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Fish are acutely affected by the increasing number of chemicals in the ambient water, including endocrine disruptors (EDC’s). EDCs include heavy metals such as cadmium and mercury, the polycyclic hydrocarbon benzo(a)pyrene, polychlorinated biphenyls, phthalates, carbamate and organophosphate pesticides, organochlorines, and bisphenol A. Nevertheless, certain groups of EDCs do manifest a comparatively greater effect on specific endocrine glands. The endocrine dysfunctions induced by explicitly acting EDCs include changes in fertility and in the ratio of male and female fish, classified as xenoestrogens or xenoandrogens. These EDCs result in a high prevalence of intersex condition including sex reversal. Feminization of male and masculinization of female fish pose a serious threat for fish populations, causing reduction or even breakdown of the reproductive performance of fish and of the yield of fisheries. It is now widely accepted that fish provide reliable biomarkers of early effects of EDC’s which data can be used as a warning signal for the ecosystem in general and a lever to diminish or prevent further release of effluents and discharges from anthropogenic activities.

This study outfitted wild-caught white seabass (Atractoscion nobilis) with electronic data storage tags (DSTs) to evaluate subsequent movements of adult fish captured along Baja California, Mexico (BC). Cefas G5 DSTs were surgically implanted into 89 wild-caught white seabass ranging in size from 66 to 152 cm TL between La Salina (32.11°N/116.90°W) and San Quintin (30.25°N/115.83°W), BC. Twenty-four tagged individuals (27%) were recaptured between April, 2010 and May, 2017, following a mean time at liberty of 608 days (range = 18–1424 days) and a mean displacement of approximately 125 km (± 173 km; range = 3–720 km) between the point of release and recapture. Tagged white seabass were recaptured between Santa Rosalillita, BC (28.66° N/114.27°W) and Monterey Bay, California (36.65°N/121.86°W), with four individuals reported above the U.S-Mexico border. Collectively, 8547 days of archived data revealed that white seabass spent 95% of the time at depths

Gradual transfer experiments were conducted to see whether Japanese dace Tribolodon hakonensis (freshwater species) and Japanese black porgy Acanthopagrus schlegelii (marine species) could acclimate to high and low temperatures in natal and non-natal osmotic environments. Two groups of each species, one acclimated to their natal osmotic environment and the other to a non-natal osmotic environment, were exposed to gradual temperature changes. Under high temperature conditions, the plasma osmolality (Posm) of both species approached the osmolality of ambient water, and high mortality was observed in the non-natal osmotic environments but not in the natal osmotic environments. In contrast, there was no clear evidence that the osmoregulatory capacity of either species had declined under low temperature conditions in the natal and non-natal osmotic environments. Limited adaptation of these fishes to non-natal osmotic environments at high temperature suggests that global warming may impair their entry to non-natal habitats.

Heavy metals are widely concerning because of their toxicity, persistence, non-degradation and bioaccumulation ability. Human health ambient water quality criteria (AWQC) are specific levels of chemicals that can occur in water without harming human health. At present, most countries do not consider the effects of aquatic vegetables in deriving human health AWQC. Therefore, the intake of aquatic vegetables (Brasenia schreberi) was added to the derivation of human health AWQC and a health risk assessment for 13 heavy metals in Taihu Lake. The human health AWQC (consumption of water, fish and aquatic vegetables) values of 13 heavy metals ranged from 0.04 (Cd) to 710.87 µg/L (Sn), and the intake of B. schreberi had a very significant effect on the human health AWQC for Cu, with a more than 62-fold difference. The hazard quotients of As (2.8), Cd (1.6), Cr (1.4) and Cu (4.86) were higher than the safe level (HQ = 1), indicating that As, Cd, Cr and Cu in Taihu Lake posed a significant health risk. Sensitivity analysis showed that the contribution rate of B. schreberi intake to the human health risk from Cu was 91.6%, and all results indicated that the risk of Cu in B. schreberi to human health should be of particular concern. This study adds the consideration of aquatic vegetable consumption to the traditional method of human health AWQC derivation and risk assessments for the first time, and this approach can promote the development of risk assessments and water quality criteria.

Plastic is able to sorb environmental pollutants from ambient water and might act as a vector for these pollutants to marine organisms. The potential toxicological effects of plastic-sorbed pollutants in marine organisms have not been thoroughly assessed. In this study, organic extracts from four types of plastic deployed for 9 or 12 months in San Diego Bay, California, were examined for their potential to activate the aryl hydrocarbon receptor (AhR) pathway by use of the H4IIE-luc assay. Polycyclic aromatic hydrocarbons (PAH), including the 16 priority PAHs, were quantified. The AhR-mediated potency in the deployed plastic samples, calculated as bio-TEQ values, ranged from 2.7 pg/g in polyethylene terephthalate (PET) to 277 pg/g in low-density polyethylene (LDPE). Concentrations of the sum of 24 PAHs in the deployed samples ranged from 4.6 to 1068 ng/g. By use of relative potency factors (REP), a potency balance between the biological effect (bio-TEQs) and the targeted PAHs (chem-TEQs) was calculated to 24-170%. The study reports, for the first time, in vitro AhR-mediated potencies for different deployed plastics, of which LDPE elicited the greatest concentration of bio-TEQs followed by polypropylene (PP), PET, and polyvinylchloride (PVC).

