The Danish fish fauna during the warm Atlantic period (ca. 7000-3900 bc): Forerunner of future changes?

DEFF Research Database (Denmark)

Enghoff, I.B.; MacKenzie, Brian; Eg Nielsen, Einar

2007-01-01

Vast amounts of fish bone lie preserved in Denmark's soil as remains of prehistoric fishing. Fishing was particularly important during the Atlantic period (ca. 7000-3900 bc, i.e. part of the Mesolithic Stone Age). At this time, sea temperature and salinity were higher in waters around Denmark than...... today. Analyses of more than 100,000 fish bones from various settlements from this period document which fish species were common in coastal Danish waters at this time. This study provides a basis for comparing the fish fauna in the warm Stone Age sea with the tendencies seen and predicted today...... frequently caught species in the Danish Stone Age sea. These results demonstrate that major changes to the fish fauna near Denmark will occur as climate changes. However, exploitable cod populations can potentially be maintained in waters near Denmark, including the North Sea, but the vulnerability...

Drivers and uncertainties of forecasted range shifts for warm-water fishes under climate and land cover change

Science.gov (United States)

Bouska, Kristen; Whitledge, Gregory W.; Lant, Christopher; Schoof, Justin

2018-01-01

Land cover is an important determinant of aquatic habitat and is projected to shift with climate changes, yet climate-driven land cover changes are rarely factored into climate assessments. To quantify impacts and uncertainty of coupled climate and land cover change on warm-water fish species’ distributions, we used an ensemble model approach to project distributions of 14 species. For each species, current range projections were compared to 27 scenario-based projections and aggregated to visualize uncertainty. Multiple regression and model selection techniques were used to identify drivers of range change. Novel, or no-analogue, climates were assessed to evaluate transferability of models. Changes in total probability of occurrence ranged widely across species, from a 63% increase to a 65% decrease. Distributional gains and losses were largely driven by temperature and flow variables and underscore the importance of habitat heterogeneity and connectivity to facilitate adaptation to changing conditions. Finally, novel climate conditions were driven by mean annual maximum temperature, which stresses the importance of understanding the role of temperature on fish physiology and the role of temperature-mitigating management practices.

Predicting the occurrence of cold water patches at intermittent and ephemeral tributary confluences with warm rivers

Science.gov (United States)

Small, cold tributary streams can provide important thermal refuge habitat for cold-water fishes such as Pacific salmon (Oncorhynchus spp.) residing in warm, downstream receiving waters. We investigated the potential function of small perennial and non-perennial tributary stream...

Warming shelf seas drive the subtropicalization of European pelagic fish communities.

Science.gov (United States)

Montero-Serra, Ignasi; Edwards, Martin; Genner, Martin J

2015-01-01

Pelagic fishes are among the most ecologically and economically important fish species in European seas. In principle, these pelagic fishes have potential to demonstrate rapid abundance and distribution shifts in response to climatic variability due to their high adult motility, planktonic larval stages, and low dependence on benthic habitat for food or shelter during their life histories. Here, we provide evidence of substantial climate-driven changes to the structure of pelagic fish communities in European shelf seas. We investigated the patterns of species-level change using catch records from 57,870 fisheries-independent survey trawls from across European continental shelf region between 1965 and 2012. We analysed changes in the distribution and rate of occurrence of the six most common species, and observed a strong subtropicalization of the North Sea and Baltic Sea assemblages. These areas have shifted away from cold-water assemblages typically characterized by Atlantic herring and European sprat from the 1960s to 1980s, to warmer-water assemblages including Atlantic mackerel, Atlantic horse mackerel, European pilchard and European anchovy from the 1990s onwards. We next investigated if warming sea temperatures have forced these changes using temporally comprehensive data from the North Sea region. Our models indicated the primary driver of change in these species has been sea surface temperatures in all cases. Together, these analyses highlight how individual species responses have combined to result in a dramatic subtropicalization of the pelagic fish assemblage of the European continental shelf. © 2014 John Wiley & Sons Ltd.

Fewer bacteria in warm water

International Nuclear Information System (INIS)

Bagh, Lene

1999-01-01

There has been many suggestions to how the ideal warm water system should be. Particularly whether warm water containers or heat exchangers in larger houses are the best solutions in order to maintain a water quality with low levels of bacteria. In an investigation made by Statens Byggeforskningsinstitutt (Denmark) regarding ''Bacterial growth in warm water installations with heat exchangers'' there were used several heat exchangers made by Gjelsted and Lund of three of which had HWAT heating cables. The bacterial content was low from these exchangers compared to exchangers with circulation. The article presents promising results from a study where the method was investigated over a longer period in two new larger warm water systems. Some energy conservation aspects are discussed

Innovative water withdrawal system re-establishes fish migration runs

International Nuclear Information System (INIS)

Anon.

2008-01-01

This article described a unique water withdrawal and fish bypass structure that is under construction in Oregon to re-establish anadromous fish runs and to improve water quality downstream of the Round Butte dam. Portland General Electric and the Confederated Tribes of the Warm Springs Reservation, which co-own the dam, have committed to re-establish fish runs in response to concerns over the declining numbers of salmon and trout in the region. Water intakes are routinely added at hydroelectric facilities to protect native fish in compliance with the Federal Energy Regulatory Commission and the Clean Water Act. The Round Butte Hydroelectric project had a complex set of challenges whereby surface-current directions had to be changed to help migrating salmon swim easily into a fish handling area and create a fish collection system. CH2M HILL designed the system which consists of a large floating structure, an access bridge, a large vertical conduit and a base structure resting on the lake bed. Instead of using 2D CAD file methods, CH2M HILL decided to take advantage of 3D models to visualize the complex geometry of these structures. The 3D models were used to help designers and consultants understand the issues, resolve conflicts and design solutions. The objective is to have the system operating by the 2009 migrating season. 1 ref., 4 figs

The influence of cooling water outlet of the Ringhals power plant on the coastal fish colony

International Nuclear Information System (INIS)

Neuman, E.

1988-03-01

Fish abundance has been monitored with fyke nets in 1976-1987 at the cooling-water outlet from the Ringhals nuclear power plant at the Swedish west coast and in a reference area. Judging from the dependence of the catches on temperature, Myoxocephalus scorpius, Zoarces viviparus, Gadus morhua and Platichtys flesus can be classified as cold-water species and Symphodus melops, Ctenolabrus rupestris, Carci nus maenas and Anguilla anguilla as warm-water species. As a rule the warm-water species were more and the cold-water fishes less abundant in the outlet area than in the reference area. The catch of the economically important Anguilla was about three times greater in the heated area. A lower abundance than expected of Ctenolabrus and Myoxocephalus at the outlet may be caused by a loss of eggs and larvae in the cooling-water system. (author)

An observational study on the temperature rising effects in water warming canal and water warming pond

Energy Technology Data Exchange (ETDEWEB)

Hong, J. B.; Hong, S. B. [Rural Development Cooperation, Seoul (Korea, Republic of)

1990-09-15

The power water flowed out from the multipurpose darn influences the ecosystem approximately because of the low water temperature. An appropriate counter measure to the rising water temperature is needed for growing crops especially when the temperature is below 18°C in the source of the irrigation water This observational study is practiced in Yong-Doo water warming canal and pond in the down stream of Choong-Ju multipurpose dam and is practiced for analyse and compare the rising effects in actural water temperature by actual measurement with the rising effects of planned water temperatuer by the basic theoritical method and for the help to present the direction in plan establishment through investigate the results afterwards. The results are as follows. 1. The degree of the rise of the water temperature can be decided by θ{sub x} = θ{sub 0} + K (L/(v * h)) * (T - θ{sub 0}) Then, K values of a factor representing the characteristics of the water warming canal were 0.00002043 for the type I. and 0.0000173 for the type II. respectively. 2. A variation of water temperature which produced by the difference effective temperature and water temperature in the water warming canal was θ{sub x1} = 16.5 + 15.9 (1-e{sup -0.00018x}), θ{sub x2} = 18.8 + 8.4(1-e{sup -0.000298x}) for the type I. and θ{sub x} = 19.6 + 12.8 (1-e{sup -0.00041x}) for the type II. 3. It was shown that the effects of the rise of water temperature for the type I. water warming canal were greater than that of type II. as a resultes of broadening the surface of the canal compared with the depth of water, coloring the surface of water canal and installing the resistance block. 4. In case of the type I. water warming canal, the equation between the air temperature and the degree of the rise of water temprature could be made; Y = 0.4134X + 7.728 In addition, in case of the type II. water warming canal, the correlation was very low. 5. A monthly variation of the water temperature in the water warming

Water quality and fish dynamics in forested wetlands associated with an oxbow lake

Science.gov (United States)

Andrews, Caroline S.; Miranda, Leandro E.; Kroger, Robert

2015-01-01

Forested wetlands represent some of the most distinct environments in the Lower Mississippi Alluvial Valley. Depending on season, water in forested wetlands can be warm, stagnant, and oxygen-depleted, yet may support high fish diversity. Fish assemblages in forested wetlands are not well studied because of difficulties in sampling heavily structured environments. During the April–July period, we surveyed and compared the water quality and assemblages of small fish in a margin wetland (forested fringe along a lake shore), contiguous wetland (forested wetland adjacent to a lake), and the open water of an oxbow lake. Dissolved-oxygen levels measured hourly 0.5 m below the surface were higher in the open water than in either of the forested wetlands. Despite reduced water quality, fish-species richness and catch rates estimated with light traps were greater in the forested wetlands than in the open water. The forested wetlands supported large numbers of fish and unique fish assemblages that included some rare species, likely because of their structural complexity. Programs developed to refine agricultural practices, preserve riparian zones, and restore lakes should include guidance to protect and reestablish forested wetlands.

Habitat Quality and Anadromous Fish Production on the Warm Springs Reservation. Final Report.

Energy Technology Data Exchange (ETDEWEB)

Fritsch, Mark A.

1995-06-01

The number of anadromous fish returning to the Columbia River and its tributaries has declined sharply in recent years. Changes in their freshwater, estuarine, and ocean environments and harvest have all contributed to declining runs of anadromous fish. Restoration of aquatic resources is of paramount importance to the Confederated Tribes of the Warm Springs (CTWS) Reservation of Oregon. Watersheds on the Warm Springs Reservation provide spawning and rearing habitat for several indigenous species of resident and anadromous fish. These streams are the only ones in the Deschutes River basin that still sustain runs of wild spring chinook salmon, Oncorhynchus, tshawytscha. Historically, reservation streams supplied over 169 km of anadromous fish habitat. Because of changes in flows, there are now only 128 km of habitat that can be used on the reservation. In 1981, the CTWS began a long-range, 3-phase study of existing and potential fish resources on the reservation. The project, consistent with the Northwest Power Planning Council`s Fish and Wildlife Program, was designed to increase the natural production of anadromous salmonids on the reservation.

Habitat quality and anadromous fish production on the Warm Springs Reservation. Final report

International Nuclear Information System (INIS)

Fritsch, M.A.

1995-06-01

The number of anadromous fish returning to the Columbia River and its tributaries has declined sharply in recent years. Changes in their freshwater, estuarine, and ocean environments and harvest have all contributed to declining runs of anadromous fish. Restoration of aquatic resources is of paramount importance to the Confederated Tribes of the Warm Springs (CTWS) Reservation of Oregon. Watersheds on the Warm Springs Reservation provide spawning and rearing habitat for several indigenous species of resident and anadromous fish. These streams are the only ones in the Deschutes River basin that still sustain runs of wild spring chinook salmon, Oncorhynchus, tshawytscha. Historically, reservation streams supplied over 169 km of anadromous fish habitat. Because of changes in flows, there are now only 128 km of habitat that can be used on the reservation. In 1981, the CTWS began a long-range, 3-phase study of existing and potential fish resources on the reservation. The project, consistent with the Northwest Power Planning Council's Fish and Wildlife Program, was designed to increase the natural production of anadromous salmonids on the reservation

Uses of warmed water in agriculture. Final report

International Nuclear Information System (INIS)

Garrett, R.E.

1978-11-01

Energy in the form of warmed water is available from condenser cooling water from fossil fuel or nuclear-electric power-generating facilities, geothermal power plants, geothermal fluids, or spent steam and cooling water from industrial processes. A re-analysis of the characteristics of possible agricultural uses of warmed water has revealed the need to decouple considerations of warmed water sources from those of warmed water users. Conflicting objectives and managerial requirements seem to preclude an integrated system approach. Rather an interface must be established with separate costs and benefits identified for a reliable warmed water source and for its various potential uses. These costs and benefits can be utilized as a basis for decisions separately by the energy supplier and the prospective energy users. A method of classifying uses of warmed water according to need, volume, objective, temperature, and quality is presented and preliminary classifications are discussed for several potential agricultural uses of warmed water. Specific uses for soil warming, space heating in greenhouses, and irrigation are noted. Specific uses in aquaculture for catfish, lobster, and prawn production are discussed. Warmed water use in animal shelters is mentioned. Low-quality heat is required for methane generation from biomass and warmed water heating could be utilized in this industry. 53 references

Preliminary Evidence for the Amplification of Global Warming in Shallow, Intertidal Estuarine Waters.

Directory of Open Access Journals (Sweden)

Autumn Oczkowski

Full Text Available Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the warming recorded in the winter and early spring. A recent survey and synthesis of data from four locations in Southern Rhode Island has led us to hypothesize that this warming may be amplified in the shallow (<1 m, nearshore portions of these estuaries. While intertidal areas are not typically selected as locations for long-term monitoring, we compiled data from published literature, theses, and reports that suggest that enhanced warming may be occurring, perhaps at rates three times higher than deeper estuarine waters. Warmer spring waters may be one of the factors influencing biota residing in intertidal regions both in general as well as at our specific sites. We observed greater abundance of fish, and size of Menidia sp., in recent (2010-2012 seine surveys compared to similar collections in 1962. While any linkages are speculative and data are preliminary, taken together they suggest that shallow intertidal portions of estuaries may be important places to look for the effects of climate change.

Preliminary Evidence for the Amplification of Global Warming in Shallow, Intertidal Estuarine Waters.

Science.gov (United States)

Oczkowski, Autumn; McKinney, Richard; Ayvazian, Suzanne; Hanson, Alana; Wigand, Cathleen; Markham, Erin

2015-01-01

Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the warming recorded in the winter and early spring. A recent survey and synthesis of data from four locations in Southern Rhode Island has led us to hypothesize that this warming may be amplified in the shallow (<1 m), nearshore portions of these estuaries. While intertidal areas are not typically selected as locations for long-term monitoring, we compiled data from published literature, theses, and reports that suggest that enhanced warming may be occurring, perhaps at rates three times higher than deeper estuarine waters. Warmer spring waters may be one of the factors influencing biota residing in intertidal regions both in general as well as at our specific sites. We observed greater abundance of fish, and size of Menidia sp., in recent (2010-2012) seine surveys compared to similar collections in 1962. While any linkages are speculative and data are preliminary, taken together they suggest that shallow intertidal portions of estuaries may be important places to look for the effects of climate change.

Predicting interactions among fishing, ocean warming, and ocean acidification in a marine system with whole-ecosystem models.

Science.gov (United States)

Griffith, Gary P; Fulton, Elizabeth A; Gorton, Rebecca; Richardson, Anthony J

2012-12-01

An important challenge for conservation is a quantitative understanding of how multiple human stressors will interact to mitigate or exacerbate global environmental change at a community or ecosystem level. We explored the interaction effects of fishing, ocean warming, and ocean acidification over time on 60 functional groups of species in the southeastern Australian marine ecosystem. We tracked changes in relative biomass within a coupled dynamic whole-ecosystem modeling framework that included the biophysical system, human effects, socioeconomics, and management evaluation. We estimated the individual, additive, and interactive effects on the ecosystem and for five community groups (top predators, fishes, benthic invertebrates, plankton, and primary producers). We calculated the size and direction of interaction effects with an additive null model and interpreted results as synergistic (amplified stress), additive (no additional stress), or antagonistic (reduced stress). Individually, only ocean acidification had a negative effect on total biomass. Fishing and ocean warming and ocean warming with ocean acidification had an additive effect on biomass. Adding fishing to ocean warming and ocean acidification significantly changed the direction and magnitude of the interaction effect to a synergistic response on biomass. The interaction effect depended on the response level examined (ecosystem vs. community). For communities, the size, direction, and type of interaction effect varied depending on the combination of stressors. Top predator and fish biomass had a synergistic response to the interaction of all three stressors, whereas biomass of benthic invertebrates responded antagonistically. With our approach, we were able to identify the regional effects of fishing on the size and direction of the interacting effects of ocean warming and ocean acidification. ©2012 Society for Conservation Biology.

Water temperature, not fish morph, determines parasite infections of sympatric Icelandic threespine sticklebacks (Gasterosteus aculeatus).

Science.gov (United States)

Karvonen, Anssi; Kristjánsson, Bjarni K; Skúlason, Skúli; Lanki, Maiju; Rellstab, Christian; Jokela, Jukka

2013-06-01

Parasite communities of fishes are known to respond directly to the abiotic environment of the host, for example, to water quality and water temperature. Biotic factors are also important as they affect the exposure profile through heterogeneities in parasite distribution in the environment. Parasites in a particular environment may pose a strong selection on fish. For example, ecological differences in selection by parasites have been hypothesized to facilitate evolutionary differentiation of freshwater fish morphs specializing on different food types. However, as parasites may also respond directly to abiotic environment the parasite risk does not depend only on biotic features of the host environment. It is possible that different morphs experience specific selection gradients by parasites but it is not clear how consistent the selection is when abiotic factors change. We examined parasite pressure in sympatric morphs of threespine stickleback (Gasterosteus aculeatus) across a temperature gradient in two large Icelandic lakes, Myvatn and Thingvallavatn. Habitat-specific temperature gradients in these lakes are opposite. Myvatn lava rock morph lives in a warm environment, while the mud morph lives in the cold. In Thingvallavatn, the lava rock morph lives in a cold environment and the mud morph in a warm habitat. We found more parasites in fish living in higher temperature in both lakes, independent of the fish morph, and this pattern was similar for the two dominating parasite taxa, trematodes and cestodes. However, at the same time, we also found higher parasite abundance in a third morph living in deep cold-water habitat in Thingvallavatn compared to the cold-water lava morph, indicating strong effect of habitat-specific biotic factors. Our results suggest complex interactions between water temperature and biotic factors in determining the parasite community structure, a pattern that may have implications for differentiation of stickleback morphs.

Plasticity in habitat use determines metabolic response of fish to global warming in stratified lakes.

Science.gov (United States)

Busch, Susan; Kirillin, Georgiy; Mehner, Thomas

2012-09-01

We used a coupled lake physics and bioenergetics-based foraging model to evaluate how the plasticity in habitat use modifies the seasonal metabolic response of two sympatric cold-water fishes (vendace and Fontane cisco, Coregonus spp.) under a global warming scenario for the year 2100. In different simulations, the vertically migrating species performed either a plastic strategy (behavioral thermoregulation) by shifting their population depth at night to maintain the temperatures occupied at current in-situ observations, or a fixed strategy (no thermoregulation) by keeping their occupied depths at night but facing modified temperatures. The lake physics model predicted higher temperatures above 20 m and lower temperatures below 20 m in response to warming. Using temperature-zooplankton relationships, the density of zooplankton prey was predicted to increase at the surface, but to decrease in hypolimnetic waters. Simulating the fixed strategy, growth was enhanced only for the deeper-living cisco due to the shift in thermal regime at about 20 m. In contrast, simulating the plastic strategy, individual growth of cisco and young vendace was predicted to increase compared to growth currently observed in the lake. Only growth rates of older vendace are reduced under future global warming scenarios irrespective of the behavioral strategy. However, performing behavioral thermoregulation would drive both species into the same depth layers, and hence will erode vertical microhabitat segregation and intensify inter-specific competition between the coexisting coregonids.

Assessing the Effects of Water Right Purchases on Stream Temperatures and Fish Habitat

Science.gov (United States)

Elmore, L.; Null, S. E.

2012-12-01

Warm stream temperature and low flow conditions are limiting factors for native trout species in Nevada's Walker River. Water rights purchases are being considered to increase instream flow and improve habitat conditions. However, the effect of water rights purchases on stream temperatures and fish habitat have yet to be assessed. Manipulating flow conditions affect stream temperatures by altering water depth, velocity, and thermal mass. This study uses the River Modeling System (RMSv4), an hourly, physically-based hydrodynamic and water quality model, to estimate flows and stream temperatures in the Walker River. The model is developed for two wet years (2010-2011). Study results highlight reaches with cold-water habitat that is suitable for native trout species. Previous research on the Walker River has evaluated instream flow changes with water rights purchases. This study incorporates stream temperatures as a proxy for trout habitat, and thus explicitly incorporates water quality and fish habitat into decision-making regarding water rights purchases. Walker River

Warm Water Entrainment Impacts and Environmental Life Cycle Assessment of a Proposed Ocean Thermal Energy Conversion Pilot Plant Offshore Oahu, Hawaii

Science.gov (United States)

Hauer, Whitney Blanchard

Ocean thermal energy conversion (OTEC) is a marine renewable energy technology that uses the temperature difference of large volumes of cold deep and warm surface seawater in tropical regions to generate electricity. One anticipated environmental impact of OTEC operations is the entrainment and subsequent mortality of ichthyoplankton (fish eggs and larvae) from the withdrawal of cold and warm seawater. The potential ichthyoplankton loss from the warm water intake was estimated for a proposed 10 MW OTEC pilot plant offshore Oahu, HI based on ambient vertical distribution data. The estimated losses due to entrainment from the warm water intake were 8.418E+02 larvae/1000 m3, 3.26E+06 larvae/day, and 1.19E+09 larvae/year. The potential entrained larvae/year is 1.86 X greater than at the Kahe Generating Station (Kapolei, HI), a 582 MW oil-fired power plant. Extrapolating to age-1 equivalence (9.2E+02 and 2.9E+02 yellowfin and skipjack tuna, respectively), the estimated yearly losses from warm water entrainment of yellowfin and skipjack tuna fish eggs and larvae represent 0.25-0.26 % and 0.09-0.11 % of Hawaii's commercial yellowfin and skipjack tuna industry in 2011 and 2012. An environmental life cycle assessment (LCA) was developed for the proposed OTEC plant operating for 20 and 40 years with availability factors of 0.85, 0.95, and 1.0 to determine the global warming potential (GWP) and cumulative energy demand (CED) impacts. For a 20 year operational OTEC plant, the GWP, CED, energy return on investment (EROI), and energy payback time (EPBT) ranged from 0.047 to 0.055 kg CO2eq/kWh, 0.678 to 0.798 MJ/kWh, 4.51 to 5.31 (unitless), and 3.77 to 4.43 years, respectively. For a 40 year operational OTEC plant, the GWP, CED, EROI, and EBPT ranged from 0.036 to 0.043 kg CO2eq/kWh, 0.527 to 0.620 MJ/kWh, 5.81 to 6.83 (unitless), and 5.85 to 6.89 years, respectively. The GWP impacts are within the range of renewable energy technologies and less than conventional electricity

Reproductive acclimation to increased water temperature in a tropical reef fish.

Directory of Open Access Journals (Sweden)

Jennifer M Donelson

Full Text Available Understanding the capacity of organisms to cope with projected global warming through acclimation and adaptation is critical to predicting their likely future persistence. While recent research has shown that developmental acclimation of metabolic attributes to ocean warming is possible, our understanding of the plasticity of key fitness-associated traits, such as reproductive performance, is lacking. We show that while the reproductive ability of a tropical reef fish is highly sensitive to increases in water temperature, reproductive capacity at +1.5°C above present-day was improved to match fish maintained at present-day temperatures when fish complete their development at the higher temperature. However, reproductive acclimation was not observed in fish reared at +3.0°C warmer than present-day, suggesting limitations to the acclimation possible within one generation. Surprisingly, the improvements seen in reproduction were not predicted by the oxygen- and capacity-limited thermal tolerance hypothesis. Specifically, pairs reared at +1.5°C, which showed the greatest capacity for reproductive acclimation, exhibited no acclimation of metabolic attributes. Conversely, pairs reared at +3.0°C, which exhibited acclimation in resting metabolic rate, demonstrated little capacity for reproductive acclimation. Our study suggests that understanding the acclimation capacity of reproductive performance will be critically important to predicting the impacts of climate change on biological systems.

Nutrition, feeding, and behavior of fish.

Science.gov (United States)

Lall, Santosh P; Tibbetts, Sean M

2009-05-01

Nutrition and feeding influence growth, reproduction, and health of fish and their response to physiologic and environmental stressors and pathogens. The basics of fish metabolism are similar to those of warm-blooded animals in that they involve food intake, digestion, absorption, and transport of nutrients to the various tissues. Fish, however, being the most primitive form of vertebrates, possess some distinguishing features which will be discussed. Unlike warm-blooded animals, which are homoeothermic, fish are poikilothermic, so their body temperature and metabolic rate depends on the water temperature and this has practical implications for the nutrition, feeding and health of fish. Several behavioral responses have been linked to methods of feeding, feeding habits, frequency of feeding, mechanisms of food detection, and food preferences. Fish are also unique among vertebrates in their ability to absorb minerals not only from their diets but also from water through their gills and skin.

Methodological issues affecting the study of fish parasites. I. Duration of live fish storage prior to dissection.

Science.gov (United States)

Kvach, Yuriy; Ondračková, Markéta; Janáč, Michal; Jurajda, Pavel

2016-05-03

We tested the ability of parasite species to respond quickly to artificial conditions (e.g. by changing abundance or even decreasing to extinction) while host fish species were being held alive prior to dissection. Prussian carp Carassius gibelio were sampled by electrofishing from 2 ponds alongside the River Dyje (Czech Republic) during 'cold' and 'warm' seasons. All fish were transported to the laboratory in aerated pond water and kept in a 1 m3 outdoor basin with aged tap water for 6 d. Twenty fish were dissected on consecutive days (total 120 fish for each site). Our results indicated that there was little change in parasite loading over the first 3 d of holding, suggesting no impact on parasitological studies undertaken over this period. From the fourth day, however, overall parasite abundance increased due to rapid reproduction of some parasite species, especially gyrodactylids in the cold season and dactylogyrids in the warm season. Parasite diversity appeared less stable in the warm season, with significant differences being registered as early as the second day. In addition to holding period, environmental conditions during fish holding will also play an important role in parasite community shifts.

Electrolytically generated hydrogen warm water cleanses the keratin-plug-clogged hair-pores and promotes the capillary blood-streams, more markedly than normal warm water does

Directory of Open Access Journals (Sweden)

Yoshiharu Tanaka

2018-01-01

Full Text Available Biomedical properties of hydrogen water have been extensively investigated, but the effect of hydrogen on good healthy subjects remains unclear. This study was designed to explore the hygiene improvement by electrolytically generated hydrogen warm water (40°C on capillary blood streams, skin moisture, and keratin plugs in skin pores in normal good healthy subjects with their informed consents. Fingertip-capillary blood stream was estimated after hand-immersing in hydrogen warm water by videography using a CCD-based microscope, and the blood flow levels increased to about 120% versus normal warm water, after 60 minutes of the hand-immersing termination. Skin moisture of subjects was assessed using an electro-conductivity-based skin moisture meter. Immediately after taking a bath filled with hydrogen warm water, the skin moisture increased by 5–10% as compared to before bathing, which was kept on for the 7-day test, but indistinct, because of lower solubility of hydrogen in “warm” water than in room-temperature water. Cleansing of keratin plugs in skin-pores was assessed by stereoscopic microscopy and scanning electron microscopy. After hydrogen warm water bathing, the numbers of cleansed keratin plugs also increased on cheek of subjects 2.30- to 4.47-fold as many as the control for normal warm water. And areas of cleansed keratin plugs in the cheeks increased about 1.3-fold as much as the control. More marked improvements were observed on cheeks than on nostrils. Hydrogen warm water may thoroughly cleanse even keratin-plugs of residual amounts that could not be cleansed by normal warm water, through its permeability into wide-ranged portions of hair-pores, and promote the fingertip blood streams more markedly than merely through warmness due to normal warm water.

Intermediate report on the problems of warm water drainage

International Nuclear Information System (INIS)

1976-01-01

The investigation into the solution of the problems of warm water drainage and its related matters was conducted, and the result was summarized by the warm water drainage sectional committee of the central public nuisance-prevention council entrusted by the Environment Agency. The first section of this report deals with the background of the warm water drainage problems. In December 1970, the environmental pollution prevention act was revised so as to include warm water drainage in the law. The second section deals with the progress of deliberation by the sectional committee. The third section deals with the actual conditions of warm water drainage. The temperature difference at the inlet and outlet of water was 5 to 11 0 C in power plants, 5 to 16 0 C in iron and steel works, 4 to 11 0 C in petroleum refineries, and 7 to 25 0 C in petrochemical plants. The amount of heat energy discharged from power plants was greater than that from the others. Other sections deal with its effects on the living things in water, the forecast of diffusion of warm drainage, the concept of the regulation of warm drainage, and the present countermeasure. Twelve points which require future investigation are listed. They are the change in the phases of living things affected by the change in temperature and flow of warm drainage, the effects on fishery resources, the estimation system for the environmental calorific capacity in the sea, the mechanism of diffusion and the forecasting method for the diffusion range. (Iwakiri, K.)

Evaluating the role of fronts in habitat overlaps between cold and warm water species in the western North Pacific: A proof of concept

Science.gov (United States)

Mugo, Robinson M.; Saitoh, Sei-Ichi; Takahashi, Fumihiro; Nihira, Akira; Kuroyama, Tadaaki

2014-09-01

Cold- and warm-water species' fishing grounds show a spatial synchrony around fronts in the western North Pacific (WNP). However, it is not yet clear whether a front (thermal, salinity or chlorophyll) acts as an absolute barrier to fish migration on either side or its structure allows interaction of species with different physiological requirements. Our objective was to assess potential areas of overlap between cold- and warm-water species using probabilities of presence derived from fishery datasets and remotely sensed environment data in the Kuroshio-Oyashio region in the WNP. Fishery data comprised skipjack tuna (Katsuwonus pelamis) fishing locations and proxy presences (derived from fishing night light images) for neon flying squid (Ommastrephes bartrami) and Pacific saury (Cololabis saira). Monthly (August-November) satellite remotely sensed sea-surface temperature, chlorophyll-a and sea-surface height anomaly images were used as environment data. Maximum entropy (MaxEnt) models were used to determine probabilities of presence (PoP) for each set of fishery and environment data for the area 35-45°N and 140-160°E. Maps of both sets of PoPs were compared and areas of overlap identified using a combined probability map. Results indicated that areas of spatial overlap existed among the species habitats, which gradually widened from September to November. The reasons for these overlaps include the presence of strong thermal/ocean-color gradients between cold Oyashio and warm Kuroshio waters, and also the presence of the sub-arctic front. Due to the high abundance of food along frontal zones, the species use the fronts as foraging grounds while confining within physiologically tolerable waters on either side of the front. The interaction zone around the front points to areas that might be accessible to both species for foraging, which suggests intense prey-predator interaction zones.

Water intake fish diversion apparatus

International Nuclear Information System (INIS)

Taft, E.P. III; Cook, T.C.

1995-01-01

A fish diversion apparatus uses a plane screen to divert fish for variety of types of water intakes in order to protect fish from injury and death. The apparatus permits selection of a relatively small screen angle, for example ten degrees, to minimize fish injury. The apparatus permits selection of a high water velocity, for example ten feet per second, to maximize power generation efficiency. The apparatus is especially suitable retrofit to existing water intakes. The apparatus is modular to allow use plural modules in parallel to adjust for water flow conditions. The apparatus has a floor, two opposite side walls, and a roof which define a water flow passage and a plane screen within the passage. The screen is oriented to divert fish into a fish bypass which carries fish to a safe discharge location. The dimensions of the floor, walls, and roof are selected to define the dimensions of the passage and to permit selection of the screen angle. The floor is bi-level with a level upstream of the screen and a level beneath screen selected to provide a uniform flow distribution through the screen. The apparatus may include separation walls to provide a water flow channel between the apparatus and the water intake. Lead walls may be used to adjust water flow conditions into the apparatus. The apparatus features stoplog guides near its upstream and downstream ends to permit the water flow passage to be dewatered. 3 figs

Water-quality models to assess algal community dynamics, water quality, and fish habitat suitability for two agricultural land-use dominated lakes in Minnesota, 2014

Science.gov (United States)

Smith, Erik A.; Kiesling, Richard L.; Ziegeweid, Jeffrey R.

2017-07-20

Fish habitat can degrade in many lakes due to summer blue-green algal blooms. Predictive models are needed to better manage and mitigate loss of fish habitat due to these changes. The U.S. Geological Survey (USGS), in cooperation with the Minnesota Department of Natural Resources, developed predictive water-quality models for two agricultural land-use dominated lakes in Minnesota—Madison Lake and Pearl Lake, which are part of Minnesota’s sentinel lakes monitoring program—to assess algal community dynamics, water quality, and fish habitat suitability of these two lakes under recent (2014) meteorological conditions. The interaction of basin processes to these two lakes, through the delivery of nutrient loads, were simulated using CE-QUAL-W2, a carbon-based, laterally averaged, two-dimensional water-quality model that predicts distribution of temperature and oxygen from interactions between nutrient cycling, primary production, and trophic dynamics.The CE-QUAL-W2 models successfully predicted water temperature and dissolved oxygen on the basis of the two metrics of mean absolute error and root mean square error. For Madison Lake, the mean absolute error and root mean square error were 0.53 and 0.68 degree Celsius, respectively, for the vertical temperature profile comparisons; for Pearl Lake, the mean absolute error and root mean square error were 0.71 and 0.95 degree Celsius, respectively, for the vertical temperature profile comparisons. Temperature and dissolved oxygen were key metrics for calibration targets. These calibrated lake models also simulated algal community dynamics and water quality. The model simulations presented potential explanations for persistently large total phosphorus concentrations in Madison Lake, key differences in nutrient concentrations between these lakes, and summer blue-green algal bloom persistence.Fish habitat suitability simulations for cool-water and warm-water fish indicated that, in general, both lakes contained a large

FishVis, A regional decision support tool for identifying vulnerabilities of riverine habitat and fishes to climate change in the Great Lakes Region

Science.gov (United States)

Stewart, Jana S.; Covert, S. Alex; Estes, Nick J.; Westenbroek, Stephen M.; Krueger, Damon; Wieferich, Daniel J.; Slattery, Michael T.; Lyons, John D.; McKenna, James E.; Infante, Dana M.; Bruce, Jennifer L.

2016-10-13

Climate change is expected to alter the distributions and community composition of stream fishes in the Great Lakes region in the 21st century, in part as a result of altered hydrological systems (stream temperature, streamflow, and habitat). Resource managers need information and tools to understand where fish species and stream habitats are expected to change under future conditions. Fish sample collections and environmental variables from multiple sources across the United States Great Lakes Basin were integrated and used to develop empirical models to predict fish species occurrence under present-day climate conditions. Random Forests models were used to predict the probability of occurrence of 13 lotic fish species within each stream reach in the study area. Downscaled climate data from general circulation models were integrated with the fish species occurrence models to project fish species occurrence under future climate conditions. The 13 fish species represented three ecological guilds associated with water temperature (cold, cool, and warm), and the species were distributed in streams across the Great Lakes region. Vulnerability (loss of species) and opportunity (gain of species) scores were calculated for all stream reaches by evaluating changes in fish species occurrence from present-day to future climate conditions. The 13 fish species included 4 cold-water species, 5 cool-water species, and 4 warm-water species. Presently, the 4 cold-water species occupy from 15 percent (55,000 kilometers [km]) to 35 percent (130,000 km) of the total stream length (369,215 km) across the study area; the 5 cool-water species, from 9 percent (33,000 km) to 58 percent (215,000 km); and the 4 warm-water species, from 9 percent (33,000 km) to 38 percent (141,000 km).Fish models linked to projections from 13 downscaled climate models projected that in the mid to late 21st century (2046–65 and 2081–2100, respectively) habitats suitable for all 4 cold-water species and 4

CH4 Emission Model from Bos Primigenius Waste in Fish-Water: Implications for Integrated Livestock-Fish Farming Systems

Directory of Open Access Journals (Sweden)

Joshua O. Okeniyi

2013-07-01

Full Text Available This paper studies a methane (CH4 emission model from the waste of cattle (B. primigenius based on trends in integrated livestock-fish farming adoption by farmers in Nigeria. Dung of B. primigenius was employed as substrate in fish-water, obtained from a fish-rearing farm, as a matrix medium for simulating a low-oxygen wastewater environment of an agriculture-aquaculture system. A substrate to fish-water mass ratio of 1:3 was used, developed in a laboratory-size digesting reactor system. Volumetric readings, at ambient temperature conditions and with a retention time of thirty-two days, were then subjected to the logistic probability density function, and tested against correlation coefficient and Nash-Sutcliffe coefficient of efficiency criteria. The readings show that a volume of CH4-containing gas as high as 65.3 x 10−3 dm3 was produced on the 13th day from the B. primigenius substrate. Also, production of 234.59 x 10−3 dm3/kg CH4-containing gas, totaling 703.76 x 10−3 dm3, was observed through the studied retention time. The 60% CH4 constituent model of the measured gas generation showed a potency of 2.0664 kg emission per animal, which is equivalent to 43.3944 CO2eq of global warming potential (GWP annually per animal. This bears environmental and climate change implications, and therefore alternative sustainable practices for integrated livestock-fish farming adoption are suggested.

Assessment of impacts from water level fluctuations on fish in the Hanford Reach, Columbia River

Energy Technology Data Exchange (ETDEWEB)

Becker, C.D.; Fickeisen, D.H.; Montgomery, J.C.

1981-05-01

Observations on the effects of water level fluctuations in the Hanford Reach of the Columbia River, Washington, were made in 1976 and 1977. The two years provided contrasting flow regimes: high water and fluctuations of greater magnitude prevailed in 1976; low water and higher temperatures prevailed in 1977. Situations where fish and other aquatic organisms were destroyed by changing water levels were observed and evaluated each year in three study areas: Hanford, F-Area, and White Bluffs sloughs. Losses primarily were due to stranding, entrapment (with or without complete dewatering), and predation. Juvenile fish were more susceptible to entrapment and stranding than were adult fish. Estimates of actual losses were biased and conservative because relatively few fish could be found after each decline of water level and dewatering. The most valued species of fish affected by water level fluctuations at Hanford were the anadromus fall chinook salmon (Oncorhynchus tshawytscha) and the resident smallmouth bass (Micropterus dolomieui). Crucial periods for chinook salmon occurred during winter when incubating eggs were in the gravel of the main channel, and before and during seaward migration in the spring when fry were abundant in shoreline zones. The crucial period for smallmouth bass was during spring and early summer when adults were spawning in warmed sloughs and shoreline zones. Chinook salmon and smallmouth bass fry were vulnerable to stranding and entrapment, and smallmouth bass nests were susceptible to exposure and temperature changes resulting from repeated water level fluctuations. Thus, flow manipulation may be crucial to their survival. The extent to which other species of riverine fish were affected by water level fluctuations depended upon their use of shoreline zones for spawning and rearing young.

Restoration of Shallow Lakes in Subtropical and Tropical China: Response of Nutrients and Water Clarity to Biomanipulation by Fish Removal and Submerged Plant Transplantation

Directory of Open Access Journals (Sweden)

Jinlei Yu

2016-10-01

Full Text Available Fish removal has been used to restore temperate lakes, and positive effects on ecological state and water clarity have frequently been recorded in many lakes. Recently, a supplementary measure, transplantation of submerged macrophytes after fish removal, has been applied to restore warm Chinese shallow lakes in order to compensate for the expected lack of increasing grazing control of phytoplankton after the biomanipulation. These measures have successfully shifted turbid warm lakes to a clear water state, but little is known about the responses to restoration of key physico-chemical variables. We analyzed the seasonal variation in nutrient concentrations in two subtropical and one tropical biomanipulated shallow Chinese lakes subjected to restoration. In all three lakes, a marked decline occurred in the concentrations of lake total nitrogen (TN, total phosphorus (TP, total suspended solids (TSS, and chlorophyll a (Chl a, while the transparency (SD:WD ratio, Secchi depth to water depth ratio increased. A clear water state was established, lasting so far for 7 to 23 months, and TN, TP, Chl a, and TSS levels in the three restored lakes decreased to, on average, 49%, 58%, 41%, and 18% of the level prior to restoration and/or the level in a reference lake, respectively, while the annual mean SD:WD ratio exhibited a 1.5–4 fold increase. In conclusion, lake restoration by transplantation of submerged macrophytes after fish removal had major positive effects on the physico-chemical variables in our study lakes. However, continuous control of omnivorous and herbivorous fish biomass is recommended as the fish typically present in warm, shallow lakes to some extent feed on submerged macrophytes, when available.

Evaluation of the toxicity and efficacy of hydrogen peroxide treatments on eggs of warm and cool water fishes

Science.gov (United States)

Rach, J.J.; Gaikowski, M.P.; Howe, G.E.; Schreier, Theresa M.

1998-01-01

The use of hydrogen peroxide in aquaculture is growing and there is a need to develop fundamental guidelines to effectively treat diseased fish. The safety (toxicity) of hydrogen peroxide treatments was determined on eggs of representative warm- and coolwater fish species. Eggs of northern pike (Esox lucius), walleye (Stizostedion vitreum), yellow perch (Pel ca flavescens), white sucker (Catostomus commersoni), lake sturgeon (Acipenser fulvescens), paddlefish (Polyodon spathula), common carp (Cyprinus carpio), and channel catfish (Ictalurus punctatus) were cultured in egg jars or aquaria. Treatments were initiated with non-eyed eggs and continued until all viable eggs had hatched. Eggs were treated daily for 15 min Monday through Friday with either 0, 500, 1000, 3000, or 6000 mu l l(-1) of hydrogen peroxide. For all species, the mean percent hatch was greater in eggs treated with 1000 mu l l(-1) hydrogen peroxide for 15 min than in the untreated controls. Common carp, lake sturgeon, and paddlefish were the least sensitive to hydrogen peroxide with percent hatch ranging from 40 to 48% in the 6000 mu l l(-1) hydrogen peroxide treatment. Fungal infections reduced or eliminated the hatch in most controls whereas nearly all treated eggs remained free of infection; hydrogen peroxide inhibited fungal infections on fish eggs. (C) 1998 Elsevier Science B.V. All rights reserved.

Marine ecosystems in alteration under global warming

International Nuclear Information System (INIS)

Prestrud, Paal

2004-01-01

It is commonly thought among fishermen, researchers and in the fishing industries that the administration and harvesting of the fish resources is more important for the stock of fish than are changes in the climate. However, many scientific investigations now link changes in temperature with changes in the spreading, survival and beginning of life processes. There is solid evidence that there are important changes in progress in the North Atlantic marine ecosystem caused by global warming. If the heating of the water masses continues, it will probably have a large impact on the ocean's productivity and consequently for the fishing industry

Comparative studies of metals in fish organs, sediments and water from Nigerian fresh water fish ponds

International Nuclear Information System (INIS)

Ipinmoroti, K.O.; Oshodi, A.A.; Owolabi, R.A.

1997-01-01

Fish samples (Illisha africana) were collected from six man-made fish pond in Edo and Ondo states, Nigeria. Some organs of the fish sediment and water from the fish habitat were analysed for Cd, Pb, Hg, Ca, Fe, Zn, Cu and Cr, Physico-chemical properties of water samples from the ponds were also re-corded. The concentration of the metals varied in the sediment water as well as in different organs of the fish. However, chromium was absent in all the samples. The descending order of metal concentration in fish organs was: gills intestine, head and muscle. To avoid harmful accumulation of these metals in the human system, the gills and the intestine should preferably be discarded while processing fish for consumption. The head with a relatively high concentration of calcium might be useful in feed formulation. (author)

Adapt, move or die - how will tropical coral reef fishes cope with ocean warming?

DEFF Research Database (Denmark)

Habary, Adam; Johansen, Jacob L.; Nay, Tiffany J.

2017-01-01

poleward, away from ocean warming hotspots where temperatures 2-3 °C above long-term annual means can compromise critical physiological processes. We examined the capacity of a model species - a thermally sensitive coral reef fish, Chromis viridis (Pomacentridae) - to use preference behaviour to regulate...

Nanoscale study on water damage for different warm mix asphalt binders

Directory of Open Access Journals (Sweden)

Kefei Liu

2016-11-01

Full Text Available In order to analyze the water damage to different warm mix asphalt binders from the micro scale, five kinds of asphalt binders, 70#A base asphalt, sasobit warm mix asphalt, energy champion 120 °C (EC120 warm mix asphalt, aspha-min warm mix asphalt, sulfur-extended asphalt modifier (SEAM warm mix asphalt, under different conditions (dry/wet, original/aging are prepared for laboratory tests. The atomic force microscope (AFM is used to observe the surface properties and measure the adhesion force between the asphalt and the mineral aggregate. The obtained results show that under the dry condition aspha-min warm mix asphalt and SEAM warm mix asphalt show stronger adhesive ability with the mineral aggregate compared with other asphalt binders, but also have relatively large dispersion and fluctuation in the tested results; under the wet condition, aspha-min warm mix asphalt and SEAM warm mix asphalt show stronger water damage resistance ability. The EC120 warm mix asphalt and aspha-min warm mix asphalt are less sensitive to moist, and their corresponding adhesion force is less susceptible to the change of external moisture conditions, leading to a better ability to resist water erosion. The aging process significantly lowers the moisture erosion resistance ability, which further impairs the water damage resistance ability. The base asphalt is more sensitive to moisture and more vulnerable to water damage, no matter whether it is under original or aging conditions. The aging aspha-min warm mix asphalt has the least loss of adhesion force, the smallest dispersion of the tested adhesion force, the strongest water damage resistance ability, no matter it is dry or wet. Keywords: Road engineering, Warm mix asphalt, Moisture damage, Atomic force microscope, Microcosmic

Change in fish community structure in the Barents Sea.

Directory of Open Access Journals (Sweden)

Michaela Aschan

Full Text Available Change in oceanographic conditions causes structural alterations in marine fish communities, but this effect may go undetected as most monitoring programs until recently mainly have focused on oceanography and commercial species rather than on whole ecosystems. In this paper, the objective is to describe the spatial and temporal changes in the Barents Sea fish community in the period 1992-2004 while taking into consideration the observed abundance and biodiversity patterns for all 82 observed fish species. We found that the spatial structure of the Barents Sea fish community was determined by abiotic factors such as temperature and depth. The observed species clustered into a deep assemblage, a warm water southern assemblage, both associated with Atlantic water, and a cold water north-eastern assemblage associated with mixed water. The latitude of the cold water NE and warm water S assemblages varied from year to year, but no obvious northward migration was observed over time. In the period 1996-1999 we observed a significant reduction in total fish biomass, abundance, mean fish weight, and a change in community structure including an increase in the pelagic/demersal ratio. This change in community structure is probably due to extremely cold conditions in 1996 impacting on a fish community exposed to historically high fishing rates. After 1999 the fish community variables such as biomass, abundance, mean weight, P/D ratio as well as community composition did not return to levels of the early 90s, although fishing pressure and climatic conditions returned to earlier levels.

Evaluation of swimming capability and potential velocity barrier problems for fish. Part A: Swimming performance of selected warm and cold water fish species relative to fish passage and fishway design

International Nuclear Information System (INIS)

Scruton, D. A.; Goosney, R. G.; McKinley, R. S.; Booth, R. K.; Peake, S.

1998-08-01

The objective of this study was to provide information about the swimming capability of several widely distributed, economically or recreationally important fish species, for use in mitigating potential velocity barrier problems associated with hydroelectric power facilities. Swimming capability of anadromous and landlocked Atlantic salmon, brook trout, brown trout, lake sturgeon, and walleye, collected from various locations throughout Canada, were investigated to develop criteria for sustained, prolonged, burst swimming performance characteristics of the study species, fish physiology, life history and migration distance on swimming performance. Swimming performance characteristics in the wild, especially the use of physiological telemetry, as well as development of new methodology for the measurement of burst speed was also central to the study. Models were derived to describe swimming capabilities for each study species/life stage in relation to fish length, water velocity, water temperature, and other significant environmental factors. The data will form the basis of guideline development and decision making to improve design and evaluation of fish passage facilities. A series of annotated bibliographies resulting from the study are described in Appendix B. 74 refs., 8 tabs., figs., 2 appendices

Distribution and accumulation of rotenone in tissues of warm water fishes

International Nuclear Information System (INIS)

Rach, J.J.; Gingerich, W.H.

1986-01-01

The tissue distribution of rotenoid residues was determined in tissues of common carp Cyprinus carpio (88.2 g), bluegills Lepomis macrochirus (47.9 g), and yellow perch Perca flavescens (67.7 g) after the fish were exposed to 50μg/L of rotenone-6a 14 C(15.9 x 10 4 Bq/μM). Exposures were terminated 1 h after the fish were moribund and failed to respond to gentle prodding. The fish were dissected, and various tissues were oxidized to determine 14 C-rotenone accumulation and distribution. Major rotenone metabolites were identified by gradient-elution high performance liquid chromatography. The exposure time required for fish to reach total incapacitation was 3 h for bluegills and yellow perch, and 11.25 h for common carp. The mean rotenoid concentrations (μg/100g fish) in the whole body were 22.4 in yellow perch, 39.7 in bluegills, and 107.8 in common carp. The percentage of rotenone-derived 14 C activity was higher in the carcass components than in the head or viscera; the skin and bone contained about 60% of the carcass activity. The highest relative rotenoid concentrations were found in the liver, bile, gills, brain, and heart. Percentages of total rotenoid material as parent rotenone were highest in yellow perch (70.0 in the viscera and 84.4 in the fillet), followed by those for bluegills (22.7 and 27.8) and common carp (9.7 and 48.5)

Arctic warming will promote Atlantic-Pacific fish interchange

DEFF Research Database (Denmark)

Wisz, Mary; Broennimann, O.; Grønkjær, Peter

2015-01-01

the interchange of marine biota between the two seas. Here, we forecast the potential northward progression of 515 fish species following climate change, and report the rate of potential species interchange between the Atlantic and the Pacific via the Northwest Passage and the Northeast Passage. For this, we...... projected niche-based models under climate change scenarios and simulated the spread of species through the passages when climatic conditions became suitable. Results reveal a complex range of responses during this century, and accelerated interchange after 2050. By 2100 up to 41 species could enter......Throughout much of the Quaternary Period, inhospitable environmental conditions above the Arctic Circle have been a formidable barrier separating most marine organisms in the North Atlantic from those in the North Pacific. Rapid warming has begun to lift this barrier, potentially facilitating...

Monitoring of tritium, 60Co and 137Cs in the vicinity of the warm water outlet of the Paks Nuclear Power Plant, Hungary.

