Spatial and temporal distribution characteristics of Fog days and haze days and connecting factors have been analysed by applying meteorological data from 42 surface weather stations in the Yangtze River Delta region from 1960 to 2012. Results show that:In terms of spatial distribution, the major fog values are distributed in east coastal area of Yancheng city, Huangshan mountain and east coastal area of Zhejiang, while the major haze values are distributed in Nanjing, Hangzhou, Hefei, Quzhou, together with other surrounding cities. In terms of temporal distribution, the annual fog days in large cities has increased since the 1960s but discreased in 1980s; the fog days at small cities has a time lag compared to the evolution at the large cities. Monthly variation of fog days for the large cities appeared with high frequency in winter and spring while less and least in autumn and summer, Monthly variation of fog days for the small cities displayed bimodal trend, with more fog days in spring and winter. Average number of haze days at large cities and small cities depicted a increasing trend, and the differences in the number of haze days for large and small cities had been widening after 1990s. The rising temperature caused by regional climate change and urbanization and the high aerosol abundance caused by heavy air pollution led to the major reason of the different variation characteristics of haze days and fog days in Yangtze River Delta region. However, due to the complicated interaction between each influencing factors, intensive investigation is still required for further study.

One year measurements of Mie scatter lidar at Beijing were performed between June 2009 and May 2010. First of all, the data were split into four seasons:Spring(March-May), Summer(June-August), Autumn(September-November), and Winter(December-February). Next, the data were quality controlled. At last, Change of daily mean values of aerosol backscattering coefficient, extinction coefficient, AOT, and atmospheric boundary layer(ABL) were analyzed. At the same time, the vertical profiles of the aerosol backscattering coefficient, extinction coefficient, their variability during each season, the annual average, and the statistics were calculated, the characteristics of the AOT and the planetary boundary layer were also presented. The analyses revealed that, the average daily characteristics of the aerosol extinction coefficient and backscattering coefficient were the same, and the extinction coefficient was about 10 times of the backscattering coefficient. The seasonal mean aerosol backscatter and the extinction profiles did not exhibit significant seasonal differences in structural characteristics. The maximum decrement of the backscatter coefficients and extinction coefficient occurs within 1km above ground. The vertically averaged(between 0.15~3.0km) backscatter and extinction coefficients had the highest averages value(31.2Mm^-1·sr^-1 and 517.0Mm^-1, respectively) in summer, which reflects the stronger convection during summer. The winter had the lowest aerosol backscatter and extinction coefficients. For winter and spring seasons, 700m was the height where these two quantities showed different trend. Above 700m, the backscattering coefficient and extinction coefficient in spring were higher than those in winter. The fluctuations of daily average AOT and ABL height were significant, and the maximum amplitudes appeared in spring. On average, the residual layer and PBL were the highest in spring(3450 m and 970 m respectively), and the lowest in winter(2970 m and 604 m respectively). In spring and summer, the fluctuation of AOT varied greatly, but the fluctuation in autumn and winter was relatively mild. The average AOT in spring, summer, autumn, and winter is 0.689, 0.699, 0.571, and 0.647 respectively.

In order to investigate the properties and variation of dust aerosol transportation, the weather condition and pollutant characteristic that influenced air quality of Shijiazhuang on April 15^th, 2015 were analyzed. The HYSPLIT-4model was applied to analyze the back trajectories of dust aerosols. The ground-based micro-pulse Lidar and CE-318sun photometer measurements were used to study the vertical distribution of dust particles and its optical properties variation. In addition, it was compared with another case with strong wind but non dust aerosol deposition. The dust deposition effect on extinction coefficient was discussed. And the contribution of dust deposition to surface PM₁₀ concentration was evaluated. The results indicated that the major factor of rapid increase PM₁₀ concentration in Shijiazhuang was due to the long-distance transportation and deposition of dust particles from Mongolia by the direction of northwest. Dust deposition had an important contribution to both extinction coefficient and PM₁₀ concentration. The rapid dust aerosol disposition was consistent with cold front movement and cold air sinking over Shijiazhuang region. The whole process of dust transportation and disposition had been monitored by the micro-pulse Lidar. It was found that the dust particles mainly distributed on the height of 1500m to 3000m before sinking, where the extinction coefficient increased with the altitude. The process from dust transportation to deposition lasted long time, which could be regarded as one strong alarm signal for dust pollution. When the dust particles arrived over Shijiazhuang region, the aerosol optical depth, turbidity, and particle size showed larger values and the visibility decreased exponentially with the aerosol optical depth.

The temporal and spatial variations of the concentration of PM_2.5 from the year 1850 to 1980 and 1980 to 2010, as well as the contributions of anthropogenic and natural aerosols to these variations were simulated in this work, using an aerosol-climate coupled model BCC_AGCM2.0.1_CUACE/Aero. Results show that from 1850 to 1980, the column concentrations of anthropogenic aerosols increased significantly over the globe. The column concentrations of anthropogenic aerosols in PM_2.5 mainly increased in eastern North American, Europe and eastern China, and their changes in summer were more significant than in other seasons. The column concentrations of natural aerosols changed more obviously over several large deserts, and their changes in spring and summer were the most significant of all seasons. Anthropogenic aerosols contributed the largest to the variation of PM_2.5 column concentration in autumn(95%), but in spring their contributions were the smallest(28%), and in summer and winter their contributions were almost equal(46% and 41% respectively). From 1980 to 2010, the column concentrations of PM_2.5 and anthropogenic aerosols increased(especially in spring) in Southeast Asia, while decreased(especially in summer) in Central Europe and North American. Whereas, natural aerosols decreased sharply in desert regions during 1980 to 2010, and their changes were more significant in winter and spring. Variations of natural aerosols almost appear in deserts. The contributions of anthropogenic aerosols to the seasonal change of PM_2.5(less than 50% in all seasons) generally reduced comparing with that from 1850 to 1980.