Movements undertaken by marine organisms occur for varying reasons and knowledge surrounding them is critically important for understanding population structures, ecology and for effective management and conservation of species. The objective of this study was to test a hypothesis that the cubozoan jellyfish Alatina alata spends a large part of its life at great depths by utilising the recently validated technique of statolith elemental chemistry. The approach was to ground-truth estimates of temperature based on a previous manipulative laboratory-based experiment, determine Sr:Ca and Ba:Ca ratios in the statoliths of A. alata at different life-history stages and use elemental chemistry as an environmental marker to estimate their life-time movements. High Sr:Ca values in the core and edge of the statoliths were found which corresponded with the time jellyfish were in shallow waters. Ambient water temperatures estimated for the end period of the jellyfish’s lives closely matched known sea surface temperatures in Hawaii, hence supporting a correlation between statolith Sr:Ca and temperature. For the middle section of the statoliths, strong evidence from both Sr:Ca and Ba:Ca ratios suggested that the jellyfish reached depths of at least 200–400 m. Ba:Sr maxima further supported this as Ba concentrations are usually higher below the thermocline. Individual Sr:Ca tracks also suggested that individuals moved over a depth range of tens to hundreds of meters through undertaking regular vertical movements. This study demonstrates that the use of elemental chemistry within cubozoan statoliths has the potential to determine vertical and horizontal movements where temperature gradients are strong.

This study simulated the operation of discharge ducts in desalination plants to examine the effects exerted by the convergence and longitudinal slope of discharge channels on the spreading of horizontally flowing convergent and inclined rectangular surface jets over the bed of deep and stagnant ambient water. To this end, a 3.2 × 0.6 × 0.9 m3 flume was used, and rectangular channels with convergence angles of 12.5°, 25°, 45°, and 90° were designed. The used jet fluid was a salt water solution with a concentration of 45 g/L. The channels were activated to discharge jet fluid tangentially at a constant depth of 0.7 m into the ambient water surface. After the experiments, data analysis was carried out through image routing. Results indicated that flow distribution over the bed was circular and elliptical. The relationship between radial distance from the impingement point to the outer boundary of flow and time was determined to a power of 0.45 under discharge conditions without a longitudinal slope and to powers of 0.57 and 0.42 under discharge conditions characterized by an inclined slope. Finally, the spreading coefficients of the jets at average, major, and minor radial distances are 4, 2, and 4.5, respectively.

Much has been revealed about fish migration, including diadromous behaviour, through the use of otolith chemistry. Manipulative experiments assist with unravelling information on otolith chemical composition and incorporation thereby answering specific questions on diadromous movements. In this study, a laboratory-based experiment was used to determine the relative and interactive effects of salinity and water temperature on the composition of three key elements (Sr, Ba and Mg) within the otolith of a catadromous fish, Percalates novemaculeata, endemic to south-eastern Australia. Otolith incorporation of Sr and Ba was positively related to ambient water concentration, whereas Mg incorporation was not. Sr and Ba increased and decreased significantly across salinity gradients, respectively, with minor positive effects of temperature also being detected. Salinity and temperature interacted to significantly affect the elemental concentration ratios for Ba: Ca in otoliths. Discrimination between fresh water and marine environments shows promise for interpreting P. novemaculeata residency based on these elements alone. However, deciphering finer scale movements within estuarine environments may be difficult. Our data highlights the importance of multifactorial validation experiments and suggests complementary use of multiple approaches for unravelling species-specific patterns of fish movement and habitat use.

Toxicity values for nickel on marine diatoms and copepods were derived based on bioassay tests. The 96 h IC50 of nickel on diatoms, Odontella mobiliensis and Coscinodiscus centralis were 0.31 ± 0.01 and 0.62 ± 0.02 mg/L and LC50 values on copepods, Oithona similis and Acartia danae were 2.78 ± 0.14 and 2.34 ± 0.32 mg/L, respectively. The species mean chronic values of nickel were 0.016, 0.17, 0.57 and 0.42 mg/L for O. mobiliensis, C. centralis, O. similis and A. danae, respectively. A hazardous concentration was derived and evaluated using the species sensitivity distribution (SSD) method. SSD indicated that 13 µg Ni/L is the maximum allowable concentration for protection of 95% plankton species in coastal and marine ecosystem of India. Diatoms are more sensitive to nickel than copepods by almost an order of magnitude. The toxicity values derived in the present study may be useful to calculate ambient water quality criteria/standard for nickel.

Although archival tags have been deployed in Thunnus since the early 1990s, few studies have placed such loggers on the small-size growth stage. In this study, Pacific bluefin tuna (PBT, Thunnus orientalis) 20–26.5 cm in fork length (FL) were fitted with archival tags and released off the southern coastal area of Japan from July to August in 2012, 2013, and 2014. Time-series data on swimming depth, ambient water temperature, and peritoneal cavity temperatures collected at 30-s intervals during 78–144 days were analyzed in 11 age-0 PBT. In August, the age-0 PBT spent 69.5 to 83.4% of their time within the mixed layer at mean temperatures between 27.6 and 28.3 °C, while previous studies reported that PBT with FL > 50 cm in the East China Sea are found most often in zones with temperatures between 14 and 19 °C. The thermal difference between the peritoneal cavity and ambient temperature was less than 1 °C for age-0 PBT in August, indicating that they were not in danger of overheating. The mean daytime swimming depths of age-0 PBT were significantly and positively correlated with the depth of the thermocline, especially from August to October. By focusing their swimming depths around the thermocline, the age-0 PBT potentially maximize the probability of encountering prey. There was a significant correlation between the mean nighttime depth and lunar illumination. The change in vertical distribution with the lunar cycle during nighttime is likely a form of predator avoidance.