Science.gov (United States)

Janovics, R; Bihari, Á; Papp, L; Dezső, Z; Major, Z; Sárkány, K E; Bujtás, T; Veres, M; Palcsu, L

2014-02-01

Danube water, sediment and various aquatic organisms (snail, mussel, predatory and omnivorous fish) were collected upstream (at a background site) and downstream of the outlet of the warm water channel of Paks Nuclear Power Plant. Gamma emitters, tissue free-water tritium (TFWT) and total organically-bound tritium (T-OBT) measurements were performed. A slight contribution of the power plant to the natural tritium background concentration was measured in water samples from the Danube section downstream of the warm water channel. Sediment samples also contained elevated tritium concentrations, along with a detectable amount of (60)Co. In the case of biota samples, TFWT exhibited only a very slight difference compared to the tritium concentration of the Danube water, however, the OBT was higher than the tritium concentration in the Danube, independent of the origin of the samples. The elevated OBT concentration in the mollusc samples downstream of the warm water channel may be attributed to the excess emission from the nuclear power plant. The whole data set obtained was used for dose rate calculations and will be contributed to the development of the ERICA database. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of Distal Limb Warming With Fluidotherapy and Warm Water Immersion for Mild Hypothermia Rewarming.

Science.gov (United States)

Kumar, Parveen; McDonald, Gerren K; Chitkara, Radhika; Steinman, Alan M; Gardiner, Phillip F; Giesbrecht, Gordon G

2015-09-01

The purpose of the study was to determine the effectiveness of Fluidotherapy rewarming through the distal extremities for mildly hypothermic, vigorously shivering subjects. Fluidotherapy is a dry heat modality in which cellulose particles are suspended by warm air circulation. Seven subjects (2 female) were cooled on 3 occasions in 8˚C water for 60 minutes, or to a core temperature of 35°C. They were then dried and rewarmed in a seated position by 1) shivering only; 2) Fluidotherapy applied to the distal extremities (46 ± 1°C, mean ± SD); or 3) water immersion of the distal extremities (44 ± 1°C). The order of rewarming followed a balanced design. Esophageal temperature, skin temperature, heart rate, oxygen consumption, and heat flux were measured. The warm water produced the highest rewarming rate, 6.1°C·h(-1), 95% CI: 5.3-6.9, compared with Fluidotherapy, 2.2°C·h(-1), 95% CI: 1.4-3.0, and shivering only, 2.0°C·h(-1), 95% CI: 1.2-2.8. The Fluidotherapy and warm water conditions increased skin temperature and inhibited shivering heat production, thus reducing metabolic heat production (166 ± 42 W and 181 ± 45 W, respectively), compared with shivering only (322 ± 142 W). Warm water provided a significantly higher net heat gain (398.0 ± 52 W) than shivering only (288.4 ± 115 W). Fluidotherapy was not as effective as warm water for rewarming mildly hypothermic subjects. Although Fluidotherapy is more portable and technically simpler, it provides a lower rate of rewarming that is similar to shivering only. It does help decrease shivering heat production, lowering energy expenditure and cardiac work, and could be considered in a hospital setting, if convenient. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Physiological Assessment and Behavioral Interaction of Wild and Hatchery Juvenile Salmonids : The Relationship of Fish Size and Growth to Smoltification in Spring Chinook Salmon.

Energy Technology Data Exchange (ETDEWEB)

Beckman, Brian R.; Larsen, Donald A.; Lee-Pawlak, Beeda; Dickhoff, Walton W.

1996-10-01

Experiments were performed to determine the relative influence of size and growth rate on downstream migratory disposition and physiology in yearling spring chinook salmon (Oncorhynchus tshawtscha) smolts. A group of juvenile chinook salmon was size graded into small and large categories with half the fish in each group reared at an elevated temperature, resulting in four distinct treatment groups: Large Warm (LW), Large Cool (LC), Small Warm (SW), and Small Cool (SC). Fish from warm-water treatment groups displayed significantly higher growth rates than cool-water groups. Fish were tagged and released into a natural creek where downstream movement was monitored. For each of the two releases, fish that migrated past a weir within the first 5 days postrelease had significantly higher spring growth rates than fish that did not migrate within that period. Significant differences in length for the same fish were only found in the second release. Also for the second release, fish from the warm water treatment groups were recovered in higher proportions than fish from cool water groups. The results indicate that increased growth rate in the spring has a positive relation to downstream migratory disposition. Furthermore, there is a relation between smolt size and migration; however, this relation is weaker than that found between growth rate and migration.

Water levels shape fishing participation in flood-control reservoirs

Science.gov (United States)

Miranda, Leandro E.; Meals, K. O.

2013-01-01

We examined the relationship between fishing effort (hours fished) and average March–May water level in 3 flood control reservoirs in Mississippi. Fishing effort increased as water level rose, peaked at intermediate water levels, and decreased at high water levels. We suggest that the observed arched-shaped relationship is driven by the shifting influence of fishability (adequacy of the fishing circumstances from an angler's perspective) and catch rate along a water level continuum. Fishability reduces fishing effort during low water, despite the potential for higher catch rates. Conversely, reduced catch rates and fishability at high water also curtail effort. Thus, both high and low water levels seem to discourage fishing effort, whereas anglers seem to favor intermediate water levels. Our results have implications for water level management in reservoirs with large water level fluctuations.

Ecosystem responses to warming and watering in typical and desert steppes

Science.gov (United States)

Xu, Zhenzhu; Hou, Yanhui; Zhang, Lihua; Liu, Tao; Zhou, Guangsheng

2016-10-01

Global warming is projected to continue, leading to intense fluctuations in precipitation and heat waves and thereby affecting the productivity and the relevant biological processes of grassland ecosystems. Here, we determined the functional responses to warming and altered precipitation in both typical and desert steppes. The results showed that watering markedly increased the aboveground net primary productivity (ANPP) in a typical steppe during a drier year and in a desert steppe over two years, whereas warming manipulation had no significant effect. The soil microbial biomass carbon (MBC) and the soil respiration (SR) were increased by watering in both steppes, but the SR was significantly decreased by warming in the desert steppe only. The inorganic nitrogen components varied irregularly, with generally lower levels in the desert steppe. The belowground traits of soil total organic carbon (TOC) and the MBC were more closely associated with the ANPP in the desert than in the typical steppes. The results showed that the desert steppe with lower productivity may respond strongly to precipitation changes, particularly with warming, highlighting the positive effect of adding water with warming. Our study implies that the habitat- and year-specific responses to warming and watering should be considered when predicting an ecosystem’s functional responses under climate change scenarios.

Fish energy budget under ocean warming and flame retardant exposure.

Science.gov (United States)

Anacleto, Patrícia; Figueiredo, Cátia; Baptista, Miguel; Maulvault, Ana Luísa; Camacho, Carolina; Pousão-Ferreira, Pedro; Valente, Luísa M P; Marques, António; Rosa, Rui

2018-07-01

warming and chemical contamination conditions, fish energy budget was greatly affected, which may dictate negative cascading impacts at population and community levels. Further research combining other climate change stressors (e.g. acidification and hypoxia) and emerging chemical contaminants are needed to better understand and forecast such biological effects in a changing ocean. Copyright © 2018 Elsevier Inc. All rights reserved.

Ocean acidification exerts negative effects during warming conditions in a developing Antarctic fish.

Science.gov (United States)

Flynn, Erin E; Bjelde, Brittany E; Miller, Nathan A; Todgham, Anne E

2015-01-01

Anthropogenic CO2 is rapidly causing oceans to become warmer and more acidic, challenging marine ectotherms to respond to simultaneous changes in their environment. While recent work has highlighted that marine fishes, particularly during early development, can be vulnerable to ocean acidification, we lack an understanding of how life-history strategies, ecosystems and concurrent ocean warming interplay with interspecific susceptibility. To address the effects of multiple ocean changes on cold-adapted, slowly developing fishes, we investigated the interactive effects of elevated partial pressure of carbon dioxide (pCO2) and temperature on the embryonic physiology of an Antarctic dragonfish (Gymnodraco acuticeps), with protracted embryogenesis (∼10 months). Using an integrative, experimental approach, our research examined the impacts of near-future warming [-1 (ambient) and 2°C (+3°C)] and ocean acidification [420 (ambient), 650 (moderate) and 1000 μatm pCO2 (high)] on survival, development and metabolic processes over the course of 3 weeks in early development. In the presence of increased pCO2 alone, embryonic mortality did not increase, with greatest overall survival at the highest pCO2. Furthermore, embryos were significantly more likely to be at a later developmental stage at high pCO2 by 3 weeks relative to ambient pCO2. However, in combined warming and ocean acidification scenarios, dragonfish embryos experienced a dose-dependent, synergistic decrease in survival and developed more slowly. We also found significant interactions between temperature, pCO2 and time in aerobic enzyme activity (citrate synthase). Increased temperature alone increased whole-organism metabolic rate (O2 consumption) and developmental rate and slightly decreased osmolality at the cost of increased mortality. Our findings suggest that developing dragonfish are more sensitive to ocean warming and may experience negative physiological effects of ocean acidification only in

Discharge, water temperature, and water quality of Warm Mineral Springs, Sarasota County, Florida: A retrospective analysis

Science.gov (United States)

Metz, Patricia A.

2016-09-27

Warm Mineral Springs, located in southern Sarasota County, Florida, is a warm, highly mineralized, inland spring. Since 1946, a bathing spa has been in operation at the spring, attracting vacationers and health enthusiasts. During the winter months, the warm water attracts manatees to the adjoining spring run and provides vital habitat for these mammals. Well-preserved late Pleistocene to early Holocene-age human and animal bones, artifacts, and plant remains have been found in and around the spring, and indicate the surrounding sinkhole formed more than 12,000 years ago. The spring is a multiuse resource of hydrologic importance, ecological and archeological significance, and economic value to the community.The pool of Warm Mineral Springs has a circular shape that reflects its origin as a sinkhole. The pool measures about 240 feet in diameter at the surface and has a maximum depth of about 205 feet. The sinkhole developed in the sand, clay, and dolostone of the Arcadia Formation of the Miocene-age to Oligocene-age Hawthorn Group. Underlying the Hawthorn Group are Oligocene-age to Eocene-age limestones and dolostones, including the Suwannee Limestone, Ocala Limestone, and Avon Park Formation. Mineralized groundwater, under artesian pressure in the underlying aquifers, fills the remnant sink, and the overflow discharges into Warm Mineral Springs Creek, to Salt Creek, and subsequently into the Myakka River. Aquifers described in the vicinity of Warm Mineral Springs include the surficial aquifer system, the intermediate aquifer system within the Hawthorn Group, and the Upper Floridan aquifer in the Suwannee Limestone, Ocala Limestone, and Avon Park Formation. The Hawthorn Group acts as an upper confining unit of the Upper Floridan aquifer.Groundwater flow paths are inferred from the configuration of the potentiometric surface of the Upper Floridan aquifer for September 2010. Groundwater flow models indicate the downward flow of water into the Upper Floridan aquifer

Possible change in distribution of seaweed, Sargassum horneri, in northeast Asia under A2 scenario of global warming and consequent effect on some fish.

Science.gov (United States)

Komatsu, Teruhisa; Fukuda, Masahiro; Mikami, Atsuko; Mizuno, Shizuha; Kantachumpoo, Attachai; Tanoue, Hideaki; Kawamiya, Michio

2014-08-30

Global warming effects on seaweed beds are already perceptible. Their geographical distributions greatly depend on water temperatures. To predict future geographical distributions of brown alga, Sargassum horneri, forming large beds in the northwestern Pacific, we referred to future monthly surface water temperatures at about 1.1° of longitude and 0.6° of latitude in February and August in 2050 and 2100 simulated by 12 organizations under an A2 scenario of global warming. The southern limit of S. horneri distribution is expected to keep moving northward such that it may broadly disappear from Honshu Island, the Chinese coast, and Korean Peninsula in 2100, when tropical Sargassum species such as Sargassum tenuifolium may not completely replace S. horneri. Thus, their forests in 2100 do not substitute those of S. horneri in 2000. Fishes using the beds and seaweed rafts consisting of S. horneri in East China Sea suffer these disappearances. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Warm water deuterium fractionation in IRAS 16293-2422

DEFF Research Database (Denmark)

Persson, Magnus Vilhelm; Jørgensen, Jes Kristian; van Dishoeck, E. F.

2013-01-01

observations reveal the physical and chemical structure of water vapor close to the protostars on solar-system scales. The red-shifted absorption detected toward source B is indicative of infall. The excitation temperature is consistent with the picture of water ice evaporation close to the protostar. The low......Context. Measuring the water deuterium fractionation in the inner warm regions of low-mass protostars has so far been hampered by poor angular resolution obtainable with single-dish ground- and space-based telescopes. Observations of water isotopologues using (sub)millimeter wavelength...... interferometers have the potential to shed light on this matter. Aims: To measure the water deuterium fractionation in the warm gas of the deeply-embedded protostellar binary IRAS 16293-2422. Methods: Observations toward IRAS 16293-2422 of the 53,2 - 44,1 transition of H218O at 692.07914 GHz from Atacama Large...

Chemical and Hydro-Geologic Analysis of Ikogosi Warm Spring Water in Nigeria

OpenAIRE

Akinola Ikudayisi; Folasade Adeyemo; Josiah Adeyemo

2015-01-01

This study focuses on the hydro-geology and chemical constituents analysis of Ikogosi Warm Spring waters in South West Nigeria. Ikogosi warm spring is a global tourist attraction because it has both warm and cold spring sources. Water samples from the cold spring, warm spring and the meeting point were collected, analyzed and the result shows close similarity in temperature, hydrogen iron concentration (pH), alkalinity, hardness, Calcium, Magnesium, Sodium, Iron, total di...

STREPTOCOCCUS: A WORLDWIDE FISH HEALTH PROBLEM

Science.gov (United States)

Streptococcus iniae and S. agalactiae are important emergent pathogens that affect many fish species worldwide, especially in warm-water regions. In marine and freshwater systems, these Gram-positive bacteria cause significant economic losses, estimated at hundreds of millions of dollars annually. ...

Signature of ocean warming in global fisheries catch.

Science.gov (United States)

Cheung, William W L; Watson, Reg; Pauly, Daniel

2013-05-16

Marine fishes and invertebrates respond to ocean warming through distribution shifts, generally to higher latitudes and deeper waters. Consequently, fisheries should be affected by 'tropicalization' of catch (increasing dominance of warm-water species). However, a signature of such climate-change effects on global fisheries catch has so far not been detected. Here we report such an index, the mean temperature of the catch (MTC), that is calculated from the average inferred temperature preference of exploited species weighted by their annual catch. Our results show that, after accounting for the effects of fishing and large-scale oceanographic variability, global MTC increased at a rate of 0.19 degrees Celsius per decade between 1970 and 2006, and non-tropical MTC increased at a rate of 0.23 degrees Celsius per decade. In tropical areas, MTC increased initially because of the reduction in the proportion of subtropical species catches, but subsequently stabilized as scope for further tropicalization of communities became limited. Changes in MTC in 52 large marine ecosystems, covering the majority of the world's coastal and shelf areas, are significantly and positively related to regional changes in sea surface temperature. This study shows that ocean warming has already affected global fisheries in the past four decades, highlighting the immediate need to develop adaptation plans to minimize the effect of such warming on the economy and food security of coastal communities, particularly in tropical regions.

Evaluation of RSG-GAS purification system and pool warm water layer supplier performance

International Nuclear Information System (INIS)

Sudiyono; Suhadi; Diah-Erlina-Lestari

2005-01-01

Function of RSG-GAS purification system and warm water supplier (KBE 02) are to pick up dissolve activation result and another dirts of warm water layer. To keep quality of water at the decided level. The system is equipped by heater to supply warm water layer on the reactor pool surface the distribution is to reduce radiation level in the operation hall area a speciality on the reactor pool surface. Line KBE 02 tomord beam tube headitty system supplies water necessary to be shielding to beam tube in use off time. Of the RSG-GAS purification system and pool warm water layer performance date can be shown north of water is always in good condition. To require the dechded requirement. Resin live time is two years and then months

Correlated Effects of Ocean Acidification and Warming on Behavioral and Metabolic Traits of a Large Pelagic Fish

Directory of Open Access Journals (Sweden)

Taryn D. Laubenstein

2018-05-01

Full Text Available Ocean acidification and warming are co-occurring stressors, yet their effects on early life stages of large pelagic fishes are not well known. Here, we determined the effects of elevated CO2 and temperature at levels projected for the end of the century on activity levels, boldness, and metabolic traits (i.e., oxygen uptake rates in larval kingfish (Seriola lalandi, a large pelagic fish with a circumglobal distribution. We also examined correlations between these behavioral and physiological traits measured under different treatments. Kingfish were reared from the egg stage to 25 days post-hatch in a full factorial design of ambient and elevated CO2 (~500 µatm and ~1000 µatm and temperature (21 °C and 25 °C. Activity levels were higher in fish from the elevated temperature treatment compared with fish reared under ambient temperature. However, elevated CO2 did not affect activity, and boldness was not affected by either elevated CO2 or temperature. Both elevated CO2 and temperature resulted in increased resting oxygen uptake rates compared to fish reared under ambient conditions, but neither affected maximum oxygen uptake rates nor aerobic scope. Resting oxygen uptake rates and boldness were negatively correlated under ambient temperature, but positively correlated under elevated temperature. Maximum oxygen uptake rates and boldness were also negatively correlated under ambient temperature. These findings suggest that elevated temperature has a greater impact on behavioral and physiological traits of larval kingfish than elevated CO2. However, elevated CO2 exposure did increase resting oxygen uptake rates and interact with temperature in complex ways. Our results provide novel behavioral and physiological data on the responses of the larval stage of a large pelagic fish to ocean acidification and warming conditions, demonstrate correlations between these traits, and suggest that these correlations could influence the direction and pace of

Warm Water Pathways in the Northeastern North Atlantic ACCE RAFOS Float Data Report

National Research Council Canada - National Science Library

Furey, Heather

2001-01-01

...). The RAFOS float component of ACCE, entitled "Warm Water Pathways and Intergyre Exchange in the Northeastern North Atlantic", was designed to measure the warm water currents entering the northeastern...

Cold-water fishes and climate change in North America

Science.gov (United States)

J. E. Williams; Daniel Isaak; J. Imhof; D. A. Hendrickson; J. R. McMillan

2015-01-01

Trout, salmon, grayling and whitefishes (Salmonidae) are among the most ecologically and economically important fishes. They also are among the most vulnerable to global warming, and increasing drought, floods, and wildfires. In North America, salmonids occur from central Mexico northward along coastal regions and mountainous interiors to the Arctic Plains. A...

Freshwater and fish

International Nuclear Information System (INIS)

Saxen, R.

1997-01-01

Severe radioactive contamination of the freshwater environment could have serious consequences for both drinking water and fish. Most of the Nordic countries have an abundance of freshwater lakes and rivers. Finland alone has about 56,000 lakes, each with a surface area of 1 hectare or more. Nearly 10% of Finland's surface is covered with lakes and rivers. In Sweden, about 9% of the surface area is freshwater, in Norway about 5%, and in Denmark only about 2%. Freshwater plays a minor role in Iceland, but even there numerous rivers discharge from the volcanic soils to the Ocean. Cs-137 and 90 Sr are likely to be the most important radionuclides with respect to long term radioactive contamination of freshwater. If radioactive deposition occurs in the absence of snow and ice radionuclides will contaminate the surface water directly and may rapidly enter the aquatic food chain. Fish which eat contaminated plankton become contaminated almost immediately. Deposition during summer increases the transfer for radionuclides to fish since fish metabolism is faster during the warm season. During the cold period, fish metabolism is slow and thus uptake and excretion of radiocaesium are also slow. (EG)

Partition of selected food preservatives in fish oil-water systems

DEFF Research Database (Denmark)

Cheng, Hongyuan; Friis, Alan; Leth, Torben

2010-01-01

The partition coefficients (Kow) of benzoic acid and sorbic acid in systems of fish oil (sand eel)–water, fish oil–buffer solution, rape oil–water and olive oil–water were experimentally determined in a temperature range from 5 to 43 °C and pH from 4.5 to 6.5 °C. The dimerization of benzoic acid...... in fish oil–water system was observed at 25 °C. Two modifications have been made to the Nordic Food Analysis Standard for the determination of sorbic acid by HPLC. The experimental results show that the Kow of benzoic acid and sorbic acid in fish oil–buffer system is ca. 100 times lower than that in fish...... oil–water system. The Kow values of benzoic acid and sorbic acid in fish oil and water system decrease with increasing system pH values. The partition coefficients of plant origin and fish origin oils are in the same order of magnitude even though their molecular structures are very different....

Continental paleothermometry and seasonality using the isotopic composition of aragonitic otoliths of freshwater fishes

Science.gov (United States)

Patterson, William P.; Smith, Gerald R.; Lohmann, Kyger C.

To investigate the applicability of oxygen isotope themometry using fish aragonite, the δ18O values of paired otolith and water samples were analyzed from six large modem temperate lakes. Otoliths are accretionaiy aragonitic structures which are precipitated within the sacculus of fish ears. Deep-water obligate benthic species from the hypolimnion of the Laurentian Great Lakes of North America and Lake Baikal, Siberia, provided cold-water end member values for aragonite δ18O. Warm-water values were obtained from naturally grown warm-water stenothermic species and from fish grown in aquaria under controlled conditions. These two groups, which represent growth over a temperature range of 3.2-30.3°C. were employed to determine the oxygen isotope temperature fractionation relationship for aragonite-water: 103lnα = 18.56 (±0.319)·(103)T-1 K -33.49 (±0.307). Empirical calibration of a fish aragonite thennometry equation allows its direct application to studies of paleoclimate. For example, high-resolution sampling of shallow-water eurythermic species coupled with a knowledge of the isotopic composition of meteoric waters can be used to determine seasonal temperature variation. This approach was tested using a modem shallow-water eurythermic species from Sandusky Bay, Lake Erie. Temperatures calculated from carbonate composition agree with meteorological records from the Sandusky Bay weather station for the same time period.

EFFECTS OF FISHING ON THE SIZE AND DOMINANCE ...

African Journals Online (AJOL)

... waters of the Western Cape show a trend towards increasing dominance with increased effort, whereas the warm-temperate regions show decreased dominance with increased fishing pressure. These findings have important consequences for fisheries management, because not only are several stocks badly overfished, ...

Impact of using raw or fermented manure as fish feed on microbial quality of water and fish

Directory of Open Access Journals (Sweden)

Nagham Elsaidy

2015-01-01

Full Text Available The microbial water and fish quality was assessed due to feeding of chicken manure (CM and fermented chicken manure (FCM to fish in ponds, using Nile tilapia (Oreochromis niloticus which were classified into 7 groups (G. Each group received different mixtures of CM or FCM with fish ration (FR, 0:100, 25:75, 50:50 and 100:0 (%CM or FCM:% FR. The obtained results revealed that total bacterial count (TBC and total coliform count (TCC were significantly high at P ⩽ 0.05 in CM than both FCM and fish ration (FR. Escherichia coli and Salmonella were isolated from CM but not from FCM or FR. Additionally, TBC and TCC were significantly high at P ⩽ 0.05 at water and fish samples raised at CM ponds followed by FCM ponds in comparison with FR. Both E. coli and Salmonella were isolated from water and fish raised in ponds receiving either CM or FCM with higher incidence in those with CM. However all water and fish samples examined were free from E-coli O157: H7. The obtained results, proved the influence of CM on water and fish quality and recommend the use of FCM as a bacteriologically safe fish pond fertilizer.

Warm water upwelling in the Cenozoic Era

Science.gov (United States)

Zhang, Y.

2017-12-01

Modern observations show that the occurrence of wind-driven upwelling is often tied to cold sea surface temperatures (SSTs). However, SST reconstructions indicate that globally, the upwelling regions were much warmer in the Miocene and Pliocene. This questions the overall strength of deep-water upwelling in the geological past, with important implications for the associated atmospheric, climatic and biogeochemical processes, and the fate of upwelling regions in a high-CO2 world. We recently showed that the eastern equatorial Pacific (EEP) was characterized by strong air-sea disequilibrium of CO2 during the late Miocene - Pliocene. Combined with export productivity proxies, we interpreted these as signs of vigorous upwelling. The upwelled waters were nutrient- and CO2-rich, but warm. The cause of the "excess" warming in the upwelling regions is linked to the source waters which originated from the higher latitudes. In other words, the reduced east (upwelling) to west (non-upwelling) temperature gradients along the equator in major ocean basins are rooted in the reduced meridional temperature gradients. To further test this hypothesis, we examine the history of the EEP and temperature gradients during the even-warmer Eocene - middle Miocene.

Transport of Mars atmospheric water into high northern latitudes during a polar warming

Science.gov (United States)

Barnes, J. R.; Hollingsworth, J. L.

1988-01-01

Several numerical experiments were conducted with a simplified tracer transport model in order to attempt to examine the poleward transport of Mars atmospheric water during a polar warming like that which occurred during the winter solstice dust storm of 1977. The flow for the transport experiments was taken from numerical simulations with a nonlinear beta-plane dynamical model. Previous studies with this model have demonstrated that a polar warming having essential characteristics like those observed during the 1977 dust storm can be produced by a planetary wave mechanism analogous to that responsible for terrestrial sudden stratospheric warmings. Several numerical experiments intended to simulate water transport in the absence of any condensation were carried out. These experiments indicate that the flow during a polar warming can transport very substantial amounts of water to high northern latitudes, given that the water does not condense and fall out before reaching the polar region.

Par Pond Fish, Water, and Sediment Chemistry

International Nuclear Information System (INIS)

Paller, M.H.; Wike, L.D.

1996-06-01

The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond

Par Pond Fish, Water, and Sediment Chemistry

Energy Technology Data Exchange (ETDEWEB)

Paller, M.H. [Westinghouse Savannah River Company, AIKEN, SC (United States); Wike, L.D.

1996-06-01

The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

Salinity and temperature tolerance of an emergent alien species, the Amazon fish Astronotus ocellatus

Science.gov (United States)

Gutierrel, Silvia M M; Schofield, Pam; Prodocimo, Viviane

2016-01-01

Astronotus ocellatus (oscar), is native to the Amazon basin and, although it has been introduced to many countries, little is known regarding its tolerances for salinity and temperature. In this report, we provide data on the tolerance of A. ocellatus to abrupt and gradual changes in salinity, its high and low temperature tolerance, and information on how salinity, temperature, and fish size interact to affect survival. Fish were able to survive abrupt transfer to salinities as high as 16 ppt with no mortality. When salinity change was gradual (2 ppt/day), fish in the warm-temperature experiment (28°C) survived longer than fish in the cool-temperature experiment (18°C). Larger fish survived longer than smaller ones at the higher salinities when the temperature was warm, but when the temperature was cool fish size had little effect on survival. In the temperature-tolerance experiments, fish survived from 9 to 41°C for short periods of time. Overall, the species showed a wide range of temperature and salinity tolerance. Thus, in spite of the tropical freshwater origin of this species, physiological stress is not likely to hinder its dispersal to brackish waters, especially when temperatures are warm.

Managing water to protect fish: A review of California's environmental water account, 2001-2005

Science.gov (United States)

Brown, L.R.; Kimmerer, W.; Brown, R.

2009-01-01

The Sacramento-San Joaquin Delta, the landward reach of the San Francisco Estuary, provides habitat for threatened delta smelt, endangered winter-run Chinook salmon, and other species of concern. It is also the location of huge freshwater diversion facilities that entrain large numbers of fish. Reducing the entrainment of listed fishes into these facilities has required curtailment of pumping, reducing the reliability of water deliveries. We reviewed the first 5 years (2001-2005) of the Environmental Water Account (EWA), a program instituted to resolve conflicts between protecting listed fishes and providing a reliable water supply. The EWA provided fishery agencies with control over 0.2-0.4 km3 of water to be used for fish protection at no cost to users of exported water, and fish agencies guaranteed no disruption of water supply for fish protection. The EWA was successful in reducing uncertainty in water supply; however, its contribution to the recovery of listed fishes was unclear. We estimated the effectiveness of the EWA to be modest, increasing the survival of winter-run Chinook salmon by 0-6% (dependent on prescreen mortality), adult delta smelt by 0-1%, and juvenile delta smelt by 2-4%. Allocating EWA water for a single life stage of one species could provide larger gains in survival. An optimally allocated EWA of equal size to the median of the first 5 years could increase abundance of juvenile delta smelt up to 7% in the springs of dry years. If the EWA is to become a long-term program, estimates of efficacy should be refined. If the program is to be held accountable for quantitative increases in fish populations, it will be necessary to integrate scientific, possibly experimental, approaches. ?? 2008 Springer Science+Business Media, LLC.

Molecular Plasticity under Ocean Warming: Proteomics and Fitness Data Provides Clues for a Better Understanding of the Thermal Tolerance in Fish.

Science.gov (United States)

Madeira, Diana; Araújo, José E; Vitorino, Rui; Costa, Pedro M; Capelo, José L; Vinagre, Catarina; Diniz, Mário S

2017-01-01

Ocean warming is known to alter the performance and fitness of marine organisms albeit the proteome underpinnings of species thermal tolerance are still largely unknown. In this 1-month experiment we assessed the vulnerability of the gilt-head sea bream Sparus aurata , taken here as a biological model for some key fisheries species, to ocean warming (control 18°C, nursery ground temperature 24°C and heat wave 30°C). Survival was impaired after 28 days, mainly at 30°C although fishes' condition was unaltered. Muscle proteome modulation was assessed at 14 and 21 days, showing that protein expression profiles were similar between fish exposed to 18 and 24°C, differing from fish exposed to 30°C. Fish subjected to 24°C showed an enhanced glycolytic potential and decreased glycogenolysis mainly at 14 days of exposure. Fish subjected to 30°C also showed enhanced glycolytic potential and up-regulated proteins related to gene expression, cellular stress response (CSR), and homeostasis (mostly cytoskeletal dynamics, acid-base balance, chaperoning). However, inflammatory processes were elicited at 21 days along with a down-regulation of the tricarboxylic acid cycle. Thus, juvenile fish seem able to acclimate to 24°C but possibly not to 30°C, which is the predicted temperature for estuaries during heat waves by the year 2100. This may be related with increasing constraints on organism physiology associated with metabolic scope available for performance and fitness at higher temperatures. Consequently, recruitment of commercial sea breams may be in jeopardy, highlighting the need for improved management plans for fish stocks.

Molecular Plasticity under Ocean Warming: Proteomics and Fitness Data Provides Clues for a Better Understanding of the Thermal Tolerance in Fish

Directory of Open Access Journals (Sweden)

Diana Madeira

2017-10-01

Full Text Available Ocean warming is known to alter the performance and fitness of marine organisms albeit the proteome underpinnings of species thermal tolerance are still largely unknown. In this 1-month experiment we assessed the vulnerability of the gilt-head sea bream Sparus aurata, taken here as a biological model for some key fisheries species, to ocean warming (control 18°C, nursery ground temperature 24°C and heat wave 30°C. Survival was impaired after 28 days, mainly at 30°C although fishes' condition was unaltered. Muscle proteome modulation was assessed at 14 and 21 days, showing that protein expression profiles were similar between fish exposed to 18 and 24°C, differing from fish exposed to 30°C. Fish subjected to 24°C showed an enhanced glycolytic potential and decreased glycogenolysis mainly at 14 days of exposure. Fish subjected to 30°C also showed enhanced glycolytic potential and up-regulated proteins related to gene expression, cellular stress response (CSR, and homeostasis (mostly cytoskeletal dynamics, acid-base balance, chaperoning. However, inflammatory processes were elicited at 21 days along with a down-regulation of the tricarboxylic acid cycle. Thus, juvenile fish seem able to acclimate to 24°C but possibly not to 30°C, which is the predicted temperature for estuaries during heat waves by the year 2100. This may be related with increasing constraints on organism physiology associated with metabolic scope available for performance and fitness at higher temperatures. Consequently, recruitment of commercial sea breams may be in jeopardy, highlighting the need for improved management plans for fish stocks.

Experimental and natural warming elevates mercury concentrations in estuarine fish.

Directory of Open Access Journals (Sweden)

Jennifer A Dijkstra

Full Text Available Marine food webs are the most important link between the global contaminant, methylmercury (MeHg, and human exposure through consumption of seafood. Warming temperatures may increase human exposure to MeHg, a potent neurotoxin, by increasing MeHg production as well as bioaccumulation and trophic transfer through marine food webs. Studies of the effects of temperature on MeHg bioaccumulation are rare and no study has specifically related temperature to MeHg fate by linking laboratory experiments with natural field manipulations in coastal ecosystems. We performed laboratory and field experiments on MeHg accumulation under varying temperature regimes using the killifish, Fundulus heteroclitus. Temperature treatments were established in salt pools on a coastal salt marsh using a natural temperature gradient where killifish fed on natural food sources. Temperatures were manipulated across a wider range in laboratory experiments with killifish exposed to MeHg enriched food. In both laboratory microcosms and field mesocosms, MeHg concentrations in killifish significantly increased at elevated temperatures. Moreover, in field experiments, other ancillary variables (salinity, MeHg in sediment, etc. did not relate to MeHg bioaccumulation. Modeling of laboratory experimental results suggested increases in metabolic rate as a driving factor. The elevated temperatures we tested are consistent with predicted trends in climate warming, and indicate that in the absence of confounding factors, warmer sea surface temperatures could result in greater in bioaccumulation of MeHg in fish, and consequently, increased human exposure.

Warming by immersion or exercise affects initial cooling rate during subsequent cold water immersion.

Science.gov (United States)

Scott, Chris G; Ducharme, Michel B; Haman, François; Kenny, Glen P

2004-11-01

We examined the effect of prior heating, by exercise and warm-water immersion, on core cooling rates in individuals rendered mildly hypothermic by immersion in cold water. There were seven male subjects who were randomly assigned to one of three groups: 1) seated rest for 15 min (control); 2) cycling ergometry for 15 min at 70% Vo2 peak (active warming); or 3) immersion in a circulated bath at 40 degrees C to an esophageal temperature (Tes) similar to that at the end of exercise (passive warming). Subjects were then immersed in 7 degrees C water to a Tes of 34.5 degrees C. Initial Tes cooling rates (initial approximately 6 min cooling) differed significantly among the treatment conditions (0.074 +/- 0.045, 0.129 +/- 0.076, and 0.348 +/- 0.117 degrees C x min(-1) for control, active, and passive warming conditions, respectively); however, secondary cooling rates (rates following initial approximately 6 min cooling to the end of immersion) were not different between treatments (average of 0.102 +/- 0.085 degrees C x min(-1)). Overall Tes cooling rates during the full immersion period differed significantly and were 0.067 +/- 0.047, 0.085 +/- 0.045, and 0.209 +/- 0.131 degrees C x min(-1) for control, active, and passive warming, respectively. These results suggest that prior warming by both active and, to a greater extent, passive warming, may predispose a person to greater heat loss and to experience a larger decline in core temperature when subsequently exposed to cold water. Thus, functional time and possibly survival time could be reduced when cold water immersion is preceded by whole-body passive warming, and to a lesser degree by active warming.

Impact of global warming and rising CO2 levels on coral reef fishes: what hope for the future?

Science.gov (United States)

Munday, Philip L; McCormick, Mark I; Nilsson, Göran E

2012-11-15

Average sea-surface temperature and the amount of CO(2) dissolved in the ocean are rising as a result of increasing concentrations of atmospheric CO(2). Many coral reef fishes appear to be living close to their thermal optimum, and for some of them, even relatively moderate increases in temperature (2-4°C) lead to significant reductions in aerobic scope. Reduced aerobic capacity could affect population sustainability because less energy can be devoted to feeding and reproduction. Coral reef fishes seem to have limited capacity to acclimate to elevated temperature as adults, but recent research shows that developmental and transgenerational plasticity occur, which might enable some species to adjust to rising ocean temperatures. Predicted increases in P(CO(2)), and associated ocean acidification, can also influence the aerobic scope of coral reef fishes, although there is considerable interspecific variation, with some species exhibiting a decline and others an increase in aerobic scope at near-future CO(2) levels. As with thermal effects, there are transgenerational changes in response to elevated CO(2) that could mitigate impacts of high CO(2) on the growth and survival of reef fishes. An unexpected discovery is that elevated CO(2) has a dramatic effect on a wide range of behaviours and sensory responses of reef fishes, with consequences for the timing of settlement, habitat selection, predator avoidance and individual fitness. The underlying physiological mechanism appears to be the interference of acid-base regulatory processes with brain neurotransmitter function. Differences in the sensitivity of species and populations to global warming and rising CO(2) have been identified that will lead to changes in fish community structure as the oceans warm and becomes more acidic; however, the prospect for acclimation and adaptation of populations to these threats also needs to be considered. Ultimately, it will be the capacity for species to adjust to environmental

Ocean cleaning stations under a changing climate: biological responses of tropical and temperate fish-cleaner shrimp to global warming.

Science.gov (United States)

Rosa, Rui; Lopes, Ana Rita; Pimentel, Marta; Faleiro, Filipa; Baptista, Miguel; Trübenbach, Katja; Narciso, Luis; Dionísio, Gisela; Pegado, Maria Rita; Repolho, Tiago; Calado, Ricardo; Diniz, Mário

2014-10-01

Cleaning symbioses play an important role in the health of certain coastal marine communities. These interspecific associations often occur at specific sites (cleaning stations) where a cleaner organism (commonly a fish or shrimp) removes ectoparasites/damaged tissue from a 'client' (a larger cooperating fish). At present, the potential impact of climate change on the fitness of cleaner organisms remains unknown. This study investigated the physiological and biochemical responses of tropical (Lysmata amboinensis) and temperate (L. seticaudata) cleaner shrimp to global warming. Specifically, thermal limits (CTMax), metabolic rates, thermal sensitivity, heat shock response (HSR), lipid peroxidation [malondialdehyde (MDA) concentration], lactate levels, antioxidant (GST, SOD and catalase) and digestive enzyme activities (trypsin and alkaline phosphatase) at current and warming (+3 °C) temperature conditions. In contrast to the temperate species, CTMax values decreased significantly from current (24-27 °C) to warming temperature conditions (30 °C) for the tropical shrimp, where metabolic thermal sensitivity was affected and the HSR was significantly reduced. MDA levels in tropical shrimp increased dramatically, indicating extreme cellular lipid peroxidation, which was not observed in the temperate shrimp. Lactate levels, GST and SOD activities were significantly enhanced within the muscle tissue of the tropical species. Digestive enzyme activities in the hepatopancreas of both species were significantly decreased by warmer temperatures. Our data suggest that the tropical cleaner shrimp will be more vulnerable to global warming than the temperate Lysmata seticaudata; the latter evolved in a relatively unstable environment with seasonal thermal variations that may have conferred greater adaptive plasticity. Thus, tropical cleaning symbioses may be challenged at a greater degree by warming-related anthropogenic forcing, with potential cascading effects on the health

Uptake of {sup 137}Cs by fresh water fish

Energy Technology Data Exchange (ETDEWEB)

Man, C.K.; Kwok, Y.H

2000-02-01

The uptake and discharge rates of {sup 137}Cs by fresh water fish at different radionuclide concentrations have been studied. A dual compartment model was used to fit the experimental data. The discharge rates have been found to be negligible for the duration of the experiment of 10 days. The uptake rates were independent of radionuclide concentrations for a particular type of fresh water fish and were different for different types of fish. The uptake rates of carp, tilapia and snakehead were 1.58, 1.66 and 2.23, in unit of 10{sup -6} h{sup -1}, respectively. It was also estimated that the consumption of fresh water fish, even if the water were contaminated as much as that in the Chernobyl accident, leads to negligible latent cancer fatality to the Hong Kong population.

137Cs in water and fishes in FInland during 1986-1991

International Nuclear Information System (INIS)

Saxen, R.

1992-01-01

By following changes in 137 Cs concentration, during a time period, in water and fish it is possible to estimate the halving-times of the nuclides. Examples are given of estimations of halving-times for 137 Cs in water and fish in individual lakes, some larger surface water areas and in areas with the highest rainfall in Finland. Transfer coefficients from water to fish are given as a function of time in some lakes. Transfer coefficients from precipitation to fish have been calculated on an annual basis in the case of some species of fish. (AB)

Cooling-water amounts, temperature, and the environment

International Nuclear Information System (INIS)

Koops, F.B.J.; Donze, M.; Hadderingh, R.H.

1979-01-01

The release of heat from power plants into a water can take place with relative small quantities of cooling water, highly warmed up accordingly, or with large quantities of cooling water slightly warmed up. The utilization of cooling water is bound to certain guidelines established by the authorities. With the intention to protect the environment, the admissable temperatures and warming-up have been strictly limited by the authorities. In the Netherlands, we have presently temporary cooling water guidelines which allow a max. temperature of the cooling water in the cooling cycle of 30 0 C and a maximum admissible temperature rise in the condenser between 7 0 C during summer and 15 0 C during winter. It has also been determined in these requirements how much cooling water at least has to be used to discharge a specified quantity of heat. Plankton, spawn and young fish are dragged with the cooling water. Harm to these organisms can be caused mechanically by pumps, sieves and the condenser or they can be harmed by the temperature rise in the condenser. Investigations showed that mechanical harm to spawn and young fish in the cooling water flow should not be ignored, and that detectable harm to plankton organisms takes place only at water temperatures above 32 0 C. The cooling water consumption can therefore be optimised as follows: The solution of a greater temperature increase and a slightly higher value for the temperature maximum can reduce the cooling water quantity. This reduction of the cooling water quantity reduces the destruction of the fish quantity, which gets into the cooling water system, especially during the summer. If the temperature rise and the temperature itself are not selected too high, the destruction of fish may be reduced without causing serious damage to the plankton. (orig.) [de

Combined production of fish and plants in recirculating water

Energy Technology Data Exchange (ETDEWEB)

Naegel, L.C.A.

1977-01-01

A pilot plant of ca 2000 l of recirculating fresh water for intensive fish production was constructed in a controlled-environment greenhouse. The feasibility was examined of using nutrients from fish wastewater, mainly oxidized nitrogenous compounds, for plant production, combined with an activated sludge system for water purification. The reduction of nitrates, formed during the extended aeration process by nitrifying bacteria, was not sufficient by higher plants and unicellular algae alone to reduce the nitrate concentration in our system significantly. An additional microbial denitrification step had to be included to effect maximal decrease in nitrogenous compounds. For fish culture in the pilot plant Tilapia mossambica and Cyprinus carpio were chosen as experimental fishes. Both fish species showed significant weight increases during the course of the experiment. Ice-lettuce and tomatoes were tested both in recirculating water and in batch culture. The unicellular algae Scenedesmus spp. were grown in a non-sterile batch culture. All plants grew well in the wastewater without additional nutrients. Determination of the physical and chemical parameters for optimum water purification, the most suitable ratio of denitrification by plants and by microorganisms, and the most favourable fish and plant species for combined culture in recirculating water are important and of current interest in view of the increasing demand for clean, fresh water, and the pressing need to find new ways of producing protein for human nutrition under prevailing conditions of an exponentially expanding world population.

Does the water reuse affect the fish growth, welfare quality?

Directory of Open Access Journals (Sweden)

Štěpán Lang

2012-01-01

Full Text Available The fish production in aquaculture is growing from year to year. However capacities of current aquaculture facilities are limited. So the need of intensification of old facilities and building new intensive facilities is obvious. The high intensity of fish culture generates some questions. Could water reuse affect fish growth, welfare, health or quality of final product? A lot of research was performed for this issue but just a few works compared water reuse systems (RAS versus flow thru systems (FTS. A problem with CO2 oversaturation was solved by shallow diffusers. Fin erosion seems to be a problem of high stocking density and system hygienic but it is not related directly to water reuse. A few papers were written about biochemical blood stress markers but it was mostly aimed to acute crowding or changes were found at extreme stocking densities over 124 kg.m3 for rainbow trout and 70 kg.m3 for sea bass. The fish are able to accustom to increased noise produced by RAS equipment very fast so it don’t affect fish negatively. There wasn’t found any prove of main water reuse to fish influence in the available literature. All results indicates that if the ecological parameters are kept in natural range for the fish reared in RAS, there is no negative effect of water reuse on fish.

Warming of the Global Ocean: Spatial Structure and Water-Mass Trends

Science.gov (United States)

Hakkinen, Sirpa; Rhines, Peter B.; Worthen, Denise L.

2016-01-01

This study investigates the multidecadal warming and interannual-to-decadal heat content changes in the upper ocean (0-700 m), focusing on vertical and horizontal patterns of variability. These results support a nearly monotonic warming over much of the World Ocean, with a shift toward Southern Hemisphere warming during the well-observed past decade. This is based on objectively analyzed gridded observational datasets and on a modeled state estimate. Besides the surface warming, a warming climate also has a subsurface effect manifesting as a strong deepening of the midthermocline isopycnals, which can be diagnosed directly from hydrographic data. This deepening appears to be a result of heat entering via subduction and spreading laterally from the high-latitude ventilation regions of subtropical mode waters. The basin-average multidecadal warming mainly expands the subtropical mode water volume, with weak changes in the temperature-salinity (u-S) relationship (known as ''spice'' variability). However, the spice contribution to the heat content can be locally large, for example in Southern Hemisphere. Multidecadal isopycnal sinking has been strongest over the southern basins and weaker elsewhere with the exception of the Gulf Stream/North Atlantic Current/subtropical recirculation gyre. At interannual to decadal time scales, wind-driven sinking and shoaling of density surfaces still dominate ocean heat content changes, while the contribution from temperature changes along density surfaces tends to decrease as time scales shorten.

Eutrophic waters, algal bloom and fish kill in fish farming areas in Bolinao, Pangasinan, Philippines

International Nuclear Information System (INIS)

San Diego-McGlone, Maria Lourdes; Azanza, Rhodora V.; Villanoy, Cesar L.; Jacinto, Gil S.

2008-01-01

The coastal waters of Bolinao, Pangasinan, Philippines experienced environmental changes over a 10-year period (1995-2005), the most significant effect of which was the major fish kill event in 2002 that coincided with the first reported Philippine bloom of a dinoflagellate Prorocentrum minimum. Days before the bloom, dissolved oxygen was <2.0 mg/l in the waters that were stratified. These conditions may be linked to the uncontrolled proliferation of fish pens and cages to more than double the allowable limit of 544 units for Bolinao waters. Mariculture activities release organic matter from unconsumed feed and fecal material that accumulate in the water and sediments. In over 10 years, water quality conditions have become eutrophic with ammonia increasing by 56%, nitrite by 35%, nitrate by 90%, and phosphate by 67%. The addition of more fish pens and cages placed additional stress to this poorly flushed, shallow area that affected water quality due to changes in the water residence time

Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems.

Science.gov (United States)

Rix, Laura; de Goeij, Jasper M; Mueller, Christina E; Struck, Ulrich; Middelburg, Jack J; van Duyl, Fleur C; Al-Horani, Fuad A; Wild, Christian; Naumann, Malik S; van Oevelen, Dick

2016-01-07

Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrients in DOM to higher trophic levels on Caribbean reefs via the so-called sponge loop. Coral mucus may be a major DOM source for the sponge loop, but mucus uptake by sponges has not been demonstrated. Here we used laboratory stable isotope tracer experiments to show the transfer of coral mucus into the bulk tissue and phospholipid fatty acids of the warm-water sponge Mycale fistulifera and cold-water sponge Hymedesmia coriacea, demonstrating a direct trophic link between corals and reef sponges. Furthermore, 21-40% of the mucus carbon and 32-39% of the nitrogen assimilated by the sponges was subsequently released as detritus, confirming a sponge loop on Red Sea warm-water and north Atlantic cold-water coral reefs. The presence of a sponge loop in two vastly different reef environments suggests it is a ubiquitous feature of reef ecosystems contributing to the high biogeochemical cycling that may enable coral reefs to thrive in nutrient-limited (warm-water) and energy-limited (cold-water) environments.

Warming combined with more extreme precipitation regimes modifies the water sources used by trees.

Science.gov (United States)

Grossiord, Charlotte; Sevanto, Sanna; Dawson, Todd E; Adams, Henry D; Collins, Adam D; Dickman, Lee T; Newman, Brent D; Stockton, Elizabeth A; McDowell, Nate G

2017-01-01

The persistence of vegetation under climate change will depend on a plant's capacity to exploit water resources. We analyzed water source dynamics in piñon pine and juniper trees subjected to precipitation reduction, atmospheric warming, and to both simultaneously. Piñon and juniper exhibited different and opposite shifts in water uptake depth in response to experimental stress and background climate over 3 yr. During a dry summer, juniper responded to warming with a shift to shallow water sources, whereas piñon pine responded to precipitation reduction with a shift to deeper sources in autumn. In normal and wet summers, both species responded to precipitation reduction, but juniper increased deep water uptake and piñon increased shallow water uptake. Shifts in the utilization of water sources were associated with reduced stomatal conductance and photosynthesis, suggesting that belowground compensation in response to warming and water reduction did not alleviate stress impacts for gas exchange. We have demonstrated that predicted climate change could modify water sources of trees. Warming impairs juniper uptake of deep sources during extended dry periods. Precipitation reduction alters the uptake of shallow sources following extended droughts for piñon. Shifts in water sources may not compensate for climate change impacts on tree physiology. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Application of solar radiation for heating and preparation of warm water in an individual house

International Nuclear Information System (INIS)

Kozak, Tadeeusz; Majchrzycka, Anna

2009-01-01

The paper is aimed at analysis of application of the solar collectors array for preparing of warm water and space heating in an individual house. Keywords: application of solar radiation, preparation of warm water, heating

Fish larvae from the Canary region in autumn

Directory of Open Access Journals (Sweden)

J. M. Rodríguez

2000-03-01

Full Text Available In this paper, the taxonomic composition of the fish larvae community in the Canary region in autumn 1991 is presented. In total, 8699 larvae belonging to 58 fish families were studied. 176 taxonomic groups were identified, 149 at species level and the rest were identified at a higher level. The most numerous family and the one that presented the greatest number of species was Myctophidae. The most frequently caught species was Cyclothone braueri. The taxonomic composition (at family level of the fish larvae community, dominated by four mesopelagic families, was typical of oceanic regions of warm waters. The most remarkable feature of the fish larvae community was its high specific diversity.

Assessment of microcystins in lake water and fish (Mugilidae, Liza sp.) in the largest Spanish coastal lake.

Science.gov (United States)

Romo, Susana; Fernández, Francisca; Ouahid, Youness; Barón-Sola, Ángel

2012-01-01

Cyanobacteria dominance and cyanotoxin production can become major threats to humans and aquatic life, especially in warm shallow lakes, which are often dominated by cyanobacteria. This study investigates the occurrence and distribution of microcystins (MCYST) in water, cell-bound and in the tissues of the commercial mugilid Liza sp. in the largest, coastal, Spanish Mediterranean lake (Albufera of Valencia). This is the first report concerning microcystin accumulation in tissues of mugilid fish species. Considerable amounts of microcystins were found in the water and seston, which correlated with development of Microcystis aeruginosa populations in the lake. The MCYST concentrations found in Lake Albufera (mean 1.7 and 17 μg/L and maximum 16 and 120 μg/L in water and seston, respectively) exceeded by one to two orders of magnitude the guideline levels proposed by the World Health Organization and were higher than that reported in other lakes of the Mediterranean zone. The presence of MCYST was found in all the fishes studied and accumulated differently among tissues of the commercial species Liza sp. Toxin accumulation in fish tissues showed that although the target organ for MCYST was the liver, high concentrations of microcystins were also found in other analysed tissues (liver>intestine>gills>muscle). Human tolerable daily intake for microcystins is assessed relative to the WHO guidelines, and potential toxicological risks for humans, wildlife and related ecosystems of the lake are discussed.

