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1

Acidification of Lower St. Lawrence Estuary Bottom Waters  

Microsoft Academic Search

Accumulation of metabolic CO2 can acidify marine waters above and beyond the ongoing acidification of the ocean by anthropogenic CO2. The impact of respiration on carbonate chemistry and pH is most acute in hypoxic and anoxic basins, where metabolic CO2 accumulates to high concentrations. The bottom waters of the Lower St. Lawrence Estuary (LSLE), where persistently severe hypoxia has developed

Alfonso Mucci; Michel Starr; Denis Gilbert; Bjorn Sundby

2011-01-01

2

Late-Quaternary morpho-sedimentology and submarine mass movements of the Betsiamites area, Lower St. Lawrence Estuary, Quebec, Canada  

E-print Network

-sedimentology multibeam bathymetry seismic reflection earthquakes St. Lawrence Estuary Betsiamites River A complex submarine geomorphology was revealed from multibeam bathymetry and seismic reflection surveys conducted between 2001 and 2007 in the Lower St. Lawrence Estuary offshore Betsiamites River, Quebec, Canada

Long, Bernard

3

Aerobic respiration and hypoxia in the Lower St. Lawrence Estuary: Stable isotope ratios of dissolved oxygen constrain oxygen sink partitioning  

E-print Network

Aerobic respiration and hypoxia in the Lower St. Lawrence Estuary: Stable isotope ratios of St. Lawrence to determine the relative importance of pelagic and benthic dissolved oxygen respiration, as would be expected from O-isotope fractionation associated with bacterial oxygen respiration

Long, Bernard

4

A multibiomarker approach on the Atlantic tomcod (Microgadus tomcod) in the St. Lawrence Estuary.  

PubMed

A multibiomarker approach was developed on juvenile Atlantic tomcod (Microgadus tomcod) to evaluate the pertinence of this approach for low-cost screening assessment of the environmental quality of various coastal sites within estuaries. Several biometric indices and biomarkers (ethoxyresorufin-O-deethylase (EROD) activity, metallothionein concentration, and immune responses) were investigated on immature and maturing tomcods (? 31 months) collected in four environmentally contrasted sites in the St. Lawrence Estuary (SLE). Simultaneous examination of various age classes provides the opportunity to detect short-term responses in sensitive young-of-the-year fish (e.g., EROD induction) and longer-time effects associated with chronic exposure and bioaccumulation (e.g., metallothionein induction). Principal component analysis was helpful to discriminate between responses possibly related to contaminant exposure (EROD, metallothionein) and responses that could be affected by upstream-downstream gradient (immune response, biometric indices). Measurement of a battery of biomarkers in young tomcods at several sites along the shore of the SLE is a low-cost screening investigation useful to identify hot spots requiring further investigation with chemical analysis and additional reference sites. PMID:23192300

Dupuy, Célie; Couillard, Catherine M; Laroche, Jean; Nellis, Pierre; Brousseau, Pauline; Fournier, Michel

2013-02-01

5

Molecular and spectroscopic analysis of non-hydrolyzable sedimentary organic matter from the St. Lawrence Estuary  

NASA Astrophysics Data System (ADS)

Sediments are the ultimate long-term sink for organic carbon (OC) on Earth, thus playing an important role in the global cycles of O2 and CO2. Estuaries and river deltas are major conduits for terrestrial organic matter (OM) into marine systems, where it is mixed with locally produced OM and is eventually deposited and buried in the sediment bed. About 45% of global OC burial occurs along these river deltas and estuaries (Hedges and Keil, 1995), therefore it is of interest to follow OM deposition and preservation in these terrestrial to marine transition zones. We chemically fractionated bulk OM from a series of sediments from the St. Lawrence Estuary and Gulf into distinct reactivity classes. We define three such OM fractions based on pioneering work by Hedges and Keil (1995) who classified OM based on chemical reactivities: labile (degradable at similar rate under oxic and anoxic conditions), non-hydrolyzable (degraded primarily under oxic conditions), and refractory (preserved on long time scales independently of redox conditions). Here we present data on the elemental (C and N), isotopic (?13C and ?15N) and spectroscopic (FTIR, HR-MAS 1H/13C NMR) characterization of the different fractions, focusing primarily on the non-hydrolyzable fraction because of its importance in the long-term burial of OC below the seafloor. We used mild oxidation methods (cupric oxide and ruthenium tetroxide oxidation) followed by chromatographic analysis of the oxidation products. Combining results from the bulk and molecular analytical techniques provides insights into the composition and cycling of non-hydrolyzable OM in transitional system, from which OM preservation can be better understood. Hedges, J. I., Keil, Richard G. (1995). "Sedimentary organic matter preservation: an assessment and speculative synthesis." Marine Chemistry 49(2-3): 81-115.

Ibrahim, M.; Simpson, A. J.; Gelinas, Y.

2011-12-01

6

Holocene paleomagnetic records from the St. Lawrence Estuary, eastern Canada: centennial to millennial-scale geomagnetic modulation of cosmogenic isotopes  

Microsoft Academic Search

Two long Holocene piston cores (MD99-2220 and MD99-2221) were raised from the St. Lawrence Estuary, eastern Canada because of the expanded Holocene sediment sequence this location provides. A u-channel-based paleomagnetic study, supported by an accelerator mass spectrometry (AMS) 14C chronology, rock-magnetic and sedimentological data, indicates that these sediments provide a paleomagnetic directional secular variation (PSV) and relative paleointensity (RPI) proxy

Guillaume St-Onge; Joseph S. Stoner; Claude Hillaire-Marcel

2003-01-01

7

Anammox, denitrification and fixed-nitrogen removal in sediments from the Lower St. Lawrence Estuary  

NASA Astrophysics Data System (ADS)

Incubations of intact sediment cores and sediment slurries reveal that anammox is an important sink for fixed nitrogen in sediments from the Lower St. Lawrence Estuary (LSLE), where it occurs at a rate of 5.5 ± 1.7 µmol N m-2 h-1. Canonical denitrification occurs at a rate of 11.3 ± 1.1 µmol N m-2 h-1, and anammox is thus responsible for up to 33% of the total N2 production. Both anammox and denitrification are mostly (> 95%) fueled by nitrate and nitrite produced in situ through benthic nitrification. Nitrification accounts for > 15% of the benthic oxygen demand and may, therefore, contribute significantly to the development and maintenance of hypoxic conditions in the LSLE. The rate of dissimilatory nitrate reduction to ammonium is three orders of magnitude lower than denitrification and anammox, and it is insignificant to N-cycling. NH4+ oxidation by sedimentary Fe(III) and Mn(III/IV) in slurry incubations with N isotope labels did not occur at measurable rates; moreover, we found no evidence for NH4+ oxidation by added Mn(III)-pyrophosphate.

Crowe, S. A.; Canfield, D. E.; Mucci, A.; Sundby, B.; Maranger, R.

