Top PDF Effects of Hydroelectric Dam Operation on Downstream Fish Populations

Effects of Hydroelectric Dam Operation on Downstream Fish Populations

Effects of Hydroelectric Dam Operation on Downstream Fish Populations

In contrast, river regulation and hydropeaking regime did have a significant impact on the weight-length relationship of longnose dace and slimy sculpin, while river regulation alone had a significant impact on the weight-length relationship of trout perch. Specifically, river regulation altered the allometric nature of the weight-length relationship, increasing the value of the exponent, b, relative to the naturally flowing river for all three species, while unrestricted hydropeaking increased b relative to restricted hydropeaking for longnose dace and slimy sculpin. The differences in the weight-length relationships between rivers and hydropeaking regimes may be related to a difference in both the abundance and accessibility of food resources between rivers. Condition indices can be correlated with different prey items for fish of different lengths, as a result of ontogenetic diet shifts (Liao et al. 1995). And, although invertebrate abundance was higher in the regulated river (Jones 2013), and hydropeaking can increase invertebrate drift (Lauters et al. 1996; Lagarrigue et al. 2002; Patterson & Smokorowski 2011), food resources may not be equally available to all fish size classes. Jones (2013) found that the nearshore varial zone in the Magpie River generally had lower invertebrate abundance relative to areas in the permanently wetted zone, while in the Batchawana River, invertebrate densities tended to be highest in the nearshore zone. Small (YOY) longnose dace and slimy sculpin are most frequently caught along the river margins (B. Kelly, unpublished data), where invertebrate density is highest in the Batchawana River, while longnose dace migrate to the variable zone in the Magpie River during hydropeaking events, where invertebrate abundance is lower (Bond & Jones 2015). Thus, the difference in the weight-length relationships between rivers and between hydropeaking regimes is likely reflective of the changing accessibility of food resources during the hydropeaking cycle on a daily basis, and on a more long-term basis as fish grow.
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Environmental, ecological and recreational impacts of a proposed hydroelectric dam on the Teno River, Chile

Environmental, ecological and recreational impacts of a proposed hydroelectric dam on the Teno River, Chile

the natural stream dynamics of the Teno River. The average temperature of the Teno River of 12.8°C is able to sustain multiple organisms vital to the ecological integrity of the river. The natural thermal fluctuations of the Teno are symbolic in the support of benthic and fish assemblage characteristics of the area, including abundant yields of rainbow trout. These organisms are fundamental blocks within the trophic levels and support avian communities and other biodiversity while regulating populations and supporting the river continuum. The presence of the dam and controlled outflow will change the magnitude and frequency of the streamflow and will completely eliminate the recurrence of vital flooding events necessary to nourish the adjacent floodplains and recharge underground water supplies. The sediment load characteristic of high mountain streams such as the Teno River rely on a diverse load of sediment sizes ranging from fine grain materials, medium or gravel-like and coarse particles, including labile organic matter from vegetation, for the formation of periphyton stocks and suitable in-stream habitats. The controlled outflow will produce a caudal with contrasting levels of organic matter, available oxygen and minerals. The sediment particles necessary for channel formative processes of weathering and aggradation will be absent and only a few fine particles might successfully be released downstream. The stratified thermocline within the reservoir will release flows with fluctuating temperatures, making it difficult for resilient organisms to adapt to a drastically changing thermal profile.
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What are the consequences of fish entrainment and impingement associated with hydroelectric dams on fish productivity? A systematic review protocol

What are the consequences of fish entrainment and impingement associated with hydroelectric dams on fish productivity? A systematic review protocol