Levels of toxaphene congeners in fish from Danish waters

DEFF Research Database (Denmark)

Fromberg, Arvid; Cederberg, Tommy Licht; Hilbert, G.

2000-01-01

The levels of toxaphene congeners, in addition to PCB congeners and organochlorine pesticides, were determined in various fish samples from different Danish waters. While PCB-153 and p,p'-DDE show different levels depending on the fishing area, with highest levels in fish from the Western Baltic...... Sea, toxaphene was detected in all the samples investigated at a more constant level. The distribution of the three toxaphene congeners Parlar #26, #50 and #62 depends on the fishing area, with the Western Baltic Sea being different from the other waters by having almost equal levels of toxaphene...

Distribution and Bioaccumulation of I-131 Within The Water-Fish System

International Nuclear Information System (INIS)

Darussalam, M; Wijaya, DGO; Sutrisno

1996-01-01

Distribution and Bioaccumulation of I-131 Within The Water-Fish System. As one of fission products, radioiodine I-131 potentially become a pollutant either resulted froma fallout or radioactive waste. Therefore, special interest has been given to handle I-131 starting from its production implementation and its waste management. The observations in this research have been focussed on distribution and bio accumulation of I-131 within the water-fish systems. Some number of Tilapia fish were put in aquaria containing I-131 contamined water with certain radioactivity concentration. Within time interval of 0, 6, 24, 48 and 72 hours after treatment the radioactivities of water media. fish and their organs have been measured. The results show that the radioactivity percentage different water media containing different I-131 concentration tend to have similar patterns. Meanwhile, the I-131 concentrations of fish and their organs were varied with similar patterns for different I-131 content in water media

Hunt warm, rest cool: bioenergetic strategy underlying diel vertical migration of a benthic shark.

Science.gov (United States)

Sims, David W; Wearmouth, Victoria J; Southall, Emily J; Hill, Jacqueline M; Moore, Pippa; Rawlinson, Kate; Hutchinson, Neil; Budd, Georgina C; Righton, David; Metcalfe, Julian D; Nash, Jon P; Morritt, David

2006-01-01

1. Diel vertical migration (DVM) is a widespread phenomenon among marine and freshwater organisms and many studies with various taxa have sought to understand its adaptive significance. Among crustacean zooplankton and juveniles of some fish species DVM is accepted widely as an antipredator behaviour, but little is known about its adaptive value for relatively large-bodied, adult predatory fish such as sharks. Moreover, the majority of studies have focused on pelagic forms, which raises the question of whether DVM occurs in bottom-living predators. 2. To investigate DVM in benthic predatory fish in the marine environment and to determine why it might occur we tracked movements of adult male dogfish (Scyliorhinus canicula) by short- and long-term acoustic and archival telemetry. Movement studies were complemented with measurements of prey abundance and availability and thermal habitat within home ranges. A thermal choice experiment and energy budget modelling was used to investigate trade-offs between foraging and thermal habitat selection. 3. Male dogfish undertook normal DVM (nocturnal ascent) within relatively small home ranges (-100 x 100 m) comprising along-bottom movements up submarine slopes from deeper, colder waters occupied during the day into warmer, shallow prey-rich areas above the thermocline at night. Few daytime vertical movements occurred. Levels of activity were higher during the night above the thermocline compared to below it during the day indicating they foraged in warm water and rested in colder depths. 4. A thermal choice experiment using environmentally realistic temperatures supported the field observation that dogfish positively avoided warmer water even when it was associated with greater food availability. Males in laboratory aquaria moved into warm water from a cooler refuge only to obtain food, and after food consumption they preferred to rest and digest in cooler water. 5. Modelling of energy budgets under different realistic thermal

TOPEX/El Nino Watch - El Nino Warm Water Pool Decreasing, Jan, 08, 1998

Science.gov (United States)

1998-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Jan. 8, 1998, and sea surface height is an indicator of the heat content of the ocean. The volume of the warm water pool related to the El Nino has decreased by about 40 percent since its maximum in early November, but the area of the warm water pool is still about one and a half times the size of the continental United States. The volume measurements are computed as the sum of all the sea surface height changes as compared to normal ocean conditions. In addition, the maximum water temperature in the eastern tropical Pacific, as measured by the National Oceanic and Atmospheric Administration (NOAA), is still higher than normal. Until these high temperatures diminish, the El Nino warm water pool still has great potential to disrupt global weather because the high water temperatures directly influence the atmosphere. Oceanographers believe the recent decrease in the size of the warm water pool is a normal part of El Nino's natural rhythm. TOPEX/Poseidon has been tracking these fluctuations of the El Nino warm pool since it began in early 1997. These sea surface height measurements have provided scientists with their first detailed view of how El Nino's warm pool behaves because the TOPEX/Poseidon satellite measures the changing sea surface height with unprecedented precision. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level.The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken

Water intake and fish protection sytems for thermal and nuclear power plants

International Nuclear Information System (INIS)

Kuz'min, D.O.; Lukashevich, V.S.

1986-01-01

Various designs of water intake and fish protection systems for TPP and NPP are considered. Water intake systems are divided into shore and outside shore types. There are two main modifications of the latter - opened and closed. The closed systems are more complex for construction and maintenance, but their negative influence on environment is considerably weaker. In disigning of water intake systems basic efforts are directed at optimization of a water intake device disposition, development of reliable repellents for fish, as well as devices for fish catch and return from the water intake region. A special attention is paid to the problem of preventing their icing. The conclusion of expedience of introducing into the water purification system reliable, soft mechanical barriers for fish equipped with means affecting its behaviour and preventing contacts of fish and water intake system elements was drawn

Effectiveness of water release as mitigation for hydroelectric impacts to fish

International Nuclear Information System (INIS)

Lewis, A.F.; Mitchell, A.C.

1995-01-01

Utility companies release water to mitigate the effects of hydroelectric projects on fish habitats. Utility companies, government agencies, and research communities in Canada, the US, Europe, New Zealand, and Australia were surveyed as part of a Canadian Electrical Association study to evaluate the effectiveness of water release as a mitigation. Respondents identified only 28 projects in which water was released specifically to protect fish habitats. Fewer than half of these projects (12) were judged as being effective. Six case histories with preimpact assessment and postimpact monitoring were reviewed. In four cases fish habitat or fish populations or both were maintained; in two cases they were not. The effectiveness of water release differed among rivers and fish species, and was greatest when designed to meet the habitat requirements of each life-history stage. A review of the literature did not support the theory that a particular fraction of the mean annual flow provides the bet fish habitat. Although smaller changes in the flow regime had smaller effects, increasing minimum flows above those historically observed did not necessarily increase fish production

A cascade of warming impacts brings bluefin tuna to Greenland waters

DEFF Research Database (Denmark)

MacKenzie, Brian; Payne, Mark; Boje, Jesper

Rising ocean temperatures are causing marine fish species to shift spatial distributions and ranges, and are altering predator-prey dynamics in food-webs. Most documented cases of species shifts so far involve relatively small species at lower trophic levels, and consider individual species...... since 1985, when temperatures began to rise. The presence of bluefin tuna in this region is likely due to a combination of warm temperatures that are physiologically more tolerable and immigration of an important prey species into the region. We conclude that a cascade of climate change impacts...

Endangered fish species of Kenya's inland waters with emphasis on Labeo spp

OpenAIRE

Kibaara, D.

1986-01-01

The importance of water masses, natural or otherwise, in supporting fisheries, and the importance of fish as human food, cannot be overemphasized. The inland waters of Kenya act as habitats for fish, harbouring many different fish species. It has been observed with interest that certain fish species have decreased in numbers over the years within the inland waters. The decline has been at a rate which, if left unchecked, will eventually cause total di...

Global warming may disproportionately affect larger adults in a predatory coral reef fish

KAUST Repository

Messmer, Vanessa

2016-11-03

Global warming is expected to reduce body sizes of ectothermic animals. Although the underlying mechanisms of size reductions remain poorly understood, effects appear stronger at latitudinal extremes (poles and tropics) and in aquatic rather than terrestrial systems. To shed light on this phenomenon, we examined the size dependence of critical thermal maxima (CTmax) and aerobic metabolism in a commercially important tropical reef fish, the leopard coral grouper (Plectropomus leopardus) following acclimation to current-day (28.5 °C) vs. projected end-of-century (33 °C) summer temperatures for the northern Great Barrier Reef (GBR). CTmax declined from 38.3 to 37.5 °C with increasing body mass in adult fish (0.45-2.82 kg), indicating that larger individuals are more thermally sensitive than smaller conspecifics. This may be explained by a restricted capacity for large fish to increase mass-specific maximum metabolic rate (MMR) at 33 °C compared with 28.5 °C. Indeed, temperature influenced the relationship between metabolism and body mass (0.02-2.38 kg), whereby the scaling exponent for MMR increased from 0.74 ± 0.02 at 28.5 °C to 0.79 ± 0.01 at 33 °C, and the corresponding exponents for standard metabolic rate (SMR) were 0.75 ± 0.04 and 0.80 ± 0.03. The increase in metabolic scaling exponents at higher temperatures suggests that energy budgets may be disproportionately impacted in larger fish and contribute to reduced maximum adult size. Such climate-induced reductions in body size would have important ramifications for fisheries productivity, but are also likely to have knock-on effects for trophodynamics and functioning of ecosystems.

Global warming may disproportionately affect larger adults in a predatory coral reef fish

KAUST Repository

Messmer, Vanessa; Pratchett, Morgan S.; Hoey, Andrew S.; Tobin, Andrew J.; Coker, Darren James; Cooke, Steven J.; Clark, Timothy D.

2016-01-01

Global warming is expected to reduce body sizes of ectothermic animals. Although the underlying mechanisms of size reductions remain poorly understood, effects appear stronger at latitudinal extremes (poles and tropics) and in aquatic rather than terrestrial systems. To shed light on this phenomenon, we examined the size dependence of critical thermal maxima (CTmax) and aerobic metabolism in a commercially important tropical reef fish, the leopard coral grouper (Plectropomus leopardus) following acclimation to current-day (28.5 °C) vs. projected end-of-century (33 °C) summer temperatures for the northern Great Barrier Reef (GBR). CTmax declined from 38.3 to 37.5 °C with increasing body mass in adult fish (0.45-2.82 kg), indicating that larger individuals are more thermally sensitive than smaller conspecifics. This may be explained by a restricted capacity for large fish to increase mass-specific maximum metabolic rate (MMR) at 33 °C compared with 28.5 °C. Indeed, temperature influenced the relationship between metabolism and body mass (0.02-2.38 kg), whereby the scaling exponent for MMR increased from 0.74 ± 0.02 at 28.5 °C to 0.79 ± 0.01 at 33 °C, and the corresponding exponents for standard metabolic rate (SMR) were 0.75 ± 0.04 and 0.80 ± 0.03. The increase in metabolic scaling exponents at higher temperatures suggests that energy budgets may be disproportionately impacted in larger fish and contribute to reduced maximum adult size. Such climate-induced reductions in body size would have important ramifications for fisheries productivity, but are also likely to have knock-on effects for trophodynamics and functioning of ecosystems.

Global warming may disproportionately affect larger adults in a predatory coral reef fish.

Science.gov (United States)

Messmer, Vanessa; Pratchett, Morgan S; Hoey, Andrew S; Tobin, Andrew J; Coker, Darren J; Cooke, Steven J; Clark, Timothy D

2017-06-01

Global warming is expected to reduce body sizes of ectothermic animals. Although the underlying mechanisms of size reductions remain poorly understood, effects appear stronger at latitudinal extremes (poles and tropics) and in aquatic rather than terrestrial systems. To shed light on this phenomenon, we examined the size dependence of critical thermal maxima (CTmax) and aerobic metabolism in a commercially important tropical reef fish, the leopard coral grouper (Plectropomus leopardus) following acclimation to current-day (28.5 °C) vs. projected end-of-century (33 °C) summer temperatures for the northern Great Barrier Reef (GBR). CTmax declined from 38.3 to 37.5 °C with increasing body mass in adult fish (0.45-2.82 kg), indicating that larger individuals are more thermally sensitive than smaller conspecifics. This may be explained by a restricted capacity for large fish to increase mass-specific maximum metabolic rate (MMR) at 33 °C compared with 28.5 °C. Indeed, temperature influenced the relationship between metabolism and body mass (0.02-2.38 kg), whereby the scaling exponent for MMR increased from 0.74 ± 0.02 at 28.5 °C to 0.79 ± 0.01 at 33 °C, and the corresponding exponents for standard metabolic rate (SMR) were 0.75 ± 0.04 and 0.80 ± 0.03. The increase in metabolic scaling exponents at higher temperatures suggests that energy budgets may be disproportionately impacted in larger fish and contribute to reduced maximum adult size. Such climate-induced reductions in body size would have important ramifications for fisheries productivity, but are also likely to have knock-on effects for trophodynamics and functioning of ecosystems. © 2016 John Wiley & Sons Ltd.

Fishing for improvements: managing fishing by boat on New York City water supply reservoirs and lakes

Science.gov (United States)

Nicole L. Green; Jennifer A. Cairo

2008-01-01

In 2003, the New York City Department of Environmental Protection Bureau of Water Supply undertook a 5-year initiative to improve fishing by boat on its water supply reservoirs and controlled lakes in upstate New York. The project includes: revising administrative procedures; cleaning up boat fishing areas on reservoir shores; improving two-way communication with...

Ventimolina stellata gen. et sp. nov. (Haptophyta, Papposphaeraceae) from warm water regions

DEFF Research Database (Denmark)

Thomsen, Helge Abildhauge; Østergaard, Jette B.; Cros, Lluïsa

2015-01-01

It has been known for some time that the distinctive polar weakly calcified coccolithophores are also present in samples from lower latitudes. While polar species may actually have a geographic range that vastly extends beyond the polar realms, it is often the case that the warm water regions...... contribute species that can be allocated to genera previously described based on polar material. We are currently in the process of formally dealing with the warm water species diversity affiliated with the family Papposphaeraceae. In this paper we describe a new genus and species Ventimolina stellata based...

Seahorses under a changing ocean: the impact of warming and acidification on the behaviour and physiology of a poor-swimming bony-armoured fish.

Science.gov (United States)

Faleiro, Filipa; Baptista, Miguel; Santos, Catarina; Aurélio, Maria L; Pimentel, Marta; Pegado, Maria Rita; Paula, José Ricardo; Calado, Ricardo; Repolho, Tiago; Rosa, Rui

2015-01-01

Seahorses are currently facing great challenges in the wild, including habitat degradation and overexploitation, and how they will endure additional stress from rapid climate change has yet to be determined. Unlike most fishes, the poor swimming skills of seahorses, along with the ecological and biological constraints of their unique lifestyle, place great weight on their physiological ability to cope with climate changes. In the present study, we evaluate the effects of ocean warming (+4°C) and acidification (ΔpH = -0.5 units) on the physiological and behavioural ecology of adult temperate seahorses, Hippocampus guttulatus. Adult seahorses were found to be relatively well prepared to face future changes in ocean temperature, but not the combined effect of warming and acidification. Seahorse metabolism increased normally with warming, and behavioural and feeding responses were not significantly affected. However, during hypercapnia the seahorses exhibited signs of lethargy (i.e. reduced activity levels) combined with a reduction of feeding and ventilation rates. Nonetheless, metabolic rates were not significantly affected. Future ocean changes, particularly ocean acidification, may further threaten seahorse conservation, turning these charismatic fishes into important flagship species for global climate change issues.

COMMERCIAL FISH HARVEST IN INLAND WATER BODIES OF GERMANY (A REVIEW

Directory of Open Access Journals (Sweden)

А. Didenko

2016-10-01

Full Text Available Purpose. To analyze scientific and statistical sources on commercial fishery in inland water bodies of Germany. To summarize German experience and identify specific features of this sector. Findings. Commercial fishery in Germany is carried out on 30% (≈250 000 hectares of inland water bodies of Germany. The main fishing regions are prealpine lakes in Bavaria, Lake Constance, lakes in Schleswig-Holstein, Mecklenburg-Western Pomerania federal states as well as lakes and rivers of Brandenburg and Berlin. Commercial fishing on rivers usually has a local importance and is practiced in regions with poorly developed industry. There were 670 commercial fishing organizations in 2014, where 932 people were employed. Each fishing license owner is allowed deploying simultaneously a clearly defined number of fishing gears depending on season. In addition, fishing nets are regulated not only based on their mesh size and length, but also height and the minimum thread diameter. The cardinal difference of German inland fishing is the absence of the periods of total ban on commercial fishing. There are only ban periods for fishing on certain fish species during their spawning seasons. These periods differ for federal states and are listed in the relevant regional fishing rules. The total fish catch in inland waters of Germany by commercial fishermen in 2014 was 3132 tons, much lower than the catches of anglers who caught 18 450 tons at the same year. Most of fish were caught by fishing organizations in the Brandenburg Federal State. Average fish productivity in 2014 was approx. 13 kg/ha (ranging from 10 to 20 kg/ha. Whitefish was the dominant species in catches in the Lake Constance and prealpine lakes of Bavaria, while cyprinids (roach, bream, silver bream, blue bream, etc. dominated in Northern Germany. The profit of commercial fish catch in 2014 was about 12.5 million euros. Among numerous activities aimed at preserving commercial fish populations, Germans

Water Availability in a Warming World

Science.gov (United States)

Aminzade, Jennifer

As climate warms during the 21st century, the resultant changes in water availability are a vital issue for society, perhaps even more important than the magnitude of warming itself. Yet our climate models disagree in their forecasts of water availability, limiting our ability to plan accordingly. This thesis investigates future water availability projections from Coupled Ocean-Atmosphere General Circulation Models (GCMs), primarily using two water availability measures: soil moisture and the Supply Demand Drought Index (SDDI). Chapter One introduces methods of measuring water availability and explores some of the fundamental differences between soil moisture, SDDI and the Palmer Drought Severity Index (PDSI). SDDI and PDSI tend to predict more severe future drought conditions than soil moisture; 21st century projections of SDDI show conditions rivaling North American historic mega-droughts. We compare multiple potential evapotranspiration (EP) methods in New York using input from the GISS Model ER GCM and local station data from Rochester, NY, and find that they compare favorably with local pan evaporation measurements. We calculate SDDI and PDSI values using various EP methods, and show that changes in future projections are largest when using EP methods most sensitive to global warming, not necessarily methods producing EP values with the largest magnitudes. Chapter Two explores the characteristics and biases of the five GCMs and their 20th and 21st century climate projections. We compare atmospheric variables that drive water availability changes globally, zonally, and geographically among models. All models show increases in both dry and wet extremes for SDDI and soil moisture, but increases are largest for extreme drying conditions using SDDI. The percentage of gridboxes that agree on the sign of change of soil moisture and SDDI between models is very low, but does increase in the 21st century. Still, differences between models are smaller than differences

Changes in the fish community and water quality during seven years of stocking piscivorous fish in a shallow lake

DEFF Research Database (Denmark)

Skov, Christian; Perrow, M.R.; Berg, Søren

2002-01-01

evaluated between predatory fish and potential prey and between zooplanktivorous or benthivorous fish and water quality parameters. In addition, potential consumption of piscivorous fishes was calculated. 3. The density of fish feeding on larger zooplankton or benthos (roach >15 cm, crucian carp >15 cm......1. Piscivores (annual stocking of 1000 individuals ha(-1) of 0+ pike and a single stocking of 30 kg ha(-1) of large 20-30 cm perch) were stocked in seven consecutive years in a shallow eutrophic lake in Denmark. The stocking programme aimed at changing food-web structure by reducing...... zooplanktivorous and benthivorous fish, with resultant effects on lower trophic levels and ultimately water quality. 2. The fish community and water quality parameters (Secchi depth, concentrations of total phosphorus, chlorophyll a and suspended solids) were monitored between 1996 and 2000 and relationships were...

TOPEX/El Nino Watch - Warm Water Pool is Increasing, Nov. 10, 1997

Science.gov (United States)

1997-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S./French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Nov. 10, 1997. The volume of extra warm surface water (shown in white) in the core of the El Nino continues to increase, especially in the area between 15 degrees south latitude and 15 degrees north latitude in the eastern Pacific Ocean. The area of low sea level (shown in purple) has decreased somewhat from late October. The white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 centimeters and 32 cm (6 inches to 13 inches) above normal; in the red areas, it is about 10 centimeters (4 inches) above normal. The surface area covered by the warm water mass is about one-and-one-half times the size of the continental United States. The added amount of oceanic warm water near the Americas, with a temperature between 21 to 30 degrees Celsius (70 to 85 degrees Fahrenheit), is about 30 times the volume of water in all the U.S. Great Lakes combined. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level.The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows a large mass of warm water (the red and white areas) that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. The displacement of so much warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world. Using these global data, limited regional measurements from buoys and ships, and a forecasting model of the ocean-atmospheric system, the National Centers for Environmental Prediction (NCEP) of the National Oceanic and Atmospheric

Changing forest water yields in response to climate warming: results from long-term experimental watershed sites across North America

Science.gov (United States)

Creed, Irena F; Spargo, Adam T; Jones, Julia A; Buttle, Jim M; Adams, Mary B; Beall, Fred D; Booth, Eric G; Campbell, John L; Clow, Dave; Elder, Kelly; Green, Mark B; Grimm, Nancy B; Miniat, Chelcy; Ramlal, Patricia; Saha, Amartya; Sebestyen, Stephen; Spittlehouse, Dave; Sterling, Shannon; Williams, Mark W; Winkler, Rita; Yao, Huaxia

2014-01-01

Climate warming is projected to affect forest water yields but the effects are expected to vary. We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm periods. Using the theoretical framework of the Budyko curve, we calculated the effects of climate warming on the annual partitioning of precipitation (P) into evapotranspiration (ET) and water yield. Deviation (d) was defined as a catchment's change in actual ET divided by P [AET/P; evaporative index (EI)] coincident with a shift from a cool to a warm period – a positive d indicates an upward shift in EI and smaller than expected water yields, and a negative d indicates a downward shift in EI and larger than expected water yields. Elasticity was defined as the ratio of interannual variation in potential ET divided by P (PET/P; dryness index) to interannual variation in the EI – high elasticity indicates low d despite large range in drying index (i.e., resilient water yields), low elasticity indicates high d despite small range in drying index (i.e., nonresilient water yields). Although the data needed to fully evaluate ecosystems based on these metrics are limited, we were able to identify some characteristics of response among forest types. Alpine sites showed the greatest sensitivity to climate warming with any warming leading to increased water yields. Conifer forests included catchments with lowest elasticity and stable to larger water yields. Deciduous forests included catchments with intermediate elasticity and stable to smaller water yields. Mixed coniferous/deciduous forests included catchments with highest elasticity and stable water yields. Forest type appeared to influence the resilience of catchment water yields to climate warming, with conifer and deciduous catchments more susceptible to

Arsenic in freshwater fish in the Chihuahua County water reservoirs (Mexico).

Science.gov (United States)

Nevárez, Myrna; Moreno, Myriam Verónica; Sosa, Manuel; Bundschuh, Jochen

2011-01-01

Water reservoirs in Chihuahua County, Mexico, are affected by some punctual and non-punctual geogenic and anthropogenic pollution sources; fish are located at the top of the food chain and are good indicators for the ecosystems pollution. The study goal was to: (i) determine arsenic concentration in fish collected from the Chuviscar, Chihuahua, San Marcos and El Rejon water reservoirs; (ii) to assess if the fishes are suitable for human consumption and (iii) link the arsenic contents in fish with those in sediment and water reported in studies made the same year for these water reservoirs. Sampling was done in summer, fall and winter. The highest arsenic concentration in the species varied through the sampling periods: Channel catfish (Ictalurus punctatus) with 0.22 ± 0.15 mg/kg dw in winter and Green sunfish (Lepomis cyanellus) with 2.00 ± 0.15 mg/kg dw in summer in El Rejon water reservoir. A positive correlation of arsenic contents was found through all sampling seasons in fish samples and the samples of sediment and water. The contribution of the weekly intake of inorganic arsenic, based on the consumption of 0.245 kg fish muscles/body weight/week was found lower than the acceptable weekly intake of 0.015 mg/kg/body weight for inorganic arsenic suggested by FAO/WHO.

Ecosystem responses to warming and watering in typical and desert steppes

OpenAIRE

Zhenzhu Xu; Yanhui Hou; Lihua Zhang; Tao Liu; Guangsheng Zhou

2016-01-01

Global warming is projected to continue, leading to intense fluctuations in precipitation and heat waves and thereby affecting the productivity and the relevant biological processes of grassland ecosystems. Here, we determined the functional responses to warming and altered precipitation in both typical and desert steppes. The results showed that watering markedly increased the aboveground net primary productivity (ANPP) in a typical steppe during a drier year and in a desert steppe over two ...

Ammonia as a respiratory gas in water and air-breathing fishes.

Science.gov (United States)

Randall, David J; Ip, Yuen K

2006-11-01

Ammonia is produced in the liver and excreted as NH(3) by diffusion across the gills. Elevated ammonia results in an increase in gill ventilation, perhaps via stimulation of gill oxygen chemo-receptors. Acidification of the water around the fish by carbon dioxide and acid excretion enhances ammonia excretion and constitutes "environmental ammonia detoxification". Fish have difficulties in excreting ammonia in alkaline water or high concentrations of environmental ammonia, or when out of water. The mudskipper, Periphthalmodon schlosseri, is capable of active NH(4)(+) transport, maintaining low internal levels of ammonia. To prevent a back flux of NH(3), these air-breathing fish can increase gill acid excretion and reduce the membrane NH(3) permeability by modifying the phospholipid and cholesterol compositions of their skin. Several air-breathing fish species can excrete ammonia into air through NH(3) volatilization. Some fish detoxify ammonia to glutamine or urea. The brains of some fish can tolerate much higher levels of ammonia than other animals. Studies of these fish may offer insights into the nature of ammonia toxicity in general.

Community Structure Of Reef Fish In Eastern Luwu Water Territory

Directory of Open Access Journals (Sweden)

Henny Tribuana Cinnawara

2015-01-01

Full Text Available Abstract One bio-indicators the condition of coral reefs is a presence of reef fish. The purpose of research is to determine species composition abundance distribution and structure of reef fish communities in these waters. Data collection was conducted in April at six locations in the north and the south eastern Luwu. Mechanical Underwater Visual Cencus UVC and transect method Line intercept Transec LIT with SCUBA equipment used for research data collection. Total reef fish species collected as many as 366 species belonging to 31 families consisting of 150 species of fish target fish consumption 10 species of indicator fish indicator species 206 types of major fissh. The most dominant indicator type of fish is Chaetodon octofasciatus while the major dominant family Pomacentridae Labridae and Apogonidae. Diversity index values ranged from 2.145 to 3.408. Dominance index C is in the range of 0.056 to 0.298. The result is expected to be a reference literature as basic data for the management of reef fish especially in the waters of eastern Luwu.

Preliminary Evidence for the Amplification of Global Warming in Shallow, Intertidal Estuarine Waters

Science.gov (United States)

Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the warming recorded in the winter and early spring. We hypothesize that this warming may be amplified in the shallow (<2m), nearshore portions ...

Observations of Warm Water in Young Solar-System Analogs

DEFF Research Database (Denmark)

Persson, Magnus Vilhelm

dioxide). The amount of warm water is deduced and its origin is observationally constrained. With both isotopologues observed, the HDO/H2O ratio is deduced. This ratio is then compared to other sources, e.g., comets and the Earth’s ocean, to gain understanding of the origin of the water in our own solar...... system. The emission line fluxes are modeled with radiative transfer tools and compared to other results of water abundances in the same source. The observed water emission, both H18(2 O and HDO is compact for all observed sources and traces the emission on R 150 AU scales or less. In one source...

Seasonality of change: Summer warming rates do not fully represent effects of climate change on lake temperatures

Science.gov (United States)

Winslow, Luke; Read, Jordan S.; Hansen, Gretchen J. A.; Rose, Kevin C.; Robertson, Dale M.

2017-01-01

Responses in lake temperatures to climate warming have primarily been characterized using seasonal metrics of surface-water temperatures such as summertime or stratified period average temperatures. However, climate warming may not affect water temperatures equally across seasons or depths. We analyzed a long-term dataset (1981–2015) of biweekly water temperature data in six temperate lakes in Wisconsin, U.S.A. to understand (1) variability in monthly rates of surface- and deep-water warming, (2) how those rates compared to summertime average trends, and (3) if monthly heterogeneity in water temperature trends can be predicted by heterogeneity in air temperature trends. Monthly surface-water temperature warming rates varied across the open-water season, ranging from 0.013 in August to 0.073°C yr−1 in September (standard deviation [SD]: 0.025°C yr−1). Deep-water trends during summer varied less among months (SD: 0.006°C yr−1), but varied broadly among lakes (–0.056°C yr−1 to 0.035°C yr−1, SD: 0.034°C yr−1). Trends in monthly surface-water temperatures were well correlated with air temperature trends, suggesting monthly air temperature trends, for which data exist at broad scales, may be a proxy for seasonal patterns in surface-water temperature trends during the open water season in lakes similar to those studied here. Seasonally variable warming has broad implications for how ecological processes respond to climate change, because phenological events such as fish spawning and phytoplankton succession respond to specific, seasonal temperature cues.

Effects of deuterium depleted water on reproduction of Rainbow fish

International Nuclear Information System (INIS)

Stefanescu, Ion; Saros-Rogobete, Irina; Titescu, Gheorghe; Caraus, Ion; Pricop, Ferdinand

2001-01-01

The paper refers to an isotopic composition used to prepare fecundating solutions for artificial reproduction of fish. The solution is constituted as a mixture of deuterium depleted water and natural water (whose isotopic concentration is of 85-90 ppm D/(D+H)) in which we can add activating and energizing substances. This fecundating solution ensures an improved fecundating level of fish roe, increase life index in the next growth up stages and increase fish resistance at special medium conditions. (authors)

EPA Office of Water (OW): Fish Consumption Advisories and Fish Tissue Sampling Stations NHDPlus Indexed Datasets

Data.gov (United States)

U.S. Environmental Protection Agency — The Fish Consumption Advisories dataset contains information on Fish Advisory events that have been indexed to the EPA Office of Water NHDPlus v2.1 hydrology and...

Changing forest water yields in response to climate warming: results from long-term experimental watershed sites across North America

Science.gov (United States)

Irena F. Creed; Adam T. Spargo; Julia A. Jones; Jim M. Buttle; Mary B. Adams; Fred D. Beall; Eric G. Booth; John L. Campbell; Dave Clow; Kelly Elder; Mark B. Green; Nancy B. Grimm; Chelcy Miniat; Patricia Ramlal; Amartya Saha; Stephen Sebestyen; Dave Spittlehouse; Shannon Sterling; Mark W. Williams; Rita Winkler; Huaxia. Yao

2014-01-01

Climate warming is projected to affect forest water yields but the effects are expected to vary.We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm...

Examination of water quality changes during transportation of different fish

Directory of Open Access Journals (Sweden)

Istvan Nemeth

2015-12-01

Full Text Available Introduction The growth of population is increasing intensively (7.3 billion people in 2015 and it generates growing importance of fish farming. Primarily, fish meat could provide protein requirements for population so more and more attention must be paid to each sections of farming, for example fish transportation. A badly organized transportation technology can significantly reduce high quality stocks which were produced over several years. Deterioration of transport may occur on each fish distinctly. Bacterial or fungal diseases appear either immediately or days later. During our work, changes in several freshwater (peaceful or predator fish species (of different ages were monitored and analyzed during transport. There were two reasons why we examined the main physical and chemical parameters of the water. On one hand, we were curious to know how much the individuals exposed to heavy loads, which we tried to identify with some stress tests. On the other hand, we would develop a national water carrier monitoring system for the practice. Materials and methods Delivery technologies (foil sack and transport tankers used in practice was applied in the experiment of the study in a real road transport. The physical and chemical data were monitored and checked with the use of multiparameter instruments and photometrial tests. Physiological and stress tests were analyzed from blood plasma of each fish, primarily plasma glucose determination was used. Results After analysis of examined fish species and each ages, it is obvious that either short or long delivery times we choose physical and chemical properties of the transport water would change dramatically, even adequate oxygen balance was ensured. Values of individuals exposed to stress were more significant compared to baseline values. Conclusion We could define concrete changes in key parameters of the transport water with the number of realtime transport implementation which is a good help to

Biogeochemical malfunctioning in sediments beneath a deep-water fish farm.

Science.gov (United States)

Valdemarsen, Thomas; Bannister, Raymond J; Hansen, Pia K; Holmer, Marianne; Ervik, Arne

2012-11-01

We investigated the environmental impact of a deep water fish farm (190 m). Despite deep water and low water currents, sediments underneath the farm were heavily enriched with organic matter, resulting in stimulated biogeochemical cycling. During the first 7 months of the production cycle benthic fluxes were stimulated >29 times for CO(2) and O(2) and >2000 times for NH(4)(+), when compared to the reference site. During the final 11 months, however, benthic fluxes decreased despite increasing sedimentation. Investigations of microbial mineralization revealed that the sediment metabolic capacity was exceeded, which resulted in inhibited microbial mineralization due to negative feed-backs from accumulation of various solutes in pore water. Conclusions are that (1) deep water sediments at 8 °C can metabolize fish farm waste corresponding to 407 and 29 mmol m(-2) d(-1) POC and TN, respectively, and (2) siting fish farms at deep water sites is not a universal solution for reducing benthic impacts. Copyright © 2012 Elsevier Ltd. All rights reserved.

Is Detrusor Contraction during Rapid Bladder Filling Caused by Cold or Warm Water? A Randomized, Controlled, Double-Blind Trial.

Science.gov (United States)

Kozomara, Marko; Mehnert, Ulrich; Seifert, Burkhardt; Kessler, Thomas M

2018-01-01

We investigated whether detrusor contraction during rapid bladder filling is provoked by cold or warm water. Patients with neurogenic lower urinary tract dysfunction were included in this randomized, controlled, double-blind trial. At the end of a standard urodynamic investigation patients underwent 2 bladder fillings using a 4C ice water test or a 36C warm water test saline solution at a filling speed of 100 ml per minute. The order was randomly selected, and patients and investigators were blinded to the order. The primary outcome measure was detrusor overactivity, maximum detrusor pressure and maximum bladder filling volume during the ice and warm water tests. Nine women and 31 men were the subject of data analysis. Neurogenic lower urinary tract dysfunction was caused by spinal cord injury in 33 patients and by another neurological disorder in 7. Irrespective of test order detrusor overactivity occurred significantly more often during the ice water test than during the warm water test (30 of 40 patients or 75% vs 25 of 40 or 63%, p = 0.02). When comparing the ice water test to the warm water test, maximum detrusor pressure was significantly higher and maximum bladder filling volume was significantly lower during the ice water test (each p warm water first) had no effect on the parameters. Our findings imply that the more frequent detrusor overactivity, higher maximum detrusor pressure and lower bladder filling volume during the ice water test compared to the warm water test were caused by cold water. This underlies the theory of a C-fiber mediated bladder cooling reflex in humans. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Partitioning the effects of Global Warming on the Hydrological Cycle with Stable Isotopes in Water Vapor

Science.gov (United States)

Dee, S. G.; Russell, J. M.; Nusbaumer, J. M.; Konecky, B. L.; Buenning, N. H.; Lee, J. E.; Noone, D.

2016-12-01

General circulation models (GCMs) suggest that much of the global hydrological cycle's response to anthropogenic warming will be caused by increased lower-tropospheric water vapor concentrations and associated feedbacks. However, fingerprinting changes in the global hydrological cycle due to anthropogenic warming remains challenging. Held and Soden (2006) predicted that as lower-tropospheric water vapor increases, atmospheric circulation will weaken as climate warms to maintain the surface energy budget. Unfortunately, the strength of this feedback and the fallout for other branches of the hydrological cycle is difficult to constrain in situ or with GCMs alone. We demonstrate the utility of stable hydrogen isotope ratios in atmospheric water vapor to quantitatively trace changes in atmospheric circulation and convective mass flux in a warming world. We compare water isotope-enabled GCM experiments for control (present-day) CO2 vs. high CO2(2x, 4x) atmospheres in two GCMs, IsoGSM and iCAM5. We evaluate changes in the distribution of water vapor, vertical velocity (omega), and the stream function between these experiments in order to identify spatial patterns of circulation change over the tropical Pacific (where vertical motion is strong) and map the δD of water vapor associated with atmospheric warming. We also probe the simulations to isolate isotopic signatures associated with water vapor residence time, precipitation efficiency, divergence, and cloud physics. We show that there are robust mechanisms that moisten the troposphere and weaken convective mass flux, and that these mechanisms can be tracked using the δD of water vapor. Further, we find that these responses are most pronounced in the upper troposphere. These findings provide a framework to develop new metrics for the detection of global warming impacts to the hydrological cycle. Further, currently available satellite missions measure δD in the atmospheric boundary layer, the free atmosphere, or the

Water runoff vs modern climatic warming in mountainous cryolithic zone in North-East Russia

Science.gov (United States)

Glotov, V. E.; Glotova, L. P.

2018-01-01

The article presents the results of studying the effects of current climatic warming for both surface and subsurface water runoffs in North-East Russia, where the Main Watershed of the Earth separates it into the Arctic and Pacific continental slopes. The process of climatic warming is testified by continuous weather records during 80-100 years and longer periods. Over the Arctic slope and in the northern areas of the Pacific slope, climatic warming results in a decline in a total runoff of rivers whereas the ground-water recharge becomes greater in winter low-level conditions. In the southern Pacific slope and in the Sea of Okhotsk basin, the effect of climatic warming is an overall increase in total runoff including its subsurface constituents. We believe these peculiar characters of river runoff there to be related to the cryolithic zone environments. Over the Arctic slope and the northern Pacific slope, where cryolithic zone is continuous, the total runoff has its subsurface constituent as basically resulting from discharge of ground waters hosted in seasonally thawing rocks. Warmer climatic conditions favor growth of vegetation that needs more water for the processes of evapotranspiration and evaporation from rocky surfaces in summer seasons. In the Sea of Okhotsk basin, where the cryolithic zone is discontinuous, not only ground waters in seasonally thawing layers, but also continuous taliks and subpermafrost waters participate in processes of river recharges. As a result, a greater biological productivity of vegetation cover does not have any effect on ground-water supply and river recharge processes. If a steady climate warming is provided, a continuous cryolithic zone can presumably degrade into a discontinuous and then into an island-type permafrost layer. Under such a scenario, there will be a general increase in the total runoff and its subsurface constituent. From geoecological viewpoints, a greater runoff will have quite positive effects, whereas some

Survival of cool and warm freshwater fish following chloramine-T exposure

Science.gov (United States)

Gaikowski, M.P.; Larson, W.J.; Gingerich, W.H.

2008-01-01

Chloramine-T is presently available in the USA to control mortalities associated with bacterial gill disease or external columnaris only through an Investigational New Animal Drug Permit authorized by the US Food and Drug Administration (FDA). Its US approval hinges on FDA's acceptance of several key data, including those describing animal safety. Chloramine-T is presently applied in US aquaculture, by permit only, once daily on consecutive or alternate days for 1??h at 10 to 20??mg/L to control mortalities associated with bacterial gill disease or external columnaris. Our objective was to determine the safety of chloramine-T bath exposures at multiples of the proposed maximum treatment concentration (i.e., 0, 20, 60, 100, and 200??mg/L) administered on four consecutive days at 20????C to lake sturgeon Acipenser fulvescens, northern pike Esox lucius, and walleye Sander vitreum, or at 27????C to channel catfish Ictalurus punctatus, and largemouth bass Micropterus salmoides. All fish were tested as five to eight week old fry except for walleye and channel catfish which were tested as both fry and fingerling (fingerlings were at least four weeks older than the fry tested). Walleye and channel catfish were selected to evaluate the effects of life stage (fry vs. fingerling), temperature (walleye - 15, 20, or 25????C; channel catfish - 22, 27, or 32????C), exposure duration (60 vs. 180??min), and water chemistry (walleye only - reconstituted soft water vs. well water). Except for channel catfish fry, survival was significantly reduced only when fish were treated at 100 or 200??mg/L. Channel catfish fry survival was significantly reduced when exposed at 60??mg/L for 180??min at 27????C. Based on our mortality data, chloramine-T administered once daily for 60??min on four consecutive days at concentrations of up to 20??mg/L is not likely to adversely affect survival of cool or warmwater fish cultured in freshwater. Crown Copyright ?? 2007.

Optimizing fish and stream-water mercury metrics for calculation of fish bioaccumulation factors

Science.gov (United States)

Paul Bradley; Karen Riva Murray; Barbara C. Scudder Elkenberry; Christopher D. Knightes; Celeste A. Journey; Mark A. Brigham

2016-01-01

Mercury (Hg) bioaccumulation factors (BAFs; ratios of Hg in fish [Hgfish] and water[Hgwater]) are used to develop Total Maximum Daily Load and water quality criteria for Hg-impaired waters. Protection of wildlife and human health depends directly on the accuracy of site-specific estimates of Hgfish and Hgwater and the predictability of the relation between these...

An integrated fish-plankton aquaculture system in brackish water.

Science.gov (United States)

Gilles, S; Fargier, L; Lazzaro, X; Baras, E; De Wilde, N; Drakidès, C; Amiel, C; Rispal, B; Blancheton, J-P

2013-02-01

Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous fish and phytoplankton. The fish recycle nutrients by consuming live (and dead) algae and provide the inorganic carbon to fuel the growth of live algae. In the meanwhile, algae purify the water and generate the oxygen required by fishes. Such mechanism stabilizes the functioning of an artificially recycling ecosystem, as exemplified by combining the euryhaline tilapia Sarotherodon melanotheron heudelotii and the unicellular alga Chlorella sp. Feed addition in this ecosystem results in faster fish growth but also in an increase in phytoplankton biomass, which must be limited. In the prototype described here, the algal population control is exerted by herbivorous zooplankton growing in a separate pond connected in parallel to the fish-algae ecosystem. The zooplankton production is then consumed by tilapia, particularly by the fry and juveniles, when water is returned to the main circuit. Chlorella sp. and Brachionus plicatilis are two planktonic species that have spontaneously colonized the brackish water of the prototype, which was set-up in Senegal along the Atlantic Ocean shoreline. In our system, water was entirely recycled and only evaporation was compensated (1.5% volume/day). Sediment, which accumulated in the zooplankton pond, was the only trophic cul-de-sac. The system was temporarily destabilized following an accidental rotifer invasion in the main circuit. This caused Chlorella disappearance and replacement by opportunist algae, not consumed by Brachionus. Following the entire consumption of the Brachionus population by tilapias, Chlorella predominated again. Our artificial ecosystem combining S. m. heudelotii, Chlorella and B. plicatilis thus appeared to be resilient. This farming system was operated over one year with a fish productivity of 1.85 kg/m2 per year during the cold season (January to April).

FISH PHYSIOLOGY, TOXICOLOGY, AND WATER QUALITY:

Science.gov (United States)

Twenty-one participants from Europe, North America and China convened in Chongqing, China, October 12-14, 2005, for the Eighth International Symposium in Fish Physiology, Toxicology and Water Quality. The subject of the meeting was "Hypoxia in vertebrates: Comparisons of terrestr...

Energy storage and fecundity explain deviations from ecological stoichiometry predictions under global warming and size-selective predation.

Science.gov (United States)

Zhang, Chao; Jansen, Mieke; De Meester, Luc; Stoks, Robby

2016-11-01

A key challenge for ecologists is to predict how single and joint effects of global warming and predation risk translate from the individual level up to ecosystem functions. Recently, stoichiometric theory linked these levels through changes in body stoichiometry, predicting that both higher temperatures and predation risk induce shifts in energy storage (increases in C-rich carbohydrates and reductions in N-rich proteins) and body stoichiometry (increases in C : N and C : P). This promising theory, however, is rarely tested and assumes that prey will divert energy away from reproduction under predation risk, while under size-selective predation, prey instead increase fecundity. We exposed the water flea Daphnia magna to 4 °C warming and fish predation risk to test whether C-rich carbohydrates increase and N-rich proteins decrease, and as a result, C : N and C : P increase under warming and predation risk. Unexpectedly, warming decreased body C : N, which was driven by reductions in C-rich fat and sugar contents while the protein content did not change. This reflected a trade-off where the accelerated intrinsic growth rate under warming occurred at the cost of a reduced energy storage. Warming reduced C : N less and only increased C : P and N : P in the fish-period Daphnia. These evolved stoichiometric responses to warming were largely driven by stronger warming-induced reductions in P than in C and N and could be explained by the better ability to deal with warming in the fish-period Daphnia. In contrast to theory predictions, body C : N decreased under predation risk due to a strong increase in the N-rich protein content that offsets the increase in C-rich fat content. The higher investment in fecundity (more N-rich eggs) under predation risk contributed to this stronger increase in protein content. Similarly, the lower body C : N of pre-fish Daphnia also matched their higher fecundity. Warming and predation risk independently shaped body

n3- polyunsaturated Fat Acid Content of Some Edible Fish from Bahrain Waters

Science.gov (United States)

Al-Arrayedu, F. H.; Al Maskati, H. A.; Abdullah, F. J.

1999-08-01

This study was performed to determine the content of n3- polyunsaturated fatty acids in 10 fish species that are commonly consumed in Bahrain in addition to the main commercial shrimp species. White sardinella, which is a plankton feeder, had the highest content of n3- polyunsaturated fatty acids. It had the highest value of eicosapentaenoic acid (146.5 ± 20 mg 100 g-1) and linolenic acid (98.9±f 100 g-1) and the second highest value of docosahexaenoic acid at (133.7 ± 22 mg 100 g-1). Spanish mackerel which feeds mainly on sardinella was second with eicosapentaenoc acid at 55 ± 5.4 mg 100 g-1, docosahexaenoic acid at 161 ± 19.8 mg 100 g-1, linolenic acid at 16.4 mg 100 g-1 and docosapentaenoic acid at 25 ± 1.9 mg 100 g-1. Rabbitfish, the most popular edible fish in Bahrain which feeds mainly on benthic algae had the third highest content of n3- polyunsaturated fatty acids with eicosapentaenoic acid at 37.5 ± 3.9 mg 100 g-1, docosahexaenoic acid at 76 ± 6.7 mg 100 g-1, and docosapentaenoic acid at 85.8 ± 10 mg 100 g-1. The other fish and crustacean species studied were Arabian carpet shark, doublebar bream, grouper, gray grunt, golden travally, keeled mullet, spangled emperor and shrimp. The study explores the transfer of n3- polyunsaturated fatty acids through the food webs of the examined fish. It is apparent, generally, that plankton feeders displayed the highest content of n3- polyunsaturated fatty acids followed by seaweed and algae grazers, with benthic carnivores feeding on invertebrates displaying the poorest content. The values reported here, however, are much lower than those reported for fish available in American markets and in Mediterranean fish. Warm water temperature and high salinity which lead to lowering of the density of phytoplankton and phytoplankton content of n3- polyunsaturated fatty acids are suggested as the reason for the observed low values of n3- polyunsaturated fatty acids in Bahrain fish.

The major and trace element chemistry of fish and lake water within ...

African Journals Online (AJOL)

Chemical elements in lake water are incorporated into fish tissues through bioconcentration and biomagnification. Lake water and fish tissue samples from 23 lakes, located within 4 major South African catchments, were analysed to investigate the link between element concentrations in lake water and otolith, fin spine, ...

Calcium and Strontium in Swedish Waters and Fish, and Accumulation of Strontium-90

Energy Technology Data Exchange (ETDEWEB)

Agnedal, P O

1966-04-15

The purpose of this study has been to investigate the correlation between calcium and strontium in fish in relation to the concentration of these elements in the water. An investigation of the uptake of strontium-90 has also been made and permissible levels of strontium-90 in the water is calculated based upon the uptake in fish muscle tissues. Lakes with calcium concentrations between 2 - 63 mg/l have been studied and samples from the Baltic coastal water are also included. Three fish species are studied, viz. pike (Esox lucius (L.)), perch (Perca fluviatilis (L.)) and roach (Leuciscus rutilus (L.)). Bones, muscle tissues and skin + scales have been analysed. Strontium-90 measurements have been made showing an increase in both water and fish. Calculations show that in water with about 2 mg Ca/l a 10-fold increase of the existing strontium-90 level might give strontium-90 concentrations in fish muscle tissues close to what is permissible. In lakes with calcium concentrations 20 - 40 mg/l the permissible levels for drinking water will be exceeded before the fish consumption would have to be restricted.

Calcium and Strontium in Swedish Waters and Fish, and Accumulation of Strontium-90

International Nuclear Information System (INIS)

Agnedal, P.O.

1966-04-01

The purpose of this study has been to investigate the correlation between calcium and strontium in fish in relation to the concentration of these elements in the water. An investigation of the uptake of strontium-90 has also been made and permissible levels of strontium-90 in the water is calculated based upon the uptake in fish muscle tissues. Lakes with calcium concentrations between 2 - 63 mg/l have been studied and samples from the Baltic coastal water are also included. Three fish species are studied, viz. pike (Esox lucius (L.)), perch (Perca fluviatilis (L.)) and roach (Leuciscus rutilus (L.)). Bones, muscle tissues and skin + scales have been analysed. Strontium-90 measurements have been made showing an increase in both water and fish. Calculations show that in water with about 2 mg Ca/l a 10-fold increase of the existing strontium-90 level might give strontium-90 concentrations in fish muscle tissues close to what is permissible. In lakes with calcium concentrations 20 - 40 mg/l the permissible levels for drinking water will be exceeded before the fish consumption would have to be restricted

Comparing demersal fish assemblage between periods of contrasting climate and fishing pressure

NARCIS (Netherlands)

Hofstede, ter R.; Rijnsdorp, A.D.

2011-01-01

Fish communities are dynamic and their structure is known to change over time. Traditionally, these changes were considered to be fisheries-induced, but recent analyses also suggest that global warming could affect the distribution, abundance, and assemblage composition of marine fish. However,

Influence of inlet water on the biotic and abiotic variables in a fish pond

Directory of Open Access Journals (Sweden)

L. H. Sipaúba-Tavares

Full Text Available Abstract The effects of treated and untreated water inlets with macrophytes on the improvement of water quality and zooplankton community were evaluated in a fish pond with continuous water flow. Water and zooplankton samples were retrieved at four sites during nine months. There were differences (p<0.01 between inlet water from fish pond and inlet water from canal with macrophytes, featuring higher concentrations of nutrient load, mainly TAN and TP in the former. The inlet water from fish pond contained a higher number of abundant species (9 species, whilst the water supply from the canal with macrophytes had a greater richness (31 species of zooplankton species. Results showed that inlet water without macrophytes directly affected the characteristics of the water column and the dominance of zooplankton species such as Thermocyclops decipiens, and greater abundance of Rotifera species. Since aquatic plants in the inlet water of fish pond analyzed showed lower allochthonous material loads from the previous fish pond, the management adopted with macrophytes may be applied to avoid eutrophication risks, common in farm ponds.