2012-11-01

8

Anammox, denitrification and fixed-nitrogen removal in sediments of the Lower St. Lawrence Estuary  

NASA Astrophysics Data System (ADS)

Incubations of intact sediment cores and sediment slurries reveal that anammox is an important sink for fixed nitrogen in the Lower St. Lawrence Estuary (LSLE), where it occurs at a rate of 5.5 ± 1.7 ?mol N m-2 h-1 in the sediment. Anammox is responsible for up to 33% of the total N2 production, and both anammox and denitrification are mostly (>95%) fueled by nitrate and nitrite produced in situ through benthic nitrification. Nitrification accounts for >15% of the benthic oxygen demand and contributes significantly to the development and maintenance of hypoxic conditions in the LSLE. The rate of dissimilatory nitrate reduction to ammonium is three orders of magnitude lower than denitrification and anammox and is therefore insignificant to N-cycling. Tests for NH4+ oxidation by sedimentary Fe(III) and Mn(III/IV), using slurry incubations with N isotope labels, revealed that it does not occur at measurable rates, and we found no evidence for NH4+ oxidation by added Mn(III)-pyrophosphate.

Crowe, S. A.; Canfield, D. E.; Mucci, A.; Sundby, B.; Maranger, R.

2011-09-01

9

Seasonal variability of denitrification efficiency in northern salt marshes: an example from the St. Lawrence Estuary.  

PubMed

In coastal ecosystems, denitrification is a key process in removing excess dissolved nitrogen oxides and participating in the control of eutrophication process. Little is known about the role of salt marshes on nitrogen budgets in cold weather coastal areas. Although coastal salt marshes are important sites for organic matter degradation and nutrient regeneration, bacterial-mediated nitrogen cycling processes, such as denitrification, remain unknown in northern and sub-arctic regions, especially under winter conditions. Using labelled nitrogen (15N), denitrification rates were measured in an eastern Canadian salt marsh in August, October and December 2005. Freshly sampled undisturbed sediment cores were incubated over 8h and maintained at their sampling temperatures to evaluate the influence of low temperatures on the denitrification rate. From 2 to 12 degrees C, average denitrification rate and dissolved oxygen consumption increased from 9.6 to 25.5 micromol N2 m-2 h-1 and from 1.3 to 1.8 mmol O2 m-2 h-1, respectively, with no statistical dependence of temperature (p>0.05). Nitrification has been identified as the major nitrate source for denitrification, supplying more than 80% of the nitrate demand. Because no more than 31% of the nitrate removed by sediment is estimated to be denitrified, the presence of a major nitrate sink in sediment is suspected. Among possible nitrate consumption mechanisms, dissimilatory reduction of nitrate to ammonium, metal and organic matter oxidation processes are discussed. Providing the first measurements of denitrification rate in a St. Lawrence Estuary salt marsh, this study evidences the necessity of preserving and restoring marshes. They constitute an efficient geochemical filter against an excess of nitrate dispersion to coastal waters even under cold northern conditions. PMID:17276505

Poulin, Patrick; Pelletier, Emilien; Saint-Louis, Richard

2007-06-01

10

Cancer in wildlife, a case study: beluga from the St. Lawrence estuary, Qu?bec, Canada.  

PubMed Central

A population of approximately 650 beluga (Delphinapterus leucas) inhabits a short segment of the St. Lawrence estuary (SLE). Over 17 years (1983-1999), we have examined 129 (or 49%) of 263 SLE beluga carcasses reported stranded. The major primary causes of death were respiratory and gastrointestinal infections with metazoan parasites (22%), cancer (18%), and bacterial, viral, and protozoan infections (17%). We observed cancer in 27% of examined adult animals found dead, a percentage similar to that found in humans. The estimated annual rate (AR) of all cancer types (163/100,000 animals) is much higher than that reported for any other population of cetacean and is similar to that of humans and to that of hospitalized cats and cattle. The AR of cancer of the proximal intestine, a minimum figure of 63 per 100,000 animals, is much higher than that observed in domestic animals and humans, except in sheep in certain parts of the world, where environmental contaminants are believed to be involved in the etiology of this condition. SLE beluga and their environment are contaminated by polycyclic aromatic hydrocarbons (PAHs) produced by the local aluminum smelters. The human population living in proximity of the SLE beluga habitat is affected by rates of cancer higher than those found in people in the rest of Québec and Canada, and some of these cancers have been epidemiologically related to PAHs. Considered with the above observations, the exposure of SLE beluga to PAHs and their contamination by these compounds are consistent with the hypothesis that PAHs are involved in the etiology of cancer in these animals. PMID:11882480

Martineau, Daniel; Lemberger, Karin; Dallaire, Andre; Labelle, Philippe; Lipscomb, Thomas P; Michel, Pascal; Mikaelian, Igor

2002-01-01

11

Immune competence of rats fed with beluga whale blubber from the contaminated St. Lawrence estuary  

SciTech Connect

Over the last decades, high concentrations of environmental contaminants such as PCBs have been measured in the tissues of many species of marine mammals from different parts of the world. Even though many deleterious effects of these compounds have been reported in laboratory animals, the overall risk associated with these contaminants in wild animals is still not clearly understood. However, necropsy of St. Lawrence belugas showed numerous severe and disseminated infections with rather mildly pathogenic bacteria. Moreover, 37% of all the tumors reported in cetaceans were observed in St. Lawrence beluga whales. Indeed, both observations suggest immunosuppression. The aim of the study was to determine if contaminants present in fat tissues of belugas might provoke deleterious effect to their immune system if, under some circumstances, they are released into the circulation. To assess their immunotoxic potential, rats were fed for two months on a diet in which the lipids originated from the blubber of either highly polluted St. Lawrence belugas or relatively uncontaminated arctic belugas. Then, multiple immune responses were monitored. Those include phagocytosis, plaque forming cells, oxidative burst, natural killer cells, immunophenotyping and mitogenic assay. The results obtained show that only the humoral response of rats was impaired by the treatment. By combining all this information, the authors propose possible mechanisms of action to explain potential long-term consequences of environmental pollution.

Brousseau, P.; Lapierre, P.; Guise, S. De; Beland, P.; Martineau, D.; Fournier, M. [Univ. of Quebec, Montreal, Quebec (Canada)

1995-12-31

12

A mtDNA analysis of spatiotemporal distribution of two sympatric larval populations of rainbow smelt ( Osmerus mordax ) in the St. Lawrence River estuary, Quebec, Canada  

Microsoft Academic Search

Ecological isolation through resource partitioning is invoked as a major factor for explaining the persistence of genetically distinct yet closely related sympatric populations. Two genetically distinct sympatric populations of anadromous rainbow smelt (Osmerus mordax) exist in the middle estuary of the St. Lawrence River. The persistence of these coexisting populations in sympatry is in conflict with current theoretical concepts predicting

Dany Pigeon; Julian J. Dodson; Louis Bernatchez

1998-01-01

13

PCBs and OCPs in male harbour, grey, harp and hooded seals from the Estuary and Gulf of St Lawrence, Canada.  

