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1.
Huan Jing Ke Xue ; 38(11): 4501-4512, 2017 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965393

RESUMO

Water samples were collected from the Yellow and Bohai seas during November 2013 and the chromophoric dissolved organic matter (CDOM) and nutrients concentrations were investigated, including their composition, source and distribution characteristics. CDOM was analyzed by excitation-emission matrix spectroscopy (EEMS) in combination with a parallel factor analysis (PARAFAC). Three terrestrial humic-like substances (C1, C2, and C3) and one protein-like (C4) substances were identified. The three terrestrial humic-like components had a similar horizontal distribution, decreasing from inshore to offshore. The protein-like component, showed higher values for both inshore and offshore areas in the Yellow Sea at the surface layer and the middle layer of the Bohai Sea, while in other layers it had a similar distribution pattern as the terrestrial humic-like components. In the Bohai Sea, the dissolved inorganic nitrogen (DIN) concentration showed a decreasing trend from inshore to offshore areas and the concentration of dissolved inorganic phosphorus (DIP) gradually decreased from the Caofeidian coastal and central areas to other adjacent areas. The dissolved organic nitrogen (DON) showed an increasing from inshore to the central area of the Bohai Sea. DIN and DON were higher in surface layer than in the bottom layer and for DIP this was the opposite in the Bohai Sea. In the Yellow Sea, DON concentrations showed a decreasing trend from inshore to offshore areas. DIN and DIP had higher concentrations at inshore areas in the surface and middle layers, while in the bottom layer they had higher concentrations in offshore areas. The vertical distribution of the DIN and DIP showed higher values in the bottom layer than surface layers and for DON this was the opposite. These results also showed that the concentrations of DIN, DON, and DIP in the Bohai sea were overall higher than the Yellow Sea. A discriminant analysis was performed through redundancy analysis (RAD) of these water quality parameters, including the four fluorescent components, an absorption coefficient (a355), chlorophyll a concentration, conductivity, dissolved oxygen (DO), dissolved organic carbon (DOC), DIN, DON, and DIP. The RDA indicated that the four fluorescent components are mainly affected by terrestrial inputs. DOC was affected by both terrestrial and marine sources but terrestrial inputs were the major contributor. It was also indicated that the DIN concentration was affected by terrestrial inputs in the Bohai Sea area and by both terrestrial and marine sources in the Yellow Sea. DON concentrations were mainly affected by marine sources in the Bohai Sea and terrestrial inputs in the Yellow Sea. DIP concentrations were affected by both terrestrial and marine sources in the studied areas.

2.
Huan Jing Ke Xue ; 35(3): 924-32, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24881379

RESUMO

An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor (PARAFAC) analysis and CHEMTAX. The PARAFAC model was applied to fluorescence excitation-emission matrix (EEM) of 23 algae species and 12 fluorescent components were identified according to the residual sum of squares and specificity of the composition profiles of fluorescent. Based on the 12 fluorescent components, the algae species at different growth stages were correctly classified at the division level using Bayesian discriminant analysis (BDA). Then the reference fluorescent component ratio matrix was constructed for CHEMTAX, and the EEM-PARAFAC-CHEMTAX method was developed to differentiate taxonomic groups of algae. When the fluorometric method was used for 531 single-species samples, the average correct discrimination ratio (CDR) was 99.1% and the correct discrimination ratios (CDRs) were 100% at the division level except Chlorophyta, the CDR of which was 97.5%. The CDRs for 95 mixtures were above 98.5% for the dominant algae species and above 90.5% for the subdominant algae species, with average relative contents of 69.7% and 26.4%, respectively. This technique would be of great aid when low-cost and rapid analysis is needed for samples in a large batch.


Assuntos
Clorófitas/classificação , Monitoramento Ambiental , Lagos/análise , Teorema de Bayes , Análise Fatorial , Fluorescência , Espectrometria de Fluorescência
3.
Huan Jing Ke Xue ; 34(1): 51-60, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23487918