Pathways of warm water to the Northeast Greenland outlet glaciers

Science.gov (United States)

Schaffer, Janin; Timmermann, Ralph; Kanzow, Torsten; Arndt, Jan Erik; Mayer, Christoph; Schauer, Ursula

2015-04-01

The ocean plays an important role in modulating the mass balance of the Greenland Ice Sheet by delivering heat to the marine-terminating outlet glaciers surrounding the Greenland coast. The warming and accumulation of Atlantic Water in the subpolar North Atlantic has been suggested to be a potential driver of the glaciers' retreat over the last decades. The shelf regions thus play a critical role for the transport of Atlantic Water towards the glaciers, but also for the transfer of freshwater towards the deep ocean. A key region for the mass balance of the Greenland Ice Sheet is the Northeast Greenland Ice Stream. This large ice stream drains the second-largest basin of the Greenland Ice Sheet and feeds three outlet glaciers. The largest one is Nioghalvfjerdsfjorden (79°N-Glacier) featuring an 80 km long floating ice tongue. Both the ocean circulation on the continental shelf off Northeast Greenland and the circulation in the cavity below the ice tongue are weakly constrained so far. In order to study the relevant processes of glacier-ocean interaction we combine observations and model work. Here we focus on historic and recent hydrographic observations and on the complex bathymetry in the Northeast Greenland shelf region, which is thought to steer the flux of warm Atlantic water onto the continental shelf and into the sub-ice cavity beneath the 79°N-Glacier. We present a new global topography data set, RTopo-2, which includes the most recent surveys on the Northeast Greenland continental shelf and provides a detailed bathymetry for all around Greenland. In addition, RTopo-2 contains ice and bedrock surface topographies for Greenland and Antarctica. Based on the updated ocean bathymetry and a variety of hydrographic observations we show the water mass distribution on the continental shelf off Northeast Greenland. These maps enable us to discuss possible supply pathways of warm modified Atlantic waters on the continental shelf and thus potential ways of heat

Understanding the causes of recent warming of mediterranean waters. How much could be attributed to climate change?

Science.gov (United States)

Macias, Diego; Garcia-Gorriz, Elisa; Stips, Adolf

2013-01-01

During the past two decades, Mediterranean waters have been warming at a rather high rate resulting in scientific and social concern. This warming trend is observed in satellite data, field data and model simulations, and affects both surface and deep waters throughout the Mediterranean basin. However, the warming rate is regionally different and seems to change with time, which has led to the question of what causes underlie the observed trends. Here, we analyze available satellite information on sea surface temperature (SST) from the last 25 years using spectral techniques and find that more than half of the warming tendency during this period is due to a non-linear, wave-like tendency. Using a state of the art hydrodynamic model, we perform a hindcast simulation and obtain the simulated SST evolution of the Mediterranean basin for the last 52 years. These SST results show a clear sinusoidal tendency that follows the Atlantic Multidecadal Oscillation (AMO) during the simulation period. Our results reveal that 58% of recent warming in Mediterranean waters could be attributed to this AMO-like oscillation, being anthropogenic-induced climate change only responsible for 42% of total trend. The observed acceleration of water warming during the 1990s therefore appears to be caused by a superimposition of anthropogenic-induced warming with the positive phase of the AMO, while the recent slowdown of this tendency is likely due to a shift in the AMO phase. It has been proposed that this change in the AMO phase will mask the effect of global warming in the forthcoming decades, and our results indicate that the same could also be applicable to the Mediterranean Sea. Henceforth, natural multidecadal temperature oscillations should be taken into account to avoid underestimation of the anthropogenic-induced warming of the Mediterranean basin in the future.

Understanding the causes of recent warming of mediterranean waters. How much could be attributed to climate change?

Directory of Open Access Journals (Sweden)

Diego Macias

Full Text Available During the past two decades, Mediterranean waters have been warming at a rather high rate resulting in scientific and social concern. This warming trend is observed in satellite data, field data and model simulations, and affects both surface and deep waters throughout the Mediterranean basin. However, the warming rate is regionally different and seems to change with time, which has led to the question of what causes underlie the observed trends. Here, we analyze available satellite information on sea surface temperature (SST from the last 25 years using spectral techniques and find that more than half of the warming tendency during this period is due to a non-linear, wave-like tendency. Using a state of the art hydrodynamic model, we perform a hindcast simulation and obtain the simulated SST evolution of the Mediterranean basin for the last 52 years. These SST results show a clear sinusoidal tendency that follows the Atlantic Multidecadal Oscillation (AMO during the simulation period. Our results reveal that 58% of recent warming in Mediterranean waters could be attributed to this AMO-like oscillation, being anthropogenic-induced climate change only responsible for 42% of total trend. The observed acceleration of water warming during the 1990s therefore appears to be caused by a superimposition of anthropogenic-induced warming with the positive phase of the AMO, while the recent slowdown of this tendency is likely due to a shift in the AMO phase. It has been proposed that this change in the AMO phase will mask the effect of global warming in the forthcoming decades, and our results indicate that the same could also be applicable to the Mediterranean Sea. Henceforth, natural multidecadal temperature oscillations should be taken into account to avoid underestimation of the anthropogenic-induced warming of the Mediterranean basin in the future.

Historical change in fish species distribution: shifting reference conditions and global warming effects.

Science.gov (United States)

Pont, Didier; Logez, M; Carrel, G; Rogers, C; Haidvogl, G

Species distributions models (SDM) that rely on estimated relationships between present environmental conditions and species presence-absence are widely used to forecast changes of species distributions caused by global warming but far less to reconstruct historical assemblages. By compiling historical fish data from the turn to the middle of the twentieth century in a similar way for several European catchments (Rhône, Danube), and using already published SDMs based on current observations, we: (1) tested the predictive accuracy of such models for past climatic conditions, (2) compared observed and expected cumulated historical species occurrences at sub-catchment level, and (3) compared the annual variability in the predictions within one sub-catchment (Salzach) under a future climate scenario to the long-term variability of occurrences reconstructed during an extended historical period (1800-2000). We finally discuss the potential of these SDMs to define a "reference condition", the possibility of a shift in baseline condition in relation with anthropogenic pressures, and past and future climate variability. The results of this study clearly highlight the potential of SDM to reconstruct the past composition of European fish assemblages and to analyze the historical ecological status of European rivers. Assessing the uncertainty associated with species distribution projections is of primary importance before evaluating and comparing the past and future distribution of species within a given catchment.

Flying fish accelerate at 5 G to leap from the water surface

Science.gov (United States)

Yang, Patricia; Phonekeo, Sulisay; Xu, Ke; Chang, Shui-Kai; Hu, David

2013-11-01

Flying fish can both swim underwater and glide in air. Transitioning from swimming to gliding requires penetration of the air-water interface, or breaking the ``surface tension barrier,'' a formidable task for juvenile flying fish measuring 1 to 5 cm in length. In this experimental investigation, we use high-speed videography to characterize the kinematics of juvenile flying fish as they leap from the water surface. During this process, which lasts 0.05 seconds, flying fish achieve body accelerations of 5 times earth's gravity and gliding speeds of 1.3 m/s, an order of magnitude higher than their steady swimming speed. We rationalize this anomalously high speed on the basis of the hydrodynamic and surface tension forces and torques experienced by the fish. Specifically, leaping fish experience skin friction forces only on the submerged part of their body, permitting them to achieve much higher speeds than in steady underwater swimming. We also perform experiments using a towed flying fish mimc to determine optimality of various parameters in this process, including body angle and start position with respect to the water surface.

Tributyltin distribution and producing androgenic activity in water, sediment, and fish muscle.

Science.gov (United States)

Shue, Meei-Fang; Chen, Ting-Chien; Bellotindos, Luzvisminda M; Lu, Ming-Chun

2014-01-01

This study investigated the concentrations of Tributyltin (TBT) in water, sediment, and fish muscle samples taken from Kaohsiung Harbor and Kaoping River estuary, Taiwan. TBT concentrations in water and sediment samples ranged from less than 18.5 to 34.1 ng Sn L(-1) and from 2.44 to 29.7 ng Sn g(-1) weight per weight (w/w), respectively. Concentrations in the TBT-contaminated fish muscle samples ranged from 10.8 to 79.6 ng Sn g(-1) w/w. The TBT concentrations in fish muscle were higher than those in water and sediment samples. The fish muscle/water TBT bioconcentration factor (BCF) ranged from 590 to 3363 L kg(-1). Additionally, the water samples were assessed for androgenic activity with an MCF7-AR1 human breast cancer cell line. The androgenic activity ranged from 0.94 to 3.1 ng-dihydrotestosterone per litre water (ng-DHT L(-1)). Higher concentrations of TBT in water and sediment samples occurred in the dry season, but the androgenic activity had higher values in the rainy season.

Increasing water cycle extremes in California and in relation to ENSO cycle under global warming

Science.gov (United States)

Yoon, Jin-Ho; Wang, S-Y Simon; Gillies, Robert R.; Kravitz, Ben; Hipps, Lawrence; Rasch, Philip J.

2015-01-01

Since the winter of 2013–2014, California has experienced its most severe drought in recorded history, causing statewide water stress, severe economic loss and an extraordinary increase in wildfires. Identifying the effects of global warming on regional water cycle extremes, such as the ongoing drought in California, remains a challenge. Here we analyse large-ensemble and multi-model simulations that project the future of water cycle extremes in California as well as to understand those associations that pertain to changing climate oscillations under global warming. Both intense drought and excessive flooding are projected to increase by at least 50% towards the end of the twenty-first century; this projected increase in water cycle extremes is associated with a strengthened relation to El Niño and the Southern Oscillation (ENSO)—in particular, extreme El Niño and La Niña events that modulate California's climate not only through its warm and cold phases but also its precursor patterns. PMID:26487088

Water guns affect abundance and behavior of bigheaded carp and native fish differently

Science.gov (United States)

Rivera, Jose; Glover, David C.; Kocovsky, Patrick; Garvey, James E.; Gaikowski, Mark; Jensen, Nathan R.; Adams, Ryan F.

2017-01-01

Water guns have shown the potential to repel nuisance aquatic organisms. This study examines the effects of exposure to a 1966.4 cm3 seismic water gun array (two guns) on the abundance and behavior of Bighead Carp Hypophthalmichthys nobilis, Silver Carp H. molitrix (collectively referred to as bigheaded carp) and native fishes (e.g., Smallmouth Buffalo Ictiobus bubalus). Water guns were deployed in a channel that connects the Illinois River to backwater quarry pits that contained a large transient population of bigheaded carp. To evaluate the effect of water guns, mobile side-looking split-beam hydroacoustic surveys were conducted before, during and between replicated water gun firing periods. Water guns did not affect abundance of bigheaded carp, but abundance of native fish detected during the firing treatment was 43 and 34% lower than the control and water guns off treatments, respectively. The proximity of bigheaded carp to the water gun array was similar between the water guns on and water guns off treatments. In contrast, the closest detected native fish were detected farther from the water guns during the water guns on treatment (mean ± SE, 32.38 ± 3.32 m) than during the water guns off treatment (15.04 ± 1.59 m). The water gun array had a greater impact on native fish species than on bigheaded carp. Caution should be taken to the extrapolation of these results to other fish species and to fish exposed to water guns in different environments (e.g., reduced shoreline interaction) or exposure to a larger array of water guns, or for use of water guns for purposes other than a barrier.

Water guns affect abundance and behavior of bigheaded carp and native fish differently

Science.gov (United States)

Rivera, Jose; Glover, David C.; Kocovsky, Patrick; Garvey, James E.; Gaikowski, Mark; Jensen, Nathan R.; Adams, Ryan F.

2018-01-01

Water guns have shown the potential to repel nuisance aquatic organisms. This study examines the effects of exposure to a 1966.4 cm3 seismic water gun array (two guns) on the abundance and behavior of Bighead Carp Hypophthalmichthys nobilis, Silver Carp H. molitrix (collectively referred to as bigheaded carp) and native fishes (e.g., Smallmouth Buffalo Ictiobus bubalus). Water guns were deployed in a channel that connects the Illinois River to backwater quarry pits that contained a large transient population of bigheaded carp. To evaluate the effect of water guns, mobile side-looking split-beam hydroacoustic surveys were conducted before, during and between replicated water gun firing periods. Water guns did not affect abundance of bigheaded carp, but abundance of native fish detected during the firing treatment was 43 and 34% lower than the control and water guns off treatments, respectively. The proximity of bigheaded carp to the water gun array was similar between the water guns on and water guns off treatments. In contrast, the closest detected native fish were detected farther from the water guns during the water guns on treatment (mean ± SE, 32.38 ± 3.32 m) than during the water guns off treatment (15.04 ± 1.59 m). The water gun array had a greater impact on native fish species than on bigheaded carp. Caution should be taken to the extrapolation of these results to other fish species and to fish exposed to water guns in different environments (e.g., reduced shoreline interaction) or exposure to a larger array of water guns, or for use of water guns for purposes other than a barrier.

FISH PHYSIOLOGY, TOXICOLOGY, AND WATER QUALITY

Science.gov (United States)

Scientists from ten countries presented papers at the Fifth International Symposium on Fish Physiology, Toxicology, and Water Quality, which was held on the campus of the city University of Hong Kong on November 10-13, 1998. These Proceedings include 23 papers presented in sessi...

Methodology for predicting cooling water effects on fish

International Nuclear Information System (INIS)

Cakiroglu, C.; Yurteri, C.

1998-01-01

The mathematical model presented here predicts the long-term effects of once-through cooling water systems on local fish populations. The fish life cycle model simulates different life stages of fish by using appropriate expressions representing growth and mortality rates. The heart of the developed modeling approach is the prediction of plant-caused reduction in total fish population by estimating recruitment to adult population with and without entrainment of ichthyoplankton and impingement of small fish. The model was applied to a local fish species, gilthead (Aparus aurata), for the case of a proposed power plant in the Aegean region of Turkey. The simulations indicate that entrainment and impingement may lead to a population reduction of about 2% to 8% in the long run. In many cases, an impact of this size can be considered rather unimportant. In the case of sensitive and ecologically values species facing extinction, however, necessary precautions should be taken to minimize or totally avoid such an impact

Okanogan Subbasin Water Quality and Quantity Report for Anadromous Fish in 2006.

Energy Technology Data Exchange (ETDEWEB)

Colville Tribes, Department of Fish & Wildlife

2007-12-01

Fish need water of sufficient quality and quantity in order to survive and reproduce. The list of primary water quality indicators appropriate for monitoring of anadromous fish, as identified by the Upper Columbia Monitoring Strategy, includes: discharge, temperature, dissolved oxygen, pH, turbidity, conductivity, nitrogen, phosphorus and ammonia. The Colville Tribes Fish and Wildlife Department began evaluating these water quality indicators in 2005 and this report represents data collected from October 1, 2005 through September 30, 2006. We collected empirical status and trend data from various sources to evaluate each water quality indicator along the main stem Okanogan and Similkameen Rivers along with several tributary streams. Each water quality indicator was evaluated based upon potential impacts to salmonid survival or productivity. Specific conductance levels and all nutrient indicators remained at levels acceptable for growth, survival, and reproduction of salmon and steelhead. These indicators were also considered of marginal value for monitoring environmental conditions related to salmonids within the Okanogan subbasin. However, discharge, temperature, turbidity, dissolved oxygen and pH in that order represent the water quality indicators that are most useful for monitoring watershed health and habitat changes and will help to evaluate threats or changes related to salmon and steelhead restoration and recovery. On the Okanogan River minimum flows have decreased over the last 12 years at a rate of -28.3CFS/year as measured near the town of Malott, WA. This trend is not beneficial for salmonid production and efforts to reverse this trend should be strongly encouraged. Turbidity levels in Bonaparte and Omak Creek were a concern because they had the highest monthly average readings. Major upland disturbance in the Bonaparte Creek watershed has occurred for decades and agricultural practices within the riparian areas along this creek have lead to major

Assessing water quality of the Chesapeake Bay by the impact of sea level rise and warming

Science.gov (United States)

Wang, P.; Linker, L.; Wang, H.; Bhatt, G.; Yactayo, G.; Hinson, K.; Tian, R.

2017-08-01

The influence of sea level rise and warming on circulation and water quality of the Chesapeake Bay under projected climate conditions in 2050 were estimated by computer simulation. Four estuarine circulation scenarios in the estuary were run using the same watershed load in 1991-2000 period. They are, 1) the Base Scenario, which represents the current climate condition, 2) a Sea Level Rise Scenario, 3) a Warming Scenario, and 4) a combined Sea Level Rise and Warming Scenario. With a 1.6-1.9°C increase in monthly air temperatures in the Warming Scenario, water temperature in the Bay is estimated to increase by 0.8-1°C. Summer average anoxic volume is estimated to increase 1.4 percent compared to the Base Scenario, because of an increase in algal blooms in the spring and summer, promotion of oxygen consumptive processes, and an increase of stratification. However, a 0.5-meter Sea Level Rise Scenario results in a 12 percent reduction of anoxic volume. This is mainly due to increased estuarine circulation that promotes oxygen-rich sea water intrusion in lower layers. The combined Sea Level Rise and Warming Scenario results in a 10.8 percent reduction of anoxic volume. Global warming increases precipitation and consequently increases nutrient loads from the watershed by approximately 5-7 percent. A scenario that used a 10 percent increase in watershed loads and current estuarine circulation patterns yielded a 19 percent increase in summer anoxic volume, while a scenario that used a 10 percent increase in watershed loads and modified estuarine circulation patterns by the aforementioned sea level rise and warming yielded a 6 percent increase in summer anoxic volume. Impacts on phytoplankton, sediments, and water clarity were also analysed.

Proposal of computation chart for general use for diffusion prediction of discharged warm water

International Nuclear Information System (INIS)

Wada, Akira; Kadoyu, Masatake

1976-01-01

The authors have developed the unique simulation analysis method using the numerical models for the prediction of discharged warm water diffusion. At the present stage, the method is adopted for the precise analysis computation in order to make the prediction of the diffusion of discharged warm water at each survey point, but instead of this method, it is strongly requested that some simple and easy prediction methods should be established. For the purpose of meeting this demand, in this report, the computation chart for general use is given to predict simply the diffusion range of discharged warm water, after classifying the semi-infinite sea region into several flow patterns according to the sea conditions and conducting the systematic simulation analysis with the numerical model of each pattern, respectively. (1) Establishment of the computation conditions: The special sea region was picked up as the area to be investigated, which is semi-infinite facing the outer sea and along the rectilineal coast line from many sea regions surrounding Japan, and from the viewpoint of the flow and the diffusion characteristics, the sea region was classified into three patterns. 51 cases in total various parameters were obtained, and finally the simulation analysis was performed. (2) Drawing up the general use chart: 28 sheets of the computation chart for general use were drawn, which are available for computing the approximate temperature rise caused by the discharged warm water diffusion. The example of Anegasaki Thermal Power Station is given. (Kako, I.)

Fish-Friendly Pumping Stations Principles, Practices and Outcomes in Dutch Water Management

NARCIS (Netherlands)

Moria, Laura

2008-01-01

In the Netherlands polder water levels are managed with almost 3000 pumping stations that pump excess water from polders to reservoir canals or sea. These pumping stations might threaten Dutch fish stocks. Migrating fish are often unable to pass a pumping

Is Recovery of Large-Bodied Zooplankton after Nutrient Loading Reduction Hampered by Climate Warming? A Long-Term Study of Shallow Hypertrophic Lake Søbygaard, Denmark

Directory of Open Access Journals (Sweden)

María Florencia Gutierrez

2016-08-01

Full Text Available Nutrient fluctuations and climate warming can synergistically affect trophic dynamics in lakes, resulting in enhanced symptoms of eutrophication, thereby potentially counteracting restoration measures. We performed a long-term study (23 years of zooplankton in Danish Lake Søbygaard, which is in recovery after nutrient loading reduction, but now faces the effects of climate warming. We hypothesized that the recovery of large-bodied zooplankton after nutrient loading reduction would be hampered by climate warming through indirect effects on fish size structure. We found a shift in macrozooplankton from initial dominance of Daphnia spp. towards Bosmina spp. as well as a decline in the body size of copepods and an increase in the abundance of nauplii. These changes coincided with the increase in small sized fish as a result of rising water temperature. Despite a reduction in body size, the total biomass of cladocerans increased coinciding with a diminished fish catch per unit effort (CPUE, and likely then an overall reduction in the predation on zooplankton. A cascading effect to phytoplankton was evidenced by enhanced zooplankton:phytoplankton and cladoceran:phytoplankton ratios and a decrease in Chl-a:TP and Chl-a:TN ratios. Our results indicate that climate warming, through changes in the size structure of fish community, has major effects on zooplankton size structure. In Lake Søbygaard, the decline in zooplankton size did not prevent, but modulated, the positive cascading effect on phytoplankton through an expected diminished fish CPUE related to nutrient loading reduction.

Monitoring And Modeling Environmental Water Quality To Support Environmental Water Purchase Decision-making

Science.gov (United States)

Null, S. E.; Elmore, L.; Mouzon, N. R.; Wood, J. R.

2016-12-01

More than 25 million cubic meters (20,000 acre feet) of water has been purchased from willing agricultural sellers for environmental flows in Nevada's Walker River to improve riverine habitat and connectivity with downstream Walker Lake. Reduced instream flows limit native fish populations, like Lahontan cutthroat trout, through warm daily stream temperatures and low dissolved oxygen concentrations. Environmental water purchases maintain instream flows, although effects on water quality are more varied. We use multi-year water quality monitoring and physically-based hydrodynamic and water quality modeling to estimate streamflow, water temperature, and dissolved oxygen concentrations with alternative environmental water purchases. We simulate water temperature and dissolved oxygen changes from increased streamflow to prioritize the time periods and locations that environmental water purchases most enhance trout habitat as a function of water quality. Monitoring results indicate stream temperature and dissolved oxygen limitations generally exist in the 115 kilometers upstream of Walker Lake (about 37% of the study area) from approximately May through September, and this reach acts as a water quality barrier for fish passage. Model results indicate that low streamflows generally coincide with critically warm stream temperatures, water quality refugia exist on a tributary of the Walker River, and environmental water purchases may improve stream temperature and dissolved oxygen conditions for some reaches and seasons, especially in dry years and prolonged droughts. This research supports environmental water purchase decision-making and allows water purchase decisions to be prioritized with other river restoration alternatives.

Voluntary emergence and water detection in a newly recognized amphibious fish.

Science.gov (United States)

Magellan, K

2015-06-01

Galaxias 'nebula', a small fish which has adaptations for air-breathing but is not known to be amphibious, voluntarily emerged from water and, in an unfamiliar environment, moved preferentially towards an alternative water source. Nebula may thus be considered one of the few truly amphibious fishes, and their ability to detect water provides a selective advantage which aids their survival in unpredictable natural environments. © 2015 The Fisheries Society of the British Isles.

Characterization of Emulsions of Fish Oil and Water by Cryo Scanning Electron Microscopy

DEFF Research Database (Denmark)

Jensen, Louise Helene Søgaard; Horn, Anna Frisenfeldt; Jacobsen, Charlotte

Addition of fish oil to industrially prepared food products is attractive to the food industry because of the well-documented health effects of the omega 3 fatty acids in the fish oil [1]. Polyunsaturated Fatty Acids including omega 3 fatty acids are highly susceptible to lipid oxidation due...... to the many double bonds. Emulsions of fish oil in water are potential candidates for a delivery system of fish oil to food products. It has been suggested that oxidation of oil-in-water emulsions is initiated at the interface between oil and water. It has also been proposed that oxidation is to some extent...... is to characterize fish oil in water emulsions with respect to oil droplet size, distribution, and ultimately to view the structure and thickness of the interface layer. A freeze-fractured surface viewed at low temperatures under the scanning electron microscope is a promising strategy to reveal variations...

Water vapor changes under global warming and the linkage to present-day interannual variabilities in CMIP5 models

Science.gov (United States)

Takahashi, Hanii; Su, Hui; Jiang, Jonathan H.

2016-12-01

The fractional water vapor changes under global warming across 14 Coupled Model Intercomparison Project Phase 5 simulations are analyzed. We show that the mean fractional water vapor changes under global warming in the tropical upper troposphere between 300 and 100 hPa range from 12.4 to 28.0 %/K across all models while the fractional water vapor changes are about 5-8 %/K in other regions and at lower altitudes. The "upper-tropospheric amplification" of the water vapor change is primarily driven by a larger temperature increase in the upper troposphere than in the lower troposphere per degree of surface warming. The relative contributions of atmospheric temperature and relative humidity changes to the water vapor change in each model vary between 71.5 to 131.8 % and 24.8 to -20.1 %, respectively. The inter-model differences in the water vapor change is primarily caused by differences in temperature change, except over the inter-tropical convergence zone within 10°S-10°N where the model differences due to the relative humidity change are significant. Furthermore, we find that there is generally a positive correlation between the rates of water vapor change for long-tem surface warming and those on the interannual time scales. However, the rates of water vapor change under long-term warming have a systematic offset from those on the inter-annual time scales and the dominant contributor to the differences also differs for the two time scales, suggesting caution needs to be taken when inferring long-term water vapor changes from the observed interannual variations.

Mobile sailing robot for automatic estimation of fish density and monitoring water quality.

Science.gov (United States)

Koprowski, Robert; Wróbel, Zygmunt; Kleszcz, Agnieszka; Wilczyński, Sławomir; Woźnica, Andrzej; Łozowski, Bartosz; Pilarczyk, Maciej; Karczewski, Jerzy; Migula, Paweł

2013-07-01

The paper presents the methodology and the algorithm developed to analyze sonar images focused on fish detection in small water bodies and measurement of their parameters: volume, depth and the GPS location. The final results are stored in a table and can be exported to any numerical environment for further analysis. The measurement method for estimating the number of fish using the automatic robot is based on a sequential calculation of the number of occurrences of fish on the set trajectory. The data analysis from the sonar concerned automatic recognition of fish using the methods of image analysis and processing. Image analysis algorithm, a mobile robot together with its control in the 2.4 GHz band and full cryptographic communication with the data archiving station was developed as part of this study. For the three model fish ponds where verification of fish catches was carried out (548, 171 and 226 individuals), the measurement error for the described method was not exceeded 8%. Created robot together with the developed software has features for remote work also in the variety of harsh weather and environmental conditions, is fully automated and can be remotely controlled using Internet. Designed system enables fish spatial location (GPS coordinates and the depth). The purpose of the robot is a non-invasive measurement of the number of fish in water reservoirs and a measurement of the quality of drinking water consumed by humans, especially in situations where local sources of pollution could have a significant impact on the quality of water collected for water treatment for people and when getting to these places is difficult. The systematically used robot equipped with the appropriate sensors, can be part of early warning system against the pollution of water used by humans (drinking water, natural swimming pools) which can be dangerous for their health.

Seasonal variability of rocky reef fish assemblages: Detecting functional and structural changes due to fishing effects

Science.gov (United States)

Henriques, Sofia; Pais, Miguel Pessanha; Costa, Maria José; Cabral, Henrique Nogueira

2013-05-01

The present study analyzed the effects of seasonal variation on the stability of fish-based metrics and their capability to detect changes in fish assemblages, which is yet poorly understood despite the general idea that guilds are more resilient to natural variability than species abundances. Three zones subject to different levels of fishing pressure inside the Arrábida Marine Protected Area (MPA) were sampled seasonally. The results showed differences between warm (summer and autumn) and cold (winter and spring) seasons, with the autumn clearly standing out. In general, the values of the metrics density of juveniles, density of invertebrate feeders and density of omnivores increased in warm seasons, which can be attributed to differences in recruitment patterns, spawning migrations and feeding activity among seasons. The density of generalist/opportunistic individuals was sensitive to the effect of fishing, with higher values at zones with the lowest level of protection, while the density of individuals with high commercial value only responded to fishing in the autumn, due to a cumulative result of both juveniles and adults abundances during this season. Overall, this study showed that seasonal variability affects structural and functional features of the fish assemblage and that might influence the detection of changes as a result of anthropogenic pressures. The choice of a specific season, during warm sea conditions after the spawning period (July-October), seems to be more adequate to assess changes on rocky-reef fish assemblages.

Climate Change and Fish Availability

Science.gov (United States)

Teng, Paul P. S.; Lassa, Jonatan; Caballero-Anthony, Mely

Human consumption of fish has been trending upwards in the past decades and this is projected to continue. The main sources of fish are from wild fisheries (marine and freshwater) and aquaculture. Climate change is anticipated to affect the availability of fish through its effect on these two sources as well as on supply chain processes such as storage, transport, processing and retail. Climate change is known to result in warmer and more acid oceans. Ocean acidification due to higher CO2 concentration levels at sea modifies the distribution of phytoplankton and zooplankton to affect wild, capture fisheries. Higher temperature causes warm-water coral reefs to respond with species replacement and bleaching, leading to coral cover loss and habitat loss. Global changes in climatic systems may also cause fish invasion, extinction and turnover. While this may be catastrophic for small scale fish farming in poor tropical communities, there are also potential effects on animal protein supply shifts at local and global scales with food security consequences. This paper discusses the potential impacts of climate change on fisheries and aquaculture in the Asian Pacific region, with special emphasis on Southeast Asia. The key question to be addressed is “What are the impacts of global climate change on global fish harvests and what does it mean to the availability of fish?”

A Global Analysis of the Relationship between Concentrations of Microcystins in Water and Fish

Directory of Open Access Journals (Sweden)

Natalie M. Flores

2018-02-01

Full Text Available Cyanobacteria, the primary bloom-forming organisms in fresh water, elicit a spectrum of problems in lentic systems. The most immediate concern for people and animals are cyanobacterial toxins, which have been detected at variable concentrations in water and fish around the world. Cyanotoxins can transfer through food webs, potentially increasing the risk of exposure to people who eat fish from affected waters, yet little is known about how cyanotoxins fluctuate in wild fish tissues. We collated existing studies on cyanotoxins in fish and fresh water from lakes around the world into a global dataset to test the hypothesis that cyanotoxin concentrations in fish increase with water toxin concentrations. We limited our quantitative analysis to microcystins because data on other cyanotoxins in fish were sparse, but we provided a qualitative summary of other cyanotoxins reported in wild, freshwater fish tissues. We found a positive relationship between intracellular microcystin in water samples and microcystin in fish tissues that had been analyzed by assay methods (enzyme-linked immunosorbent assay and protein phosphatase inhibition assay. We expected microcystin to be found in increasingly higher concentrations from carnivorous to omnivorous to planktivorous fishes. We found, however, that omnivores generally had the highest tissue microcystin concentrations. Additionally, we found contrasting results for the level of microcystin in different tissue types depending on the toxin analysis method. Because microcystin and other cyanotoxins have the potential to impact public health, our results underline the current need for comprehensive and uniform detection methods for the analysis of cyanotoxins in complex matrices.

Research in thermal biology: Burning questions for coldwater stream fishes

Science.gov (United States)

McCullough, D.A.; Bartholow, J.M.; Jager, H.I.; Beschta, R.L.; Cheslak, E.F.; Deas, M.L.; Ebersole, J.L.; Foott, J.S.; Johnson, S.L.; Marine, K.R.; Mesa, M.G.; Petersen, J.H.; Souchon, Y.; Tiffan, K.F.; Wurtsbaugh, W.A.

2009-01-01

With the increasing appreciation of global warming impacts on ecological systems, in addition to the myriad of land management effects on water quality, the number of literature citations dealing with the effects of water temperature on freshwater fish has escalated in the past decade. Given the many biological scales at which water temperature effects have been studied, and the growing need to integrate knowledge from multiple disciplines of thermal biology to fully protect beneficial uses, we held that a survey of the most promising recent developments and an expression of some of the remaining unanswered questions with significant management implications would best be approached collectively by a diverse research community. We have identified five specific topic areas of renewed research where new techniques and critical thought could benefit coldwater stream fishes (particularly salmonids): molecular, organism, population/species, community and ecosystem, and policy issues in water quality. Our hope is that information gained through examination of recent research fronts linking knowledge at various scales will prove useful in managing water quality at a basin level to protect fish populations and whole ecosystems. Standards of the past were based largely on incipient lethal and optimum growth rate temperatures for fish species, while future standards should consider all integrated thermal impacts to the organism and ecosystem. ?? Taylor and Francis Group, LLC.

Impingement of juvenile and adult fishes during cooling water withdrawal

International Nuclear Information System (INIS)

McFarlane, R.W.

1978-01-01

Juvenile and adult fishes are impinged upon trash removal screens as Savannah River water is withdrawn for use on the Savannah River Plant (SRP). Thirty-six species of fish, representing half of all riverine species known from the area, were impinged on the screens at three SRP pumping stations during 1977. Based on the average of 11.2 fish impinged per day, annual impingement is estimated to be 4088 fish. SRP thus ranks third lowest for impingement recently reported for 33 electric power plants

Long lasting fish contamination with 90Sr of Ignalina NPP water cooling basin

International Nuclear Information System (INIS)

Dusauskiene-Duz, R.; Gudeliene, I.

2003-01-01

Between the nourishment chains in hydro ecosystem the main role have chain water-fish-man, because amount of 90 Sr in fish muscle is limited. 90 Sr accumulation and distribution between the fish organs and tissues was studied. It was found that the main way of 90 Sr enter to the Ignalina NPP water cooling basin fish is adsorption processes which is more active than that of absorption. Established regularities of distribution between the fish organs and tissues, which depends on the fish nourishment type and their species. We determined that 90 Sr activity in fish muscles increase from spring to autumn: in Rutilus rutilus - 8, Abramis brama - 6, Perca fluviatilis - 2,7 and Esox lucius - 22,3 times. We determined that 90 Sr activity in fish muscles is 24 times lower than permissible' standard. It was determined that 90 Sr activity in fish gonads is 2 times higher than that in muscles and depends on fish species. (author)

Formation of well-mixed warm water column in central Bohai Sea during summer: Role of high-frequency atmospheric forcing

Science.gov (United States)

Ma, Weiwei; Wan, Xiuquan; Wang, Zhankun; Liu, Yulong; Wan, Kai

2017-12-01

The influence of high-frequency atmospheric forcing on the formation of a well-mixed summer warm water column in the central Bohai Sea is investigated comparing model simulations driven by daily surface forcing and those using monthly forcing data. In the absence of high-frequency atmospheric forcing, numerical simulations have repeatedly failed to reproduce this vertically uniform column of warm water measured over the past 35 years. However, high-frequency surface forcing is found to strongly influence the structure and distribution of the well-mixed warm water column, and simulations are in good agreement with observations. Results show that high frequency forcing enhances vertical mixing over the central bank, intensifies downward heat transport, and homogenizes the water column to form the Bohai central warm column. Evidence presented shows that high frequency forcing plays a dominant role in the formation of the well-mixed warm water column in summer, even without the effects of tidal and surface wave mixing. The present study thus provides a practical and rational way of further improving the performance of oceanic simulations in the Bohai Sea and can be used to adjust parameterization schemes of ocean models.

Pharmaceuticals in water, fish and osprey nestlings in Delaware River and Bay

Science.gov (United States)

Bean, Thomas G.; Rattner, Barnett A.; Lazarus, Rebecca S.; Day, Daniel D.; Burket, S. Rebekah; Brooks, Bryan W.; Haddad, Samuel P.; Bowerman, William W.

2018-01-01

Exposure of wildlife to Active Pharmaceutical Ingredients (APIs) is likely to occur but studies of risk are limited. One exposure pathway that has received attention is trophic transfer of APIs in a water-fish-osprey food chain. Samples of water, fish plasma and osprey plasma were collected from Delaware River and Bay, and analyzed for 21 APIs. Only 2 of 21 analytes exceeded method detection limits in osprey plasma (acetaminophen and diclofenac) with plasma levels typically 2–3 orders of magnitude below human therapeutic concentrations (HTC). We built upon a screening level model used to predict osprey exposure to APIs in Chesapeake Bay and evaluated whether exposure levels could have been predicted in Delaware Bay had we just measured concentrations in water or fish. Use of surface water and BCFs did not predict API concentrations in fish well, likely due to fish movement patterns, and partitioning and bioaccumulation uncertainties associated with these ionizable chemicals. Input of highest measured API concentration in fish plasma combined with pharmacokinetic data accurately predicted that diclofenac and acetaminophen would be the APIs most likely detected in osprey plasma. For the majority of APIs modeled, levels were not predicted to exceed 1 ng/mL or method detection limits in osprey plasma. Based on the target analytes examined, there is little evidence that APIs represent a significant risk to ospreys nesting in Delaware Bay. If an API is present in fish orders of magnitude below HTC, sampling of fish-eating birds is unlikely to be necessary. However, several human pharmaceuticals accumulated in fish plasma within a recommended safety factor for HTC. It is now important to expand the scope of diet-based API exposure modeling to include alternative exposure pathways (e.g., uptake from landfills, dumps and wastewater treatment plants) and geographic locations (developing countries) where API contamination of the environment may represent greater risk.

Modelling the occurrence of postflexion stages of a marine estuarine-dependent fish in temperate South African estuaries

Directory of Open Access Journals (Sweden)

Yanasivan Kisten

2017-03-01

Full Text Available The movement of postflexion larvae of marine estuarine-dependent species into estuaries is critical for the survival of fishes reliant on estuaries as nurseries. However, detailed studies focused on environmental variability experienced by postflexion larvae entering a range of estuary types under varying conditions are rare. This study assessed the in situ conditions (temperature, salinity and water clarity under which the southern African endemic fish Rhabdosargus holubi (Sparidae recruits into estuaries. Postflexion larvae were sampled in three biogeographic regions (cool temperate, warm temperate and subtropical boundary, which included three estuary types (permanently open estuaries (POEs, temporarily open/closed estuaries and estuarine lake systems on a seasonal basis, independent of each other. Rhabdosargus holubi larvae were more abundant in spring and summer, in POEs in the warm temperate region. Models predicted that higher larval occurrence in estuaries is a function of lower salinity (e.g. mesohaline zones of 5-17.9 salinity and lower water clarity (e.g. 0-0.2 Kd, light extinction coefficient, particularly for warm, temperate POEs. This re-emphasizes the importance of freshwater for optimal nursery functioning, which may be compromised by impoundments, abstraction and climate change in water-short countries like South Africa.

Two decades of water vapor measurements with the FISH fluorescence hygrometer: a review

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J. Meyer

2015-07-01

Full Text Available For almost two decades, the airborne Fast In-situ Stratospheric Hygrometer (FISH has stood for accurate and precise measurements of total water mixing ratios (WMR, gas phase + evaporated ice in the upper troposphere and lower stratosphere (UT/LS. Here, we present a comprehensive review of the measurement technique (Lyman-α photofragment fluorescence, calibration procedure, accuracy and reliability of FISH. Crucial for FISH measurement quality is the regular calibration to a water vapor reference, namely the commercial frost-point hygrometer DP30. In the frame of this work this frost-point hygrometer is compared to German and British traceable metrological water standards and its accuracy is found to be 2–4 %. Overall, in the range from 4 to 1000 ppmv, the total accuracy of FISH was found to be 6–8 %, as stated in previous publications. For lower mixing ratios down to 1 ppmv, the uncertainty reaches a lower limit of 0.3 ppmv. For specific, non-atmospheric conditions, as set in experiments at the AIDA chamber – namely mixing ratios below 10 and above 100 ppmv in combination with high- and low-pressure conditions – the need to apply a modified FISH calibration evaluation has been identified. The new evaluation improves the agreement of FISH with other hygrometers to ± 10 % accuracy in the respective mixing ratio ranges. Furthermore, a quality check procedure for high total water measurements in cirrus clouds at high pressures (400–500 hPa is introduced. The performance of FISH in the field is assessed by reviewing intercomparisons of FISH water vapor data with other in situ and remote sensing hygrometers over the last two decades. We find that the agreement of FISH with the other hygrometers has improved over that time span from overall up to ± 30 % or more to about ± 5–20 % @ 10 ppmv. As presented here, the robust and continuous calibration and operation procedures of the FISH instrument over the last two decades establish the

Ethyl-p-aminobenzoate (Benzocaine): efficacy as an anesthetic for five species of freshwater fish

Science.gov (United States)

Dawson, V.K.; Gilderhus, P.A.

1979-01-01

Ethyl-p-aminobenzoate (benzocaine) was tested for its efficacy as an anesthetic for rainbow trout (Salmo gairdnerii, brown trout (Salmo truttas, northern pike (Esox lucius). carp (Cyprinus carpio), and largemouth bass (Mieropterus salmoidesi. Since benzocaine is not water soluble, it was applied with acetone as a carrier. Concentrations of 100 to 200 mg!l were required for large adult northern pike, compared with 50 to 100 mg/l for small fish. Rates of sedation and recovery were slower in cold water than in warm water. Water hardness had little influence on the activity of benzocaine. Fish were anesthetized faster and recovered more slowly in acid than in alkaline water. Benzocaine produced deep anesthesia, but concentrations that rendered the fish handleable within 5 min were generally not safe for exposures longer than 15 min. Concentrations of benzocaine efficacious for fish were not acutely toxic to eggs of coho salmon (Oncorhynchus kisutch), chinook salmon (Oncorhynchus tshauiytschas, rainbow trout, brown trout, or lake trout (Salvelinus namaycush). Benzocaine is not registered for fishery use and is neither more effective nor safer than the registered anesthetic, tricaine methanesulfonate (MS-222l.

The Effect of Water Temperature on Argulus foliaceus L. 1758 (Crustacea; Branchiura on Different Fish Species

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Mustafa KOYUN

2011-05-01

Full Text Available Parasites belonging to Argulus genus, known as fish louse (Argulus foliaceus L. significantly affect in negative way both in natural and farming environment. In this study, the pathogenic effect of fish louse temperature on fish depending on water was investigated. In this research to estimate the effects of several factors such as water temperature, gender of the fish and the infection of fish louse were studied through Poisson regression method. As fish species, Alburnus alburnus (bleak, Carassius carassius (crucian carp and Carassius auratus (golden carp were caught periodically, starting from May during the year, and the parasites were counted. The gender and metrical measures of the examined fish were categorized separately. The degrees of water temperature of the dam were measured. Results from Poisson regression analysis showed that fish louse has harmful effect on the mentioned fish, depending on the water temperature.

Cultivo y Manejo de Estanques Pesqueros de Agua Fresca (Freshwater Fish Pond Culture and Management). Appropriate Technologies for Development. Manual M-1D.

Science.gov (United States)

Chakroff, Marilyn; Druben, Laurel, Ed.

This is the Spanish translation of a "how-to" manual, designed as a working and teaching tool for extension agents as they establish and/or maintain local fish pond operations. The manual presents information to facilitate technology transfer and to provide a clear guide for warm water fish pond construction and management. Major topic…

Warm Water Compress as an Alternative for Decreasing the Degree of Phlebitis.

Science.gov (United States)

Annisa, Fitri; Nurhaeni, Nani; Wanda, Dessie

Intravenous fluid therapy is an invasive procedure which may increase the risk of patient complications. One of the most common of these is phlebitis, which may cause discomfort and tissue damage. Therefore, a nursing intervention is needed to effectively treat phlebitis. The purpose of this study was to investigate the effectiveness of applying a warm compression intervention to reduce the degree of phlebitis. A quasi-experimental pre-test and post-test design was used, with a non-equivalent control group. The total sample size was 32 patients with degrees of phlebitis ranging from 1 to 4. The total sample was divided into 2 interventional groups: those patients that were given 0.9% NaCl compresses and those given warm water compresses. The results showed that both compresses were effective in reducing the degree of phlebitis, with similar p values (p = .000). However, there was no difference in the average reduction score between the two groups (p = .18). Therefore, a warm water compress is valuable in the treatment of phlebitis, and could decrease the degree of phlebitis both effectively and inexpensively.

Soil warming increased whole-tree water use of Pinus cembra at the treeline in the Central Tyrolean Alps.

Science.gov (United States)

Wieser, Gerhard; Grams, Thorsten E E; Matyssek, Rainer; Oberhuber, Walter; Gruber, Andreas

2015-03-01

This study quantified the effect of soil warming on sap flow density (Qs) of Pinus cembra L. at the treeline in the Central Tyrolean Alps. To enhance soil temperature we installed a transparent roof construction above the forest floor around six trees. Six other trees served as controls in the absence of any manipulation. Roofing enhanced growing season mean soil temperature by 1.6, 1.3 and 1.0 °C at 5, 10 and 20 cm soil depth, respectively, while soil water availability was not affected. Sap flow density (using Granier-type thermal dissipation probes) and environmental parameters were monitored throughout three growing seasons. During the first year of treatment, no warming effect was detected on Qs. However, soil warming caused Qs to increase significantly by 11 and 19% above levels in control trees during the second and third year, respectively. This effect appeared to result from warming-induced root production, a reduction in viscosity and perhaps an increase also in root hydraulic conductivity. Hardly affected were leaf-level net CO2 uptake rate and conductance for water vapour, so that water-use efficiency stayed unchanged as confirmed by needle δ(13)C analysis. We conclude that tree water loss will increase with soil warming, which may alter the water balance within the treeline ecotone of the Central Austrian Alps in a future warming environment. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Water transport and functional dynamics of aquaporins in osmoregulatory organs of fishes

DEFF Research Database (Denmark)

Madsen, Steffen S; Engelund, Morten B; Cutler, Christopher P

2015-01-01

salty desert lakes, the challenge to obtain consensus as well as specific knowledge about aquaporin physiology in these vertebrate clades is overwhelming. Because the integumental surfaces of these animals are in intimate contact with the surrounding milieu, passive water loss and uptake represent two......Aquaporins play distinct roles for water transport in fishes as they do in mammals-both at the cellular, organ, and organismal levels. However, with over 32,000 known species of fishes inhabiting almost every aquatic environment, from tidal pools, small mountain streams, to the oceans and extreme...... of the major osmoregulatory challenges that need compensation. However, neither obligatory nor regulatory water transport nor their mechanisms have been elucidated to the same degree as, for example, ion transport in fishes. Currently fewer than 60 papers address fish aquaporins. Most of these papers identify...

Role of Stratospheric Water Vapor in Global Warming from GCM Simulations Constrained by MLS Observation

Science.gov (United States)

Wang, Y.; Stek, P. C.; Su, H.; Jiang, J. H.; Livesey, N. J.; Santee, M. L.

2014-12-01

Over the past century, global average surface temperature has warmed by about 0.16°C/decade, largely due to anthropogenic increases in well-mixed greenhouse gases. However, the trend in global surface temperatures has been nearly flat since 2000, raising a question regarding the exploration of the drivers of climate change. Water vapor is a strong greenhouse gas in the atmosphere. Previous studies suggested that the sudden decrease of stratospheric water vapor (SWV) around 2000 may have contributed to the stall of global warming. Since 2004, the SWV observed by Microwave Limb Sounder (MLS) on Aura satellite has shown a slow recovery. The role of recent SWV variations in global warming has not been quantified. We employ a coupled atmosphere-ocean climate model, the NCAR CESM, to address this issue. It is found that the CESM underestimates the stratospheric water vapor by about 1 ppmv due to limited representations of the stratospheric dynamic and chemical processes important for water vapor variabilities. By nudging the modeled SWV to the MLS observation, we find that increasing SWV by 1 ppmv produces a robust surface warming about 0.2°C in global-mean when the model reaches equilibrium. Conversely, the sudden drop of SWV from 2000 to 2004 would cause a surface cooling about -0.08°C in global-mean. On the other hand, imposing the observed linear trend of SWV based on the 10-year observation of MLS in the CESM yields a rather slow surface warming, about 0.04°C/decade. Our model experiments suggest that SWV contributes positively to the global surface temperature variation, although it may not be the dominant factor that drives the recent global warming hiatus. Additional sensitivity experiments show that the impact of SWV on surface climate is mostly governed by the SWV amount at 100 hPa in the tropics. Furthermore, the atmospheric model simulations driven by observed sea surface temperature (SST) show that the inter-annual variation of SWV follows that of SST

Predicting Fish Growth Potential and Identifying Water Quality Constraints: A Spatially-Explicit Bioenergetics Approach

Science.gov (United States)

Budy, Phaedra; Baker, Matthew; Dahle, Samuel K.

2011-10-01

Anthropogenic impairment of water bodies represents a global environmental concern, yet few attempts have successfully linked fish performance to thermal habitat suitability and fewer have distinguished co-varying water quality constraints. We interfaced fish bioenergetics, field measurements, and Thermal Remote Imaging to generate a spatially-explicit, high-resolution surface of fish growth potential, and next employed a structured hypothesis to detect relationships among measures of fish performance and co-varying water quality constraints. Our thermal surface of fish performance captured the amount and spatial-temporal arrangement of thermally-suitable habitat for three focal species in an extremely heterogeneous reservoir, but interpretation of this pattern was initially confounded by seasonal covariation of water residence time and water quality. Subsequent path analysis revealed that in terms of seasonal patterns in growth potential, catfish and walleye responded to temperature, positively and negatively, respectively; crappie and walleye responded to eutrophy (negatively). At the high eutrophy levels observed in this system, some desired fishes appear to suffer from excessive cultural eutrophication within the context of elevated temperatures whereas others appear to be largely unaffected or even enhanced. Our overall findings do not lead to the conclusion that this system is degraded by pollution; however, they do highlight the need to use a sensitive focal species in the process of determining allowable nutrient loading and as integrators of habitat suitability across multiple spatial and temporal scales. We provide an integrated approach useful for quantifying fish growth potential and identifying water quality constraints on fish performance at spatial scales appropriate for whole-system management.

Impacts of alum residues from Morton Jaffray Water Works on water quality and fish, Harare, Zimbabwe

Science.gov (United States)

Muisa, Norah; Hoko, Zvikomborero; Chifamba, Portia

Metal pollution of freshwater due to human activities is a major problem confronting most urban centres in developing countries. This study determined the extent to which aluminium in the residues from Morton Jaffray Water Works in Harare were affecting the water quality of Manyame River and Lake Manyame. The study also measured aluminium bioaccumulation in Nile Tilapia ( Oreochromis niloticus) which is of importance to the commercial fisheries industry in Zimbabwe. Depth integrated water, and sediment grab samples and adult fish were collected per site in January and March, 2010. A total of six sites were selected on the Manyame River and in Lake Manyame. The levels of Total Aluminium (Al) were determined in sediments, water and fish tissues (liver, kidney, gill and muscle). Total solids, total dissolved solids, conductivity, pH, dissolved oxygen and temperature were also determined in water and residues. The texture of the sediments was also assessed. Aluminium concentration in water ranged from 2.19 mg/L to 68.93 mg/L during both sampling campaigns surpassing permissible maximum concentration limits of 0.087 to 0.75 mg/L suggested by the Environmental Protection Agency and African Union. The site upstream of the discharge point of the residues always had the lowest levels though it was higher than acceptable levels indicated above, thus suggesting the existence of other sources of aluminium in the catchment besides Morton Jaffray Water Works. However, there was a 10-fold and 100-fold increase in levels of aluminium in water and sediments, respectively, at the site 100 m downstream of the discharge point on the Manyame River. Mean aluminium concentrations in water and sediments at this site averaged 68.93 ± 61.74 mg/L and 38.18 ± 21.54 mg/L in water and 103.79 ± 55.96 mg/L and 131.84 ± 16.48 mg/L in sediments in sampling campaigns 1 and 2, respectively. These levels were significantly higher than levels obtained from all the other sites during both sampling

Seasonal and interannual effects of hypoxia on fish habitat quality in central Lake Erie

Science.gov (United States)

Arend, Kristin K.; Beletsky, Dmitry; DePinto, Joseph; Ludsin, Stuart A.; Roberts, James J.; Rucinski, Daniel K.; Scavia, Donald; Schwab, David J.; Höök, Tomas O.