PubMed

Blubber samples from adult male harbour seals (Phoca vitulina) from the St Lawrence Estuary, and from grey (Halichoerus grypus), harp (Phoca groenlandica) and hooded (Cystophora cristata) seals from the Gulf of St Lawrence, were analysed for polychlorinated biphenyls (PCB) and organochlorinated pesticides (OCP). All seals were between 5 and 19 years of age, and mean ages were not statistically different among the seal species. Mean concentrations of sigmaPCB and mirex were significantly higher in harbour seals, while sigmaDDT concentrations were significantly higher in hooded seals than in the other species examined. Harbour and hooded seals had similar concentrations of sigmaCHLOR, which were higher than in grey and harp seals. SigmaHCH concentrations were significantly higher in harp seals than in harbour and hooded seals and they were significantly higher in harbour and grey seals than in hooded seals. Harp and grey seals had similar levels of HCB, which were significantly higher than in either hooded or harbour seals. Patterns of PCB congeners and individual OCPs varied considerably between the four species. In PCA plots harbour, harp and hooded seals were well separated from each other, while grey seals were separated from the other species by a smaller degree. Between species variations may be explained by their dissimilar migratory patterns, habitat use and proximity to sources of industrial and agricultural pollution, their dietary regime (trophic level and individual prey items) as well as possible variations in the seals' abilities to eliminate these compounds. PMID:12398323

Hobbs, Karen E; Lebeuf, Michel; Hammill, Mike O

2002-09-16

14

Benthic fluxes of dissolved organic nitrogen in the Lower St. Lawrence Estuary and implications for selective organic matter degradation  

NASA Astrophysics Data System (ADS)

The distribution of dissolved organic nitrogen (DON) and carbon (DOC) in sediment pore waters was determined at nine locations along the St. Lawrence Estuary and in the Gulf of St. Lawrence. The study area is characterized by gradients in the sedimentary particulate organic matter (POM) reactivity, bottom water oxygen concentrations, as well as benthic respiration rates. Based on pore water profiles we estimated the benthic diffusive fluxes of DON and DOC. Our results show that DON fluxed out of the sediments at significant rates (110 to 430 ?mol m-2 d-1). DON fluxes were positively correlated with sedimentary POM reactivity and sediment oxygen exposure time (OET), suggesting direct links between POM quality, aerobic remineralization and the release of DON to the water column. DON fluxes were on the order of 30% to 64% of the total benthic inorganic fixed N loss due to denitrification, and often exceeded the diffusive nitrate fluxes into the sediments. Hence they represented a large fraction of the total benthic N exchange. This result is particularly important in light of the fact that DON fluxes are usually not accounted for in estuarine and coastal zone nutrient budgets. The ratio of the DON to nitrate flux increased from 0.6 in the Lower Estuary to 1.5 in the Gulf. In contrast to DON, DOC fluxes did not show any significant spatial variation along the Laurentian Channel (LC) between the Estuary and the Gulf (2100 ± 100?mol m-2 d-1), suggesting that production and consumption of labile DOC components proceed at similar rates, irrespective of the overall benthic characteristics and the reactivity of POM. As a consequence, the molar C/N ratio of dissolved organic matter (DOM) in pore water and the overlying bottom water varied significantly along the transect, with lowest C/N in the Lower Estuary (5-6) and highest C/N (> 10) in the Gulf. We observed large differences between the C/N of pore water DOM with respect to POM, and the degree of the C- versus -N element partitioning seems to be linked to POM reactivity and/or redox conditions in the sediment pore waters. Our results thus highlight the variable effects selective OM degradation and preservation can have on bulk sedimentary C/N ratios, decoupling the primary source C/N signatures from those in sedimentary archives. Our study further underscores that the role of estuarine sediments as efficient sinks of bioavailable nitrogen is strongly influenced by the release of DON during early diagenetic reactions, and that DON fluxes from continental margin sediments represent an important internal source of N to the ocean.

Alkhatib, M.; del Giorgio, P. A.; Gelinas, Y.; Lehmann, M. F.

2013-05-01

15

Benthic fluxes of dissolved organic nitrogen in the lower St. Lawrence estuary and implications for selective organic matter degradation  

NASA Astrophysics Data System (ADS)

The distribution of dissolved organic nitrogen (DON) and carbon (DOC) in sediment porewaters was determined at nine locations along the St. Lawrence estuary and in the gulf of St. Lawrence. In a previous manuscript (Alkhatib et al., 2012a), we have shown that this study area is characterized by gradients in the sedimentary particulate organic matter (POM) reactivity, bottom water oxygen concentrations, and benthic respiration rates. Based on the porewater profiles, we estimated the benthic diffusive fluxes of DON and DOC in the same area. Our results show that DON fluxed out of the sediments at significant rates (110 to 430 ?mol m-2 d-1). DON fluxes were positively correlated with sedimentary POM reactivity and varied inversely with sediment oxygen exposure time (OET), suggesting direct links between POM quality, aerobic remineralization and the release of DON to the water column. DON fluxes were on the order of 30 to 64% of the total benthic inorganic fixed N loss due to denitrification, and often exceeded the diffusive nitrate fluxes into the sediments. Hence they represented a large fraction of the total benthic N exchange, a result that is particularly important in light of the fact that DON fluxes are usually not accounted for in estuarine and coastal zone nutrient budgets. In contrast to DON, DOC fluxes out of the sediments did not show any significant spatial variation along the Laurentian Channel (LC) between the estuary and the gulf (2100 ± 100 ?mol m-2 d-1). The molar C / N ratio of dissolved organic matter (DOM) in porewater and the overlying bottom water varied significantly along the transect, with lowest C / N in the lower estuary (5-6) and highest C / N (> 10) in the gulf. Large differences between the C / N ratios of porewater DOM and POM are mainly attributed to a combination of selective POM hydrolysis and elemental fractionation during subsequent DOM mineralization, but selective adsorption of DOM to mineral phases could not be excluded as a potential C / N fractionating process. The extent of this C- versus N- element partitioning seems to be linked to POM reactivity and redox conditions in the sediment porewaters. Our results thus highlight the variable effects selective organic matter (OM) preservation can have on bulk sedimentary C / N ratios, decoupling the primary source C / N signatures from those in sedimentary paleoenvironmental archives. Our study further underscores that the role of estuarine sediments as efficient sinks of bioavailable nitrogen is strongly influenced by the release of DON during early diagenetic reactions, and that DON fluxes from continental margin sediments represent an important internal source of N to the ocean.

Alkhatib, M.; del Giorgio, P. A.; Gelinas, Y.; Lehmann, M. F.

