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1.
Abstract

Mathematical transformation models of TDS (total dissolved salts) and organic substance concentration as BOD5 (biochemical oxygen demand) in water of the Angara River and the proposed Boguchan Reservoir have been developed. Having filled the reservoir to a water level of 208 m, in an average year it is shown that increase in surface water mineralization is expected in the cross-section of Boguchan Hydroelectric Power Station giving TDS of up to 20–40 mg/dm3, and values of BOD5 will increase to 2.0–3.9 mgO2/dm3. In a low-water year the value of BOD5 may be as great as 5 mgO2/dm3; mineralization, in contrast, decreases. Several years after reservoir filling, the values of BOD5 would decrease, but water quality of the upper part of the reservoir would still depend on the degree of treatment of wastewater discharged to it.

Editor D. Koutsoyiannis

Citation Savichev, O.G. and Matveenko, I.A., 2013. Evaluation of chemical composition changes of surface water in Boguchan Reservoir (Siberia, Russia). Hydrological Sciences Journal, 58 (3), 706–715.  相似文献   

2.
山东南四湖上级湖水质变化评价(2008-2014年)及成因分析   总被引：4，自引：3，他引：1  
基于南四湖上级湖6个监测点2008-2014年42个奇数月份的水质资料,选取溶解氧、化学需氧量(COD)、高锰酸盐指数(CODMn)、五日生化需氧量(BOD5)、氨氮、总磷和氟化物作为水质评价的指标.对水质指标的归一化方法进行了改进,采用主成分分析法对6个监测点的水质综合状况进行评价,根据得出的各月综合得分序列分析水质变化趋势.与2000-2007年南四湖上级湖的水质综合状况进行比较,2008-2014年水质明显变好.评价结果表明,同一监测点的水质在不同时间点上有明显变化,同一时间序列不同监测点的水质状况也有不同变化.此外,分析得出南四湖上级湖的主要水质影响指标为COD、CODMn和BOD5.结合评价结果,分析水质变化原因,入湖河流水质状况和湖区底泥是其重要影响因素.  相似文献   

3.
化学需氧量(COD)、五日生化需氧量(BOD_5)及溶解性有机碳(DOC)是指示湖泊水质的重要指标,然而上述指标测定通常耗费大量时间、试剂及人力物力且排放大量有害废液.有色可溶性有机物(CDOM)是溶解性有机物(DOM)中可以强烈吸收光谱中的紫外光和可见光的部分,数据测定耗时短、方便快捷,且样品处理过程环境友好,能在很大程度上反映湖泊水质.本研究基于2016年2、5和8月在太湖均匀布设的32个采样点进行样品采集,运用光谱吸收与三维荧光-平行因子分析(EEMs-PARAFAC)探究太湖CDOM的光谱吸收和荧光组分,探讨CDOM光谱指标对湖泊BOD_5、COD及DOC浓度等湖泊环境质量指标的可替代性.结果表明:(1)运用EEMs-PARAFAC方法解析出3种荧光组分:类腐殖酸C1、类酪氨酸C2和类色氨酸C3.(2) COD和BOD_5和DOC在空间上呈现出相似的分布趋势,不同水期的最高值均出现在竺山湾和梅梁湾,由西北湖区至中部敞水区、东南湖湾递减.(3)在不同水期,COD、BOD_5、DOC浓度和C1组分均表现为丰水期极显著大于枯水期和平水期,a_(254)在丰、平、枯水期间无显著性差异,最大值出现在丰水期;C2与C3组分均在枯水期和平水期极显著大于丰水期.(4)在不同水文时期,COD、BOD_5和DOC浓度均与a_(254)、类腐殖酸C1呈显著正相关,丰水期太湖COD、BOD_5和DOC浓度与CDOM光谱指标的线性相关性要优于枯水期和平水期.(5) CDOM光谱指标在不同水文时期均能很好地替代COD、BOD_5和DOC等作为反映太湖水体中有机物污染程度及湖泊水质的指标.  相似文献   

4.
The wastewater treatment is carried out in two parallel pond groups: South–9200 m3/d, 1748 kg/d BOD5, preliminary clarifier (1.1 ha, 22000 m3), three ponds (9.8 ha, 88000 m3), naturel aeration; North ?5700 m3/d, 2394 kg/d BOD5, Imhoff tank, three ponds (7.9 ha, 71000 m3), the pond 1 artificially aerated by gyroscopic units. The different loads of 15.9 and 33.7 g/m3 d BOD5 results in rates of removal of 11.2 and 22.5 g/m3d BOD5, resp. Therefore, the efficiency of the naturally aerated system is higher than that of the artificially aerated system. In the aerated system mainly the bacterial growth is promoted, a typical algal state being achieved only slowly, whereas the naturally aerated system gains a summer-time algal maximum in the ponds 2 and 3, which is accompanied already by zooplankton populations. In the dynamics of the biomass development, the higher efficiency of the four-stage, naturally aerated system is especially obvious.  相似文献   

