On-site studies of an experimental air curtain on the dam of the Krivoporozhsk hydroelectric station

A large group of co-workers of the All-Union Scientific-Research Institute of Hydraulic Engineering (VNIIG), Leningrad branch of the All-Union Planning, Surveying, and Scientific-Research Institute (Lengidroproekt), A. N. Krylov Central Scientific-Research Institute (TsNII), Marine Physical Instruments Central Scientific-Research Institute (Morfizpribor), and other organizations participated in the on-site studies. The main participants were V. A. Vizirov, S. E. Volodin, L. S. Voronova, R. M. Drabkin, A. E. Svyatoslavskii, R. A. Tamm, G. S. IShifrin, R. I. Eikhfel'd, and B. A. Emmus.     

Water transport and power network (WTPN) of the Russian Federation

A brief account of the concept developed in 1993 on orders of the Ministry of Fuel and Power of the Russian Federation by a group of authors: A. E. Asarin, T. P. Dotsenko, V. D. Novozhenin, G. L. Sarukhanov (State Planning, Surveying, and Research Institute), V. F. Samarin, R. P. Stepanov, V. I. Fedoryak, M. A. Shestopal (State River Transport Planning Institute), and A. A. Belyakov (Moscow State Construction University).     

Wave reworking of reservoir banks composed of flysch in Slovakia

Conclusion A wave regime on reservoirs leads to erosion of their banks, to wave scour. The total length of the shoreline of reservoirs in Slovakia is more than 300 km, of which about 50% is accounted for by those which are characterized by a large storage capacity and intense wave action (Orava, Bolsaja Domasa, Liptovská Mara, Vihorlat). Wave scour in combination with landslides develops rapidly where the banks are composed of thick accumulations of loose deposits. On the basis of the data of long-term investigations on the Orava and Bolsaja Domasa reservoirs it was established that a prediction of the development of reworking of the banks of reservoirs with time under the engineering-geologic conditions of the Carpathian flysh by the methods of Soviet authors E. G. Kachugin and B. A. Pyshkin is found to be reliable. The works of other authors (B. A. Pyshkin, S. V. Rusakov, V. L. Maksimchuk, Yu. N. Sokol'nikov, V. S. Shaitan, et al.) served as the basis for planning protective measures to limit the development of wave abrasion on the indicated reservoirs. These measures were developed in 1974–1975 at the department of geotechnics of SVST in Bratislava [14]. Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 46–50, May, 1979.     

Concerning the maximum allowable values of indices of the state of structures at the Zagorsk pumped-storage station

Conclusions On the basis of the results of observations on structures of the Zagorsk PSS during temporary operation (since 1988), NIIéS and Gidroproekt developed a system of criterion indices of the state of the structures. The maximum allowable values of these indices determined on the basis of analyzing the results of calculations and experimental and on-site observations permits routine monitoring of the state of structures and ensures their safe operation. In addition to the authors, A. I. Yudkevich, A. A. Lobach, Yu. E. Mirzak, L. E. Kanygin, and L. P. Gal'perina participated in the studies to determine the maximum allowable values of the condition of the structures at the pumped-storage station. Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 11–18, April, 1996.     

Nematode suppression and growth stimulation in corn plants (Zea mays L.) irrigated with domestic effluent

Treated wastewater has great potential for agricultural use due to its concentrations of nutrients and organic matter, which are capable of improving soil characteristics. Additionally, effluents can induce suppression of plant diseases caused by soil pathogens. This study evaluates the effect of irrigation with effluent in a UASB reactor on maize (Zea mays L.) development and on suppression of the diseases caused by nematodes of the genus Meloidogyne. Twelve lysimeters of 1 m(3) each were arranged in a completely randomized design, with four treatments and three replicates. The following treatments were used: T1 (W+I), irrigation with water and infestation with nematodes; T2 (W+I+NPK), irrigation with water, infestation with nematodes and fertilization with nitrogen (N), phosphorus (P) and potassium (K); T3 (E+I), irrigation with effluent and infestation with nematodes; and T4 (E+I+P), irrigation with effluent, infestation with nematodes and fertilization with phosphorus. The plants irrigated with the effluent plus the phosphorus fertilizer had better growth and productivity and were more resistant to the disease symptoms caused by the nematodes. The suppression levels may have been due to the higher levels of Zn and NO(3)(-) found in the leaf tissue of the plants irrigated with the effluent and phosphorus fertilizer.     

