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The performance of an integrated process including coagulation, ozonation, ceramic ultrafiltration （UF） and biologic activated carbon （BAC） filtration was investigated for the removal of organic matter and disinfection by-products （DBPs） precursors from micropolluted surface water. A pilot scale plant with the capacity of 120 m3 per day was set up and operated for the treatment of drinking water. Ceramic membranes were used with the filtration area of 50 m2 and a pore size of 60 nm. Dissolved organic matter was divided into five fractions including hydrophobic acid （HoA）, base （HOB） and neutral （HoN）, weakly hydrophobic acid （WHOA） and hydrophilic matter （HIM） by DAX-8 and XAD-4 resins. The experiment results showed that the removal of organic matter was significantly improved with ozonation in advance. In sum, the integrated process removed 73% of dissolved organic carbon （DOC）, 87% of UV254, 77% of trihalomethane （THMs） precursors, 76% of haloacetic acid （HAAs） precursors, 83%of trichloracetic aldehyde （CH） precursor, 77% of dichloroaeetonitrile （DCAN） precursor, 51% of trichloroacetonitrile （TCAN） precursor, 96% of 1,1,1- trichloroacetone （TCP） precursor and 63% of trichloroni- tromethane （TCNM） precursor. Hydrophobic organic matter was converted into hydrophilic organic matter during ozonation/UF, while the organic matter with molecular weight of 1000-3000 Da was remarkably decreased and converted into lower molecular weight organic matter ranged from 200-500 Da. DOC had a close linear relationship with the formation potential of DBPs.

Rapid monitoring of water quality is crucial to the operation of municipal wastewater treatment plants （WWTPs）. Fluorescence excitation-emission matrix （EEM） in combination with parallel lhctor analysis （PARAFAC） has been used as a powerful tool for the characterization of dissolved organic matter （DOM） in WWTPs. However, a recent work has revealed the drawback of PARAFAC analysis, i.e., overestimating the component number. A novel method, parallel lhctor framework-clustering analysis （PFFCA）,＂has been cleveloped in our earlier work to resolve this drawback of PARAFAC. In the present work, both PARAFAC and PFFCA were used to analyze the EEMs of water samples from a full-scale WWTP from a practical application point of view. The component number and goodness-of- fit from these two methods were compared and the relationship between the relative score change of component and the actual concentration was investigated to evaluate the estimation error introduced by 9 both methods. PFFCA score and actual concentration exhibited a higher correlation coefficient （R- = 0.870） compared with PARAFAC （R2〈 0.771）, indicating that PFFCA provided a more accurate relative change estimation than PARAFAC. The results suggest that use of PARAFAC may cause confusion in selecting the component number, while EEM-PFFCA is a more reliable alternative approach for monitoring water quality in WWTPs.

This study examined the spatiotemporal dynamics of colored dissolved organic matter （CDOM） and spectral slope （S）, and further to analyze its sources in three productive water supplies （Eagle Creek, Geist and Morse reservoirs） from Indiana, USA. The re- sults showed that he absorption coefficient aCDOM（440） ranged from 0.37 m-1 to 3.93 m-1 with an average of 1.89 ± 0.76 m-1 （±SD） for the aggregated dataset, and S varied from 0.0048 nm -1 to 0.0239 nm-1 with an average of 0.0108 ±0.0040 nmI. A significant relation- ship between S and aCDOM（440） can be fitted with a power equation （S = 0.013 × aCDOM（440）-0.42, R2 = 0.612）, excluding data from Geist Reservoir during high flow （12 April 2010） and the Morse Reservoir on 25 June 2010 due to a T-storm achieves even higher determina- tion coefficient （R2 = 0.842）. Correlation analysis indicated that aCDOM（440） has strong association with inorganic suspended matter （ISM） concentration （0.231 〈 R2 〈 0.786） for each of the field surveys, and this trend followed the aggregated datasets （R2 = 0.447, p 〈 0.001）. In contrast, chlorophyll-a was only correlated with aCDOM（440） in summer and autumn （0.081 〈 R2 〈 0.763）, indicating that CDOM is mainly from terrigenous sources in early spring and that phytoplankton contributed during the algal blooming season. The S value was used to characterize CDOM origin. The results indicate that the CDOM source is mainly controlled by hydrological varia- tions, while phytoplankton originated organic matter also closely linked with CDOM dynamics in three productive reservoirs.

