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1.
利用平行因子分析(PARAFAC)技术对藻华暴发季节太湖梅梁湾和开敞区水样中有色可溶性有机物(CDOM)的三维荧光光谱进行分析,获得代表类酪氨酸、类色氨酸和类腐殖酸等3种荧光组分,这3个组分的荧光得分值均与叶绿素a浓度呈极显著正相关,其中类腐殖酸物质荧光得分值占总分值的比例也与叶绿素a浓度极显著正相关,由此可以推测,蓝藻水华可能是太湖CDOM的一个重要来源,并极大地影响了湖泊CDOM的组成结构.为进一步探索蓝藻水华对湖泊CDOM的影响,于太湖梅梁湾湖岸进行藻华暴发和衰亡模拟试验.PARAFAC结果显示,模拟试验水样CDOM的三维荧光图谱同样含有3个组分,其中类酪氨酸和类色氨酸荧光峰位置与湖泊水样基本相同,而类腐殖酸物质荧光峰则有一定程度的蓝移,表明培养试验中有新的内源类腐殖酸物质产生.利用PARAFAC模型中的得分值计算后发现,初始叶绿素a浓度越高,类腐殖酸物质所占比例越大,而实验结束时添加了高浓度和中等浓度藻的2个处理中类腐殖酸物质对荧光的贡献率也有显著提高.因此,藻华的长期暴发可以显著改变湖泊CDOM的组成,导致类腐殖酸物质比例提高.  相似文献   

2.
After an explanation of the complex composition of the system of humic substances, some gravel deposits are described from whose open-pit boundaries there were taken water samples, their content of components of humic matter having been determined. Since spectroscopic analysis techniques yield spectra which are difficult to analyse and have a relatively low detection sensitivity, an indirect polarographic method was applied by which water-soluble humic substances can be determined very selectively down to a lower limit of 5 μg/1. Thus, enrichment in water or in adsorbing columns is not required. From the results found there are derived several statements concerning the occurrence of humic substances and fulvic acids in waters and conclusions about the possible influence on the hardening of concrete are given.  相似文献   

3.
Results of studying group and constituent composition of natural organic and mineral substances in silt bottom sediments of non-contaminated freshwater bodies are presented. The chemical composition of the investigated bottom sediments is shown to be complicated, diverse, and include products of autochthonous and allochthonous substance transformation. The necessity of further studying the concentrations of nutrients found in the bottom sediments of non-contaminated freshwater bodies, regarded as the “background” in estimating their environmental state, in studying processes occurring within water bodies, in determining natural and anthropogenic components of mineral and organic substances, as well as in estimating the balneologic value of the water bodies in question is substantiated.  相似文献   

4.
Savenko  A. V.  Savenko  V. S.  Pokrovskii  O. S. 《Water Resources》2021,48(2):285-290
Water Resources - A new method was used for experimental simulation of the sorption–desorption transformation of microelement composition of the adsorbed complex of solid substances of river...  相似文献   

5.
Outflow of chemical substances from the catchment area of the Karelian drainage network is discussed using hydrochemical data obtained in more than 80 rivers of Karelia over the period of many years. Weighted average characteristics of river water composition were found for ten large basins and for the entire region. Specific outflow was defined and its value was compared with atmospheric chemical precipitation; the difference made it possible to reveal the real input of chemicals from the catchment areas of Karelia.  相似文献   

6.
7.
Dissolved high molecular weight organic substances, like humic substances, can be characterized with regard to their molecular weight distribution using gel filtration chromatography (GFC). In addition, the adsorption properties, for example on activated carbon, can be described, if the substances are separated by hydrophobic interaction chromatography (HIC) in different fractions using a chromatographic column with a hydrophobic matrix. The retention time (Rt) of single chemical substances in this column can be used to characterize the hydrophobicity or hydrophility of each compound as well as of the high molecular weight organic matter. The hydrophobic interaction between the matrix of the column and the dissolved chemical compounds also depends on the hydrophobicity of the gel and the composition of the eluent. Relations between retention times, log P-coefficients (octanol/water partition) and K-values of isotherms on activated carbon (Freundlich equation) were found.  相似文献   