Effect of organic load and nutrient ratio on the operation stability of the moving bed bioreactor for kraft mill wastewater treatment and the incidence of polyhydroxyalkanoate biosynthesis

This paper studies the effect of organic load rate (OLR) and nutrient ratio on operation stability of the moving bed bioreactor (MBBR) for kraft mill wastewater treatment, analyzing the incidence of polyhydroxyalkanoate (PHA) production. The MBBR operating strategy was to increase OLR from 0.25 ± 0.05 to 2.41 ± 0.19 kg COD m(-3) d(-1) between phases I and IV. The BOD(5):N:P ratio (100:5:1 and 100:1:0.2) was evaluated as an operation strategy for phases IV to V. A stable MBBR operation was found when the OLR was increased during 225 days in five phases. The maximum absolute fluorescence against the proportion of cells accumulating PHA was obtained for an OLR of 2.41 ± 0.19 kg COD m(-3)d(-1) and a BOD(5):N:P relationship of 100:1:0.2. The increase of PHA biosynthesis is due to the increased OLR and is not attributable to the increased cell concentration, which is maintained constant in stationary status during bioreactor biosynthesis.     

节灌控排条件下氮磷迁移转化规律研究

针对我国灌排面积不断增加、水资源利用效率不高、化肥流失严重等问题,结合田间对比试验,考虑节水灌溉与控制排水的协同效应,通过控制变量法研究灌排因素对排水量、氮磷流失量的影响和土壤水中氮磷迁移转化规律,发现：浅灌深蓄（G1）模式下控制排水（L1）的排水量较非控制排水（L2）的排水量减少了7.59%,浅勤灌溉（G2）模式下L1的排水量较L2处理下减少了8.44%;同时L1处理下NO3--N、NH4＋-N、TN、TP流失量分别比L2处理下的流失量减少了34.08%、7.11%、11.31%、56.4%。由此可知,控制排水对减少排水量和氮磷流失量具有明显的效果,G1L1的灌排组合更有利于控制田间排水量、减少氮磷流失。     

合肥市区周边地表水体形态磷的研究

选取合肥市周边代表性的地表水体董铺水库、天鹅湖、翡翠湖为研究对象,运用地表水和污水监测技术规范中的标准方法,对3个水体的TP、DTP、PP、DIP、DOP进行监测,并做了初步研究和分析。结果表明,天鹅湖水体中总磷的平均浓度为O,102mg／L,符合V类标准要求,水体中磷主要以DTP和DOP的形式存在,TP—DIP显著正相关;董铺水库总磷的平均浓度为0．031mg／L,达到Ⅲ类标准,磷主要以DTP和DIP的形式存在,其中TP与DTP之间高度显著正相关;翡翠湖水体中总磷的平均浓度为0．060meCL,达到IV类标准,水体中磷主要以ADTP的形式存在,其@TP与PP之间显著正相关,PP在该湖泊中占有重要的地位。     

Effects of Food Type,Habitat, and Fish Predation on the Relative Abundance of Two Amphipod Species,Gammarus fasciatus and Echinogammarus ischnus

We evaluated the abundance patterns of Gammarus fasciatus and Echinogammarus ischnus in dreissenid and macrophyte areas in Hatchery Bay, Lake Erie before (1997) and after round goby (2001, 2002) invaded the area. Total amphipod abundance was higher before round goby invasion in both habitats. In mussel beds, E. ischnus abundance was similar or significantly higher than G. fasciatus. In macrophytes, G. fasciatus was significantly more abundant than E. ischnus. In laboratory experiments, we compared amphipod survivorship and growth when fed mussel feces and pseudofeces (F+P) or macrophytes with epiphytes (M+E). Gammarus fasciatus survivorship and growth were higher when fed F+P than M+E. Echinogammarus ischnus showed similar survivorship under both diets, but significantly higher growth when fed M+E than F+P. Therefore inter-habitat differences in food resources cannot explain the abundance patterns observed in the lake. We also estimated the relative vulnerability of G. fasciatus and E. ischnus to yellow perch (Perca flavescens) and round goby (Neogobius melanostomus) predation in laboratory feeding trials using mussel colonies or macrophyte beds as substrate. Both fish strongly preferred E. ischnus in macrophytes, but consumed relatively more G. fasciatus than E. ischnus in dreissenid habitats. Our results suggest that dreissenid establishment may have facilitated the invasion of E. ischnus. However, habitat-specific differences in vulnerability to fish predation may mediate the coexistence of G. fasciatus and E. ischnus by minimizing expansion of E. ischnus to macrophyte areas. Our results also suggest that round goby invasion can alter amphipod abundance patterns in Lake Erie.     

