共查询到20条相似文献,搜索用时 62 毫秒
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通过对20世纪80年代以来滹沱河山前段的地表水和地下水环境劣变特征分析,阐明了山前拦地表水和山前平原超采地下水对水环境影响的后果,并以大量实测资料为依据论证了被疏干地下含水介质空间的地下调蓄可利用性,系统阐述了研究区地下调蓄的基本条件和潜力,提出了南水北调客水利用地下调蓄条件发挥更大效益的建议。 相似文献
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在总结我国人工地下水回灌类型及地质条件的基础上,对再生水地下调蓄利用的必要性和可行性进行了分析,结合即将颁布的再生水地下水回灌水质标准,提出实施再生水地下调蓄工程配套的再生水处理工艺和应遵循的准则。 相似文献
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黄土地区调蓄水池的新建越来越多,其渗漏特性、渗漏计算及防渗处理问题亟需解决。通过对陕北定边县陡沟调蓄池黄土库区地质条件说明、渗漏类型识别、渗漏原因分析及渗漏方法计算,认为黄土地区调蓄池渗漏损失量主要以前期对库底及库周土层的饱和需水量为主,渗漏类型主要为临时渗漏,而后期土层饱和后渗漏即永久渗漏量对库区蓄水影响不大。进而提出通过引水工程取用临时渗漏量,对地下水取用困难的永久渗漏型水库进行防渗处理。 相似文献
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朱海燕 《河北水利水电技术》1996,(4):13-16
引江中线工程近期分配河北省水量为37.56亿m^3,为充分利用引汉水,需对引汉水与当地地表水、地下水联合调算。本文研究供水区内城市、工业、农业的供水状况及库、洼补偿调节与调蓄等情况。 相似文献
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某水电站库首单薄分水岭岩溶渗漏问题探讨 总被引:1,自引:0,他引:1
依据大量实际资料,论述了某水电站库首左岸单薄分水岭的岩溶发育特征、控制因素、水文地质条件及岩溶发育规律,结合物探综合测井和地下水长观等综合研究手段,对库首左岸单薄分水岭岩溶渗漏问题进行了初步评价,对以后施工的左岸防渗处理具有一定的参考价值。 相似文献
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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
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Changes in nutrient levels in some Eastern European rivers in response to large-scale changes in agriculture. 总被引:3,自引:0,他引:3
P St?lnacke S M Vandsemb A Vassiljev A Grimvall G Jolankai 《Water science and technology》2004,49(3):29-36
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
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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
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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
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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
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李广杰 《水科学与工程技术》2001,(5):7-8
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