The concentrations, profiles and seasonal variations of PCDD/Fs in ambient air around a municipal solid waste incinerator(MSWI) in Beijing from April 2013 to January 2014 were investigated. The mass concentrations and TEQ of 2, 3, 7, 8-substituted PCDD/Fs in the air samples ranged from 8.3 to 115pg/m³ and from 0.11to 1.9pg I-TEQ/m³, respectively. The concentration values at 1sampling site in autumn and all 5sampling sites in winter were higher than the ambient air standard of 0.6pg I-TEQ/m³ for dioxins regulated in Japan. 1, 2, 3, 4, 6, 7, 8-HpCDF and OCDF dominated PCDD/Fs in all the samples for all four seasons, while 2, 3, 4, 7, 8-PeCDF was the dominant congener contributing to TEQ. The spatial distribution basically exhibited a trend that the concentrations at site close to the MSWI(~400m) are higher whereas those at other sites(>1000m) are comparable and not related to the distances from the source. Seasonal variation showed obviously higher concentration in winter than the other three seasons, which may attribute to domestic heating and worse atmospheric dispersion that occur in winter. The homologue and congener profiles of PCDD/Fs in the air samples differed from those of the flue gas emission from the MSWI, consistent with the principal component analysis results, indicating that the concentrations of PCDD/Fs in ambient air were not affected by the MSWI exclusively, but jointly influenced by multiple sources. Dioxin inhalation exposure dose estimation showed that the dioxin inhalation exposure risk of residents living in the studied area was at a relative safe level(0.034~0.161pg I-TEQ/(kg·d)). However, the dioxin inhalation exposure risk in heavily polluted seasons still needed great concerns.

An experimental-scale electrostatic precipitator was built to investigate the characteristics of corona discharge and particle collection at various temperatures ranging from 90℃ to 450℃. The influence of several key parameters(temperature, applied voltage, particle concentration and gas flow velocity) on particle collection efficiency were analyzed, and the results indicate that the collection efficiency can reach higher than 98% as the gas temperature increases form 90℃ to 450℃, when the specific collection area(SCA) of the ESP is 46.5m²/(m³·s^-1) and the inlet mass concentration of particles is about 750mg/Nm³.The collection efficiency increases with the increase of applied voltage, yet the growth rate reduces gradually. At the same voltage, as the temperature increases, the corona current increases substantially, which enhances the particle charging and finally improves the collection efficiency. However, at the same corona current, the particle collection efficiency decreases because of the low electric field intensity at high temperature. The increase in gas flow velocity reduces the particle collection efficiency, and the influence of gas flow velocity on PM_1.0 removal is much more significant than PM₁₀. The increase in particle concentration enhances the collisions among particles and leads to particle coagulation, which is conducive to particle removal.

In order to expand the application field of struvite(MAP) pellet crystallization technology, the optimal conditions for struvite pellet formation at low phosphorus concentrations were investigated. Results show that the phosphorus concentration over 50mg/L would be better for application of this technology. The optimal conditions for struvite pellet formation were as follows:pH=9.0 and phosphorus to nitrogen molar ratio=1:8. Under the conditions, the average size of harvested struvite particle reached 0.56mm, the volume growth rate was 4.95cm³/h and the struvite purity reached 99.9%. In order to further optimize MAP formation in the fluidized bed reactor, CFD software(Fluent 6.3) was used to simulate the flow fed to the reactor. It turned out that the bottom-up hydraulic classification was formed obviously in the growing zone of the crystallizer. Velocity in the cross-section was relatively uniform, which is beneficial to struvite formation. But some adverse conditions such as dead zone, vortexes and circulation loops were also present in the settling and influent zones. Therefore, it is necessary to improve the connection between the growing zone and settling zone as well as the distribution of inlet pipes to obtain high-quality MAP pellets.

Key operational parameters of single-stage partial nitritation/anammox(PN/A) process was investigated to achieve higher nitrogen removal rate(NRR) and robustness by using a sequencing batch reactor(SBR)(120L) treating ammonia-rich wastewater. Long-term operation demonstrated that the maximum NRR of the reactor was 1.1kgN/(m³·d). The main parameters influenced the stability of the reactor were:free ammonia concentration, dissolved oxygen(DO) concentration and the relative proportions of the granules and flocs. The balance of AOB and anammox activity was the key to a robust single-stage PN/A operation. Excess discharge of floc sludge led to a decrease of ammonia oxidation rate and a high and inhibitory DO level to anammox bacteria, which eventually triggered the dramatic drop of NRR. The limiting factors of further improvement of NRR were:(1) sludge concentration stabilized due to biomass washout;(2) anammox and AOB activity could not be promoted simultaneously when further increasing DO levels;(3) mass transfer could not be further enhanced. Furthermore, NRR showed strong correlation with aeration rate in this study. Therefore, aeration rate could be an alternative regulating parameter under fluctuating influent load.

The degradation pathways and mechanisms of aniline aerofloat in an anaerobic reactor were investigated by UV, IC and GC-MS analysis. The results showed that total aniline aerofloat content of up to 44.18% were degraded within 48hours. N, P and S elements in aniline aerofloat were partially converted into NO₃^-, PO₄^3- and SO₄^2-, respectively, according to IC analysis. The main degradation intermediates were monitored by GC-MS and determined as aniline, 2, 5-bis(1, 1-dimethylethyl)-, C₁₃H₂₃C_l3O₂, 1-nonadecene, docosane and eicosane. It is proposed that the aniline aerofloat was firstly degraded into aniline, phosphate and sulfate, and was then deaminizated to form phenol, 2, 5-bis(1, 1-dimethylethyl) and NO₃^-, which are further degraded to chain hydrocarbons including 1-nonadecene, docosane and eicosane.