2013-11-01

16

Late-Wisconsinan submarine moraines along the north shore of the Estuary and Gulf of St. Lawrence (Eastern Canada)  

NASA Astrophysics Data System (ADS)

A series of ice-contact submarine fans and morainal banks along the Québec North-Shore of the Estuary and Gulf of St. Lawrence (Eastern Canada), between the Manicouagan River delta and the Mingan Islands, have been revealed with great detail by recent multibeam echosounder and high-resolution subbottom profiler surveys. These grounding-line landforms are observed between 65 and 190 m water depths and were constructed as the marine-based margin of the Laurentide Ice Sheet (LIS) stabilized or readvanced. Radiocarbon ages obtained from shells sampled in sediment cores collected in glaciomarine deposits 6 km south of a grounding line in the Sept-Iles area indicate a stabilisation that took place around 11 000 14C yr BP (12.5 ka cal BP with a ?R=120 ± 40 yr). In the Mingan Islands area, organic matter collected in distal deposits of an ice-contact fan is dated at 10 800 14C yr BP (11.6 ka cal BP). The position of the Sept-Iles and Mingan deposits, 20 km south of the ~9.7-9.5 14C kyr BP North-Shore Moraine, suggests that these ice marginal landforms were constructed during the Younger Dryas (YD) cold episode and that they might be the eastward submarine extent of the early YD St. Narcisse morainic system. Superimposed till sheets and morainal banks observed within grounding line deposits indicate that this stability phase was interrupted by local readvances that were marked in some cases by ice streaming. Segments of this morainic system are also visible along the shoreline in some sectors, where they have been generally washed out of fine fragments by waves. Another series of ice-contact deposits and landforms of similar nature observed farther offshore and at greater depths (100-190 m) were formed during a previous phase of stabilisation of the LIS margin. This older morainic system was probably deposited immediately after the opening of the Estuary and Gulf of the St. Lawrence.

Lajeunesse, Patrick; St-Onge, Guillaume

2013-04-01

17

ST. LAWRENCE RIVER BASIN  

E-print Network

#12;983 22 ST. LAWRENCE RIVER BASIN system can travel at least 3260km from western Lake Superior the river system draws sustenance from nine states (Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio to 9000 years the St. Lawrence River­Great Lakes system has played an important role in the lives of many

Thorp, James H.

18

Congener-specific analysis of the accumulation of polychlorinated biphenyls (PCBs) by aquatic organisms in the maximum turbidity zone of the St. Lawrence estuary, Québec, Canada.  

PubMed

The polychlorinated biphenyl (PCB) contamination of the biota of the St. Lawrence estuary maximum turbidity zone (MTZ) was investigated. The species analyzed consist of zooplankton (mostly Neomysis americana), larval smelt (Osmerus mordax), juvenile smelt, juvenile tomcod (Microgadus tomcod) and adult smelt, tomcod and capelin (Mallotus villosus). A significant increase in total PCB contamination from zooplankton to all fish developmental stages indicates that the St. Lawrence MTZ is a site of significant PCB contamination. The total PCB contamination of adult smelt and tomcod sampled in the St. Lawrence MTZ was greater than the limit of 0.1 ppm set by the International Joint Commission for the protection of predators. For zooplankton, tomcod and capelin, significant correlations were found between lipid content and PCB contamination. The congener-specific analyses showed that the bioconcentration factor of the individual congeners varied with the species involved and with the molecular structure of the congener. It was found that the chlorine atoms in positions 2, 4 and 5 on at least one phenyl ring of the PCB molecule was a dominant factor causing accumulation of PCBs in aquatic organisms. The pattern of PCB congeners found in beluga (Delphinapterus leucas) whale tissues is similar to the PCB pattern found in the St. Lawrence estuary MTZ biota. PMID:2128134

Gagnon, M M; Dodson, J J; Comba, M E; Kaiser, K L

1990-11-01

19

Abundance of larval rainbow smelt ( Osmerus mordax ) in relation to the maximum turbidity zone and associated macroplanktonic fauna of the middle St. Lawrence estuary  

Microsoft Academic Search

We tested the hypothesis that the distribution and retention of larval smelt (Osmerus mordax) in the middle estuary of the St. Lawrence River is related to the maintenance of other planktonic organisms in the maximum\\u000a turbidity zone (MTZ). We documented the horizontal and vertical distribution of larval smelt, macrozooplankton, and suspended\\u000a particulate matter over four tidal cycles at each of

Julian J. Dodson; Jean-Claude Dauvin; R. Grant Ingram; B. d’Anglejan

1989-01-01

20

The Effects of Recent Floods and Geomorphic Processes on Red Ash Populations, Upper St Lawrence Estuary, Québec  

NASA Astrophysics Data System (ADS)

Effects of recent floods on red ash ( Fraxinus pennsylvanica Marsh.) forest margins were studied along the upper St Lawrence Estuary in eastern Canada. Major floods amplified by tides left many injuries on riparian red ash trees, which allows dating of past disturbances based on stand structure and dendrochronological analysis. The formation of ice scars on stems, the development of basal sprouts, and the inhibition of population regeneration on shore, provide evidence of a recent increase in shore disturbance. Since the 1950s and especially the 1970s, a landward displacement of the tree line occurred as a result of increasing shore erosion. Usually the ice foot on the shore disintegrates in situ in April, but since the 1950s, early snow-melts in mid-winter have been causing sudden floods that raise the ice foot to the edge of the backshore forest, leaving many signs of damage. Increasing winter climatic variability since the 1950s seems responsible for such variations in flood regime.

Langlais, Dominique; Bégin, Yves

1993-11-01

21

Spatial distribution and viability of Alexandrium tamarense resting cysts in surface sediments from the St. Lawrence Estuary, Eastern Canada  

NASA Astrophysics Data System (ADS)

The dinoflagellate Alexandrium tamarense Group 1 (as defined by Lilly et al., 2007) is responsible for recurrent outbreaks of paralytic shellfish poisoning (PSP) in the St. Lawrence Estuary (SLE), Eastern Canada. In August 2008, a major bloom of A. tamarense developed in the SLE and caused major mortality of fish, seabirds and marine mammals notably in the vicinity of a marine park. Eleven months later, surface (0-5 cm) and deeper (5-10 cm) sediments were sampled to determine resting cysts concentrations, locate prospective cyst seedbeds and examine if these had changed following this major bloom. This information is thought to be important to understand inter-annual patterns in algal toxicity, cyst abundance being a good predictor of subsequent bloom magnitude in some regions. Surface cyst distribution was heterogeneous and it confirmed the location of the cyst seedbed previously reported on the north shore near the Manicouagan/aux-Outardes Rivers (>500 cysts cm-3). A zone of cyst accumulation was also observed on the south shore of the SLE (maximum of 1200 cysts cm-3), with higher concentrations relative to previous cyst mapping in the 1980s. A mismatch was observed between the zones with high surface cyst concentrations and those where the highest PSP toxins were detected (used as a proxy for vegetative cells in the water column). Cyst concentrations were negatively correlated with PSP levels from the same sites, suggesting that cysts were formed and deposited away from the major sites of toxicity. Deposition likely took place near the end of the bloom, once it had reached the eastern boundary of the SLE. PSP toxicity was worse near the peak of the bloom, which occurred westward of this region. This highlights the dynamic behaviour of local blooms, influenced by the estuarine and mesoscale circulation. Interestingly, the major bloom of August 2008 was not followed by particularly large cyst deposition or by any major bloom in 2009 in this region. Cyst viability was also examined, using Sytox Green, and found to be highest (nearly 100%) in the sites where cyst concentrations were maximum. Our results call for further investigation of the cyst mapping hypothesis in the St. Lawrence, where the local circulation seems to have an overriding influence on cyst deposition patterns.

