306 research outputs found
Strategic upgrading and firm resources: a study on Zhejiang's textile and clothing industry
This article describes a study of PIT-tagged lamprey (Petromyzon marinus) ascending 4 fishways comprising 3 designs at two dams on the Connecticut River, USA. Migration between dams was rapid (median migration rate = 23 km d-1). Movement through the fishways was much slower, however (median = 0.02 - 0.33 km d-1). Overall delay at dams was substantial (median =13.6 - 14.6 d); many fish failed to pass (percent passage: 29% - 55%), and repeated passage attempts compounded delay for both passers and failers. Cox regression revealed that fishway entry rates were influenced by flow, temperature, and diel cycle, with most lampreys entering at night and at elevated flows, but with no apparent effect of sex or length. Overall delay was influenced by slow movement through the fishway, but repeated failures were the primary factor determining delay. These data suggest that although some lamprey were able to pass fishways they did so with difficulty, and delays incurred as they attempted to pass may act to limit their range.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
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Merging biology and technology to achieve selective bi-directional fish passage
Selective, bi-directional fish passage can ease tensions between connectivity actions fish managers take to improve production of native and desirable fishes. Dam removal and fish passage can enhance fish production by increasing connectivity between tributaries and lakes or oceans. Conversely, in-stream barriers to movement can benefit native fishes by limiting the spread and reproduction of invasive species. To address the tensions, the Great Lakes Fishery Commission is leading a team of nearly 60 fisheries biologists, managers, and engineers in developing novel and effective tools to selectively pass desirable fishes while simultaneously blocking and removing invasive species. A uniquely designed facility (FishPass) is being planned for construction at the Boardman River’s Union Street Dam (Traverse City, MI) to stimulate research that integrates a suite of fish sorting, guidance, and passage technologies and techniques for selective bi-directional fish passage at conditions consistent with the scale and conditions of natural rivers. To be successful, selective fish passage solutions will require the integration and redundancy of automated technologies that both exploit and overcome sortable attributes of fish (i.e., phenology, behavior, physiology, and morphology). This presentation will discuss the status of the FishPass including conceptual designs, research agenda, and next steps
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Session B9: Influence of Biometric Parameters, Flow Condition and Water Temperature on Iberian Fish Sprinting Behavior: Volitionally Swimming Performance
Abstract:
Knowing the swimming ability of fish is important to detect movement limitations through hydraulic structures: fish passes weirs and slots, gauging stations, culverts, bridges foundations and other. All these obstacles are collectively referred to velocity barriers . Fish behavior will determine the passage of these structures through combination of fish swimming performance and motivation. Once the fish decides to enter the barrier, must swim faster than the speed of the flow to advance. Thus, the swimming performance depends on the fish speed and fatigue time. To estimate these values, we experimented in an open channel flow with fish samples of different size, swimming volitionally against several high-velocity flows and water temperature range. The movement of fish was controlled by PIT telemetry systems and video record. The information obtained (fish speed, ascend time and distance traveled) was processed using survival analysis techniques and the results can be applied to practical problem solving velocity barriers.
We have worked with two species of Iberian fish: Iberian barbel (Luciobarbus bocagei) and Northern straight-mouth nase (Pseudochondrostoma duriense). The biometrics parameters, flow velocity and water temperature have a significant influence in fish behavior. Endurance and swimming ability of these species do not differ greatly between them and is much higher than the values which are obtained using other methods as respirometers. The results challenge established fish passage guidelines, suggesting that in some cases these species are capable of passing much higher velocities than was previously believed
A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin
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Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies
This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and strike velocities, and an absence of structures that can lead to grinding or abrasion injuries. Additional information is needed to rigorously assess the nature and magnitude of effects on individuals and populations, and to refine criteria for design of more fish-friendly hydrokinetic turbines. Evaluation of Fish Injury and Mortality Associated with Hydrokinetic Turbines Flume studies exposed fish to two hydrokinetic turbine designs to determine injury and survival rates and to assess behavioral responses. Also, a theoretical model developed for predicting strike probability and mortality of fish passing through conventional hydro turbines was adapted for use with hydrokinetic turbines and applied to the two designs evaluated during flume studies. The flume tests were conducted with the Lucid spherical turbine (LST), a Darrieus-type (cross flow) turbine, and the Welka UPG, an axial flow propeller turbine. Survival rates for rainbow trout tested with the LST were greater than 98% for both size groups and approach velocities evaluated. Turbine passage survival rates for rainbow trout and largemouth bass tested with the Welka UPG were greater than 99% for both size groups and velocities evaluated. Injury rates of turbine-exposed fish were low with both turbines and generally comparable to control fish. Video observations of the LST demonstrated active avoidance of turbine passage by a large proportion fish despite being released about 25 cm upstream of the turbine blade sweep. Video observations from behavior trials indicated few if any fish pass through the turbines when released farther upstream. The theoretical predictions for the LST indicated that strike mortality would begin to occur at an ambient current velocity of about 1.7 m/s for fish with lengths greater than the thickness of the leading edge of the blades. As current velocities increase above 1.7 m/s, survival was predicted to decrease for fish passing through the LST, but generally remained high (greater than 90%) for fish less than 200 mm in length. Strike mortality was not predicted to occur during passage through a Welka UPG turbine at ambient current velocities less than about 2.5 m/s. Survival and Behavior of Juvenile Atlantic Salmon and Adult American Shad on Exposure to a Hydrokinetic Turbine This report describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon and upstream migrating adult American shad. Studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control. No injuries were observed, and there was no measurable increase in mortality associated with turbine passage. Exposure to the turbine elicited behavioral responses from both species, however, with salmon passing primarily over the downrunning blades. Shad movement was impeded in the presence of the device, as indicated by fewer attempts of shorter duration and reduced distance of ascent up the flume. More work should be performed in both laboratory and field conditions to determine the extent to which observed effects are likely to influence fish in riverine environments. Analysis is needed to assess the potential for multiple units to lead to greater mortality rates or impacts on fish movements and migrations. Additionally, future research should focus on expanding the existing data by developing better estimates of encounter and avoidance probabilities
Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies
This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and strike velocities, and an absence of structures that can lead to grinding or abrasion injuries. Additional information is needed to rigorously assess the nature and magnitude of effects on individuals and populations, and to refine criteria for design of more fish-friendly hydrokinetic turbines. Evaluation of Fish Injury and Mortality Associated with Hydrokinetic Turbines Flume studies exposed fish to two hydrokinetic turbine designs to determine injury and survival rates and to assess behavioral responses. Also, a theoretical model developed for predicting strike probability and mortality of fish passing through conventional hydro turbines was adapted for use with hydrokinetic turbines and applied to the two designs evaluated during flume studies. The flume tests were conducted with the Lucid spherical turbine (LST), a Darrieus-type (cross flow) turbine, and the Welka UPG, an axial flow propeller turbine. Survival rates for rainbow trout tested with the LST were greater than 98% for both size groups and approach velocities evaluated. Turbine passage survival rates for rainbow trout and largemouth bass tested with the Welka UPG were greater than 99% for both size groups and velocities evaluated. Injury rates of turbine-exposed fish were low with both turbines and generally comparable to control fish. Video observations of the LST demonstrated active avoidance of turbine passage by a large proportion fish despite being released about 25 cm upstream of the turbine blade sweep. Video observations from behavior trials indicated few if any fish pass through the turbines when released farther upstream. The theoretical predictions for the LST indicated that strike mortality would begin to occur at an ambient current velocity of about 1.7 m/s for fish with lengths greater than the thickness of the leading edge of the blades. As current velocities increase above 1.7 m/s, survival was predicted to decrease for fish passing through the LST, but generally remained high (greater than 90%) for fish less than 200 mm in length. Strike mortality was not predicted to occur during passage through a Welka UPG turbine at ambient current velocities less than about 2.5 m/s. Survival and Behavior of Juvenile Atlantic Salmon and Adult American Shad on Exposure to a Hydrokinetic Turbine This report describes a series of experiments designed to measure the effect of exposure to a full-scale, vertical axis hydrokinetic turbine on downstream migrating juvenile Atlantic salmon and upstream migrating adult American shad. Studies were performed in a large-scale, open-channel flume, and all individuals approached the turbine under volitional control. No injuries were observed, and there was no measurable increase in mortality associated with turbine passage. Exposure to the turbine elicited behavioral responses from both species, however, with salmon passing primarily over the downrunning blades. Shad movement was impeded in the presence of the device, as indicated by fewer attempts of shorter duration and reduced distance of ascent up the flume. More work should be performed in both laboratory and field conditions to determine the extent to which observed effects are likely to influence fish in riverine environments. Analysis is needed to assess the potential for multiple units to lead to greater mortality rates or impacts on fish movements and migrations. Additionally, future research should focus on expanding the existing data by developing better estimates of encounter and avoidance probabilities
Feasibility of investment in Blue Growth multiple-use of space and multi-use platform projects; results of a novel assessment approach and case studies
Highlights• A comprehensive history of multiple use of space blue growth.• New metrics for comparing salmon to megawatts are presented.• Method and criteria for ranking potential investments in blue growth business models.• Profitable case studies described involving electricity, water, mussels and fish.Blue Growth is the creation of economic activity and jobs at sea, while multiple use of space makes efficient use of the available sea area by combining industries. Clearly there are many combinations and many value propositions. However, most technologies to date are considered blue sky concepts, with little robust techno-economic analysis demonstrating profitability.AbstractThe paper begins by providing a comprehensive review of Blue Growth and multi-use in Blue Growth; both in policy as well as the wide range of current technologies, including ocean energy, offshore wind energy, offshore aquaculture and desalination.The Maribe H2020 project provides the vehicle for the research element of the paper. The major contribution is a new methodology for selecting, filtering, developing and ranking business propositions for multiple-use of space (MUS) and multi-use platforms (MUP). Application of the method for the first time identified three case studies where Blue Growth combination projects can be economically viable, with attractive internal rate of return (IRRs). Results presented for the case studies report standard investment metrics and show the relative contribution of each product (energy, food, water) to the system profitability, as well as socio-economic impact. Existing companies were fully engaged in the process. Co-creation between sector experts and industry led to both improved business value propositions and robust assessment of investment readiness. In contrast to the presumption that large scale platforms are commercially attractive, the highest ranking case study companies required smaller capital expenditure (CAPEX) and operated in niche subsectors.In conclusion, the positive economic performance of the case studies should provide confidence for the EC as well as investors that MUS and MUP have viable economic futures leading towards commercialisation. The macro and micro assessment methods will be particularly useful in other Blue Economy contexts and in other multiple product contexts
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