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1.
徐兵  贺尧基 《给水排水》2007,33(3):7-10
对嘉兴地区主要给水厂近年来应用立体弹性填料、LT型悬浮球填料、YS型悬浮填料、卵石填料等的生物预处理工艺从填料及配套设施、工艺运行参数、运行效果、成本等方面进行了比较.认为弹性填料生物预处理更适用于低浊(50 NTU以下)、低氨氮(1.5 mg/L以下)原水,LT型悬浮球填料生物预处理适用于低中浊(100 NTU以下)、低中氨氮(2.5 mg/L以下)原水,YS型悬浮填料生物预处理及"SAF"滤池对低浊、中高氨氮(2.5 mg/L以上)原水有较好的适应性.最后探讨了弹性填料存在的短流、积泥,悬浮填料存在的部分填料流化不均匀,富氧的生物工艺单元内水生动物泛滥等问题.  相似文献   

2.
无资料流域水文预报(PUB计划)研究进展   总被引:14,自引:1,他引:13  
无资料流域水文预报,简称为PUB(Predictions in Ungaugecl Basins),从2003年7月开始成为国际水文科学学会新的国际水文十年计划主题.文中首先简述了PUB计划的主要研究内容,然后回顾了国际和国内已有的PUB研究进展,最后展望了对水文学发展有重要意义的几个PUB前沿研究,包括不确定性研究、对水循环各个环节因素的预报和对无资料流域水文过程的预报。  相似文献   

3.
Since the late 1980s, the use of commercial fertilisers in most Eastern European countries has decreased at an unprecedented rate. We examined the impact of this dramatic reduction in agricultural inputs on concentrations of nutrients in four rivers in Eastern Europe: the Emajogi and Ohnejogi (Estonia), the Daugava (Latvia), and the Tisza (Hungary). Time series of nitrate (NO3-N) and phosphate (PO4-P) concentrations and data on runoff were selected to represent catchments with substantial areas of agricultural land and available time series of sufficient length and frequency. The study period was 1987-1998. We detected downward trends in nitrate-N and phosphate-P in only two of the four rivers. Our results imply that the response to the extensive decrease in agricultural intensity since the late 1980s has been slow and limited in many rivers. Corresponding results in the literature are inconclusive and comprise several examples of both decreasing and non-decreasing nutrient concentrations. Our findings, along with similar data from other studies, indicate that large cuts in nutrient inputs do not necessarily induce an immediate response, particularly in medium-sized and large catchment areas. Moreover, the difference we noted between nitrogen and phosphorus suggests that factors other than reduced fertiliser application influenced the inertia of the water quality response.  相似文献   

4.
《小水电》2003,(2):1-3
一、中共中央中发[2002]2号文件将农村水电列为国家重点支持的农村中小型基础设施。中共中央中发(2002]2号文件《中共中央、国务院关于做好2002年农业和农村工作的意见》,将农村水电列为“周期短,见效快,覆盖千家万户,促进农民增收的效果更显著”的农村中小型基础设施,要求放在更加重  相似文献   

5.
深圳河支流新洲河属雨源型河流,因污染而采取全线截排污水整治.在上游河道内利用生物飘带技术处理低浓度污水,处理达标后,作为河流生态水源.在中游将截排污水引入自然循环方式污水处理系统,处理达标后作为河道补水.下游利用射流清淤配合利用天文大潮进行水体交换,达到消除黑臭水体,维持河道水景观的目的.介绍新洲河水环境综合整治采用的几项关键技术的设计原理及应用效果.  相似文献   

6.
对长江、珠江等河口及其近海水域缺氧现象与影响因素进行研究,结果表明,主要分布于长江与珠江河口及其邻近海域的缺氧现象,夏季(6—8月)达到最盛,秋冬季消失;长江口的缺氧区域主要位于30.75°N~32°N,122.5°E~123.25°E附近海域,具有南北2个缺氧中心;珠江口缺氧程度相对较轻,缺氧区域主要在广州黄埔区河段至虎门水域和伶仃洋;辽河、钱塘江、海河等河口区域也时而出现零星的缺氧现象;水体缺氧受控于多项环境要素,物理层化作用是缺氧产生的最初诱因之一,陆源污染物的分解则是重要的耗氧负荷;各河口区特征各异,潮汐、洋流、营养盐、叶绿素a等要素对缺氧区的范围、程度和持续时间影响程度不一。  相似文献   

7.
《小水电》2004,(3):1-2
一、党中央、国务院重视农村水电,部署启动小水电代燃料建设。中共中央中发〔2 0 0 3〕3号文件要求对农村水电等农村中小型基础设施扩大投资规模,充实建设内容。同时部署启动小水电代燃料建设。胡锦涛总书记、温家宝总理多次讲话要求加强农村水电建设。国务院国发〔2 0 0 3〕16  相似文献   

