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Chai X.,Zhejiang University | Hu B.,Zhejiang University | Wei N.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | Mu Q.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | And 2 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2015

The spatial and temporal distribution characteristics and mechanisms, as well as the sources and potential ecological risks of heavy metals (Cu, Zn, Pb, Cd, Hg, and As) in surface sediments were analyzed based on the data obtained from Hangzhou Bay and its adjacent waters in spring from 1996 to 2012.The results show that: (1)Cu, Pb, Zn, Cd, and As presented similar overall spatial distribution patterns though differed in smaller scales, with concentrations peaked around Nanhuizui waters and decreased along north-east and south-west directions, while Hg concentrated in southeast waters of Zhoushan, instead of the southern branch of Yangtze River Estuary or northern Hangzhou Bay waters. (2) The temporal variation of heavy metals displays different patterns, i.e., Pb concentration kept rising on the whole scale, and overall concentrations of Cu, Zn, and As increased during 2001-2009 and then decreased since 2009, whereas Cd and Hg remained relatively stable with slight fluctuations during the studied period. (3)The environmental background values were 20.6, 21.0, 80.5, 0.102, 0.039, and 9.99 mg·kg-1 for Cu, Pb, Zn, Cd, Hg, and As concentrations, respectively, which were assumed based on mathematical statistics methods according to the historical records. (4)The heavy metal elements were significantly correlated (p<0.05 or even 0.01), suggesting possibly similar sources. And transport of terrigenous clastic particles was a decisive determinant of composition and distribution, while transition mechanisms of heavy metals in different substrates and pollution of marine aquaculture were also important contributors to the sources of heavy metals in this area, based on the principal components analysis. (5)The overall potential ecological risk level was moderate, with Hg and Cd being the prominent proportions of which Hg showed the level of potential risk as strong. The relatively high values of potential ecological risk index were determined in the surface sediments of Zhoushan southeast waters, southern branch of Yangtze River Estuary, and northern waters of Hangzhou Bay. © 2015, Science Press. All right reserved.


Liu L.,Chinese Research Academy of Environmental Sciences | Zheng B.,Chinese Research Academy of Environmental Sciences | Meng W.,Chinese Research Academy of Environmental Sciences | Tang J.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | And 2 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2011

Sub-areas compartmentalization of estuary is not only the precondition for developing nutrient criteria, but also the most effective tool for management of estuarine resources. It is an important step in addressing the problem of resource degradation caused particularly by nutrient overenrichment. Sub-areas compartmentalization should reduce variability of ecosystem-related measures within identified classes and maximize variability in interclass. The compartmentalization should be completely based on physical and hydrothermal parameters such as salinity gradient, excluding chemical and nutrient elements. In addition, there should be a distinct boundary between any two sub-areas, one sub-area should be a continuous geographical area. In the present study, Changjiang Estuary are carved up into sub-areas, based on the monitoring data during 2005 2006, and global relevant research results, as well as the current environmental conditions. The "United States Environmental Protection Agency Nutrient Criteria Technical Guidance Manual: Estuarine and Coastal Marine Waters and European Commission Water Framework Directive" is referred, the hierarchical classification method is performed in the study. The results show that: (1) at first class of compartmentalization, Changjiang Estuary can be compartmentalized into transitional sub-area and coastal sub-area; (2) the coastal sub-area is a very extensive range area, with great transformations in hydrological conditions, biological communities and their different responses to environmental stress, this sub-area can be divided further into three sub-areas at the second class of compartmentalization, according to the hydrological and geographical characteristics, as well as the convenience for administrative management of the sub-areas, the three sub-areas are coastal zone outside of the estuary, Hangzhou Bay and Zhoushan Archipelago. Consequently, Changjiang estuary is divided into four sea sub-areas: transitional zone, coastal zone outside of the estuary, Hangzhou Bay and Zhoushan Archipelago. In the previous compartmentalization of the Changjiang Estuary based on the characteristics of surface sediment distribution, neither the insular effects from Zhoushan Archipelago to the environment of the estuary, nor the range sizes of the archipelago and Hangzhou Bay were considered. In the present research, the compartmentalization is based on the natural geographical characteristics, the administrative districts, the features of different biota, as well as the effects of marine currents in Zhoushan Archipelago. The bifurcate river channel section of Changjiang Estuary with alternated shoals and troughs is cognized as transitional sub-area of Changjiang Estuary, the Hangzhou Bay and Zhoushan Archipelago are treated as independent sub-areas. Comparing with the previous compartmentalization of the estuary based on the nutrient distribution which reflects the differences of hydrological, chemical, and hydrodynamic elements of the estuary, the present compartmentalization using hierarchical method reflects more natural geographical characteristics of the four sea sub-areas than the previous study. The boundary between any sub-areas has definite geographical importance. The administrative units to which the sub-areas belonging are clear to different administrative districts, so that avoid managing disorder or omission. The characteristics of sea water and sediment of the four sub-areas are tested by one-way Analysis of Variance (ANOVA). The results show that there were significant differences of the characteristics among the sub-areas. In conclusion, the present compartmentalization of the Changjiang Estuary is rational. It should be helpful for normalizing human exploitation activities, the conservation of marine resources and the improvement of regional ecological environment. However, because of the complexity of the environment in Changjiang Estuary and its adjacent waters, and the increasing of human activities in the area, the compartmentalization of the estuary should be improved continuously.