Management of produced water (PW) is a challenge for mature fields like those of Sonda de Campeche in the southern Gulf of Mexico and for the future development of deep water fields. Past studies suggest that PW effects are local; however, the risk of widespread, long-term impact on the population and ecosystem is considered low, but not verified from the published literature. The study describes monitoring events done in years 2003 and 2013, considering physicochemical characteristics, organic and inorganic environmental measurements as well as comparing the prognostic results of an environmental and health risk assessment. The study examined ambient water samples and sediments for Al, Ba, Ni, Cd, Pb, Zn, V, Cr, Cu, Fe, and As, and also polycyclic aromatics compounds included in tissues of collected fish near the discharge area and a reference coastal site assumed to be unaffected. From a regional perspective, the ecological and human risk data suggest that the effects of the present discharge are not confined locally, but increased with time and space.

Pressure swing adsorption of nitrogen onto granular activated carbon in the single-bed adsorber–desorber chamber has been studied at six different pressures 6–18 kgf/cm2 to evaluate their performance as an alternative refrigeration technique. Refrigerating effect showed a linear rise with an increase in the operating pressure. However, the heat of adsorption and COP exhibited initial rise with the increasing operating pressure but decreased later after reaching a maximum value. The COP initially increases with operating pressures however, with the further rise of operating pressure it steadily decreased. The highest average refrigeration, maximum heat of adsorption and optimum coefficient of performance was evaluated to be 415.38 W at 18 kgf/cm2, 92756.35 J at 15 kgf/cm2 and 1.32 at 12 kgf/cm2, respectively. The system successfully produced chilled water at 1.7 °C from ambient water at 28.2 °C.

Leucocytherella sinensis, a ubiquitous and the most abundant ostracod endemic to the Tibetan Plateau, can account for >98% of the ostracod association. These low-diversity associations are hard to interpret using community palaeoecology alone, but environmentally driven phenotypic variation may provide clues to palaeoenvironmental factors. L. sinensis displays several morphological forms, characterised by different tubercle formation on their valves. These morphological forms were described as diverse species. We present a taxonomical revision and a first description of the soft parts of L. sinensis. We also redescribe the genus and confirm its assignment to the subfamily Limnocytherinae Klie, 1938. Analysis of L. sinensis associations from surface sediments of 12 Tibetan lakes shows a connection between tubercle formation and specific conductivity (SC) of the ambient water with lower tubercle number at higher salinity. Tubercles are less common in low SC populations and highest within the beta-oligohaline range. However, high Ca2+ concentrations suggest a combined effect of salinity and Ca2+ ion concentration on tubercle formation. The phenomenon of tubercle formation can be used to trace salinity changes recorded by fossil L. sinensis valves from Tibetan Holocene lake sediments.

An experiment was conducted to delineate the effect of heat shock and chlorine on the biochemical responses of Labeo rohita spawns for evaluating acquired thermal tolerance. Spawns were equally distributed in three different groups i.e., group 1 heat shock (37 °C) without chlorine, group 2 heat shock (37 °C) in chlorinated water and group 3 control in ambient water (28 °C). Following 1-h stress, the animal was transferred to ambient water conditions to study the recovery from stress at different sampling hours i.e., 0, 2, 4, 8, 14, 24 and 48 h. Stress parameters viz., glucose, lactate dehydrogenase, malate dehydrogenase and adenosine triphosphatase were measured for both the experimental groups and compared with the control. At the end of 48 h, the recovering spawns in the respective experimental groups were subjected to temperature higher than 37 °C in order to check for thermal tolerance and induction of cross protection. Their survivability rates were checked after exposure to 38, 39, 40, 41 and 42 °C. The result indicated that the spawns in group 1 recovered within 24 h wherein heat shock alone imparted higher thermal tolerance in them leading to 100 % survival at 40 °C; however the fishes in group 2 did not recover even after 48 h and demonstrated only 30 % survival at 40 °C. In both experimental groups, none of the fish survived the exposure to 42 °C. The results indicate that the combined effect of heat shock and chlorine has more pronounced effect on L. rohita spawns and fails to develop acquired thermal tolerance.

Tribological mechanism of the diatom frustule with multi-layers of pores is studied with the liquid-solid interaction (FSI) method. Based on the reconstructed representative Coscinodiscus sp. frustule with two-layer porous structure, the tribological performances for the diatom frustule at its different pore diameter ratios, pore depth ratios, and velocities are solved through governing equations involved with FSI method. The numerical result shows that the existence of the two-layer porous structure of the diatom helps to reduce the friction between it and ambient water, and to increase its ability to resist the ambient water pressure. The two-layer porous structure effectively improve the tribological performances for the diatom frustule due to the change in the frustule velocity.

With ocean warming predicted globally, one of the mechanisms driving distributional shifts and changes in the abundance of resident fishes is reproductive output. The relationship between sea surface temperature and the reproductive activity of a eurythermic, resident coastal species, blacktail seabream Diplodus sargus capensis, was examined in the “ocean warming” hotspot of the northern Benguela. Reproductive activity was found to be restricted to periods when the water temperature dropped below 20 °C. A metadata analysis conducted on the D. sargus sub-species complex similarly showed that reproductive activity was restricted to temperatures between 15 and 20 °C, regardless of the range in ambient water temperature. Based on these findings and using satellite derived SST information, we examined D. s. capensis’s total and seasonal “reproductive scope” that is defined as either the area suitable for spawning each year or the duration of its potential spawning season at a fixed geographical locality, respectively. Trends were examined over the last three decades. Reproductive scope by area was found to be shrinking at a rate of 7 % per decade in southern Angola and expanding at a rate of 6 % per decade in northern Namibia. Reproductive scope by season decreased by 1.05 months per decade in Namibe, southern Angola and increased by 0.76 months per decade in Hentiesbaai, northern Namibia. Changes in reproductive scope may be a driving mechanism of distributional shifts in resident fishes, although the rate of the shifts is likely to be slow. More importantly, changes in reproductive scope will not be uniform throughout fish distributions and will most likely result in heterogeneous variations in fish abundance.