Water samples were taken from Lake Dianchi, on the Yungui Plateau of southwest China, and experiments were conducted to simulate the photochemical degradation characteristic of chromophoric dissolved organic matter (CDOM) in the lake water. Three groups of experiments under different light conditions: ultraviolet (UV) light, visible light, and dark, were done and variations of fluorescence properties, UV absorbance, and dissolved organic carbon (DOC) concentrations during the experiments were analyzed to study the photodegradation process of CDOM with time. The result showed that light irradiation led to significant photochemical degradation of CDOM, resulting in changes in florescent properties, absorbance losses, decreases in aromaticity and average molecular weight, as well as decline in DOC concentration in the water. It was also observed that UV irradiation had greater effect than visible light did. However, various fluorophores had different sensitivities to the same irradiation condition, that is, protein — like fluorophore at the low excitation wavelengths is more sensitive to UV irradiation than the other fluorophores, and is more readily to undergo photo — degradation. In addition, visible light irradiation did not have significant impact on DOC in the water, with DOC concentration decrease by 5.57%–59.9% during the experiment time. These results may provide new knowledge on the environment behavior of CDOM in the water of Lake Dianchi.

Dissolved organic matter （DOM） plays an important role in heavy metal speciation and distribution in the aquatic environment especially for eutrophic lakes which have higher DOM concentration. Taihu Lake is the third largest freshwater and a high eutrophic lake in the downstream of the Yangtze River, China. In the lake, frequent breakout of algae blooms greatly increased the concentration of different organic matters in the lake sediment. In this study, sediment samples were collected from various part of Taihu Lake to explore the spatial difference in the binding potential of DOM with Cu. The titration experiment was adopted to quantitatively characterize the interaction between Cu（II） and DOM extracted from Taihu Lake sediments using ion selective electrode （ISE） and fluorescence quenching technology. The ISE results showed that the exogenous DOM had higher binding ability than endogenous DOM, and DOM derived from aquatic macrophytes had a higher binding ability than that derived from algae. The fluorescence quenching results indicated that humic substances played a key role in the complexation between DOM and Cu（II） in the lake. However, because of the frequent breakout of algae blooms, protein-like matters are also main component like hnmic matters in Taihu Lake. Therefore, the metals bound by protein-like substances should be caused concern as protein-like substances in DOM were unstable and they will release bound metal when decomposed.

Samples of chromophoric dissolved organic matter （CDOM） in the East China Sea in autumn （October in 2011） were analyzed by excitation emission matrix （EEM） fluorescence spectroscopy combined with parallel factor analysis （PARAFAC）. Three terrestrial humic-like components （C1, C2 and C3） and one protein-like component （C4） were identified. Based on spatial dis- tributions, as well as relationships with salinity, the following assignments were made. The three humic-like components （CI, C2 and C3） showed conservative mixing behavior and came mainly from riverine input. The protein-like component （C4） was considered a combination of autochthonous production and terrestrial inputs and a biologically labile component. Path analysis of samples from the middle and bottom layers revealed that the causal effects on C1 were -78.46% for salinity, and -21.54% for apparent oxygen utilization （AOU）; those on C2 were -76.43% for salinity, and -23.57% for AOU; those on C3 were -70.49% for salinity, 7.01% for Chl-a, and -22.50% for AOU; those on C4 were -55.54% for salinity, 14.6% for Chl-a, and -29.86% for AOU in middle layer; and those on C4 were -57.37% for salinity, 29.02% for Chl-a, and -13.61% for AOU in bottom layer. Results indicated that CDOM in tile East China Sea was mainly affected by terrestrial inputs, and microbial ac- tivities also played a key role in biogeochemical processes of CDOM. The application of the EEM-PARAFAC model present- ed a unique opportunity to observe compositional changes in CDOM in the East China Sea. In addition, the humification index （HIX） suggested that CDOM from the East China Sea was less stable and stayed shorter in the environment.

The distribution and chemical properties of chromophoric dissolved organic matter （CDOM） in the Jiaozhou Bay, China were examined during four cruises in 2010-2011. The influence of freshwater and industrial and municipal sewage along the eastern coast of the bay was clearly evident as CDOM level- s （defined as a30s）, and dissolved organic carbon （DOC） concentrations were well correlated with salinity during all the cruises. Moreover, DOC concentrations were significantly correlated with chlorophyll a con- centrations in the surface microlayer as well as in the subsurface water. The concentrations of DOC and CDOM displayed a gradually decreasing trend from the northwestern and eastern coast to the central hay, and the values and gradients of their concentrations on the eastern coast were generally higher than those on the western coast. In addition, CDOM and DOC levels were generally higher in the surface microlayer than in the subsurface water. In comparison with DOC, CDOM exhibited a greater extent of enrichment in the microlayer in each cruise, with average enrichment factor （EF） values of 1.38 and 1.84, respectively. Four fluorescent components were identified from the surface microlayer and subsurface water samples and could be distinguished as peak A, peak T, peak B and peak M. For all the cruises, peak A levels were higher in the surface microlayer than in the subsurface water. This pattern of variation might be attributed to the terrestrial input.