Liu L.,Chinese Research Academy of Environmental Sciences | Zhou J.,Chinese Research Academy of Environmental Sciences | Zheng B.,Chinese Research Academy of Environmental Sciences | Cai W.,Chinese Research Academy of Environmental Sciences | And 3 more authors.
Marine Pollution Bulletin | Year: 2013

Between 1972 and 2009, evidence of red tide outbreaks in the Yangtze River Estuary and adjacent waters was collected. A geographic information system (GIS) was used to analyze the temporal and spatial distribution of these red tides, and it was subsequently used to map the distribution of these events. The results show that the following findings. (1) There were three red tide-prone areas: outside the Yangtze River Estuary and the eastern coast of Sheshan, the Huaniaoshan-Shengshan-Gouqi waters, and the Zhoushan areas and eastern coast of Zhujiajian. In these areas, red tides occurred 174 total times, 25 of which were larger than 1000 km2 in areal extent. After 2000, the frequency of red tide outbreaks increased significantly. (2) During the months of May and June, the red tide occurrence in these areas was 51% and 20%, respectively. (3) Outbreaks of the dominant red tide plankton species Prorocentrum dong-haiense, Skeletonema costatum, Prorocentrum dantatum, and Noctiluca scientillan occurred 38, 35, 15, and 10 times, respectively, during the study interval. © 2013 Elsevier Ltd.


PubMed | Peking University and Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station
Type: Journal Article | Journal: Marine pollution bulletin | Year: 2016

Disposal of wastewater treatment plant (WWTP) effluent into sea, a typical anthropogenic disturbance, may influence many environmental factors and change the coastal microbial community structure. In this study, by setting up coastal sediment microcosms perturbed by WWTP effluent, the changes of microbial community structure under different degree of disturbances were investigated. Quantitative PCR (qPCR) and terminal restriction fragment length polymorphism (T-RFLP) were used to analyzed the biomass and biodiversity. High throughput sequencing analysis was used to identify the classification of the microorganisms. Our study suggested that low ratio of WWTP effluent may stimulate dominant species, which increase the biomass but decrease the biodiversity; while high ratio of WWTP effluent may depress all species, which decrease the biomass but increase the biodiversity. In other words, the impact was dose-dependent. The changes of microbial community structure may provide a metric for water environmental assessment and pollution control.


PubMed | Tsinghua University, CAS Research Center for Eco Environmental Sciences, Peking University and Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station
Type: Journal Article | Journal: FEMS microbiology ecology | Year: 2016

Coastal areas are land-sea transitional zones with complex natural and anthropogenic disturbances. Microorganisms in coastal sediments adapt to such disturbances both individually and as a community. The microbial community structure changes spatially and temporally under environmental stress. In this study, we investigated the microbial community structure in the sediments of Hangzhou Bay, a seriously polluted bay in China. In order to identify the roles and contribution of all microbial taxa, we set thresholds as 0.1% for rare taxa and 1% for abundant taxa, and classified all operational taxonomic units into six exclusive categories based on their abundance. The results showed that the key taxa in differentiating the communities are abundant taxa (AT), conditionally abundant taxa (CAT), and conditionally rare or abundant taxa (CRAT). A large population in conditionally rare taxa (CRT) made this category collectively significant in differentiating the communities. Both bacteria and archaea demonstrated a distance decay pattern of community similarity in the bay, and this pattern was strengthened by rare taxa, CRT and CRAT, but weakened by AT and CAT. This implied that the low abundance taxa were more deterministically distributed, while the high abundance taxa were more ubiquitously distributed.


Jiang R.,Zhejiang Ocean University | Wang J.-X.,Zhejiang Ocean University | Huang B.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | Yu K.-C.,Zhejiang Ocean University | And 3 more authors.
Marine Pollution Bulletin | Year: 2016

The aim of this study was to investigate the bacterial community composition, the concentration of organic contaminants, and their relationship in the sediments of Jiaojiang estuary. Sediments were collected from seven stations and the environmental parameters were analyzed. The results showed that the site closest to the chemical industry zone was the most polluted. Bacterial communities were determined using 16S rRNA clone libraries and phylogenetic analysis. These results revealed that there were 13 known bacterial phyla in the sediments and that Proteobacteria were the dominant group. Using these data, we assessed the correlation between bacterial communities and organic contaminants using cluster, multidimensional scaling, and redundancy analyses. These showed that there was no simple relationship between organic contaminants and bacterial community diversity in the sediments, but polycyclic aromatic hydrocarbons were more influential than the other pollutants and negatively affected Chloroflexi. © 2016 Elsevier Ltd


PubMed | Zhejiang Ocean University and Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station
Type: Journal Article | Journal: Marine pollution bulletin | Year: 2016

The aim of this study was to investigate the bacterial community composition, the concentration of organic contaminants, and their relationship in the sediments of Jiaojiang estuary. Sediments were collected from seven stations and the environmental parameters were analyzed. The results showed that the site closest to the chemical industry zone was the most polluted. Bacterial communities were determined using 16S rRNA clone libraries and phylogenetic analysis. These results revealed that there were 13 known bacterial phyla in the sediments and that Proteobacteria were the dominant group. Using these data, we assessed the correlation between bacterial communities and organic contaminants using cluster, multidimensional scaling, and redundancy analyses. These showed that there was no simple relationship between organic contaminants and bacterial community diversity in the sediments, but polycyclic aromatic hydrocarbons were more influential than the other pollutants and negatively affected Chloroflexi.