The introduction and subsequent spread of lionfish into the Atlantic Ocean and Caribbean Sea has become a worldwide conservation issue. These highly successful invaders may also be capable of introducing non-native microorganisms to the invaded regions. This study compared the bacterial communities associated with lionfish external tissue to those of native Bahamian fishes and ambient water. Terminal restriction fragment length polymorphism analyses demonstrated that lionfish bacterial communities were significantly different than those associated with three native Bahamian fishes. Additionally, all fishes harbored distinct bacterial communities from the ambient bacterioplankton. Analysis of bacterial clone libraries from invasive lionfish and native squirrelfish indicated that lionfish communities were more diverse than those associated with squirrelfish, yet did not contain known fish pathogens. Using microscopy and molecular genetic approaches, lionfish eggs were examined for the presence of bacteria to evaluate the capacity for vertical transmission. Eggs removed from the ovaries of gravid females were free of bacteria, suggesting that lionfish likely acquire bacteria from the environment. This study was the first examination of bacterial communities associated with the invasive lionfish and indicated that they support different communities of environmentally derived bacteria than Caribbean reef fishes.

The larvae of catfish, Clarias batrachus (av. wt. 15 ± 2 mg) were exposed to five concentrations of thyroxine (T4) with three feeding regimes. Five media 1.3 mcg L−1 (T-1), 2.2 mcg L−1 (T-2), 3.6 mcg L−1 (T-3), 6.0 mcg L−1 (T-4), 10.0 mcg L−1 (T-5) of T4 and control with three feeding regimes 1 day (once a day), 2 days (twice a day) and 3 days (thrice a day) were maintained in triplicate set in 54, troughs containing 2-L water. The larvae reared in media (T1, T2, T-3, T-4 & T-5) with feeding regimes 1 day, 2 days & 3 days showed 100 % survival which was significantly high (p

We determined the δD values of the total fatty acids of Japanese rice to test the hypothesis that there is a wide variation in the hydrogen isotopic composition (δD) of the total fatty acids of Japanese rice sourced from different growth areas in Japan and to distinguish the minor differences among these growth areas. The δD values showed a wide variation ranging from -216‰ (Hokkaido) to -183‰ (Okinawa), indicating a good correlation with the corresponding variations for ambient water (r = 0.63) and mean temperature (r = 0.84). These results suggest that the δD values for the total fatty acids can be representative of the growth environments in Japan.

Exotic animals can cause genetic contamination of indigenous species if they escape and reproduce in wild populations. The loach Misgurnus anguillicaudatus and species related to it have been imported into Japan for commercial use. We collected live loach specimens from the central wholesale market in Tokyo. For the 451 specimens collected, ploidy status was examined by DNA content flow cytometry, and polyploid loaches with triploid, tetraploid, and other higher ploidy ranges were detected. Hypertriploid and hypertetraploid individuals were easily detected by flow cytometry using standard eudiploid, eutriploid, and eutetraploid controls, and the reproductive capacities of these hyperpolyploid males were then examined. Sperm of hypertriploid males did not exhibit active progressive motility, and major populations of spermatozoa or spermatozoon-like cells were detected in the triploid and hexaploid ranges. Motile haploid spermatozoa were very rare in sperm from hypertriploid males. Therefore, hypertriploid males were sterile, whereas hypertetraploid males produced fertile hyperdiploid spermatozoa with active progressive motility after contact with ambient water. Viable progeny occurred in crosses between normal wild-type diploid females and hypertetraploid males, but androgenotes induced by the fertilization of UV-irradiated eggs with the sperm of hypertetraploid males were inviable hyperdiploids. Cytogenetic analyses of those androgenotes indicated that hypertetraploid males should produce hyperdiploid spermatozoa with 2n = 54 (i.e., four supernumerary microchromosomes).

We synthesized ZnO nanoparticles by laser ablation of a Zn target in water at pressures up to 30 MPa. We observed the enhancement of the crystallinity of synthesized ZnO nanoparticles when high pressure was applied to ambient water. In addition, we found that ZnO nanoparticles with smaller sizes were synthesized by pressurizing ambient water. Considering our previous understanding on the effect of high pressure applied to ambient liquid, the controls of the structure and the size of nanoparticles were considered to be obtained via the controls of the dynamics of laser ablation plasma and ablation-induced cavitation bubble.

Sr isotopic compositions of ayu otolith and water collected from Japanese rivers were measured to validate the relationship between otolith and ambient water for this species. Micromilling and rostrum-cut methods employed for otolith sampling were compared and yielded almost indistinguishable otolith Sr isotopic composition data. A good correlation observed between data on otolith and those on ambient water (river water and sea water) confirms the usefulness of Sr isotopic composition for elucidating migratory behavior of ayu, as already verified in other species.

Surface discharges of negatively buoyant jets into moving ambient water create a range of complex flow patterns. These complexities arise through the interplay between the discharge’s initial fluxes and the motion of the ambient current. In this study a series of laboratory experiments were conducted for negatively buoyant surface discharges into crossflow to investigate flow patterns under different discharge and ambient conditions. The results compared with simulations of the CORMIX model, an expert system for ocean outfall design. In CORMIX, the simulation module DHYDRO for dense discharges has been used. Finally the flow different patterns were arranged in a dimensionless diagram to propose a modified flow classification system with new criteria.

Water quality criteria (WQC) are threshold limits for pollutants or other hazard factors in the ambient water environment, which are based on scientific experiments and extrapolations. Until now, there is limited information available regarding the study of water quality criteria in China. It is imperative to launch national-level systematic WQC studies that focus on the regional characteristics of China and provide scientific support for the enactment or revision of water quality standards and environmental management. This article reviews the concept of WQC and discusses the methodology and global progress of WQC research. The article also summarizes the key scientific issues in WQC research, including species sensitivity distribution, toxicological endpoint selection, and models selection. Furthermore, we can adopt the derivation method used in the USA and divide WQC into acute and chronic criteria. Finally, considering the current status of WQC research in China, we point out important directions for future national studies, including the selection of native species and the comprehensive use of models.