2011-01-01

1. Hypoxia occurs seasonally in many stratified coastal marine and freshwater ecosystems when bottom dissolved oxygen (DO) concentrations are depleted below 2–3 mg O2 L-1. 2. We evaluated the effects of hypoxia on fish habitat quality in the central basin of Lake Erie from 1987 to 2005, using bioenergetic growth rate potential (GRP) as a proxy for habitat quality. We compared the effect of hypoxia on habitat quality of (i) rainbow smelt, Osmerus mordax mordax Mitchill (young-of-year, YOY, and adult), a cold-water planktivore, (ii) emerald shiner, Notropis atherinoides Rafinesque (adult), a warm-water planktivore, (iii) yellow perch, Perca flavescens Mitchill (YOY and adult), a cool-water benthopelagic omnivore and (iv) round goby Neogobius melanostomus Pallas (adult) a eurythermal benthivore. Annual thermal and DO profiles were generated from 1D thermal and DO hydrodynamics models developed for Lake Erie’s central basin. 3. Hypoxia occurred annually, typically from mid-July to mid-October, which spatially and temporally overlaps with otherwise high benthic habitat quality. Hypoxia reduced the habitat quality across fish species and life stages, but the magnitude of the reduction varied both among and within species because of the differences in tolerance to low DO levels and warm-water temperatures. 4. Across years, trends in habitat quality mirrored trends in phosphorus concentration and water column oxygen demand in central Lake Erie. The per cent reduction in habitat quality owing to hypoxia was greatest for adult rainbow smelt and round goby (mean: -35%), followed by adult emerald shiner (mean: -12%), YOY rainbow smelt (mean: -10%) and YOY and adult yellow perch (mean: -8.5%). 5. Our results highlight the importance of differential spatiotemporally interactive effects of DO and temperature on relative fish habitat quality and quantity. These effects have the potential to influence the performance of individual fish species as well as population dynamics

Recent warming of lake Kivu.

Science.gov (United States)

Katsev, Sergei; Aaberg, Arthur A; Crowe, Sean A; Hecky, Robert E

2014-01-01

Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient.

Recent warming of lake Kivu.

Directory of Open Access Journals (Sweden)

Sergei Katsev

Full Text Available Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient.

Demersal fishes and their distribution in estuarine waters of Mahakam Delta, East Kalimantan

Directory of Open Access Journals (Sweden)

IWAN SUYATNA

2010-10-01

Full Text Available Suyatna I, Bratawinata AA, Sidik AS, Ruchaemi A (2011 Demersal fishes and their distribution in estuarine waters of Mahakam Delta, East Kalimantan. Biodiversitas 12: 204-210. The study aimed (i to identify of the demersal fishes, (ii to analyze the diversity and (iii to determine their distribution. Surveys were carried out between August 2009 and January 2010 in Mahakam Delta, East Kalimantan. Data were analyzed using several indices of Shannon Weaver, Sympson, Margalef species richness, and Bray Curtis distance. The canonical correspondence analysis (CCA was also used to correlate between fish species and their environmental factors and to show the fish distribution. Sixty samplings were done using bottom-trawl at various water depths from one to fourty two meters to collect the data. Taxonomically, during the study, 10 orders, 61 families, 87 genera and 131 species of fish with 43340 individuals were identified. Among the families, Leiognathidae was the most important group of fish, they distributed throughout the depths. Meanwhile CCA showed that Leiognathidae and Sciaenidae were observed to be rich in the shallow water. Generally, index of Shannon Weaver, Sympson and Margalef species richness ranged between; 0.52 and 2.48; 0.11 and 0.82; 2.24 and 18.61 respectively. Bray Curtis distance indicated the significant difference of individual number of demersal fishes between shallow and deep waters.

Water for fish, water for power : finding a balance

International Nuclear Information System (INIS)

1998-08-01

The impact of British Columbia Hydro's operations on the 100 different species and sub-species of fish found in the rivers of BC is discussed. The utility operates 30 hydroelectric facilities and 31 reservoirs in 6 major river basins and 27 watersheds. Three-quarters of the hydroelectricity is produced at major installations on the Peace and Columbia river systems. This booklet describes how, in their water use planning and decision-making, the utility considers impacts on aquatic and terrestrial habitats, flood control, domestic water supply and transport, as well as aesthetic requirements and recreational use. figs

Analysis on traditional fishing grounds in Indonesia`s Natuna waters under International Law

Science.gov (United States)

Kurniaty, R.; Ikaningtyas; Ruslijanto, P. A.

2018-04-01

This paper examines the boundary tension between Indonesia and China regarding traditional fishing ground in Natuna. Indonesia`s Natuna island is claimed by the China government as its traditional fishing zone/ground. The inclusion of Natuna territory into China`s traditional fishing zone brings new problems to Indonesia, especially with the Chinese ships docked and entered Indonesia`s exclusive economic zone, as well as several cases of illegal fishing over the territorial waters of Indonesia. Claims on traditional fishing zones have the potential to threaten the sovereignty of the Indonesian territory. This study aims to analyze the claims of the traditional fishing rights of China over the waters of the Natuna Islands under international law, especially UNCLOS 1982. This study revealed that the china`s argument of traditional fishing ground in Natuna to the nine dash line map is a unilateral claim, there is no international legal norm that can be used as the legal basis. Indonesia and some ASEAN countries have Internationally validated bilateral agreement on the continental shelf (i.e. Indonesia-Vietnam and Indonesia-Malaysia) thus the inclusion of Natuna into China`s nine dash line map rejects the legal status of Indonesian water under UNCLOS 1982.

Fish gill responses to pollutants from oil sands mining-associated waters

International Nuclear Information System (INIS)

Lee, L.E.J.; Willfang, S.; Lamb, M.P.; Nero, V.; Farwell, A.J.; Dixon, D.G.

2002-01-01

The processing of Athabasca Deposit oil sands results in large amounts of liquid wastes associated with oil sand tailings. In addition to containing polycyclic aromatic hydrocarbons (PAHs), these waste waters are high in salinity and naphthenic acids which may be toxic to aquatic biota and their effects must be clarified. This study presents a suite of tests for in-depth and quick analysis of tailings water toxicity and contributes to the assessment of environmental risk. Yellow perch, fathead minnows, and rainbow trout were exposed to reclamation ponds where both in vivo and in vitro evaluation of crude and individual naphthenic acids and salts were conducted to examine their effect on fish gills which are very susceptible to contaminants. The fish exposed to the reclamation ponds showed higher incidence of gill pathological changes than control fish in Mildred Lake, a reservoir lake whose waters are diverted for use in oil sands extraction. Notable gill histopathological changes were observed when fish were exposed in vivo to sulfate/chloride salts and to abietic acid. Changes in membrane integrity, lysosomal activity and general morphology were observed when fished were exposed in vitro to salts, commercial napthenic acids or crude naphthenic extracts from the reclamation ponds

Long-term effects of extreme weather events and eutrophication on the fish community of shallow Lake Peipsi (Estonia/Russia

Directory of Open Access Journals (Sweden)

Külli Kangur

2013-06-01

Full Text Available The fish kill in lake Peipsi (Estonia/Russia during the extraordinarily hot summer of 2010 evoked an investigation into the effects of environmental extremes and long-term eutrophication on the fish community of the lake. Current data on lake Peipsi indicate that temperature extremes and synergistic interactions with eutrophication have led to a radical restructuring of the fish community. Commercial landings of lake smelt, Osmerus eperlanus eperlanus m. spirinchus (Pallas, the previous dominant species of the fish community, have decreased dramatically since the 1930s, these declines being coupled with summer heat waves coinciding with low water levels. Gradual decline in smelt stock and catches was significantly related to a decline of near-bottom oxygen conditions and to a decrease in water transparency. The first documented fish kill in 1959 occurred only in the southern, most shallow and eutrophic lake (lake Pihkva. Recently, summer fish kill have become more frequent, involving larger areas of the lake. In addition to the cold-water species, e.g. smelt and vendace Coregonus albula (L., the abundance of bottom-dwelling fishes such as ruffe Gymnocephalus cernuus (L. and juvenile fish have significantly decreased after the 2010 heat wave probably due to hypoxia and warm water temperatures. This study showed that fish community structure in large shallow lakes may be very vulnerable to water temperature increases, especially temperature extremes in combination with eutrophication.

ECONOMETRIC MODELLING OD THE INFLUENCE OF LAKE WATER QUALITY CHANGES ON FISHING ECONOMY

Directory of Open Access Journals (Sweden)

Marek Antoni Ramczyk

2017-06-01

Full Text Available The econometric model can be a precise instrument for the analysis of the impact of the natural environment's degradation on fishing economy. This paper aims at analysing the influence of the water quality changes in lake Charzykowskie on the fishing economy. This dissertation present the results of a research on the lake water pollution's impact on fishing economy. The economic-ecological models have been constructed, explaining the changes of economic effects of the lake fishery in the conditions of an increasing water pollution in the epilimnion on the example of the catch of Rutilus rutilus, Abramis brama, Blicca bjoerkna, Coregonus albula, Coregonus lavaretus, Anguilla anguilla and Esox lucius in Lake Charzykowskie. Performed empirical research looked into the influence of the environmental factors on the size of fish catch. Calculations and analysis show clearly that though the habitat factors do influence the catch size of each studied fish species, they do it with different intensity and in various combinations. Both lake water quality and climate factors changes cause measurable effects on fishing industry of lake Charzykowskie. Among all the examined Rutilus rutilus, Abramis brama and Blicca bjoerkna the highest environmental requirements concerning water quality has Blicca bjoerkna. Whereas Abramis brama has slightly higher environmental requirements than Rutilus rutilus. Empirical calculations showed as well that Coregonus albula and Coregonus lavaretus have considerably higher water cleanness requirements than Rutilus rutilus, Abramis brama and Blicca bjoerkna. While when talking about Rutilus rutilus, Abramis brama and Blicca bjoerkna, most water characteristics still rather stimulated these species' development, when it comes to Coregonus albula and Coregonus lavaretus, in general they suppressed their development. The model has also proved quite high habitat requierements of Anquilla anquilla and correctness of the thesis that

Assessment of heavy metal residues in water, fish tissue and human ...

African Journals Online (AJOL)

MICHAEL HORSFALL

ABSTRACT: Residual levels of lead, chromium, cadmium and zinc in water and fish tissue from. Ubeji River ... Key Words : Heavy metal residues , Fish tissue, Human blood, Ubeji River. ... is of critical concern because of their toxicity and.

Ichthyoplankton Time Series: A Potential Ocean Observing Network to Provide Indicators of Climate Impacts on Fish Communities along the West Coast of North America

Science.gov (United States)

Koslow, J. A.; Brodeur, R.; Duffy-Anderson, J. T.; Perry, I.; jimenez Rosenberg, S.; Aceves, G.

2016-02-01

Ichthyoplankton time series available from the Bering Sea, Gulf of Alaska and California Current (Oregon to Baja California) provide a potential ocean observing network to assess climate impacts on fish communities along the west coast of North America. Larval fish abundance reflects spawning stock biomass, so these data sets provide indicators of the status of a broad range of exploited and unexploited fish populations. Analyses to date have focused on individual time series, which generally exhibit significant change in relation to climate. Off California, a suite of 24 midwater fish taxa have declined > 60%, correlated with declining midwater oxygen concentrations, and overall larval fish abundance has declined 72% since 1969, a trend based on the decline of predominantly cool-water affinity taxa in response to warming ocean temperatures. Off Oregon, there were dramatic differences in community structure and abundance of larval fishes between warm and cool ocean conditions. Midwater deoxygenation and warming sea surface temperature trends are predicted to continue as a result of global climate change. US, Canadian, and Mexican fishery scientists are now collaborating in a virtual ocean observing network to synthesize available ichthyoplankton time series and compare patterns of change in relation to climate. This will provide regional indicators of populations and groups of taxa sensitive to warming, deoxygenation and potentially other stressors, establish the relevant scales of coherence among sub-regions and across Large Marine Ecosystems, and provide the basis for predicting future climate change impacts on these ecosystems.

Tides, the PIG, and 'warm' water

International Nuclear Information System (INIS)

Robertson, Robin

2010-01-01

The present rapid melting of the Pine Island Glacier (PIG) has been attributed to basal melting driven by the ocean. Specifically, this ocean melting is attributed to currents and tides pumping 'warm' Circumpolar Deep Water (CDW) into the ice shelf cavity. To identify tidal activity in the region, an observational time series of yo-yo CTD (Conductivity, Temperature, and Depth) data collected in the PIG outflow region was analyzed. The water column in front of the PIG consisted of two primary layers, a meltwater layer exiting the ice shelf cavity over a layer of CDW. Semidiurnal tides were present in both layers, with both the strength and direction of the tides differing between the two layers. The upper layer tides were stronger and directed in and out of the cavity, while the lower layer tides were primarily directed along the front of the cavity. Energy was found to be transferred from the semidiurnal tide to other frequencies and to be reflected by the ice shelf front. These mechanisms were most prominent at the interfaces between layers and indicate potential mixing between the layers. In conclusion, tides were found to contribute to the circulation into the ice shelf cavity and also to mixing of the exiting water, which influences pumping of the CDW into the ice shelf cavity and melting of the PIG.

Phase I Water Rental Pilot Project : Snake River Resident Fish and Wildlife Resources and Management Recommendations.

Energy Technology Data Exchange (ETDEWEB)

Riggin, Stacey H.; Hansen, H. Jerome

1992-10-01

The Idaho Water Rental Pilot Project was implemented as a part of the Non-Treaty Storage Fish and Wildlife Agreement (NTSA) between Bonneville Power Administration and the Columbia Basin Fish and Wildlife Authority. The goal of the project is to improve juvenile and adult salmon and steelhead passage in the lower Snake River with the use of rented water for flow augmentation. The primary purpose of this project is to summarize existing resource information and provide recommendations to protect or enhance resident fish and wildlife resources in Idaho with actions achieving flow augmentation for anadromous fish. Potential impacts of an annual flow augmentation program on Idaho reservoirs and streams are modeled. Potential sources of water for flow augmentation and operational or institutional constraints to the use of that water are identified. This report does not advocate flow augmentation as the preferred long-term recovery action for salmon. The state of Idaho strongly believes that annual drawdown of the four lower Snake reservoirs is critical to the long-term enhancement and recovery of salmon (Andrus 1990). Existing water level management includes balancing the needs of hydropower production, irrigated agriculture, municipalities and industries with fish, wildlife and recreation. Reservoir minimum pool maintenance, water quality and instream flows are issues of public concern that will be directly affected by the timing and quantity of water rental releases for salmon flow augmentation, The potential of renting water from Idaho rental pools for salmon flow augmentation is complicated by institutional impediments, competition from other water users, and dry year shortages. Water rental will contribute to a reduction in carryover storage in a series of dry years when salmon flow augmentation is most critical. Such a reduction in carryover can have negative impacts on reservoir fisheries by eliminating shoreline spawning beds, reducing available fish habitat

Patterns of fish assemblage structure and dynamics in waters of the Savannah River Plant. Comprehensive Cooling Water Study final report

Energy Technology Data Exchange (ETDEWEB)

Aho, J.M.; Anderson, C.S.; Floyd, K.B.; Negus, M.T.; Meador, M.R.

1986-06-01

Research conducted as part of the Comprehensive Cooling Water Study (CCWS) has elucidated many factors that are important to fish population and community dynamics in a variety of habitats on the Savannah River Plant (SRP). Information gained from these studies is useful in predicting fish responses to SRP operations. The overall objective of the CCWS was (1) to determine the environmental effects of SRP cooling water withdrawals and discharges and (2) to determine the significance of the cooling water impacts on the environment. The purpose of this study was to: (1) examine the effects of thermal plumes on anadromous and resident fishes, including overwintering effects, in the SRP swamp and associated tributary streams; (2) assess fish spawning and locate nursery grounds on the SRP; (3) examine the level of use of the SRP by spawning fish from the Savannah River, this objective was shared with the Savannah River Laboratory, E.I. du Pont de Nemours and Company; and (4) determine impacts of cooling-water discharges on fish population and community attributes. Five studies were designed to address the above topics. The specific objectives and a summary of the findings of each study are presented.

Quantitative assessment of accumulation of radionuclides in fish organism in dependence on water temperature

International Nuclear Information System (INIS)

Katkov, A.E.

1980-01-01

Eperimentally studied are the changes of levels of several indices of radionuclide metabolism in fishes in dependence on water temperature at its absorption directly from water and at introduction into the digestive tract. Presented are the coefficients of radionuclide storage by the fish tissues in the dependence on temperature (scales and fins, gills, head, intestines, skin, muscles, axial skeleton) and the coefficients of radionuclide retention in the whole fish. It is shown that the connection between the coefficient of radionuclide storage in the fish organism and water temperature is described by the logarithmic dependence. At the systematic entering of radionuclides into the digestive tract the retention coefficient of them in the organism expressed in the form of the ratio of residual quantity in the fish to the quantity in day dose is constant

A case study of life cycle impacts of small-scale fishing techniques in Thailand

DEFF Research Database (Denmark)

Verones, Francesca; Bolowich, Alya F.; Ebata, Keigo

2017-01-01

Fish provides an important source of protein, especially in developing countries, and the amounts of fish consumed are increasing worldwide (mostly from aquaculture). More than half of all marine fish are caught by small-scale fishery operations. However, no life cycle assessment (LCA) of small...... inventories for three different seasons (northeast monsoon, southwest monsoon and pre-monsoon), since the time spent on the water and catch varied significantly between the seasons. Our results showed the largest impacts from artisanal fishing operations affect climate change, human toxicity, and fossil...... and metal depletion. Our results are, in terms of global warming potential, comparable with other artisanal fisheries. Between different fishing operations, impacts vary between a factor of 2 (for land transformation impacts) and up to a factor of more than 20 (fossil fuel depletion and marine...

Uniquely significant fresh water fishes of Iran are exposure to environmental stress

International Nuclear Information System (INIS)

Valeolahy, J.

2000-01-01

The native fishes of springs, Ghana ts and Caves of Iran are uniquely significant, since they are rear and, because of pollution, dryness, purposeful or accidental introduction of exotic species and over all, because of industrialization are in danger. The stock of valuable fishes of Iran are declining while they have not been completely identified. The stock of these fishes, particular y those of economic value, such as large Bar bus sp. at western part of Iran are declining. In an attempt fishes among the 140 station and average of three unit of effort for catch of fish in every station (total of 400 unit of effort) about 80 specimen of large Bar bus were caught. Fishes were caught by electroshock and various kind of net with mesh size of 2 cm to 4 cm. The Gamasib River was known to have large Carp, but this result showed that nowadays the stock of large Bar bus substantially damaged. The stock of: B. subquincunciatus and B. grypus severely damaged. The purpose of this paper is to describe those factors, which affect the stock and abundance of Iranian freshwater fishes, and to suggest measures for the conservation of this fauna. These factors include pre-industrial, and such factors related to industrialization and population increases as de vegetation, water abstracting, fishing, pollution and faun al introductions. Introduction of new species to increase fish production and exploit the fishery potential of water bodies, can be great utility; but has many hazardous impacts on native species, Biodiversity and Ecology of the Water bodies. Some aspect of theses impacts are outlined

TOPEX/El Nino Watch - Warm Water Pool is Thinning, Feb, 5, 1998

Science.gov (United States)

1998-01-01

This image of the Pacific Ocean was produced using sea surface height measurements taken by the U.S.-French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Feb. 5, 1998 and sea surface height is an indicator of the heat content of the ocean. The area and volume of the El Nino warm water pool that is affecting global weather patterns remains extremely large, but the pool has thinned along the equator and near the coast of South America. This 'thinning' means that the warm water is not as deep as it was a few months ago. Oceanographers indicate this is a classic pattern, typical of a mature El Nino condition that they would expect to see during the ocean's gradual transition back to normal sea level. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level. The El Nino phenomenon is thought to be triggered when the steady westward blowing trade winds weaken and even reverse direction. This change in the winds allows a large mass of warm water (the red and white area) that is normally located near Australia to move eastward along the equator until it reaches the coast of South America. The displacement of so much warm water affects evaporation, where rain clouds form and, consequently, alters the typical atmospheric jet stream patterns around the world. Using satellite imagery, buoy and ship data, and a forecasting model of the ocean-atmosphere system, the National Oceanic and Atmospheric Administration, (NOAA), has continued to issue an advisory indicating the so-called El Nino weather conditions that have impacted much of the United States and the world are expected to remain through

Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems

NARCIS (Netherlands)

Rix, L.; de Goeij, J.M.; Mueller, C.E.; Struck, U.; Middelburg, J.J.; van Duyl, F.C.; Al-Horani, F.A.; Wild, C.; Naumann, M.S.; Van Oevelen, D.

2016-01-01

Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and

Benefit of warm water immersion on biventricular function in patients with chronic heart failure

Directory of Open Access Journals (Sweden)

Kardassis Dimitris

2009-07-01

Full Text Available Abstract Background Regular physical activity and exercise are well-known cardiovascular protective factors. Many elderly patients with heart failure find it difficult to exercise on land, and hydrotherapy (training in warm water could be a more appropriate form of exercise for such patients. However, concerns have been raised about its safety. The aim of this study was to investigate, with echocardiography and Doppler, the acute effect of warm water immersion (WWI and effect of 8 weeks of hydrotherapy on biventricular function, volumes and systemic vascular resistance. A secondary aim was to observe the effect of hydrotherapy on brain natriuretic peptide (BNP. Methods Eighteen patients [age 69 ± 8 years, left ventricular ejection fraction 31 ± 9%, peakVO2 14.6 ± 4.5 mL/kg/min] were examined with echocardiography on land and in warm water (34°C. Twelve of these patients completed 8 weeks of control period followed by 8 weeks of hydrotherapy twice weekly. Results During acute WWI, cardiac output increased from 3.1 ± 0.8 to 4.2 ± 0.9 L/min, LV tissue velocity time integral from 1.2 ± 0.4 to 1.7 ± 0.5 cm and right ventricular tissue velocity time integral from 1.6 ± 0.6 to 2.5 ± 0.8 cm (land vs WWI, p There was no change in the cardiovascular response or BNP after 8 weeks of hydrotherapy. Conclusion Hydrotherapy was well tolerated by all patients. The main observed cardiac effect during acute WWI was a reduction in heart rate, which, together with a decrease in afterload, resulted in increases in systolic and diastolic biventricular function. Although 8 weeks of hydrotherapy did not improve cardiac function, our data support the concept that exercise in warm water is an acceptable regime for patients with heart failure.

Drifting algae and fish: Implications of tropical Sargassum invasion due to ocean warming in western Japan

Science.gov (United States)

Yamasaki, Mami; Aono, Mikina; Ogawa, Naoto; Tanaka, Koichiro; Imoto, Zenji; Nakamura, Yohei

2014-06-01

Evidence is accumulating that the invasion and extinction of habitat-forming seaweed species alters coastal community structure and ecological services, but their effects on the pelagic environment have been largely ignored. Thus, we examined the seasonal occurrence patterns of indigenous temperate and invasive tropical drifting algae and associated fish species every month for 2 years (2009-2011) in western Japan (Tosa Bay), where a rapid shift from temperate to tropical Sargassum species has been occurring in the coastal area since the late 1980s due to rising seawater temperatures. Of the 19 Sargassum species (31.6%) in drifting algae, we found that six were tropical species, whereas a study in the early 1980s found only one tropical species among 12 species (8.3%), thereby suggesting an increase in the proportion of tropical Sargassum species in drifting algae during the last 30 years. Drifting temperate algae were abundantly present from late winter to summer, whereas tropical algal clumps occurred primarily during summer. In the warm season, fish assemblages did not differ significantly between drifting temperate and tropical algae, suggesting the low host-algal specificity of most fishes. We also found that yellowtail juveniles frequently aggregated with drifting temperate algae from late winter to spring when drifting tropical algae were unavailable. Local fishermen collect these juveniles for use as aquaculture seed stock; therefore, the occurrence of drifting temperate algae in early spring is important for local fisheries. These results suggest that the further extinction of temperate Sargassum spp. may have negative impacts on the pelagic ecosystem and associated regional fisheries.

Assessment of the water quality parameters in relation to fish ...

African Journals Online (AJOL)

Physicochemical indices of water body changed seasonally and this necessitated an investigation to assess the water quality parameters of Osinmo reservoir in relation to its fish species. The water quality parameters were measured using standard methods. Results obtained show that the reservoir is alkaline in nature with ...

Fish elevator and method of elevating fish

Science.gov (United States)

Truebe, Jonathan; Drooker, Michael S.

1984-01-01

A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water.

Influence of Ross Sea Bottom Water changes on the warming and freshening of the Antarctic Bottom Water in the Australian-Antarctic Basin

Directory of Open Access Journals (Sweden)

K. Shimada

2012-07-01

Full Text Available Changes to the properties of Antarctic Bottom Water in the Australian-Antarctic Basin (AA-AABW between the 1990s and 2000s are documented using data from the WOCE Hydrographic Program (WHP and repeated hydrographic surveys. Strong cooling and freshening are observed on isopycnal layers denser than γⁿ = 28.30 kg m⁻³. Changes in the average salinity and potential temperature below this isopycnal correspond to a basin-wide warming of 1300 ± 200 GW and freshening of 24 ± 3 Gt year⁻¹. Recent changes to dense shelf water in the source regions in the Ross Sea and George V Land can explain the freshening of AA-AABW but not its extensive warming. An alternative mechanism for this warming is a decrease in the supply of AABW from the Ross Sea (RSBW. Hydrographic profiles between the western Ross Sea and George V Land (171–158° E were analyzed with a simple advective-diffusive model to assess the causes of the observed changes. The model suggests that the warming of RSBW observed between the 1970s and 2000s can be explained by a 21 ± 23% reduction in RSBW transport and the enhancement of the vertical diffusion of heat resulting from a 30 ± 7% weakening of the abyssal stratification. The documented freshening of Ross Sea dense shelf water leads to a reduction in both salinity and density stratification. Therefore the direct freshening of RSBW at its source also produces an indirect warming of the RSBW. A simple box model suggests that the changes in RSBW properties and volume transport (a decrease of 6.7% is assumed between the year 1995 and 2005 can explain 51 ± 6% of the warming and 84 ± 10% of the freshening observed in AA-AABW.

Larval fish variability in response to oceanographic features in a nearshore nursery area.

Science.gov (United States)

Pattrick, P; Strydom, N A

2014-09-01

The influence of oceanographic features on ichthyoplankton assemblages in the warm temperate nearshore region of Algoa Bay, South Africa, was assessed. The nearshore ichthyoplankton comprised 88 taxa from 34 families. Samples were collected at six stations between August 2010 and July 2012 using a plankton ring net of 750 mm diameter and 500 µm mesh aperture. The majority of larvae collected were in a preflexion stage, indicating the potential importance of the nearshore for newly hatched larvae. Engraulidae dominated the catch (38·4%), followed by Cynoglossidae (28·1%) and Sparidae (8·4%). Larval fish abundance was highest during austral spring and summer (September to February). Unique patterns in responses of each dominant fish species to oceanographic features in the nearshore indicate the sensitivity of the early developmental stage to environmental variables. Using generalized linear models, ichthyoplankton abundance responded positively to upwelling and when warm water plumes originating from an Agulhas Current meander entered Algoa Bay. Highest abundances of Engraulis encrasicolus and Sardinops sagax were observed during Agulhas Plume intrusions into Algoa Bay. When a mixed and stratified water column persisted in the nearshore region of Algoa Bay, larval fish abundance decreased. The nearshore region of Algoa Bay appears to serve as a favourable environment for the accumulation of ichthyoplankton. © 2014 The Fisheries Society of the British Isles.

Entrainment of ichthyoplankton and larval fishes during cooling water withdrawal

International Nuclear Information System (INIS)

McFarlane, R.W.

1978-01-01

Plantonic fish eggs and larvae are entrained into the Savannah River Plant (SRP) pumping system as Savannah River water is withdrawn for cooling purposes. The American shad contributed 96% of the planktonic fish eggs collected in the Savannah River. Eggs were rare in plankton samples from the intake canals and were assumed to have settled to the bottom as current velocity was reduced in the canal entrance. An estimated 72 million fish eggs were transported past the intake canals. Assuming ''worst case conditions,'' 6.8 million eggs (9.5%) could have been lost due to entrainment. Blueback herring comprised nearly one-half of the 216 million fish larvae susceptible to impact. Spotted sucker and black crappie were also common among the 22 species of fish larvae collected. An estimated 19.6 million (9.1%) fish larvae could have been entrained under ''worst case conditions''

Metal Distribution and Bioaccumulation in Water and Fish of a ...

African Journals Online (AJOL)

A study was conducted to investigate the metal (copper, zinc and manganese) concentrations in the surface water and fish of a man-made lake receiving agricultural and domestic effluents in Ibadan, Nigeria. The lake (Main Lake, IITA) is a site of drinking water abstraction and the major water source for the surrounding ...

Seawater/Saline Agriculture for Energy, Warming, Water, Rainfall, Land, Food and Minerals

Science.gov (United States)

Bushnell, Dennis

2006-01-01

The combination of the incipient demise of cheap oil and increasing evidence of Global Warming due to anthropogenic fossil carbon release has reinvigorated the need for and efforts on Renewable energy sources, especially for transportation applications. Biomass/Bio-diesel appears to have many benefits compared to Hydrogen, the only other major renewable transportation fuel candidate. Biomass Production is currently limited by available arable land and fresh water. Halophyte Plants and seawater irrigation proffer a wholly new biomass production mantra using wastelands and very plentiful seawater. Such an approach addresses many-to-most of the major emerging Societal Problems including Land, Water, Food, Warming and Energy. For many reasons, including seawater agriculture, portions of the Sahara appear to be viable candidates for future Biomass Production. The apparent nonlinearity between vegetation cover and atmospheric conditions over North Africa necessitates serious coupled boundary layer Meteorology and Global Circulation Modeling to ensure that this form of Terra Forming is Favorable and to avoid adverse Unintended Consequences.

Heavy metal and radioactivity measurements in fish, water, plants and soils in tin-mining pool

International Nuclear Information System (INIS)

Muhammad Samudi Yasir; Norlaili Ahmad Kabir; Redzuwan Yahaya; Amran Abdul Majid

2008-01-01

Malaysia aggressively reclaimed most of their disused tin-mining pool especially for agricultural activities, freshwater fish farming area, recreational area, houses area and even as an industrial area. Past mining activities might induced the concentration of naturally occurring radionuclide (NORM) and heavy metal at the disused tin-mining pool ecosystem. A study has been conducted on the status of heavy metal (Hf, Zr, Mn, Cu, Zn, As, Cd, Sn, Sb, Ba, Hg and Pb) concentration and naturally occurring radionuclide activity in fish, water, plants and sediments at three different disused tin-mining pool near by Sepang and Puchong, Selangor Darul Ehsan. Sample of fish, water, plant and sediment being analyze using ICP-MS. The concentrations of heavy metal in sediment and plant are higher than its concentrations in fish and followed by water. The highest concentration of heavy metal in sediment and water is barium, whereas the highest concentration of heavy metal in fish and plant is zinc and manganese. The result also showed that only mercury level in fish collected in second disused tin-mining pool (0.53 ± 0.20 mg/ kg) is exceed the maximum limit (0.5 mg/ kg) prescribe by the Malaysian Food Act (Act 281). The activity of U-238 and Th-232 in sediment was found to be relatively higher than its activity in fish, plant or water (30.76 ± 2.71 to 35.34 ± 0.27 Bq/ kg) and (9.37 ± 2.30 - 18.86 ± 2.60 Bq/ kg). The determination of K-40 activity showed that it is highly contained in plant and fish than in sediment or water. (author)

RESEARCH METHODOLOGY ON NATURAL NUTRITION OF FRESH-WATER FISH

Directory of Open Access Journals (Sweden)

Marina Piria

2001-03-01

Full Text Available This paper offers the entire review on the research methodology in natural nutrition of fresh-water fish. The data on fresh-water fish nutrition, particularly on fish of lower economic value, is inadequate. Reviewing the literature on assesment of nutritional parameters, the authors obviously use differenet approaches and methods. This paper is about most frequently used parameteres in qualitative and quantitative analysis. The qualitative analysis of food structure is the overall list of determinable taxa (mostlyu species and genera. The quantitative analysis comprises the assessment of particular nutritional categories by nutritional indices and coefficients. Bio-identification and numeric data processing can have numerous drawbacsk such as effect of regurgitation or the degree of digestion of the prey. The analyses of those effects proceed through statistical data processing in order to include spatial distribution of certain prey categories as well. The importance of this data is to determine the nutritional needs of potential species for culture as well as to come up with new insights on a particular aquatic ecosystem.

Fish elevator and method of elevating fish

Energy Technology Data Exchange (ETDEWEB)

Truebe, J.; Drooker, M.S.

1984-02-14

A means and method are disclosed for transporting fish from a lower body of water to a higher body of water. The means comprise a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water. 6 figs.

Additive and Synergistic Impacts of Fishing and Warming on the Growth of a Temperate Marine Fish

Science.gov (United States)

Morrongiello, J.

2016-02-01

Fishing and climate change are having profound impacts on the trajectory and variability of marine populations. However, despite the wealth of work undertaken in marine environments on the causes of longer-term biological change, the effects of these two drivers have traditionally been considered in isolation or just additively. Such an approach obviously overlooks the potential for significant synergistic or antagonistic interactions between fishing and climate to occur. Indeed, it is increasingly becoming acknowledged that the direction and magnitude of biological responses to natural environmental variation and climate change can be mediated by other anthropogenic disturbances such as fishing, and vice versa. Somatic growth is an ideal candidate with which to explore the impacts of fishing and environmental variability due to its strong biological relevance and its heightened sensitivity to natural and anthropogenic drivers. I developed 19-year growth biochronologies (1980-1999) for three south-east Australian populations of a site-attached temperate reef fish, purple wrasse (Notolabrus fucicola) using individual-based growth information naturally archived in otoliths. A commercial wrasse fishery began in the early 1990s; before this there was negligible recreational or commercial fishing. The growth of older fish was proportionally higher and that of the youngest fish proportionally lower after the onset of commercial fishing; 2-year olds grew 7.4% slower, but 5-year-olds grew 10.3% and 10-year-olds 26% faster in the latter period. These results are consistent with a density dependent response to harvesting. Average growth rates across all ages increased by 6.6%.oC-1, reflecting either a direct or indirect temperature effect in this global marine 'hotspot'. Finally, the distribution of individual thermal reaction norms significantly changed post fishing, showing that fishing and temperature can have a synergetic impact on marine populations via within

Contribution of water chemistry and fish condition to otolith chemistry: comparisons across salinity environments.

Science.gov (United States)

Izzo, C; Doubleday, Z A; Schultz, A G; Woodcock, S H; Gillanders, B M

2015-06-01

This study quantified the per cent contribution of water chemistry to otolith chemistry using enriched stable isotopes of strontium ((86) Sr) and barium ((137) Ba). Euryhaline barramundi Lates calcarifer, were reared in marine (salinity 40), estuarine (salinity 20) and freshwater (salinity 0) under different temperature treatments. To calculate the contribution of water to Sr and Ba in otoliths, enriched isotopes in the tank water and otoliths were quantified and fitted to isotope mixing models. Fulton's K and RNA:DNA were also measured to explore the influence of fish condition on sources of element uptake. Water was the predominant source of otolith Sr (between 65 and 99%) and Ba (between 64 and 89%) in all treatments, but contributions varied with temperature (for Ba), or interactively with temperature and salinity (for Sr). Fish condition indices were affected independently by the experimental rearing conditions, as RNA:DNA differed significantly among salinity treatments and Fulton's K was significantly different between temperature treatments. Regression analyses did not detect relations between fish condition and per cent contribution values. General linear models indicated that contributions from water chemistry to otolith chemistry were primarily influenced by temperature and secondly by fish condition, with a relatively minor influence of salinity. These results further the understanding of factors that affect otolith element uptake, highlighting the necessity to consider the influence of environment and fish condition when interpreting otolith element data to reconstruct the environmental histories of fish. © 2015 The Fisheries Society of the British Isles.

Zoogeography of the fishes from Indochinese Inland waters with an annotated check-list

NARCIS (Netherlands)

Kottelat, Maurice

1989-01-01

According to an unpublished bibliography of Indochinese freshwater fishes that I completed, 930 native fish species are known to occur in the inland waters of the Indochinese Peninsula, certainly making it one of the areas with the most diverse ichthyofauna. The study of this rich fish fauna is

Recent changes in the deep-water fish populations of Lake Michigan

Science.gov (United States)

Moffett, James W.

1957-01-01

The deep-water fish fauna of Lake Michigan consisted of lake trout (Salvelinus namaycush), burbot (Lota lota maculosa), seven species of chubs or deep-water ciscoes (Leucichthys spp.), and the deep-water sculpin (Myoxocephalus quadricornis). Other species occupied the deep-water zone but were not typically part of the fauna.

Impact of Monsoon to Aquatic Productivity and Fish Landing at Pesawaran Regency Waters

Science.gov (United States)

Kunarso; Zainuri, Muhammad; Ario, Raden; Munandar, Bayu; Prayogi, Harmon

2018-02-01

Monsoon variability influences the productivity processes in the ocean and has different responses in each waters. Furthermore, variability of marine productivity affects to the fisheries resources fluctuation. This research has conducted using descriptive method to investigate the consequences of monsoon variability to aquatic productivity, sea surface temperature (SST), fish catches, and fish season periods at Pesawaran Regency waters, Lampung. Variability of aquatic productivity was determined based on chlorophyll-a indicator from MODIS satellite images. Monsoon variability was governed based on wind parameters and fish catches from fish landing data of Pesawaran fish market. The result showed that monsoon variability had affected to aquatic productivity, SST, and fish catches at Pesawaran Regency waters. Maximum wind speed and lowest SST occurred twice in a year, December to March and August to October, which the peaks were on January (2.55 m/s of wind speed and 29.66°C of SST) and September (2.44 m/s of wind speed and 29.06°C of SST). Also, Maximum aquatic productivity happened on January to March and July to September, which it was arisen simultaneously with maximum wind speed and the peaks was 0.74 mg/m3 and 0.78 mg/m3, on February and August respectively. The data showed that fish catches decreased along with strong wind speed and low SST. However, when weak wind speed and high SST occurred, fish catches increased. The correlation between Catch per Unit Effort (CPUE) with SST, wind speed, and chlorophyll-a was at value 0.76, -0.67, and -0.70, respectively. The high rate fish catches in Pesawaran emerged on March-May and September-December.

Linking water treatment practices and fish welfare

DEFF Research Database (Denmark)

Zubiaurre, Claire; Pedersen, Lars-Flemming

2016-01-01

Peracetic acids can be used as sanitizers to control water quality in aquaculture systems. As an alternative to formalin, chloramine-T or copper sulphate, PAA has strong anti-microbial effects, degrades quickly and is relatively safe to use. Its mode of action and associated rapid decay can make....... Supportive enzymatic, biochemical and physiological biomarkers can be used along with gill and epidermal histological measures to evaluate the effects on water treatment regimens. The ultimate goal is to define the therapeutic window where fish welfare is not compromised.PAA is among the few disinfectants...

INFLUENCE OF CARP BREEDING ON PHYSICOCHEMICAL STATE OF WATER IN FISH POND AND RECEIVE

Directory of Open Access Journals (Sweden)

Włodzimierz Kanownik

2015-10-01

Full Text Available The paper presents the results of tests on quality features of feeding water and fish ponds of Mydlniki fish farm in the małopolskie province. The measurement and control points are situated in the river Rudawa before and below the farm and in four breeding ponds were measured in water: temperature, concentrations of dissolved oxygen, electrolytic conductivity, pH, total suspended solids, dissolved solids and concentrations of minerals: SO42+, Cl-, Ca2+, Mg2+, Na+, K+, Fe i Mn, and also biogenic compounds (PO43-, N-NH4+, N-NO2-, N-NO3-. It was found that water from the Rudawa river feeding the ponds did not meet the requirements for inland waters which are the natural environment for the cyprinids. The physicochemical state is below the well due to the high concentration of phosphate. Statistical analysis of 19 tested features revealed a positive effect of the fish ponds on water quality. Concentrations of biogenic compounds (phosphate, nitrite and nitrate nitrogen, dissolved solids, calcium and water conductivity in the fish ponds decreased on average by between 30 and 87% in comparison with the feeding watercourse.

A cascade of warming impacts brings bluefin tuna to Greenland waters

DEFF Research Database (Denmark)

MacKenzie, Brian R.; Payne, Mark R.; Boje, Jesper

2014-01-01

Rising ocean temperatures are causing marine fish species to shift spatial distributions and ranges, and are altering predator-prey dynamics in food webs. Most documented cases of species shifts so far involve relatively small species at lower trophic levels, and consider individual species in ec...... impacts is restructuring the food web in east Greenland waters.......Rising ocean temperatures are causing marine fish species to shift spatial distributions and ranges, and are altering predator-prey dynamics in food webs. Most documented cases of species shifts so far involve relatively small species at lower trophic levels, and consider individual species...

Detection of Flavobacterium psychrophilum from fish tissue and water samples by PCR amplification

DEFF Research Database (Denmark)

Wiklund, T.; Madsen, Lone; Bruun, Morten Sichlau

2000-01-01

investigation, the possible detection of Fl. psychrophilum from fish tissue and water samples was examined using nested PCR with DNA probes against a sequence of the 16S rRNA genes. The DNA was extracted using Chelex(R) 100 chelating resin. The primers, which were tested against strains isolated from diseased...... fish, healthy fish, fish farm environments and reference strains, proved to be specific for Fl. psychrophilum. The obtained detection limit of Fl. psychrophilum seeded into rainbow trout brain tissue was 0.4 cfu in the PCR tube, corresponding to 17 cfu mg(-1) brain tissue. The PCR-assay proved...... to be more sensitive than agar cultivation of tissue samples from the brain of rainbow trout injected with Fl. psychrophilum. In non-sterile fresh water seeded with Fl. psychrophilum the detection limit of the PCR- assay was 1.7 cfu in the PCR tube, corresponding to 110 cfu ml(-1) water. The PCR...

Fish Mercury and Surface Water Sulfate Relationships in the Everglades Protection Area

Science.gov (United States)

Few published studies present data on relationships between fish mercury and surface or pore water sulfate concentrations, particularly on an ecosystem-wide basis. Resource managers can use these relationships to identify the sulfate conditions that contain fish with health-conce...

Fish-protection devices at unscreened water diversions can reduce entrainment: evidence from behavioural laboratory investigations

Science.gov (United States)

Poletto, Jamilynn B.; Cocherell, Dennis E.; Mussen, Timothy D.; Ercan, Ali; Bandeh, Hossein; Kavvas, M. Levent; Cech, Joseph J.; Fangue, Nann A.

2015-01-01

Diversion (i.e. extraction) of water from rivers and estuaries can potentially affect native wildlife populations if operation is not carefully managed. For example, open, unmodified water diversions can act as a source of injury or mortality to resident or migratory fishes from entrainment and impingement, and can cause habitat degradation and fragmentation. Fish-protection devices, such as exclusion screens, louvres or sensory deterrents, can physically or behaviourally deter fish from approaching or being entrained into water diversions. However, empirical assessment of their efficacy is often lacking or is investigated only for particular economically or culturally important fishes, such as salmonids. The Southern population of anadromous green sturgeon (Acipenser medirostris) is listed as threatened in California, and there is a high density of water diversions located within their native range (the Sacramento–San Joaquin watershed). Coupled with their unique physiology and behaviour compared with many other fishes native to California, the green sturgeon is susceptible to entrainment into diversions and is an ideal species with which to study the efficacy of mitigation techniques. Therefore, we investigated juvenile green sturgeon (188–202 days post-hatch) in the presence of several fish-protection devices to assess behaviour and entrainment risk. Using a large experimental flume (∼500 kl), we found that compared with an open diversion pipe (control), the addition of a trash-rack box, louvre box, or perforated cylinder on the pipe inlet all significantly reduced the proportion of fish that were entrained through the pipe (P = 0.03, P = 0.028, and P = 0.028, respectively). Likewise, these devices decreased entrainment risk during a single movement past the pipe by between 60 and 96%. These fish-protection devices should decrease the risk of fish entrainment during water-diversion activities. PMID:27293725

Influence of water temperature on the economic value of growth rate in fish farming

NARCIS (Netherlands)

Besson, M.; Vandeputte, M.; Arendonk, van J.A.M.; Aubin, J.; Boer, de I.J.M.; Quillet, E.; Komen, H.

2016-01-01

In sea cage farming, fish are exposed to seasonal variations of water temperature, and these variations can differ from one location to another. A small increase in water temperature does not only stimulate growth of the fish (until an optimal level) but also lowers dissolved oxygen concentration

Impact of treated wastewater reuse and floods on water quality and fish health within a water reservoir in an arid climate.

Science.gov (United States)

Zaibel, Inbal; Zilberg, Dina; Groisman, Ludmila; Arnon, Shai

2016-07-15

Treated wastewater (TWW) reuse for agricultural irrigation is a well-established approach to coping with water shortages in semi-arid and arid environments. Recently, additional uses of TWW have emerged, including streamflow augmentation and aquatic ecosystem restoration. The purpose of the current study was to evaluate the water quality and fish health, in an artificial reservoir located in an arid climate (the Yeruham Reservoir, Israel), which regularly receives TWW and sporadic winter floods. The temporal distribution of water levels, nutrients and organic micropollutants (OMPs) were measured during the years 2013-2014. OMPs were also measured in sediment and fish tissues. Finally, the status of fish health was evaluated by histopathology. Water levels and quality were mainly influenced by seasonal processes such as floods and evaporation, and not by the discharge of TWW. Out of 16 tested OMPs, estrone, carbamazepine, diclofenac and bezafibrate were found in the reservoir water, but mostly at concentrations below the predicted no-effect concentration (PNEC) for fish. Concentrations of PCBs and dioxins in fish muscle and liver were much lower than the EU maximal permitted concentrations, and similar to concentrations that were found in food fish in Israel and Europe. In the histopathological analysis, there were no evident tissue abnormalities, and low to moderate infection levels of fish parasites were recorded. The results from the Yeruham Reservoir demonstrated a unique model for the mixture effect between TWW reuse and natural floods to support a unique stable and thriving ecosystem in a water reservoir located in an arid region. This type of reservoir can be widely used for recreation, education, and the social and economic development of a rural environment, such as has occurred in the Yeruham region. Copyright © 2016 Elsevier B.V. All rights reserved.

The co-distribution of seabirds and their juvenile fish prey in Baffin Bay

DEFF Research Database (Denmark)

LeBlanc, Mathieu; Mosbech, Anders; Fortier, Louis

documented. We test the hypothesis that the abundance and biomass of juvenile fish, especially at the sea-ice edge, influence the distribution and composition of the seabird assemblage. Hydroacoustic data were recorded continuously during the CCGS Amundsen GreenEdge 2016 cruise in southern Baffin Bay, using...... cod (Boreogadus saida), the main pelagic forage fish, plays a key role by transferring energy from the zooplankton to the upper trophic levels, including seabirds. The interactions between fish and seabirds at the sea-ice edge, an environment increasingly common in the warming Arctic, are poorly...... a hull-mounted EK60 multi-frequency echosounder. Pelagic nets were deployed to document the fish assemblage and to validate the acoustic echoes. Seabird observations during transit periods and seabird sampling in Greenland waters were completed. This study will provide insights in the predator...

A middle Pleistocene eastern Mediterranean fish refuge: the Tsampika Bay (Rhodes, Greece)

Science.gov (United States)

Agiadi, K.; Koskeridou, E.; Moissette, P.; Lopez-Otalvaro, G. E.; Quillévéré, F.; Cornée, J. J.

2012-04-01

Extensive sampling of the Tsampika marly diatomites reveals the presence of at least three very important fish species, Bregmaceros sp., Sygnathus acus and Spratteloides sp.. Previous records of Bregmaceros sp. in the Mediterranean have suggested that this characteristic Pliocene warm-water circumglobal pelagic fish disappeared from the Mediterranean basin due to the climatic deterioration, after the Gelasian age1,2,3,4. The Tsampika fish-bearing deposits, mainly marly diatomites, are younger than 268 Ka, based on the occurrence of Emiliania huxleyi. Consequently, this is so far the youngest record of Bregmaceros sp. in the Mediterranean, suggesting that typical Pliocene fish may have found refuge in selected localities, such as Tsampika Bay, at least until the Ionian. Evidence for its presence in the Mediterranean basin today is ambiguous. Isolated records of Bregmaceros atlanticus place it in the Sicily Strait5, and off the Israeli and south Turkish coasts6. Although it appears more likely that Bregmaceros atlanticus has been introduced to the modern Mediterranean from the Red Sea, through the Suez Canal, the possibility that it is part of a small population native to the Mediterranean can not be excluded based on present-day data6. Indeed the late Pleistocene Mediterranean fish record is obsolete, due to the lack of appropriate sampling on this subject. Furthermore, the majority of Pleistocene Bregmaceros samples pertain to otoliths, which cannot be unambiguously identified on the species level. As a result, the present findings pose the considerable possibility that the Pleistocene Bregmaceros records belong to two species, B. albyi, the well known post-Messinian Mediterranean fish, and B. atlanticus, which may have invaded the Mediterranean Sea from Gibraltar along with several other warm-water taxa during recurring interglacial periods. The specific identification of the Tsampika fish will undoubtedly shed light to this possibility, and enhance our knowledge

Warm versus Cold Water Island Tourism: A Review of Policy Implications

Directory of Open Access Journals (Sweden)

Godfrey Baldacchino

2006-11-01

Full Text Available Not sun, sea, sand but ice, isolation, indigenous people: the critical exploration of extreme tourism in cold water locations has barely started. Cold water island locations tend to have harsh, pristine and fragile natural environments, characterized by wide open spaces. They become contexts for an exceptional and expensive form of vigorous, outdoor, adventure or cultural tourism, and direct encounters with nature. The nature and practices of the tourism industry suggest a more sustainable form of island tourism, very different from what is experienced on the warm, tropical and exotic island stereotype.This paper critically reviews some of the salient contrasts between the ‘hot’ and ‘cold’ versions of island tourism. It discusses how, on many ‘cold water’ island locations, sound strategic management, limited civilian ‘buy in’, low populations and an absence of pluralism in political life, can conspire with climate and relative inaccessibility to limit tourism to a small scale, low-impact industry with a relatively high, locally-retained value added. Some ‘warm water’ islands are trying to follow this model for tourism development, with mixed results.

Grey mullet (Mugilidae) as possible indicators of global warming in South African estuaries and coastal waters.

