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1.
Larval fishes were sampled in the Milk River, Missouri River drainage, Montana from May to August 2002, 2003 and 2004 to describe temporal spawning distribution in relation to spring discharge. Total larval catch‐per‐unit‐effort (CPUE) in 2002 (28.9 fish/100 m3) was an estimated 29 times greater than in 2003 (0.99 fish/100 m3) and 16 times greater than in 2004 (1.78 fish/100 m3). In 2003 and 2004 more than one third of the total catch occurred before 12 June whereas in 2002, only 5% of the total catch occurred before 12 June. Marked differences in larval species composition were also observed between years, suggesting that a later peak in discharge may benefit some species and an earlier peak others. In 2002, when flows peaked later (at 77 m3 s?1), common carp Cyprinus carpio represented 37% of the total larval catch. Common carp were proportionally less abundant in 2003 (7.2%) and 2004 (1.4%) than in 2002. In 2004, when flows peaked (at 163 m3 s?1) 32 days earlier than in 2002 but only 15 days earlier than in 2003 (at 73 m3 s?1), shorthead redhorse Moxostoma macrolepidotum and suckers Catostomus sp. were the numerically dominant taxa. These results indicate that the timing, not necessarily the magnitude, of peak spring discharge may influence spawning success in the lower Milk River, as indicated by larval fish catches. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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We examined inter‐habitat variation in benthic macroinvertebrate assemblages in the 180‐km Garrison Reach of the Upper Missouri River, North Dakota (USA) in 2001–2003. The Garrison Reach is unchannelized with a mostly rural setting. Flows are regulated by Garrison Dam. We sampled benthos from three habitats defined a priori: channel, shoreline, and backwater. Benthic assemblages were different in each habitat. Average Bray‐Curtis dissimilarity in assemblage composition ranged from 89% for backwater versus channel habitat to 70% for backwater versus shoreline habitat. There were distinct intra‐habitat groups within a priori habitats: channel assemblages included moving‐sand assemblages and other‐substrate channel assemblages; backwater assemblages included connected (to the river channel) and unconnected backwater assemblages; shorelines assemblages varied between natural (unprotected) and riprap (rock revetment) shorelines. Abundance and taxa richness were lowest and spatial variability highest for moving‐sand channel assemblages. Abundance was highest in backwaters. Taxa richness in backwaters and along channel shorelines were similar. Assemblages in all three habitats were dominated by Nematoda, Oligochaeta and Chironomidae. Taxa in these groups comprised at least 80% of mean abundance in all three habitats. Taxa that discriminated among habitats included the psammophilic chironomid Chernovskiia for moving‐sand channel substrates versus all other habitats; Hydroptila (Trichoptera) for riprap vs natural shorelines, Aulodrilus (Oligochaeta) for connected versus unconnected backwaters; and Nematoda for backwater versus channel and shoreline versus channel. Based on overlap patterns in benthic assemblages among habitats, we concluded that sampling main channel shorelines should also capture much of the natural and stressor‐induced variation in connected backwater and channel habitat exclusive of moving‐sand channel habitat. Published in 2006 by John Wiley & Sons, Ltd. 相似文献
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长江中游是洪灾最为严重的地区，其中尤以荆江河段最为严重，长委会以往对洪水预报和分蓄洪方案的计算多采用水文学的方法，为适用实时分洪调度决策的更高要求，１９９０年水利部和长委会领导决定先建立一个自宜昌至大通的防洪实时调度整体数学模型，其中包括洞庭和鄱阳二湖水系，研制工作从１９９１年开始，并对宜昌至汉口段作了具体计算，经过１９９２年汛期实时预报工作的检验，又经过１９９３年对１９６９年洪湖溃口分洪进行重演 相似文献
