一种鱼道进口诱鱼结构装置的试验研究

常规鱼道的研究和设计大多侧重于其内部结构和水流条件等方面,对鱼道进口位置布置及结构优化的研究相对较少,往往存在鱼类发现并进入鱼道较为困难的情况。通过建立鱼道进口设计的生态水力学指标,提出了某项目集诱鱼进口所需要满足的流速范围为0.47～1.30 m/s,将鱼类游泳能力与鱼道进口流态指标相结合,用标准三维κ-ε模型数值模拟的方式,对以往鱼道进口位置的选择原则进行了验证,提出了一种可控流量、流速的新型诱鱼补水装置,对鱼道进口结构进行优化。该诱鱼补水装置利用局部水流落差,上游发电下泄水流进行诱鱼补水,避免采用自库区压力管道引水而产生的消能问题,降低了鱼道运行的成本;同时降低机组满发或发电流量较高时河段内的流速,可达到灵活调控诱鱼水流进而诱导鱼类进入鱼道完成洄游的效果,最终完成鱼道进口的优化,提高过鱼效果。     

亚马逊流域玛代拉河Santo Antonio 鱼道设计与建设的启示

Santo Antonio过鱼设施位于亚马逊河最大支流玛代拉河下游，其设计规模宏大，在世界范围内鲜有，并且工程建设地所在区域水文环境和鱼类生物学特征等与我国长江较为类似，通过分析该过鱼设施，得出启示主要包括：（1）过鱼设施是为生物对象设计的水利工程，其设计和建设过程中必须由工程师和生物学家紧密合作；（2）吸引水流对过鱼设施的成败起关键性作用，虽然吸引水流系统需要加大投资并且运行过程中会损失大量的水能，但从确保过鱼设施效果而言是非常必要的；（3）物理模型对于鱼道进口位置，鱼道内部水力学特征的确定等具有重要参考价值，尤其在1:1局部模型内开展的生物学实验是细化和优化鱼道内部结构细节的有效方法；（4）卵石框(石笼）隔板的水池分隔方法兼具水池式鱼道与仿自然通道的双重特征，并且完工后还可以根据鱼道的运行情况灵活调整，非常方便；（5）进口处采用较高的人字闸门，即可适应尾水变化，又可与吸引水流系统相配合，创造出有效的吸引水流，一举多得；（6）全部采用大功率灯泡式水轮机是保护下行鱼类的有效措施；（7）监测系统和公众教育等配套设施的建设非常必要，有利于改进鱼道运行方式和提高过鱼效率。     

不同电学参数和流速下的拦鱼电栅对草鱼幼鱼的拦导效率

为了探究不同电学参数的拦鱼电栅在静水条件下对草鱼幼鱼[体长(10.22±2.01) cm、体质量(34.25±3.62) g]趋避行为的影响,实验构建了一种双排式的拦鱼电栅,在静水条件下采用3因素4水平正交实验设计,测试了脉冲电压、脉冲频率、脉冲宽度等脉冲直流电参数对拦鱼效果的影响;为了探究静水下拦鱼效果最佳的拦鱼电栅电学参数在不同流速下的适应性,在鱼道模型中设置了3种流速条件(0.15、0.25和0.35 m/s)分别进行放鱼实验,测试了不同流速下拦鱼电栅对鱼道进口诱鱼效率的影响。结果显示,(1)在静水条件下,工况7阻拦率最高(88.67±1.10)%、平均昏迷率较低,对拦鱼效果的影响由大到小的因素分别为脉冲电压、脉冲频率、脉冲宽度;(2)通过方差分析和单因素多重比较,得到了在静水条件下对草鱼幼鱼的拦鱼效果最佳的拦鱼电栅电学参数,即脉冲电压设置为160 V/m、脉冲频率为6 Hz、脉冲宽度为16 ms;(3)采用静水条件下的最佳电学参数设置(脉冲电压为160 V/m、脉冲频率为6 Hz、脉冲宽度为16 ms),当河道流速为0.15 m/s时,拦鱼电栅的开启能够显著提高草鱼幼鱼的鱼道进...     