The retrieval of dissolved organic carbon （DOC） distribution by remote sensing is mainly based on the em- pirical relationship of DOC concentration and colored dissolved organic matter （CDOM） concentration in many literatures. To investigate the nature of this relationship, the distributions and mixing behaviors of DOC and CDOM are reviewed in the world＇s major estuaries and bays. It is found that, generally, the C- DOM concentration is well correlated with the salinity in most estuaries, while DOC usually shows a non- conservative behavior which leads to a weak correlation between the DOC concentration and the CDOM concentration. To establish a good satellite reversion of the DOC concentration, the East China Sea（ECS） was taken as an example, and the mixing behavior of DOC and CDOM as well as the influence of biogeo- chemical processes were analyzed except for the physical mixing process with the data from late autumn （November, 2010） and winter （December, 2009） cruises. In the two ECS cruises, the CDOM concentration was found to be tightly correlated with the salinity, influenced little by the photochemical or biological pro- cesses. The data from the winter cruise show that DOC followed a conservative mixing along the salinity gradient, while in the late autumn cruise it was significantly affected by the biological activities, resulting in a poor correlation between the DOC and the CDOM. Accordingly, an improved DOC algorithm （CSDM） was proposed： when the biological influence was significant （Chl a greater than 0.8 μg/dm3）, DOC was retrieved by the conservative and biological model, and if the conservative mixing was dominant （Chl a less than 0.8 μg/dm3）, the direct DOC concentration and CDOM concentration relationship was used. Based on the pro- posed algorithm, a reasonable DOC distribution for the ECS from satellite was obtained in this study, and the proposed method can be applied to the other large river-dominant marginal sea.

Carbon monoxide （CO） plays a significant role in global warming and atmospheric chemistry. Global oceans are net natural sources of atmospheric CO. CO at surface ocean is primarily produced from the photochemical degradation of chromophoric dissolved organic matter （CDOM）. In this study, the effects of photobleaching, temperature and the origin （terrestrial or marine） of CDOM on the apparent quantum yields （AQY） of CO were studied for seawater samples collected from Jiaozhou Bay. Our results demonstrat that photobleaching, temperature and the origin of CDOM strongly affected the efficiency of CO photoproduction. The concentration, absorbance and fluorescence of CDOM exponentially decreased with increasing light dose. Terrestrial riverine organic matter could be more prone to photodegradation than the marine algae-derived one. The relationships between CO AQY and the dis-solved organic carbon-specific absorption coefficient at 254 nm for the photobleaching study were nonlinear, whereas those of the original samples were strongly linear. This suggests that：1） terrestrial riverine CDOM was more efficient than marine algae-derived CDOM for CO photoproduction;2） aromatic and olefinic moieties of the CDOM pool were affected more strongly by degradation processes than by aliphatic ones. Water temperature and the origin of CDOM strongly affected the efficiency of CO photoproduction. The photoproduction rate of CO in autumn was estimated to be 31.98μmol m-2 d-1 and the total DOC photomineralization was equivalent to 3.25%-6.35%of primary production in Jiaozhou Bay. Our results indicate that CO photochemistry in coastal areas is important for oceanic carbon cycle.

The formation of cancinogenic nitrosamines, esp. N-nitrosodimethylamine （NDMA） in water and wastewater treatment plants has drawn much attention in recent years. Dissolved organic matter from the transported Luan River water as water source of Tianjin was fractionated with different XAD resins and a series of ultra-filtration membranes with molecular weight （MW） cut-offs of 5k Da, 3k Da, and lk Da, respectively. The NDMA yields from the raw water and each fraction were measured to investigate their role in NDMA yield. Results indicated that the hydrophilic fraction had a higher NDMA yield than those of hydrophobic fraction and transphilic fraction. The fraction with MW below lk Da had a higher NDMA yield than that with larger MW. NDMA formation increased as the dissolved organic carbon （DOC） to dissolved organic nitrogen （DON） ratio decreased, which indicated that DON might serve as the real important precursor for NDMA. The correlation between NDMA yield and specific ultraviolet absorbance at 254nm （SUVA254） suggested that the latter might not represent the specific precursors for NDMA in the water. Besides the water quality, the influences of pH, disinfectant dosage, and disinfection contact time on the formation of NDMA were also examined. These results will help water treatment plants establish measures to control this harmful disinfection by-product.