Aerosol optical depth and cloud data from satellite measurements, the precipitation data from ground observations were used to evaluate the spatial-temporal variations of aerosol characteristics and the interaction between aerosols, cloud and precipitation. The results showed:1. The spatial distribution of aerosol optical depth in Xinjiang had a significant regional and seasonal variation due to the change of regional warm-dry conditions over the last decade. 2. The aerosol optical depth in South Xinjiang was higher than North Xinjiang. It was high in spring and summer and low in autumn and winter. It demonstrated an increasing trend. Wherein, aerosol optical depth in North Xinjiang changes more significantly. 3. There was a negative correlation between cloud optical depth and aerosol optical depth. Due to the influence of climate changes and size differences among particles, the correlation coefficient between cloud optical depth and aerosol optical depth in North Xinjiang was higher than South Xinjiang. 4. The cloud water path was greatly affected by temperature and humidity, and the sensitivity of the change of aerosol optical depth was greater than the southern. It was highest in summer and lowest in winter. 5. The relationship between aerosol optical depth and effective radius of cloud droplets was complex. They were greatly influenced by water vapour. When the water content in clouds was low, the effective radius of cloud droplets was negatively correlated with the aerosol optical depth. This indicated that the increase of aerosols in dry areas or seasons will inhibit the increase of cloud droplets. On the whole, the increase of aerosols in Xinjiang province suppressed regional precipitation.

For PM_2.5 pollution investigation in China, the air quality modelling system WRF-CMAQ was applied to calculate the impacts of ammonia emission on PM_2.5 concentration. The results indicated that ammonia emission had the biggest contribution for secondary nitrogen particles, with annual average 99.8% for nitrate, 99.7% for ammonium, while only 4.2%, 29.8% for sulfate and PM_2.5 respectively. Quantification of ammonia emission impacts on PM_2.5 mass concentration were also conducted in January, April, July and October as representative months, counted 20.15μg/m³, 12.39μg/m³, 13.20μg/m³ and 14.20μg/m³, respectively, with January ranking the first in monthly average contribution. It's general that ammonia emission had dramatical influence on PM_2.5 in regions where agriculture and animal husbandry well developed, such as Henan, Shandong, Hubei and Hebei province, with annual average contribution all exceeded 20μg/m³. In view of this, ammonia emission control will lead to significantly decrease of nitrate and ammonium, therefore reduce the PM_2.5 pollution level.

Two rice growing seasons with contrasting climate conditions was employed to study the effects of high temperature (2.6℃ above normal average) and low precipitation (36% lower than normal average) on CH₄ and N₂O emission and yield of six rice varieties (Huayou 14, Xiushui 134, Qiuyoujinfeng, Hanyou 8, Hanyou 113, and Zaoyuxiangjing). The results showed that total CH₄ emissions of all varieties in the rice growing season with high temperature and low precipitation were 1.8~9.6times (4times in average) of that values in the normal season. High temperature and low precipitation condition caused yield loss by 2.4%~22.1% (12.5% in average) of four varieties (Huayou 14, Qiuyoujinfeng, Hanyou 8, and Hanyou 113), and the average reduction rate of 8.6% for Water-saving and Drought-resistance Rice (Hanyou 8 and Hanyou 113) was much lower than that of 16.0% for non-WDR rice (Huayou 14 and Qiuyoujinfeng). The N₂O emission from rice paddies was characterized by pulse and short-interval, and dependent mainly on fertilization and water management rather than climate condition or rice variety. CH₄ emission was the major contributor in greenhouse gases emission in rice paddies under both climate conditions. The results indicated that CH₄ emission reduction should be paid attention to mitigate greenhouse gases emission from rice paddies in global climate change scenario in the future.

In view of the widely available data of the average speed in traffic systems and the parameter of operating mode distribution needed in emission models, a model was developed for generating operating mode distribution based on the average speed. Genetic Algorithm was used further for optimizing the model. After a comparison with the real-world data, it was found that the average emission rates estimated based on the proposed model exhibited less errors than those estimated based on MOVES in 82.5% of the speed bins. The highest error based on the proposed model was 50% while 304.2% based on MOVES. Finally, the proposed model was used to estimate emissions in Beijing for pre- and after- the implementation of the vehicle restriction policy. It was found that the 2nd Ring Road has experienced a reduction of total emissions of HC, CO, NO_x by 9.58%, 11.41%, 0.49% respectively. Compare with the test values, the R² with the model were higher than 0.700 and errors of the model were much lower than that of the MOVES. Further a modal application was proposed, which can calculate the traffic exhaust emissions of dynamic network.