Gracia, Stéphanie; Roy, Suzanne; Starr, Michel

2013-04-01

22

Holocene paleomagnetic records from the St. Lawrence Estuary, eastern Canada: centennial-to millennial-scale  

E-print Network

- to millennial-scale geomagnetic modulation of cosmogenic isotopes Guillaume St-Onge a;Ã? , Joseph S. Stoner b;1 favorably with North American and European Holocene RPI records at millennial and even some centennial the millennial- and even some centennial-scale variability within cosmogenic isotope records. This implies

St-Ong, Guillaume

23

Holocene Relative Paleointensity Record From the St. Lawrence Estuary, Eastern Canada: Millennial to Centennial-scale Variability of the Global Scale Geomagnetic Field  

Microsoft Academic Search

Two long piston cores (MD99-2220: Lat. 48°38.32N, Long. 68°37.93W, water depth 320 m, length 51.6 m and MD99-2221: Lat. 48°10.60N, Long. 69°30.35W, water depth 212 m, length 31.0 m) were raised from the St. Lawrence Estuary, Eastern Canada because of the expanded Holocene sediment sequence this location provides. A u-channel based paleomagnetic study, augmented by AMS 14C dates, rock-magnetic and

J. S. Stoner; C. Hillaire-Marcel

2002-01-01

24

Instability of a buoyancy-driven coastal jet; The Gaspé Current and its St. Lawrence Precursor  

Microsoft Academic Search

The discharge of the St. Lawrence River drives a buoyant jet which extends along the south shore of the lower St. Lawrence estuary and, combining with the northwest Gulf of St. Lawrence cyclonic gyre, becomes the Gaspé Current. In both the estuarine jet and the Gaspé Current, strong lateral and vertical shears are present. Satellite thermal imagery has shown that

Gordon Mertz; Mohammed I. El-Sabh; Denis Proulx; Alfonso R. Condal

1988-01-01

25

Reproductive System Impairment of Mice Fed Diets Containing Beluga Whale Blubber from the St. Lawrence Estuary and Arctic Populations  

Microsoft Academic Search

The toxic potential of naturally relevant mixtures of PCBs and other organohalogens on the reproductive system of C57Bl\\/6 female mice was assessed. Mice were fed diets in which lipids were replaced by blubber of beluga whales from a highly contaminated population of the Saint Lawrence River, and a less contaminated population from the Arctic Ocean. Ratios of blubber from both

Sylvia Ruby; Luz Tavera Mendoza; Michel Fournier; Pauline Brousseau; V. Dégas

2003-01-01

26

Benthic nutrient fluxes along the Laurentian Channel: Impacts on the N budget of the St. Lawrence marine system  

E-print Network

. Lawrence estuary geochemistry nitrogen cycle denitrification a b s t r a c t Water column concentrations. Lawrence and the Upper and Lower St. Lawrence Estuary (USLE and LSLE, respectively) to assess the nitrogen and benthic fluxes of dissolved inorganic nitrogen (DIN) and oxygen (DO) were measured in the Gulf of St

Long, Bernard

27

Immunosuppression in mice fed on diets containing beluga whale blubber from the St Lawrence Estuary and the Arctic populations  

Microsoft Academic Search

In order to assess the immunotoxic potential of naturally relevant mixtures of PCBs and other organohalogens, C57Bl\\/6 mice were fed on diets in which lipids were replaced by blubber of beluga whales from the highly contaminated population of the Saint-Lawrence River, and the less contaminated population from the Arctic. Different ratios of blubber from both sources were mixed in order

M Fournier; V Dégas; T Colborn; F. O Omara; F Denizeau; E. F Potworowski; P Brousseau

2000-01-01

28

Late-Quaternary morpho-sedimentology and submarine mass movements of the Betsiamites area, Lower St. Lawrence Estuary, Quebec, Canada  

E-print Network

Late-Quaternary morpho-sedimentology and submarine mass movements of the Betsiamites area, Lower St 2008 Accepted 4 March 2008 Keywords: submarine mass movements morpho-sedimentology multibeam bathymetry the submarine morpho-sedimentology of an area of 500 km2 with focus on the consequences of four mass movement

St-Ong, Guillaume

29

Levels and temporal trends (1988-1999) of polybrominated diphenyl ethers in beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary, Canada.  

PubMed

Polybrominated diphenyl ethers (PBDEs) were determined in blubber samples of 54 stranded adult beluga whales (Delphinapterus leucas) collected between 1988 and 1999 in the St. Lawrence Estuary (SLE), Quebec, Canada. Summed concentrations of 10 PBDE congeners (sigmaPBDEs) measured in beluga samples varied between 20 and almost 1000 ng/g wet weight. According to the PBDE concentrations in marine mammals reported in the scientific literature, SLE belugas appear to be relatively lightly contaminated. Only a few predominant congeners (namely, PBDE-47, -99, and -100) represent on average more than 75% of sigmaPBDEs in SLE belugas. The accumulation of sigmaPBDEs in both male and female belugas showed significant exponential increase throughout the 1988-1999 time period. The time necessary for beluga to double their blubber concentration of the most prevalent PBDE congeners was no longer than 3 years. The PBDE temporal changes reported in this study are generally faster but in agreement with the trend observed in other organisms collected in Canada, such as lake trout (Salvelinus namaycush) from the Great Lakes, ringed seal (Phoca hispida), and beluga whale from the Canadian Arctic. Some changes in the pattern of PBDEs in belugas were also observed during the time period investigated. The recent and important increase of PBDE levels in SLE belugas could explain the unexpected lack of statistical difference in PBDE contamination between males and females. This suggests that to date PBDEs tend to be accumulated by both male and female belugas, masking the elimination of PBDEs by females through post-natal transfer to their offspring. This study confirms that the growing use of PBDEs as flame retardants has resulted in rising contamination of Canadian aquatic environments. Additional studies are needed to assess the toxicological implications of the PBDE tissue levels found in SLE belugas. PMID:15224724

Lebeuf, Michel; Gouteux, Bruno; Measures, Lena; Trottier, Steve

2004-06-01

30

Humic acids from particulate organic matter in the Saguenay Fjord and the St. Lawrence Estuary investigated by advanced solid-state NMR  

NASA Astrophysics Data System (ADS)