Science.gov (United States)

James, Nicola C; Whitfield, Alan K; Harrison, Trevor D

2016-12-01

The grey mullet usually occur in large numbers and biomass in the estuaries of all three South African biogeographic regions, thus making it an ideal family to use in terms of possibly acting as an environmental indicator of global warming. In this analysis the relative estuarine abundance of the dominant three groups of mugilids, namely tropical, warm-water and cool-water endemics, were related to sea surface coastal temperatures. The study suggests a strong link between temperature and the distribution and abundance of the three mullet groups within estuaries and indicates the potential of this family to act as an indicator for future climate change within these systems and adjacent coastal waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

Studies of trace metals in fish, sediment and water from kpong reservior

International Nuclear Information System (INIS)

Yikpo, Wisdom Kwasi

2014-06-01

Water of good quality is indispensable to human survival on earth. The provision of potable water to both the rural and the urban populations is necessary to prevent health hazards. The aim of this research was to assess water quality with respect to physicochemical parameters and trace metals levels in the water, the sediment and the fish species from the Kpong Reservoir on the Lower Volta River. The water, the sediment and the fish samples were collected monthly for six (6) months from November 2011 to February 2012 (dry season) and from May to July 2012 ( wet season). The water, the sediment and the fish samples were analyzed for Hg, Se, Fe, Mn and Pb using Atomic Absorption spectroscopy (AAS). Mercury was determined using a cold vapour technique with the AAS equipped with a hydride generator. Selenium was also determined by hydride generation. A mixture of nitric acid (HNO3 65%), hydrochloric acid ( HCl 35%) and hydrogen peroxide (H2O2 30%) was used for complete oxidation of the organic sample in a fume chamber. The samples were loaded on a Milestone microwave Labstation ETHOS 900, INSTR:MLS -1200 MEGA. The results of this study showed that there were significant differences in concentrations of the physicochemical parameters between the two seasons. Domestic, municipal and Agricultural waste might have contributed to the release of higher contaminants into the sediment in both seasons. Coefficients of variation for the physicochemical parameters were below 50%, while iron and lead in addition to phosphate and sulphate were more than 50%. The mean concentration of trace metals in the water were 0.008 mg/L for Hg, 0.0035 mg/L for Se, 0.255 mg/L for Fe, 0.087 mg/L for Mn and 0.135 mg/L for Pb. Levels of all trace metals were below the WHO guideline values, except Pb which exceeded at 0.05 mg/L. Levels of nutrients were also below the WHO guideline value except phosphate which recorded a standard deviation of ±0.02 for the WHO guideline value of 0.3 mg/ L. The

RA-226 concentration in water samples near uranium mines and in marine fishes

International Nuclear Information System (INIS)

Porntepkasemsan, B.

1987-11-01

Radium-226 and calcium were measured in water samples from the vicinity of three uranium mines and in fish samples collected from Puget sound, Washington State. The radium content of the samples were below the maximum permissible concentration 3 pCi/L for drinking water recommended by the Public Health Service and U.S. Environmental Protection Agency. The mean value of Ra-226 in water was 0.428 pCi/L and ranged from 0.043 to 1.552 pCi/L, whereas calcium content ranged from 3.0 to 190.0 mg/L. Ra-226 concentrations and calcium content in whole fish were 0.833-20.328 pCi/kg wet wt. and 114.1-259.3 mg/g ash, respectively. Results of the study indicated that Ra-226 concentration in water was correlated with calcium concentration but that this correlation was not observed in fish sample except English sole

Water- and plant-mediated responses of ecosystem carbon fluxes to warming and nitrogen addition on the Songnen grassland in northeast China.

Directory of Open Access Journals (Sweden)

Li Jiang

Full Text Available Understanding how grasslands are affected by a long-term increase in temperature is crucial to predict the future impact of global climate change on terrestrial ecosystems. Additionally, it is not clear how the effects of global warming on grassland productivity are going to be altered by increased N deposition and N addition.In-situ canopy CO(2 exchange rates were measured in a meadow steppe subjected to 4-year warming and nitrogen addition treatments. Warming treatment reduced net ecosystem CO(2 exchange (NEE and increased ecosystem respiration (ER; but had no significant impacts on gross ecosystem productivity (GEP. N addition increased NEE, ER and GEP. However, there were no significant interactions between N addition and warming. The variation of NEE during the four experimental years was correlated with soil water content, particularly during early spring, suggesting that water availability is a primary driver of carbon fluxes in the studied semi-arid grassland.Ecosystem carbon fluxes in grassland ecosystems are sensitive to warming and N addition. In the studied water-limited grassland, both warming and N addition influence ecosystem carbon fluxes by affecting water availability, which is the primary driver in many arid and semiarid ecosystems. It remains unknown to what extent the long-term N addition would affect the turn-over of soil organic matter and the C sink size of this grassland.

Fish and robots swimming together in a water tunnel: robot color and tail-beat frequency influence fish behavior.

Directory of Open Access Journals (Sweden)

Giovanni Polverino

Full Text Available The possibility of integrating bioinspired robots in groups of live social animals may constitute a valuable tool to study the basis of social behavior and uncover the fundamental determinants of animal functions and dysfunctions. In this study, we investigate the interactions between individual golden shiners (Notemigonus crysoleucas and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish positional preference with respect to the robot is experimentally analyzed as the robot's color pattern and tail-beat frequency are varied. Behavioral observations are corroborated by particle image velocimetry studies aimed at investigating the flow structure behind the robotic fish. Experimental results show that the time spent by golden shiners in the vicinity of the bioinspired robotic fish is the highest when the robot mimics their natural color pattern and beats its tail at the same frequency. In these conditions, fish tend to swim at the same depth of the robotic fish, where the wake from the robotic fish is stronger and hydrodynamic return is most likely to be effective.

Fish and robots swimming together in a water tunnel: robot color and tail-beat frequency influence fish behavior.

Science.gov (United States)

Polverino, Giovanni; Phamduy, Paul; Porfiri, Maurizio

2013-01-01

The possibility of integrating bioinspired robots in groups of live social animals may constitute a valuable tool to study the basis of social behavior and uncover the fundamental determinants of animal functions and dysfunctions. In this study, we investigate the interactions between individual golden shiners (Notemigonus crysoleucas) and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish positional preference with respect to the robot is experimentally analyzed as the robot's color pattern and tail-beat frequency are varied. Behavioral observations are corroborated by particle image velocimetry studies aimed at investigating the flow structure behind the robotic fish. Experimental results show that the time spent by golden shiners in the vicinity of the bioinspired robotic fish is the highest when the robot mimics their natural color pattern and beats its tail at the same frequency. In these conditions, fish tend to swim at the same depth of the robotic fish, where the wake from the robotic fish is stronger and hydrodynamic return is most likely to be effective.

Response of bean cultures' water use efficiency against climate warming in semiarid regions of China.

Science.gov (United States)

Guoju, Xiao; Fengju, Zhang; Juying, Huang; Chengke, Luo; Jing, Wang; Fei, Ma; Yubi, Yao; Runyuan, Wang; Zhengji, Qiu

2016-07-31

Farm crop growing and high efficiency water resource utilizing are directly influenced by global warming, and a new challenge will be given to food and water resource security. A simulation experiment by farm warming with infrared ray radiator was carried out, and the result showed photosynthesis of broad bean was significantly faster than transpiration during the seedling stage, ramifying stage, budding stage, blooming stage and podding stage when the temperate was increased by 0.5-1.5 °C. But broad bean transpiration was faster than photosynthesis during the budding stage, blooming stage and podding stage when the temperature was increased by 1.5 °C above. The number of grain per hill and hundred-grain weight were significantly increased when the temperature was increased by 0.5-1.0 °C. But they significantly dropped and finally the yield decreased when the temperature was increased by 1.0 °C above. The broad bean yield decreased by 39.2-88.4% when the temperature was increased by 1.5-2.0 °C. The broad bean water use efficiency increased and then decreased with temperature rising. The water use efficiency increased when the temperature was increased by 1.0 °C below, and it quickly decreased when the temperature was increased by 1.0 °C above. In all, global warming in the future will significantly influence the growth, yield and water use efficiency of bean cultures in China's semiarid regions.

Prevalence of Clonorchis sinensis Metacercariae in Fish from Water Systems of Seomjin-gang (River).

Science.gov (United States)

Sohn, Woon-Mok; Na, Byoung-Kuk; Cho, Shin-Hyeong; Park, Mi-Yeoun; Kim, Cheon-Hyeon; Hwang, Min-Ah; No, Kyeong-Woo; Yoon, Ki-Bok; Lim, Hyun-Cheol

2017-06-01

The prevalence of Clonorchis sinensis metacercariae ( Cs Mc) was examined in freshwater fish from the water systems of Seomjin-gang (River), the Republic of Korea. Total 1,604 fish from 7 local sites of Seomjin-gang were examined by artificial digestion methods. The metacercariae of C. sinensis were detected in 102 (39.8%) out of 256 fish (14 species) from the upper reaches of Seomjin-gang, i.e., Osucheon (22.3% in 6 fish species) in Imsil-gun, and Seomjin-gang (63.9% in 9 fish species) in Sunchang-gun, Jeollabuk-do. Their average density was 9.0 per infected fish. They were also found in 132 (48.0%) out of 275 fish (12 spp.) from the middle reaches of Seomjin-gang, i.e., Songdaecheon (58.9% in 4 fish species) in Namwon-si, Jeollabuk-do, and Seomjin-gang (45.2% in 10 fish species) in Gokseong-gun, Jeollanam-do. Their average density was 21.0 per infected fish. Cs Mc were detected in 77 (56.6%) out of 136 fish (11 species) from the lower reaches of Seomjin-gang, i.e., Seomjin-gang (73.3% in 11 fish species) in Gurye-gun, Jeollanam-do, and Namsancheon (8.6% in 1 fish species) in Hadong-gun, Gyeongsangnam-do. Their average density was 64.9 per infected fish. The metacercariae of Metorchis orientalis were also detected in 6 fish species from 4 sites of Seomjin-gang. Conclusively, it has been confirmed that Cs Mc are more or less prevalent in fish from some water systems of Seomjin-gang in Korea.

Selenium and other elements in freshwater fishes from the irrigated San Joaquin Valley, California

Science.gov (United States)

Saiki, M.K.; Jennings, M.R.; May, T.W.

1992-01-01

Arsenic (As), chromium (Cr), mercury (Hg), and selenium (Se) were measured in composite whole-body samples of five fishes — bluegill (Lepomis macrochirus), common carp (Cyprinus carpio), mosquitofish (Gambusia affinis), largemouth bass (Micropterus salmoides), and Sacramento blackfish (Orthodon microlepidotus) — from the San Joaquin River system to determine if concentrations were elevated from exposure to agricultural subsurface (tile) drainage. Except for Cr, the concentrations of these elements in fishes from one or more sites were elevated; however, only Se approached concentrations that may adversely affect survival, growth, or reproduction in warm water fishes. Moreover, only Se among the four measured elements exhibited a geographic (spatial) pattern that coincided with known inflows of tile drainage to the San Joaquin River and its tributaries. Historical data from the Grassland Water District (Grasslands; a region exposed to concentrated tile drainage) suggested that concentrations of Se in fishes were at maximum during or shortly after 1984 and have been slightly lower since then. The recent decline of Se concentrations in fishes from the Grasslands could be temporary if additional acreages of irrigated lands in this portion of the San Joaquin Valley must be tile-drained to protect agricultural crops from rising groundwater tables.

Microbiological spoilage of fish and fish products

DEFF Research Database (Denmark)

Gram, Lone; Huss, Hans Henrik

1996-01-01

Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative...... biochemical indicators of spoilage. Shewanzella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram......- positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish...

Economic differential of integrated fish, rice cum piggery and fish ...

African Journals Online (AJOL)

Fish, rice cum piggery and fish, rice cum poultry production integration platforms were set up to perfect the ideas of integrated fish farming in Sierra Leone. Water quality parameters measured biweekly included: dissolved oxygen, water temperature, pH, water hardness, water alkalinity, ammonia, nitrate, BOD and nitrite.

Decadal-scale variation in diet forecasts persistently poor breeding under ocean warming in a tropical seabird.

Science.gov (United States)

Tompkins, Emily M; Townsend, Howard M; Anderson, David J

2017-01-01

Climate change effects on population dynamics of natural populations are well documented at higher latitudes, where relatively rapid warming illuminates cause-effect relationships, but not in the tropics and especially the marine tropics, where warming has been slow. Here we forecast the indirect effect of ocean warming on a top predator, Nazca boobies in the equatorial Galápagos Islands, where rising water temperature is expected to exceed the upper thermal tolerance of a key prey item in the future, severely reducing its availability within the boobies' foraging envelope. From 1983 to 1997 boobies ate mostly sardines, a densely aggregated, highly nutritious food. From 1997 until the present, flying fish, a lower quality food, replaced sardines. Breeding success under the poor diet fell dramatically, causing the population growth rate to fall below 1, indicating a shrinking population. Population growth may not recover: rapid future warming is predicted around Galápagos, usually exceeding the upper lethal temperature and maximum spawning temperature of sardines within 100 years, displacing them permanently from the boobies' island-constrained foraging range. This provides rare evidence of the effect of ocean warming on a tropical marine vertebrate.

Decadal-scale variation in diet forecasts persistently poor breeding under ocean warming in a tropical seabird.

Directory of Open Access Journals (Sweden)

Emily M Tompkins

Full Text Available Climate change effects on population dynamics of natural populations are well documented at higher latitudes, where relatively rapid warming illuminates cause-effect relationships, but not in the tropics and especially the marine tropics, where warming has been slow. Here we forecast the indirect effect of ocean warming on a top predator, Nazca boobies in the equatorial Galápagos Islands, where rising water temperature is expected to exceed the upper thermal tolerance of a key prey item in the future, severely reducing its availability within the boobies' foraging envelope. From 1983 to 1997 boobies ate mostly sardines, a densely aggregated, highly nutritious food. From 1997 until the present, flying fish, a lower quality food, replaced sardines. Breeding success under the poor diet fell dramatically, causing the population growth rate to fall below 1, indicating a shrinking population. Population growth may not recover: rapid future warming is predicted around Galápagos, usually exceeding the upper lethal temperature and maximum spawning temperature of sardines within 100 years, displacing them permanently from the boobies' island-constrained foraging range. This provides rare evidence of the effect of ocean warming on a tropical marine vertebrate.

Temperature-induced water stress in high-latitude forests in response to natural and anthropogenic warming.

Science.gov (United States)

Trahan, Matthew W; Schubert, Brian A

2016-02-01

The Arctic is particularly sensitive to climate change, but the independent effects of increasing atmospheric CO2 concentration (pCO2 ) and temperature on high-latitude forests are poorly understood. Here, we present a new, annually resolved record of stable carbon isotope (δ(13) C) data determined from Larix cajanderi tree cores collected from far northeastern Siberia in order to investigate the physiological response of these trees to regional warming. The tree-ring record, which extends from 1912 through 1961 (50 years), targets early twentieth-century warming (ETCW), a natural warming event in the 1920s to 1940s that was limited to Northern hemisphere high latitudes. Our data show that net carbon isotope fractionation (Δ(13) C), decreased by 1.7‰ across the ETCW, which is consistent with increased water stress in response to climate warming and dryer soils. To investigate whether this signal is present across the northern boreal forest, we compiled published carbon isotope data from 14 high-latitude sites within Europe, Asia, and North America. The resulting dataset covered the entire twentieth century and spanned both natural ETCW and anthropogenic Late Twentieth-Century Warming (~0.7 °C per decade). After correcting for a ~1‰ increase in Δ(13) C in response to twentieth century pCO2 rise, a significant negative relationship (r = -0.53, P forests across the twentieth century, of which approximately half is attributed to a decrease in stomatal conductance in order to conserve water in response to drying conditions, with the other half being attributed to increasing pCO2 . We conclude that annual tree-ring records from northern high-latitude forests record the effects of climate warming and pCO2 rise across the twentieth century. © 2015 John Wiley & Sons Ltd.

Is This the Only Hope for Reversing Global Warming? Transitioning Each Country's All-Purpose Energy to 100% Electricity Powered by Wind, Water, and Solar

Science.gov (United States)

Jacobson, M. Z.

2016-12-01

Global warming, air pollution, and energy insecurity are three of the most significant problems facing the world today. Can these problems be solved with existing technologies implemented on a large scale or do we need to wait for a miracle technology? This talk discusses the development of technical and economic plans to convert the energy infrastructure of each of 139 countries of the world to those powered by 100% wind, water, and sunlight (WWS) for all purposes using existing technology along with efficiency measures. All purposes includes electricity, transportation, heating/cooling, industry, and agriculture/forestry/fishing. The roadmaps propose using existing WWS generator technologies along with existing electrical transportation, heating/cooling, and industrial devices and appliances, plus existing electricity storage technologies, (CSP with storage, pumped hydroelectric storage, and existing hydroelectric power) and existing heat/cold storage technologies (water, ice, and rocks) for the transitions. They envision 80% conversion to WWS by 2030 and 100% by 2050. WWS not only replaces business-as-usual (BAU) power, but also reduces 2050 BAU demand due to the higher work to energy ratio of WWS electricity over combustion, the elimination of energy for mining, transporting, and processing fuels, and improvements in end-use efficiency beyond BAU. The study examines job creation versus loss, land use requirements, air pollution mortality and morbidity cost differences, and global warming cost differences due to the conversion in each country. Results suggest that implementing these roadmaps will stabilize energy prices because fuel costs are zero; reduce international conflict by creating energy-independent countries; reduce energy poverty; reduce power disruption by decentralizing power; and avoid exploding CO2 levels. Thus, the study concludes that a 100% WWS transition provides at least one solution to global warming Please see http

Concentration of arsenic in water, sediments and fish species from naturally contaminated rivers.

Science.gov (United States)

Rosso, Juan José; Schenone, Nahuel F; Pérez Carrera, Alejo; Fernández Cirelli, Alicia

2013-04-01

Arsenic (As) may occur in surface freshwater ecosystems as a consequence of both natural contamination and anthropogenic activities. In this paper, As concentrations in muscle samples of 10 fish species, sediments and surface water from three naturally contaminated rivers in a central region of Argentina are reported. The study area is one of the largest regions in the world with high As concentrations in groundwater. However, information of As in freshwater ecosystems and associated biota is scarce. An extensive spatial variability of As concentrations in water and sediments of sampled ecosystems was observed. Geochemical indices indicated that sediments ranged from mostly unpolluted to strongly polluted. The concentration of As in sediments averaged 6.58 μg/g ranging from 0.23 to 59.53 μg/g. Arsenic in sediments barely followed (r = 0.361; p = 0.118) the level of contamination of water. All rivers showed high concentrations of As in surface waters, ranging from 55 to 195 μg/L. The average concentration of As in fish was 1.76 μg/g. The level of contamination with As differed significantly between species. Moreover, the level of bioaccumulation of As in fish species related to the concentration of As in water and sediments also differed between species. Whilst some fish species seemed to be able to regulate the uptake of this metalloid, the concentration of As in the large catfish Rhamdia quelen mostly followed the concentration of As in abiotic compartments. The erratic pattern of As concentrations in fish and sediments regardless of the invariable high levels in surface waters suggests the existence of complex biogeochemical processes behind the distribution patterns of As in these naturally contaminated ecosystems.

The influence of Pacific Equatorial Water on fish diversity in the southern California Current System

Science.gov (United States)

McClatchie, Sam; Thompson, Andrew R.; Alin, Simone R.; Siedlecki, Samantha; Watson, William; Bograd, Steven J.

2016-08-01

The California Undercurrent transports Pacific Equatorial Water (PEW) into the Southern California Bight from the eastern tropical Pacific Ocean. PEW is characterized by higher temperatures and salinities, with lower pH, representing a source of potentially corrosive (aragonite,Ωaragonite saturation with depth. Although there is substantial variability in PEW presence as measured by spice on the 26.25-26.75 isopycnal layer, as well as in pH and aragonite saturation, we found fish diversity to be stable over the decades 1985-1996 and 1999-2011. We detected significant difference in species structure during the 1998 La Niña period, due to reduced species evenness. Species richness due to rare species was higher during the 1997/1998 El Niño compared to the La Niña but the effect on species structure was undetectable. Lack of difference in the species abundance structure in the decade before and after the 1997/1999 ENSO event showed that the assemblage reverted to its former structure following the ENSO perturbation, indicating resilience. While the interdecadal species structure remained stable, the long tail of the distributions shows that species richness increased between the decades consistent with intrusion of warm water with more diverse assemblages into the southern California region.

A new signal development process and sound system for diverting fish from water intakes

International Nuclear Information System (INIS)

Klinet, D.A.; Loeffelman, P.H.; van Hassel, J.H.

1992-01-01

This paper reports that American Electric Power Service Corporation has explored the feasibility of using a patented signal development process and underwater sound system to divert fish away from water intake areas. The effect of water intakes on fish is being closely scrutinized as hydropower projects are re-licensed. The overall goal of this four-year research project was to develop an underwater guidance system which is biologically effective, reliable and cost-effective compared to other proposed methods of diversion, such as physical screens. Because different fish species have various listening ranges, it was essential to the success of this experiment that the sound system have a great amount of flexibility. Assuming a fish's sounds are heard by the same kind of fish, it was necessary to develop a procedure and acquire instrumentation to properly analyze the sounds that the target fish species create to communicate and any artificial signals being generated for diversion

Bottom trawl assessment of Lake Ontario prey fishes

Science.gov (United States)

Weidel, Brian C.; Connerton, Michael J.; Holden, Jeremy

2018-01-01

Managing Lake Ontario fisheries in an ecosystem-context requires prey fish community and population data. Since 1978, multiple annual bottom trawl surveys have quantified prey fish dynamics to inform management relative to published Fish Community Objectives. In 2017, two whole-lake surveys collected 341 bottom trawls (spring: 204, fall: 137), at depths from 8-225m, and captured 751,350 fish from 29 species. Alewife were 90% of the total fish catch while Deepwater Sculpin, Round Goby, and Rainbow Smelt comprised the majority of the remaining total catch (3.8, 3.1, and 1.1% respectively). The adult Alewife abundance index for US waters increased in 2017 relative to 2016, however the index for Canadian waters declined. Adult Alewife condition, assessed by the predicted weight of a 165 mm fish (6.5 inches), declined in 2017 from record high values observed in spring 2016. Spring 2017 Alewife condition was slightly less than the 10-year average, but the fall value was well below the 10-year average, likely due to increased Age-1 Alewife abundance. The Age-1 Alewife abundance index was the highest observed in 40 years, and 8-times higher than the previous year. The Age-1 index estimates Alewife reproductive success the preceding year. The warm summer and winter of 2016 likely contributed to the large year class. In contrast the relatively cool 2017 spring and cold winter may result in a lower than average 2017 year class. Abundance indices for Rainbow Smelt, Cisco, and Emerald Shiner either declined or remained at low levels in 2017. Pelagic prey fish diversity continues to be low since a single species, Alewife, dominates the catch. Deepwater Sculpin were the most abundant benthic prey fish in 2017 because Round Goby abundance declined sharply from 2016. Slimy Sculpin density continued to decline and the 2017 biomass index for US waters was the lowest ever observed. Prior to Round Goby proliferation, juvenile Slimy Sculpin comprised ~10% of the Slimy Sculpin catch, but

Microbial abundance and diversity in water, and immune parameters of red tilapia reared in bioflocs system with different fish density (25 fish/m3, 50 fish/m3, and 100 fish/m3

Directory of Open Access Journals (Sweden)

Frid Agustinus

2010-07-01

Full Text Available ABSTRACTThe objective of this experiment was to study microbial abundance and diversity in the water, and immune parameters of red tilapia Oreochromis sp. cultured in bioflok system with different fish stocking densities. The experiment comprised of two different factors, carbon source addition (bioflocs and control, and fish stocking density (25 fish/m3, 50 fish/m3, dan 100 fish/m3, with an experimental period of 99 days. Microbial load in water was determined biweekly, whereas immune parameters represented by fish blood profile were measured on day 0, 50, and 90. There was no significant difference in total bacteria count in the water of all treatments; there was however a tendency shown by all treatments that the microbial load in water increased along with the culture period. There were 4 genera of bacteria which particularly found in bioflok system, which are Acinetobacter sp., Corynobacterium sp., Listeria sp., dan Pseudomonas sp, and are suggested to play a role in bioflok formation. The percentage of phagocytic index of fish in bioflok system was higher than that in control, and may indicate that bioflok may stimulate the fish immune system.Keywords: bioflocs, red tilapia, bacteria, blood profile. ABSTRAKPenelitian ini bertujuan untuk mengidentifikasi kelimpahan dan keragaman jenis bakteri dalam air dan parameter imunitas ikan nila Oreochromis sp. yang dipelihara dalam sistem bioflok dengan kepadatan ikan yang berbeda. Penelitian terdiri atas dua faktor perlakuan yaitu penambahan sumber carbon (bioflok dan kontrol, dan padat penebaran ikan (25 ekor/m3, 50 ekor/m3, dan 100 ekor/m3 dengan lama waktu pemeliharaan ikan selama 99 hari. Kelimpahan bakteri diukur setiap 2 minggu sekali selama masa pemeliharaan. Parameter imunitas meliputi gambaran darah diukur dengan pengambilan contoh darah yang dilakukan pada tiga ekor ikan pada hari ke 0, 50, dan 99. Kelimpahan bakteri pada semua perlakuan pada setiap titik pengamatan tidak menunjukkan

Review of fish diversity in the Lake Huron basin

Science.gov (United States)

Roseman, E.F.; Schaeffer, J.S.; Steen, P.J.

2009-01-01

Lake Huron has a rich aquatic habitat diversity that includes shallow embayments, numerous tributaries, shallow mid-lake reef complexes, archipelagos, and profundal regions. These habitats provide support for warm, cool, and cold water fish communities. Diversity of fishes in Lake Huron reflects post-glaciation colonization events, current climate conditions, accidental and intentional introductions of non-indigenous species, and extinctions. Most extinction events have been largely associated with habitat alterations, exploitation of fisheries, and interactions with non-indigenous species. The most recent historical survey of extirpated and imperiled species conducted in the late 1970s identified 79 fish species in Lake Huron proper and about 50 additional species in tributaries. Of those 129 species, 20 are now considered extirpated or imperiled. Extirpated species include Arctic grayling, paddlefish, weed shiner, deepwater cisco, blackfin cisco, shortnose cisco, and kiyi. Six species have declined appreciably due to loss of clear-water stream habitat: the river redhorse, river darter, black redhorse, pugnose shiner, lake chubsucker, redside dace, eastern sand darter, and channel darter. While numerous agencies, universities, and other organizations routinely monitor nearshore and offshore fish distribution and abundance, there is a need for more rigorous examination of the distribution and abundance of less-common species to better understand their ecology. This information is critical to the development of management plans aimed at ecosystem remediation and restoration.

Use of soybean meal and papain to partially replace animal protein for culturing three marine fish species: Fish growth and water quality.

Science.gov (United States)

Mo, W Y; Lau, R S S; Kwok, A C K; Wong, M H

2016-12-01

The main aim of this study was to investigate the feasibility of using soybean meal added with papain to replace half of the fishmeal used in the moist pellets (49% fishmeal and 45% trash fish) developed by the Hong Kong Agriculture, Fisheries and Conservation Department (AFCD) for culturing marine fish. Gold-lined seabream (Rhabdosargus sarba), brown spotted grouper (Epinephelus bleekeri) and pompano (Trachinotus blochii) were farmed at one of the research stations (Kat-O) of AFCD, for a period of 340 days. Results indicated that diets containing papain resulted in better fish growth (reflected by relative weight gain and feed conversion ratio) than diets without papain. In general, wet weight gain of fish depends on the amount of papain added in diet rather than the diet composition. Soybean used in conjunction with papain also contributed to a more effective growth than fish fed with the moist pellets alone. A laboratory experiment (using tanks) was conducted to study the effects of the diets on concentrations of ammonia, nitrite and nitrate in the tank water. Results showed that concentrations of ammonia and nitrate were significantly lower (p marine fish and lower the adverse impact of trash fish and fishmeal on water quality of the mariculture zones. Copyright © 2016 Elsevier Ltd. All rights reserved.

Patterns of presence and concentration of pesticides in fish and waters of the Júcar River (Eastern Spain).

Science.gov (United States)

Belenguer, Vicent; Martinez-Capel, Francisco; Masiá, Ana; Picó, Yolanda

2014-01-30

The Júcar River, in a typical Mediterranean Basin, is expected to suffer a decline in water quality and quantity as a consequence of the climate change. This study is focused on the presence and distribution of pesticides in water and fish, using the first extensive optimization and application of the QuEChERS method to determine pesticides in freshwater fish. Majority pesticides in water - in terms of presence and concentration - were dichlofenthion, chlorfenvinphos, imazalil, pyriproxyfen and prochloraz (associated with a frequent use in farming activities), as well as buprofezin, chlorpyriphos and hexythiazox. In fish, the main compounds were azinphos-ethyl, chlorpyriphos, diazinon, dimethoate and ethion. The analysis of bio-concentration in fish indicated differences by species. The maximum average concentration was detected in European eel (a critically endangered fish species). The wide presence of pesticides in water and fish suggests potential severe effects on fish populations and other biota in future scenarios of climate change, in a river basin with several endemic and endangered fish species. The potential effects of pesticides in combination with multiple stressors require further research to prioritize the management of specific chemicals and suggest effective restoration actions at the basin scale. Copyright © 2013 Elsevier B.V. All rights reserved.

Stream habitat or water quality - what influences stronger fish and macrozoobenthos biodiversity?

Czech Academy of Sciences Publication Activity Database

Adámek, Z.; Jurajda, Pavel

2001-01-01

Roč. 1, č. 3 (2001), s. 305-311 ISSN 1642-3593. [Ecohydrology as a tool for restoration of physically degraded fish habitats. Warsaw, 11.06.2001-13.06.2001] Institutional research plan: CEZ:AV0Z6093917 Keywords : stream ecology * water quality * fish communities Subject RIV: EH - Ecology, Behaviour

The behavioural basis of fish exclusion from coastal power station cooling water intakes

International Nuclear Information System (INIS)

Turnpenny, A.W.H.

1988-08-01

The first principles of fish behaviour in flow fields, and why fish enter water intakes are considered, together with how they can best be excluded. Possible solutions are discussed where fish exclusion is a priority but the ability of fish to detect intakes is likely to be poor due to high turbidity. These involve the use of sound, light or hydraulic stimuli. However, results are likely to be site-specific and field trials would be required. The fish-attractant properties of offshore intake structures are considered. Designers of many existing intake structures have unwittingly incorporated features which are now recognized as fish attractants, in particular, open steelwork superstructures and boulder rip-rap. Such features can be expected to add to the problem of fish ingress. (author)

The Accumulation and Retention of Zine-65 and Cobalt-60 by The Fresh Water Fish CLARIAS LAZERA

International Nuclear Information System (INIS)

Abdel Malik, W.E.Y.; Ibrahim, A.S.; Badawy, S.A.

2003-01-01

Some parameters affecting the accumulation and retention of 65 Zn and 60 Co radionuclides by the fresh water fish CLARIAS LAZERA from the contaminated filtered Ismail ia Canal water(FICW) have been investigated. It has been observed that the accumulated activity (KBq/g) increased with increasing exposure time with the contaminated FICW. This kind of bony fish has been shown to accumulate 65 Zn > 60 Co. The increase of the studied radionuclide carrier concentration in the canal water increased the fish uptake of both radionuclides. The increase of ph of the FICW decreased the accumulated activity by the fish. On the other hand, the retention of those radionuclides by this fish was investigated. It was possible from this study to give preliminary data for the calculation of the radiation dose that might be delivered to man eating the contaminated fish

The accumulation and distribution of 60Co in carp (Cyprinus carpio) in water-fish compartment system

International Nuclear Information System (INIS)

Poppy Intan Tjahaja; Putu Sukmabuana; Eko Susanto

2012-01-01

In relation with nuclear safety assessment, the parameter of radionuclide transfer in the environment is significantly needed for internal doses estimation received by public trough environment - food product - human pathways. International Atomic Energy Agency (IAEA) has published the transfer parameter data for temperate zone in Technical Report Series 472. In order to complete the IAEA data, especially for tropical region, the accumulation and distribution of 60 Co in carp (Cyprinus carpio) was experimentally studied based on the water-fish compartment system. The carp were cultured in 500L water containing 60 Co of about 30 Bq.mL -1 in a water tank. The 60 Co concentration in fish and water were measured using gamma spectrometer. The 60 Co was accumulated and distributed in the fish tissues with the concentration ratio (CR) of 3.08 mL.g -1 1.55 mL.g -1 and 1.14 mL.g -1 for internal organs, bones, and muscle, respectively. The CR of 60 Co in the fish will be useful in internal radiation dose estimation to human trough water-fish-human pathway, and will also complete the IAEA transfer parameter data for tropical region. (author)

Heavy metal contamination of water and fish in peri-urban dams ...

African Journals Online (AJOL)

Heavy metals were measured in water, sediment and fish in dams located downstream of effluent discharge zones in Bulawayo and were compared to those in a pristine upstream dam. Water conductivity indicated pollution of downstream dams. Levels of lead (0.13 – 0.28 ppm) and cadmium (0.02 – 0.06 ppm) in water from ...

Thermal Water of Utah Topical Report

Energy Technology Data Exchange (ETDEWEB)

Goode, Harry D.

1978-11-01

Western and central Utah has 16 areas whose wells or springs yield hot water (35 C or higher), warm water (20-34.5 C), and slightly warm water (15.5-19.5 C). These areas and the highest recorded water temperature for each are: Lower Bear River Area, 105 C; Bonneville Salt Flats, 88 C; Cove Fort-Sulphurdale, 77 C; Curlew Valley, 43 C; East Shore Area, 60 C; Escalante Desert, 149 C; Escalante Valley (Roosevelt, 269 C, and Thermo, 85C); Fish Springs, 60.5 C; Grouse Creek Valley, 42 C; Heber Valley (Midway, 45 C); Jordan Valley, 58.5 C; Pavant Valley-Black Rock Desert, 67 C; Sevier Desert ( Abraham-Crater Hot Springs, 82 C); Sevier Valley (Monroe-Red Hill, 76.5 C, and Joseph Hot Spring, 64 C); Utah Valley, 46 C; and Central Virgin River Basin, 42 C. The only hot water in eastern Utah comes from the oil wells of the Ashley Valley Oil Field, which in 1977 yielded 4400 acre-feet of water at 43 C to 55 C. Many other areas yield warm water (20 to 34.5 C) and slightly warm water (15.5 to 19.5 C). With the possible exception of the Roosevelt KGRA, Crater Hot Springs in the Sevier Desert, Escalante Desert, Pavant-Black Rock, Cove Fort-Sulphurdale, and Coyote Spring in Curlew Valley, which may derive their heat from buried igneous bodies, the heat that warms the thermal water is derived from the geothermal gradient. Meteoric water circulates through fractures or permeable rocks deep within the earth, where it is warmed; it then rises by convection or artesian pressure and issues at the surface as springs or is tapped by wells. Most thermal springs thus rise along faults, but some thermal water is trapped in confined aquifers so that it spreads laterally as it mixes with and warms cooler near-surface water. This spreading of thermal waters is evident in Cache Valley, in Jordan Valley, and in southern Utah Valley; likely the spreading occurs in many other artesian basins where it has not yet been recognized. In the East Shore Area thermal water trapped in confined aquifers warms

Oligocene sea water temperatures offshore Wilkes Land (Antarctica) indicate warm and stable glacial-interglacial variation and show no 'late Oligocene warming'

Science.gov (United States)

Hartman, Julian; Bijl, Peter; Peterse, Francien; Schouten, Stefan; Salabarnada, Ariadna; Bohaty, Steven; Escutia, Carlota; Brinkhuis, Henk; Sangiorgi, Francesca

2017-04-01

At present, warming of the waters below the Antarctic ice shelves is a major contributor to the instability of the Antarctic cryosphere. In order to get insight into future melt behavior of the Antarctic ice sheet, it is important to look at past warm periods that can serve as an analogue for the future. The Oligocene ( 34-23 Ma) is a period within the range of CO2 concentrations predicted by the latest IPCC report for the coming century and is characterized by a very dynamic Antarctic ice sheet, as suggested by benthic δ18O records from ice-distal sites. We suspect that, like today, environmental changes in the Southern Ocean are in part responsible for this dynamicity. To gain more insight into this, we have reconstructed sea water temperatures (SWT) based on Thaumarchaeotal lipids (TEX86) for the Oligocene record obtained from the ice-proximal Site U1356 (Integrated Ocean Drilling Program), offshore Wilkes Land. Part of our record shows a strong coupling between the lithology and SWT, which we attribute to glacial-interglacial variation. Our data shows that both glacial and interglacial temperatures are relatively warm throughout the Oligocene: 14°C and 18°C respectively, which is consistent with previously published estimates based on UK'37 and clumped isotopes for the early Oligocene. Our SST records show only a minor decline between 30 and 24 Ma, and thus show no evidence for a 'late Oligocene warming' as was suggested based on benthic δ18O records from low latitudes. Instead, the discrepancy between our SST trend and the δ18O trend suggests that the late-Oligocene benthic δ18O decrease is likely related to a decline in ice volume. After 24 Ma, however, glacial-interglacial temperature variation appears to increase. In particular, some large temperature drops occur, one of which can be related to the Mi-1 event and a major expansion of the Antarctic ice sheet.

SYMPOSIUM IN ITALY: FISH PHYSIOLOGY, TOXICOLOGY, AND WATER QUALITY

Science.gov (United States)

Scientists from Europe, North America and South America convened in Capri, Italy, April 24-28, 2006 for the Ninth International Symposium on Fish Physiology, Toxicology, and Water Quality. The subject of the meeting was Eutrophication: The toxic effects of ammonia, nitrite and th...

Growth decline linked to warming-induced water limitation in hemi-boreal forests.

Science.gov (United States)

Wu, Xiuchen; Liu, Hongyan; Guo, Dali; Anenkhonov, Oleg A; Badmaeva, Natalya K; Sandanov, Denis V

2012-01-01

Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii), sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year) over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

Testing Wallace's intuition: water type, reproductive isolation and divergence in an Amazonian fish.

Science.gov (United States)

Pires, Tiago H S; Borghezan, Elio A; Machado, Valeria N; Powell, Daniel L; Röpke, Cristhiana P; Oliveira, Claudio; Zuanon, Jansen; Farias, Izeni P

2018-06-01

Alfred Russel Wallace proposed classifying Amazon rivers based on their colour and clarity: white, black and clear water. Wallace also proposed that black waters could mediate diversification and yield distinct fish species. Here, we bring evidence of speciation mediated by water type in the sailfin tetra (Crenuchus spilurus), a fish whose range encompasses rivers of very distinct hydrochemical conditions. Distribution of the two main lineages concords with Wallace's water types: one restricted to the acidic and nutrient-poor waters of the Negro River (herein Rio Negro lineage) and a second widespread throughout the remaining of the species' distribution (herein Amazonas lineage). These lineages occur over a very broad geographical range, suggesting that despite occurring in regions separated by thousands of kilometres, individuals of the distinct lineages fail to occupy each other's habitats, hundreds of metres apart and not separated by physical barrier. Reproductive isolation was assessed in isolated pairs exposed to black-water conditions. All pairs with at least one individual of the lineage not native to black waters showed significantly lower spawning success, suggesting that the water type affected the fitness and contributed to reproductive isolation. Our results endorse Wallace's intuition and highlight the importance of ecological factors in shaping diversity of the Amazon fish fauna. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

Microbiological spoilage of fish and fish products.

Science.gov (United States)

Gram, L; Huss, H H

1996-11-01

Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative biochemical indicators of spoilage. Shewanella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram-positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish is well understood, much less is known about spoilage of lightly preserved fish products. It is concluded that the spoilage is probably caused by lactic acid bacteria, certain psychotrophic Enterobacteriaceae and/or Photobacterium phosphoreum. However, more work is needed in this area.

BACTERIOLOGICAL PROPERTIES OF MARINE WATER IN ADRIATIC FISH FARMS: ENUMERATION OF HETEROTROPHIC BACTERIA

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Emin Teskeredžić

2012-12-01

Full Text Available Aquaculture is currently one of the fastest growing food production sectors in the world. Increase in nutrients and organic wastes lead to general deterioration of water quality. The problem of water quality is associated with both physical and chemical factors, as well as microbiological water quality. Heterotrophic bacteria play an important role in the process of decomposition of organic matter in water environment and indicate eutrophication process. Here we present our experience and knowledge on bacterial properties of marine water in the Adriatic fish farms with European sea bass (Dicentrarchus labrax L., 1758, with an emphasis on enumeration of heterotrophic bacteria in marine water. We applied two temperatures of incubation, as well as two methods for enumeration of heterotrophic bacteria: substrate SimPlate® test and spread plate method on conventional artificial media (Marine agar and Tryptic Soy agar with added NaCl. The results of analysis of bacteriological properties of marine water in the Adriatic fish farms showed that enumeration of heterotrophic bacteria in marine water depends on the applied incubation temperature and media for enumeration. At the same time, the incubation temperature of 22C favours more intense growth of marine heterotrophic bacteria, whereas a SimPlate test gives higher values of heterotrophic bacteria. Volatile values of heterotrophic bacteria during this research indicate a possible deterioration of microbiological water quality in the Adriatic fish farms and a need for regular monitoring of marine water quality.

A Dataset of Deep-Sea Fishes Surveyed by Research Vessels in the Waters around Taiwan

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Kwang-Tsao Shao

2014-12-01

Full Text Available The study of deep-sea fish fauna is hampered by a lack of data due to the difficulty and high cost incurred in its surveys and collections. Taiwan is situated along the edge of the Eurasia fig, at the junction of three Large Marine Ecosystems or Ecoregions of the East China Sea, South China Sea and the Philippines. As nearly two-thirds of its surrounding marine ecosystems are deep-sea environments, Taiwan is expected to hold a rich diversity of deep-sea fish. However, in the past, no research vessels were employed to collect fish data on site. Only specimens, caught by bottom trawl fishing in the waters hundreds of meters deep and missing precise locality information, were collected from Dasi and Donggang fishing harbors. Began in 2001, with the support of National Science Council, research vessels were made available to take on the task of systematically collecting deep-sea fish specimens and occurrence records in the waters surrounding Taiwan. By the end of 2006, a total of 3,653 specimens, belonging to 26 orders, 88 families, 198 genera and 366 species, were collected in addition to data such as sampling site geographical coordinates and water depth, and fish body length and weight. The information, all accessible from the “Database of Taiwan’s Deep-Sea Fauna and Its Distribution (http://deepsea.biodiv.tw/” as part of the “Fish Database of Taiwan,” can benefit the study of temporal and spatial changes in distribution and abundance of fish fauna in the context of global deep-sea biodiversity.

Japanese aquaculture: use of thermal water from power plant

International Nuclear Information System (INIS)

Kuroda, Takeya

1983-01-01

There is some merit of thermal water from power plants in the effect to marine life. Since 1963, the research and development on the aquaculture using this warm water have been carried out at some twenty power plants, seven nuclear and thirteen thermal, some of which are now in the commercial stage. These fish farming projects are operated variously from seed to adult fish production. They can also be classified as land and sea facilities, conforming to the characteristics of the respective sea areas. The current situation in this field and the future prospect are described: thermal aquaculture including seed production and adult fish farming; the projects in nuclear and thermal power plants, respectively; future problems in the facilities, breeding environment and marine life for cultivation. (Mori, K.)

Water clarity of the Colorado River—Implications for food webs and fish communities

Science.gov (United States)

Voichick, Nicholas; Kennedy, Theodore A.; Topping, David; Griffiths, Ronald; Fry, Kyrie

2016-11-01

The closure of Glen Canyon Dam in 1963 resulted in drastic changes to water clarity, temperature, and flow of the Colorado River in Glen, Marble, and Grand Canyons. The Colorado River is now much clearer, water temperature is less variable throughout the year, and the river is much colder in the summer months. The flow—regulated by the dam—is now less variable annually, but has larger daily fluctuations than during pre-dam times. All of these changes have resulted in a different fish community and different food resources for fish than existed before the dam was built. Recent monitoring of water clarity, by measuring turbidity, has helped scientists and river managers understand modern water-clarity patterns in the dam-regulated Colorado River. These data were then used to estimate pre-dam turbidity in the Colorado River in order to make comparisons of pre-dam and dam-regulated conditions, which are useful for assessing biological changes in the river over time. Prior to dam construction, the large sediment load resulted in low water clarity almost all of the time, a condition which was more favorable for the native fish community.

Zn, Pb, Cr and Cd concentrations in fish, water and sediment from ...

African Journals Online (AJOL)

ADOWIE PERE

Zn, Pb, Cr and Cd concentrations in fish, water and sediment from the Azuabie Creek,. Port Harcourt. ... Heavy metal contamination in the aquatic ... Azuabie Creek and the associated water ..... Public in Tianjin, China via Consumption of.

Metal balance shift induced in small fresh water fish by several environmental stresses

International Nuclear Information System (INIS)

Yukawa, Masae; Iso, Hiroyuki; Kodama, Kumiko; Imaseki, Hitoshi; Aoki, Kazuko; Ishikawa, Yuji

2005-01-01

Balance of essential elements in organisms might be changed by environmental stresses. Small fresh water fish, Medaka, was burdened with X-ray irradiation (total dose: 17 Gy), keeping in salty water (70% NaCl of sea water) and keeping in metal containing water (10 ppm of Cr and Co). These stresses are not lethal doses. Essential elements in liver, gall bladder, kidney, spleen, heart and brain in the stress-loaded fish were measured by PIXE method and compared with a control fish to determine the effect of the stresses. Various changes of the elemental contents were observed. Effect of X-ray irradiation was the smallest among the stresses. Relatively high content elements such as P, S, Cl and K were hardly affected with the stresses examined in this work. The effect of Cr on the metal balance seems to be larger than the other stresses. As PIXE method can analyze many elements in a small sample simultaneously, change of elemental distribution in small organisms induced by environmental stresses can be determined readily. (author)

Fish farm and water quality management - doi: 10.4025/actascibiolsci.v35i1.10086

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Lúcia Helena Sipaúba Tavares

2012-12-01

Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 Fish farms’ water quality management is analyzed with regard to the management employed and the different trophic states are compared within the system during the dry and rainy seasons. Six sites were marked two in the water supply (P1 and P2, and four within the fish farm (P3 to P6 . Whereas sites P1 and P2 (water supply were characterized as oligotrophic, the others were mesotrophic and eutrotrophic sites. Environmental variables, mainly nutrients, conductivity, COD, BOD5 and TSS tended to increase as from P3 due to management and fertilization. Greater impact has been registered in the fish farm under analysis for variables COD, ammonia, total phosphorus and TSS during the discharge and pond emptying period. Frequent monitoring of water quality should be undertaken in fish breeding and plankton production ponds, especially in those close to P3 and P4. Removal of sediment in decantation lake or P5 is also recommended to decrease nutrient concentrations, especially phosphorus, accumulated on the bottom soil.

Evaluation of water quality conditions near proposed fish production sites associated with the Yakima Fisheries Project. Final report

International Nuclear Information System (INIS)

Dauble, D.d.; Mueller, R.P.; Martinson, G.A.

1994-05-01

In 1991, the Pacific Northwest Laboratory (PNL) began studying water quality at several sites in the Yakima River Basin for the Bonneville Power Administration. These sites were being proposed as locations for fish culture facilities as part of the Yakima Fisheries Project (YFP). Surface water quality parameters near the proposed fish culture facilities are currently suitable for fish production. Water quality conditions in the mainstream Yakima River and its tributaries are generally excellent in the upper part of the watershed (i.e., near Cle Elum), but they are only fair to poor for the river downstream of Union Gap (river mile 107). Water quality of the Naches River near Oak Flats is also suitable for fish production. Groundwater supplies near the proposed fish production facilities typically have elevated concentrations of metals and dissolved gases. These conditions can be mitigated using best engineering practices such as precipitation and degasification. Additionally, mixing with surface water may improve these conditions. Depending on the location and depth of the well, groundwater temperatures may be warmer than optimum for acclimating and holding juvenile and adult fish. Water quality parameters measured in the Yakima River and tributaries sometimes exceed the range of values described as acceptable for culture of salmonids and for the protection of other aquatic life. However, constituent concentrations are within ranges that exist in many northwest fish hatcheries. Additionally, site-specific tests conducted by PNL (i.e., live box exposures and egg incubation studies) indicate that fish can be successfully reared in surface and well water near the proposed facility sites. Thus, there appear to be no constraints to artificial production for the YFP

The Response of a Branch of Puget Sound, Washington to the 2014 North Pacific Warm Anomaly

Science.gov (United States)

Mickett, J.; Newton, J.; Devol, A.; Krembs, C.; Ruef, W.

2016-02-01

The flow of the unprecedentedly-warm upper-ocean North Pacific "Blob" water into Puget Sound, Washington, caused local extreme water property anomalies that extended from the arrival of the water inshore in the fall of 2014 through 2015. Here we report on moored and seaplane observations from Hood Canal, a branch of Puget Sound, where temperature was more than 2σ above climatology for much of the year with maximum temperature anomalies at depth and at the surface +2.5 °C and +7 °C respectively. The low density of the oceanic warm "Blob" water resulted in weak deep water flushing in Hood Canal in the fall of 2014, which combined with a lack of wintertime flushing to result in anomalously-low dissolved oxygen (DO) concentrations at depth. Late-summer 2015 DO values were the lowest in a decade of mooring observations and more than 2σ below climatology. The anomalously low density of the deep basin water allowed a very early onset of the annually-occurring, late-summer intrusion, which first entered Hood Canal at the end of July compared to the usual arrival in early to mid-September. In late August this intrusion conspired with an early fall storm to lift the very low DO deep water to surface at the south end of Hood Canal, causing a significant fish kill event.

Water flow and fin shape polymorphism in coral reef fishes.

Science.gov (United States)

Binning, Sandra A; Roche, Dominique G

2015-03-01

Water flow gradients have been linked to phenotypic differences and swimming performance across a variety of fish assemblages. However, the extent to which water motion shapes patterns of phenotypic divergence within species remains unknown. We tested the generality of the functional relationship between swimming morphology and water flow by exploring the extent of fin and body shape polymorphism in 12 widespread species from three families (Acanthuridae, Labridae, Pomacentridae) of pectoral-fin swimming (labriform) fishes living across localized wave exposure gradients. The pectoral fin shape of Labridae and Acanthuridae species was strongly related to wave exposure: individuals with more tapered, higher aspect ratio (AR) fins were found on windward reef crests, whereas individuals with rounder, lower AR fins were found on leeward, sheltered reefs. Three of seven Pomacentridae species showed similar trends, and pectoral fin shape was also strongly related to wave exposure in pomacentrids when fin aspect ratios of three species were compared across flow habitats at very small spatial scales (fish body fineless ratio across habitats or depths. Contrary to our predictions, there was no pattern relating species' abundances to polymorphism across habitats (i.e., abundance was not higher at sites where morphology is better adapted to the environment). This suggests that there are behavioral and/or physiological mechanisms enabling some species to persist across flow habitats in the absence of morphological differences. We suggest that functional relationships between swimming morphology and water flow not only structure species assemblages, but are yet another important variable contributing to phenotypic differences within species. The close links between fin shape polymorphism and local water flow conditions appear to be important for understanding species' distributions as well as patterns of diversification across environmental gradients.

The bioconcentration of 131I in fresh water fish

International Nuclear Information System (INIS)

Yu, K.N.; Cheung, T.; Young, E.C.M.; Luo, D.L.