As the functional part of denitrification, denitrifier was obviously stressed by anions. To investigate the effects and the mechanism of anions on heterotrophic denitrifying sludge(HDS) are of great significance for the practical application of high-rate denitrification in saline nitrogen-rich wastewater treatments. Nitrate reductase and alkaline phosphatase were chosen as the indices to determine the effects of Cl^-, SO₄^2- and PO₄^3- on the enzyme activities in HDS, while the ratios of live/dead cells and cellular morphology were examined and observed to characterise the effects of Cl^-, SO₄^2- and PO₄^3- on the cell structures in HDS. Results showed that, the IC50values of Cl^-, SO₄^2- and PO₄^3- for nitrate reductase were 0.15, 0.12 and 0.05mol/L respectively, while the IC50values of Cl^-, SO₄^2- and PO₄^3- for alkaline phosphatase were 1.14, 0.75 and 0.49mol/L, respectively. Anions with high concentrations(1.71mol/L Cl^-, 0.85mol/L SO₄^2-, 0.57mol/L PO₄^3-) resulted in the damage of cell membranes, and caused the leakage of cell inclusion. In conclusion, the effects of anions on HDS were attributed to the osmotic stresses which affected the enzyme activities, and the ion stresses which caused the damage of cell membranes.

To investigate catalytic oxidation of ammonium from groundwater by a co-oxide filter film coating on quartz sands, a pilot-scale filter which has been operated for about 4years was used, and varying inlet ammonia loads and the filter was operated under inlet water only containing ammonia for long term. Results showed that in the experimental conditions of the concentration of ammonia nitrogen was 0.8~1.3mg/L, the temperature of raw water was 20~23℃, and the flow rate was 7m/h, the performance of catalytic oxidation of ammonium of the co-oxide filter film remained stable and high-efficient for a long time. The maximum ammonium removal capacity of the filter was determined to be 22.2g NH₄⁺-N/(m³·h) with ammonium removal rate(ARR) determined by the ammonium loading rate(ALR) if the dissolved oxygen(DO) was enough. The maximum concentration of ammonia was limited by DO. When the DO in influent was not enough, flow rates had significant influence on consumption of dissolved oxygen along the filter layer.

The reactivation performance of nitrosation granular sludge(NGS), which had been stored at 24~29℃ for a long-term of 1a, was investigated in a sequencing batch reactor(SBR) fed with inorganic synthetic wastewater, via the gradually increasing of the influent ammonia nitrogen loading from 0.32 to 0.64kg/(m³·d) and initial concentration of free ammonia from 3.7 to 7.2mg/L. High throughput sequencing technology of Miseq was also employed to analyze the variation of microbial community before and after the reactivation. Results showed that the stored NGS could be reactivated in a short period of 8days, since the removal effciency of ammonia nitrogen and the accumulation ratio of nitrite nitrogen were higher than 95% and 80%, respectively. Meanwhile, both sludge particle size and extracellular polymer substances(EPS) contents decreased significantly. After 20days reactivation, the specific ammonia nitrogen removal rate of 24.6mg/(gVSS·h) and the specific nitrite accumulation rate of 23.8mg/(gVSS·h) were observed, while average particle size of NGS remained at 0.5mm. During this period, the microbial diversity of NGS decreased obviously, ascribed to the washing out of most of anaerobic and heterotrophic bacteria. The relative abundance of ammonia-oxidizing bacteria, such as Nitrosomonas ect., increased from 1% to 58%, and the growth of nitrite-oxidizing bacteria was inhibited selectively. It indicated that the NGS after a long-term storage could be inoculated in SBR to achieve its rapid start-up.

Husk ash of Jatropha curcas seeds were pyrolyzed and charred for 50min at 300~700℃ to obtain biochar after phosphoric acid treatment. The influence of some parameters such as biochar dosage, contact time, and temperature on the naphthalene, anthracene, phenanthrene, and pyrene removal by the biochar was investigated. In addition, the sorption efficiency and mechanism of the biochar on polycyclic aromatic hydrocarbon(PAH) were studied. Results showed that the maximum removal rate of naphthalene, anthracene, pyrene and phenanthrene was 97.4%、94.6%、93.1% and 92.1%, respectively, under the following conditions:temperature 25℃, contact time 60min, the initial concentration of the four PAHs 30mg/L, and dosage of biochar 0.15g. All results suggest that the sorption of the four PAHs by the biochar followed the second-order kinetics model very well. Moreover, the Langmuir model gave an acceptable fit to the experimental data. Maximum uptake of naphthalene, anthracene, pyrene and phenanthrene was 8.849, 8.547, 8.097 and 7.633mg/g, respectively.

The formation and mechanism of assimilable organic carbon(AOC) production after chlorination is evaluated through analyzing variation of molecular weight(MW) distribution and hydrophobic/hydrophilic fractions. The experimental results showed that the hydrophobic part of AOC was dominant, followed by transphilic and neutral hydrophilic fractions. The charged hydrophilic fraction was the least. It was found that chlorine reacted mainly with hydrophobic organics with low MW, leading to the most AOC formation. By investigating the variations of organics of MW and fractions through advanced treatment process, it was found that hydrophobic fraction was reduced and hydrophilic fraction was increased gradually, indicating the decrease of AOC formation after chlorination. It can be concluded that hydrophobic organics with low MW is the main precursor of AOC after chlorination.