8.
The article presents the results of phytoplankton observations in lakes of the Kenti River system, which have been long subjected to the anthropogenic impact of processing wastewaters from the Kostomuksha Mining and Processing Works. Specific features of changes in the abundance and biomass of different systematic groups of phytoplankton as well as dimensional and species structure of phytoplankton communities are discussed. These changes are caused by the intensification of anthropogenic impact on lake ecosystems, in particular, by an increase in water mineralization and its content of biogenic substances, as well as by changes in the ion composition of water.  相似文献   

9.
The seasonal and year-to-year dynamics of the concentrations of biogenic elements and organic matter, as well as quantitative composition of phytoplankton in water of Selenga delta branches is studied. The distribution of those components from the mouth of the Kharauz branch (the main branch) to the water area of the Selenga shallows in different hydrological seasons is shown. The concentrations of nitrate nitrogen and phosphate phosphorus in the zone of mixing of river and lake waters have been found to drop by 30 and 50%, respectively, because of the consumption of those substances by phytoplankton.  相似文献   

10.
Morpho-physiological and biochemical parameters were determined in Scorpion fish Scorpaena porcus L. from two bays in the area of Sevastopol, which experience a high anthropogenic load. The effect of natural and anthropogenic factors on the size, weight, and age composition, as well as on the sex ratio of the fish from both populations, was studied. The relationships between the concentrations of chlororganic substances in the water of the bays, their accumulation in the liver and gonads of the fish, the activity of antioxidant enzymes in the blood, and the fractional composition of serum proteins were determined. A possibility for the use of the Scorpion fish as a indicator species for the biomonitoring and assessment of the environmental conditions in the coastal waters of the Black Sea was considered.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 238–246.Original Russian Text Copyright © 2005 by Rudneva, Shevchenko, Zalevskaya, Zherko.  相似文献   

11.
The chemical composition of atmospheric precipitation over the entire territory of Karelia is characterized on the basis of snow samples taken during the periods of maximum snow storage in 1996–2000. The concentration of chemical elements and their fallouts are considered within the northern, central, southern, and eastern regions of Karelia. The aero-technogenic effect of industrial centers of Karelia and the Archangelsk Province on the chemical composition of atmospheric precipitation is analyzed. The above material is generalized in the form of average statistical characteristics of the chemical fallouts of mineral, organic, and biogenic substances, heavy metals, and strong acids.  相似文献   

12.
A study was done to determine the concentrations of surfactants on the sea-surface microlayer and in atmospheric aerosols in several coastal areas around the Malaysian peninsula. The concentrations of surfactants from the sea-surface microlayer (collected using rotation drum) and from aerosols (collected using HVS) were analyzed as methylene blue active substances and disulphine blue active substances through the colorimetric method using a UV-vis spectrophotometer. The results of this study showed that the average concentrations of surfactants in the sea-surface microlayer ranged between undetected and 0.36 ± 0.34 μmol L−1 for MBAS and between 0.11 ± 0.02 and 0.21 ± 0.13 μmol L−1 for DBAS. The contribution of surfactants from the sea-surface microlayer to the composition of surfactants in atmospheric aerosols appears to be very minimal and more dominant in fine mode aerosols.  相似文献   

