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引黄灌区档案是引用黄河水活动中供水生产、工程管理、灌溉试验、工程规划设计等工作的全过程和最终结果的真实记录,作为引黄灌区建设成果与管理技术的重要储备形式,是知识形态的生产力,可称为引黄灌区档案信息资源。当前,东营市的王庄、胜利、麻湾和宫家等引黄灌区先后完成了节水改扩建工程,做好引黄灌区档案管理工作,推动灌区档案工作向正规化、科学化、现代化的轨道发展,使灌区档案管理工作发展到一个新的层次,服务于灌区建设与管理,是值得探讨和研究的问题。 相似文献
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文章以中牟县杨桥灌区配套与节水改造工程为例阐述了灌区在项目建设中,实行了项目法人责任制、采取招标投标制、建设监理制和政府监督制度,为工程顺利有序进行提供了有效保障。随着灌区设施的配套不断完善和各项改革的不断深入,从提高灌区管理水平、建立高效的运行机制着手,实现灌区建设与管理的科学化、规范化,使灌区的经济效益和社会效益同步增长,实现灌区的可持续发展。 相似文献
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随着市场经济的发展与不断完善,灌区原有的管理体制与运行机制已不能适应灌区现代化管理的需要,必须建立符合社会主义市场经济要求的灌区管理体制和运行机制,才能实现灌区的可持续发展。 相似文献
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大中型灌区是农业发展的基石,搞好灌区管理是实现灌区良性循环的关键。管理是一门科学。灌区管理的任务就是理顺灌区与外部的各种关系,充分调动灌区内部各方面的积极性,有效地用好灌区资源和工程设施,为用水户提供优质高效的服务,促进农业增收增产,增加农民收入,改变生态环境,使灌区良性运行,实现可持续发展。 相似文献
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淠史杭灌区工程续建配套与节水改造正在进行,工程条件得到改善,管理体制进一步理顺;但由于灌区水资源总量有限,管理技术相对滞后,限制了灌区效益的发挥,因此,实现信息化管理将成为淠史杭灌区提高水资源利用效率,实现可持续发展的重要内容。2002年淠史杭灌区被列入全国信息化建设试点灌区之一,灌区信息化建设正逐步展开。 相似文献
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Cheryl R. Dykstra William T. Route Kelly A. Williams Michael W. Meyer Rebecca L. Key 《Journal of Great Lakes research》2019,45(2):252-262
We analyzed concentrations and trends of DDE, total PCBs, and mercury in bald eagle (Haliaeetus leucocephalus) nestlings at six study areas in the upper Midwest, 2006–2015, and long-term trends at two Lake Superior sites, 1989–2015. Eaglet plasma from the Apostle Islands in Lake Superior had the highest concentrations of DDE (geometric mean [GM]?=?10.6?μg/L), and DDE concentrations decreased at 5.8% per year across the region from 2006 to 2015, and at 5.5% per year at Lake Superior sites from 1989 to 2015. Concentrations of the sum of 75 PCB congeners (ΣPCB75) were highest at Pools 3 and 4 of the Mississippi River (GM?=?114.8?μg/L) and did not decline significantly region-wide (all study areas together) between the years of 2006 and 2011. However, at Lake Superior, ΣPCB75 declined from 1995 to 2011 along the south shore at 3.6% per year, with a non-significant decline at the Apostle Islands. Concentrations of mercury in nestling breast feathers were highest at the upper St. Croix River (GM?=?6.66?μg/g wet weight). At Lake Superior study areas, mercury declined at 1.6% per year from 1991 to 2015; however, from 2006 to 2015 we found no significant trend at one of these same study areas and mercury concentrations apparently increased at two study areas. Mean concentrations of contaminants were below levels associated with significant impairment of reproduction at all sites and mean reproductive rates were?>?1.4 young per nest. However, increasing concentrations of mercury in some areas, combined with relatively high concentrations at some nests, suggest that continued monitoring of mercury should be a management priority. 相似文献
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Zhen Wang Fei Cheng Gang Hou Yiqing Song Arunjith Thundiparambil Sathrajith Songguang Xie 《河流研究与利用》2019,35(7):1053-1061