1996-01-01

The dynamic characteristics of the radionuclide concentration process in fresh water fish have been studied. The experimental data for the tilapias were fitted using a simple compartment model to get characteristics parameters such as concentration factors, elimination rate constants, and initial concentration rates, which are 3.08 Bq kg -1 /Bq L -1 , 0.00573 h -1 , and 12.42 Bq kg -1 h -1 , respectively. The relative concentrations of 131 I in different parts, i.e., head, gills, flesh, bone and internal organs, of the tilapias are also determined, which are found to be 10.8, 15.4, 26.1, 11.0, and 37.0%, respectively. The effects of different factors on the transfer of radionuclides in fresh water fishes are also discussed. Experiments on the tilapias and the common carp show that the variation of concentration factors for different species may be significant even for the same radionuclide and the same ecological system. On the other hand, the variation in the concentration factors for the flesh of the tilapias is not significant for a certain range of 131 I concentrations in the water. 12 refs., 1 fig., 1 tab

A preliminary study of the tropical water cycle and its sensitivity to surface warming

Science.gov (United States)

Lau, K. M.; Sui, C. H.; Tao, W. K.

1993-01-01

The Goddard Cumulus Ensemble Model (GCEM) has been used to demonstrate that cumulus-scale dynamics and microphysics play a major role in determining the vertical distribution of water vapor and clouds in the tropical atmosphere. The GCEM is described and is the basic structure of cumulus convection. The long-term equilibrium response to tropical convection to surface warming is examined. A picture of the water cycle within tropical cumulus clusters is developed.

Effective ecological half-lives of Cs-137 for fishes controlled by their surrounding sea-waters

International Nuclear Information System (INIS)

Morita, T.; Yoshida, K.

2004-01-01

National Research Institute of Fisheries Science (NRIFS) has carried out the long term monitoring program for radioactive pollution in marine organisms caught around Japan in order to confirm the safety of marine organisms as food source. Main radionuclide in our monitoring program is Cs-137 because it has the relatively high radiotoxicity and the long term physical half-life (about 30.1 y), and tends to accumulate in the muscle. Recently, the effective ecological half-lives have been introduced to estimate the recovery time from radioactive pollution, and been applicable to various ecosystems. In this study, effective ecological half-lives of Cs-137 for some fishes were calculated from our long term monitoring data. It is known that fish species have each effective ecological half-lives. However, it has been unclear what change the effective ecological half-lives of Cs-137 for fishes. Fishes intake Cs-137 through food chain and directly from their surrounding sea-waters. Accordingly, the effective ecological half-lives of Cs-137 for some fishes would be controlled by the effective environment half-lives of Cs-137 for their surrounding sea-waters. There is difference in effective environment half-lives of Cs-137 between the open ocean and the coastal sea-waters because they have the different input sources of Cs-137. Some fishes move between the open ocean and the coastal areas, and therefore their effective ecological half-lives of Cs-137 are influenced by the effective environment half-lives of Cs-137 for sea-waters of both areas. Consequently, the differences in effective ecological half-lives of Cs-137 among fish species would depend the rate of coastal area in their lives. (author)

UV and hydrogen peroxide treatment restores changes in innate immunity caused by exposure of fish to reuse water.

Science.gov (United States)

Singh, Arvinder; Havixbeck, Jeffrey J; Smith, Matthew K; Shu, Zengquan; Tierney, Keith B; Barreda, Daniel R; El-Din, Mohamed Gamal; Belosevic, Miodrag

2015-03-15

The purpose of this study was to assess the innate immunity of goldfish exposed to reuse water, and UV/H2O2-treated reuse water, using a real-time flow-through exposure system. The reuse water generated by ultrafiltration of finished wastewater from the municipal wastewater treatment plant was analyzed for the presence of a panel of 20 herbicides/fungicides and 46 pharmaceuticals and personal care products (PPCP). There was a seasonal variation in the profile and concentrations of xenobiotics in reuse water with lowest levels occurring in the summer. The innate immunity parameters assessed were cytokine (IFNγ, IL-1β, IL-10, TNFα2), and cytokine receptor (TNFR1, TNFR2, IFNGR1, IFNGR2) gene expression, and phagocytosis of kidney leukocyte subpopulations. Assessment of innate immunity parameters was done after acute (7 days) and sub chronic (30 and 60 days) exposure to reuse water, UV/H2O2-treated reuse water, and activated carbon-treated reuse water (ACT; control), during spring, summer and fall of 2012. Temporal (acute versus sub chronic) as well as seasonal differences in innate immunity of fish exposed to reuse water were observed. The acute exposure of fish to reuse water caused significant down-regulation in cytokine gene expression in different organs of fish (kidney, spleen, liver) and phagocytic ability of different kidney leukocyte subpopulations. The immune gene expression and phagocytosis of kidney leukocytes of fish returned to ACT control levels after sub chronic exposure suggesting that fish have habituated to the reuse water exposure. The changes in gene expression after acute exposure were related to variations in the profile of xenobiotics in reuse water during different seasons. The efficiency of xenobiotic removal using UV/H2O2 ranged between 1.6 and 100% indicating that treatment of reuse water using high dose UV/H2O2 was only partially effective in removing the xenobiotics, as assessed by both chemical analyses and measurement of innate immune

Understanding why the volume of suboxic waters does not increase over centuries of global warming in an Earth System Model

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A. Gnanadesikan

2012-03-01

Full Text Available Global warming is expected to reduce oxygen solubility and vertical exchange in the ocean, changes which would be expected to result in an increase in the volume of hypoxic waters. A simulation made with a full Earth System model with dynamical atmosphere, ocean, sea ice and biogeochemical cycling (the Geophysical Fluid Dynamics Laboratory's Earth System Model 2.1 shows that this holds true if the condition for hypoxia is set relatively high. However, the volume of the most hypoxic (i.e., suboxic waters does not increase under global warming, as these waters actually become more oxygenated. We show that the rise in dissolved oxygen in the tropical Pacific is associated with a drop in ventilation time. A term-by-term analysis within the least oxygenated waters shows an increased supply of dissolved oxygen due to lateral diffusion compensating an increase in remineralization within these highly hypoxic waters. This lateral diffusive flux is the result of an increase of ventilation along the Chilean coast, as a drying of the region under global warming opens up a region of wintertime convection in our model. The results highlight the potential sensitivity of suboxic waters to changes in subtropical ventilation as well as the importance of constraining lateral eddy transport of dissolved oxygen in such waters.

Understanding why the volume of suboxic waters does not increase over centuries of global warming in an Earth System Model

Science.gov (United States)

Gnanadesikan, A.; Dunne, J. P.; John, J.

2012-03-01

Global warming is expected to reduce oxygen solubility and vertical exchange in the ocean, changes which would be expected to result in an increase in the volume of hypoxic waters. A simulation made with a full Earth System model with dynamical atmosphere, ocean, sea ice and biogeochemical cycling (the Geophysical Fluid Dynamics Laboratory's Earth System Model 2.1) shows that this holds true if the condition for hypoxia is set relatively high. However, the volume of the most hypoxic (i.e., suboxic) waters does not increase under global warming, as these waters actually become more oxygenated. We show that the rise in dissolved oxygen in the tropical Pacific is associated with a drop in ventilation time. A term-by-term analysis within the least oxygenated waters shows an increased supply of dissolved oxygen due to lateral diffusion compensating an increase in remineralization within these highly hypoxic waters. This lateral diffusive flux is the result of an increase of ventilation along the Chilean coast, as a drying of the region under global warming opens up a region of wintertime convection in our model. The results highlight the potential sensitivity of suboxic waters to changes in subtropical ventilation as well as the importance of constraining lateral eddy transport of dissolved oxygen in such waters.

A data-mining framework for exploring the multi-relation between fish species and water quality through self-organizing map.

Science.gov (United States)

Tsai, Wen-Ping; Huang, Shih-Pin; Cheng, Su-Ting; Shao, Kwang-Tsao; Chang, Fi-John

2017-02-01

The steep slopes of rivers can easily lead to large variations in river water quality during typhoon seasons in Taiwan, which may poses significant impacts on riverine eco-hydrological environments. This study aims to investigate the relationship between fish communities and water quality by using artificial neural networks (ANNs) for comprehending the upstream eco-hydrological system in northern Taiwan. We collected a total of 276 heterogeneous datasets with 8 water quality parameters and 25 fish species from 10 sampling sites. The self-organizing feature map (SOM) was used to cluster, analyze and visualize the heterogeneous datasets. Furthermore, the structuring index (SI) was adopted to determine the relative importance of each input variable of the SOM and identify the indicator factors. The clustering results showed that the SOM could suitably reflect the spatial characteristics of fishery sampling sites. Besides, the patterns of water quality parameters and fish species could be distinguishably (visually) classified into three eco-water quality groups: 1) typical upstream freshwater fishes that depended the most on dissolved oxygen (DO); 2) typical middle-lower reach riverine freshwater fishes that depended the most on total phosphorus (TP) and ammonia nitrogen; and 3) low lands or pond (reservoirs) freshwater fishes that depended the most on water temperature, suspended solids and chemical oxygen demand. According to the results of the SI, the representative indicators of water quality parameters and fish species consisted of DO, TP and Onychostoma barbatulum. This grouping result suggested that the methodology can be used as a guiding reference to comprehensively relate ecology to water quality. Our methods offer a cost-effective alternative to more traditional methods for identifying key water quality factors relating to fish species. In addition, visualizing the constructed topological maps of the SOM could produce detailed inter-relation between water

Eye-flukes in fish, living in cooling water from nuclear power plants

International Nuclear Information System (INIS)

Hoeglund, J.; Thulin, J.

1988-01-01

We report here on the effects of raised water temperature on the prevalence, mean infrapopulation density and consequences of eye-flukes in fish. The study was mainly performed in the Biotest basin situated 120 km north of Stockholm, Sweden. This 1 km 2 basin is an enclosed brackish water (5 permillage) area receiving heated (about 8 degree C) cooling water (90 m 3 /s) from Forsmark nuclear power station. Both morphological and experimental studies of the parasite larvae of sampled fish indicate that we are dealing with four strains of Diplostomum, two of which occur in perch and the other two in roach. Since taxonomic revisions are under hand elsewhere we prefer to name these strains Diplostomum sp1-4. Metacercariae of D.sp 1 were found between the retina and sclera in the eye of perch while that of D.sp 4 were found in the eye-lens of roach in over 90 % of fish examined. Metacercariae of the other two D.-species and of Tylodelphys clavata and Cotylurus sp were found at lower frequencies. Cercariae of Diplostomum spp were found to develop from sporocysts in snails of the genus Lymnaea. The period of cercarial shedding starts about one month earlier and is also prolonged in the Biotest basin compared to the reference locality. The infection procedure, however, is the same in both areas. During experimental infections with cercariae on yearlings of bleak we found a distinct correlation between an increased fry mortality and an increased cercariae density, a connection which was strengthened at increased water temperature. Furthermore, the results indicate that the defence mechanisms of the fish respond slower towards infections with Diplostomum spp than that is known to be the case with bacterial infections. The speed with which the metacercariae accumulate in the eye of the fish is higher in the Biotest basin than in the reference locality. In spite of this, the mean infrapopulation density of metacercariae in older fish is not higher here than in the reference

Mercury concentrations in China's coastal waters and implications for fish consumption by vulnerable populations

International Nuclear Information System (INIS)

Tong, Yindong; Wang, Mengzhu; Bu, Xiaoge; Guo, Xin; Lin, Yan; Lin, Huiming; Li, Jing; Zhang, Wei; Wang, Xuejun

2017-01-01

We assessed mercury (Hg) pollution in China's coastal waters, including the Bohai Sea, the Yellow Sea, the East China Sea and the South China Sea, based on a nationwide dataset from 301 sampling sites. A methylmercury (MeHg) intake model for humans based on the marine food chain and human fish consumption was established to determine the linkage between water pollutants and the pollutant intake by humans. The predicted MeHg concentration in fish from the Bohai Sea was the highest among the four seas included in the study. The MeHg intake through dietary ingestion was dominant for the fish and was considerably higher than the MeHg intake through water respiration. The predicted MeHg concentrations in human blood in the coastal regions of China ranged from 1.37 to 2.77 μg/L for pregnant woman and from 0.43 to 1.00 μg/L for infants, respectively, based on different diet sources. The carnivorous fish consumption advisory for pregnant women was estimated to be 288–654 g per week to maintain MeHg concentrations in human blood at levels below the threshold level (4.4 μg/L established by the US Environmental Protection Agency). With a 50% increase in Hg concentrations in water in the Bohai Sea, the bioaccumulated MeHg concentration (4.5 μg/L) in the fish consumers will be higher than the threshold level. This study demonstrates the importance in controlling Hg pollution in China's coastal waters. An official recommendation guideline for the fish consumption rate and its sources will be necessary for vulnerable populations in China. - Graphical abstract: MeHg transfer route from the marine food chain to vulnerable population. - Highlights: • Predicted MeHg concentrations in pregnant woman and infant’s blood in China’s coastal regions are below threshold level. • The carnivorous fish consumption advisory for pregnant women is estimated to be 288–654 g per week. g • If with a 50% increase in Hg in Bohai Sea, the bioaccumulated MeHg concentration in

Thermal tolerances of fish from a reservoir receiving heated effluent from a nuclear reactor

International Nuclear Information System (INIS)

Holland, W.E.; Smith, M.H.; Gibbons, J.W.; Brown, D.H.

1974-01-01

The heat tolerances of bluegill (Lepomis macrochirus) subjected to heated effluent from a nuclear reactor was compared with those of bluegill living at normal temperatures. Three of the four study areas were located in the Par Pond reservoir system on the Savannah River Plant near Aiken, South Carolina. Results shown that at least one species of warm-water fish can adjust to elevated aquatic temperatures in a natural environment by becoming more tolerant. (U.S.)

Growth decline linked to warming-induced water limitation in hemi-boreal forests.

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Xiuchen Wu

Full Text Available Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii, sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

Improving Conservation of Florida Manatees ( Trichechus manatus latirostris): Conceptualization and Contributions Toward a Regional Warm-Water Network Management Strategy for Sustainable Winter Habitat

Science.gov (United States)

Flamm, Richard Owen; Reynolds, John Elliot; Harmak, Craig

2013-01-01

We used southwestern Florida as a case study to lay the groundwork for an intended and organized decision-making process for managing warm-water habitat needed by endangered manatees to survive winters in Florida. Scientists and managers have prioritized (a) projecting how the network of warm-water sites will change over the next 50 years as warmed industrial discharges may expire and as flows of natural springs are reduced through redirection of water for human uses, and (b) mitigating such changes to prevent undue consequences to manatees. Given the complexities introduced by manatee ecology; agency organizational structure; shifting public demands; fluctuating resource availability; and managing within interacting cultural, social, political, and environmental contexts, it was clear that a structured decision process was needed. To help promote such a process, we collected information relevant to future decisions including maps of known and suspected warm-water sites and prototyped a characterization of sites and networks. We propose steps that would lead to models that might serve as core tools in manatee/warm-water decision-making, and we summarized topics relevant for informed decision-making (e.g., manatee spatial cognition, risk of cold-stress morbidity and mortality, and human dimensions). A major impetus behind this effort is to ensure proactively that robust modeling tools are available well in advance of the anticipated need for a critical management decision.

The trace element analysis in freshwater fish species, water and sediment in Iyidere stream (Rize-Turkey).

Science.gov (United States)

Verep, Bulent; Mutlu, Cengiz; Apaydin, Gokhan; Cevik, Ugur

2012-07-15

Many environmental problems like dam construction, agricultural debris, flooding and industrial establishments threaten Iyidere stream (Rize, Turkey) on the southeastern coast of the Black Sea (Turkey). The trace element concentrations in water, fish and sediments in lyidere stream (Rize, Turkey) were investigated in this study. The concentration of six different elements in ten freshwater fish species and sediment was determined using energy dispersive X-ray fluorescence method. A radioisotope excited X-ray fluorescence analysis using the method of multiple standard addition is applied for the elemental analysis of fish and sediments. Water samples for trace metals were analyzed using standard spectrophotometry methods. A qualitative analysis of spectral peaks showed that ten different freshwater fish samples (Chondrostoma colchicum, Chalcalburnus chalcoides, Salmo trutta labrax, Alburnoides bipunctatus, Leuciscus cephalus, Barbus taurus escherichia, Capoeta tinca, Neogobius kessleri, Rutilus frisii, Lampetra lanceolata) and sediment contained phosphorus (P), sulphur (S), chlorine (Cl), potassium (K), calcium (Ca) and titanium (Ti). Heavy metals as toxic elements for biota (Pb, Cd, Hg, Zn and Mn etc.) were not detected in fish, water and sediments. Thus, It can be declared that freshwater fish of Iyidere does not contains health risks for consumers in terms of metal pollution.

Low flows and water temperature risks to Asian coal power plants in a warming world

Science.gov (United States)

Wang, Y.; Byers, E.; Parkinson, S.; Wanders, N.; Wada, Y.; Bielicki, J. M.

2017-12-01

Thermoelectric power generation requires cooling, normally provided by wet cooling systems. The withdrawal and discharge of cooling water are subject to regulation. Therefore, operation of power plants may be vulnerable to changes in streamflow and rises in water temperatures. In Asia, about 489 GW of coal-fired power plants are currently under construction, permitted, or announced. Using a comprehensive dataset of these planned coal power plants (PCPPs) and cooling water use models, we investigated whether electricity generation at these power plants will be limited by streamflow and water temperature. Daily streamflow and water temperature time series are from the high-resolution (0.08ox0.08o) runs of the PCRGLOBWB hydrological model, driven by downscaled meteorological forcing from five global climate models. We compared three climate change scenarios (1.5oC, 2oC, and 3oC warming in global mean temperature) and three cooling system choice scenarios (freshwater once-through, freshwater cooling tower, and "business-as-usual" - where a PCPP uses the same cooling system as the nearest existing coal power plant). The potential available capacity of the PCPPs increase slightly from the 1.5oC to the 2oC and 3oC warming scenario due to increase in streamflow. The once-through cooling scenario results in virtually zero available capacity at the PCPPs. The other two cooling scenarios result in about 20% of the planned capacity being unavailable under all warming scenarios. Hotspots of the most water-limited PCPPs are in Pakistan, northwestern India, northwestern and north-central China, and northern Vietnam, where most of the PCPPs will face 30% to 90% unavailable nameplate capacity on annual average. Since coal power plants cannot operate effectively when the capacity factor falls below a minimum load level (about 20% to 50%), the actual limitation on generation capacity would be larger. In general, the PCPPs that will have the highest limitation on annual average

Warm Water Oxidation Verification - Scoping and Stirred Reactor Tests

Energy Technology Data Exchange (ETDEWEB)

Braley, Jenifer C.; Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2011-06-15

Scoping tests to evaluate the effects of agitation and pH adjustment on simulant sludge agglomeration and uranium metal oxidation at {approx}95 C were performed under Test Instructions(a,b) and as per sections 5.1 and 5.2 of this Test Plan prepared by AREVA. (c) The thermal testing occurred during the week of October 4-9, 2010. The results are reported here. For this testing, two uranium-containing simulant sludge types were evaluated: (1) a full uranium-containing K West (KW) container sludge simulant consisting of nine predominant sludge components; (2) a 50:50 uranium-mole basis mixture of uraninite [U(IV)] and metaschoepite [U(VI)]. This scoping study was conducted in support of the Sludge Treatment Project (STP) Phase 2 technology evaluation for the treatment and packaging of K-Basin sludge. The STP is managed by CH2M Hill Plateau Remediation Company (CHPRC) for the U.S. Department of Energy. Warm water ({approx}95 C) oxidation of sludge, followed by immobilization, has been proposed by AREVA and is one of the alternative flowsheets being considered to convert uranium metal to UO{sub 2} and eliminate H{sub 2} generation during final sludge disposition. Preliminary assessments of warm water oxidation have been conducted, and several issues have been identified that can best be evaluated through laboratory testing. The scoping evaluation documented here was specifically focused on the issue of the potential formation of high strength sludge agglomerates at the proposed 95 C process operating temperature. Prior hydrothermal tests conducted at 185 C produced significant physiochemical changes to genuine sludge, including the formation of monolithic concretions/agglomerates that exhibited shear strengths in excess of 100 kPa (Delegard et al. 2007).

Warm Water Oxidation Verification - Scoping and Stirred Reactor Tests

International Nuclear Information System (INIS)

Braley, Jenifer C.; Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2011-01-01

Scoping tests to evaluate the effects of agitation and pH adjustment on simulant sludge agglomeration and uranium metal oxidation at ∼95 C were performed under Test Instructions(a,b) and as per sections 5.1 and 5.2 of this Test Plan prepared by AREVA. (c) The thermal testing occurred during the week of October 4-9, 2010. The results are reported here. For this testing, two uranium-containing simulant sludge types were evaluated: (1) a full uranium-containing K West (KW) container sludge simulant consisting of nine predominant sludge components; (2) a 50:50 uranium-mole basis mixture of uraninite (U(IV)) and metaschoepite (U(VI)). This scoping study was conducted in support of the Sludge Treatment Project (STP) Phase 2 technology evaluation for the treatment and packaging of K-Basin sludge. The STP is managed by CH2M Hill Plateau Remediation Company (CHPRC) for the U.S. Department of Energy. Warm water (∼95 C) oxidation of sludge, followed by immobilization, has been proposed by AREVA and is one of the alternative flowsheets being considered to convert uranium metal to UO 2 and eliminate H 2 generation during final sludge disposition. Preliminary assessments of warm water oxidation have been conducted, and several issues have been identified that can best be evaluated through laboratory testing. The scoping evaluation documented here was specifically focused on the issue of the potential formation of high strength sludge agglomerates at the proposed 95 C process operating temperature. Prior hydrothermal tests conducted at 185 C produced significant physiochemical changes to genuine sludge, including the formation of monolithic concretions/agglomerates that exhibited shear strengths in excess of 100 kPa (Delegard et al. 2007).

Oxidative stability of 70% fish oil‐in‐water emulsions: Impact of emulsifiers and pH

DEFF Research Database (Denmark)

Horn, Anna Frisenfeldt; Nielsen, Nina Skall; Andersen, Ulf

2011-01-01

The objective of this study was to evaluate the protective effects of five different emulsifiers on lipid oxidation in 70% fish oil‐in‐water emulsions to be used as delivery systems for long chain polyunsaturated omega‐3 fatty acids to foods. The emulsifiers were either phospholipid (PL) based......‐in‐water emulsions prepared with whey protein isolate, sodium caseinate, milk phospholipids, or soy lecithin. The emulsions can be used as delivery systems for fish oil to foods. However, only emulsions prepared with proteins at high pH offered advantages with respect to better oxidative stability during storage...... compared to neat fish oil. Thus, when fish oil is added to a food product in a delivery emulsion, the type of emulsion used should be carefully considered....

Characterization of water quality and biological communities, Fish Creek, Teton County, Wyoming, 2007-2011

Science.gov (United States)

Eddy-Miller, Cheryl A.; Peterson, David A.; Wheeler, Jerrod D.; Edmiston, C. Scott; Taylor, Michelle L.; Leemon, Daniel J.

2013-01-01

Fish Creek, an approximately 25-kilometer-long tributary to Snake River, is located in Teton County in western Wyoming near the town of Wilson. Fish Creek is an important water body because it is used for irrigation, fishing, and recreation and adds scenic value to the Jackson Hole properties it runs through. Public concern about nuisance growths of aquatic plants in Fish Creek has been increasing since the early 2000s. To address these concerns, the U.S. Geological Survey conducted a study in cooperation with the Teton Conservation District to characterize the hydrology, water quality, and biologic communities of Fish Creek during 2007–11. The hydrology of Fish Creek is strongly affected by groundwater contributions from the area known as the Snake River west bank, which lies east of Fish Creek and west of Snake River. Because of this continuous groundwater discharge to the creek, land-use activities in the west bank area can affect the groundwater quality. Evaluation of nitrate isotopes and dissolved-nitrate concentrations in groundwater during the study indicated that nitrate was entering Fish Creek from groundwater, and that the source of nitrate was commonly a septic/sewage effluent or manure source, or multiple sources, potentially including artificial nitrogen fertilizers, natural soil organic matter, and mixtures of sources. Concentrations of dissolved nitrate and orthophosphate, which are key nutrients for growth of aquatic plants, generally were low in Fish Creek and occasionally were less than reporting levels (not detected). One potential reason for the low nutrient concentrations is that nutrients were being consumed by aquatic plant life that increases during the summer growing season, as a result of the seasonal increase in temperature and larger number of daylight hours. Several aspects of Fish Creek’s hydrology contribute to higher productivity and biovolume of aquatic plants in Fish Creek than typically observed in streams of its size in

Solar water heating for aquaculture : optimizing design for sustainability

Energy Technology Data Exchange (ETDEWEB)

McDonald, M.; Thwaites, J. [Taylor Munro Energy Systems Inc., Delta, BC (Canada)

2003-08-01

This paper presents the results of a solar water heating project at Redfish Ranch, the first Tilapia tropical fish farm in British Columbia. The fish are raised in land-based tanks, eliminating the risk of contamination of local ecosystems. As a tropical species, they requires warm water. Natural gas or propane boilers are typically used to maintain tank temperatures at 26 to 28 degrees C. Redfish Ranch uses solar energy to add heat to the fish tanks, thereby reducing fossil-fuel combustion and greenhouse gas emissions. This unique building-integrated solar system is improving the environmental status of of this progressive industrial operation by offsetting fossil-fuel consumption. The system was relatively low cost, although substantial changes had to be made to the roof of the main building. The building-integrated design of the solar water heating system has reduced operating costs, generated local employment, and shows promise of future activity. As such, it satisfies the main criteria for sustainability. 7 refs.

Artificial climate warming positively affects arbuscular mycorrhizae but decreases soil aggregate water stability in an annual grassland

Energy Technology Data Exchange (ETDEWEB)

Rillig, M.C.; Wright, S.F.; Shaw, M.R.; Field, C.B.

2002-04-01

Despite the importance of arbuscular mycorrhizae to the functioning of terrestrial ecosystems (e.g. nutrient uptake, soil aggregation), and the increasing evidence of global warming, responses of arbuscular mycorrhizal fungi (AMF) to climate warming are poorly understood. In a field experiment using infrared heaters, we found effects of warming on AMF after one growing season in an annual grassland, in the absence of any effects on measured root parameters (weight, length, average diameter). AMF soil hyphal length was increased by over 40% in the warmed plots, accompanied by a strong trend for AMF root colonization increase. In the following year, root weight was again not significantly changed, and AMF root colonization increased significantly in the warmed plots. Concentration of the soil protein glomalin, a glycoprotein produced by AMF hyphae with importance in soil aggregation, was decreased in the warmed plots. Soil aggregate water stability, measured for five diameter size classes, was also decreased significantly. In the following year, soil aggregate weight in two size classes was decreased significantly, but the effect size was very small. These results indicate that ecosystem warming may have stimulated carbon allocation to AMF. Other factors either influenced glomalin decomposition or production, hence influencing the role of these symbionts in soil aggregation. The observed small changes in soil aggregation, if widespread among terrestrial ecosystems, could have important consequences for soil carbon storage and erosion in a warmed climate, especially if there are cumulative effects of warming. (au)

Fish Welfare in Aquaponic Systems: Its Relation to Water Quality with an Emphasis on Feed and Faeces—A Review

Directory of Open Access Journals (Sweden)

Hijran Yavuzcan Yildiz

2017-01-01

Full Text Available Aquaponics is the combination of aquaculture (fish and hydroponic cultivation of plants. This review examines fish welfare in relation to rearing water quality, fish feed and fish waste and faeces to develop a sustainable aquaponic system where the co-cultured organisms, fish, bacteria in biofilters and plants, should be considered holistically in all aquaponics operations. Water quality parameters are the primary environmental consideration for optimizing aquaponic production and for directly impacting fish welfare/health issues and plant needs. In aquaponic systems, the uptake of nutrients should be maximised for the healthy production of the plant biomass but without neglecting the best welfare conditions for the fish in terms of water quality. Measures to reduce the risks of the introduction or spread of diseases or infection and to increase biosecurity in aquaponics are also important. In addition, the possible impacts of allelochemicals, i.e., chemicals released by the plants, should be taken into account. Moreover, the effect of diet digestibility, faeces particle size and settling ratio on water quality should be carefully considered. As available information is very limited, research should be undertaken to better elucidate the relationship between appropriate levels of minerals needed by plants, and fish metabolism, health and welfare. It remains to be investigated whether and to what extent the concentrations of suspended solids that can be found in aquaponic systems can compromise the health of fish. Water quality, which directly affects fish health and well-being, is the key factor to be considered in all aquaponic systems.

Mercury in sediment, water, and fish in a managed tropical wetland-lake ecosystem.

Science.gov (United States)

Malczyk, Evan A; Branfireun, Brian A

2015-08-15

Mercury pollution has not been well documented in the inland lakes or fishes of Mexico, despite the importance of freshwater fish as a source of protein in local diets. Total mercury and methylmercury in waters, sediments, and the commercial fish catch were investigated in Lake Zapotlán, Mexico. Concentrations of total and methylmercury were very high in runoff and wastewater inputs, but very low in sediments and surface waters of the open water area of the lake. Concentrations of total mercury in tilapia and carp were very low, consistent with the low concentrations in lake water and sediments. Particle settling, sorption, the biogeochemical environment, and/or bloom dilution are all plausible explanations for the significant reductions in both total mercury and methylmercury. Despite very high loading of mercury, this shallow tropical lake was not a mercury-impaired ecosystem, and these findings may translate across other shallow, alkaline tropical lakes. Importantly, the ecosystem services that seemed to be provided by peripheral wetlands in reducing mercury inputs highlight the potential for wetland conservation or restoration in Mexico. Copyright © 2015. Published by Elsevier B.V.

Radioactivity of surface water and freshwater fish in Finland in 1987

International Nuclear Information System (INIS)

Saxen, R.

1990-05-01

Changes over time in the activity concentrations of radionuclides in surface water were monitored as in the previous year. Monitoring of the radioactivity transported by the largest rivers to the Baltic Sea was also continued. All samples were analysed gammaspectrometrically and for 90 Sr. Some water samples were analysed for tritium. The dominant gamma-emitting radionuclides were 137 Cs and 134 Cs. The uneven distribution of Chernobyl deposition is still seen in the results. The activity concentrations of 137 Cs have decreased significantly: In the drainage area where the activity concentrations were highest after the Chernobyl accident the concentrations in October 1987 were only about 7% of the values in May 1986. The decrease in the activity concentrations of 90 Sr was much slighter. The study on areal and temporal changes in the activity concentrations of 137 Cs in fish was expanded in 1987. In all about 1550 samples were analysed gammaspectrometrically and a few samples were also analysed radiochemically for 90 Sr. Fifteen different fish species were included in the study. The highest activity concentrations of 137 Cs were detected in small oligotrophic lakes in the area of highest deposition. The level of 137 Cs in non-predatory fish had clearly decreased, while that in predatory fish was almost double what it had been in 1986. The average intake of 137 Cs via freshwater fish countrywide was about 4200 Bq a -1 in 1987. The average intakes in the various drainage basins ranged from about 500 Bq to 6600 Bq in 1987. The mean activity concentrations of 137 Cs in the three fish groups (predatory, non-predatory and intermediate groups) countrywide were 1300, 600 and 1300 Bq kg -1 in 1987, respectively

Franz Josef Land: extreme northern outpost for Arctic fishes

Directory of Open Access Journals (Sweden)

Natalia V. Chernova

2014-12-01

Full Text Available The remote Franz Josef Land (FJL Archipelago is the most northerly land in Eurasia and its fish fauna, particularly in nearshore habitats, has been poorly studied. An interdisciplinary expedition to FJL in summer 2013 used scuba, seines, and plankton nets to comprehensively study the nearshore fish fauna of the archipelago. We present some of the first underwater images for many of these species in their natural habitats. In addition, deep water drop cameras were deployed between 32 and 392 m to document the fish fauna and their associated habitats at deeper depths. Due to its high latitude (79°–82°N, extensive ice cover, and low water temperatures (<0 °C much of the year, the fish diversity at FJL is low compared to other areas of the Barents Sea. Sixteen species of fishes from seven families were documented on the expedition, including two species previously unknown to the region. One Greenland shark, Somniosus microcephalus (Somniosidae, ca. 2 m in length, was recorded by drop camera near Hayes Island at 211 m, and Esipov’s pout, Gymnelus esipovi (Zoarcidae, was collected at Wilton Island at 15 m in a kelp forest. Including the tape-body pout, Gymnelus taeniatus, described earlier from the sub-littoral zone of Kuhn Island, 17 fish species are now known from FJL’s nearshore waters. Species endemic to the Arctic accounted for 75% of the nearshore species observed, followed by species with wider ranges. A total of 43 species from 15 families are known from FJL with the majority of the records from offshore trawl surveys between 110 and 620 m. Resident species have mainly high Arctic distributions, while transient species visit the archipelago to feed (e.g., Greenland shark, and others are brought by currents as larvae and later migrate to spawn grounds in the south (e.g., Atlantic cod Gadus morhua, Capelin Mallotus villosus, Beaked redfish Sebastes mentella. Another species group includes warmer-water fishes that are rare waifs (e

Interbasin water transfer, riverine connectivity, and spatial controls on fish biodiversity

Science.gov (United States)

Grant, Evan H. Campbell; Lynch, Heather J.; Muneepeerakul, Rachata; Muthukumarasamy, Arunachalam; Rodríguez-Iturbe, Ignacio; Fagan, William F.

2012-01-01

Background Large-scale inter-basin water transfer (IBWT) projects are commonly proposed as solutions to water distribution and supply problems. These problems are likely to intensify under future population growth and climate change scenarios. Scarce data on the distribution of freshwater fishes frequently limits the ability to assess the potential implications of an IBWT project on freshwater fish communities. Because connectivity in habitat networks is expected to be critical to species' biogeography, consideration of changes in the relative isolation of riverine networks may provide a strategy for controlling impacts of IBWTs on freshwater fish communities Methods/Principal Findings Using empirical data on the current patterns of freshwater fish biodiversity for rivers of peninsular India, we show here how the spatial changes alone under an archetypal IBWT project will (1) reduce freshwater fish biodiversity system-wide, (2) alter patterns of local species richness, (3) expand distributions of widespread species throughout peninsular rivers, and (4) decrease community richness by increasing inter-basin similarity (a mechanism for the observed decrease in biodiversity). Given the complexity of the IBWT, many paths to partial or full completion of the project are possible. We evaluate two strategies for step-wise implementation of the 11 canals, based on economic or ecological considerations. We find that for each step in the project, the impacts on freshwater fish communities are sensitive to which canal is added to the network. Conclusions/Significance Importantly, ecological impacts can be reduced by associating the sequence in which canals are added to characteristics of the links, except for the case when all 11 canals are implemented simultaneously (at which point the sequence of canal addition is inconsequential). By identifying the fundamental relationship between the geometry of riverine networks and freshwater fish biodiversity, our results will aid in

A synthesis of ecological and fish-community changes in Lake Ontario, 1970-2000

Science.gov (United States)

Mills, E.L.; Casselman, J.M.; Dermott, R.; Fitzsimons, J.D.; Gal, G.; Holeck, K. T.; Hoyle, J.A.; Johannsson, O.E.; Lantry, B.F.; Makarewicz, J.C.; Millard, E.S.; Munawar, I.F.; Munawar, M.; O'Gorman, R.; Owens, R.W.; Rudstam, L. G.; Schaner, T.; Stewart, T.J.

2005-01-01

We assessed stressors associated with ecological and fishcommunity changes in Lake Ontario since 1970, when the first symposium on Salmonid Communities in Oligotrophic Lakes (SCOL I) was held (J. Fish. Res. Board Can. 29: 613-616). Phosphorus controls implemented in the early 1970s were undeniably successful; lower food-web studies showed declines in algal abundance and epilimnetic zooplankton production and a shift in pelagic primary productivity toward smaller organisms. Stressors on the fish community prior to 1970 such as exploitation, sea lamprey (Petromyzon marinus) predation, and effects of nuisance populations of alewife (Alosa pseudoharengus) were largely ameliorated by the 1990s. The alewife became a pivotal species supporting a multi-million-dollar salmonid sport fishery, but alewife-induced thiamine deficiency continued to hamper restoration and sustainability of native lake trout (Salvelinus namaycush). Expanding salmonine populations dependent on alewife raised concerns about predator demand and prey supply, leading to reductions in salmonine stocking in the early 1990s. Relaxation of the predation impact by alewives and their shift to deeper water allowed recovery of native fishes such as threespine stickleback (Gasterosteus aculeatus) and emerald shiner (Notropis atherinoides). The return of the Lake Ontario ecosystem to historical conditions has been impeded by unplanned introductions. Establishment of Dreissena spp. led to increased water clarity and increased vectoring of lower trophic-level production to benthic habitats and contributed to the collapse of Diporeia spp. populations, behavioral modifications of key fish species, and the decline of native lake whitefish (Coregonus clupeaformis). Despite reduced productivity, exotic-species introductions, and changes in the fish community, offshore Mysis relicta populations remained relatively stable. The effects of climate and climate change on the population abundance and dynamics of Lake Ontario

Radioactive contamination of some important fish species in fish ponds and natural waters with special attention to 90Sr radioisotope accumulation Pt. 1

International Nuclear Information System (INIS)

Kantor, D.; Szentjobi, O.

1977-01-01

The radioactive contamination accumulated in the organs and bones of fishes, a major protein source for mankind, depends on the radioactive contamination of waters and aquatic vegetation. In addition to the activity per gram of water, K, Ca, and chloride contents of waters and oxygen consumption were studied, since radioactivity and radioactive material enrichment in natural waters are the consequence of complex geological and physico-chemical processes. The origin of the differences in radioactivity of rivers, lakes and fish ponds is tentatively explained from the results of analytical and radiometric measurements of waters. Results of similar investigations on aquatic and coastal vegetation of these waters cannot be explained in a simple way because the answer is uncertain due to the compositional differences of plant specimens and the sampling in changing seasons. Therefore, additional investigations are proposed. (P.J.)

Observed vulnerability of Filchner-Ronne Ice Shelf to wind-driven inflow of warm deep water

Science.gov (United States)

Darelius, E.; Fer, I.; Nicholls, K. W.

2016-01-01

The average rate of melting at the base of the large Filchner-Ronne Ice Shelf in the southern Weddell Sea is currently low, but projected to increase dramatically within the next century. In a model study, melt rates increase as changing ice conditions cause a redirection of a coastal current, bringing warm water of open ocean origin through the Filchner Depression and into the Filchner Ice Shelf cavity. Here we present observations from near Filchner Ice Shelf and from the Filchner Depression, which show that pulses of warm water already arrive as far south as the ice front. This southward heat transport follows the eastern flank of the Filchner Depression and is found to be directly linked to the strength of a wind-driven coastal current. Our observations emphasize the potential sensitivity of Filchner-Ronne Ice Shelf melt rates to changes in wind forcing. PMID:27481659

Quantifying effects of hydrological and water quality disturbances on fish with food-web modeling

Science.gov (United States)

Zhao, Changsen; Zhang, Yuan; Yang, Shengtian; Xiang, Hua; Sun, Ying; Yang, Zengyuan; Yu, Qiang; Lim, Richard P.

2018-05-01

Accurately delineating the effects of hydrological and water quality habitat factors on the aquatic biota will significantly assist the management of water resources and restoration of river ecosystems. However, current models fail to comprehensively consider the effects of multiple habitat factors on the development of fish species. In this study, a dynamic framework for river ecosystems was set up to explore the effects of multiple habitat factors in terms of hydrology and water quality on the fish community in rivers. To achieve this the biomechanical forms of the relationships between hydrology, water quality, and aquatic organisms were determined. The developing processes of the food web without external disturbance were simulated by 208 models, constructed using Ecopath With Ecosim (EWE). These models were then used to analyze changes in biomass (ΔB) of two representative fish species, Opsariichthys bidens and Carassius auratus, which are widely distributed in Asia, and thus have attracted the attention of scholars and stakeholders, due to the consequence of habitat alteration. Results showed that the relationship between the changes in fish biomass and key habitat factors can be expressed in a unified form. T-tests for the unified form revealed that the means of the two data sets of simulated and observed ΔB for these two fish species (O. bidens and C. auratus) were equal at the significance level of 5%. Compared with other ecological dynamic models, our framework includes theories that are easy to understand and has modest requirements for assembly and scientific expertise. Moreover, this framework can objectively assess the influence of hydrological and water quality variance on aquatic biota with simpler theory and little expertise. Therefore, it is easy to be put into practice and can provide a scientific support for decisions in ecological restoration made by river administrators and stakeholders across the world.

Comparing the Life Cycle Energy Consumption, Global Warming and Eutrophication Potentials of Several Water and Waste Service Options

Science.gov (United States)

Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG...

Concentration of radionuclides in fresh water fish downstream of Rancho Seco Nuclear Generating Plant

International Nuclear Information System (INIS)

Noshkin, V.E.; Eagle, R.J.; Dawson, J.M.; Brunk, J.L.; Wong, X.M.

1984-01-01

Fish were collected for radionuclide analysis over a 5-month period in 1984 from creeks downstream of the Rancho Seco Nuclear Generating Plant, which has been discharging quantities of some fission and activation products to the waterway since 1981. Among the fish, the bluegill was selected for intensive study because it is very territorial and the radionuclide concentrations detected should be representative of the levels in the local environment at the downstream locations sampled. Among the gamma-emitting radionuclides routinely released, only 134 Cs and 137 Cs were detected in the edible flesh of fish. Concentrations in the flesh of fish decreased with distance from the plant. The relationship between concentration and distance was determined to be exponential. Exponential equations were generated to estimate concentrations in fish at downstream locations where no site-specific information was available. Mean concentrations of 137 Cs in bluegill collected during April, May, July and August from specific downstream stations were not significantly different in spite of the release of 131 mCi to the creeks between April and August. The concentrations in fish are not responding to changes in water concentrations brought about by plant discharges. Diet appears to be a more significant factor than size or weight or water concentration in regulating body burdens of 137 Cs in these fish

Is the distribution of Prochlorococcus and Synechococcus ecotypes in the Mediterranean Sea affected by global warming?

Science.gov (United States)

Mella-Flores, D.; Mazard, S.; Humily, F.; Partensky, F.; Mahé, F.; Bariat, L.; Courties, C.; Marie, D.; Ras, J.; Mauriac, R.; Jeanthon, C.; Mahdi Bendif, E.; Ostrowski, M.; Scanlan, D. J.; Garczarek, L.

2011-09-01

Biological communities populating the Mediterranean Sea, which is situated at the northern boundary of the subtropics, are often claimed to be particularly affected by global warming. This is indicated, for instance, by the introduction of (sub)tropical species of fish or invertebrates that can displace local species. This raises the question of whether microbial communities are similarly affected, especially in the Levantine basin where sea surface temperatures have significantly risen over the last 25 years (0.50 ± 0.11 °C in average per decade, P Lions and by clade III and groups genetically related to clades WPC1 and VI in the rest of the Mediterranean Sea. In contrast, only a few sequences of clade II, a group typical of warm waters, were observed. These data indicate that local cyanobacterial populations have not yet been displaced by their (sub)tropical counterparts.

A Spatio-Temporal Model of Phenotypic Evolution in the Atlantic Silverside (Menidia menidia) and Its Implications for Size-Selective Fishing in a Warmer World

Science.gov (United States)

Sbrocco, E. J.

2016-02-01

A pervasive phenotypic pattern observed across marine fishes is that vertebral number increases with latitude. Jordan's Rule, as it is known, holds true both within and across species, and like other ecogeographic principles (e.g., Bergmann's Rule), it is presumed to be an adaptive response to latitudinal gradients in temperature. As such, future ocean warming is expected to impact not only the geographic range limits of marine fishes that conform to Jordan's Rule, but also their phenotype, with warmer waters selecting for fish with fewer vertebrae at any given latitude. Here I present a model of phenotypic evolution over space and time for the Atlantic silverside (Menidia menidia), a common marine fish found in coastal waters along the western North Atlantic. This species has long served as a model organism for the study of fisheries-induced selection and exhibits numerous latitudinal clines in phenotypic and life-history traits, including vertebral number. Common garden experiments have shown that vertebral number is genetically determined in this species, but correlative models of observed vertebral counts and climate reveal that SST is the single strongest predictor of phenotype, even after accounting for gene flow. This result indicates that natural selection is responsible for maintaining vertebral clines in the silverside, and allows for the prediction of phenotypic responses to ocean warming. By integrating genetic estimates of population connectivity, species distribution models, and statistical models, I find that by the end of the 21st century, ocean warming will select for silversides with up to 8% fewer vertebrae. Mid-Atlantic populations are the most mal-adapted for future conditions, but may be rescued by migration from small-phenotype southern neighbors or by directional selection. Despite smaller temperature anomalies, the strongest impacts of warming will be felt at both northern and southern edges of the distribution, where genetic rescue from

Cold climate bioventing with soil warming in Alaska

International Nuclear Information System (INIS)

Sayles, G.D.; Brenner, R.C.; Leeson, A.; Hinchee, R.E.; Vogel, C.M.

1995-01-01

In the heart of Alaska, a 3-year field study was conducted of bioventing in conjunction with several soil warming methods. The contamination was JP-4 jet fuel. The soil warming methods evaluated, chosen for their apparent low cost, were (1) application of warm water at a low rate, (2) enhanced solar warming by covering the surface with clear plastic in the summer and covering the surface with insulation in the winter, and (3) buried heat pipe. The warm water and buried heat tape methods performed best, maintaining summer-like 10 to 20 C temperatures in the test plots year round, compared to the temperature of the unheated control plot, which dipped to -1 C in the winter. The solar/insulation warming method showed a modest improvement in temperature over the unheated control test plot. The annual average temperatures of the warm water, heat tape, solar, and control plots were 16.9, 14.5, 6.1, and 3.5 C, respectively. The biodegradation rates, measured by in situ respirometry, were higher in plots with higher temperatures and followed the Arrhenius relationship. Despite the low temperature, significant biodegradation was observed in the unheated plot during the winter

Fluctuations and trends in structure of fish community in Koporskaya Bay coastal waters (Gulf of Finland, Baltic Sea) and influence of water-intake facilities of the Leningrad nuclear power plant on fish fauna

International Nuclear Information System (INIS)

Zimin, V.L.

1996-01-01

The investigation is based on data obtained in 1978-1995 in Koporskaya Bay (eastern part of the Gulf of Finland), known as the cooling water-body of Leningrad (St. Petersburg) nuclear power plant Leningrad (NPP). 45 fish species were recorded in this period. The fish species diversity reduced significantly in last decade (from 8-9 in early 1980s up to 4-5 species in the nucleus of fish community in 1990s). Most vulnerable species, such as salmonids and coregonids, tend to disappear. Koporskaya Bay coastal area is now dominated by abundant three-spined and nine-spined sticklebacks. However, the relatively improved situation have occurred after beginning of reparation works at the 1st reactor unit, when the thermal loading was declined significantly. Great amount of fishes were perished at the water-intake facilities (more than 400 ton/year, in average). Changes in fish community structure caused noticeable changes in commercial fishing: the average percentage part of baltic herring (main object of fishing in the eastern Gulf of Finland) in commercial catches ranged from 90 up to 98% in the time before the LNPP started in operating, but from 1975, especially in last decade when LNPP has reached their project electrical capacity in 1981, we can see significant variations in herring's share (29-80%) in catches

Getting "boater" all the time: managing fishing by boat on New York city water supply reservoirs

Science.gov (United States)

Jennifer A. Cairo

2007-01-01

In 2003 the New York City Department of Environmental Protection Bureau of Water Supply undertook a five-year initiative to improve fishing by boat on its Water Supply reservoirs and controlled lakes in upstate New York. The project includes cleanup of administrative procedures and boat fishing areas on reservoir shores; improving two-way communication with anglers;...

Patterns of fish diversity and assemblage structure and water quality in the longest Asian tropical river (Mekong)

Science.gov (United States)

Chea, R.; Lek, S.; Grenouillet, G.

2016-12-01

Although the Mekong River is one of the world's 35 biodiversity hotspots, the large-scale patterns of fish diversity and assemblage structure remain poorly addressed. The present study aimed to investigate the spatial variability of water quality in the Lower Mekong Basin and the fish distribution patterns in the Lower Mekong River (LMR) and to identify their environmental determinants. Daily fish catch data at 38 sites distributed along the LMR were related to 15 physicochemical and 19 climatic variables. As a result, four different clusters were defined according to the similarity in assemblage composition and 80 indicator species were identified. While fish species richness was highest in the Mekong delta and lowest in the upper part of the LMR, the diversity index was highest in the middle part of the LMR and lowest in the delta. We found that fish assemblages changed along the environmental gradients and that the main drivers affecting the fish assemblage structure were the seasonal variation of temperature, precipitation, dissolved oxygen, pH, and total phosphorus. Specifically, upstream assemblages were characterized by cyprinids and Pangasius catfish, well suited to low temperature, high dissolved oxygen and high pH. Fish assemblages in the delta were dominated by perch-like fish and clupeids, more tolerant to high temperatures, and high levels of nutrients (nitrates and total phosphorus) and salinity. Overall, the patterns were consistent between seasons. Our study contributes to establishing the first holistic fish community study in the LMR. Overall of the LMR water quality, we found that the water in the mainstream was less polluted than its tributaries; eutrophication and salinity could be key factors affecting water quality in LMR. Moreover, the seasonal variation of water quality seemed to be less marked than spatial variation occurring along the longitudinal gradient of Mekong River. Significant degradations were mainly associated with human

Benthic macroinvertebrates as bioindicators of water quality in Billings Reservoir fishing sites (SP, Brazil

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José Ricardo Baroldi Ciqueto Gargiulo

Full Text Available Abastract: Aim The Billings Reservoir is the largest reservoir in the metropolitan region of São Paulo and has multiple uses, including artisanal fishing. Its surroundings present intense occupation, resulting in various environmental impacts. Although the water is degraded, affecting the composition and quality of the fish, this reservoir supports artisanal fishermen who survive through this activity. This study aimed to analyze the water quality in the main sites of artisanal fishing activity, with an emphasis on the benthic community as a bioindicator. Methods Three sampling sites were selected, in which water and zoobenthos samples were collected monthly from April 2012 to March 2013. Water analyses consisted of the determination of pH, temperature, conductivity, turbidity, total dissolved solids, dissolved oxygen, total nitrogen, total phosphorus, and trophic state as well as a principal components analysis. The zoobenthos analysis consisted of determining the relative abundance and total density of taxa, the Shannon-Weaver diversity index, taxa richness, uniformity, Simpson’s dominance index, and the benthic community index and conducting a canonical correspondence analysis. The non-parametric Kruskal-Wallis test followed by the Student-Newman-Keuls test were used to investigate the existence of significant differences in the abiotic and biotic variables among the sites. Results The studied sites showed a high degree of eutrophication, with nitrogen and phosphorus totals levels above the limits defined by current Brazilian legislation. Taquacetuba (P1 showed the best environmental conditions for the development of fishing activity, with the presence of sensitive organisms (Polymitarcyidae and higher levels of dissolved oxygen. Alvarenga (P2 had the worst water quality, with a predominance of tolerant organisms (Oligochaeta and lower levels of dissolved oxygen. Conclusion In conclusion, the benthic community in association with abiotic

Characterization of the quality of water, bed sediment, and fish in Mittry Lake, Arizona, 2014–15

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Hermosillo, Edyth; Coes, Alissa L.