Worldwide over 58,000 dams (>15 m height) have been constructed for various uses including irrigation, flood control, navigation, and hydroelectric power genera- tion [1]. As the number of dams continues to increase worldwide, so too has concerns for their effects on fish populations. Dams can act as a barrier to migratory (i.e., anadromous, catadromous, potamodromous) and resi- dent fish (i.e., those that complete their life cycle within a reservoir or section of the river), fragmenting rivers and degrading habitats. The negative impacts of dams on upstream migration of diadromous fish are widely acknowledged, and the installation of various types of fishways to facilitate upstream passage are commonplace [2]. However, downstream migration of fish at dams remains a challenge [3, 4]. Depending upon the natural history of a given migratory fish, mature adults seek- ing spawning grounds (e.g., catadromous species) or juveniles or post-spawn adults (for iteroparous species) seeking rearing and feeding habitats (e.g., anadromous species) may all need to move downstream past dams. Resident species may also move considerable distances throughout a riverine system for reproduction, rearing, and foraging (e.g., Kokanee salmon Oncorhynchus nerka; white sucker Catostomus commersonii; walleye Sander vitreus) or simply move throughout reservoirs where they may traverse forebay areas.
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The Political Ecology of the Bakun Hydroelectric Dam

The Political Ecology of the Bakun Hydroelectric Dam

154 geography. The topography of the Bakun area is extremely steep and mountainous. As a result, the inundation by the reservoir does not form a ‘classical’ round lake, but a relatively narrow and extremely long one. The customary land for the longhouse nearest to the jetty is but a five-minute boat ride away, but the customary land for the longhouse furthest away takes a whole day. Over the course of fieldwork for this project, the boat trip required 400L of fuel to and fro to get to the location of the displaced longhouse furthest away. For hunters from the latter, this means the need to get bigger boats, more hunting dogs, more powerful outboard motors, and bigger and better insulators to keep the game and fish from spoiling, and spend more time out. This requires significant outlay which few could afford. It denies reasonable access to community resources, is a form of marginalisation and causes the loss of livelihoods of these hunters and fishermen, with a knock-on effect of food insecurity to the wider community. Hunters and fishermen eventually reacted by working in the areas closer to the dam, in the customary lands of other longhouses, despite the historical taboos and the conflicts that these could lead to. The effects on the biota are significant. A camera trap survey of medium to large mammals done for the project (Chapter 6) shows that bearded pig and mousedeer activities and abundances are unusual in the sites close to the jetty while normal activity and abundances recover with upstream distance. Islands also provide a level of isolation or entrapment for species, and on one of two islands surveyed, bearded pigs, the most popular game, were absent. Fisheries have also started declining. The formation of the considerably still lake created islands of fast-flowing water, where streams and waterfalls meet the lake and concentrated but easy-to- deplete populations of fish. According to local fishermen, the sizes of the staple catfish species have greatly decreased in the popular fishing areas near the jetty. One fisherman poisoned a whole tributary just to prevent others from profiting from his longhouse’s stream. A small number of people have tried to start aquaculture but, like hunting, only those who can afford the starting capital can embark on this endeavour, and this turns fish from a public to a private resource.
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H2Oh! The Effects of Hydroelectric Power Production on the Environment in the Western US

H2Oh! The Effects of Hydroelectric Power Production on the Environment in the Western US

Landscape destruction comes in many different forms- flooded reservoirs, river diversions, riverbank erosion, “dead zones” surrounding reservoirs due to drawdown, and far-reaching effects such as changes to ecosystems downstream of hydro plants, marked departure from past flows, long term reduction in summer and peak flows (which can cause wetlands to dry up), reduction of animal populations, reduced spawning success of fish, and 50-55% decrease in shorelines (Rosenberg and Usher, 1995). There could also be a reduction of soil fertility, and some scientists believe that big reservoirs can cause earthquakes as the weight of water pressing on rock weakens the earth’s crust (Spilsbury and Spilsbury, 2008). This is known as reservoir induced seismicity.
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Bedload Sediment Concentration of Sungai Kahang Downstream Kahang Dam in Johor

Bedload Sediment Concentration of Sungai Kahang Downstream Kahang Dam in Johor

from one location to the other within the study area.It can also be observed from the results that immediately after the external works stopped in May, the sediment concentration starts reducing this shows that the higher concentration was not transported naturally by the river flow. But, the higher sediment measured was enhanced by the activities happening at that period.Similar studies by Kehui et al.[14] on Yangtze River reveals that the numerous amount of dams on the river have resulted in a severe change in sediment discharge while little impact is observed on water discharge. The authors also reported that the annual sediment discharge of Yangtze River after impoundment is estimated to have reduced by 60% because most of the sediments are trapped in the reservoir.The study on Yangtze River confirms that introduction of dam on natural rivers will tremendously decline the sediment meant to be naturally transported downstream the river channel.
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Effects of Human Factor on the Fish Fauna in a Drinking-water Resource (Ömerli Dam Lake-IStanbul, Turkey)