Variability in nitrogen content of submerged aquatic vegetation: utility as an indicator of N dynamics within and among lakes

Submerged aquatic vegetation (SAV) may serve as an integrative proxy of spatial and temporal nitrogen (N) availability in aquatic ecosystems as plants are physiologically capable of storing variable amounts of N. However, it is important to understand whether plant species behave similarly or differently within and among systems. We sampled different SAV species along a nutrient gradient at multiple sites within several lakes to determine variability in C:N ratios and % N content among species, among plants of the same species at a single site, among sites and among lakes. Species respond differently suggesting that not all plant types can be used universally as nutrient proxies. The greatest variability in % N and C:N ratios for Valliseneria americana was observed among lakes whereas for Elodea canadensis it was among sites within a lake and among plants within a site. This suggests that V. americana could be a particularly useful indicator of N availability at larger spatial scales (regional and within a large fluvial lake) but that E. canadensis was not a particularly useful proxy.     

生物滤池串联工艺处理西洋河淀粉废水

为减少西洋河淀粉废水中大量N、P、CODCr进入洋河水库,加剧水库的富营养化,进行了 生物滤池串联工艺处理西洋河淀粉废水的研究。结果表明:系统对淀粉废水中的氨氮、总氮、总磷、 可溶性总磷、正磷酸盐、CODCr均具有较好的去除效果,去除率可分别达到57．7％、58．7％、66．8％、 65．7％、67．4％、75．2％,且对进水浓度变化具有一定的适应性。     

长江宜宾境内地表水中氮磷负荷及来源构成

调查分析了长江上游宜宾境内地表水中N、P状况和各种经济活动对水体TN、TP的贡献。金沙江、岷江N和P指标大多数满足Ⅰ类至Ⅲ类标准限值要求,但进入宜宾城区后水质明显下降。宜宾市各种经济活动中,禽畜饲养活动和居民日常生活是人为氮、磷输入的主要因素。其中,禽畜饲养活动对人为氮、磷输入的贡献逐年增加,在1999～2005年分别从43.54%、66.05% 增至81.37%、57.81%;1999～2005年,宜宾市区的主要经济活动对溶解态无机氮、磷的贡献分别增加了3成和1倍。禽畜饲养活动对水体中氮、磷的贡献超过了非点源农田径流的贡献,同时也是造成研究区水库湖泊富营养化的主要因素。     

多级高浓度活性污泥法脱氮除磷中试研究

多级高浓度活性污泥法在不征地、不增加处理构筑物的情况下,以提高活性污泥浓度为指导思想,对现有城市污水处理厂进行升级改造,达到脱氮除磷的目的。中试研究表明,在试验条件下,出水CODCr为33～43mg/L,去除率92%左右;NH3-N为3～5mg/L,去除率90%左右;TP为1～1.7mg/L,去除率72%左右。系统保证了良好的脱氮除磷效果。     

内蒙古乌梁素海N、P的变化趋势研究

为研究乌梁素海芦苇对水体营养盐的净化作用,采集湖区南部湖水、底泥和芦苇样本,分析了其总氮、总磷的浓度、氮磷比变化趋势。结果表明:湖水由湖心向岸边流动过程中,总氮呈现先增大再减小的变化规律,湖水和芦苇中总磷含量相对平稳,底泥总磷持续增大;总氮浓度的变化范围是1.44~19.31 mg/L,总磷浓度变化范围0.024~0.057 mg/L,氮磷比远远大于16,乌梁素海处于氮过剩的富营养化状态;芦苇等挺水植物的生物量随着营养盐含量的升高而增加,对营养盐具有一定的吸收作用,通过合理的收割芦苇,可以促进乌梁素海氮磷的去除及当地经济的发展。     

Is the destabilisation of lake peipsi ecosystem caused by increased phosphorus loading or decreased nitrogen loading?

Lake Peipsi (3555 km2, mean depth 7.1 m) located on the border of Estonia and Russia is the largest transboundary lake in Europe. L. Peipsi consists of three parts. The shared largest northern part L. Peipsi s.s. (2611 km2, 8.3 m) and the southern L. Pihkva (708 km2, 3.8 m) which belongs mainly to Russia are connected by the river-shaped L. L?mmij?rv (236 km2, 2.5 m). The catchment area (44,245 km2 without lake area) is shared between Estonia (33.3%), Russia (58.6%) and Latvia (8%). Intensive eutrophication of L. Peipsi started in the 1970s. The biomass of N2-fixing cyanobacteria was low at heavy nutrient loading in the 1980s. After the collapse of soviet-type agriculture in the early 1990s, the loading of nitrogen sharply decreased. A certain improvement of L. Peipsi s.s. was noticed at the beginning of the 1990s together with the temporary reduction of phosphorus loading from Estonian catchment while in recent years a destabilisation of the ecosystem has been observed. This deterioration has been expressed mainly as intensive blue-green blooms and fish-kills in summer. Reappearance of blooms has been explained by the decrease in N/P loading ratio due to reduced N discharge while in some periods increased phosphorus loading could have supported this trend.     