应用于鱼道设计的新疆木扎提河斑重唇鱼的游泳能力测试

为了探究斑重唇鱼的游泳能力，给过鱼设施设计和鱼类游泳行为学研究提供基础参数，本研究以木扎提河野生斑重唇鱼(全长TL=12~16 cm)为研究对象，测定了其在(16.6±1.6) ℃水温下的感应流速、临界游泳速度、爆发游泳速度及持续与耐久游泳能力。结果显示，斑重唇鱼感应流速为(0.18±0.02)m/s，相对感应流速为(1.40±0.23) BL/s (BL为体长)；临界游泳速度为(1.02±0.15) m/s，相对临界游泳速度为(8.58±1.65) BL/s；爆发游泳速度为(1.39±0.17) m/s，相对爆发游泳速度为(10.92±1.86) BL/s；最大持续游泳速度为0.87 m/s，最大耐久游泳速度为1.37 m/s，与平均爆发游泳速度相近。其持续游泳时间与流速呈负相关(${\rm lg}T = - 5.136{{X}} + 8.504$)。当以斑重唇鱼为主要过鱼对象时，建议为吸引鱼类进入鱼道，进口流速设计为1.02~1.39 m/s，休息池主流设计为0.20~1.02 m/s，鱼道竖缝处流速宜低于0.85 m/s。鱼道长度为1 000 m时，鱼道内平均水流速度应低于0.78 m/s。本研究结果可为新疆木扎提河流域鱼类游泳能力研究提供参考，对保护日益减少的鱼类资源具有重要意义。     

鱼道进口布置方案研究

鱼道进口的布置除受其自身布置原则的限制之外，还受到枢纽布置及河势、地形、地质、下游水位等其他边界条件的限制。为同时满足以上双重要求，对某工程鱼道进口的布置进行深入研究，提出一种能满足边界条件及绝大部分布置原则的初步布置方案。对该初步布置方案中不能满足布置原则的采取相应的工程措施加以优化。水工模型验证表明，优化后的鱼道进口布置方案对河道中的洄游鱼类具有较大的吸引能力，在流量、流态、水深及流速等方面，均能较好地满足设计要求。     

鳙幼鱼下行过坝的水力导鱼栅实验

分析不同叶片角和布置角下导鱼栅的导鱼效果,获取最优的导鱼栅布置方式,为下行过鱼设施设计提供理论依据及参考。以鳙(Aristichthys nobilis)幼鱼为研究对象,通过设置导鱼栅布置角度(15°、30°、45°)和叶片角度(15°、30°、45°、90°),在室内开展模型实验,分析鳙从导鱼旁路下行(引导成功)和从导鱼栅叶片间隙下行(引导失败)的通过率,确定最优运行工况。结果表明:在所有工况下,实验鱼均出现了顶流现象,但顶流率均小于50%;导鱼栅布置角和叶片角同为30°时,辅助鱼类下行的成功率最高,达95%;其他工况下,成功率均低于75%。导鱼栅附近的水力条件表明,流速沿着导鱼栅方向呈现波浪线上升,紊动能分布总体呈现先上升后下降的趋势,紊动能范围为0~0.0032 m²/s²。     

新疆某枢纽工程鱼道的设计

新疆某枢纽工程为低水头拦河建筑物，位于河流平原区，两岸地形平坦开阔。１１月－翌年３月，泄洪闸全部开启，河道基本为自然状态，鱼类可以自由通过；４－１０月，部分泄洪闸关闭，是本工程的过鱼季节。过鱼对象主要是新疆裸重唇鱼等需要短距离迁徙的裂鳆鱼类，兼顾草鱼、鲢等经济鱼类。综合考虑诱鱼能力、过鱼能力、鱼类适应程度、建造成本和运行维护等因素，其过鱼设施经过比选后选定为仿自然通道型鱼道。介绍了该工程仿自然通道型鱼道的论证与设计过程，为低水头拦河建筑物的过鱼设施设计提供借鉴。     