Dam cascades have been a major threat to fishes of the upper Yangtze River. The remaining lotic river segment of the upper mainstem between the Xiangjiaba Dam (XJD) and the Three Gorges Reservoir (TGR) may serve as a critical refuge for endemic fishes. We investigated distribution of ichthyoplankton Botia superciliaris, an endemic species, at three sections preimpoundment and postimpoundment of the XJD, that is, Yibin (close to the XJD), Zhuyang (in the middle of the segment), and Mudong (in the tail of the TGR). Preimpoundment of the XJD, larvae occurred in all three sections, and their abundance tended to be highest at Yibin and lowest at Mudong. Postimpoundment, larval abundance dramatically decreased in all three sections. In particular, no larvae were found at Yibin, and larval abundance tended to be higher at Zhuyang than at Mudong. Eggs were collected from all three sections, and those from Zhuyang accounted for over 90% of the total. Initiation of egg occurrence at Yibin was approximately 1 month later than at Zhuyang and Mudong. Water temperature was lower, and water transparency was higher at Yibin than at Zhuyang and Mudong postimpoundment. We suggest that the decrease in abundance and delayed presence of ichthyoplankton at Yibin postimpoundment of the XJD reflected the impact of upstream dam discharge and that the lower abundance of ichthyoplankton at Mudong compared with Zhuyang both preimpoundment and postimpoundment of the XJD reflected the influence of inundation by the TGR. We recommend that the river sections around Zhuyang become high‐priority conservation areas 相似文献
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针对黑龙江西部风沙土区多风少雨,春旱严重,粮食产量及作物水分利用效率低等实际问题,于2009年在黑龙江省杜蒙县进行了交替隔沟灌溉条件下的玉米耗水规律及其产量的试验研究,为当地节水农业的发展提供必要的理论与技术支撑。试验表明,玉米整个生育期内拔节—抽雄期耗水量最大,日耗水量在抽雄—灌浆期最大。交替隔沟灌溉在适宜的灌水量水平下,产量增加显著。本试验中产量最高时,生育期灌水定额分别为苗期325 m3/hm2、拔节期300 m3/hm2、灌浆期400 m3/hm2。各生育期耗水量分别为播种—苗期38.92 mm、苗期—拔节91.14 mm、拔节—抽穗100.00 mm、抽穗—灌浆65.49 mm、灌浆—乳熟53.28 mm、乳熟—收获33.35 mm。 相似文献
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现有拱坝设计规范的温度荷载假定上游库水位固定在正常蓄水位,而实际上游库水位在运行中是不断变化的。研究表明,固定水位与变化水位条件下的温度荷载存在较大的差异。以西南某拱坝为例,对同一高程处温度年变化采用傅立叶级数展开,开展变化水位下拱坝温度荷载的研究,对比分析了固定水位和变化水位下两种温度荷载及温度荷载作用下应力与变形的差异。结果表明:变化水位下温度荷载同固定水位下温度荷载的差值随深度的增加基本呈先增大后减小的趋势。在其他荷载一定时,固定水位温度荷载作用下的变形值稍大于变化水位温度荷载作用下的变形值,最大应力均要大于变化水位温度荷载作用下的最大应力。 相似文献
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对小浪底水库2000-2006年的运用效果进行了分析,结果表明:①自1999年10月至2006年10月,小浪底水库库区累计淤积量为21.27亿m3,其中干流淤积量为18.01亿m3,支流淤积量为3.26亿m3,利津以上河段累计冲刷泥沙13.23亿t,黄河下游河道主河槽最小平滩流量已由2002年汛前的1 800 m3/s增大至3 500 m3/s左右;②2002-2006年,水库实施了5次调水调沙,均实现了下游主槽的全线冲刷;③经三门峡、小浪底等水库联合调度,有效削减了洪峰流量,减小了下游河道发生漫滩洪水的几率,减轻了滩区群众淹没损失;④小浪底水库的合理调度不仅确保了特枯水年黄河下游不断流,改善了下游河道生态环境,而且多次为外流域供水;⑤1999-2006年,小浪底水电站累计发电量为255.92亿kW·h. 相似文献
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低地应力区地下洞室开挖后围岩位移二维离散元数值模拟 总被引:3,自引:0,他引:3
以西北某水利工程地下洞室为例,对低地应力状态下洞室开挖后围岩位移变化及其相应特征,采用了二维离散元法进行数值模拟研究,结果表明:低地应力区地下洞室开挖后围岩位移主要发生在拱顶位置,而发生在侧壁水平位置上的围岩位移量则明显不及前者,这说明低地应力区地下洞室开挖后围岩变形破坏主要发生在洞顶垂直方向,侧壁水平方向围岩变形破坏规模和强度均不及前者。 相似文献