5.
The presented results have been obtained in a study of the concentrations and composition of aliphatic and polycyclic hydrocarbons in bottom sediments of Volga delta branches and in its shallow zone (2009–2010), as well as the Caspian Sea proper (2010–2013). Oil hydrocarbon pollution has been found to manifest itself mostly in Volga delta branches, which, despite the low concentrations (up to 54.5 μg/g), showed higher hydrocarbons share in Corg (up to 33.8%), while the composition of alkanes suggested their oil genesis. The geochemical barrier the Volga–the Caspian Sea prevents anthropogenic hydrocarbons from entering the open parts of the Caspian. Bottom sediments in the shallow zone of the Northern Caspian, represented by coarse-grained material, are now polluted by oil hydrocarbons to a lesser extent compared with other areas. The highest concentrations of aliphatic hydrocarbons (up to 178 μg/g) were recorded in the deepsea bottom sediments of Derbent Depression and in depressions of the Middle and Southern Caspian. These areas show a higher concentration of Corg (up to 9.884%) and a low concentration of hydrocarbons in Corg (up to 0.16%), while odd high-molecular homologues (n-C25–C31) dominate in the composition of alkanes.  相似文献   

6.
Thirteen alicyclic compounds (C5… C7) are examined for their biochemical degradability in a laboratory activating tank and in two respirometers (Warburg, Sapromat). The tests were performed with adapted and nonadapted activated sludge. In addition, the COD was determined by three different methods. With the exception of cycloheptane (BOD < 25% of the BODtheor.), six compounds prove to be easily degradable (BOD > 45% of the BODtheor.) and six compounds prove to be degradable (BOD 45… 25% of the BODtheor.).  相似文献   

7.
The composition of hydrocarbons (aliphatic and polycyclic aromatic) is studied in the surface layer of bottom sediments of the Ivankovo Reservoir. Their concentrations are found to be high both per dry mass and in the composition of Corg. The concentration range was 0.42 to 28.15% for Corg, 141.9 to 3451.8 μg/g for aliphatic hydrocarbons (0.2–51.2% Corg), and 28.2–9161 ng/g for polycyclic aromatic hydrocarbons ((0.04–6.58) × 10?3 % Corg). The distribution of hydrocarbons is shown to be determined not only by the lithologic type of sediments, but also by their input from petroleum and pyrogenic sources.  相似文献   

8.
The system consists of three preliminary clarifiers and two ponds operating in series. It drains 100,000 to 120,000 m3 highly loaded wastewater per year over the ground. In dependence on load, in the pond 1 a midsummer-time bacterial maximum of up to 800 m3/l occurs. The algal biomass, too, shows an annual curve with one peak; the maximum is independent of the ice cover and varies with the seasons. The BOD5 shows a spring maximum and a summer maximum independent of the biomasses and their variations. In the second pond only slight changes are found from June till October; here prevail algae and a maximum of flagellates. Although a stage of filtrators and consumers is lacking, the system can be regarded as a sewage pond system with a reduction of BOD5 by 73%.  相似文献   

9.
梯级筑坝对黑河水质时空分布特征的影响   总被引：1，自引：0，他引：1  
为探究梯级大坝建设对河流水质变化规律的影响,将黑河上中游划分为坝上河段、坝下河段及自然河段,于2017年12月-2018年8月选取了24个主要控制断面进行水质调查,并采用多元统计的方法对比分析了不同时空尺度上的水质分布特征.结果表明:黑河上中游水质时空变化的主要影响因子为水温(WT)、pH值、溶解氧(DO)、电导率(EC)、总氮(TN)、总磷(TP)和五日生化需氧量(BOD_5).空间尺度上,WT、EC、BOD_5、高锰酸盐指数(CODMn)、TN等指标具有显著性差异,其中坝上河段受BOD_5、CODMn影响较大,自然河段WT、EC和TN为关键指标,而各个因子对坝下河段水质影响较小.时间尺度上,WT、EC、BOD_5、氨氮与季节变化存在明显相关性,是不同河段水质时间变化的控制因子,且大多数水质因子在非汛期变化最明显.降水、温度、水文条件等季节性影响因素和梯级水库联合运用模式是该区域水质时间差异的主要原因;空间差异主要受祁连、张掖地区外源性污染物排放以及筑坝环境下水动力条件改变而产生的沉积滞留效应和沿程累积效应影响.研究表明,外源性污染源依然是导致水质变差的主要因素,梯级筑坝则是导致水质变差的间接因素.因此控制该区域人类活动所造成的外源性污染源,并针对不同种类污染物的季节变化特征实施合理的水库运行方式是改善水电梯级开发河段水质状况的关键.  相似文献   

