and other fields. However, AD has some problems such as the lag phase, the inhibition effect caused by ammonia nitrogen, VFA and so on, and low methane content in biogas. Hydrochar is the solid product of hydrothermal carbonization of biomass which is converted to porous multi-functional carbon-based material with the presence of subcritical water in the sealed equipment under the effect of heat and pressure. The potential benefits and applications of hydrochar have received significant attention with complex pore structures and high density of oxygen-containing functional groups. There is a comprehensive strengthening effect on AD including shortening the lag phase, alleviating the inhibition, favoring electron transfer between microbes, and enhancing the CH₄ production with the addition of hydrochar. Specifically, it was brought together recent advances made in the area through a systematic and critical review of the characteristics, modification, and strengthening effect on AD of hydrochar. The potential and limitations involved in the hydrochar application on AD were pointed out with suggestions for further research to exploit the great potential of AD on treating agricultural wastes.

To clarify the ecosystem health status of urban mangroves in Guangdong-Hong Kong-Macao Greater Bay Area (GBA), an indicator system for ecosystem health assessment of urban mangroves was developed based on PSR (Press-State-Response) model and analytic hierarchy process in this study. The indicator system was conducted on four typical urban mangroves in GBA: Mai Po in Hong Kong, Futian in Shenzhen, Nansha in Guangzhou, and Qi’ao island in Zhuhai. The health problems were identified and management strategies were put forward. The results showed that: The ecosystem health index (EHI) of mangroves were Qi’ao island (3.05, health)>Mai Po (3.03, health)>Nansha (2.54, sub-health)>Futian (2.13, sub-health). As for the press indicators, the natural pressure sources for mangroves in Mai Po and Futian were pests harm and biological invasion, while the artificial pressure came from the increasing population, the rapidly developed economy, and municipal wastewater discharge. In addition, the mangroves in Futian were suffering from the discharge of industrial waste. In terms of the state indicators, four urban mangroves were all suffering from seawater eutrophication. Organic and heavy metals seriously polluted the mangroves in Nansha and Qi'ao Island. The biodiversity of mangrove plants (except for Nansha) and macrobenthos was low, but birds' biodiversity was relatively high. For the response indicators, the mangroves in Futian and Nansha hold low ecological service functions due to their small areas, and the management level of mangroves in Nansha was insufficient. The leading health problems of urban mangroves in GBA include two aspects: firstly, common issues, including pests harm and biological invasion caused by ecological imbalance, environmental pollution caused by external pollution, decrease in biodiversity caused by habitat destruction. Secondly, personality issues, including the differences in the characteristics and management levels of mangroves. Considering the health problems mentioned above, suggestions are proposed: effectively monitor and promote ecological restoration based on natural laws to alleviate ecological imbalance, take source control as the foundation and improve environmental quality as a whole, focus on the protection of biodiversity and improve the stability of mangrove ecosystem, in accordance with local conditions and give full play to the economic, social and ecological benefits of urban mangrove.

The impact of meteorology variation on PM_2.5 concentration in autumn and winter of 2018~2019 in China was quantified with WRF-CMAQ model. Compared with the previous autumn and winter, the worse meteorological conditions in 2018~2019 led to 5.55% increase of average PM_2.5 concentration national wide. The meteorological condition of 24 provinces out of 31 got worse from the PM_2.5 pollution point of view. The PM_2.5 concentration in Beijing rose by 3.66% due to worse meteorological condition. Among the three key regions, the "2+26" cities was the most unfavorable in terms of the meteorological conditions, which led to the increase of PM_2.5 concentration by 9.4% compared with last year, followed by Fenwei plain (8.3%) and Yangtze River Delta(1.1%). The meteorological conditions of "2+26" cities and Fenwei plain were not favorable in November, January and February, and favorable in October and March. For Yangtze River Delta, the unfavorable meteorological condition took place in October, November and March, while the favorable months were December, January and February. Efforts of abating emissions somehow offset the adverse effects from the worse weather condition in Fenwei plain. The worse meteorological condition dominated the change of PM_2.5 concentration in "2+26" cities, while the greater emission reduction and small meteorological condition variation led to drop of PM_2.5 concentration in YRD.

In order to promote the industrial-scale application of anaerobic co-digestion (AcoD) of sewage excess sludge (ES) with food waste (FW) and enhance its energy recovery efficiency, this study systematically summarized the mechanisms of AcoD process, the distribution of co-digestive products and the factors that may affect the AcoD performance, the important research advances of direct interspecific electron transfer in AcoD were then reviewed, followed by the novel perspectives of AcoD process were proposed, such as developing efficient and economic methods for feedstock pretreatment, characterizing substrates degradation, understanding metabolic regulation by omics technologies, mitigating the effect of potential inhibitors in the AcoD systems, and in-situ coupling with other wastes, to improve digestion performance and stability. This study may provide a guidance and reference for efficient energy recovery of urban organic solid wastes.