2017-03-01

Water, bed-sediment, and fish sampling was conducted in Mittry Lake, Arizona, in 2014–15 to establish current water-quality conditions of the lake. The parameters of temperature, dissolved-oxygen concentration, specific conductance, and alkalinity were measured in the field. Water samples were collected and analyzed for dissolved major ions, dissolved trace elements, dissolved nutrients, dissolved organic carbon, dissolved pesticides, bacteria, and suspended-sediment concentrations. Bed-sediment and fish samples were analyzed for trace elements, halogenated compounds, total mercury, and methylmercury.U.S. Environmental Protection Agency secondary maximum contaminant levels in drinking water were exceeded for sulfate, chloride, and manganese in the water samples. Trace-element concentrations were relatively similar between the inlet, middle, and outlet locations. Concentrations for nutrients in all water samples were below the Arizona Department of Environmental Quality’s water-quality standards for aquatic and wildlife uses, and all bacteria levels were below the Arizona Department of Environmental Quality’s recommended recreational water-quality criteria. Three out of 81 pesticides were detected in the water samples.Trace-element concentrations in bed sediment were relatively consistent between the inlet, middle, and outlet locations. Lead, manganese, nickel, and zinc concentrations, however, decreased from the inlet to outlet locations. Concentrations for lead, nickel, and zinc in some bed-sediment samples exceeded consensus-based sediment-quality guidelines probable effect concentrations. Eleven out of 61 halogenated compounds were detected in bed sediment at the inlet location, whereas three were detected at the middle location, and five were detected at the outlet location. No methylmercury was detected in bed sediment. Total mercury was detected in bed sediment at concentrations below the consensus-based sediment-quality guidelines probable effect

Combined effects of water stress and pollution on macroinvertebrate and fish assemblages in a Mediterranean intermittent river.

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Kalogianni, Eleni; Vourka, Aikaterini; Karaouzas, Ioannis; Vardakas, Leonidas; Laschou, Sofia; Skoulikidis, Nikolaos Th

2017-12-15

Water stress is a key stressor in Mediterranean intermittent rivers exacerbating the negative effects of other stressors, such as pollutants, with multiple effects on different river biota. The current study aimed to determine the response of macroinvertebrate and fish assemblages to instream habitat and water chemistry, at the microhabitat scale and at different levels of water stress and pollution, in an intermittent Mediterranean river. Sampling was conducted at high and low summer discharge, at two consecutive years, and included four reaches that were targeted for their different levels of water stress and pollution. Overall, the macroinvertebrate fauna of Evrotas River indicated high resilience to intermittency, however, variation in community structure and composition occurred under acute water stress, due to habitat alteration and change in water physico-chemistry, i.e. water temperature increase. The combined effects of pollution and high water stress had, however, pronounced effects on species richness, abundance and community structure in the pollution impacted reach, where pollution sensitive taxa were almost extirpated. Fish response to drought, in reaches free of pollution, consisted of an increase in the abundance of the two small limnophilic species, coupled with their shift to faster flowing riffle habitats, and a reduction in the abundance of the larger, rheophilic species. In the pollution impacted reach, however, the combination of pollution and high water stress led to hypoxic conditions assumed to be the leading cause of the almost complete elimination of the fish assemblage. In contrast, the perennial Evrotas reaches with relatively stable physicochemical conditions, though affected hydrologically by drought, appear to function as refugia for fish during high water stress. When comparing the response of the two biotic groups to combined acute water stress and pollution, it is evident that macroinvertebrates were negatively impacted, but fish

The Effects of Ribose on Mechanical and Physicochemical Properties of Cold Water Fish Gelatin Films

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Neda Javadian

2014-06-01

Full Text Available Native fish gelatin has some disadvantages such as high hydrophilic, and solubility in cold water. Mixing with other biopolymers and crosslinking by sugars may improve functional properties of fish gelatin. So in this research, the effects of ribose were investigated on moisture sorption isotherm, solubility in water, and mechanical properties of cold water fish gelatin (CWFG films. Ribose sugar was incorporated into CWFG solutions at different concentrations (e.g. 0, 2, 4, and 6% w/w dried gelatin. Physicochemical properties such as water solubility, moisture sorption isotherm and mechanical properties of the films were measured according to ASTM standards. Results showed that incorporation of ribose sugar significantly improved functional properties of CWFG films. Solubility, moisture content and monolayer water content of the matrixes were decreased by increasing the ribose contents. Mechanical properties of biocomposites were improved more than 20% and moisture sorption isotherm curve significantly shifted to lower moisture contents. The results of this study could be explored for commercial use, depending on industrial needs for either production of edible films or for packaging purposes.

Effects of reservoirs water level variations on fish recruitment

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Fabíula T. de Lima

2017-10-01

Full Text Available ABSTRACT The construction of hydroelectric power plants has many social and environmental impacts. Among them, the impacts on fish communities, which habitats are drastically modified by dams, with consequences across the ecosystem. This study aimed to assess the influence of water level (WL variations in the reservoirs of the Itá and Machadinho hydroelectric plants on the recruitment of fish species from the upper Uruguay River in southern Brazil. The data analyzed resulted from the WL variation produced exclusively by the hydroelectric plants generation and were collected between the years 2001 and 2012. The results showed significant correlations between the abundance of juvenile fish and the hydrological parameters only for some reproductive guilds. The species that spawn in nests showed, in general, a clear preference for the stability in the WL of the reservoirs, while the species that spawn in macrophytes or that release demersal eggs showed no significant correlation between the abundance of juvenile fish and hydrological parameters. A divergence of results between the two reservoirs was observed between the species that release semi-dense eggs; a positive correlation with a more stable WL was only observed in the Machadinho reservoir. This result can be driven by a wider range of WL variation in Machadinho reservoir.

Biochemical responses in freshwater fish after exposure to water-soluble fraction of gasoline.

Science.gov (United States)

Bettim, Franciele Lima; Galvan, Gabrieli Limberger; Cestari, Marta Margarete; Yamamoto, Carlos Itsuo; de Assis, Helena Cristina Silva

2016-02-01

The water-soluble fraction of gasoline (WSFG) is a complex mixture of mono-polycyclic aromatic hydrocarbons. The study aimed to evaluate the effects of WSFG diluted 1.5% on freshwater fish. Astyanax altiparanae were exposed to the WSFG for 96 h, under a semi-static system, with renewal of 25% of the gasoline test solution every 24 h. In addition, a decay of the contamination (DC) was carried out. During DC, the fish was exposed to the WSFG for 8 d, followed by another 7 d with renewal of 25% of volume aquaria with clean water every 24 h. For depuration, fish were transferred to aquaria with clean water, and in addition, 25% of the water was replaced every 24 h. The liver and kidney biotransformation, antioxidant defenses and lipid peroxidation (LPO) levels were evaluated. In the liver, the WSFG 1.5% caused reduction of glutathione S-transferase (GST) after 96 h and DC. In the kidney, only in depuration an increased GST activity was observed, and after DC a higher LPO levels. An increase of the superoxide dismutase (SOD) activity occurred at 96 h in both tissues; however, in the liver was also observed during the depuration. In WSFG 96 h, the glutathione peroxidase (GPx) activity in the kidney increased. As biomarkers of neurotoxicity, the brain and muscle acetylcholinesterase activities were measured, but the WSFG 1.5% did not change them. Therefore, this study brought forth more data about WSFG effects on freshwater fish after lower concentrations exposure and a DC, simulating an environmental contamination. Copyright © 2015. Published by Elsevier Ltd.

The genetic mineralogical characteristics of fish otoliths and their ...

African Journals Online (AJOL)

DR NJ TONUKARI

2011-05-23

May 23, 2011 ... otoliths and their environmental typomorphism. Li Shengrong1* ... effectively to classify the species, trace the source, migration habits, nutrition level of the fish and the .... Pacific in response to the global warming events (Welch,. 1998). .... fishes. In Climate Change in Continental Isotopic Records (Edited by.

Effect of water velocity on intermediary metabolism of juvenile matrinxã fish (Brycon amazonicus)

OpenAIRE

Arbeláez-Rojas, Gustavo Alberto; Moraes, Gilberto

2013-01-01

Background: determination of water velocity for optimum fish growth is fundamental since its duration and intensity can interfere with the metabolic preference for some biochemical paths, resulting in the use of specific substrates for fish growth. Objective: the purpose of this study was to assess the metabolic adjustments of juvenile matrinxã (Brycon amazonicus) reared under various sustained swimming conditions (SS). Methods: fish were subjected to SS for 90 days at five swimming speeds: 0...

Skeletal stiffening in an amphibious fish out of water is a response to increased body weight.

Science.gov (United States)

Turko, Andy J; Kültz, Dietmar; Fudge, Douglas; Croll, Roger P; Smith, Frank M; Stoyek, Matthew R; Wright, Patricia A

2017-10-15

Terrestrial animals must support their bodies against gravity, while aquatic animals are effectively weightless because of buoyant support from water. Given this evolutionary history of minimal gravitational loading of fishes in water, it has been hypothesized that weight-responsive musculoskeletal systems evolved during the tetrapod invasion of land and are thus absent in fishes. Amphibious fishes, however, experience increased effective weight when out of water - are these fishes responsive to gravitational loading? Contrary to the tetrapod-origin hypothesis, we found that terrestrial acclimation reversibly increased gill arch stiffness (∼60% increase) in the amphibious fish Kryptolebias marmoratus when loaded normally by gravity, but not under simulated microgravity. Quantitative proteomics analysis revealed that this change in mechanical properties occurred via increased abundance of proteins responsible for bone mineralization in other fishes as well as in tetrapods. Type X collagen, associated with endochondral bone growth, increased in abundance almost ninefold after terrestrial acclimation. Collagen isoforms known to promote extracellular matrix cross-linking and cause tissue stiffening, such as types IX and XII collagen, also increased in abundance. Finally, more densely packed collagen fibrils in both gill arches and filaments were observed microscopically in terrestrially acclimated fish. Our results demonstrate that the mechanical properties of the fish musculoskeletal system can be fine-tuned in response to changes in effective body weight using biochemical pathways similar to those in mammals, suggesting that weight sensing is an ancestral vertebrate trait rather than a tetrapod innovation. © 2017. Published by The Company of Biologists Ltd.

Growth strategies and threshold responses to water deficit modulate effects of warming on tree seedlings from forest to alpine

Science.gov (United States)

Lazarus, Brynne E.; Castanha, Cristina; Germino, Matthew; Kueppers, Lara M.; Moyes, Andrew B.

2018-01-01

1.Predictions of upslope range shifts for tree species with warming are based on assumptions of moisture stress at lower elevation limits and low temperature stress at high elevation limits. However, recent studies have shown that warming can reduce tree seedling establishment across the entire gradient from subalpine forest to alpine via moisture limitation. Warming effects also vary with species, potentially resulting in community shifts in high elevation forests. 2.We examined the growth and physiology underlying effects of warming on seedling demographic patterns. We evaluated dry mass (DM), root length, allocation above- and belowground, and relative growth rate (RGR) of whole seedlings, and their ability to avoid or endure water stress via water-use efficiency and resisting turgor loss, for Pinus flexilis, Picea engelmannii and Pinus contorta seeded below, at, and above treeline in experimentally warmed, watered, and control plots in the Rocky Mountains, USA. We expected that growth and allocation responses to warming would relate to moisture status and that variation in drought tolerance traits would explain species differences in survival rates. 3.Across treatments and elevations, seedlings of all species had weak turgor-loss resistance, and growth was marginal with negative RGR in the first growth phase (-0.01 to -0.04 g/g/d). Growth was correlated with soil moisture, particularly in the relatively small-seeded P. contorta and P. engelmannii. P. flexilis, known to have the highest survivorship, attained the greatest DM and longest root but was also the slowest growing and most water-use-efficient. This was likely due to its greater reliance on seed reserves. Seedlings developed 15% less total DM, 25% less root DM, and 11% shorter roots in heated compared to unheated plots. Higher temperatures slightly increased DM, root length and RGR where soils were wettest, but more strongly decreased these variables under drier conditions. 4.Synthesis: The surprising

Lime application methods, water and bottom soil acidity in fresh water fish ponds

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Queiroz Julio Ferraz de

2004-01-01

Full Text Available Although some methods for determining lime requirement of pond soils are available and commonly used, there is still no consensus on whether it is more effective to apply liming materials to the bottoms of empty ponds or to wait and apply them over the water surface after ponds are filled. There is also little information on how deep lime reacts in pond sediment over time, and whether the depth of reaction is different when liming materials are applied to the water or to the soil. Therefore, three techniques for treating fish ponds with agricultural limestone were evaluated in ponds with clayey soils at a commercial fish farm. Amounts of agricultural limestone equal to the lime requirement of bottom soils were applied to each of three ponds by: direct application over the pond water surface; spread uniformly over the bottom of the empty pond; spread uniformly over the bottom of the empty pond followed by tilling of the bottom. Effectiveness of agricultural limestone applications did not differ among treatment methods. Agricultural limestone also reacted quickly to increase total alkalinity and total hardness of pond water to acceptable concentrations within 2 weeks after application. The reaction of lime to increase soil pH was essentially complete after one to two months, and lime had no effect below a soil depth of 8 cm. Tilling of pond bottoms to incorporate liming materials is unnecessary, and tilling consumes time and is an expensive practice; filled ponds can be limed effectively.

Rapid response of hydrological loss of DOC to water table drawdown and warming in Zoige peatland: results from a mesocosm experiment.

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Lou, Xue-Dong; Zhai, Sheng-Qiang; Kang, Bing; Hu, Ya-Lin; Hu, Li-Le

2014-01-01

A large portion of the global carbon pool is stored in peatlands, which are sensitive to a changing environment conditions. The hydrological loss of dissolved organic carbon (DOC) is believed to play a key role in determining the carbon balance in peatlands. Zoige peatland, the largest peat store in China, is experiencing climatic warming and drying as well as experiencing severe artificial drainage. Using a fully crossed factorial design, we experimentally manipulated temperature and controlled the water tables in large mesocosms containing intact peat monoliths. Specifically, we determined the impact of warming and water table position on the hydrological loss of DOC, the exported amounts, concentrations and qualities of DOC, and the discharge volume in Zoige peatland. Our results revealed that of the water table position had a greater impact on DOC export than the warming treatment, which showed no interactive effects with the water table treatment. Both DOC concentration and discharge volume were significantly increased when water table drawdown, while only the DOC concentration was significantly promoted by warming treatment. Annual DOC export was increased by 69% and 102% when the water table, controlled at 0 cm, was experimentally lowered by -10 cm and -20 cm. Increases in colored and aromatic constituents of DOC (measured by Abs(254 nm), SUVA(254 nm), Abs(400 nm), and SUVA(400 nm)) were observed under the lower water tables and at the higher peat temperature. Our results provide an indication of the potential impacts of climatic change and anthropogenic drainage on the carbon cycle and/or water storage in a peatland and simultaneously imply the likelihood of potential damage to downstream ecosystems. Furthermore, our results highlight the need for local protection and sustainable development, as well as suggest that more research is required to better understand the impacts of climatic change and artificial disturbances on peatland degradation.

Rapid response of hydrological loss of DOC to water table drawdown and warming in Zoige peatland: results from a mesocosm experiment.

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Xue-Dong Lou

Full Text Available A large portion of the global carbon pool is stored in peatlands, which are sensitive to a changing environment conditions. The hydrological loss of dissolved organic carbon (DOC is believed to play a key role in determining the carbon balance in peatlands. Zoige peatland, the largest peat store in China, is experiencing climatic warming and drying as well as experiencing severe artificial drainage. Using a fully crossed factorial design, we experimentally manipulated temperature and controlled the water tables in large mesocosms containing intact peat monoliths. Specifically, we determined the impact of warming and water table position on the hydrological loss of DOC, the exported amounts, concentrations and qualities of DOC, and the discharge volume in Zoige peatland. Our results revealed that of the water table position had a greater impact on DOC export than the warming treatment, which showed no interactive effects with the water table treatment. Both DOC concentration and discharge volume were significantly increased when water table drawdown, while only the DOC concentration was significantly promoted by warming treatment. Annual DOC export was increased by 69% and 102% when the water table, controlled at 0 cm, was experimentally lowered by -10 cm and -20 cm. Increases in colored and aromatic constituents of DOC (measured by Abs(254 nm, SUVA(254 nm, Abs(400 nm, and SUVA(400 nm were observed under the lower water tables and at the higher peat temperature. Our results provide an indication of the potential impacts of climatic change and anthropogenic drainage on the carbon cycle and/or water storage in a peatland and simultaneously imply the likelihood of potential damage to downstream ecosystems. Furthermore, our results highlight the need for local protection and sustainable development, as well as suggest that more research is required to better understand the impacts of climatic change and artificial disturbances on peatland degradation.

An Optimization Scheme for Water Pump Control in Smart Fish Farm with Efficient Energy Consumption

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Israr Ullah

2018-06-01

Full Text Available Healthy fish production requires intensive care and ensuring stable and healthy production environment inside the farm tank is a challenging task. An Internet of Things (IoT based automated system is highly desirable that can continuously monitor the fish tanks with optimal resources utilization. Significant cost reduction can be achieved if farm equipment and water pumps are operated only when required using optimization schemes. In this paper, we present a general system design for smart fish farms. We have developed an optimization scheme for water pump control to maintain desired water level in fish tank with efficient energy consumption through appropriate selection of pumping flow rate and tank filling level. Proposed optimization scheme attempts to achieve a trade-off between pumping duration and flow rate through selection of optimized water level. Kalman filter algorithm is applied to remove error in sensor readings. We observed through simulation results that optimization scheme achieve significant reduction in energy consumption as compared to the two alternate schemes, i.e., pumping with maximum and minimum flow rates. Proposed system can help in collecting the data about the farm for long-term analysis and better decision making in future for efficient resource utilization and overall profit maximization.

Herbivory of Omnivorous Fish Shapes the Food Web Structure of a Chinese Tropical Eutrophic Lake: Evidence from Stable Isotope and Fish Gut Content Analyses

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Jian Gao

2017-01-01

Full Text Available Studies suggest that, unlike the situation in temperate lakes, high biomasses of omnivorous fish are maintained in subtropical and tropical lakes when they shift from a turbid phytoplankton-dominated state to a clear water macrophyte-dominated state, and the predation pressure on large-bodied zooplankton therefore remains high. Whether this reflects a higher degree of herbivory in warm lakes than in temperate lakes is debatable. We combined food web studies using stable isotopes with gut content analyses of the most dominant fish species to elucidate similarities and differences in food web structure between a clear water macrophyte-dominated basin (MDB and a turbid phytoplankton-dominated basin (PDB of Huizhou West Lake, a shallow tropical Chinese lake. The δ13C–δ15N biplot of fish and invertebrates revealed community-wide differences in isotope-based metrics of the food webs between MDB and PDB. The range of consumer δ15N (NR was lower in MDB than in PDB, indicating shorter food web length in MDB. The mean nearest neighbor distance (MNND and standard deviation around MNND (SDNND were higher in MDB than in PDB, showing a markedly low fish trophic overlap and a more uneven packing of species in niches in MDB than in PDB. The range of fish δ13C (CR of consumers was more extensive in MDB than in PDB, indicating a wider feeding range for fish in MDB. Mixing model results showed that macrophytes and associated periphyton constituted a large fraction of basal production sources for the fish in MDB, while particulate organic matter (POM contributed a large fraction in PDB. In MDB, the diet of the dominant fish species, crucian carp (Carassius carassius, consisted mainly of vegetal matter (macrophytes and periphyton and zooplankton, while detritus was the most important food item in PDB. Our results suggest that carbon from macrophytes with associated periphyton may constitute an important food resource for omnivorous fish, and this may strongly

Flowing water affects fish fast-starts: escape performance of the Hawaiian stream goby, Sicyopterus stimpsoni.

Science.gov (United States)

Diamond, Kelly M; Schoenfuss, Heiko L; Walker, Jeffrey A; Blob, Richard W

2016-10-01

Experimental measurements of escape performance in fishes have typically been conducted in still water; however, many fishes inhabit environments with flow that could impact escape behavior. We examined the influences of flow and predator attack direction on the escape behavior of fish, using juveniles of the amphidromous Hawaiian goby Sicyopterus stimpsoni In nature, these fish must escape ambush predation while moving through streams with high-velocity flow. We measured the escape performance of juvenile gobies while exposing them to a range of water velocities encountered in natural streams and stimulating fish from three different directions. Frequency of response across treatments indicated strong effects of flow conditions and attack direction. Juvenile S. stimpsoni had uniformly high response rates for attacks from a caudal direction (opposite flow); however, response rates for attacks from a cranial direction (matching flow) decreased dramatically as flow speed increased. Mechanical stimuli produced by predators attacking in the same direction as flow might be masked by the flow environment, impairing the ability of prey to detect attacks. Thus, the likelihood of successful escape performance in fishes can depend critically on environmental context. © 2016. Published by The Company of Biologists Ltd.

Potential impacts of climate warming on water supply reliability in the Tuolumne and Merced River Basins, California.

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Michael Kiparsky

Full Text Available We present an integrated hydrology/water operations simulation model of the Tuolumne and Merced River Basins, California, using the Water Evaluation and Planning (WEAP platform. The model represents hydrology as well as water operations, which together influence water supplied for agricultural, urban, and environmental uses. The model is developed for impacts assessment using scenarios for climate change and other drivers of water system behavior. In this paper, we describe the model structure, its representation of historical streamflow, agricultural and urban water demands, and water operations. We describe projected impacts of climate change on hydrology and water supply to the major irrigation districts in the area, using uniform 2 °C, 4 °C, and 6 °C increases applied to climate inputs from the calibration period. Consistent with other studies, we find that the timing of hydrology shifts earlier in the water year in response to temperature warming (5-21 days. The integrated agricultural model responds with increased water demands 2 °C (1.4-2.0%, 4 °C (2.8-3.9%, and 6 °C (4.2-5.8%. In this sensitivity analysis, the combination of altered hydrology and increased demands results in decreased reliability of surface water supplied for agricultural purposes, with modeled quantity-based reliability metrics decreasing from a range of 0.84-0.90 under historical conditions to 0.75-0.79 under 6 °C warming scenario.

Effects of elevated CO2 on predator avoidance behaviour by reef fishes is not altered by experimental test water

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Philip L. Munday

2016-10-01

Full Text Available Pioneering studies into the effects of elevated CO2 on the behaviour of reef fishes often tested high-CO2 reared fish using control water in the test arena. While subsequent studies using rearing treatment water (control or high CO2 in the test arena have confirmed the effects of high CO2 on a range of reef fish behaviours, a further investigation into the use of different test water in the experimental arena is warranted. Here, we used a fully factorial design to test the effect of rearing treatment water (control or high CO2 and experimental test water (control or high CO2 on antipredator responses of larval reef fishes. We tested antipredator behaviour in larval clownfish Amphiprion percula and ambon damselfish Pomacentrus amboinensis, two species that have been used in previous high CO2 experiments. Specifically, we tested if: (1 using control or high CO2 water in a two channel flume influenced the response of larval clownfish to predator odour; and (2 using control or high CO2 water in the test arena influenced the escape response of larval damselfish to a startle stimulus. Finally, (3 because the effects of high CO2 on fish behaviour appear to be caused by altered function of the GABA-A neurotransmitter we tested if antipredator behaviours were restored in clownfish treated with a GABA antagonist (gabazine in high CO2 water. Larval clownfish reared from hatching in control water (496 µatm strongly avoided predator cue whereas larval clownfish reared from hatching in high CO2 (1,022 µatm were attracted to the predator cue, as has been reported in previous studies. There was no effect on fish responses of using either control or high CO2 water in the flume. Larval damselfish reared for four days in high CO2 (1,051 µatm exhibited a slower response to a startle stimulus and slower escape speed compared with fish reared in control conditions (464 µatm. There was no effect of test water on escape responses. Treatment of high-CO2 reared

49 CFR 173.218 - Fish meal or fish scrap.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Fish meal or fish scrap. 173.218 Section 173.218... Fish meal or fish scrap. (a) Except as provided in Column (7) of the HMT in § 172.101 of this subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized for...

FRESHWATER FISH FARMING CONDITIONS IN 1999 AND THE PRODUCTION PLAN FOR 2000

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Zlatko Homen

2000-09-01

Full Text Available One of the activities of the Ministry of Agriculture and Forestry, Fishery and Mediterranean Agriculture Directorate, i. e. Fishery Directorate to be more specific, is the monitoring of conditions in freshwater fish farming. The objective of this work is to show conditions in freshwater fish farming during 1999. and to provide a production plan for 2000. It will also provide detailed insight into the present conditions in freshwater fish farming and into the production trends of this field. Regarding this issue, the »Questionnaire for the Monitoring of Conditions in Freshwater Fish Farming«, was sent to fish farmers aroud the country data was processed from 22 cap ponds and 13 trout ponds. Roughe estimates of conditions were conducted for 2 fish farms, since they haven’t yet returned the mandatoruy questionnaire, i. e. the necessary data. This work features data on the number of employees in fish farms, as well as their qualifications, on the actual production and distribution of farmed freshwater fish, on the areas where production was conducted and on the overall yield. Fish food, raw materials, used tools and incentive funds paid were also taken into consideration. The difficulties faced in this branch of the economy are also inicated. Compared to 1998, a slight decrease in the number of employees of freshwater fish farms has been recorded. The total number of employees in 1999 was 655, of which 555 were on carp ponds and 100 on trout ponds. Data on the qualifications of employees for 1999 show that most of them were unskilled workers, while highly skilled workers make up a minority in this work force. The total production of freshwater in 1999. amoounted to 6.185,51 tons. Of this amount 5.592,52 tons were warm-water fish specied and 592,99 tons were cold-water fish species. Compared to 1998, production decreased by 4,89 percent. Production for 2000 has been planned to increase by 22,15 percent, i. e. the production quantity is projected

Evaluation of Water Quality Conditions Near Proposed Fish Production Sites Associated with the Yakima Fisheries Project, 1991-1993 Final Report.

Energy Technology Data Exchange (ETDEWEB)

Dauble, Dennis D.

1994-05-01

In 1991, the Pacific Northwest Laboratory (PNL) began studying water quality at several sites in the Yakima River Basin for the Bonneville Power Administration. These sites were being proposed as locations for fish culture facilities as part of the Yakima Fisheries Project (YFP). Surface water quality parameters near the proposed fish culture facilities are currently suitable for fish production. Water quality conditions in the mainstream Yakima River and its tributaries are generally excellent in the upper part of the watershed (i.e., near Cle Elum), but they are only fair to poor for the river downstream of Union Gap (river mile 107). Water quality of the Naches River near Oak Flats is also suitable for fish production. Groundwater supplies near the proposed fish production facilities typically have elevated concentrations of metals and dissolved gases. These conditions can be mitigated using best engineering practices such as precipitation and degasification. Additionally, mixing with surface water may improve these conditions. Depending on the location and depth of the well, groundwater temperatures may be warmer than optimum for acclimating and holding juvenile and adult fish. Water quality parameters measured in the Yakima River and tributaries sometimes exceed the range of values described as acceptable for culture of salmonids and for the protection of other aquatic life. However, constituent concentrations are within ranges that exist in many northwest fish hatcheries. Additionally, site-specific tests conducted by PNL (i.e., live box exposures and egg incubation studies) indicate that fish can be successfully reared in surface and well water near the proposed facility sites. Thus, there appear to be no constraints to artificial production for the YFP.

Acute thermal tolerance of tropical estuarine fish occupying a man-made tidal lake, and increased exposure risk with climate change

Science.gov (United States)

Waltham, Nathan J.; Sheaves, Marcus

2017-09-01

Understanding acute hyperthermic exposure risk to animals, including fish in tropical estuaries, is increasingly necessary under future climate change. To examine this hypothesis, fish (upper water column species - glassfish, Ambassis vachellii; river mullet, Chelon subviridis; diamond scale mullet, Ellochelon vaigiensis; and ponyfish, Leiognathus equulus; and lower water bottom dwelling species - whiting Sillago analis) were caught in an artificial tidal lake in tropical north Queensland (Australia), and transported to a laboratory tank to acclimate (3wks). After acclimation, fish (between 10 and 17 individuals each time) were transferred to a temperature ramping experimental tank, where a thermoline increased (2.5 °C/hr; which is the average summer water temperature increasing rate measured in the urban lakes) tank water temperature to establish threshold points where each fish species lost equilibrium (defined here as Acute Effect Temperature; AET). The coolest AET among all species was 33.1 °C (S. analis), while the highest was 39.9 °C (A. vachellii). High frequency loggers were deployed (November and March representing Austral summer) in the same urban lake where fish were sourced, to measure continuous (20min) surface (0.15 m) and bottom (0.1 m) temperature to derive thermal frequency curves to examine how often lake temperatures exceed AET thresholds. For most fish species examined, water temperature that could be lethal were exceeded at the surface, but rarely, if ever, at the bottom waters suggesting deep, cooler, water provides thermal refugia for fish. An energy-balance model was used to estimate daily mean lake water temperature with good accuracy (±1 °C; R2 = 0.91, modelled vs lake measured temperature). The model was used to predict climate change effects on lake water temperature, and the exceedance of thermal threshold change. A 2.3 °C climate warming (based on 2100 local climate prediction) raised lake water temperature by 1.3 °C. However

Phase II Water Rental Pilot Project: Snake River Resident Fish and Wildlife Resources and Management Recommendations.

Energy Technology Data Exchange (ETDEWEB)

Stovall, Stacey H.

1994-08-01

The Idaho Water Rental Pilot Project was implemented in 1991 as part of the Non-Treaty Storage Fish and Wildlife Agreement between Bonneville Power Administration and the Columbia Basin Fish and Wildlife Authority. The goal of the project is to quantify resident fish and wildlife impacts resulting from salmon flow augmentation releases made from the upper Snake River Basin. Phase I summarized existing resource information and provided management recommendations to protect and enhance resident fish and wildlife habitat resulting from storage releases for the I improvement of an adromous fish migration. Phase II includes the following: (1) a summary of recent biological, legal, and political developments within the basin as they relate to water management issues, (2) a biological appraisal of the Snake River between American Falls Reservoir and the city of Blackfoot to examine the effects of flow fluctuation on fish and wildlife habitat, and (3) a preliminary accounting of 1993--1994 flow augmentation releases out of the upper Snake, Boise, and Payette river systems. Phase III will include the development of a model in which annual flow requests and resident fish and wildlife suitability information are interfaced with habitat time series analysis to provide an estimate of resident fish and wildlife resources.

Surface water connectivity drives richness and composition of Arctic lake fish assemblages

Science.gov (United States)

Laske, Sarah M.; Haynes, Trevor B.; Rosenberger, Amanda E.; Koch, Joshua C.; Wipfli, Mark S.; Whitman, Matthew; Zimmerman, Christian E.

2016-01-01

Surface water connectivity can influence the richness and composition of fish assemblages, particularly in harsh environments where colonisation factors and access to seasonal refugia are required for species persistence.

Heavy Metals (Cu, Pb and Cd) in Water and Angel Fish (Chelmon rostractus) from Batam Coastal, Indonesia

OpenAIRE

Ismarti Ismarti; Ramses Ramses; Suheryanto Suheryanto; Fitrah Amelia

2017-01-01

Fish play an important role in human nutrition and therefore need to be carefully and routinely monitored to ensure that there are no high levels of heavy metals being transferred to human through their consumption. This study has been carried out to determine level of heavy metals (Cu, Pb, and Cd) in water and angel fish, Chelmon rostractus collected from coast of Batam. We report levels of Cu, Cd and Pb in water and angel fish from Coast Batam using Atomic Absorption Spectroscopy (AAS). Lev...

Radioactivity of surface water and freshwater fish in Finland in 1988-1990

International Nuclear Information System (INIS)

Saxen, R.; Koskelainen, U.

1992-02-01

Changes over time in the activity concentrations of radionuclides in surface water and in the five largest rivers and some smaller rivers discharging into the Baltic Sea were monitored in 1988-1990. The dominant gamma-emitting radionuclides were 137 Cs and 134 Cs. The effect of the uneven distribution of Chernobyl deposition is still seen in the results. The activity concentrations of 137 Cs in surface water have decreased significantly: In the drainage area where the activity concentrations were highest after the Chernobyl accident, the concentrations in October 1990 were only about 1-4% of the maximum values in May 1986. The decrease in the activity concentrations of 90 Sr was much slighter. The study of areal and temporal changes in the activity concentrations of 137 Cs in fish, started in 1986, continued in 1988-1990. In all, about 2400 fish samples from southern and middle Finland (excluding Lappland) were analyzed gammaspectrometrially during these three years. Seventeen different fish species were included in the study. (20 refs., 14 figs., 30 tabs.)

Potentials and challenges of biogas from fish industry waste in the Arctic

DEFF Research Database (Denmark)

Jensen, Pernille Erland; Heiske, Stefan

2016-01-01

The fish industry is a main industry in many Arctic locations. In most places by-products are disposed of at sea. Oxygen depletion and dead sea bottom is observed, as the organic material is biodegraded and methane produced; contributing to the global warming. In this study, the biogas potential...... of indicator microorganisms was investigated. All residues had biogas potentials similar to or higher than conventional feedstocks like manure and silage. Waste water sludge and brown algae had potentials comparable to manure. The combined shrimp and algae digestion showed indication of synergistic effects...

Global lake response to the recent warming hiatus

Science.gov (United States)

Winslow, Luke A.; Leach, Taylor H.; Rose, Kevin C.

2018-05-01

Understanding temporal variability in lake warming rates over decadal scales is important for understanding observed change in aquatic systems. We analyzed a global dataset of lake surface water temperature observations (1985‑2009) to examine how lake temperatures responded to a recent global air temperature warming hiatus (1998‑2012). Prior to the hiatus (1985‑1998), surface water temperatures significantly increased at an average rate of 0.532 °C decade‑1 (±0.214). In contrast, water temperatures did not change significantly during the hiatus (average rate ‑0.087 °C decade‑1 ±0.223). Overall, 83% of lakes in our dataset (129 of 155) had faster warming rates during the pre-hiatus period than during the hiatus period. These results demonstrate that lakes have exhibited decadal-scale variability in warming rates coherent with global air temperatures and represent an independent line of evidence for the recent warming hiatus. Our analyses provide evidence that lakes are sentinels of broader climatological processes and indicate that warming rates based on datasets where a large proportion of observations were collected during the hiatus period may underestimate longer-term trends.

Relative contributions of food and water in the accumulation of 60Co by a freshwater fish

International Nuclear Information System (INIS)

Baudin, J.P.; Fritsch, A.F.

1989-01-01

Because of its presence in the natural environment a laboratory research program was undertaken with 60 Co, focused on a freshwater fish, Cyprinus carpio. In this paper results from laboratory experiments conducted to assess the role of food and water in the uptake and retention of 60 Co by the carp are reported. The 60 Co accumulation by the fish from water, from food and from both sources simultaneously were studied during the first phase. After this exposure phase the individuals are transferred to non-radioactive water and/or received unlabelled food to follow depuration of the radionuclide. There was no significant difference between the fish of the 3 treatment groups; the greatest fraction of residual radiocobalt resided in digestive tract that accounted for 20-25% of the total 69 Co body burden. (author)

Is the distribution of Prochlorococcus and Synechococcus ecotypes in the Mediterranean Sea affected by global warming?

Directory of Open Access Journals (Sweden)

M. Ostrowski

2011-09-01

Full Text Available Biological communities populating the Mediterranean Sea, which is situated at the northern boundary of the subtropics, are often claimed to be particularly affected by global warming. This is indicated, for instance, by the introduction of (subtropical species of fish or invertebrates that can displace local species. This raises the question of whether microbial communities are similarly affected, especially in the Levantine basin where sea surface temperatures have significantly risen over the last 25 years (0.50 ± 0.11 °C in average per decade, P Prochlorococcus and Synechococcus, was examined during two cruises through both eastern and western Mediterranean Sea basins held in September 1999 (PROSOPE cruise and in June–July 2008 (BOUM cruise. Diversity was studied using dot blot hybridization with clade-specific 16S rRNA oligonucleotide probes and/or clone libraries of the 16S-23S ribosomal DNA Internal Transcribed Spacer (ITS region, with a focus on the abundance of clades that may constitute bioindicators of warm waters. During both cruises, the dominant Prochlorococcus clade in the upper mixed layer at all stations was HLI, a clade typical of temperate waters, whereas the HLII clade, the dominant group in (subtropical waters, was only present at very low concentrations. The Synechococcus community was dominated by clades I, III and IV in the northwestern waters of the Gulf of Lions and by clade III and groups genetically related to clades WPC1 and VI in the rest of the Mediterranean Sea. In contrast, only a few sequences of clade II, a group typical of warm waters, were observed. These data indicate that local cyanobacterial populations have not yet been displaced by their (subtropical counterparts.

Effect of Warm Atlantic Waters on the Climate Anomalies in the West Arctic

Directory of Open Access Journals (Sweden)

A. N. Zolotokrylin

2015-01-01

Full Text Available Significant climatic changes of oceanic and atmospheric elements and a relation of them to the ocean surface winter anomalies in North Atlantic are analyzed in the paper. Periods of «warm» ocean (2002–2012 and «cold» ocean (1960–1970 were determined. Positive anomalies of the ocean surface temperature increase the ice-free water area and, correspondingly, decrease the ice-field area. As a result of such changes in a state of the ocean surface (open water and ice, surface air temperature rises, and, consequently, atmospheric pressure in central part of a given Arctic sector drops.

Sampling designs and methods for estimating fish-impingement losses at cooling-water intakes

International Nuclear Information System (INIS)

Murarka, I.P.; Bodeau, D.J.

1977-01-01

Several systems for estimating fish impingement at power plant cooling-water intakes are compared to determine the most statistically efficient sampling designs and methods. Compared to a simple random sampling scheme the stratified systematic random sampling scheme, the systematic random sampling scheme, and the stratified random sampling scheme yield higher efficiencies and better estimators for the parameters in two models of fish impingement as a time-series process. Mathematical results and illustrative examples of the applications of the sampling schemes to simulated and real data are given. Some sampling designs applicable to fish-impingement studies are presented in appendixes

Efficacy of sanitized ice in reducing bacterial load on fish fillet and in the water collected from the melted ice.

Science.gov (United States)

Feliciano, Lizanel; Lee, Jaesung; Lopes, John A; Pascall, Melvin A

2010-05-01

This study investigated the efficacy of sanitized ice for the reduction of bacteria in the water collected from the ice that melted during storage of whole and filleted Tilapia fish. Also, bacterial reductions on the fish fillets were investigated. The sanitized ice was prepared by freezing solutions of PRO-SAN (an organic acid formulation) and neutral electrolyzed water (NEW). For the whole fish study, the survival of the natural microflora was determined from the water of the melted ice prepared with PRO-SAN and tap water. These water samples were collected during an 8 h storage period. For the fish fillet study, samples were inoculated with Escherichia coli K12, Listeria innocua, and Pseudomonas putida then stored on crushed sanitized ice. The efficacies of these were tested by enumerating each bacterial species on the fish fillet and in the water samples at 12 and 24 h intervals for 72 h, respectively. Results showed that each bacterial population was reduced during the test. However, a bacterial reduction of fillet samples. A maximum of approximately 2 log CFU and > 3 log CFU reductions were obtained in the waters sampled after the storage of whole fish and the fillets, respectively. These reductions were significantly (P < 0.05) higher in the water from sanitized ice when compared with the water from the unsanitized melted ice. These results showed that the organic acid formulation and NEW considerably reduced the bacterial numbers in the melted ice and thus reduced the potential for cross-contamination.

The effects of periphyton, fish and fertilizer dose on biological processes affecting water quality in earthen fish ponds.

NARCIS (Netherlands)

Milstein, A.; Azim, M.E.; Wahab, M.A.; Verdegem, M.C.J.

2003-01-01

The potential of periphyton-based aquaculture in South Asia is under investigation in an extensive research program. This paper is a further analysis of data from four experiments carried out in that framework, to explore periphyton, fish and fertilizer dose effects on water quality. Factor analysis

The spatial distribution of silicoflagellates in the region of the Gulf Stream warm-core ring 82B: application to water mass tracer studies

Science.gov (United States)

Takahashi, Kozo; Blackwelder, Patricia L.

1992-03-01

To delineate potential water mass affinities, we investigated silicoflagellates from the region of Gulf Stream warm-core ring (WCR) 82B in the northwestern Atlantic. Silicoflagellates from 202 samples from N-S and an E-W transects across WCR 82B during late April were analysed. Shelf to Sargasso Sea transects, one completed in early May and the other in June 1982 were also examined. Eight to 11 vertical profiles to 200 m comprised each of the transects. Six taxa of silicoflagellates were found in the samples studied and a total of more than 8000 specimens were encountered. Three major taxa dominated standing stocks: Distephanus speculum, Dictyocha messanensis (intermediate-sized form) and D. mandrai. D. speculum, considered a cold-water taxon in the literature, showed a higher standing stock in the cooler high-velocity region (HVR) of the warm-core ring, continental shelf (SH) and slope (SL) waters. Fewer were present in the wanner ring center (RC), Gulf Stream (GS) and Sargasso Sea (SS). D. mandrai showed a similar distribution to that of D. speculum, but its preference for slightly warmer waters (>~10°C) was noted. In contrast, Dictyocha messanensis (intermediate-sized) and Distephanus pulchra, known to be warm-water taxa, were relatively abundant in the warm ring center. In contrast to standing stock data, ratios between cold- and warm-water taxa correlate well with temperature and salinity in the warm-core ring. Since these ratios are not effected by convective loss, they are excellent water mass tracers in this system. Distribution of the silicoflagellate taxa suggests that WCR82B April had a higher affinity with the Gulf Stream than the Sargasso Sea. Scores derived from factor analysis indicate that silicoflagellate species distributions are highly correlative with water masses. This was evident from correlations with temperature, salinity and with distance from ring center. Nutrients were generally not correlated with species data. This may be due to deep

Self-confidence of anglers in identification of freshwater sport fish

Science.gov (United States)

Chizinski, C.J.; Martin, D. R.; Pope, Kevin L.

2014-01-01

Although several studies have focused on how well anglers identify species using replicas and pictures, there has been no study assessing the confidence that can be placed in angler's ability to identify recreationally important fish. Understanding factors associated with low self-confidence will be useful in tailoring education programmes to improve self-confidence in identifying common species. The purposes of this assessment were to quantify the confidence of recreational anglers to identify 13 commonly encountered warm water fish species and to relate self-confidence to species availability and angler experience. Significant variation was observed in anglers self-confidence among species and levels of self-declared skill, with greater confidence associated with greater skill and with greater exposure. This study of angler self-confidence strongly highlights the need for educational programmes that target lower skilled anglers and the importance of teaching all anglers about less common species, regardless of skill level.

Recovery of Organic and Amino Acids from Sludge and Fish Waste in Sub Critical Water Conditions

Directory of Open Access Journals (Sweden)

Muhammad Faisal

2011-12-01

Full Text Available The possibility of organic and amino acid production from the treatment of sludge and fish waste using water at sub critical conditions was investigated. The results indicated that at sub-critical conditions, where the ion product of water went through a maximum, the formation of organic acids was favorable. The presence of oxidant favored formation of acetic and formic acid. Other organic acids of significant amount were propionic, succinic and lactic acids. Depending on the type of wastes, formation of other organic acids was also possible. Knowing the organic acids obtained by hydrolysis and oxidation in sub-critical water of various wastes are useful in designing of applicable waste treatment process, complete degradation of organic wastes into volatile carbon and water, and also on the viewpoint of resource recovery. The production of lactic acid was discussed as well. The results indicated that temperature of 573 K, with the absence of oxidant, yield of lactic acid from fish waste was higher than sewage sludge. The maximum yield of total amino acids (137 mg/g-dry fish from waste fish entrails was obtained at subcritical condition (T = 523 K, P = 4 MPa at reaction time of 60 min by using the batch reactor. The amino acids obtained in this study were mainly alanine and glycine. Keywords:  organic acids, amino acids, sub-critical water, hydrothermal, resources recovery

Global Warming: A Reduced Threat?.

Science.gov (United States)

Michaels, Patrick J.; Stooksbury, David E.

1992-10-01

One popular and apocalyptic vision of the world influenced by increasing concentrations of infrared-absorbing trace gases is that of ecological disaster brought about by rapidly rising temperatures, sea level, and evaporation rates. This vision developed from a suite of climate models that have since considerably changed in both their dynamics and their estimates of prospective warming. Observed temperatures indicate that much more warming should already have taken place than predicted by earlier models in the Northern Hemisphere, and that night, rather than day, readings in that hemisphere show a relative warming. A high-latitude polar-night warming or a general night warming could be either benign or beneficial. A large number of plant species show both increased growth and greater water-use efficiency under enhanced carbon dioxide.An extensive body of evidence now indicates that anthropo-generated sulfate emissions are mitigating some of the warming, and that increased cloudiness as a result of these emissions will further enhance night, rather than day, warming. The sulfate emissions, though, are not sufficient to explain all of the night warming. However, the sensitivity of climate to anthropogenerated aerosols, and the general lack of previously predicted warming, could drastically alter the debate on global warming in favor of less expensive policies.

Survival of fish upon removal of cyanide from water

International Nuclear Information System (INIS)

Gacsi, Mariann; Czegeny, Ildiko; Nagy, Gabor; Banfalvi, Gaspar

2005-01-01

The effects of potassium cyanide and the removal of cyanide from water in vivo on the survival of fish were investigated. This research was initiated because of the catastrophe that took place at the end of January 2000 in the Carpathian basin, when an enormous amount of cyanide pollution swept through the Samos and Tisza rivers, and then to the Danube. Since nothing was done against the disaster, we have suggested a chemical solution to remove cyanide from waterways (Chem. Innovat. 30 (2000b) 53). Based on experiments, we describe that the most effective and harmless way to remove cyanide and to save the lives of fish from 40 to 160x the lethal doses of cyanide is to use carbogen gas containing 5% carbon dioxide and 95% oxygen followed by aeration with air

Fish occurrence in the fishpass on the lowland section of the River Elbe, Czech Republic, with respect to water temperature, water flow and fish size

Czech Academy of Sciences Publication Activity Database

Prchalová, Marie; Horký, P.; Slavík, O.; Vetešník, Lukáš; Halačka, Karel

2011-01-01

Roč. 60, č. 2 (2011), s. 104-114 ISSN 0139-7893. [Česká ichtyologická konference /12./. Vodňany, 19.05.2010-20.05.2010] R&D Projects: GA AV ČR(CZ) 1QS500450513 Institutional research plan: CEZ:AV0Z60170517; CEZ:AV0Z60930519 Keywords : migration * fish * water flow * water temperature * fishpass Subject RIV: DA - Hydrology ; Limnology Impact factor: 0.554, year: 2011 http://www.ivb.cz/folia/60/2/050-2010.pdf

The risk of water scarcity at different levels of global warming

Science.gov (United States)

Schewe, Jacob; Sharpe, Simon

2015-04-01

Water scarcity is a threat to human well-being and economic development in many countries today. Future climate change is expected to exacerbate the global water crisis by reducing renewable freshwater resources different world regions, many of which are already dry. Studies of future water scarcity often focus on most-likely, or highest-confidence, scenarios. However, multi-model projections of water resources reveal large uncertainty ranges, which are due to different types of processes (climate, hydrology, human) and are therefore not easy to reduce. Thus, central estimates or multi-model mean results may be insufficient to inform policy and management. Here we present an alternative, risk-based approach. We use an ensemble of multiple global climate and hydrological models to quantify the likelihood of crossing a given water scarcity threshold under different levels of global warming. This approach allows assessing the risk associated with any particular, pre-defined threshold (or magnitude of change that must be avoided), regardless of whether it lies in the center or in the tails of the uncertainty distribution. We show applications of this method on the country and river basin scale, illustrate the effects of societal processes on the resulting risk estimates, and discuss the further potential of this approach for research and stakeholder dialogue.

Phenological and distributional shifts in ichthyoplankton associated with recent warming in the northeast Pacific Ocean.

Science.gov (United States)

Auth, Toby D; Daly, Elizabeth A; Brodeur, Richard D; Fisher, Jennifer L

2018-01-01

Understanding changes in the migratory and reproductive phenology of fish stocks in relation to climate change is critical for accurate ecosystem-based fisheries management. Relocation and changes in timing of reproduction can have dramatic effects upon the success of fish populations and throughout the food web. During anomalously warm conditions (1-4°C above normal) in the northeast Pacific Ocean during 2015-2016, we documented shifts in timing and spawning location of several pelagic fish stocks based on larval fish samples. Total larval concentrations in the northern California Current (NCC) during winter (January-March) 2015 and 2016 were the highest observed since annual collections first occurred in 1998, primarily due to increased abundances of Engraulis mordax (northern anchovy) and Sardinops sagax (Pacific sardine) larvae, which are normally summer spawning species in this region. Sardinops sagax and Merluccius productus (Pacific hake) exhibited an unprecedented early and northward spawning expansion during 2015-16. In addition, spawning duration was greatly increased for E. mordax, as the presence of larvae was observed throughout the majority of 2015-16, indicating prolonged and nearly continuous spawning of adults throughout the warm period. Larvae from all three of these species have never before been collected in the NCC as early in the year. In addition, other southern species were collected in the NCC during this period. This suggests that the spawning phenology and distribution of several ecologically and commercially important fish species dramatically and rapidly changed in response to the warming conditions occurring in 2014-2016, and could be an indication of future conditions under projected climate change. Changes in spawning timing and poleward migration of fish populations due to warmer ocean conditions or global climate change will negatively impact areas that were historically dependent on these fish, and change the food web structure

Characteristics of the cold-water belt formed off Soya Warm Current

Science.gov (United States)

Ishizu, Miho; Kitade, Yujiro; Matsuyama, Masaji

2008-12-01

We examined the data obtained by acoustic Doppler current profiler, conductivity-temperature-depth profiler, and expendable bathythermograph observations, which were collected in the summers of 2000, 2001, and 2002, to clarify the characteristics of the cold-water belt (CWB), i.e., lower-temperature water than the surrounding water extending from the southwest coast of Sakhalin along the offshore side of Soya Warm Current (SWC) and to confirm one of the formation mechanisms of the CWB as suggested by our previous study, i.e., the upwelling due to the convergence of bottom Ekman transport off the SWC region. The CWB was observed at about 30 km off the coast, having a thickness of 14 m and a minimum temperature of 12°C at the sea surface. The CWB does not have the specific water mass, but is constituted of three representative water types off the northeast coast of Hokkaido in summer, i.e., SWC water, Fresh Surface Okhotsk Sea Water, and Okhotsk Sea Intermediate Water. In a comparison of the horizontal distributions of current and temperature, the CWB region is found to be advected to the southeast at an average of 40 ± 29% of the maximum current velocity of the SWC. The pumping speed due to the convergence of the bottom Ekman transport is estimated as (1.5-3.0) × 10-4 m s-1. We examined the mixing ratio of the CWB, and the results implied that the water mass of the CWB is advected southeastward and mixes with a water mass upwelling in a different region off SWC.