13.
The long term systematic investigations of ion composition components (bicarbonates, chlorides, sulphates, magnesium, calcium, sodium, potassium) and trophic status components (suspension, chlorophyll-a, mineral and organic forms phosphorus and nitrogen, carbon, silica) of water from the lake proper, its tributaries and atmospheric precipitation, which make up the main share of substance supply in to the lake, as well as the Angara river, being the source of substance discharge allowed the lake recent state to be evaluated in terms of both chemical pollution and possible eutrophication of its water. The similar (in terms of river runojf) periods of 50-ies and 80-ies have been compared. It was revealed that as a result of industrial activity 409 thousand tons of mineral substances (27.2 thousand tons of chlorides, 162 thousand tons of sulphates and over 200 thousand tons of organic substances) are supplied in the lake annually. The supply of substances of the anthropogenic origin is higher for the South Baikal than that for the North and Middle Baikal (the sum of mineral substances in 3.6 times; sulphates in 5 times, organic substances, including hydrocarbons in 7 times).The absence of abundant phytoplankton in the period studied when the ratio of silica to phosphorus is optimum (over 100), as well as a revers correlation between winter nitrogen content and spring of chlorophyll-a concentration in the Baikal water and revers dependence between the suspension and chlorophyll-a along the Selenga river valley lead to the conclusion that Baikal water contains toxicants. It is verified by the presence of polychlorbiphenyls (PCB), poly-chlordibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) for the whole food web with the maximum PCDD/PCDF (TEQ to 175 P g · g-1) concentration in the seal blubber. The levels are comparable with those reported for ringed seal (phoca hispida), living in the Baltic sea and Bar-row Strait Inlet in the Canadian Arctic.  相似文献   

14.
A natural decay of plant and animal biomass in aquatic environments results in the release of different simple structured organic substances into water. In our laboratory experiments we investigated whether some of them, e.g., starch or peptone, and also a complex yeast biomass can be transformed into humic-like substances by natural assemblages and some pure cultures of aquatic microorganisms. After a 6 months incubation most of the cultural media enriched with those natural organic substrates turned dark in color and humic-like substances (HS) could be isolated. However, the original substrate organic carbon was mainly mineralized in microbial cultures, and only about 3 % C was converted into HS. Total yields of HS differed in dependence of the individual substrate used (peptone > yeast > starch), the origin of inoculum (river > lake > groundwater), and the incubation temperature (20°C > 10°C). According to their elemental composition, and their spectroscopical and electrophoretic characteristics the microbially formed HS resembled natural aquatic humic matter, but were higher in aliphatic constituents (carbohydrates, peptides) and lower in aromatic structures. HS-like substances were also obtained from pure cultures of a bacterium Bacillus sphaericus and a fungus Cladosporium cladosporioides. The 13C and 15N isotopic contents of the microbially produced HS differed in dependence on the microbial inoculum and the type of organic substrates used, but in general they indicated anabolic processes to be mainly responsible for the humification of the simple organic substrates used in our experiments.  相似文献   

15.
Airborne surface-active organic substances can form adsorbed films at air-water and air-solid interfaces in the atmosphere. On the basis of considerable laboratory research, it has been suggested that these films can modify the microphysical processes of clouds and fog. The possible alterations of physical processes include retardation of the rate of growth and evaporation of water drops, passivation of cloud condensation nuclei, modification of drop coalescence efficiency, and the promotion of drop instability. The chemical structure of the film-forming compounds and the physical properties of the adsorbed films determine the degree to which the physical processes are modified. Upon consideration of the actual organic composition of the atmosphere, it was concluded that natural surface films will not greatly influence drop growth and evaporation. In addition, there is no definitive evidence from field experiments that other processes are influenced by natural organic films. The potential for useful weather modification through the intentional introduction of film-forming organic substances into the atmosphere was critically evaluated. Although numerous approaches have been suggested by laboratory studies, only the stabilization of airborne drops against evaporation has been unequivocally demonstrated in field experiments.  相似文献   

16.
乌梁素海沉积物腐殖质的组成及分布特征   总被引:2,自引:2,他引:2  
以乌梁素海为研究对象,应用化学方法对乌梁素海湖泊表层沉积物有机质含量、腐殖质组成、影响腐殖质的环境因子及腐殖化程度进行了研究,结果表明:乌梁素海表层沉积物有机质含量变化范围为1.06%~5.38%.有机质分布特征与表层沉积物所处的水力条件、水生植物分布、人为活动有关;腐殖质组成中,胡敏酸含量为0.65~2.78 g/kg,富里酸含量为2.19~8.72 g/kg,胡敏素是主体,含量在3.28~20.92 g/kg之间;腐殖质与环境因子的相关性分析中,各组分含量与有机质含量呈极显著相关.pH值与胡敏素含量呈显著负相关.溶解氧与富里酸、胡敏素含量分别呈极显著正相关、显著正相关.腐殖化程度分析中,随着有机质含量的上升,可提取腐殖质的相对含量下降.PQ值介于9.50%~27.06%之间,平均值为21.47%,变异较大,且腐殖化程度较低.  相似文献   