The effect of internal recycle on the nitrogen removal by an ANAMMOX UASB reactor at different stages was investigated by changing the operating conditions. The reactor was inoculated with ANAMMOX sludge and fed by synthetic inorganic wastewater at 30℃±1℃. The ANAMMOX reactor was successfully started up in 42days, with total nitrogen(TN) removal efficiency of 76.04% at the loading of 3.26kg/(m³·d). During the initial stage, the effects of internal recycle on the performance of ANAMMOX UASB reactor were completely different for the start-up and mature stage, where the internal recycle (at recycle ratio of 92%) had negative effect on the TN removal(the TN removal efficiency decreased from 30% to 19%)when compared with the case without internal recycle. When granular sludge was formed, the internal recycle (at recycle ratio of 92%) had positive effect on TN removal (the TN removal efficiency increased from 76% to 84%).

Surface morphology of zeolite before and after modified was analyzed through the particle strength, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) and point of zero charge (pHPZC). Adsorption studies were carried out at different pH, zeolite dosage, initial ammonium concentrations and temperature. Adsorption mechanism was measured through the adsorption isotherm and adsorption dynamics. The feature of NaCl modified zeolite included increased particle strength, a rough surface, and enlarged pore size. It was also found that sodium ions would enter the zeolite internal through ion exchange. The experimental results showed that the best adsorption condition was pH value of 7, zeolite dosage of 8g/L and temperature at 35℃. The study also revealed that equilibrium adsorption capacity (qe) was positive correlation with initial ammonium concentration. Adsorption data was fitted better to Langmuir adsorption isotherms, with maximal adsorption capacity of 13.210mg/g. The results of kinetics study indicated that the pseudo-second-order model fitted to the experimental data well. These results therefore proved that NaCl modified zeolite could be effectively used as a low-cost adsorbent for the removal of ammonium from wastewater.

Sodium alginate (SA) immobilized nanoscale zero-valent iron (nZVI) was synthesized and applied to reduce the azo dye (reactive red X3B) in water. The effects of SA concentration, nZVI dosage, reactive red X3B initial concentration, temperature, and initial pH on removal efficiency were investigated, respectively. High performance liquid chromatography (HPLC), UV-vis spectrophotometer (UV-Vis), scanning electron microscopy (SEM), and transmission electron microscope (TEM) were employed to analyze the reductive decolorization process of the target pollutant by the nanocomposites. As high as 98.9% reactive red X3B were removed after 720min (T=25℃, pH=10.9, 200r/min, 2.0g/L nZVI with 2.0wt% SA loading, and 25.0mg/L X3B). The adsorption of reactive red X3B by sodium alginate gel was not observed, and the main mechanism of reactive red X3B decolorization was attributed to the reactive red X3B reduction by nZVI.

The mechanisms of partial nitrification in sequencing batch reactor was studied under the condition of AOB oxygen affinity lower than NOB by calibrating the kinetic parameters of nitrification accurately. The measured DO half saturation constants for AOB and NOB were 0.46 and 0.14mg O₂/L respectively. Under the condition, the higher AOB specific growth rate than NOB was an important feature for achieving partial nitrification. The AOB and NOB specific growth rates were measured at 0.65 and 0.45 d^-1 respectively. The two-step nitrification model simulation indicated that the low DO and high SRT (sludge retention time) conditions were detrimental for achieving partial nitrification, which could be more readily achieved under the combined condition of relative high DO and low SRT. The experimental result verified the simulation results.

The radical was formed by the carbon nanotube (CNT) activation of peroxymonosulfate (PMS). Effect of chloride ion (Cl^-) on degradation of Orange G (OG) by CNT/PMS system were investigated. Cl^- had a dual effect on OG decolorization in the CNT/PMS system. Low dosage of Cl^- could inhibit OG decolorization, whereas high dosage could promote its decolorization. Meanwhile, Cl^- could directly react with PMS alone to decolorize OG. In the CNT/PMS/Cl^- system, effect of various factors were explored, including PMS dosage, reaction temperature, initial concentration of OG, Cl^- concentration, and initial pH, and the degradation mechanism was further proposed. The results indicated that 100% decolorization of OG was observed after 25min when 1.6mmol/L of PMS, 0.08mmol/L of OG, 50mmol/L of Cl^- were present at 25℃. The activation energy of reaction system was determined to be 88.45kJ/mol. With the increasing initial pH, OG decolorization was decreased first and then gradually increased. Both of SO₄^-·and HOCl were found to be responsible for OG degradation. The mineralization rate during the degradation of OG were analyzed, and higher mineralization rate was observed when CNT was present in the system. From the analysis of UV-vis spectra and GC-MS, the azo band and naphthaline ring of OG were destroyed to generate other small intermediates.