RESUMO

The distribution and estuarine behavior of fluorescent components of chromophoric dissolved organic matter in the seawater of outer Yangtze Estuary were determined by fluorescence excitation emission matrix spectra combined with parallel factor analysis. Six individual fluorescent components were identified by PARAFAC models, including three terrestrial humic-like components C1 [330 nm/390(430) nm], C2 (390 nm/480 nm), C3 (360 nm/440 nm), marine biological production component C5 (300 nm/400 nm) and protein-like components C4 (290 nm/350 nm) and C6 (275 nm/300 nm). The results indicated that C1, C2, and C3 showed a conservative mixing behavior in the whole estuarine region, especially in high-salinity region. And the fluorescence intensity proportion of C1 and C3 decreased with increase of salinity and fluorescence intensity proportion of C2 kept constant with increase of salinity in the whole estuarine region. While C4 showed conservative mixing behavior in low-salinity region and non-conservative mixing behavior in high-salinity region, and fluorescence intensity proportion of C4 increased with increase of salinity. However, C5 and C6 showed a non-conservative mixing behavior and fluorescence intensity proportion increased with increase of salinity in high-salinity region. Significantly spatial difference was recorded for CDOM absorption coefficient in the coastal region and in the open water areas with the highest value in coastal region and the lowest value in the open water areas. The scope of absorption coefficient and absorption slope was higher in coastal region than that in the open water areas. Significantly positive correlations were found between CDOM absorption coefficient and the fluorescence intensities of C1, C2, C3, and C4, but no significant correlation was found between C5 and C6, suggesting that the river inputs contributed to the coastal areas, while CDOM in the open water areas was affected by terrestrial inputs and phytoplankton degradation.


Assuntos
Monitoramento Ambiental/métodos , Compostos Orgânicos/análise , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , China , Estuários , Oceanos e Mares , Rios , Estações do Ano , Água do Mar/análise , Poluentes Químicos da Água/metabolismo
4.
Huan Jing Ke Xue ; 28(11): 2416-24, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-18290458

RESUMO

Based on the data from four cruises that carried out in the Changjiang River estuary and its adjacent areas from 2002-04 to 2003-02, the seasonal variation and spatial distribution of nutrients were analyzed, and the relationship between nutrients condition and the harmful algal blooms (HABs) was also discussed. Results showed that the annual average concentration of nutrient was (17.93 +/- 2.46) micromol x L(-1) for DIN, (0.59 +/- 0.11) micromol x L(-1) for PO4(3-) -P, (15.34 +/- 3.23) micromol x L(-1) for SiO3(2-) -Si, and the study area was in the state of eutrophication. The average concentration of nutrient showed a remarkable seasonal fluctuation with the higher value in autumn and winter and lower value in spring and summer. The spatial distribution of the nutrients was typically such that the concentrations of DIN, PO4(3-) -P and SiO3(2-) -Si decreased from inshore to offshore area, and the contours generally decreased rapidly in down-coast directions. DIN and SiO3(2-) -Si of the study area were largely contributed by Changjiang River diluted water and other terrigenous inputs, while PO4(3-) -P mainly by Changjiang River diluted water and the Taiwan Warm Current. The following HABs showed that its occurrences were usually laid in the areas with higher nutrients and lower total suspended particles (TSP).


Assuntos
Eucariotos/crescimento & desenvolvimento , Nitrogênio/análise , Fosfatos/análise , Estações do Ano , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Eutrofização , Oceanos e Mares , Rios , Compostos de Silício/análise , Movimentos da Água
5.
Huan Jing Ke Xue ; 27(5): 862-8, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16850823

RESUMO

The growth-inhibiting effects of Gemini1231 surfactant on Prorocentrum donghaiense, Alexandrium tamarense, Gymnodinium sp., Heterosigma akashiwo, Skeletonema costatum , Platymonas helgolanidica and Platymonas subcordiforus were investigated. The results demonstrate that the growth of P. donghaiense, A. tamarense and H. akashiwo was strongly inhibited in medium containing Gemini1231 from 0.2 to 0.5 mg x L(-1), and the S. costatum was also inhibited at concentrations above 0.5 mg x L(-1). However, the effects of this surfactant on the growth of Gymnodinium sp. and two beneficial green microalgae tested were negligible under the same treatment, indicating the potential for the selective control of red tide organisms. In addition, the analysis of the correlation between the inhibitory effect of the Gemini1231 on the algae tested and fatty acid composition of the algae implied that the differences in the fatty acid composition, especially the proportion of PUFAs, were responsible for the species-specific responses to biquaternary ammonium salt.


Assuntos
Calcitriol/análogos & derivados , Eucariotos/efeitos dos fármacos , Eutrofização/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Calcitriol/farmacologia , Eucariotos/crescimento & desenvolvimento
6.
Huan Jing Ke Xue ; 25(1): 14-9, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15330413

RESUMO

A "cW (pollutant concentration in water) Balance Method" was proposed, and the kinetic parameters for bioconcentration of No. 0 diesel water-accommodated fraction by phytoplankton was measured and calculated by a modified bioconcentration model with non-linear fitting software. The data and parameters obtained by "cW Balance Method" showed well correlationship with those by the extraction of ultrasonication bath with the equilibrium method. The technique proposed in the present study is particularly well suited for the study on the bioconcentration of organic pollution toxins in the field for its convenience, simplicity, veracity and reliability.


Assuntos
Gasolina , Fitoplâncton/metabolismo , Poluentes Químicos da Água/análise , Cinética , Modelos Teóricos , Oceanos e Mares
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