Liu L.-S.,Chinese Research Academy of Environmental Sciences | Li Z.-C.,Chinese Research Academy of Environmental Sciences | Zhou J.,Chinese Research Academy of Environmental Sciences | Zheng B.-H.,Chinese Research Academy of Environmental Sciences | Tang J.-L.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station
Huanjing Kexue/Environmental Science | Year: 2011

The events of red tide were collected in Yangtze River Estuary and adjacent waters from 1972 to 2009. Based on geographic information system (GIS) analysis on the temporal and spatial distribution of red tide, the distribution map was generated accordingly. The results show: (1) There are three red tide-prone areas, which are outside the Yangtze River estuary and the eastern of Sheshan, Huaniaoshan-Shengshan-Gouqi, Zhoushan and the eastern of Zhujiajian. The red tide occurred 174 times in total, in which there were 25 times covered the area was larger than 1000 km 2. After 2000, the frequency of red tide were significantly increasing; (2) The frequent occurrence of red tide was in May (51% of total occurrence) and June (20% of total occurrence); (3) In all of the red tide plankton, the dominant species were Prorocentrum danghaiense, Skeletonema costatum, Prorocentrum dantatum, Nactiluca scientillans. The red tides caused by these species were 38, 35, 15, 10 times separately.


Hu X.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | Su R.,Ocean University of China | Zou W.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | Ren S.,Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station | And 3 more authors.
Acta Oceanologica Sinica | Year: 2010

The excitation spectra of chlorophyll (Chl) fluorescence can be used to differentiate phytoplankton populations at phylum level in vivo and in situ within a few minutes. The investigated phytoplankton divisions (Dinophyta, Bacillariophyta, Chrysophyta, Cyanophyta, Cryptophyta, Chlorophyta) are each characterized by a specific composition of photosynthetic antenna pigments and, consequently, by a specific excitation spectrum of the Chl fluorescence. Norm excitation spectra (emission of 680 nm and excitation of 400-600 nm) of every division were obtained from several species per division by a F4500 fluorescence spectrophotometer. Fisher's linear discriminant analysis of the norm spectra shows that the divisions could be discriminated. The discrimination method, established by multivariate linear regression and weighted least squares, was used to differentiate the phytoplankton samples cultured in the laboratory and samples collected from the Jiaozhao Bay at division level. The correctly discriminated samples were more than 94% for single algal species ones, more than 84% for simulatively mixed ones, more than 83% for real mixed ones and 100% for samples collected from the Jiaozhou Bay for the dominant species. The method for phytoplankton differentiation described here can be applied to routine checking by fluorescence spectrophotometer, and benefit the monitoring and supervision tasks related to phytoplankton populations in the marine environments. © 2010 The Chinese Society of Oceanography and Springer-Verlag Berlin Heidelberg.


PubMed | Zhejiang Provincial Zhoushan Marine Ecological Environmental Monitoring Station and Zhejiang University
Type: Journal Article | Journal: Applied microbiology and biotechnology | Year: 2016

In the current study, we investigated nitrite-dependent anaerobic methane oxidation (N-DAMO) as a potential methane sink in the Hangzhou Bay and the adjacent Zhoushan sea area. The potential activity of the N-DAMO process was primarily observed in Hangzhou Bay by means of (13)C-labeling experiments, whereas very low or no potential N-DAMO activity could be detected in the Zhoushan sea area. The measured potential N-DAMO rates ranged from 0.2 to 1.3nmol (13)CO2g(-1) (dry sediment)day(-1), and the N-DAMO potentially contributed 2.0-9.4% to the total microbial methane oxidation in the examined sediments. This indicated that the N-DAMO process may be an alternative pathway in the coastal methane cycle. Phylogenetic analyses confirmed the presence of Candidatus Methylomirabilis oxyfera-like bacteria in all the examined sediments, while the group A members (the dominant bacteria responsible for N-DAMO) were found mainly in Hangzhou Bay. Quantitative PCR showed that the 16S rRNA gene abundance of Candidatus M. oxyfera-like bacteria varied from 5.410(6) to 5.010(7) copiesg(-1) (dry sediment), with a higher abundance observed in Hangzhou Bay. In addition, the overlying water NO3 (-) concentration and salinity were identified as the most important factors influencing the abundance and potential activity of Candidatus M. oxyfera-like bacteria in the examined sediments. This study showed the evidence of N-DAMO in coastal environments and indicated the importance of N-DAMO as a potential methane sink in coastal environments.

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