| The Songhua River lies in the North-east China and is the biggest tributary for the boundary river between China and Russia. Phenolic pollutants in Songhua River attained much more concern to both sides. We selected nine kinds of phenolic pollutants conducted the monitoring of river section, laboratory experiments and numeric simulation to examine the characteristics of spatial-temporal distribution and the transformation-transportation processes of these pollutants in the aquatic environment. The main conclusions of this dissertation are:There was a distinct change in the contents of among the sampling period, the concentrations of January (2007), February (2007), May (2007), August (2007), January (2008) and March (2009) varied between 0.05 and 2.82, 0.04 and 2.95, 0.02 and 2.2, 0 and 0.06, 0.02-1.52 and 0.02-0.75μg/L, respectively. The concentration of phenolic pollutants in the downstream and midstream of Songhua River were higher than that of in the upstream. Based on the average detection frequency, the common phenolic pollutants in the Songhua River were selected: phenol, Nitrophenol, Chlorophenol and Methyphenol. The dominant phenolic pollutants in different hydrological period in the present study were different, in which Methyphenol in low-flow period in 2007, Chlorophenol in mean-flow period in 2007, Nitrophenol in high-flow period in 2007, low-flow period in 2008 and low-flow period in 2009. When we compared the monitoring concentration of phenolic pollutants with the water quality criteria for phenolic pollutants of the China, USEPA and Russian, we found that only 2, 4, 6-Trichlorophenol exceeds the quality criteria of USEPA and Russian on two monitoring streams (the upstream of Mudanjiang inlet and the downstream of Jiamusi) at different sampling period.The transformation-transportation processes of three selected phenolic pollutants (2, 4-Dichlorophenol, 2, 4-Dinitrophenol and 2, 4-Dimethyphenol) in the Songhua River, including sorption on sediment, biodegradation and photo-degradation, were investigated in laboratory experiments. Results indicated that (1) Environmental factors (pH value, ionic strength and temperature), the organic matter of sediment and coexisted pollutants (heavy metal, surfactants and coexisting pollutants) can affect the adsorption of three selected phenolic pollutants on sediment. Sorption equilibrium of three phenolic pollutants was achieved in 48.0 h. Pseudo-second-order and intra-particle diffusion model were well fiited to model the kinetics of the whole sorption and initial sorption process, respectively. The thermodynamic analysis indicates that the sorption is spontaneous and endothermic. The results of batch sunlight photolysis experiments, the photodegraded order of three selected phenolic pollutants were different at different hydrological period.In this study, the transformation and transportation of phenolic pollutants in the Songhua River was modelling by WASP (Water Quality Analysis Simulation Program) model. The concentration of phenolic pollutants in Zhaoyuan reach of Songhua River as the boundary conditions, modelling the concentration variation of Zhaoyuan and ZhushunTun reach of the pollutant concentrations, model predictions for the water column generally agreed with the measured values in my research for the Songhua River. After the kinetic model and data analysis, we found that the negative correlation between photolysis and flow rate (water depth); with the increasing of water temperature, the efficiency of biodegradation was increased. In contrast, the dilution of water flow was more significant, especially in the high flow period, with the increasing of flow rate, the transmission of flow will accelerate the downward passage of pollutants. The different between the modelling value and actual monitoring value can be explained by the intensity variation of point source.These research findings are of importance to an assessment of the transformation of phenolic pollutants in acquatic environemtal.
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