Zeolite trickling filter (ZTF) was developed to treat domestic wastewater. Biofilm colonization and the effects of hydraulic loading rate (HLR) on the treatment of domestic wastewater by the ZTF were investigated. In biofilm colonization stage, the influent was set as the "continuous manner", and after 26d, COD and ammonia removal efficiencies reached 85% and 68%, even more, respectively, moreover, relative deviation of the two adjacent test results of COD and ammonia were less than 10% in this period, indicated that the biofilm colonization was success and the ZTF reached a stable operation state. The ZTF exhibited a strong adaptability on the variation of hydraulic loading rate (HLR), and average removal efficiencies of COD, ammonia, TN, TP reached 90.8%, 87.1%, 67.2%, and 90.1%, respectively, when the HLR was adjusted to 300L/(m²·d). In the treatment process by the ZTF, COD, ammonia, and TN could be efficiently removed, and the biological decomposition and biotransformation processes of microorganisms were the most important pathway for pollutants removal, while the adsorption of phosphorous onto the zeolite substrates could explained as the main removal mechanism, in which metal irons oxidized into ferric hydroxides was the key factor for adsorption of phosphorus. Moreover, the bacterial diversity in the ZTF was very rich, which could be proved by the characteristics of biomass and microorganism population distribution

Based on tylosin was wsed as one representative organic pollutant, the sorption characteristics and mechanism of tylosin on different sources of nano black carbon-humic acid complexes was invesitigated. Results showed that the sorption capacity of black carbon and humic acid complex was higher than that of black carbon and humic acid; the sorption equilibrium could be obttained within 24hours; the sorption kinetics of tylosin on both black carbon and black carbon-humic acid complex fitted the pseudo-second-order kinetics model; the sorption isotherms could fit well with the Henry model and Freundlich model; the sorption capacity of tylosin on black carbon and humic acid complex would be altered in different solution chemistries (i.e., pH and ionic strength of solutions). Ion-exchange, hydrogen-bond, and hydrophobic play a main role in the sorption of tylosin on black carbon and humic acid complex.

Carbon nanotube (CNT) was used as an activator to activate persulfate (PS) to decolorize the azo dye, acid orange 7 (AO7). Effect of PS dosage, CNT loading, initial pH and reaction temperature on decolorization of AO7 was investigated. The results indicated that completely decolorization of AO7 was achieved within 480min when 0.2g/L of CNT and 20 of n(PS)/n(AO7) were present in the system. AO7 decolorization was increased with increasing PS dosage, raising CNT loading and elevating temperature, and neutral pH was most favorable for AO7 decolorization. The oxidative degradation of AO7 mainly took place on the surface of CNT and the activation energy (Ea) was determined to be 46.76kJ/mol. From the analysis of UV-Vis spectra, GC-MS and TOC during the reaction, the azo band and naphthalene ring of AO7 were proposed to be destroyed to generate other small intermediate containing benzene, and finally mineralized to CO₂ and H₂O.

The inner loop continuous sand filter (ILCSF) is often used as the pretreatment process for the removal of SS and COD during the advanced treatment of biological secondary effluent. ILCSF can guarantee the operation stability of the following connected advanced treatment unit. In this study, poly aluminum chloride (PAC) and poly aluminum ferric chloride (PAFC) were used as the coagulant and the performance and operation of ILCSF were investigated. The results showed that when the dosages of PAC and PAFC ranged from 5to 30mg/L, the removal of SS and COD increased at the beginning and then decreased when the dosage was over 10mg/L. The optimized coagulant dosage was 10mg/L for PAC and PAFC. The removal rates of SS and COD were 49.7% and 12.9% for PAC and 50.6% and 13.8% for PAFC on the optimized dosage. The ILCSF could preferentially remove the macromolecular organic matters with the relative molecular weight higher than 3k. However, the ILCSF has the poor ability to remove the dissolved organic matters (DOM). The dissolved organic carbon (DOC) removal rate was lower than 5% even on the optimized conditions. The dose of PAFC was more suitable for the stable operation of ILCSF than dose of PAC. The viscosity of the mixture dosing PAFC was lower than that of dosing PAC. In this study, the optimized dosage of PAFC was determined with the value of 10to 15mg/L. It could guarantee the high removal rate of SS and the stable operation of the ILCSF.