8.
洋河水库是我省重点病险库之一,1998年12月实施除险加固工程。工程建设过程中在科研、设计、施工及管理等方面取得了可喜的成果。通过研究分析,因地制宜地选择了天然建筑材料,合理确定了施工方案,有效保证了施工质量,节约了工程投资。  相似文献   

9.
Hyoseop Woo   《Journal of Hydro》2010,4(4):269-278
Ecological river engineering can be defined as the design and implementation of river works and river restoration works for the benefit of human society. It also guarantees the sustainable ecological functions of a river, such as its habitats and self-purification of its water. It is currently in the beginning stages in Korea, utilizing scientific knowledge on the processes of aquatic ecosystem degeneration and a methodology for solving the ecological problems in artificially altered rivers currently under development. The changes in river management and work practices in Korea may be best explained with a chronologically progressing sequence of ‘Natural’, ‘Disaster-prevention’, ‘Occupied’, ‘Park’, and ‘Close-to-nature’ rivers. Since the 1960s, the focus on river management and work has shifted from flood control only, to both flood control and riverine habitat conservation and restoration. Five research topics have been selected for this article, and the progress of each research area is briefly described with a representative picture in each topic. They are as follows: (1) flow resistance due to vegetation, (2) environmental flow, (3) floodplain vegetation modeling, (4) small dam removal, and (5) river restoration. For the future prospects of research on ecological river engineering in Korea, a necessity of further research on floodplain vegetation recruitment and succession, which can explain the so-called ‘white river’ and ‘green river’, is underlined, among others. Finally, two ongoing large research programs on river ecosystem restoration, of which are sponsored by the Government of Korea, are briefly introduced, followed by the introduction of a near-prototype experiment facility recently completed mainly for research on ecological river engineering.  相似文献   

10.
王科 《四川水力发电》2002,21(1):59-60,64
介绍了映秀湾水力发电总厂结合季节性安全大检查开展安全性评价的过程,提出存在的主要问题及采取的对策措施,为安全性评价结合季节性安全大检查开展作了实践性探讨。  相似文献   

11.
1998年长江流域洪水灾情   总被引:5,自引:0,他引:5  
1998年长江全流域的大洪水,使整个流域遭受了建国以来少见的自然灾害,分析造成洪灾的主要原因为:暴雨频繁,且降雨强度大,提防隐患多,且防洪标准不高,洪不来临时,洲民垸难以适时弃守;山洪山地灾害突发性强,提出今后防洪减灾的措施,提高堤防的抗御能力,尤其要加快对坝基的处理和堤身加固;加快蓄滞洪区的安全设施的建设,洲滩民垸应按防洪规划时弃守以利于行蓄洪;加快中小城镇的防洪工程建设;加强山地灾害的防御。  相似文献   

12.
荧光原位杂交技术检测污水处理中微生物的生理生态   总被引:3,自引:0,他引:3  
近年来.对污水处理的研究已经从简单研究污水处理的表征现象转移到更深入地研究活性污泥内部微生物种类及其特性。荧光原位杂交技术是一种微生物生态的研究技术,在测定过程中不破坏细胞、保持细胞形态完整,能够真实反映在自然环境下微生物的形态结构及分布状态。该文综述了荧光原位杂交技术的原理、实验步骤和影响因素及其在污水处理微生物生态学检测中的应用。包括利用荧光原位杂交技术研究硝化细菌和除磷细菌,而且还探讨了该技术在实际应用中存在的问题并肯定了其与分子生物学技术相结合的发展方向。  相似文献   

13.
中国内地水库淤积的差异性分析   总被引:7,自引:0,他引:7       下载免费PDF全文
为了解水库的淤积现状,根据115座具有代表性的中国内地水库淤积资料,对这些水库按类型和区域进行统计分析,结果表明,中小型水库比大型水库淤积严重,不同流域水库淤积的空间差异明显,黄河中下游地区水库淤积比例最大,西南地区水库年均淤积率最大。截止到2003年,根据代表性水库淤积的计算结果推算出中国内地水库的平均淤积比例约为20%,库容年均淤积率为0.76%,相当于每年损失1座库容近42.3亿m3的超大型水库。  相似文献   

14.
水利高性能计算的进展   总被引:1,自引:0,他引:1       下载免费PDF全文
针对水利信息化对精细模拟与高性能运算提出的愈来愈高的要求,在简单介绍高性能计算的硬件、软件环境及其在水利上的几个应用实例后,着重介绍了并行有限元法、并行边界元法的一些进展以及网格技术的最新进展。指出从网络到网格是高性能计算发展的最新方向,应以网格平台支持、促进水利信息化进程。  相似文献   