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Abstract This paper analyzes recent developments regarding Missouri River management and water use, and the potential for an emerging inter-basin water dispute involving the Great Lakes. It is suggested that revisions to the U.S. Army Corps of Engineers' master manual for the Missouri River and increasing efforts to put Missouri River water to beneficial use in support of economic growth present the prospect of low water levels in the Mississippi River. With a history of looking to the Chicago diversion as a source for augmenting flows in the Mississippi River, it may yet again prove to be an irresistible temptation. The institutional capacity for managing such a water dispute seems surprisingly weak. The direction suggested is that mechanisms should be installed to ensure that Great Lakes water remains in its basin, consistent with watershed management practices. The recent efforts by the Great Lakes states and provinces represent an important development in this direction. It is further suggested that demand pressures in the Missouri River should be met through a similar commitment, potentially through a water sharing arrangement on the Missouri River, something which could be encouraged in part by ensuring stricter controls on the Chicago diversion. 相似文献
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长江整体防洪标准低，洪涝灾害成为制约本流域国民经济发展的重要因素。从多年的防汛实践看，加强综合治理、实施“标本兼治”、开拓分蓄洪区建设新思路、大力加强非工程防洪措施等，提高长江中下游抗御洪涝灾害的能力。 相似文献
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长期以来，长江洪水预报一直采取手工作业方式，为了提高洪水预报的实时性、准确性和可靠性，长委水文局预报处与其他单位共同研制出长江中下游洪水联机实时预报系统，于１９９５年投入运用。该系统由预报作业、水情检索和系统管理三部分构成，融合了先进实用的模型理论、计算机信息技术和专家经验。实际运用中，采用预报实时校正的方法，由预报员对预报值进行比较分析后确认。系统试用结果表明：由于将计算机系统与预报员作业连为一体，提高了成果质量和工作效率，将实时跟踪能力强的ＣＲＦＰＤＰ模型投入作业运行，提供了分析预报结果合理性的有力工具；利用预报员的经验，注重对模型预报值的可靠性和可能的偏差方面分析是非常必要的。另外针对系统数据库管理问题，提出了研制新的洪水预报系统的设想。 相似文献
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Recolonization of Pacific lampreys Entosphenus tridentatus into historically used freshwater habitats in the United States Pacific Northwest was evaluated in the White Salmon River basin after removal of Condit Dam. Pacific lamprey population declines are of concern, and passage barrier removal is often recommended for conservation. Condit Dam on the White Salmon River in Washington was a complete barrier to fish migrating upstream for nearly 100 years, was breached in 2011, and was removed by 2012. Distribution of larval Pacific lampreys was estimated before and after removal of Condit Dam using either backpack or deepwater electrofishing. Larval detection probabilities were calculated for the basin, and sample efforts were refined to ensure at least 80% confidence that larvae were absent when not detected. Pacific lampreys were not present upstream of Condit Dam before it was removed but were present in areas downstream of the dam. After dam removal, Pacific lamprey larvae were collected upstream of the former dam site from four reaches of the mainstem White Salmon River, indicating a recent recolonization event. Pacific lampreys were absent from the river mouth area before the dam was removed but were found in newly created habitat at the mouth after dam removal. Pacific lampreys naturally recolonized the White Salmon River basin within a few years after dam removal. Removing dams and providing passage opportunity can allow Pacific lampreys to distribute into vacant areas and may help reverse population declines. 相似文献
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Geng Li Caroline M. Elliott Bruce C. Call Brandon J. Sansom Robert B. Jacobson Binbin Wang 《河流研究与利用》2023,39(9):1857-1874
River turbulence is spatially variable due to interactions between morphology of rivers and physical mechanics of flowing water. Understanding the variation of turbulence in rivers is important for characterizing transport processes of soluble and particulate materials in these systems. We present an exploratory effort to understand ecologically relevant flow patterns using measurements of mean flow and turbulence in a highly engineered river channel around an island in the lower Missouri River. Specifically, the profiles of mean river velocities were investigated to examine the logarithmic relation and associated parameters, including shear velocity and bed roughness. Turbulence intensity and Reynolds shear stress were compared with classic open-channel profiles and previously reported river data in the hydraulics literature. With the capability of pulse-to-pulse coherent Doppler velocity profiling in high spatial resolution, we estimated the profiles of turbulence dissipation rate using resolved one-dimensional velocity spectra. These measurement data allow us to examine the validity of turbulence production-dissipation balance and the classic open-channel profiles of turbulence statistics, including turbulence intensity, Reynolds shear stress, dissipation rate, and eddy viscosity. The field data show a strong variation of turbulence profiles in close vicinity of the river island. In shallow water depths close to the island, turbulence is substantially enhanced in comparison with classic open-channel profiles. Such turbulence enhancement is likely attributed to non-uniformity of the flow structures. 相似文献