The decrease in resting core temperature (T (co)) and its relation to the reduced physiological strain during heat acclimation was analysed with rectal temperature data measured in three groups of eight semi-nude persons (6 males, 2 females) who were acclimated for 15 consecutive days to dry, humid and radiant heat, respectively, with equivalent WBGT (33.5 degrees C), by performing 2-h treadmill work. A fourth group followed the same protocol for 12 days in a neutral climate. After acclimation, both resting T (co), prior to heat exposure, and final T (co), measured at the end of work, were significantly reduced. The reduction in final T (co) increased with decreasing ambient water vapour pressure and was higher for the data pooled over the heat conditions (0.46 +/- 0.31 degrees C) than in the neutral climate (0.21 +/- 0.25 degrees C), whereas resting T (co) declined similarly in the heat (0.20 +/- 0.25 degrees C) and the neutral environment (0.17 +/- 0.23 degrees C). The lowering of resting and final T (co) after heat acclimation showed a significant correlation (r = 0.67) and regression analysis showed that 37% of the average reduction in final T (co) was attributable to the lowering of resting T (co). The same analysis was applied after extending the database by short-term series of clothed persons (17 females, 16 males) acclimated at 29.5 and 31.5 degrees C WBGT for 5 days. A significant correlation was found between the lowering of resting and final T (co) (r = 0.57) that did not depend on climatic conditions and gender, although the reduction in resting T (co) was significantly smaller for females (0.06 +/- 0.22 degrees C) than for males (0.21 +/- 0.23 degrees C). It is concluded that the lowering of resting core temperature contributes to the reduced physiological strain during heat acclimation. Similar effects under neutral conditions point to the exercise stimulus as a probable explanation.

When microscopic organisms swim in their natural habitats, they are simultaneously transported by ambient currents, waves, and turbulence. Therefore, to understand how swimming affects the movement of very small creatures through the environment, we need to study their behavior in realistic water flow conditions. The purpose of the work described here was to develop a series of integrated field and laboratory measurements at a variety of scales that enable us to record high-resolution videos of the behavior of microscopic organisms exposed to realistic spatio-temporal patterns of (1) water velocities and (2) distributions of chemical cues that affect their behavior. We have been developing these approaches while studying the swimming behavior in flowing water of the microscopic larvae of various bottom-dwelling marine animals. In shallow marine habitats, the oscillatory water motion associated with waves can make dramatic differences to water flow on the scales that affect trajectories of microscopic larvae.

More than 30 laboratories routinely monitor water along southern California's beaches for bacterial indicators of fecal contamination. Data from these efforts frequently are combined and compared even though three different methods (membrane filtration (MF), multiple tube fermentation (MTF), and chromogenic substrate (CS) methods) are used. To assess data comparability and quantify variability within method and across laboratories, 26 laboratories participated in an intercalibration exercise. Each laboratory processed three replicates from eight ambient water samples employing the method or methods they routinely use for water quality monitoring. Verification analyses also were conducted on a subset of wells from the CS analysis to confirm or exclude the presence of the target organism. Enterococci results were generally comparable across methods. Confirmation revealed a 9% false positive rate and a 4% false negative rate in the CS method for enterococci, though these errors were small in the context of within- and among-laboratory variability. Fecal coliforms also were comparable across all methods, though CS underestimated the other methods by about 10%, probably because it measures only E. coli, rather than the larger fecal coliform group measured by MF and MTF. CS overestimated total coliforms relative to the other methods by several fold and was found to have a 40% false positive rate in verification. Across-laboratory variability was small relative to within- and among-method variability, but only after data entry errors were corrected. One fifth of the laboratories committed data entry errors that were much larger than any method-related errors. These errors are particularly significant because these data were submitted in a test situation where laboratories were aware they would be under increased scrutiny. Under normal circumstances, it is unlikely that these errors would have been detected and managers would have been obliged to issue beach water quality warnings.

As part of the NJ Toxics Reduction Workplan for NY-NJ Harbor, ambient water samples were collected at fifteen locations along the tidal portions of the Hackensack, Passaic, Raritan, Rahway and Elizabeth Rivers, and in Newark Bay, the Arthur Kill, and Kill van Kull. A Trace Organics Platform Sampler was used to collect a total of 75 suspended sediment phase samples between June 2000 and May 2002. These samples were analyzed for spatial and wet vs. dry weather trends in the 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs; modified USEPA Method 1613b). Mean total PCDD/F (tPCDD/F) concentrations at the sampling locations ranged between 3.8 and 41.5 ng/g. On average, OCDD accounted for almost 80% of the tPCDD/F concentrations; mean total [PCDD/F – OCDD] concentrations ranged between 0.84 and 5.20 ng/g at the sampling locations. Mean 2,3,7,8-TCDD concentrations ranged between 0.003 and 0.28 ng/g, with the highest concentrations (> 0.10 ng/g) along the tidal Passaic and lower Hackensack Rivers, and in upper Newark Bay. Mean tPCDD/F Toxic Equivalency Quotients (TEQ) ranged between 45 and 344 TEQ pg/g, with the highest levels found in the lower Passaic River. Toxicity was primarily driven by 2,3,7,8-TCDD concentrations in the Passaic and Hackensack Rivers, and in Newark Bay. Examples of congener distribution patterns at some of the sampling locations are also presented.