15.
Although channel change has been documented downstream of urban areas there have been few previous studies which have focused upon the spatial variation of erosion and upon examples of such channel change in tropical areas. In the Avondale stream basin, which includes part of Harare the capital of Zimbabwe the way in which the channel network has evolved from the extensive dambo system in the period 1891 to 1984 is reconstructed showing that drainage density which was initially between 0.35 and 0.80 km km?2 has increased to 3.15 km km?2 including stormwater drains. Characteristics of erosion of the modified urban channels are described and the downstream reaches indicate an average channel widening of 1.7 times involving average rates of bank erosion of 0.33 m per year. Peak discharge is estimated from channel characteristics to be increased to two times former values and it is concluded that channel type and the relationship of channel change to the accommodation of peak discharges requires further research.  相似文献   

16.
Data collected on lake-wide cruises in 1976 were used to study seasonal and vertical variations in water temperature, transparency, chlorophyll a, and nutrients in Lake Michigan. Data were analyzed according to subsets corresponding to the northern and southern open lake. Comparisons (t-tests) of data from the open lake indicated that the average water temperature was cooler and average water transparency was greater in the northern lake than in the southern, but with the exception of total phosphorus, average nutrient concentrations did not differ between the northern and southern parts. It was found that physical-chemical characteristics of nearshore and Straits of Mackinac stations differed significantly from open lake stations. Seasonal phytoplankton dynamics in the open lake were related to seasonal and vertical changes in silica and nitrate nitrogen. The spring phytoplankton bloom occurred before the lake was strongly stratified thermally. After thermal stratification was well developed, epilimnetic concentrations of chlorophyll a decreased, probably due to some combination of nutrient limitation and zooplankton grazing, and maximum chlorophyll a concentrations were found below the thermocline. Epilimnetic silica concentrations decreased after thermal stratification and diatoms were replaced in the phytoplankton assemblage by green and blue-green algae in late summer. Total phosphorus averaged only 8 μg/L on a lake-wide basis and thus only small but significant reductions in absolute concentration can be expected from phosphorus control programs. However, over a period of several years, these small reductions in concentration may be difficult to verify from total phosphorus measurements which have relatively large sampling errors and variances.  相似文献   

17.
北京某学校雨水利用设计   总被引:3,自引:0,他引:3  
以北京市某中学为例,介绍一种学校雨水利用的方法。根据校区水量平衡计算结果,对利用校园内汇集的雨水作为冲厕、绿化和景观用水等进行设计;采取相应的技术措施,对雨水径流的污染进行控制,保障所利用雨水的水质达到要求,并采用生态净化的方式,使学校景观水体循环起来。虽然雨水利用工程投资较高,但其社会和环境效益显著。  相似文献   

18.
为促进我国水库大坝土工膜防渗工程的健康、快速发展,对其发展历程进行回顾、梳理。总结了将土工膜用于水库大坝防渗的优点,即防渗性能高、适应变形性强、施工方便、质量易于控制、工程整体造价低。指出尽管已建成的大中型土工膜防渗工程运行正常,但土工膜仅在我国中小型工程中应用广泛。通过对比国内外水库大坝土工膜防渗工程的发展现状,分析了国内外发展差距较大的原因,即缺乏国际交流的外部环境,缺乏自主研发的内部动力,以及缺乏规范的适时认可。认为随着建设经验和技术储备的积累,科技成果传播的畅通迅速,从业人员对该项技术的认识深入,我国水库大坝土工膜防渗工程具有较大的经济、社会效益潜在优势。  相似文献   

19.
This paper identifies and analyses the transaction costs involved in the implementation of a tradable water right system in the Heihe River basin in northwest China. Both primary and secondary data were used to achieve the objectives. The results indicate that water markets in the Heihe River basin are not popular. However, transaction costs were not the primary source of market dysfunction. In some cases transaction costs were high enough to block water trading while in other cases transaction costs were very low and insufficient to limit the emergence of water markets.  相似文献   

20.
光耀华 《水力发电》1999,(5):5-8,14
广西地壳经历了元古代-早古生代地槽,晚古生代-中古三叠世准地台和晚三叠世-第四纪陆缘活动带3大发展阶段,碳酸盐沉积主要在前2个阶段。由于碳酸盐岩广泛分布,致使广西成为中国典型的岩溶地区。广西水力资源蕴藏量的61%位于岩溶地区。并从实践中总结了总结了广西主要江河岩溶发育的基本规律和水电建设的经验,提供了工程规划设计了所必须的基本资料和评价依据。为广西电力水利建设作出了贡献。  相似文献   

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