17.
Diatomic complexes from Upper Holocene sediments in Lake Glubokoe (Moscow Province) are analyzed. A unified reconstruction method is first applied to three most important hydrologic characteristics: temperature, cation-anion balance, and the concentration of biogenic substances. The species composition of diatomic complexes is studied with account for the bioindication significance of each species in terms of the above-listed parameters of the aquatic environment. A graphic method elaborated by L. V. Razumovskii is used to compare the structure of different diatomic complexes. A cyclic recurrence is revealed in the lake temperature regime over the last centuries of the lake existence. It is found that in the epoch of neosedimentogenesis, variations in all parameters under study are correlated.  相似文献   

18.
Exploring the chemical characterization of dissolved organic matter (DOM) is important for understanding the fate of laterally transported organic matter in watersheds. We hypothesized that differences in water-extractable organic matter (WEOM) in soils of varying land uses and rainfall events may significantly affect the quality and the quantity of stream DOM. To test our hypotheses, characteristics of rainfall-runoff DOM and WEOM of source materials (topsoil from different land uses and gullies, as well as typical vegetation) were investigated at two adjacent catchments in the Loess Plateau of China, using ultraviolet–visible absorbance and excitation emission matrix fluorescence with parallel factor analysis (PARAFAC). Results indicated that land-use types may significantly affect the chemical composition of soil WEOM, including its aromaticity, molecular weight, and degree of humification. The PARAFAC analysis demonstrated that the soils and stream water were dominated by terrestrial/allochthonous humic-like substances and microbial transformable humic-like fluorophores. Shifts in the fluorescence properties of stream DOM suggested a pronounced change in the relative proportion of allochthonous versus autochthonous material under different rainfall patterns and land uses. For example, high proportions of forestland could provide more allochthonous DOM input. This study highlights the relevance of soils and hydrological dynamics on the composition and fluxes of DOM issuing from watersheds. The composition of DOM in soils was influenced by land-use type. Precipitation patterns influenced the proportion of terrestrial versus microbial origins of DOM in surface runoff. Contributions of allochthonous, terrestrially derived DOM inputs were highest from forested landscapes.  相似文献   

19.
High-performance thin-layer chromatography with automated multiple development (AMD-HPTLC) was applied for the examination of pulp mill bleachery effluents from an alkali-oxygen-peroxide (EOP) bleaching stage of a sulfite pulp. A gradient based on methanol and dichloro-methane was developed for the separation of the effluent compounds over a wide range of migration distances. A series of reference substances such as lignin phenols and other aromatic acids, aldehydes, and alcohols as well as two resin acids were investigated in parallel using the AMD-HPTLC method. Characterization of the effluent compounds was possible using the migration distances and the recorded spectra. The composition of different samples of effluent were found to be very similar. The application of the AMD-HPTLC to effluent fractions from acidic liquid-liquid extraction using diethyl ether and from RP C18 solid-phase extraction allowed us to follow the behaviour of the effluent compounds in the extraction procedure.  相似文献   

20.
The distribution of oil hydrocarbons in bottom sediments of Onega Lake was examined. Their qualitative and quantitative composition was examined by methods of IR-spectroscopy and chromatography-mass spectrometry. The background concentrations of oil hydrocarbons in bottom sediments are evaluated and the polluted area is determined. The major regularities in oil hydrocarbon transformations under natural conditions and anthropogenic impact are identified. The quantitative development of the bacterial groups that take part in the transformation of complex organic substances and oil product derivatives in the case of emergency pollution of Petrozavodsk Bay water area by oil products is demonstrated.  相似文献   

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