Formation of disinfection by-products (DBPs) from chlorination of Escherichia coli, a bacterial strain which was commonly found in drinking water as a representative of aquatic microorganism, was investigated under selected conditions. Evaluated factors included contact time, chlorine dosages, pH and bacterial concentrations. These factors potentially influence the DBPs formation in the disinfection systems, which could be optimized for minimization of DBPs formation during chlorination of drinking water. Results showed that the formation of DCAN from the bacterial suspension initially increased and then decreased with increased chlorine dose. The formation of 1,1,1-TCP and DCAN followed a similar pattern of increase and then decrease with prolonged reaction time. At the same time, the concentrations of DCAA, TCAA, TCNM and 1,1,1-DCP decreased when pH was increased from 5 to 9. Bacterial contamination in aquatic environments has been extensively reported in recent years. Increased bacterial concentration in the raw water may lead to a higher formation of TCM, TCNM, DCAA and TCAA, but not for DCAN, TCAN, 1,1-DCP and 1,1,1-TCP. To achieve a low toxicity in drinking water, it is suggested from this study that chlorine concentration should be kept low, under disinfection contact time of 6h and alkaline condition (pH>8).

A new method, Numerical Source Apportionment (NSA) approach,was proposed based on the widely applied water quality model, The Environmental Fluid Dynamics Code (EFDC), to get the source component of pollutants, theoretically for any location of the lake at any time. The main idea behind was to take partial derivative of water quality equation with respect to each polluting source. After that, a set of partial differential equations were derived from one water quality partial differential equation. These equations were then solved together with hydrodynamic model in EFDC. As a result, by running model only one time, the contribution of each polluting source at each spatial and temporal point could be achieved. Generalized Lake Fuxian model was taken to validate NSA. Source apportionment results of NSA are coordinate with traditional perturbation method, which validated NSA method. On the other hand, for there were 34independent polluting source in numerical case study, to get source apportionment results traditional perturbation method had to run model for 35 times while NSA only required one time which indicated NSA has obvious advantage on computation efficiency. Further analysis showed NSA could provide more precise description on the dynamic of source apportionment.

Polyaniline and carbon nanotube composites (CNT/PANI) were synthesized through in situ chemical oxidative polymerization method, the physicochemical properties of the composites were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). Compared with the pure CNT, CNT covered by PANI had a smaller specific surface area and porosity, but had a higher specific capacitance. Experiments indicated that the removal efficiency of Cu²⁺ by CNT/PANI electrode was 4.24 times that by CNT electrode. The adsorbed amount of Cu²⁺ increased with the increase of the voltage, initial Cu²⁺ concentration and solution pH. The electrosorption of CNT/PANI electrodes for Cu²⁺ followed the pseudo-first-order kinetic model.

In order to understand the influence of nitrate (NO₃^-) photochemical activity on the phosphate released from organic phosphorus indirect photolysis degradation, the phosphate released from glyphosate photodegradation by NO₃^- was investigated in deionised and natural water under UV irradiation. Meanwhile, the methanol was used as the·OH scavenger to confirm the role of NO₃^- on the phosphate released from organic phosphorus degradation in the natural eutrophication lakes. The results showed that the phosphate could be released from glyphosate photolysis under UV irradiation and the release amount of phosphate increased with pH and initial concentration of glyphosate increasing under UV light irradiation in deionised water. NO₃^- adding enhanced the phosphate released from glyphosate photodegradation in comparison with direct photolysis and the concentration of phosphate increased from 0.05mg/L to 0.43mg/L with the 20mg/L NO₃^- added to the solution under UV irradiation for 60min. The effect of environmental parameters including Fe³⁺, HCO₃^- and humic acid on the phosphate released from glyphosate photodegradation by NO₃^- was also performed. In the presence of Fe³⁺, the amount of phosphate released from glyphosate photodegradation increased significantly due to photosensitization by reactive species such as hydroxyl radical. The presence of humic acid and HCO₃^- inhibited phosphate released through a radical scavenging effect. The release amount of phosphate in the natural water with NO₃^- spiked is higher than that of control and the phosphate released was inhibited when the methanol was added to the reaction system. All these results reveal that NO₃^- plays an important role in phosphate released from organic phosphorus photodegradation.