Detailed structural information on two humic acids extracted from two sinking particulate matter samples at a water depth of 20 m in the Saguenay Fjord (F-20-HA) and the St. Lawrence Estuary (E-20-HA) (Canada), was obtained by advanced solid-state NMR. Spectral-editing analyses provided numerous structural details rarely reported in geochemical studies. The NMR data account almost quantitatively for the elemental compositions. The two humic acids were found to be quite similar, consisting of four main structural components: peptides (ca. 39 ± 3% vs. 34 ± 3% of all C for E-20-HA and F-20-HA, respectively); aliphatic chains, 14-20 carbons long (ca. 25 ± 5% vs. 17 ± 5% of all C); aromatic structures (ca. 17 ± 2% vs. 26 ± 2% of all C); and sugar rings (14 ± 2% vs. 15 ± 2% of all C). Peptides were identified by 13C{ 14N} SPIDER NMR, which selects signals of carbons bonded to nitrogen, and by dipolar DEPT, which selects CH-group signals, in particular the NCH band of peptides. The SPIDER spectra also indicate that heterocycles constitute a significant fraction of the aromatic structures. The aliphatic (CH 2) n chains, which are highly mobile, contain at least one double bond per two chains and end in methyl groups. 1H spin diffusion NMR experiments showed that these mobile aliphatic chains are in close (<10 nm) proximity to the other structural components. A major bacterial contribution to these two samples could explain why the samples, which have different dominant organic matter sources (terrestrial vs. marine), are similar to each other as well as to degraded algae and particles from other waters. The NMR data suggest structures containing mobile lipids in close proximity to peptides and carbohydrates (e.g., peptidoglycan) as found in bacterial cell walls. Measured yields of muramic acid and D-amino acids confirmed the presence of bacterial cell wall components in the studied samples.

Mao, J.-D.; Tremblay, L.; Gagné, J.-P.; Kohl, S.; Rice, J.; Schmidt-Rohr, K.

2007-11-01

31

Mid and late Holocene dust deposition in eastern Canada - a preliminary multi-proxy record from the Baie bog (St. Lawrence Estuary, Quebec)  

NASA Astrophysics Data System (ADS)

Atmospheric mineral dust plays an important role in the Earth's climate through parameters such as atmospheric radiation, cloud properties and biogeochemical cycles. However, the high spatial and temporal variability of mineral dust and a lack of terrestrial archives in certain regions limit our understanding global dust-climate interactions. Ombrotrophic peatlands (bogs; atmospherically-fed only) are increasingly recognized as archives of atmospheric dust deposition. Their global distribution and high accumulation rates (i.e. high resolution) over the Holocene make them suitable substitute to marine and/or ice records. The Baie bog, located along the St. Lawrence Estuary (North Shore region, Quebec, Canada), was sampled to investigate dust deposition/palaeowinds in north eastern North America over the mid and late Holocene. The core was subsampled for elemental and isotopic geochemistry as well as particle size analyses, 210Pb and radiocarbon dating. Radiocarbon dating of the base of the peat sequence yielded an age of about 4300 yr cal BP. Initial results show periods of increased dust flux, calculated from REE concentrations, between 1000-1500 yr cal BP and 100-500 yr cal BP in the peat profile from 0.5 to 4 g m-2 yr-1. Higher dust fluxes usually occur in combination with greater particle size suggesting either stronger winds or a change of source. Periods of increased dust fluxes in the profile also correspond with changes in the macrofossil assemblages. A first attempt at source tracing through preliminary radiogenic isotopes analyses (Pb, Nd; ongoing) will also be discussed.

Pratte, Steve; Garneau, Michelle; De Vleeschouwer, François

2014-05-01

32

Reproductive system impairment of mice fed diets containing beluga whale blubber from the St Lawrence estuary and arctic populations.  

PubMed

The toxic potential of naturally relevant mixtures of PCBs and other organohalogens on the reproductive system of C57Bl/6 female mice was assessed. Mice were fed diets in which lipids were replaced by blubber of beluga whales from a highly contaminated population of the Saint Lawrence River, and a less contaminated population from the Arctic Ocean. Ratios of blubber from both sources were mixed in order to perform a dose-response study. Control mice were fed diets for 90 d in which fat was replaced by corn oil or beef tallow. There were no significant effects of diets on body, liver, spleen or thymus weights. Similarly ovulation occurred in all control and experimental groups. However, Graafian follicles from ovaries of mice fed contaminated diets showed abnormal development of oocytes. Cumulus granulosa cells bind normally to the oocyte prior to ovulation and are essential for sperm penetration and fertilization. These cells were absent in both Graafian follicles and ovulated oocytes in the oviduct of all groups fed contaminated diets. Oviducts of these mice revealed evidence of epithelial degeneration. These results suggest the female mouse reproductive system is sensitive to organohalogens and illustrate the toxic potential of contaminant mixtures as found in the less contaminated Arctic population. PMID:12775517

Ruby, Sylvia; Mendoza, Luz Tavera; Fournier, Michel; Brousseau, Pauline; Dégas, V

2003-06-13

33

Immunosuppression in mice fed on diets containing beluga whale blubber from the St Lawrence estuary and the Arctic populations.  

PubMed

In order to assess the immunotoxic potential of naturally relevant mixtures of PCBs and other organohalogens, C57Bl/6 mice were fed on diets in which lipids were replaced by blubber of beluga whales from the highly contaminated population of the Saint-Lawrence River, and the less contaminated population from the Arctic. Different ratios of blubber from both sources were mixed in order to allow a dose-response study. Mice were fed for a period of 90 days at the end of which their immunological status was monitored. For general parameters such as body weight, weight of the spleen and the thymus no significant effect of diets were observed. The immunological endpoints such as the blastic transformation of splenocytes and the spleen NK cell activity were not significantly affected by any of the diets compared to control diets. While the different cell subpopulations of peripheral blood and thymus were not affected by the diets, a significant decrease was noted in the CD8+ T cell population in the spleen of mice fed with most of the diets containing beluga blubber. Moreover, the ability of splenic cells to elicit humoral response against sheep red blood cells as well as the potential of peritoneal macrophages to perform phagocytosis were suppressed by all diets containing beluga blubbers. In summary, there was no differences between the groups fed with a blubber diet with low and high organochlorine contamination. However, a clear immunosuppression was demonstrated when these groups were compared to the group fed with beef oil. Despite the fact that we cannot exclude a possible contribution of the fatty acid composition of the beluga blubber to the immunosupression, these results suggest the sensitivity of mouse immune system towards organohalogens, and point out the toxic potential of contaminant mixtures as found in the less contaminated Arctic population. PMID:10720746

Fournier, M; Dégas, V; Colborn, T; Omara, F O; Denizeau, F; Potworowski, E F; Brousseau, P

2000-03-15

34

Dissolved mercury behaviour in the Saint Lawrence estuary  

NASA Astrophysics Data System (ADS)

Dissolved mercury concentrations have been measured in the waters of the St Lawrence estuary. The typical concentration of the riverine end-member is 12·0±3·0 p M; the oceanic end-member samples exhibit a mean mercury concentration of 2·4 p M. The graphical pattern of the relationship between mercury concentration and salinity shows a departure from a dilution line. We suggest that a removal of mercury from the dissolved phase during the estuarine mixing is responsible for this observation. Based on the results, the actual input of dissolved mercury from the St Lawrence River to the Gulf is evaluated to be approximately 0·52 T a -1.