Effects of Human Factor on the Fish Fauna in a Drinking-water Resource (Ömerli Dam Lake-IStanbul, Turkey)

ISKI. It was established after a high dam wall was built on Riva Stream in 1972 by DSI to provide drinking water for the city. The Riva Stream was then located between the reservoir and Black Sea as a discharge water system for the reservoir. There are four main streams which are feeding the reservoir at present, namely; the Ozan, the Göçbeyli, the Ball2ca and the Kömürlük. The fifth stream named Paþaköy which was feeding the reservoir until 2004 has been connected to the Riva Stream via a tunnel (3 m diameter and 6 km length) by ISKI in order to prevent domestic and industrial wastewater inputs into the reservoir (Figure 1). Due to input of domestic and industrial wastewater, coming mainly via small streams, the whole water system is mesotrophic . [7]
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Effects on Mortality of Biochemical and Limnological Properties on Some Fish Species in Sultansuyu Dam Lake (Malatya), Turkey

Effects on Mortality of Biochemical and Limnological Properties on Some Fish Species in Sultansuyu Dam Lake (Malatya), Turkey

In this study, hematological and biochemical investigations were carried out on Cyprinus carpio, Leuciscus cephalus, Capoeta trutta ve Capoeta capoeta umbla fish species living in Sultansuyu Dam Lake (Malatya). The physical, chemical and microbiological features of the reservoir were specified and heavy metal analyses were also conducted. As a result of hematological investigation, a statistical increase of P<0.05 in total leukocyte count, and a decrease of P<0.05 in erytrocyte, hemoglobin and hematocrit values were observed. With respect to microbiological analysis, the presence of Enterococcus shows the drainage of domestic wastes into the reservoir. With water analyses, it was found out that the water quality was second rate and the sulphur content in the water was above standard levels. The existence of large amount of sulphur was presumed to be the result of apricot processing. Significant heavy metal pollution was not observed.
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Vibrio diseases of marine fish populations

Vibrio diseases of marine fish populations

HELGOL~NDER MEERESUNTERSUCHUNGEN Helgolander Meeresunters. cause disease in marine fish populations, both wild and cultured. However, increase in the intensity of mariculture, [r]

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Forced Resettlement in Ghana: The Dam and the Affected People: The Bui Hydroelectric Power Project in Ghana

Forced Resettlement in Ghana: The Dam and the Affected People: The Bui Hydroelectric Power Project in Ghana

Table two above was drafted based on the laws above to guide resettlement officials in the compensation process. However, evidence from the field in relation to the above issue of land infertility suggests otherwise. A respondent from Gyama New Settlement said: “If we have been paid the cash compensation for our crops which were destroyed we could even use that to buy insecticides and fertilizers for our farms, but look it’s over two years now and we have not been paid”. Another farmer commented: “With the nature of the land even if you go in for loan to help you farm you will run at a loss and your lenders will come after you”. An elder of Gyama Host Community on the issue of land, eminent domain and compensation said: “Obtaining an area to be resettled has been very easy for the displaced now in Gyama New Settlement because they just approached us that in view of the dam construction and the destruction of their homes they would like to be resettled with us. They chose the area they want but could not specify the actual size of land they would need. After discussing this we came to an agreement to give them the land, so we gave out the land free of charge and there was no time limits attached as well. Therefore, there is no condition whatsoever attached to the land by way of payment, size, and distribution. They therefore acquired the land just by asking. I understand the government has acquired vast portions of land in this area including here but until now the lands have not been surveyed for us to know how much of our land has been acquired so that in the future we can get the due compensation. What I was told broadly is that it’s being worked on but how it is being done we don’t know and frankly we have been telling BPA officials that we are just living in the dark”. Section four of the RPF resettlement entitlement matrix in appendix two explains how compensation will be paid to stools 7 , “equivalent land provided in the new area, land titles
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THE FISH FAUNA OF THE SEYHAN DAM LAKE (ADANA)