The catchment scale assessment of sewer defect conditions based on physical or flow inspection method is usually very labour-intensive and even hard to perform. Therefore, a novel cost-effective method to locate groundwater infiltration into the sewers and accordingly assess the sewer network defect severity was presented, using chemical markers monitoring at pipe manholes and a geographical information system that integrates sewer network and discharged destinations of sewage sources. With acesulfame as the marker of sanitary sewage, the spatial groundwater infiltration into the sewers was investigated within the 14.4km² catchment served by a wastewater treatment plant in Chaohu City, Anhui Province. Based on that, the locations of serious sewer network defect were also identified. The quantified groundwater infiltration into the sewers using marker monitoring was comparable to the data from the catchment water flow balance and measured groundwater inflow of one typical sewer segment, with a relative error of 21.0% and 5.4% respectively. This indicated the developed method was reliable. It was found that one sewer segment covering only 0.3% of the total sewer length even contributed to 23.0% of the total infiltrated groundwater within the area. From this perspective, the repair of local serious sewer defect would obviously lower the defect grade of the whole sewer network. The basic principle to perform this method was finally suggested.

Single component and competitive adsorption of p-nitrophenol (p-NP) and heavy metals on water-quenched blast furnace slag (WBFS) were investigated in this study. The adsorption isotherms, kinetics and thermodynamics were studied to explore adsorption characteristics and mechanisms. The results showed that heavy metals played a dominant role in controlling the competitive adsorption with p-NP in a sequence of Cu²⁺ > Cd²⁺ > Zn²⁺. The equilibrium data for adsorption of p-NP by WBFS could be well described by Freundlich isotherm model, while Langmuir isotherm could better fit the data for the adsorption of heavy metal ions on WBFS. The adsorption energy of p-NP calculated by D-R model in each system was -7.53, -7.07, -7.96 and -7.86kJ/mol, respectively. The results showed that WBFS adsorbed p-NP via physical adsorption, while adsorbed metal ions via chemical adsorption and ion exchange. The kinetic results demonstrated that the adsorption rate of p-NP decreased in the presence of heavy metal ions. And the corresponding time to reach adsorption equilibrium was prolonged. However, the patterns for the adsorption of heavy metal ions were not significantly influenced in the presence of p-NP. In the binary system, WBFS exhibited relative higher affinity and selectivity for Cu²⁺, Cd²⁺ and Zn²⁺ than p-NP. The adsorption data of p-NP and heavy metal ions were fitted well by the pseudo-second-order model in both single and binary systems. The values of △G decreased with increasing temperature, indicating the spontaneous nature for the adsorption of p-NP and Cu²⁺、Cd²⁺、Zn²⁺ was proportional to the temperature.The thermodynamics results also indicated the adsorption were an endothermic and entropy-increasing process.

A systemic method was developed through integrating the orthogonal experimental design,water quality model and evaluation technique.Such method can be used for identifying the optimal total emission control schemes for the Lake Dianchi Basin. Firstly, TN and TP as the evaluating indicators were designed with 5levels (i.e., 0%, 5%, 10%, 15% and 20%, respectively); meanwhile, the entire Basin was divided into 6subareas. Accordingly, the orthogonal design table (6factors and 5levels) was employed and then 25 reduction scenarios would be generated. Secondly, the TN, TP and Chl-a concentration distribution of the Lake could be simulated by the EFDC Model under different reduction scenarios. Then, we could calculate the value of Trophic State Index (TSI), and select the eligible reduction scenarios if 60

Effects of physic-chemical properties and biogas production were studied through orthogonal experiment with different hydrothermal pretreatment conditions, in the basis of the preliminary optimization of single factor test and with rice straw as raw material. The results showed that there has different impact on the 20days cumulative biogas production of anaerobic fermentation with rice straw for three factors, which including pre-leaching time and content of initial moisture with materials and heating time. The order of the effect on the cumulative TS yield of anaerobic fermentation for each factor is that content of initial moisture with materials > pre-leaching time > heating time; the condition that the initial water content of 55%, leaching time of two hours, the heating time of six hours were considered as the best condition. The 20days cumulative biogas production with rice straw under this optimum pretreatment conditions is increased by 29.79%, the time of biogas production reached 60% and 80% of the total gas production can be reduced five days compared with CK. And the result showed that the mild hydrothermal pretreatment promoting the degradation of cellulose and hemi-cellulose and make it more converted to volatile fatty acids (VFA), which is conducive to rapid biogas production of rice straw, combined with analysis of the changes of physical and chemical properties. The mild hydrothermal pretreatment process parameters that provided technical support and theoretical basis for the operation of straw biogas project were obtained from this experiment.