Based on the theory of passive sampler and stir bar sorptive extraction(SBSE), a novel passive sampler with a multi-walled carbon nanotubes/polydimethylsiloxane(MWCNTs/PDMS) coating by stir bar sorptive extraction was invented to monitoring micro-pollutants in the water. In this study, phenol(PhOH), diethylstilbestrol(DES) and lead(PB) were selectedas the target pollutants to test and verify the performance of absorption capacity and optimize the adsorption conditions of this novel passive sampler. The results showed that, compared to a commercial one, our self-made passive sampler with MWCTNs/PDMS sorptive coatingcan quickly reach the adsorption equilibrium time and had greater adsorption capacity. Methanol was an optimaldesorption solution for PhOH and DES, and 0.6mol/L HNO₃ was perfect for Pb. Recirculated desorption experiments show that the new passive sampler could be used more than 50times and after than the desorption efficiency can still reached more than 70%, indicating a good stability and reusability.

The effects of temperature stress on different nutrition type methanogens in an upflowed anaerobic sludge blanket(UASB) reactor was investigated by batch culture. The results showed that the dominant hydrogenotrophic and acetotrophic methanogens in this reactor were Methanospirillum and Methanosaeta, respectively. Under 35℃ condition, the accumulative methane production from hydrogenotrophic and acetotrophic methanogens were 24.7 and 11.7mL, separately. And the maximum methane production rate(R_max) were 0.74 and 0.18mL/h, respectively. Temperature decreases, from 35℃ to 30, 25, 20, 15℃, resulted in accumulative methane productions from hydrogenotrophic methanogens were decreased by 14.2%, 34.0%, 47.0%, 57.5%, respectively. While those from acetotrophic methanogens were reduced by 5.1%, 23.9%, 45.3%, 95.7%, separately. These results indicated that hydrogenotrophic methanogens are more sensitive to temperature tress at 20~30℃, while acetotrophic methanogens are more sensitive at ≤15℃.

In this paper, the pre-magnetization of sludge was carried out using electromagnetic field, and the effect of electromagnetic field intensity and time on the coagulation efficiency was investigated. The results indicated that the turbidity and DOC removal efficiency of recycling magnetized sludge can be improved, the removal of which was 3.7% and 32.4% respectively higher than the cases without electromagnetic field. Sufficiently large magnetic field intensity and magnetization time played a significant effect on the enhancement of the coagulation efficiency. The Zeta potential of the mixed water and sludge increased by electromagnetic field and the flocs characteristics were obviously improved, accordingly the flocs had bigger growth rate, average flocculation index and average flocs size with denser and regular structure.

The scientific gap of operating parameters of combined thermal and ultrasonic disintegration at low temperature of waste activated sludge(WAS) still needs to be filled. This study provides more insights into the technical feasibility of low organic WAS disruption pretreated by combined thermal at temperature lower than 100℃ and ultrasonic technique. Optimization of combined thermal and ultrasonic disintegration of WAS for enhanced organic releasing was carried out using response surface methodology(RSM) and Box-Behnken design of experiment. The quadratic effects as well as the interactive effects of temperature and specific energy on the disintegration degree of SCOD, soluble concentration of protein and carbohydrate were investigated. Results indicated that quadratic effect of temperature was more significant in affecting sludge disintegration than specific energy and regression models had good fitness with experimental results. The optimum disintegration degree of SCOD, soluble concentration of protein and carbohydrate achieved were 39.01%, 1360.59mg/L and 334.52mg/L, respectively, at 80℃ and 12000kJ/kg TS. In addition, the verification experiments appeared high coincide degree with predicted results, indicating that the models were reliable for application and promotion of combined thermal and ultrasonic disintegration.

This study investigates influence factors and thermal degradation of decabromodiphenyl ether(BDE-209) under the temperature range of 200~300℃. The results indicated that pyrolysis of BDE-209 was affected by temperature, time and common metal salts which were produced during the manufacturing and processing of printed circuit boards, such as copper nitrate, ferric chloride, aluminum chloride and zinc chloride. Pyrolysis of BDE-209 could be accelerated with the rise of temperature and extension of pyrolysis time. Results showed a greater impact of temperature on pyrolysis than that of time. A significant acceleration of pyrolysis was detected with copper nitrate, ferric chloride and aluminum chloride with degradation rates of BDE-209 in copper nitrate >ferric chloride >aluminum chloride. Pyrolysis of BDE-209 was inhibited with the presence of zinc chloride. Acceleration of aluminum chloride and inhibition of zinc chloride were weakened with the increase of temperature. This research results can provide a scientific basis for further study on the release and degradation of BDE-209 from electronic waste during the thermal treatment.

The wastewater containing high concentration(5562.71mg/L) of nickel ion was first completely precipitated at pH 9, and subsequently treated by a ceramic microfiltration membrane with a pore diameter of 0.5μm. During the concentration process, the membrane flux(J) dropped significantly at the initial stage, then declined slowly, and finally decreased at a rapid rate again. The nickel rejection coefficient(R_Ni) was found to be approx. 1. When the volume concentration factor(VCF) increased from 1to 10, the nickel concentration in the retentate(C_r) increased from 5562.71 to 55507.76mg/L, whereas the nickel concentration in the permeate(C_p) remained nearly constant at approx. 13.26mg/L. Then, the complexation-ultrafiltration process was studied using the permeation fluid from the microfiltration process as the feed solution. Poly(ethylene imine) was employed as the complexing agent. The effects of the polymer/metal mass ratio(r_p/m), pH, temperature and operating pressure on R_Ni and J were investigated. Further, the process of ultrafiltration concentration was studied. The results showed that R_Ni increased with increasing r_p/m or pH and decreased slightly with temperature, and that the operating pressure exerted no effect on R_Ni; J increased with temperature or operating pressure. With increasing pH, J increased at first, and then reached a constant value. The effect of r_p/m on J was insignificant. The ultrafiltration concentration experiment was carried out at r_p/m=7 and pH=9. When VCF increased from 1to 30, J only declined by 9.76%. C_r increased linearly from 13.26to 396.64mg/L, whereas C_p remained roughly unchanged at about 0.04mg/L. Nickel ions were concentrated effectively, and the permeation solution from the ultrafiltration process was discharged directly.

