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Li D.-B.,Shanghai Ocean University | Zhang W.,Shanghai Ocean University | Zhang W.,Shanghai Aquatic Environmental Engineering Co. | Wang L.-Q.,Shanghai Ocean University | And 2 more authors.
Journal of Ecology and Rural Environment | Year: 2014

Spectral absorption characteristics, distribution and potential sources of CDOM (chromophoric dissolved organic matter) in 14 rivers running in 6 districts of Shanghai were investigated in August 2013. Results show that spectral absorption coefficients of CDOM in the rivers, regardless of districts, all displayed an exponentially decreasing trend in all bands from ultraviolet to visible light with CDOM spectral absorption coefficient a (355) varying in the range of 2.34-4.33 m-1. Spectral absorption coefficient of CDOM in rivers varied sharply from district to district. On the whole, CDOM spectral absorption coefficient was higher in rivers running in the urban area than in rivers in the suburban area. Correlation analysis reveals that, CDOM spectral absorption coefficient a (355) was closely related to permanganate index and turbidity, separately, but not so much to concentration of chlorophyll a (average 30.59 μg · L-1), which suggests that the CDOM in the rivers may mainly come from the terrestrial sources, such as urban domestic sewages, industrial wastewater, agricultural non-point source pollution, etc. Analysis of M, ratio of a(250)/a(365), and S, spectral absorption slope, brought about the same conclusion. The study of CDOM optical properties in the river water of Shanghai would help understand distribution of underwater light field in the rivers of Shanghai, and lay down some theoretical basis for restoration of aquatic vegetations in the rivers. Source

Ma W.-H.,Shanghai Ocean University | Zhang W.,Shanghai Ocean University | Zhang W.,Shanghai Aquatic Environmental Engineering Co. | Gu W.-W.,Shanghai Ocean University | And 2 more authors.
Huanjing Kexue/Environmental Science | Year: 2014

The community structures of rotifers were surveyed in Lin'gang B Gang River, a new estuarial river in Shanghai, from December 2011 to November 2012. A total of 23 rotifer species were identified, of which 19 species were the indicator of environmental pollution. Rotifer species' number rose monthly from 2 to 13. A conspicuous succession of dominant species was observed from a single dominant species (Keratella cochlearis) to several species. The rotifer community structure of Lin'gang B Gang River differs with that of the outer water body (Lu Chaoyin River). Pearson analysis showed that the rotifers' density had a significant correlation with water temperature and chlorophyll-a (P<0.05), but had no significant correlation with salinity; the densities of dominant species (except Keratella cochlearis) presented negatively correlations with concentration of nutrients and salinity (P<0.05). The low species similarity index between every month demonstrated that aquatic ecosystem of Lin'gang B Gang River was in the unstable state. However, the increase of Margalef index and Shannon-Wiener index of rotifers and the decline of E/O value monthly showed the water environment of Lin'gang B Gang. River was improved. Source

Xu Y.-P.,Shanghai Ocean University | Liu C.-H.,Shanghai Ocean University | Zhang Y.-Y.,HIGH-TECH | Zhang W.,Shanghai Ocean University | And 4 more authors.
Chinese Journal of Ecology | Year: 2014

To explore the phytoplankton community structure and its relationship with environmental factors, a survey was conducted in the newly excavated landscape river (Port B, Lingang, Shanghai) from December 2011 to November 2012. The results showed that there were 223 phytoplankton species, which belong to seven Phyla. Phyla Chlorophyta had the most species, followed by Cyanophyta and Bacillariophyta. The phytoplankton abundance ranged from 7. 52×106 to 212×106 cells · L-1, with an average of 66. 27×106 cells · L-1. The species abundance in the rainy period was significantly higher than in the drought period, while cell density was vice versa. The dominant species was simplex for each season, which mainly consisted of the Merismopedia spp. Canonical correspondence analysis (CCA) showed that the distribution of phytoplankton in the four quadrants was homogeneous, which reflected the typical characters of sub-tropical climate. PCA and CCA indicated that salinity and nutrients (TN and TP) were the main driving factors for the dynamic change of phytoplankton community. Chroococcus minor, Merismopedia glauca, Tetraedron tumidulum and Synedra sp. could be used as efficient indicators for salinity, while Fragilaria brevistriata, Synedra acus, Ntizschia closterium and Chroococcus tenax showed a potential value for indicating the organic pollution. © 2014, Editorial Board of Chinese Journal of Ecology. All rights reserved. Source

Xu H.,Shanghai Ocean University | Zhao F.,Shanghai Ocean University | Zhang W.,Shanghai Ocean University | Zhang W.,Shanghai Aquatic Environmental Engineering Co. | And 2 more authors.
Chinese Journal of Environmental Engineering | Year: 2015

To supervise the optimal ecological management mode of urban artificial lakes, aquatic ecosystem among artificial Lake Jincheng No.2 of Chengdu City is constituted on the basis of biological manipulation theory. Subsequently, water quality and the succession of aquatic macrophytes community in Lake Jincheng No.2 were tracked and investigated to assess the effort of ecological management. The results illustrated that, this ecological restoration technique, building the various aquatic-trophic levels artificially, was an effective treatment process for improving water quality in Lake Jincheng No.2. The amount of nitrogen and phosphorus removed by the water treatment process were reached up to 7.28 t and 0.25 t, respectively, in the duration of the first year management. The Secchi disc depth was maintained at a high level. No water-bloom was observed during the first year. The amount of nitrogen and phosphorus were removed 5.6 t and 0.29 t, respectively during January to July in the following year. Nevertheless, the relentlessly deteriorated water quality and aquatic ecosystem attribute to highly polluting water drains into the lake and remaining man-made impacts. Overall, our research enlarges the horizon of related studies as the reference of the similar ecological management project. ©, 2015, Science Press. All right reserved. Source

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