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我国北方干旱地区水资源短缺,严重制约了经济社会的发展,生态环境形势严峻;同时水资源利用效率及效益低下,因此大力推行节水、建设节水型社会成为北方干旱地区可持续发展战略的重要保障。本文以山东省聊城市为代表,分析了该市水资源特点及用水现状,分析了需水总量控制在建设节水型社会中的作用和地位,提出了聊城市建设节水型社会的思路、目标和措施。 相似文献
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建设节水型社会是解决我国水资源供需矛盾的最根本最有效的战略举措。节水型社会建设迫切需要一套科学的方法技术体系来支撑。文中根据我国北方干旱地区特殊的水资源及用水背景,提出了五大技术体系来支撑山西省节水型社会建设。五大技术支撑体系包括:以水权管理为核心的水资源总量控制与微观定额管理体系、与区域水资源承载能力相协调的经济结构体系、满足节水型社会建设要求的水资源调配与综合信息管理体系、与水资源优化配置相适应的节水工程与技术体系和与全面节水管理相配套的制度保障体系。 相似文献
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宁夏回族自治区是水资源严重短缺的省区之一,人均水资源可利用量664 m3,水资源供需矛盾成为宁夏经济社会发展的重要制约因素。作为第一个省级全国节水型社会建设试点,近年,宁夏结合自身情况,确定节水型社会建设总体思路并积极推动,取得了显著成效和宝贵经验,为西北同类干旱地区节水型社会建设提供参考。 相似文献
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节水型社会建设是实现水资源高效利用的前提条件,是迈向环境友好型社会的重要战略部署.基于对当前我国节水型社会建设实践和经验的研究,从理解节水型社会的建设意义着手,阐述了当前我国节水型社会建设中存在的关键问题,并结合未来的发展需求探讨了加强节水型社会建设的具体措施,旨为我国水资源可持续利用提供新思路和新方法. 相似文献
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吕梁市水资源开发利用中面临的水资源供需矛盾日益突出、传统的用水结构难以适应现代化建设的需要、水资源利用效率不高、水环境承载能力不足等4个主要问题,本文针对性地提出吕梁市节水型社会建设目标,以及节水型社会建设的主要内容。 相似文献
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通过对兖州市水资源现状及节水型社会初步建设进行分析,指出节水型社会建设中所取得的成绩及存在的问题和不足,并就下步围绕如何建设节水型社会,提出一些观点和措施:工农业及城市生活节水型载体建设的推广;依靠科技力量,助推节水型社会快速发展;建立健全水资源管理制度和各种节水规划;做好节水型社会建设的宣传发动工作。 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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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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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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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
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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