In order to correctly evaluate the environmental risk of the new insecticide CYC, the influence of the CYC initial concentration, temperature, initial pH, concentration of hydrogen peroxide and nitrate on the CYC photodegradation in water were studied. The results show that the photodegradation of cycloxaprid was fitted to pseudo-first-order kinetics reaction. For direct photodegradation, cycloxaprid photolysis rate was accelerated with the decreasing of CYC concentration and the increase of temperature. The activation energy of photochemical reaction was 21.27kJ/mol. By measuring the CYC pKa value of 3.42 and simulation CYC reactivity of different forms of light particles, known the complicated influence of pH value on CYC photolysis:In the acidic conditions, the degradation rate of cycloxaprid depended on the different cycloxaprid forms(cations and neutral particles) and their singlet energy values. While, in the alkaline condition, the photodegradation rate was mainly affected by the number of hydroxyl radicals in the solution. For CYC indirect photodegradation, nitrate and hydrogen peroxide were confirmed to promote the role. When evaluating the environmental risk of CYC should comprehensively consider the effect of environmental factors on its degradation.

In order to analyze the influence that parameter uncertainty has on groundwater solute transport numerical simulation, this study adopted Monte Carlo simulation to conduct an uncertainty analysis on an example and illustrated its results from the perspective of risk assessment. For the purpose of reducing computation load, Sobol' method was used to analyze the sensitivity of model parameters, which helped to select the more sensitive parameters as random variables and to construct the Kriging surrogate model of the simulation model. This surrogate model provided further help in achieving the Monte Carlo simulation. Results showed:when the confidence was 80%, the confidence intervals of well 1, 2, 3 were 23.46~42.06, 47.99~66.73, 69.54~82.94mg/L, respectively. Combined with risk assessment, the risk of groundwater contamination was calculated as 0.54, which could serve as a scientific guide for the prevention and control of groundwater pollution.

Miseq high-throughput sequencing technique was used to investage the bacterial community structure of nitrogen removal process in source water experiment systems added aerobic denitrification bacteria. Bioinformatics analysis were carried on the for the samples of bacteria and control systems. Then, the fundamental analysis, Optimized sequence statistics, OTU distribution, and Taxonomic analysis; the Advanced analysis, the microbial community, PCA, Rank-Abundance, Hcluster, Specaccum, and Venn of OTU distribution. As a result, the nitrogen of bacteria system was removed obviously, and Hierarchical cluatering and PCA showed that the microbial community structure of bacteria and control systems has changed, and the Protebacterice and Bacteroidetes were the main phylum in experiment systems. Meanwhile, the N-functional microbial of bacteria system had an increase process, obviously, which was consistent with the changes of aerobic denitrification bacteria. From all the results, the Miseq high-throughput sequencing technique was an effective tool to explore the changes of bacterial community structure of nitrogen removal process, which could supply a reference to study the changes of community structure of remediation the source water in situ.

In order to investigate the influences of activated sludge aerobic granulation process on microbial diversity and the differences of microbial community structure in aerobic granular sludge(AGS) which was cultivated by different carbon sources or different granulation methods, the microbial community structure of seed sludge and AGS(AGS with artificial wastewater, AGS with real domestic wastewater by adding diatomite and powered activated carbon respectively) were analyzed by PCR-DGGE. The activated sludge aerobic granulation process led to a low microbial diversity. The bacteria which might impact the stability of granular sludge were eliminated. However, the bacteria which were capable of phosphorus accumulation, denitrification or bio-degradation of refractory organic substances were retained. In the activated sludge aerobic granulation process the ammonia oxidation bacteria(AOB) were enriched to a certain extent. Compared with the seed activated sludge, the diversity index and evenness index of AOB were increased. The dominant bacterial communities in AGS were Proteobacteria, Bacteroidetes and uncultured bacterium. The dominant AOB in AGS were all belonged to Nitrosomonas.

Occureneces and distributions of iron forms in the sediment cores from three typically zones of Lake Taihu, i.e. phytoplankton dominated zone, macrophyte dominated zone, and phytoplankton-macrophyte transition zone, were investigated using the sequential extraction procedure. Generally, the total iron contents decreased in the order:phytoplankton dominated zone(31.57±8.51mg/g) >phytoplankton-macrophyte transition zone(30.34±11.97mg/g) >macrophyte dominated zone(25.25±4.59mg/g), while the contents of different iron forms in the interest sites followed the variations:reducible oxides Fe_ox2 >carbonate associated Fe Fe_carb >easilyreducible oxidesFe_ox1 >poorly reactive sheet silicate FeFe_prs >magnetite Fe_mag >Absorbed Fe(Ⅱ), Fe_carb、Fe_ox1、Fe_ox2 weremeasured to be7.79mg/g, 6.16mg/g, 8.18mg/g, accounting for 28.56%, 21.54%, 29.53% of total iron respectively, suggesting those highly reactive iron Fe(Ⅲ) were the dominated iron forms. The concents of different extracted phosphorus in sediment decreased in the order:NH₂OH·HCl-P >MgCl₂-P >NaAc-P >Na₂S₂O₄-P >Concentrated HCl-P >(NH₄)₂C₂O₄-P. Three dominated phosphorus fractions including MgCl₂-P、NaAc-P、NH₂OH·HCl-Pwere measured to be 0.067mg/g, 0.061mg/g, 0.068mg/g, accounting for 35.28%、31.97% and 22.55% of the total extracted phosphorus.Significantly positive relationships were observed between the extracted phosphorus and iron fractions using the sequential extraction(P<0.05), further confirming the concomitant release of phosphorus from reduction dissolution ofFe(oxyhydr) oxides in sediments.