THE FISH FAUNA OF THE SEYHAN DAM LAKE (ADANA)

Consequently, very few reports have been given on the fish fauna of the Seyhan Dam Lake. In our study a total of 12 new fish species and 1 genus of 4 families, one species (O. mykiss) be- longing to Salmonidae, 8 species and 1 genus C. carassius, C. gibelio, Acanthobrama sp., Albur- nus sp., S. kottelati, L. pectoralis, C. angorae, C. erhani, belonging to Cyprinidae, one species (C. evreni) belonging to Cobitidae, two species (A. fasciatus and A. mento belonging to Cyprinodon- tidae were first time described from the Seyhan Dam Lake.

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Monitoring Of Dousti Dam During Construction And Operation

Monitoring Of Dousti Dam During Construction And Operation

Try to To control the safety and behaviour of Dousti dam during construction the operation utilizes the information that was installed during instrumentation. Monitoring meant to evaluate the performance of a structure during construction and the operation phase that accommodated with the predictions of the designed time. It requires having the right information at all times, construction which requires collection of information and instrumentation readership to process them. Also the accuracy of the instrument should be checked to ensure information accuracy. With monitoring results and research of innovation process in the instrumentation data, can be possible phenomena being eroded, undermining the dam appearance and to provide the ability to prevent or reduce damages.
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Water quality and sedimentation implications of installing a hydroelectric dam on the Río Baker in Chilean Patagonia

Water quality and sedimentation implications of installing a hydroelectric dam on the Río Baker in Chilean Patagonia

Modeling temperature, dissolved oxygen, and eutrophication in the future reservoir behind Baker 1 allows for the study of fundamental water quality indicators in th[r]

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Hydroelectric Dams: Transboundary Environmental Effects and International Law

Hydroelectric Dams: Transboundary Environmental Effects and International Law

245. See generally UN Convention, supra note 176, arts. 11-19, 30, 33, annex arts. 1-14; Berlin Rules, supra note 138, arts. 56-73; Helsinki Rules, supra note 177, arts. XXVI- XXXVII. UN Convention Part III, entitled Planned Measures, sets forth a framework for avoiding and handling disputes between watercourse States. See UN Convention, supra note 176, arts. 11-18, 33. Article 12, requiring notice, provides that before implementing “planned measures which may have a significant adverse effect upon other watercourse States,” the State is required to give those States “timely notification.” Id. art. 12. This no- tification should include technical data and results from environmental impact statements. Id. This information should be given “in order to enable the notified States to evaluate the possible effects of the planned measures.” Id. The UN Convention Article 13 then specifies a time period for reply to notification, obligations of the notifying state during the reply pe- riod, information regarding the reply to the notification, and information regarding an ab- sence of reply to notification. Id. art. 13. Article 17 addresses consultations and negotia- tions, further showing the importance of State cooperation. See id. art. 17.
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Hazards identification for safety and risk evaluation of hydroelectric dam power generation plant / Ali Mohammad Saedi

Hazards identification for safety and risk evaluation of hydroelectric dam power generation plant / Ali Mohammad Saedi

digunakan untuk mengenal pasti bahaya (hazard) dan menilai risiko di loji janakuasa. hiro-elektrik yang serupa dan juga membenarkan loji penjanakuasa hidro-elektriuk yang[r]

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Evidence of melanoma in wild marine fish populations