10.
The effluent from biological treatment plants of cane sugar factories undergoes a final purification in laboratory models with a Chlorella culture at volume loads of 76… 325 mg/l. d BOD5 or 121… 555 mg/l-d COD. The coefficient of removal on the basis of BOD5 is found to be linearly negatively correlated with the retention time, but independent of the substrate concentration and composition as well as of the pre-treatment of the wastewaters (aerobic or anaerobic). A dimensioning on the basis of the COD is not possible because of the high phytoplankton content in the effluent of the ponds.  相似文献   

11.
The difficulties arisen in an assimilation pond, as it is called, after 17 years of operation were solved by a stabilization system for the purification of effluents and utilization for fish breeding. It consists of two basins (0.56 and 1.04 ha) and a fish pond (15.58 ha) to which water can flow from a brook by-passing the system. When the stabilization system had worked for 6 years, it was proved that in the case of the average daily intake of milk of 93,846…118,134 litres, effluents flowing out of the dairy plant amounted to 205.28…228.53 m3, on average. The BOD5 of effluents ranged from 201.33 to 261.73 kg/d and the total solids ranged from 95.5 to 139.3 kg/d on average. The average daily outflow from the pond amounted to 394.7…1567.0 m3 of water with 4.1…23.8 kg of BOD5 and with 29.3…112.4 kg of total solids. The average decrease of the main nutrients and extractable substances ranged from 62.8% (Ca2+) to 100% (NO?3). Only the BOD5 value at the end of the growing season in 1984 (8.4…10.3 mg/l) exceeded three times the standards for the admissible pollution of the receiving stream.  相似文献   

12.
The study aimed to determine the spatial distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Segara Anakan nature reserve and their potential origins using gas chromatography–mass spectrometry. Total alkane concentrations ranged from 3755 to 129,027 μg kg−1, and the concentrations of 16 PAHs ranged from 375 to 29,517 μg kg−1. The ratios of specific n-alkanes (e.g., CPI24–34, WaxCn, and Paq), including a new proposed index, terrestrial–marine discriminant (TMD), as well as the ratios of selected PAHs (e.g., Ant/∑178, Fl/∑202, BaAnt/∑228, and IPyr/∑276), showed that the sources of hydrocarbons in the sediments were generally biogenic, including both terrigenous and marine, with an anthropogenic pyrolytic contribution (petrogenic and biogenic combustion). For the environmental risk assessment, a sediment quality guideline (SQGs) comparison indicated that the station risk levels ranged from low to medium-low, except for R6, which has a greater impact on the ecological risk for marine organisms.  相似文献   

13.
Hydrocarbon samples taken from bottom sediments of the Barents Sea in summer 2010 in two grounds near the Shtokman Gas Condensate Field were studied. The concentration of hydrocarbons was found to increase with sampling depth along with a decrease in Corg concentration. The composition of alkanes had mixed genesis: autochthonous homologues (n-C16-C17) dominated in the low-molecular domain, while oil ones dominated in the high-molecular domain; light polyarenes dominated in the composition of polycyclic aromatic hydrocarbons. The seepage of hydrocarbons from the sedimentary stratum and their transformation in the surface layer of bottom sediments are considered as their major source. The relatively low hydrocarbon concentrations converted to dry mass and in the composition of Corg are supposed to be due to a decrease in the intensity of fluid flows, since the hydrocarbon reservoirs of the Shtokman Field are firmly capped by an impermeable stratum of mostly clay rocks.  相似文献   