Cossa, Daniel; Gobeil, Charles; Courau, Philippe

1988-02-01

35

Cooling in the Gulf of St. Lawrence and estuary region at 9.7 to 7.2 14C ka (11.2–8.0 cal ka): Palynological response to the PBO and 8.2 cal ka cold events, Laurentide Ice Sheet air-mass circulation and enhanced freshwater runoff  

Microsoft Academic Search

An examination of post-Younger Dryas (YD) pollen stratigraphies in the Gulf of St. Lawrence and St. Lawrence estuary region reveals features in the pollen records that represent breaks in the normal vegetation succession, widespread vegetation suppression, and a delay in migration of plant taxa between 9.7 and 7.2 14C ka (11.2 and 8.0 cal ka). The domination of Alnus crispa at

Thane W. Anderson; Elisabeth Levac; C. F. Michael Lewis

2007-01-01

36

Invasion of the southern Gulf of St. Lawrence by the clubbed tunicate ( Styela clava Herdman): Potential mechanisms for invasions of Prince Edward Island estuaries  

Microsoft Academic Search

All but one of the nine non-native marine species that established populations in the southern Gulf of St. Lawrence (sGSL) in the past decade initially invaded the sGSL via coastal and estuarine waters of Prince Edward Island (PEI). Almost half of these species are tunicates, and all but one still occur only in PEI. Recent introductions include Styela clava Herdman

Andrea Locke; J. Mark Hanson; Karla M. Ellis; Jason Thompson; Rémy Rochette

2007-01-01

37

Assessment of Salinity-Related Mortality of Freshwater Bacteria in the Saint Lawrence Estuary  

Microsoft Academic Search

ThegrowthresponseoffreshwaterbacteriafromtheSt.LawrenceRiver,exposedtobrackishwaters(salinity of 0 to 20‰) from the upper estuary, was assessed by a methodology requiring the combined use of dilution cultures and diffusion chambers. The longitudinal distribution of bacterial abundance in waters within this salinityrangewasalsoexamined.Growthofthefreshwaterbacteriawasreducedby15and50%afterexposure tosalinitiesof10and20‰,respectively.Atlowersalinities,nogrowthreductionwasobserved,andatasalinity of 2‰, growth was even stimulated. Longitudinal distribution data showed that bacterial abundance also peaked at this salinity. In contrast with an earlier hypothesis,

JEAN PAINCHAUD; JEAN-CLAUDE THERRIAULT; ANDLOUIS LEGENDRE

1995-01-01

38

The Earth Sciences at St. Lawrence University?  

ERIC Educational Resources Information Center

The elimination of traditional courses in favor of student-originated, self-graded projects in the Department of Geology and Geography at St. Lawrence University in Canton (New York) proved too radical for the entire faculty. The program eventually became two-tracked, offering students both traditional and student-generated learning situations.…

Romey, William D.

1983-01-01

39

The St. Lawrence University Adirondack Semester  

ERIC Educational Resources Information Center

This article features St. Lawrence University's Adirondack Semester, a small program, with enrollment limited to twelve students. The participants of the program are composed of a small group of students with shared interests and serious purpose, living harmoniously and mostly free from the temptations and distractions of the larger world,…

Johnson, Baylor; Alexander, Steve

2009-01-01

40

Sivuqam Ungipaghaatangi (St. Lawrence Island Legends).  

ERIC Educational Resources Information Center

Transmitted orally for generations until the Eskimo language became a written one, the eleven St. Lawrence Island legends compiled in this volume for high school students tell of feats that were accomplished through supernatural power. Meant for both entertainment and instruction, the tales convey wise council indirectly through the conversations…

Slwooko, Grace

41

St. Lawrence Island Eskimo Phonology and Orthography  

ERIC Educational Resources Information Center

Central Siberian Yupik Eskimo is the language both of the natives of St. Lawrence Island and of the facing Siberian mainland, with few minor variations. A history of the language is given as it evolved in both countries, as well as a phonological analysis and orthographic developments on both sides. (SCC)

Krauss, Michael E.

1975-01-01

42

Instability of a buoyancy-driven coastal jet; The Gaspé Current and its St. Lawrence Precursor  

NASA Astrophysics Data System (ADS)

The discharge of the St. Lawrence River drives a buoyant jet which extends along the south shore of the lower St. Lawrence estuary and, combining with the northwest Gulf of St. Lawrence cyclonic gyre, becomes the Gaspé Current. In both the estuarine jet and the Gaspé Current, strong lateral and vertical shears are present. Satellite thermal imagery has shown that the Gaspé Current is unstable. Its instabilities are manifested as prominent wave disturbances and eddy features. We use satellite thermal images from 3 different years to show that unstable disturbances are also characteristic of the estuarine jet. We update previous work to show that Gaspé Current is both baroclinically and barotropically unstable. Our model studies also show that this conclusion is valid for the estuarine jet as well. Finally, we discuss a sequence of satellite images showing the development of an unstable disturbance apparently triggered by an eastward wind pulse.

Mertz, Gordon; El-Sabh, Mohammed I.; Proulx, Denis; Condal, Alfonso R.

1988-06-01

43

Possible mechanisms of action of environmental contaminants on St. Lawrence beluga whales (Delphinapterus leucas).  

PubMed Central

A small isolated population of beluga whales (Delphinapterus leucas) that are highly contaminated by pollutants, mostly of industrial origin, resides in the St. Lawrence estuary, Québec, Canada. Overhunting in the first half of the century was the probable cause for this population to dwindle from several thousand animals to the current estimate of 500. The failure of the population to recover might be due to contamination by organochlorine compounds, which are known to lead to reproductive failure and immunosuppression in domestic and laboratory animals and seals. Functional and morphological changes have been demonstrated in thyroid gland and adrenal cortex in many species exposed to organochlorinated compounds, including seals. Morphological lesions, although different, were also found in belugas. Functional evaluation of thyroid and adrenal glands of contaminated (St. Lawrence) versus much less contaminated (Arctic) belugas is currently under way. Necropsy of St. Lawrence belugas showed numerous severe and disseminated infections with rather mildly pathogenic bacteria, which suggests immunosuppression. Organochlorine compounds and other contaminants found in beluga whales cause immunosuppression in a variety of animal species including seals. Thirty-seven percent of all the tumors reported in cetaceans were observed in St. Lawrence beluga whales. This could be explained by two different mechanisms: high exposure to environmental carcinogens and suppression of immunosurveillance against tumors. Overall, St. Lawrence belugas might well represent the risk associated with long-term exposure to pollutants present in their environment and might be a good model to predict health problems that could emerge in highly exposed human populations over time. PMID:7556028

De Guise, S; Martineau, D; Beland, P; Fournier, M

1995-01-01

44

Methylsulfone polychlorinated biphenyl and 2,2-bis(chlorophenyl)-1,1-dichloroethylene metabolites in beluga whale (Delphinapterus leucas) from the St. Lawrence River estuary and western Hudson Bay, Canada  