Evidence of melanoma in wild marine fish populations

Prevalence and occurrence of novel diseases are reported to be increasing in many organisms worldwide. Understanding the etiology of these diseases, the host organisms they affect and potential causes and consequences are a vital first step in the development of control and management strategies. Many diseases are caused by microbial pathogens, and fish diseases in particular have been shown to be caused by a diversity of such pathogens including bacteria, parasitic copepods, viruses and fungi [1,2,3]. Historically, diseases in fish have been recorded more commonly in species of commercial value, usually farmed fish. This may be due to the higher than normal stocking densities which in turn can lead to higher levels of infections and/or the ease of sampling large numbers and continuous monitoring capabilities. Furthermore, there is also significant economic benefit to identifying pathogens of these commercially reared fish with the aim of ultimately curing them. In aquaculture systems, diseases cause a significant economic loss, with bacteria, viruses and fungi being the dominant pathogens involved [1,3]. In contrast, diseases of wild fish have received considerably less attention and their economic impact on commercial and recreational fisheries is unknown. In addition to microbial diseases common in fish, other diseases such as carcinomas have been extensively studied in the laboratory using fish model systems, including the Xiphophorus (swordtail) [4,5] and, more recently, the Danio (zebrafish) models [5,6]. To date, however, there are no reports of cancers occurring in wild fish
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Downstream Competition and the Effects of Buyer Power

Downstream Competition and the Effects of Buyer Power

Before proceeding to analyze this model, we pause to discuss the justifications for two assumptions in this model. First, we have assumed that the amount of buyer power (γ) is independent of the market concentration in the downstream market (as measured by n). Here we have in mind a situation where the buyer power of a large retailer comes from being in a large number of markets rather than being large in a particular market. This is motivated, in part, by the observation that the colossal scale of retailers such as Wal-Mart is driven more by the fact that it operates in a large number of geographic markets worldwide than from having a large market share in any particular local market. 8 We suppose that an increase in the retailer’s buyer power is brought about by its expansion into an additional geographic market either through de novo entry or through the acquisition of an existing retailer.
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Reservoir Rim Slope Stability Due To Rainfall And Operation Of Susu Dam

Reservoir Rim Slope Stability Due To Rainfall And Operation Of Susu Dam

Abstract: Susu Dam, in Cameron Highlands, is one of the dams in Malaysia with major fluctuation during operation. Leryar Village, which is a settlement of about 400 aborigines, is located on the bank and a rim slope failure could be catastrophic to the community. As such, this study investigates the landslide hazards due to the fluctuation of the reservoir and intense rainfall by conducting soil investigation, hazard mapping and advanced laboratory tests. Tests were conducted to obtain the hydraulic and mechanical properties of the soil, in the saturated and unsaturated states, which are necessary to simulate rapid drawdown and rainfall-induced shallow slides. Results of the slope stability analyses using this method differ greatly from the methods normally used by practitioners. Conventional methods would conclude that the slopes are sufficiently stable with Factor of Safety (FOS) values of at least 1.47, while this method, which involves rigorous testing and numerical modeling, resulted in an FOS of as low as 0.37. This implies the need to conduct extensive soil tests and apply the latest theories in soil mechanics to obtain reliable FOS for shallow failures involving transient flow conditions, such as rapid drawdown and rainfall infiltration. Aerial hazard map, using a qualitative approach, also agrees well with the FOS of the specific slopes. This suggests that a qualitative method of estimating landslide hazard could be used as a precursor to the advanced laboratory testing and slope stability analysis, which is costly and time consuming.
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Downstream processing effects on microbial viability

Downstream processing effects on microbial viability

Intermittent solids ejection is achieved by the inclusion of a number of peripheral ports which are closed with valves. These are controlled either by a timer or by a device that senses the cake depth. The solids ejecting type is used where there is a medium concentration of solids, such as 2-6% so that neither continuous discharge nor batch operation would be optimum. It is also useful for solids which break down or deaggregate under the shear forces of nozzle discharge. Depending on the length to time the rotor remains open either total discharge (of the entire bowl contents) or partial discharge (solids only) may be obtained. Applications of this device include the concentration of cell suspensions, clarification of various juices and food extracts as well as the purification of marine fuels.
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Hydraulic operation of the outlet works for the Lom Pangar dam in Cameroon

Hydraulic operation of the outlet works for the Lom Pangar dam in Cameroon

This paper shows that the outlet works is able to contain the water evacuated by the spillway and regulate the speed to acceptable standards thus avoiding downstream erosion. The Numerical modelling was carried out using the HEC-RAS software of the US Army Corps of Engineers (USACE) and verifies the restitution capacity of the three flow- regulation sluices equipped with gates. The restitution takes place through the loss of energy as the water flows from the spillway through the sluices, the gates, the hydraulic bucket and finally into the river downstream.
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