To explore phytoplankton community structure and seasonal variations in a temperate seasonally stratified reservoir in North China, water samples were collected twice a month from different depths of Zhoucun Reservoir, Zaozhuang City, Shandong Province, from July 2014 to June 2015. The phytoplankton community was divided into functional groups following the method described by Reynolds and Padisák. Hydrological and water quality patterns were considered to reveal the driving forces for the selection of phytoplankton functional groups. The results suggested that a total of 112 species of phytoplankton, belonging to seven families and 63 genera, were detected and could be sorted into nineteen functional groups. Phytoplankton dynamics in Zhoucun reservoir exhibited remarkable seasonal variations:The S1functional group(Lyngbya sp. and Spirulina sp.) was dominant during thermal stratification in summer and autumn; while C+D functional groups(Cyclotella meneghiniana and Synedra sp.) were dominant during the mixing period(winter) under conditions of low temperature and light level. The distribution of phytoplankton functional group showed unobvious difference in vertical. Redundancy analysis(RDA) showed that thermal stratification, precipitation and water temperature had a major influence on phytoplankton succession in Zhoucun Reservoir.

The inhibitory effect and possible inhibitory mechanisms of lactic acid on M. aeruginosa were studied. The results showed that lactic acid had a strong inhibiting effect on the growth of M. aeruginosa, 72h, except the inhibition rate of experimental group in lowest concentration was 60%, the rest inhibition rate of experimental group were reached more than 80%; under the stress of lactic acid, the contents of nucleic acid and protein, the electrical conductivity(EC) in M. aeruginosa supernatant all increased, the contents of malondialdehyde(MDA) and oxygen free radical(O₂^·) of M. aeruginosa cells enhanced, the activity of superoxide dismutase(SOD) decreased, and transmission electron microscope photographs showed that ultrastructure of M. aeruginosa cells had changed obviously. All the results indicated that the possible inhibiting mechanisms were that lactic acid changed the permeability of M. aeruginosa membrane and the cell structure, decreased its antioxidant capacity, and caused the crack and death of the cell in the end.

In order to investigate the response of the macroalgae to heavy metal contamination, the influence of three heavy metal ions(Cu(Ⅱ), Zn(Ⅱ) and Pb(Ⅱ)) on the uptake of nitrate by Ulva prolifera was investigated. Kinetic parameters related to nitrate uptake in different trials were determined by the batch culture experiment in the laboratory. The results showed that the uptake of nitrate by Ulva prolifera was promoted at low concentrations of Cu(Ⅱ)(<0.04mg/L) and Zn(Ⅱ)(<0.12mg/L) and inhibited at high concentrations(Cu(Ⅱ)>0.10mg/L and Zn(Ⅱ)>0.20mg/L). Pb(Ⅱ) played a negative role in the uptake of nitrate by Ulva prolifera at all tested concentrations. The inhibition rate of the maximum absorption rate of nitrate(V_max) were calculated to be 0.23mg/L, 0.66mg/L, and 0.63mg/L for Cu(Ⅱ), Zn(Ⅱ), and Pb(Ⅱ), respectively. The inhibition effects of the three heavy metals at concentrations >0.5mg/L on Ulva prolifera nitrate uptake were observed to be in the order of Cu(Ⅱ) >Pb(Ⅱ) >Zn(Ⅱ).

From 2009 to 2011, four field surveys were carried out in East Tiaoxi River watershed. The forms of nitrogen and phosphorus and their spatial variability were analyzed. East Tiaoxi River could be divided into three sections, namely upper reach, middle-up reach and middle-lower reach, and characterized by hilly river, river influenced by urban and plain river, respectively. The results showed that dissolved nitrogen was the main nitrogen species in water, and nitrate(NO₃^--N) was the major form of dissolved total nitrogen(DTN) species. Meanwhile, phosphorus in particulate form was slightly more abundant than that in dissolved form(dissolved total phosphorus(DTP)) in the samples. And the relative partition of DTP to TP decreased along the river flow. The dissolved organic nitrogen(DON) and phosphorus(DOP) accounted for 22% and 42% of DTN and DTP, respectively, with a significant positive correlations as well. The higher ammonia nitrogen(NH₄⁺-N), DOP and orthophosphate(PO₄^3--P) in middle-up reach, accompanied by the positively correlated conductivity with NH₄⁺-N and DOP, indicated that the discharge of urban sewage probably affected the contents and species of nitrogen and phosphorus. The positive correlations between turbidity and all forms of phosphorus revealed that the inputs of mineral particles or sediment resuspensions, which were induced from mining, navigation and digging in lower reach, may be important sources of phosphorus. Finally, the slight reduction of DTP in middle-lower reach was also observed, which was probably induced by adsorption of dissolved phosphorus into the surface of mineral particles.