[Extract] During hydrodynamic disturbances such as cyclones and tsunamis, coral colonies are partially damaged whereby colony branches or segments are removed or dislodged from the substrate altogether (Woodley et al. 1981; Connell et al. 1997). Afterwards, those coral fragments that are unable to reattach to the substrate (Smith and Hughes 1999) are tumbled about by ambient water motion, resulting in extensive mortality regimes (Knowlton et al. 1981; Woodley et al. 1981). Despite the well-known role of hydrodynamic disturbance in structuring coral reef communities (Connell 1978), the fate of different colonial morphologies is unknown because researchers are unable to observe the reef during such destructive disturbances. To circumvent this obstacle, the present study uses a classical engineering approach to demonstrate the likely consequences for coral colonies when pushed to their mechanical limits by water motion. Contrary to common belief (Chamberlain 1978; Schuhmacher and Plewka 1981; Vosburgh 1982), this study finds that the overall mechanical integrity of coral colonies is highly unlikely to be determined by the strength of their carbonate skeletons, but rather by the highly variable and significantly weaker strength of the reef substrate to which they are attached. Furthermore, as the hydrodynamic force increases, the engineering model predicts that the pruning of colony branches is unlikely to occur before whole-colony dislodgement. It is suggested therefore that the superior strength of coral skeleton, which is found to be increasingly stronger in more mechanically vulnerable morphologies, may be an evolutionary solution for reducing the likelihood of branch removal by localized impacts of waterborne debris during hydrodynamic disturbances.

The problem on the thermal interaction between a hot thermal particle and ambient water is treated. The stability of a growing vapor film to small perturbations of its spherical shape is investigated.

Surface water quality monitoring is one of the responsibilities of a number of provincial and federal environmental departments in Canada. In Saskatchewan, the Ministry of Environment is responsible for the province water quality monitoring network. The sampling effort was initiated 40 years ago and has been ongoing since, with varying degrees of spatial and temporal coverage. The main objective of the Saskatchewan monitoring network is the assessment of ambient water quality status. In addition, one of the main uses of the generated water quality data is the calculation of a Water Quality Index. The adequacy of the monitoring network to perform these tasks needs to be validated. The objective of this study is to provide a statistical assessment of two of the monitoring network main aspects, the water quality variables and their sampling frequency. A new rationalization approach is applied for the assessment and reselection of water quality variables. The proposed approach provides, in a systematic way, the optimal combinations of variables to continue measuring, variables that may be redundant and could be considered for discontinuance, and variables that may need to be added to the list of variables being measured. The confidence interval around the mean is used as the main criterion for the sampling frequency assessment. A design chart is provided for the sampling frequency assessment, which is easy to use, and provides an initial assessment of the number of samples required to provide a mean value with a predefined error percentage.

We studied the effects of acidification on female sexual behavior in brown trout (Salmo trutta) and compared the results with those in hime (land-locked sockeye) salmon (Oncorhynchus nerka) (Kitamura and Ikuta, 2000). The results were similar to those of sockeye salmon. Spawning brown trout were extremely sensitive to the acidity of ambient water, and nest-digging behavior was severely inhibited (p

The developmental processes of larval and juvenile ayu.Plecoglossus altivelis, in the estuarine and freshwater sections of the Shimanto River were compared among cohorts hatched in November, December and January. Formation of fins and ossification of the centra, which were completed by about 35 mm BL, hardly differed among the three cohorts. In specimens over 35 mm BL, body depth and head length were smaller in the November cohort than in the other cohorts, with pigmentation in the earlierhatched cohort being completed at a grater BL. The November cohort also remained at the “whitebait” stage until reaching a larger size (about 45 mm BL), before transforming to juveniles and commencing upstream migration. In contrast, the January cohort transformed to juveniles and started upstream migration at a smaller size (under 40 mm BL). The difference in transformation size among the cohorts is probably caused by ambient water temperatures existing at the beginning of upstream migration of each.

/ The Intergovernmental Task Force on Monitoring has suggested studies on ambient (in-stream) and compliance (wastewater) data to determine if monitoring can be reduced locally or nationally. The similarity in temporal trends between retrospective ambient and compliance water-quality data collected from Pool 2 of the Mississippi River, USA, was determined for 1985-1995. Constituents studied included the following trace elements: arsenic (As), cadmium (Cd), chromium (Cr), hexavalent chromium (Cr(6+)), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), selenium (Se), zinc (Zn), and polychlorinated biphenyls (PCBs). Water-column, bed-sediment, and fish-tissue (fillets) data collected by five government agencies comprised the ambient data set; effluent data from five registered facilities comprised the compliance data set. The nonparametric Mann-Kendall trend test indicated that 33% of temporal trends in all data were statistically significant (P0.05). Possible reasons for this were low sample sizes, and a high percentage of samples below the analytical detection limit. Trends in compliance data were more distinct; most trace elements decreased significantly, probably due to improvements in wastewater treatment. Seven trace elements (Cr, Cd, Cu, Pb, Hg, Ni, and Zn) had statistically significant decreases in wastewater and portions of either or both ambient water and bed sediment. No trends were found in fish tissue. Inconsistency in trends between ambient and compliance data were often found for individual constituents, making overall similarity between the data sets difficult to determine. Logistical differences in monitoring programs, such as varying field and laboratory methods among agencies, made it difficult to assess ambient temporal trends.KEY WORDS: Mann-Kendall trend test; Ambient data; Compliance data; Trace elements; PCBs, Mississippi Riverhttp://link.springer-ny.com/link/service/journals/00267/bibs/24n4p497.html/HEA