14.
Reduction of the Concentration of Bacteria and Coliphages along the Flowing Stretch of a Treated Sewage Channel The efficiency of surface waters to eliminate E. coli, fecal streptococci, Salmonella spp., and coliphages was evaluated in a small river which receives treated wastewater and which is rich in submerged macrophytes. The study took place between April and December, 1994. Total colony count, BOD5, O2 concentration and water temperature were determined in the river as well. As the river does not receive additional water downwards along its 17.2 km course, dilution effects could be ruled out as the cause for the elimination of the microorganisms. The reduction is assumed to happen rather due to sedimentation, grazing, and adsorption to the submerged waterplants. Immediately after discharge of the wastewater, the river water contained about 105 cfu/100 mL E. coli and 104 cfu/100 mL fecal streptococci, about 1000 pfu/100 mL coliphages, and, as a rule, was positive for salmonella in 10 mL. The reduction of E. coli, fecal streptococci, salmonella, clostridia, and coliphages at the end of the course was 1 to 2 orders of magnitude. This reduction took place mainly within the first 4.7 km, a part in which, due to low flowing velocities, suspended solids settle down efficiently. Besides, at the end of this part the submerged waterplants are especially abundant. The reduction of suspended solids correlated positively with that of BOD5, bacteria, and coliphages. The reduction of microorganisms was not sufficient to fulfill the requirements of the European Community guidelines for bathing waters and for surface waters used as drinking water source. The regenerating capacity of surface waters is not sufficient to eliminate pathogens from convenionally treated wastewater. Therefore, tertiary treatment is necessary to keep receiving waters reasonably free from pathogens.  相似文献   

15.
The results of studying the composition of hydrocarbon gases (C1–C5) and organic matter in bottom sediments of the Ivankovo Reservoir in 1995, 2004, and 2005 are given. The methods used in the study include vapor-phase gas chromatography, instrumental pyrolysis gas chromatography, and mass-spectrometry for determining organic carbon δ 13Corg. The gas field of bottom sediments in different regions of the reservoir varies widely in terms of gas saturation and the spectrum of hydrocarbon gases. This suggests the heterogeneous composition of organic matter in the sediments and different conditions of its input and transformation processes. The gases were found to contain saturated hydrocarbons from methane to pentane C1–C5, including isomers i-C4 and i-C5 and unsaturated compounds C2–C4. A correlation was found to exist between methane distribution and the distribution of its more high-molecular homologues, which confirms their genetic relationship in bottom sediments. The obtained results show an increase in the rate of microbiological processes and organic matter transformation for most regions in the Ivankovo Reservoir. The only exceptions are the zones of Moshkovichskii Bay and the sections at Gorodnya and Konakovo, where technogenic organic matter is being accumulated. The high information value of hydrocarbon gases as biogeochemical markers of the sources of organic matter and the rates of its transformation is demonstrated. The isotopic composition of organic-matter carbon in the bottom sediments of the Ivankovo Reservoir δ 13C varies from ?26.21 to ?30.86‰.  相似文献   

16.
Basic principles determining and substantiating the contents of organics in secondary effluents were formulated and discussed. It has been shown that the activated sludge process, if optimally designed and operated, can produce secondary effluents with soluble carbonaceous BOD5 values below 5 mg/1 and suspended solids concentrations approaching 10 mg/1. While the total values of BOD5 are significantly influenced by SS concentrations, the total values of COD are influenced mostly by soluble refractory organics present in raw wastewaters and formed in the process as microbial waste products.  相似文献   

17.
It is proposed to evaluate two theoretical characteristics, i.e., BOD (biochemical oxygen demand) and k 0 (the coefficient of oxidation rate by new formulas based on two experimental variables: BOD T and BOD2T (biochemical oxygen consumption in two periods T and 2T day, respectively). The formulation and an analytical solution are given for a direct problem describing the process of biochemical oxidation of organic matter (OM) in a water volume in the absence of aeration (e.g., in a water body under ice or in a sealed flask used to measure biochemical oxygen consumption). The problem is solved based on the closed (modified) Streeter–Phelps system. Unlike the classical Streeter–Phelps system, the closed system excludes physically incorrect solutions (e.g., negative concentrations of dissolved oxygen (DO)) [4]. The solution of the direct problem is used to formulate an inverse problem, whose solution is given in the form of formulas for evaluating BOD and k 0. These formulas are used to compile tables to illustrate the essence of the proposed method.  相似文献   