基于鱼类游泳能力的鱼道设计流速解析

短须裂腹鱼（Schizothorax wangchiachii）是黑水河流域生态修复重要的保护鱼类，为了使过鱼设施取得最佳过鱼效果，鱼类有更好的上溯路径，需要针对性探究过鱼对象的游泳能力指标；基于鱼道的水力学特性，对短须裂腹鱼感应流速、临界游泳速度、爆发游泳速度以及游泳耐力进行研究。结果表明，短须裂腹鱼的感应流速为（0.09±0.03）m/s，相对感应流速为（0.39±0.15）BL/s，流速0.04~0.14 m/s，趋流率（F）随流速（V）增大而显著增大，F=0.7576lnV+2.485（R2=0.97，P＜0.01）；临界游泳速度（Ucrit）为（1.41±0.18）m/s，相对临界游泳速度（U’crit）为（6.27±1.14）BL/s；递增流速法测得的爆发游泳速度(Uburst)为（1.83±0.23）m/s，相对爆发游泳速度(U’burst)为（7.95±1.04）BL/s；固定流速法测得爆发游泳速度为1.8 m/s，持续游泳速度为1.2 m/s，在1.2~1.8 m/s耐久游速区间，持续游泳时间（T）随游泳速度（V）增大而减小，lgT = -4.5015V+9.468 (R2=0.69，P＜0.01)。结合鱼道水力学特性，推荐鱼道最小流速为0.20 m/s，高速区流速小于1.44 m/s，鱼道进口部分流速为1.20~1.44 m/s，休息池段流速为0.20~1.16 m/s。     

高坝鱼道工程设计案例分析

坝高１１６ｍ，最大水头６７.０ｍ，额定水头５３．５ｍ。主要过鱼季节为３－６月，兼顾过鱼季节为２月、７－１０月。综合考虑工程特性和过鱼对象生态习性，设计采用竖缝式池室结构型式鱼道，主要由进口段、槽身段、暗涵段、明渠段、过坝段、出口段、进口补水设施和观测研究室等部分组成，全长３５６６．３２５ｍ。共设置２个常用进口，２个备用进口，鱼道过鱼孔设计流速１．１ｍ／ｓ。介绍了鱼道设计技术路线及研究方法，提出了休息池、鱼道进口、补水设施和带集鱼池的观测研究室的设计思路。     

萨拉康水电站鱼道设计方案探讨

介绍了湄公河渔业资源概况及其流域下游主要的洄游鱼类，分析了萨拉康水电站阻隔对洄游鱼类造成的影响，确定了上游湄公河洄游系统的主要过鱼对象；根据萨拉康水电站枢纽布置以及所在地的地形地质特征，对可行的鱼道布置方案进行了优选论证，并对右岸方案鱼道进口、鱼道出口、鱼道结构、附属设施等进行了初步设计探讨。     

障碍物对鲢幼鱼游泳动力学的影响

为了解鱼在复杂水流环境中的运动行为,提升鱼道过鱼效果,实验通过在水槽中放置障碍物,分析不同来流速度(1,3和5 BL/s)(BL/s即体长每秒)下鲢幼鱼顶流静止和顶流前进时的游泳动力学表现,提取的游泳动力学指标有摆尾频率、摆尾幅度、对地游泳速度、游泳加速度和运动步长。结果发现,半流速度1 BL/s下,与自由来流相比,鲢幼鱼在障碍物后方顶流静止时,摆尾频率降低,摆尾幅度增加;顶流前进时,摆尾频率、对地游泳速度、游泳加速度和运动步长降低,摆尾幅度增加。半流速度3 BL/s下,障碍物有助于节省鱼类运动能量的消耗。在有障碍物的水流中,顶流静止时的摆尾频率随流速的增加而增加;顶流前进时,摆尾频率、摆尾幅度和游泳加速度随流速增大而增大,而运动步长随流速增大而减小。位置偏好研究表明,当流速为3 BL/s时,鲢幼鱼明显集中在距离障碍物后方约5～30 cm处游动,停留时间占比达92.5%,可能采用了卡门步态的运动模式;当流速为1和5 BL/s时,鲢幼鱼没有表现出非常明显的位置偏好;在自由来流中,鲢常贴壁游泳,亦没有明显的位置偏好,表明障碍物和流速的结合可为鱼类提供水流藏匿场,研究结果为鱼道设计提供重要参考依据。     

Atlantic salmon, Salmo salar L., and sea trout, Salmo trutta L., passage in a regulated northern river – fishway efficiency, fish entrance and environmental factors

The number and the size of Atlantic salmon, Salmo salar L., using the Isohaara fishway was elevated by increasing the fishway discharge and by changing the type of the pass entrance. The fishway is intended to help fish bypass a hydroelectric station located close to the mouth of the large, regulated River Kemijoki, in northern Finland. Multi-sea-winter (MSW) salmon returned to the river mouth during peak flows in early June but did not use the fishway until 1 month later. Their number in the fishway was positively correlated with the tailwater level. One-sea winter (1-SW) salmon, which arrived approximately one month later, started to enter the fishway without corresponding delays. In autumn, a high tailwater level and a small drop at the fish entrance seemed to be needed for the successful passage of these small-sized salmon and sea trout, Salmo trutta L.     