A novel hydrometallurgical process for recovery of palladium and gold from phone components in HCl^-CuCl₂-NaClO leaching system was offered, different factors of Pd, Au leaching process were investigated. The results of experiment indicated that, on the condition of 2mol/L HCl, 5% NaClO, 0.075mol/L CuCl₂ at 333K for 2h with a solid/liquid ratio of 1/100, over 85% of Pd and Au was leached. Cu²⁺, Cl^-, the temperature for the Pd leaching rates played a significant role. NaClO was added to solutions could accelerate the Pd leaching reaction rates; NaClO, the temperature for the Au leaching rates had a significant influence. The additions of HCl, Cu²⁺ to promotes Au leaching. Therefore, HCl^-CuCl₂-NaClO leaching system for Pd, Au leaching have a positive effect.

The predatory bacteria with high cell lysis capacity was isolated and screened from the activated sludge of a municipal wastewater treatment plant. The efficiency of sludge biolysis with an addition of the enriched predatory bacteria for enhancing its dewaterability was evaluated and the associated environmental impact factors were investigated. The results indicated that the predatory bacteria with a broad range of hosts were abundant in the municipal sewage sludge and greatly benefited sludge lysis. The concentration of the predatory bacteria enrichment could be improved with the increase of host dosage but not the concentration of the culture medium. When the neutral municipal sludge was incubated with the screened predatory microbes at the concentration of 106 pfu/mL for 24h at room temperature, the values of the specific resistance to filtration (SRF) and the volume of the treated sludge were 36% and 15% lower than the control sludge without bacteria addition, respectively. Meanwhile, the cell lysis led to the release of intracellular nutrients. The concentrations of total nitrogen (TN) and total phosphorous (TP) in the liquid phase of the treated sludge were increased by 245% and 242%, respectively and the ratio of SCOD/TCOD was increased by 195%. However, there is no positive correlation between the biolysis effect and the reaction time and the optimal sludge biolysis reaction time was 24h.

To clarify the effects of pH on propionate degradation in an anaerobic system, the degradation characteristics of a propionate enriched culture at slightly acidic conditions were investigated. Under the biomass of 0.22g MLVSS/L and initial propionate of 1000mg/L conditions, propionate was rapidly oxidized at pH7.0 (control) and propionate removal achieved 98.5% after 6days cultivation. pH decrease, from 7.0 to 6.5 and 6.0, resulted in propionate removal rate was decreased instantaneously. But propionate degradation rate was recovered to the value at pH 7.0 after 2~3 days adaptation. Propionate removal at pH 6.5 and pH 6.0 were reached above 97% after 8 days and 9 days cultivation, respectively. Propionate was hardly decomposed at pH 5.5 during the whole cultivation. During the whole experiment, no hydrogen was detected and acetate was transient accumulation in the early culture. These results indicated methanogens were more acid resistance than propionate-oxidizing bacteria.

Antimony (Ⅲ) is the unstable reduced form involved in the biogeochemical cycling of toxic metals Sb. The photooxidation of Sb(Ⅲ) by humic acids may be the important means for environmental fates of Sb(Ⅲ) in aquatic ecosystem. In this study, the kinetic characteristics for Sb(Ⅲ) oxidation in the presence of humic acids with different origins were examined under photoirradiation. The photooxidation behaviors of Sb(Ⅲ) were investigated over a wide range of DOC concentrations, initial Sb(Ⅲ) concentrations, pH values and the occurrence of competitive ions. The mechanisms for the photoxidation of Sb(Ⅲ) by humic acids were discussed. The photooxidation of Sb(Ⅲ) by humic acids followed the pseudo-first-order kinetics model. The photooxidation rate constants increased rapidly with increasing pH values and DOC concentrations in the Sb(Ⅲ)-humic acids reaction systems. However, Sb(Ⅲ) photooxidation was inhibited with increasing initial Sb(Ⅲ) concentrations. The photooxidation rate constants of Sb(Ⅲ) under the humic acids with lignite origin were higher than that with soil origin. The occurrence of anionic NO₃^- enhanced the photooxidation of Sb(Ⅲ). However, there were no obvious effects of Cl^-、SO₄^2- and Na⁺ on Sb(Ⅲ) photooxidation. The ESR spectra suggest that hydroxyl radicals and superoxide free radicals induced by light are were reactive oxidants for Sb(Ⅲ) photooxidation. Hydroxyl radicals were the primary oxidants for Sb(Ⅲ) photooxidation under the acidic condition, and superoxide free radicals became the main photo-oxidants under the neutral and alkaline condition.