Studing the effects of changing precipitation regimes and increasing nitrogen deposition on the key processes of nitrogen cycle in grassland ecosystem and exploring the additive effects and the adaptation characteristics of them responding to the future global climate changes were helpful to provide scientific basis for regulating nitrogen transformation processes, improving grassland nitrogen use efficiency and reducing the negative ecological effects. In this paper, different effects induced by water and nitrogen additions and their co-effects on plant and soil nitrogen pools were reviewed. Meanwhile, the possible drive mechanisms related to the changes in microorganisms and enzymes under these conditions were analyzed. On this basis, the uncertainties about the effects of changing water and nitrogen on the key processes of nitrogen cycle in grassland ecosystem as well as the main problems existing in current related studies were also discussed.

In recent decades, the Luan River Basin has been changed significantly by human activities. The runoff and sediment load decreased sharply. The influences of Luan River on the coastal marine environment also changed. Therefore, this study focused on the relationships between estuary environment status and Luan River discharge in recent years. In this study, 33surface sediment samples were collected from Luan River Estuary. Grain size and concentrations of total organic carbon(TOC), heavy metals(Cu, Pb, Zn, Cd, Cr, Ni, As and Hg) and PAHs(16US EPA priority PAHs) were analyzed. The mean concentrations of Cu, Pb, Zn, Cr, Ni, Cd, As and Hg were 18.76, 30.98, 44.63, 41.14, 15.60, 0.09, 7.21 and 0.02μg/g, respectively. High concentrations were observed in the samples with fine particles that were collected from the estuary and south part. The concentrations of heavy metals were highly correlated to each other. Human discharges and natural sources contributed 64.2% and 35.8% of heavy metals in this region, respectively. Distinctly different distribution patterns were presented by PAHs and heavy metals. PAHs species were dominated by 4rings compounds. There was no correlation between PAHs concentration and TOC, grain size or heavy metal contents. Luan River played a much smaller role on the inputs of PAHs than heavy metals in this region. 40.3%, 46.7% and 12.0% of PAHs in this region originated from pollution of oil and oil-products, combustion of fossil fuel and biomass and exhaust of vehicles and ships.

BCR three stage sequential extraction procedure was applied to examine the spatial occurrence characteristics and relative ratio of the speciation of Cr, Ni, Cu, Zn, As, Cd, Hg and Pb in the sediments from Danjiangkou reservoir, and meanwhile their stability and pollution assessment were discussed. All types of metals had obvious spatial heterogeneity; their high value was grouped in the middle of the reservoir, the west of tributaries and the northwest of Danjiang reservoir. Most metals mainly existed in residue state except for Pb and Cd, the reducible Pb and acid soluble Cd respectively accounted for 54.91% and 42.19% of the total content. The stability of eight studied metals was in the order of Cr >Pb >As >Ni >Cu >Hg >Zn >Cd. Cd was unstable in most studied sites, and there was higher risk of quick desorption and release.

Contents of 26 heavy metals in the 39 offshore surface sediments of Jiulong River were determined by inductively coupled plasma mass spectrometry(ICP-MS), atomic fluorescence spectrometry(AFS) and atomic absorption spectrometry(AAS). Geo-accumulation index and potential ecological risk index were applied to evaluate the pollution degree and potential ecological risk of heavy metals, and multivariate statistical methods were applied to speculate the main sources of these heavy metals. The results showed that the distributions of heavy metals were different in three regions of Jiulong River(north creek, western creek and estuary), the high contents of Mn, Zn, Cd, Mo, Sb, Cs, Y, Th and U elements appeared in the north creek and western creek, and the high contents of Fe, Ni, Cr, V, Co, Sc, Li, Rb, Sr, Tl and Ga elements appeared in the estuary. Most of these elements were enriched in the sediments. The results of pollution assessment by geo-accumulation index revealed that the pollution degree of Cd was the highest and at a serious polluted level in 10.3% of the samplings. The assessment results of potential ecological risk indicated that the potential ecological risk of heavy metals showed the order of Cd >Hg >Cu >Pb >Ni >Co >Cr >Mn >Zn >V. Cd and Hg contributed the most to the total potential ecological risk, accounting for 78.1% and 12.1%, respectively. The results of multivariate statistics analysis indicated that the source of Fe, Mn, Zn, Pb, Cu, Cr, Cd, Hg, Mo, Sb and Bi were mainly from agricultural activities and mining activities; the source of Ni, Co, Sc, Li, Rb, Sr, Be, Ga and Tl were mainly from burning fossil fuels; and the source of Ba, Y, V, Th, U and Cs were mainly from the rock weathering of granite.

It was to clarify the effect of Corbicula fluminea or algae under physical and Chironomus plumosus combined disturbance on regeneration and transformation of internal phosphorus(P), using the sediment and overlying water from Meiliang Bay, Tai Lake. The variation of P forms in the overlying water, pore water and sediments was analyzed. The results showed that the concentration of Total P(TP), Dissolved total P(DTP), Dissolved inorganic P(DIP), Particulate P(PP) in the overlying water under combined disturbance with the Corbicula fluminea or algae were obviously higher, compared with that under combined disturbance, and they could result in the decrease marked for DIP in the pore water. In addition, the peak area of DIP migrated deep(from 3~4 cm to 4~5 cm under 0 cm) dued to Corbicula fluminea or algae, but the control was not. The content of NH₄Cl-P and the percentage of Fe/Al-P to Total P in the sediment(0~4cm) decreased and the Fe/Al-P increased due to Corbicula fluminea or algae, and the effect of Corbicula fluminea or algae on the NH₄Cl-P decreased and Fe/Al-P increased was the same nearly. Under different disturbance factors, the contribution of Chironomus plumosus on the DTP and DIP in the overlying water was big. One explanation was it reduced the DIP in the pore water and the NH₄Cl-P in the sediment. It was suggested that Corbicula fluminea or algae under combined disturbance could improve the internal P release and migration.

