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1.
大渡河下游典型鱼类的游泳能力测试   总被引:1,自引:0,他引:1       下载免费PDF全文
通过测试鱼类的游泳能力,可为过鱼设施设计和鱼类行为学研究提供基础资料。在水温18.9~24.3℃和5.58~8.17 mg/L溶氧条件下,采用丹麦Loligo System公司的鱼类游泳能力环形试验水槽,以大渡河下游6种典型鱼类胭脂鱼(Myxocyprinus asiaticus)、长薄鳅(Leptobotia elongata)、长鳍吻鮈(Rhinogobio ventralis)、异鳔鳅鮀(Xenophysogobio boulengeri)、唇?(Hemibarbus labeo)、四川白甲鱼(Onychostoma angustistomata)为研究对象,分别对测试其感应流速、临界游泳速度和爆发游泳速度。结果显示:(1)测试鱼的平均感应流速:白甲鱼9.9~12.3 cm/s,唇?8.5~11.1 cm/s,异鳔鳅鮀12.0~17.5 cm/s,胭脂鱼8.3~13.5 cm/s,长薄鳅14.7~18.1 cm/s,长鳍吻鮈14.0~18.6 cm/s;(2)平均临界游速:白甲鱼106.3~131.1 cm/s,唇?67.9~78.4cm/s,异鳔鳅鮀72.9~80.5 cm/s,胭脂鱼78.1~89.9 cm/s,长薄鳅89.6~109.9 cm/s,长鳍吻鮈83.1~103.8 cm/s;(3)平均爆发游速:白甲鱼149.4~159.1 cm/s,唇?98.9~128.5 cm/s,异鳔鳅鮀98.5~141.5 cm/s,胭脂鱼92.3~125.7 cm/s,长薄鳅125.4~151.8 cm/s,长鳍吻鮈128.6~163.8 cm/s。根据测试结果,建议过鱼孔口近底边区域流速为1.0~1.2 m/s,其余高流速区适当放大至1.4~1.5 m/s;鱼道进口流速值为0.7~1.5 m/s,出鱼口设置在流速持续不小于0.3 m/s的水域,过鱼设施平均流速范围为0.6~1.0 m/s。  相似文献
2.
鲢鳙幼鱼临界游泳速度的比较研究   总被引:1,自引:0,他引:1       下载免费PDF全文
通过比较不同鱼类的游泳能力,为鱼道建设和鱼类行为学研究提供基础资料。在(20±1)℃水温下,使用丹麦Loligo System公司的鱼类行为视频跟踪系统,采用Brett流速递增法,以鲢(Hypophthalmichthys molitrix)和鳙(Aristichthys nobilis)为研究对象,体长作为划分依据,分别测定不同体长组鲢鳙临界游泳速度。结果表明:(1)鲢鳙绝对临界游泳速度随着体长的增加而增大,相对临界游泳速度随着体长的增大而减小,鲢体长与绝对临界游泳速度拟合方程为:Y1=0.10X21-0.11X1+55.86(R2=0.85),与相对临界游泳速度拟合方程为:y1=0.02x21-0.87x1+12.86(R2=0.94),鳙体长与绝对临界游泳速度拟合方程为:Y2=0.03X32-1.29X22+21.04X2-29.21(R2=0.85),与相对临界游泳速度拟合方程为:y2=0.02x22-0.87x2+14.81(R2=0.98);(2)相近体长组鲢(10.11±0.24)cm和鳙(10.78±1.34)cm临界游泳速度分别为(65.50±2.08)cm/s和(80.89±4.03)cm/s,可知鳙>鲢,且差异性显著(P<0.05);(16.90±0.55)cm鲢和(15.39±0.62)cm鳙的临界游泳速度为(83.92±3.03)cm/s和(91.62±3.54)cm/s,无显著性差异(P>0.05);(3)通过比较鲢鳙临界游泳速度与突进游泳速度能力,发现鲢的突进游泳速度大于鳙,而临界游泳速度小于后者,可知鲢鳙有氧运动和无氧运动能力之间存在权衡作用,临界游泳速度与突进游泳速度不一定呈现正相关关系。鱼类能否顺利完成上溯需求取决于鱼道内水力条件和自身游泳能力。  相似文献
3.
Abstract  An 8-m long experimental fishway was trialled at three different slopes [8.3% (1:12), 14.3% (1:7) and 20% (1:5)] to examine the potential of the single-plane Denil fishway for the passage of small- and large-bodied native fishes in Australia. Fish between 45 and 630 mm ascended the fishway. The lowest slope enabled the full size range of bony herring Nematalosa erebi (Günther), from 45 to 350 mm fork length, to ascend the fishway successfully as well as a higher numerical proportion; 88% at the 8.3% slope compared with 31% at the 20% slope (fish numbers per trial = 33–3936). These results dispel the notion that Denil fishways are inherently poor for small fishes. Manipulating the design parameters of slope, length, width and possibly depth-over-breadth ratio enables Denil fishways to pass a wide size range of fish, which may greatly extend their present application and enable them to make a greater contribution to the rehabilitation of diverse fish communities.  相似文献
4.