The release pathway of dissolved organic matter (DOM) in sediments of the Xinkaihe River in Shenyang, as well as the effect of time, temperature, pH, sediment particle size, salinity, and dissolved organic carbon (DOC) concentration in the overlying water on the release of DOM in sediments was evaluated. In addition, the effect of release of DOM in sediments on the spectroscopy characteristics of DOM in the overlying water was also examined. The results showed that the mixing action of interstitial water had the greatest influence on the release of DOM in sediments, which was followed by the static release of surface sediment, while the release of suspended particles made slight influence on the release of DOM in sediments. The release amount of DOM in sediments increased with the increase of temperature, pH, sediment particle size, and the salinity. When the DOC concentration in the overlying water was relatively high, the DOM moved from the overlying water to the sediment. The disturbance could affect the migration of DOM in sediments. The fulvic acid- and aromatic protein-like fluorophores were dominant in fluorescent materials in DOM in sediments. The fluorescent materials with excitation wavelength of 280~300nm and 320~380nm were the main fluorescent materials which were released from the sediment to the overlying water. Moreover, the disturbance promoted the release of fluorescent materials from the sediment to the overlying water.

Sulfate-reducing bacteria (SRB) are ubiquitous and quantitatively important members in many ecosystems, especially in marine sediments. In this study, the abundance and distribution of SRB was investigated in the surface sediments from East China Sea in April, July, August and October, 2011. A quantitative polymerase chain reaction (qPCR) analysis targeted the dissimilatory sulfite reductase β subunit gene (dsrB), which encodes a key enzyme in the sulfate reduction pathway, was performed to assess the abundance of the SRB in the sediments. The abundance of SRB ranged from 1.87×105 to 4.69×108 cells per gram wet weight sediment, with the lowest and the highest value in April and July, respectively. The ratios of SRB to total bacteria varied from around 0.0039%~1.6176%, which implied that SRB constituted a very small proportion of the total bacteria. The abundance of SRB in the southern areas was higher than that in the northern areas, and the abundance of SRB in the mud area was much higher than that in the non-mud area. In addition, statistical analysis demonstrated that temperature and dissolved oxygen concentration were important factors affecting the distribution of SRB abundance. This study presented the temporal and spatial distribution characteristics of SRB abundance, providing insights into understanding the carbon and sulfur biogeochemical cycles in the surface sediments from East China Sea.

The effects of different Cu²⁺ concentrations (0.16, 0.32, 0.66, 1.16, 2.16, 4.16μmol/L) in culture media on the cell density, chlorophyll-a content and chlorophyll fluorescence parameters (CFP) of Microcystis aeruginosa within the first 120h were investigated. It shows that Cu²⁺ concentration had significant effects on the growth and chlorophyll-a content of Microcystis aeruginosa (P<0.05) from 12h to 120h by One-way ANOVA. The growth of Microcystis aeruginosa could be promoted as the Cu²⁺ concentration was between 0.32~1.16μmol/L and can be inhibited as that is below 0.16μmol/L or above 2.16μmol/L. The obvious effects on the CFPs of Fv/Fm, ΦPSⅡ and ETR were not observed when the Cu²⁺ concentration is below 2.16μmol/L. But the serious bad influences were found when the Cu²⁺ concentration was 4.16μmol/L. Its values of Fv/Fm, ΦPSⅡ and ETR were much less than that of other Cu²⁺ concentration (P<0.05), while shows the following changing trends:rapidly decreasing within the first 24h, then rapidly increasing within 24h~96h and finally slowly decreasing within 96h~120h.