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图形工作站以其强大的图形处理功能得到日益广泛的应用。对于水文气象预报领域中所处理的信息数据，最直观的表示方法是图形，普通微机在图形处理方面不能满足水文气象预报的要求，而使用图形工作站则能使数据和图形密切结合。通过介绍图形工作站的基本构成及其在水文气象预报中的一些应用成果，以展示图形工作站在水文气象预报应用中的广阔前景。 相似文献
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洞庭湖区防洪问题研究 总被引：3，自引：1，他引：3
自解放以来，洞庭湖区围湖垦殖、泥沙淤积，湖区面积衰减1727km^2。湖容萎缩126亿m^3。湖区洪水位抬高1．0m以上。下荆江裁弯后，三口萎缩加速，江湖关系发生重大变化，长江城螺河段河床淤积，水位升高，洞庭湖出口泄流不畅，湖区洪水位进一步抬升，防洪形势严峻，洪灾损失严重。解决湖区防洪问题的关键是减少超额洪水来量及降低城陵矶河床高程及水位，扩大调洪湖容，近期难以实现。采取在退田还湖的同时挖湖筑堤造台，提高防洪标准，让老百姓安居乐业；堵支并流与疏通河道，扩大调洪能力；实施干支流水库联合调度防洪及预留必要的设施完备的分蓄洪区，乃是解决洞庭湖区防洪的当务之急。 相似文献
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塔里木河流域是南疆的生命河、母亲河,然而流域内洪灾频发,对流域防洪对象造成极大威胁。以塔里木河流域为研究对象,从流域径流、工程措施与非工程措施三个方面分析了流域洪灾成因;分析了2022 年典型洪水的洪灾成因、洪水调度过程,总结了经验启示,提出应对措施。研究结果对于提高流域防洪能力,保护下游防洪对象安全具有重要的指导意义。 相似文献
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Mark A. Kaemingk Brian D. S. Graeb Christopher W. Hoagstrom David W. Willis 《河流研究与利用》2007,23(7):786-791
There is an expansive and expanding delta at the confluence of the Niobrara and Missouri Rivers in the Lewis and Clark Reservoir. The delta provides diverse aquatic habitat that is somewhat similar to the historic Missouri River and to remnant river habitats. As such, the delta may have relatively high fish species diversity compared to lentic reservoir habitats. To compare patterns of fish diversity between the delta and reservoir habitats, we collected fish in several nursery habitats in both areas using four gear types (seine, gill net, electrofisher and fyke net) on three occasions (July, August and September) in 2005. Species richness was higher in the delta ( n = 34) than the reservoir ( n = 22). Thirteen species composed more than 1% of delta collections while only four species composed more than 1% of reservoir collections. Species diversity (Fisher's α) was also significantly higher in the delta. Higher species diversity in the delta may be explained by higher habitat diversity. These results suggest that newly forming deltas have the potential to protect and restore fish species diversity, because they retain natural river functions such as sediment transport and habitat formation. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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W.J. Radigan A.K. Carlson J.L. Kientz S.R. Chipps M.J. Fincel B.D.S. Graeb 《河流研究与利用》2018,34(3):279-287
Geology and hydrology are drivers of water chemistry and thus important considerations for fish otolith chemistry research. However, other factors such as species and habitat identity may have predictive ability, enabling selection of appropriate elemental signatures prior to costly, perhaps unnecessary water/age‐0 fish sampling. The goal of this study was to develop a predictive methodology for using species and habitat identity to design efficient otolith chemistry studies. Duplicate water samples and age‐0 fish were collected from 61 sites in 4 Missouri River reservoirs for walleye Sander vitreus and one impoundment (Lake Sharpe, South Dakota) for other fishes (bluegill Lepomis macrochirus, black crappie Pomoxis nigromaculatus, gizzard shad Dorosoma cepedianum, largemouth bass Micropterus salmoides, smallmouth bass M. dolomieu, white bass Morone chrysops, white crappie P. annularis, and yellow perch Perca flavescens). Water chemistry (barium:calcium [Ba:Ca], strontium:calcium [Sr:Ca]) was temporally stable, spatially variable, and highly correlated with otolith chemistry for all species except yellow perch. Classification accuracies based on bivariate Ba:Ca and Sr:Ca signatures were high (84% across species) yet varied between floodplain and main‐channel habitats in a species‐specific manner. Thus, to maximize the reliability of otolith chemistry, researchers can use species classifications presented herein to inform habitat selection (e.g., study reservoir‐oriented species such as white bass in main‐channel environments) and habitat‐based classifications to inform species selection (e.g., focus floodplain studies on littoral species such as largemouth bass). Overall, species and habitat identity are important considerations for efficient, effective otolith chemistry studies that inform and advance fisheries and aquatic resource management. 相似文献