18.
Lake Gucheng is located in the southeast of Nanjing, with an area of 24.3 km2, an average depth of 2 meters. The macrophytes of the lake were used to be abundant and their biomass was about 4.96 mg·m-2. The annual average contents of total phosphorus (TP), total nitrogen (TN), PO3- -P, CODMn and BOD5 0.03, 1.31, 0.005, 3.61 and 1.46 mg·L-1, respectively. Thus, the water quality of this lake is quite well. Recently, the water quality in pari of the lake became worse because of some unreasonable exploitation and utilization of bioresources. The interactions between phytoplankton (N1), macrophyte (N2), fish (N3), crab (N4) were studied here. The macrophyte has great influences on both phytoplanktons, fish and crab, controlling the water quality and maintaining the fishery productivity. On the other hand, the phytoplankton, fish and crab also influence the macrophyte. It is key method of ecological management to maintain the macrophyte by fishery culture. Therefore, a modified Lotka-Volterra model has been established to estimate the interaction between N1, N2, N3, N4 and the influences of some water environmental parameters on these aquatic organism, environmental and economic effect. The main model consists four compart-mental models and four submodels, involved 12 external variables, 8 state variables, 19 universal constants and 11 parameters. The values of most parameters were found from our experiments and calibrated by the model and actually measured data. The model has been validated by comparison the computed and experimental data of phytoplankton and macrophyte. The theoretical outputs showed a good agreement with the measured data. This model predicated that if the standing crop offish and crab was higher than 2.65 ·m-2 during springtime in this lake, macrophytes would not grow, chlorophyll a content would arrive 34.8 mg·m-3 and the water quality would decrease. If the macrophyte grow well, the maximum fishery productivity would be about 1 600 t. In this case, the annually averaged phytoplankton chlorophyll a content should be 3.69 mg·m-3, which is lower than the criterion (10 mg·m-3) for eutrophic state. From 1991 to 1996, Lake Gucheng was managed with this model, its water quality maintain quite well, chlorophyll a content decreased from 3.51 (1991) to 1.89 mg·m-3 (1994). Meanwhile, the fishery productivity increased and the economic effect heightened year by year.  相似文献   

19.
At present the concentrations of polycyclic aromatic hydrocarbons in sediments from the Great Barrier Reef are remarkably low. The baseline levels range from <0.01 μg kg?1 dry wt. for benzo(k)fluoranthene and benzo(a)pyrene to <0.82 μg kg?1 for chrysene. Measurable levels of polycyclic aromatic hydrocarbons have only been found in small areas close to sites frequently visited by power boats. Sediments from Townsville and Gladstone Harbours on the coast adjacent to the reef are polluted with polycyclic aromatic hydrocarbons to a similar degree to that reported for coastal sediments in similar locations in other parts of the world.  相似文献   

20.
Estimation of internal nutrient release in large shallow Lake Taihu,China   总被引：1，自引：0，他引：1  
Based on field investigation of wave, sediment suspension and the changes in nutrient concentration of the water column in Lake Taihu, China, we proposed two release models to quantify nutrient release under static and dynamic conditions, respectively. Under static conditions, nutrient release from sediments to the overlying water mainly depends on chemical diffusion induced by concentration gradient, in which the nutrient release is controlled by the temperature, dissolved oxygen concentration in the sediment-water interface, oxidation-reduction potential and the concentration difference between porewater and overlying water. Under dynamic condition (or disturbed condition), both dissolved and particulate nutrients in sediments are released into the water column because of wind-induced sediment suspension. The amount of nutrient release under dynamic conditions is larger than that under the static condition. The release of dissolved nutrients, however, does not increase because the wind induced turbulence made oxidation of metallic elements such as Fe (ferric iron), Mn which are capable of precipitating soluble reactive phosphate (SRP). Under dynamic conditions, therefore, the release of total phosphorus (TP) increases dramatically but the release of SRP is close to those under static conditions. In sediments of Lake Taihu, high Fe content leads to a high ratio of Fe to P contents in sediments (Fe:P ratio). Under dynamic conditions, therefore, nutrient release is controlled by the intensity of disturbance, sediment consolidation and nutrient content in sediments. As for dissolved nutrients, especially SRP, the release is also controlled by the intensity of dynamic re-oxidation, Fe content in sediments and nutrient concentration gradient between porewater and overlying water. Based on these two release modes, the release flux in Lake Taihu has been estimated. In the static condition (i.e. laboratory experimental condition), total release of NH4 +-N for whole lake is ca. 10,000 ton/a, and PO4 3?-P is ca. 900 ton/a. In the dynamic condition, nutrient release following sediment suspension was estimated according to three different intensities of wind forcing which were defined as “calm” (wind speed is less than 2 m/s), “gentle” (wind speed is greater than 2 m/s and less than 6 m/s) and “gust” (wind speed is greater than 6 m/s). The release rate in the condition of “calm” was estimated in terms of the nutrient release in the laboratory experimental static condition; whereas the release rate in conditions of “gentle” and “gust” was estimated in terms of measurement during sediment resuspension conducted in flume experiments. With the observation of wind velocity and frequency in 2001, each type of wind forcing took the frequency of 12%, 82% and 6% for “calm”, “gentle” and “gust”, respectively. The yearly release of nitrogen was 81,000 ton and phosphorus was 21,000 ton, which is about 2–6 folds of annual external loading, respectively.  相似文献   

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