Enhanced biological phosphorus removal in RBC with SBR modification.

The rotating biological contactor (RBC) system was operationally modified with a sequencing batch reactor to achieve biological phosphorus removal from a weak domestic sewage along with nitrogen removal. This study utilized three RBC units, of which two units were the main units to remove phosphorus and NH4N and the third RBC unit was used as the storage of wastewater for its minimal effect to the PAO activities in the anaerobic stage during the operation. It was noticed that the biofilm thickness in RBC must be controlled to be less than 1.8 mm in order to achieve more than 70% of P removal with about 60% of N removal. With a settled sewage representing 200 mg/L of COD and 5 mg/L of P, the predicted P content in biofilm was more than 3% and the effluent P concentration was about 1 mg/L. The %P content in biofilm decreased with an increase of influent COD/TP ratios. The COD requirement for anaerobic P release was similar to reported values for the suspended growth system, however, the overall requirement increased with thicker biofilm.     

Low effluent nutrient technologies for wastewater treatment.

The USEPA (2001) water quality nutrient criteria will have a significant impact on water pollution control industry due to stringent N and P requirements. This paper presents an update of findings on successful total N (TN) and total P (TP) technologies being implemented at existing wastewater treatment plants (WWTP) to achieve low TN and TP effluents and some key challenges in achieving lower levels. Plants consistently achieving <5 mg TN/L and < 0.5 mg TP/L were identified from a worldwide literature search and plant data collection. Technology gaps and research needs to improve successful technologies to achieve very low TN and TP effluents are summarised in this paper. The dissolved and colloidal organic N have been identified as major challenges in achieving very low levels of TN. Technical and economic challenges to achieve very low TP effluents include alkalinity deficiency, high chemical usage, high sludge production and lack of sufficient influent BOD for biological P uptake.     

不同碳/氮(C/N)植物体去除废水中氮效果研究

 将枯柳枝、银杏叶、水杉叶、枯竹竿、梧桐叶和枯葡萄藤等6种不同碳/氮(C/N)值含量的植物体浸泡在生活污水中,并测定其对生活污水中氮(N)和磷(P)含量的影响。研究结果表明,除银杏叶外,其余5种植物均有不同的除N能力,其中枯柳枝的除N效果最好,能在40 d内将污水中的总氮(TN)含量从11.09 mg/L降到0.48 mg/L,去除率为95.67%,去除效果最差的水杉叶也可将污水中的TN含量从11.09 mg/L降到1.39 mg/L,去除率为87.47%。所选6种植物均无除P能力,并且在浸泡过程中均有P释放致使污水中P含量升高。     

Multi-Reservoir Operation Planning Using Hybrid Genetic Algorithm and Linear Programming (GA-LP): An Alternative Stochastic Approach

Many models have been suggested to deal with the multi-reservoir operation planning stochastic optimization problem involving decisions on water releases from various reservoirs in different time periods of the year. A new approach using genetic algorithm (GA) and linear programming (LP) is proposed here to determine operational decisions for reservoirs of a hydro system throughout a planning period, with the possibility of considering a variety of equally likely hydrologic sequences representing inflows. This approach permits the evaluation of a reduced number of parameters by GA and operational variables by LP. The proposed algorithm is a stochastic approximation to the hydro system operation problem, with advantages such as simple implementation and the possibility of extracting useful parameters for future operational decisions. Implementation of the method is demonstrated through a small hypothetical hydrothermal system used in literature as an example for stochastic dual dynamic programming (SDDP) method of Pereira and Pinto (Pereira, M. V. F. and Pinto, L. M. V. G.: 1985, Water Res. Res. 21(6), 779–792). The proposed GA-LP approach performed equally well as compared to the SDDP method.     

厌氧生物滤池+生物接触氧化组合工艺处理地表微污染水技术研究

通对通惠河通州段地表微污染水进行水质改善处理技术研究,确定采用厌氧生物滤池+生物接触氧化的组合工艺进行处理,通过试验确定工艺的最佳运行参数为厌氧生物滤池HRT=15 h,生物接触氧化池气水比10,水力停留时间为4 h,回流比为100%。出水中氨氮浓度为0.34 mg/L,总氮浓度为3.2 mg/L,总磷浓度为0.38 mg/L,CODCr浓度为34 mg/L,出水各指标完全满足《地表水环境质量标准(GB3838-2002)》中Ⅴ类水体质量标准,其中总氮浓度远低于课题研究目标的15 mg/L。