潮白河生态补水沿线地下水位变化分析

针对春季潮白河生态补水试验,以潮白河补水沿线地下水监测井数据为基础,对补水沿线地下水变化进行分段和分距离分析,并对影响范围及典型井的地下水动态趋势展开分析:此次生态补水约89％的地表水入渗补给地下,向阳闸以上潮白河沿线周边地下水回升明显,距离河道越近,地下水位响应越快回升越明显,影响区域沿河道向两岸扩展,有利于地下水的生态涵养,促进潮白河流域地下水库的恢复.本研究可为制定科学的生态补水方案提供技术参考.     

潮白河生态补水对周边地下水质影响分析

为探究生态补水对潮白河流域地下水质的影响,选取潮白河补水河段沿线设置地下水监测井开展补水前后地下水质监测,对比分析补水前后水质变化.结果 表明:补水后氯化物、硫酸盐和氨氮浓度下降明显,硝酸盐氮浓度虽有所下降但不明显.氨化物浓度在距河3 km范围内下降最为明显,其他3种指标均在距河3～6 km范围内下降最为明显.生态补水极大改善了潮白河补水河段周边地下水质.     

基于敏感保护目标的那棱格勒河生态需水研究

基于那棱格勒河生态特点,统筹考虑生态基流、鱼类繁殖生长关键期所需河道水量和植被需水高峰期所需短期洪水过程,综合确定河道内生态需水量,并采用流域水量平衡法确定绿洲生态耗水量,同时计算尾闾湖泊需水量。结果表明：河道生态基流10月至次年4月为5.48 m³/s、6—9月为11.82 m³/s,5月河道内生态流量考虑鱼类繁殖需保证11.82 m³/s,6月、9月各需一场不少于5 d、平均流量分别不低于80.0、82.5 m³/s的洪水过程;绿洲区平均生态耗水量为4.54亿m³/a。     

北京市水务系统多措并举 做好防洪排涝工作

<正>2022年,降雨场次集中,时空分布不均。汛期降雨日数61天,平均降雨量392.5 mm,较2021年同期偏少45%,较常年偏少16%。降雨量东多西少,“7·3”“7·27”“8·21”等6场次即超5成;流域来水偏少,河道水势平稳。汛期降雨形成水资源量18.06亿m³,地表水5.78亿m³、地下水12.28亿m³,较2021年少近7成。全市未发生超警洪水过程;地下水位回升,储量持续增加。全市平原区地下水平均埋深16.24 m,较汛前回升1.13 m,比2021年同期回升2.63 m,为连续第7年持续回升,地下水储量比2021年同期增加13.5亿m³。     

潮白河生态补水

正2021年4月30日至5月30日,潮白河实施春季试验性生态补水,累计补水量约2.47亿m~3。通过生态补水回补涵养密怀顺地下水水源地,改善潮白河流域生态环境。水头已于5月18日进入顺义区管段。此次补水预计潮白河将实现1999年以来北京境内全线水流贯通,初步预计补水后潮白河怀柔段干流地下水位回升明显,3 km范围内平均水位回升约7～13 m,     

无人机航测技术在潮白河生态补水中的应用

针对2021年度首次实施的潮白河较大规模试验性生态补水,应用无人机航测技术,对补水区域内的白河、潮河、潮白河潮汇大桥至向阳闸河段、雁栖河及怀河等主要补水河道进行了航测,获取了补水后主要补水河道的水面面积变化、潮白河向阳闸库区三维数字地形,并精确计算了向阳闸库区的河道日入渗量,为科学评估生态补水对潮白河水环境与水生态影响、摸清潮白河地下水回补入渗规律等工作提供了扎实的数据基础.     

地下水回补对密怀顺地下水资源环境的影响分析

密怀顺水源地是北京市重要的地下水源地,为缓解水源地地下水资源量不断减少趋势,2015—2020年累计调水6.5亿m³,利用河道入渗实施地下水回补,回补后区域地下水位升高,地下水资源量增加8.2亿m³;回补后,补水河道周边地下水质依然优良,但再生水排放段地下水质有污染现象,密云、怀柔再生水排放对水源地地下水环境污染风险较大,引温济潮再生水利用工程风险相对较小。本研究为今后地下水回补及水源涵养方案制定与实施提供参考与借鉴。     

潮白河试验性生态补水实施效果分析

潮白河生态补水充分利用了流域内密云水库、怀柔水库及北台上水库等本地地表水和南水北调水,通过白河、潮河、雁栖河、怀河及小中河等5条主要支流向潮白河干流补水,累计补水量2.2亿m3,是一次多水源、多路径、干支流联调的试验性生态补水.本次补水河道通水长度158 km,实现了1999年以来潮白河流域内的首次水系连通,补水后地表水面积较补水前增加了1倍以上,河道周边336 km2范围地下水位出现上升,地下水资源量得到了显著增加,生态环境得到了极大改善,同时还进一步提高了应急调度水平,提升了应急管理能力,补水效益显著,对其他河道生态补水与水资源配置等工作具有很好的借鉴和指导作用.     

坚持“人民至上、生命至上” 我省各地各部门全力防汛迎汛

<正>我省59座大中型水库汛前兴利调度顺利结束7月10日,我省59座大中型水库汛前兴利调度结束,达到预期目的,共预腾汛限水位以下库容5.56亿m³,今年以来完成兴利供水34.16亿m³,其中生活和工业3.82亿m³,农业灌溉和生态补水30.34亿m³。(厅水旱灾害防御处)河北省水利厅有效防范应对7月11日强降雨过程7月11日13时,河北省水利厅针对石家庄、廊坊、保定等中南部地区启动水旱灾害防御Ⅳ级应急响应。     

大通湖生态补水周期及流场分布特征分析

后三峡时期,江湖关系深度演变打破了大通湖“西—北进、东—南出”的水力格局。为了研究变化环境下大通湖的生态补水周期以及大通湖的流场分布特征,基于MIKE 21FM构建了大通湖二维水系水动力模型,模拟了大通湖河湖连通及生态补水工程的水动力条件,研究了不同生态补水流量和不同闸控等6种工况下,大通湖的补水周期和流场形态特征,提出了生态补水效率临界点。结果表明,“单进两出”调度方案流速分布的均匀程度优于“单进单出”方案;非灌溉期生态补水流量为20.48 m³/s,明山电排站为10.5 m³/s时,补水周期为95 d,流速介于0.5～5.0 mm/s的湖面积占总面积的79.96%;灌溉期生态补水流量为28.92 m³/s,明山电排站为10.5 m³/s,补水周期为80 d,流速介于0.5～5.0 mm/s的面积占比为87.82%。     

生物预处理技术在嘉兴地区给水厂的应用比较

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.     

中国部分河口及其近海水域缺氧现象研究

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。     

无资料流域水文预报(PUB计划)研究进展

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。     

Changes in urban stream channels in Zimbabwe

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.     

北京某学校雨水利用设计

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。     

水利高性能计算的进展

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。     

中国内地水库淤积的差异性分析

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。     

Trends in ecological river engineering in Korea

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.     

吉林省2001年汛期降水量趋势预测

本文根据历年6－9月降水量距平值累计曲线和历年6－9月降水量特征值变化，对我省今后汛期全省各地区降水趋势及降水量进行了预测，可供有关部门参考。     

Lake—Wide Seasonal Changes in Limnological Conditions in Lake Michigan in 1976

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.