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A habitat‐based aquatic macroinvertebrate study was initiated in the Lower Missouri River to evaluate relative quality and biological condition of dike pool habitats. Water‐quality and sediment‐quality parameters and macroinvertebrate assemblage structure were measured from depositional substrates at 18 sites. Sediment porewater was analysed for ammonia, sulphide, pH and oxidation–reduction potential. Whole sediments were analysed for particle‐size distribution, organic carbon and contaminants. Field water‐quality parameters were measured at subsurface and at the sediment–water interface. Pool area adjacent and downstream from each dike was estimated from aerial photography. Macroinvertebrate biotic condition scores were determined by integrating the following indicator response metrics: % of Ephemeroptera (mayflies), % of Oligochaeta worms, Shannon Diversity Index and total taxa richness. Regression models were developed for predicting macroinvertebrate scores based on individual water‐quality and sediment‐quality variables and a water/sediment‐quality score that integrated all variables. Macroinvertebrate scores generated significant determination coefficients with dike pool area (R2 = 0.56), oxidation–reduction potential (R2 = 0.81) and water/sediment‐quality score (R2 = 0.71). Dissolved oxygen saturation, oxidation–reduction potential and total ammonia in sediment porewater were most important in explaining variation in macroinvertebrate scores. The best two‐variable regression models included dike pool size + the water/sediment‐quality score (R2 = 0.84) and dike pool size + oxidation–reduction potential (R2 = 0.93). Results indicate that dike pool size and chemistry of sediments and overlying water can be used to evaluate dike pool quality and identify environmental conditions necessary for optimizing diversity and productivity of important aquatic macroinvertebrates. A combination of these variables could be utilized for measuring the success of habitat enhancement activities currently being implemented in this system. Published in 2011 by John Wiley & Sons, Ltd. 相似文献
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1994年6月中旬,珠江流域西、北两江同时发生建国以来最大洪水,波及广西、广东沿江120多个市、县,造成近300亿元惨重的经济损失,直接威胁广州市和珠江三角洲等经济发达的地区。洪灾后反思,痛定思痛,深感对珠江洪水及其危害要有足够的认识,要提高水患意识,总结经验教训,加强防范。 相似文献
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长江是我国最大的河流，长江流域也是我国主要的经济带，因而长江流域的防汛特别是长江干流是头等大事，但长江防汛目前仍面临以下问题：干流及主要支流的防洪标准偏低；重点防洪项目尚末完成，使分洪运用难以达到预期效果；防洪调度和．指挥系统装备落后，给防汛实时调度带来困难；支流尾同地区防洪规划及治理措施尚不尽人意；此外，防洪意识淡薄现象仍还存在，对防汛工作亦有影响。解决上述问题须做到：加强防洪工程建设，加大防汛的投入，尽快完成各支流及尼间地区的防洪规划；加快防汛通讯系统的自动化建设；强化防汛责任制；以法律规范作好防汛工作；加强河道管理，确保河道行洪通畅。 相似文献
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泥沙淤积是形成1998年长江中下游大洪水的重要因素 总被引：2，自引：0，他引：2
从泥沙淤积导致长江干流泄洪能力日益衰退和诱发围垦使通江湖泊调蓄能力逐渐下降出发，论证了泥沙淤积是形成１９９８年长江中下游洪水的重要因素。 相似文献
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N. J. C. Gosch M. L. Miller T. R. Gemeinhardt T. A. Starks A. P. Civiello J. M. Long J. L. Bonneau 《河流研究与利用》2016,32(8):1819-1823
A lack of nutritious food during the first year of life is a hypothesized factor that may limit survival of endangered pallid sturgeon Scaphirhynchus albus in the lower Missouri River (LMOR). Unfortunately, information for age‐0 pallid sturgeon diets remains limited, but diet analyses for age‐0 Scaphirhynchus spp. (sturgeon hereafter) have occurred. Little information, however, exists on age‐0 sturgeon diets in the LMOR; thus, our primary objective was to document age‐0 sturgeon diets in this system. We examined guts contents from 30 individuals, which were genetically identified as shovelnose sturgeon Scaphirhynchus platorynchus, and three stomachs were empty. The remaining age‐0 shovelnose sturgeon consumed chironomid larvae almost exclusively (>98% of prey items consumed). Our results were similar to studies conducted in other systems, and it appears unlikely that a lack of nutritious food was a major factor affecting the individuals captured during this study. This effort provides important information to help guide ongoing adaptive management efforts in the LMOR. © 2016 The Authors. River Research and Applications published by John Wiley & Sons Ltd. 相似文献