A quantitative assessment of fish passage efficiency

In an attempt to restore the connectivity of fragmented river habitats, a variety of passage facilities have been installed at river barriers. Despite the cost of building these structures, there has been no quantitative evaluation of their overall success at restoring fish passage. We reviewed articles from 1960 to 2011, extracted data from 65 papers on fish passage efficiency, size and species of fish, and fishway characteristics to determine the best predictors of fishway efficiency. Because data were scarce for fishes other than salmonids (order Salmoniformes), we combined data for all non‐salmonids for our analysis. On average, downstream passage efficiency was 68.5%, slightly higher than upstream passage efficiency of 41.7%, and neither differed across the geographical regions of study. Salmonids were more successful than non‐salmonids in passing upstream (61.7 vs. 21.1%) and downstream (74.6 vs. 39.6%) through fish passage facilities. Passage efficiency differed significantly between types of fishways; pool and weir, pool and slot and natural fishways had the highest efficiencies, whereas Denil and fish locks/elevators had the lowest. Upstream passage efficiency decreased significantly with fishway slope, but increased with fishway length, and water velocity. An information‐theoretic analysis indicated that the best predictors of fish passage efficiency were order of fish (i.e. salmonids > non‐salmonids), type of fishway and length of fishway. Overall, the low efficiency of passage facilities indicated that most need to be improved to sufficiently mitigate habitat fragmentation for the complete fish community across a range of environmental conditions.     

Fishway with two entrance branches: Understanding its performance for potamodromous Mediterranean barbels

Many fish passes have been built across the world in recent years. This study analyses the performance of a modified type of pool and weir fishway with two access branches, using passive integrated transponder telemetry. A circum‐Mediterranean barbel, Luciobarbus bocagei (Steindachner, 1864), was chosen as the target species. Both hydraulic values (flow and volumetric energy dissipation) and biological parameters (attraction, entrance and passage success) were measured in the fishway, these being related to the environmental variables affecting upstream fish movement. Flow discharge, water temperature and atmospheric pressure were important for fish entering the fishway. There was no preference between path routes, even though the main discharge was concentrated in the turbine channel. This type of fishway design could be an alternative for the conservation of fish populations where multiple fish approach options are possible.     

竖缝式鱼道桩柱结构过鱼效果探索

竖缝式鱼道作为一种协助鱼类洄游上溯从而缓解提升河流连通性 的设施得到广泛的应用,但是多数鱼道的实际过鱼效能并不理想,尤其 是鱼道的池室结构尚具有一定的提升空间。本研究通过数值模拟和对照性过鱼试验对池室内部未增加和4种方式增加桩柱的池室水流结构进行了比较分析。结果表明在鱼道主流中间增设桩柱结构,可以有效减小回流区面积,减幅达49%;并减小竖缝处紊动能,最大紊动能减小18%;增加鱼类上溯路线分布,提高了池室空间利用率更高 。分析两种结构的上溯轨迹发现,齐口裂腹鱼多选择回流区外侧上溯,避免进入回流区中心,多选择较高的水力应变与紊动能区域调整作为上溯方向 ,且上溯路线中偏好较低水力因子区域上溯,上溯偏好流速范围0.01~0.09m/s,紊动能范围0.001~0.008m2/s2,水力应变范围0.2~3.0s-1     

Denil fishway utilization patterns and passage of several warmwater species relative to seasonal, thermal and hydraulic dynamics