In order to eliminate the externality of ecological and environmental protection activities, it was suggested that providing the ecological compensation to upstream area is necessary for Pareto optimality according to the concept of margin value. Three modes were investigated for Pareto improvement, including the mode of paying compensation to upstream area, the mode of combination of paying compensation to upstream area with imposing tax from downstream area and the mode of determined by negotiation between upstream and downstream area. Taking the Minjiang River basin for example, the revelent data from 1999~2013was analyzed, which focused on the ecological environment protection and the relevant regional GDP in the basin between upstream and downstream. The results indicated the two-step possible way is effective to realize Pareto improvement optimality. Firstly, the mode of combination of paying compensation to upstream area and composing tax will be used to obtain the maximum utility for both upstream and downstream area, namely more than 2.6026 billion Yuan for taxation respectively. Moreover, the mode of determined by negotiation should be used to distribute the net income, in further to maximize their benefits and eventually achieve the Pareto optimality.

To investigate the effect of difenoconazole on zebrafish antioxidases, adult zebrafish were exposed to three concentrations of difenoconazole for 15days. The activity of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GPx) and glutathione reductase(GR) was measured at 3, 8 and 15 days post exposure(dpe) respectively. Results indicated that the brain CAT activity was increased at 3 and 8 dpe but decreased at 15 dpe. 50μg/L or higher difenoconazole could inhibit brain and hepatic GPx activity of zebrafish, and the inhibition in brain was stronger than liver. In addition, brain GR activity was induced by 500μg/L difenoconazole while hepatic GR activity was reduced under the same exposure. These results implicated that 50μg/L could alter the antioxidant system of zebrafish and its effects on fish living in agricultural water areas should be concerned.

This paper proposes an airport noise ensemble prediction model based on space fitting and neural network by introducing ensemble learning method. Space fitting and BP neural network is used respectively to create the base learner and a heterogeneous ensemble algorithm based on observational learning is used to integrate these base learners. The final ensemble model thus can improve prediction accuracy effectively by integrating multiple heterogeneous base prediction learners. The experimental results shows that the proposed heterogeneous ensemble algorithm based on observational learning is better than other heterogeneous ensemble algorithms on accuracy and tolerance for solving the airport noise prediction problem.

Non-point source pollution(NPS) had deteriorated water quality in Miyun Reservoir watershed. GIS technology, ArcSWAT model, and statistics analysis were coupled to identify the zonation of NPS control in Chaohe river watershed, one main tributary in northeast of Miyun Reservoir watershed, with relative strong intensive agricultural activities. The results showed that annual average loads of TN and TP were 563.3t/a and 28.7t/a, respectively. The spatial distribution of NPS pollution load was greatly diverse with different precipitation and terrain in Chao river watershed. In high flow year, the agricultural land at higher elevation had the highest NPS pollution loads, whereas in the normal and low flow year, the agricultural land and livestock area also contribute the major pollution load; the fertilizer application amount was identified as the most important factor of TN and TP loss. Meanwhile, the slope length, soil type, land use, and slope degree were also more important factors; The content of organic P in soil may contribute to TP loss due to long term cultivation and overuse of fertilizer in Chaohe river watershed; Three zones for NPS control in Chaohe river watershed were divided as pollution control zone where the agricultural activities was intensive, pollution treatment zone where was livestock breeding area and villages, ecological restoration zone where was high soil erosion at higher elevation.

In large geographic area, multiple sources release multiple stressors and affect multiple habits and endpoints. The diversity and complexity of the interaction between sources, stressors and habits is one of the challenges of Regional Environmental Risk Assessment(RERA) for large geographic areas. Meanwhile, the existed assessment methods do not pay enough attention on the release rules of risk factors, the distribution patterns of risk factors in space, and the path and the degree of the damage on receptors caused by risk factors. The theory of Risk Field(RF) was applied to analyze the generation mechanism of risk field and the influence mechanism on risk receptors. The environmental risk of Nanjing Chemical Industry Park was investigated as the example. At first, the environmental risk sources were identified. Then, methods, like Set Pair Analysis, were used to construct environmental risk field of various risk sources. After analyzing the environmental risk receptors in the risk field, the distribution of regional environmental risk level could be obtained. The densely populated areas or ecologically sensitive areas located around the risk sources or the river downstream had higher environmental risk level(environmental risk value R≥6), which was in good agreement with the actual situation. This paper suggested establishing the prevention-oriented environmental risk management system based on the classification results of the environmental risks.

Because the relevant environmental damages were not incorporated into evaluating conventional water-use efficiency, this efficiency indicator was incapable of depicting the real comprehensive effects except economic outputs. The concept of environment-economy integrated efficiency for regional water use(WEEE) was raised along with its evaluation method based on a combination of DEA and Malmquist index. The WEEE of Henan province was then studied by using the data on water uses and related economic outputs and pollution discharges from 2001 to 2012. In contrast to a higher level economic efficiency, a lower level environmental efficiency had been witnessed for water uses of the province. To a large extent due to a poor environmental efficiency, the provincial WEEE was dragged down by about 2% if compared to the sole economic efficiency. Meanwhile, the cities with WEEEs of inefficient DEA in the province had exhibited the problems of low efficient water uses and excessive pollutant discharges. The averaged input redundancy rate of water resource reached 18% in 2012, and the extra emission rates of COD and NH₃-N were about 49% and 49.2% respectively. An analysis of variations of the total factor productivity(TFP) indicated that the technical change index was the most influential factor, resulting in an annually averaged decline of 2% in Henan's WEEE in the study period. Thus, it was recommended that more inputs need be made into technical innovations to realize water saving and water pollution control. The total volume control of water use should be enforced along with abatement of water pollutants.