We examined the relationship between body temperature (Tb) of free flying pigeons and ambient water vapor pressure and temperature. Core or near core Tb of pigeons were measured using thermistors inserted into the cloaca and connected to small transmitters mounted on the tail feathers of free flying tippler pigeons (Columba livia). Wet and dry bulb temperatures were measured using modified transmitters mounted onto free-flying pigeons. These allowed calculation of relative humidity and hence water vapor pressure at flight altitudes. Mean Tb during flight was 42.0 ± 1.3 °C (n = 16). Paired comparisons of a subset of this data indicated that average in-flight Tb increased significantly by 1.2 ± 0.7 °C (n = 7) over that of birds at rest (t = −4.22, P < 0.05, n = 7) within the first 15 min of takeoff. In addition, there was a small but significant increase in Tb with increasing ambient air (Ta) when individuals on replicate flights (n = 35) were considered. Inclusion of water vapor pressure into the regression model did not improve the correlation between body temperature and ambient conditions. Flight Tb also increased a small (0.5 °C) but significant amount (t = 2.827, P < 0.05, n = 8) from the beginning to the end of a flight. The small response of Tb to changing flight conditions presumably reflects the efficiency of convection as a heat loss mechanism during sustained regular flight. The increase in Tb on landing that occurred in some birds was a probable consequence of a sudden reduction in convective heat loss.

Effects of temperature on oxygen consumption rate (OCR) and ammonia—N excretion rate of scallopChlamys farreri (1.7–6.2 cm in shell height) were studied in laboratory from Dec. 30,1996 to Jan. 28,1997. Under the controlled conditions of ambient water temperature 10–31°C and salinity 32, the concentrations of dissolved oxygen and ammonia—N were determined by the Winkle method and the hypobromite method, respectively. Results showed that the OCR ranged from 1.20 mg/g (DW) · h to 5.76 mg/g (DW) · h. The OCR increased with temperature from 10°C to 23°C, but at 28°C the OCR of mature individuals decreased, and that of different size scallops reduced at 31°C. The ammonia—N excretion rate ranged from 113.03 μg NH4-N/g (DW) · h to 486.63 μg NH4-N/g (DW) · h, and increased with temperature from 10°C to 31°C.

Stomach temperatures of three white sharks, Carcharodoncarcharias, (one reported previously and two new individuals) were intermittently recorded by acoustic telemetry at the South Farallon Islands, central California. Temperature profiles of the water column were obtained concurrently. Stomach temperatures were elevated over ambient water temperatures by as much as 14.3 °C. Stomach temperatures varied within a narrow range while ambient water temperature fluctuated over a much larger range, showing that this species regulates its body temperature. These data, in combination with previous work on the physiology and anatomy of white sharks, indicate that the white shark is endothermic. It appears that the heat retention system in lamnid sharks has allowed them to inhabit cold water and remain active predators of swift and agile prey.

Average and 75 % biochemical oxygen demand (BOD) in the Yamato-gawa River, Japan, in 1963 were smaller than the criteria determined in 1970 (5 mg l−1); however, they were deteriorated up to 22–32 mg l−1 in 1970. The deterioration was caused by the population increase and economic and urban development. The national-level regulations on ambient water quality and pollutant discharge have been established in 1970. Municipal wastewater is the major contributor in pollutant discharges in the river basin. Estimated BOD discharge (PD(BOD)) in the river basin reduced to the level of 1963 in 2000; however, average and 75 % BOD were more than the criteria. Analysis on the relationship between BOD and PD(BOD) resulted in the five phases in 1963–2009. The equilibrium conditions changed from phase I to II because of the perturbation caused by the excess BOD discharge, self-correcting mechanisms were found in phase III, and equilibrium conditions changed from phase III to IV and V. The comparison of estimated BOD based on pollutant generation (PG) without measures and monitored BOD represented the following situations in 47 years: (1) It took several years before the effects of centralised WWTPs were observed, (2) PD(BOD) was less than 35 t-BOD day−1 for the linear relationship of PD(BOD) and BOD, and (3) combined effects of wastewater treatment, river water purification facilities and soft measures were estimated to be about 10 mg-BOD l−1 in 2010.

Body temperatures, ambient water temperatures, light intensities and vertical positions (depth) of eight loggerhead turtles, Caretta caretta, were monitored by small recorders during internesting periods from 1991 through 1993 off Wakayama Prefecture, Japan. Body temperatures of eight loggerhead turtles were higher than ambient water temperatures through-out their internesting periods. Light intensities were compared with body temperatures and no evidence was obtained to suggest that the raised body temperatures were caused by the direct influence of solar radiation. Body temperatures were kept higher than water temperatures in cloudy weather or even at night. Mean thermal differences between body and water temperatures were significantly different among individuals, and larger turtles had a greater mean thermal difference. Elevations in body temperatures of adult loggerhead turtles can reasonably be assumed to result from the accumulation of metabolically produced heat. Surfacing times (spent at depths shallower than 2 m) of seven turtles were only 10.3 to 38.9% of their internesting periods, with the exception of one turtle who spent 66.3% of her time at the surface. Loggerhead turtles did not seem to bask positively at the sea surface to absorb radiative heat.

According to present understanding, persistent superlipophilic chemicals — such as octachlorodibenzo-p-dioxin, octachlorodibenzofuran, Mirex etc — with log Kow > 6 and cross sections > 9.5 A, bioconcentrate in aquatic organisms only little from ambient water. The most convincing argument against it is that in bioconcentration experiments with superlipophilic chemicals amounts applied exceeded water solubility by several orders of magnitude. This paper describes various methods for determining bioconcentration factors (BCF) of superlipophilic compounds. As exemplified with octachlorodibenzo-p-dioxin, BCF values evaluated by these methods match well with those calculated by QSARs for fish and mussels based on log Kow and water solubility. As expected, these BCF values exceed previous values by several orders of magnitude. For BCF evaluation of superlipophilic chemicals in aquatic organisms we recommend: (i) flow-through systems, kinetic method (OECD guideline No. 305 E) (ii) ambient concentrations < water solubility (iii) during the uptake and especially during the elimination phase no toxic effects of the test organisms should occur.