论述了鱼类洄游通道恢复的理论基础,我国鱼类洄游通道恢复的历史和现状,并分析了长江流域鱼类洄游通道阻隔现状及其对鱼类资源的影响。在此基础上提出了长江流域鱼类洄游通道恢复的对策:制定鱼类洄游通道恢复规划;建立鱼类洄游通道恢复的相关法律体系和协调机制;开展鱼类洄游通道恢复关键技术研究;加强鱼类洄游通道恢复研究能力建设,建立科学的技术支撑体系。  相似文献
5.
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.  相似文献
6.
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.  相似文献
7.
To examine the role of longitudinal connectivity on the spatial and temporal dynamics of mountain whitefish (Prosopium williamsoni), we quantified movement and population dynamics following installation of the Landsburg Dam fishway, Cedar River, WA, USA. Mountain whitefish is widely distributed, poorly studied and not the focus of restoration. Before the fishway, mountain whitefish were not observed above the dam. Here, we focus on snorkel counts collected at reach and mesohabitat (e.g. pools) scales over 11 summers on the 20‐km above‐dam segment following restoration. A camera within the ladder provided number, size and movement timing, thereby informing on behaviour and recolonisation. Segment‐scale abundance increased following fish passage reaching an asymptote in 7 years, and mountain whitefish were detected throughout the main stem in 10 years. Annual movement through the ladder increased over time and was positively correlated with instream abundance and discharge, but negatively correlated with water temperature. About 60% of fish movements occurred in spring and early summer, potentially for foraging opportunities. Reach‐scale abundance peaked between 7 and 10 km from the dam; deep, cool (~10.6 to 11.6°C) conditions characterised these reaches. At the mesohabitat scale, mountain whitefish detection increased with depth and velocity after accounting for distance from the dam. Our results show how restoring longitudinal connectivity allowed this nontarget species to colonise newly available habitat. Their response supports the critical roles of longitudinal connectivity and environmental conditions, that manifest at different spatial scales, in dictating how freshwater fish respond to habitat disturbance.  相似文献
8.
River infrastructure such as weirs and hydropower stations commonly present migrating fish with multiple potential passage routes. Knowledge of the cues fish use to navigate such environments is required to protect migrants from hazardous areas and guide them towards safe passage; however, this is currently lacking for many species. Employing high‐resolution positioning telemetry, this study examined movements of downstream migrating adult European eel, Anguilla anguilla, as they encountered a complex of water control structures in one location on the River Stour, southern England. The distribution of eels across five potential routes of passage differed from that predicted based on proportion of discharge alone. Certain routes were consistently avoided, even when the majority of flow passed through them. Passage distribution was partially explained by avoidance in the vicinity of a floating debris boom. Movement paths were nonrandomly distributed across the forebay and eels moved predominantly within a zone 2–4 m from the channel walls. Understanding of avoidance and structure oriented movementation exhibited by eels will help advance effective guidance and downstream passage solutions for adults.  相似文献
9.
Passage of fish through hydropower dams is associated with mortality, delay, increased energy expenditure and migratory failure for migrating fish and the need for remedial measures for both upstream and downstream migration is widely recognised. A functional fish passage must ensure safe and timely passage routes that a substantial portion of migrating fish will use. Passage solutions must address not only the number or percentage of fish that successfully pass a barrier, but also the time it takes to pass. Here, we used radiotelemetry to study the functionality of a fish bypass for downstream‐migrating wild‐caught and hatchery‐released Atlantic salmon smolts. We used time‐to‐event analysis to model the influence of fish characteristics and environmental variables on the rates of a series of events associated with dam passage. Among the modelled events were approach rate to the bypass entry zone, retention rates in both the forebay and the entry zone and passage rates. Despite repeated attempts, only 65% of the tagged fish present in the forebay passed the dam. Fish passed via the bypass (33%), via spill (18%) and via turbines (15%). Discharge was positively related to approach, passage and retention rates. We did not detect any differences between wild and hatchery fish. Even though individual fish visited the forebay and the entry zone on multiple occasions, most fish passed during the first exposures to these zones. This study underscores the importance of timeliness to passage success and the usefulness of time‐to‐event analysis for understanding factors governing passage performance.  相似文献
10.
Knowledge on the extent and mechanisms of fish damage caused by hydropower facilities is important for their ecological improvement. Herein, a novel field‐based fish injury assessment protocol is proposed that includes vitality and four general health criteria, as well as nine lethal and sub‐lethal injury types across 18 body parts. The protocol was validated using 3,087 specimens from four species of hatchery‐reared fish, as well as 2,262 specimens from 32 species of wild fish. The protocol allowed a detailed and systematic evaluation of different fish injury types in the field. Injuries related to handling and to contact with different parts of the hydropower structure could be distinguished applying multivariate statistics. This approach allows quantification and comparison of fish injuries across sites, and can help to identify the technologies and operational procedures that minimise damage to fish. It may also be useful to assess fish health in other contexts including aquaculture.  相似文献
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