Abstract – Two different Denil fishways on the Grand River, Ontario, were used as check-points to evaluate the upstream movement of fishes past a low-head weir and to examine the proportions and inferred swimming performance of non-salmonid warmwater fishes that used each fishway type. Traps installed at fishway exits were used to collect fish during 24-hour sampling periods, over 40–51 days each year, from 1995 to 1997. Passage rates, size selectivity, water temperature, water velocity and turbidity for the periods of maximum passage for each year were examined. General species composition from trap samples shifted from catostomids to cyprinids to ictalurids to percids and centrarchids, with some overlap, as water temperatures increased from 8 °C to 25 °C in the spring and early summer. Water depths, and therefore water velocities in each fishway, were independent of river discharge due to variable accumulations of debris on upstream trash-racks. Relationships between the water velocity and the swimming and position-holding abilities of several species emerged. Turbidity was directly related to river discharge and precipitation events, and many species demonstrated maximum fishway use during periods of increased turbidity. This study 1) provided evidence of strongly directional upstream movements among several species that were previously considered non-migratory and 2) describes physical and hydraulic conditions during fishway use for 29 non-salmonid fish species.     

The future of fish passage science,engineering, and practice

Much effort has been devoted to developing, constructing and refining fish passage facilities to enable target species to pass barriers on fluvial systems, and yet, fishway science, engineering and practice remain imperfect. In this review, 17 experts from different fish passage research fields (i.e., biology, ecology, physiology, ecohydraulics, engineering) and from different continents (i.e., North and South America, Europe, Africa, Australia) identified knowledge gaps and provided a roadmap for research priorities and technical developments. Once dominated by an engineering‐focused approach, fishway science today involves a wide range of disciplines from fish behaviour to socioeconomics to complex modelling of passage prioritization options in river networks. River barrier impacts on fish migration and dispersal are currently better understood than historically, but basic ecological knowledge underpinning the need for effective fish passage in many regions of the world, including in biodiversity hotspots (e.g., equatorial Africa, South‐East Asia), remains largely unknown. Designing efficient fishways, with minimal passage delay and post‐passage impacts, requires adaptive management and continued innovation. While the use of fishways in river restoration demands a transition towards fish passage at the community scale, advances in selective fishways are also needed to manage invasive fish colonization. Because of the erroneous view in some literature and communities of practice that fish passage is largely a proven technology, improved international collaboration, information sharing, method standardization and multidisciplinary training are needed. Further development of regional expertise is needed in South America, Asia and Africa where hydropower dams are currently being planned and constructed.     

Use of a vertical-slot fishway by galaxiids in Western Australia

Abstract –  The Goodga River Fishway is the first vertical-slot fishway in Western Australia and was opened in April 2003 with the aim of increasing the habitat available to two galaxiids; the trout minnow ( Galaxias truttaceus ), a highly restricted freshwater fish species in Western Australia, and the widespread common jollytail ( Galaxias maculatus ). The fishway was designed to function during low flows to coincide with the upstream spawning migration of G. truttaceus . Prior to the opening of the fishway, no fish were found above the Goodga River gauging station (weir), which is approximately 2 km upstream of the river's entrance to Moates Lake. Fish migrations were monitored in each season between April 2003 and February 2005. Galaxias truttaceus utilised the fishway in all sampling periods. Adult fish migrated up the fishway prior to spawning, while large numbers of new recruits (small juveniles) negotiated the fishway during November 2003 and 2004. More G. truttaceus and G. maculatus were captured on the fishway during daylight hours compared with the night; however, larger G. truttaceus were more commonly captured at night whereas G. maculatus on the fishway were larger during the day. The fact that fishway utilisation by G. maculatus was consistent during all samples and new recruits migrated during periods of low flow demonstrates the importance of understanding the migration patterns of the target species when designing fishways.     

Fish and lamprey passage in a combined Denil and vertical slot fishway

A fishway (fish pass), consisting of vertical slot and Denil sections, was constructed at the lowest dam on the River Kemijoki, northern Finland, in 1993. The river was one of the best salmon rivers in Europe until 1949, when the dam and the hydropower plant were completed close to the river mouth. From 1993 to 1995, nearly 1000 adult salmonids passed through the fishway despite heavy fishing below the dam. Of environmental variables measured, water temperature, headwater level, and discharge through the power plant in relation to season changes explained most of the variation in Baltic salmon, Salmo salar L., numbers. They had a minor effect on trout, Salmo trutta L. Migratory whitefish, Coregonus lavaretus (L.), entered the fishway but were not observed in its uppermost pool. River lamprey, Lampetra fluviatilis (L.), passed through the vertical slot section of the fishway after plastic bristles were fastened into the bottom of the slots.