Instruments were attached to loggerhead turtles, Caretta caretta, at Kamoda Point, Japan in 1989 and on the Senri-coast, Japan in 1991. We simultaneously obtained stomach temperatures, ambient water temperatures and diving depths from four free-ranging loggerhead turtles during the internesting periods, using small recorders. These data were analyzed to understand how body temperature was maintained. Ambient water temperatures changed coincidentally when turtles moved up or down, but a stable stomach temperatures was maintained despite water temperature fluctuations of ca. 20 to 90 min in duration. Loggerhead turtles also experienced water temperature fluctuations longer than 24 h. Stomach temperatures responded to those water temperature changes with a time lag of several hours (160, 170, 230 and 240 min). Stomach temperatures were higher than ambient water temperatures throughout the experimental periods. The median values of the thermal difference between stomach and water temperatures were 1.1, 1.3, 1.5 and 1.7°C. The higher stomach temperatures are thought to be caused by metabolic heat production.

A study on natural convection from a horizontal ice surface melting in pure water was conducted experimentally for the ambient water temperature from 2▿C to 10°C. Natural convection flow around upward-or downward-facing horizontal ice plate was divided into three regions according to the temperature variation of ambient water. The flow patterns of three regions were no flow, two-dimensional steady laminar flow and unsteady flow. Mean Nusselt number for the upward-facing surface had its maximum value at about 3°C of ambient water temperature. However, in the case of the downward-facing surface it increased as the ambient water temperature increased.

Almost half (354) of all fish kills (805) in South Carolina, USA, between 1978 and 1988 occurred in the coastal zone. These kills were analyzed for causative, spatial, and temporal associations as a distinct data set and as one integrated with ambient water quality monitoring data. Estuarine kills as a result of natural causes accounted for 42.8% followed by man-induced (35.1%) and undetermined causes (22.1%).

The apparatus allows the sampling of both algal and animal components of the epiphyton. It consists of a perspex tube, 100 cm long with an internal diameter of 4 cm, and of an epiphytic sieve. The latter is made of two 2.5 cm cross-sections of perspex tubing with a piece of circular mesh glued between them. While sampling, a randomly chosen shoot is isolated from the ambient water by means of the tube, cut at the bottom sediment and removed together with epiphyton. The water, taken together with the shoot is then removed using the epiphytic sieve, joined with the tube under the water surface. The detached organisms, associated with the stem and those scraped from the stem with a stiff brush afterwards, concentrate on the mesh.

An ambient loop USP purified water system has been designed and implemented using carbon and ion exchange resin beds, ultraviolet light systems and polishing filters to produce water consistently meeting or exceeding all USP XXIII quality specifications for purified water. The circulation system is constructed of PVDF plastic piping material installed in a continuous fully-drainable loop. The system was sized for a pilot scale fermentation/harvest process at the 1000 l cultivation scale. This system passed all installation and operational qualification testing as well as sixty days of continuous performance qualification testing before entering into an ongoing monitoring regimen. Excursions outside acceptable water quality parameters during this extensive monitoring regimen were minimal. Sanitization of the system, along with bed and filter changes at the time of sanitization, was conducted every 3 to 6 months to insure consistent water quality.

Illinois has been operating an ambient water quality network of almost 600 stations for several years. In 1977 changes in program emphasis toward intensive monitoring, the need for improved procedures and quality control in monitoring operations, and the desire to create a single data base of all Illinois State monitoring data, resulted in a redesign of the ambient monitoring program.

Inorganic mercury under high pH values was not as readily translocated from water into fish as under low pH conditions, even though abundant in high pH water. The translocation of mercury into fish is not dictated by analytical concentration of mercury (II) in water only. It is evident that pH of ambient water has great effect on translocation. It is important to note that this finding is closely in agreement with data obtained in the field (KONRAD 1971). While under alkaline conditions, more inorganic mercury is released into water (MATSUMURA et al. 1972), but the rate of pickup by fish is reduced. The cause of such a reduction might be related to those unreactive forms of mercury complexes formed under alkaline conditions. (auth)

Absorption of volatile fatty acids (propionate, acetate, butyrate, and formiate) from the ambient water by the lugwormarenicola marina was demonstrated using14C-labelled compounds and by gas-liquid chromatography. Uptake was investigated in the presence of antibiotics. The rate of uptake was highest with propionate (vmax 0,58 μmol g-1 w wt · h, Kt 0.75 μmol l-1). Butyrate, acetate, and formiate were absorbed at lower rates in that order. Absorption of propionate, butyrate, and acetate showed saturation kinetics. In the presence of butyrate and acetate, propionate absorption was inhibited (maximum inhibition 78%). These results indicate that a carrier is involved in the absorption of propionate. Following absorption, the volatile fatty acids were rapidly metabolized. The largest proportion of label was incorporated into amino acids, with the pattern of distribution of radioactivity being specific for each volatile fatty acid.

Lactic acid excreted by the fish,Tilapia mossambica subjected to exercise has been measured in ambient water. The method of Barker and Summerson has been modified suitably for estimating lactic acid in the fish medium: decarbonated tap water.T. mossambica excreted 25·7, 31·1 and 31·6 mg/kg/hr of lactate at 35 cm/sec of swimming speed and 47·0, 60·2 and 54·6 mg/kg/hr of lactate at 93 cm/sec of swimming speed at the end of 1 hr of exercise at 25, 30 and 35°C respectively.