SciTech Connect

Knowledge is limited regarding methylsulfone (MeSO{sub 2})-polychlorinated biphenyl (PCB), and especially MeSo{sub 2}-2,2-bis(chlorophenyl)-1,1-dichloroethylene (DDE), metabolites in cetacean species. The authors hypothesized that the ability of beluga whale (Delphinapterus leucas) to biotransform PCB and DDE compounds, and to form and degrade their MeSO{sub 2}-PCB and -DDE metabolites, is related to the capacity for xenobiotic metabolism. Adipose biopsies were collected from male and female beluga whale from distinct populations in the St. Lawrence River estuary (STL) and western Hudson Bay (WHB), Canada, which are contrasted by the exposure to different levels of cytochrome P450 enzyme-inducing, chlorinated hydrocarbon contaminants. The PCBs, DDTs, DDEs, 28 MeSO{sub 2} metabolites of 14 meta-para chlorine-unsubstituted PCBs, and four MeSO{sub 2} metabolites of 4,4{prime}- and 2,4{prime}-DDE were determined. The mean concentrations of total ({Sigma}-) MeSO{sub 2}-PCB in male STL beluga (230 ng/g), and ratios of {Sigma}-MeSO{sub 2}-PCB to {Sigma}-PCB (0.05) and {Sigma}-precursor-PCB (0.17) were approximately twofold higher, whereas the {Sigma}-precursor-PCB to {Sigma}-PCB ratio was approximately twofold lower, than in male WHB beluga. Both populations had a low formation capacity for MeSO{sub 2}-PCBs with {le} six chlorines (<4% of {Sigma}-MeSO{sub 2}-PCBs). The congener patterns were dominated by trichloro- and tetrachloro-MeSO{sub 2}-PCBs, and tetrachloro- and pentachloro-MeSO{sub 2}-PCBs in WHB and STL animals, respectively. In addition to 2- and 3-MeSO{sub 2}-4,4{prime}-DDE, two unknown MeSO{sub 2}-2,4{prime}-DDEs were detected. The mean 3-MeSO{sub 2}-4,4{prime}-DDE concentration in STL beluga (1.2 ng/g) was much greater than in WHB animals. The concentrations of 4,4{prime}-DDE, and not 3-MeSO{sub 2}-4,4{prime}-DDE, increased with age in male STL animals. The authors demonstrated that sulfone formation and clearance is related to metabolic capacity, and thus PCB, DDE, and MeSO{sub 2}-PCB and -DDE toxicokinetics differ for STL and WHB beluga. In the past, the capacity of odontocetes for PCB and DDE biotransformation leading to persistent sulfone formation and clearance is related to metabolic capacity, and thus PCB, DDE, and MeSO{sub 2}-PCB and -DDE toxicokinetics differ for STL and WHB beluga. In the past, the capacity of odontocetes for PCB and DDE biotransformation leading to persistent sulfone metabolites has been underestimated. More information is needed for other cetacean species and marine mammals. The results of this study indicate that MeSO{sub 2}-PCBs and -DDEs need to be included in the toxicologic risk assessment of PCB and DDT exposure in odontocetes, and perhaps for cetaceans in general.

Letcher, R.J.; Norstrom, R.J.; Muir, D.C.G.; Sandau, C.D.; Koczanski, K.; Michaud, R.; De Guise, S.; Beland, P.

2000-05-01

45

Regional and Seasonal Inputs of Mercury into Lake St. Pierre (St. Lawrence River), a Major Commercial  

E-print Network

Regional and Seasonal Inputs of Mercury into Lake St. Pierre (St. Lawrence River), a Major Lake St. Pierre (LSP), constituted of a 120 km2 stretching of the St. Lawrence River (Southern Québec), hosts the largest freshwater fishery industry in Canada. The lake drains, through its main tributaries

Long, Bernard

46

Lobsters and crabs as potential vectors for tunicate dispersal in the southern Gulf of St. Lawrence, Canada  

Microsoft Academic Search

Following anecdotal reports of tunicates on the carapaces of rock crab (Cancer irroratus) and American lobster (Homarus americanus), we evaluated the role of these species and northern lady crab Ovalipes ocellatus as natural vectors for the spread of invasive tunicates in the southern Gulf of St. Lawrence. Several hundred adult specimens of crabs and lobster from two tunicate- infested estuaries

Renée Y. Bernier; Andrea Locke; John Mark Hanson

2009-01-01

47

An empirical approach to the remote sensing of the chlorophyll in the optically complex waters of the Estuary and Gulf of Saint-Lawrence  

Microsoft Academic Search

Data from five research cruises performed between 1997 and 2001 were processed in order to investigate the potential for improving remote sensing algorithms in the Estuary and Gulf of St. Lawrence. Measured in situ parameters included concentration-dependent indicators of the three critical, optically-active constituents, chlorophyll, Coloured Dissolved Organic Matter (CDOM) and Suspended Particulate Matter (SPM). The radiometric dataset used to

K. Mehmet Yayla

2009-01-01

48

St. Lawrence blue whale vocalizations revisited: characterization of calls detected from 1998 to 2001.  

PubMed

From 1998 to 2001, 115 h of acoustic recordings were made in the presence of the well-studied St. Lawrence population of blue whales, using a calibrated omnidirectional hydrophone [flat (+/- 3 dB) response from 5 to 800 Hz] suspended at 50 m depth from a surface isolation buoy. The primary field site for this study was the estuary region of the St. Lawrence River (Québec, Canada), with most recordings made between mid-August and late October. During the recordings, detailed field notes were taken on all cetaceans within sight. Characterization of the more than 1000 blue whale calls detected during this study revealed that the St. Lawrence repertoire is much more extensive than previously reported. Three infrasonic (<20 Hz) and three audible range (30-200 Hz) call types were detected, with much time/frequency variation seen within each type. Further variation is seen in the form of call segmentation, which appears (through examination of Lloyd's Mirror interference effects) to be controlled at least partially by the whales. Although St. Lawrence blue whale call characteristics are similar to those of the North Atlantic, comparisons of phrase composition and spacing among studies suggest the possibility of population dialects within the North Atlantic. PMID:17069329

Berchok, Catherine L; Bradley, David L; Gabrielson, Thomas B

2006-10-01

49

Evaluation of the contamination of marine algae (seaweed) from the St. Lawrence River and likely to be consumed by humans  

SciTech Connect

The goal of the study was to assess the contamination of marine algae (seaweeds) growing in the St. Lawrence River estuary and Gulf of St. Lawrence and to evaluate the risks to human health from the consumption of these algae. Algae were collected by hand at low tide. A total of 10 sites on the north and south shores of the St. Lawrence as well as in Baie des Chaleurs were sampled. The most frequently collected species of algae were Fucus vesiculosus, Ascophyllum nodosum, Laminaria Longicruris, Palmaria palmata, Ulva lactuca, and Fucus distichus. Alga samples were analyzed for metals iodine, and organochlorines. A risk assessment was performed using risk factors. In general, concentrations in St. Lawrence algae were not very high. Consequently, health risks associated with these compounds in St. Lawrence algae were very low. Iodine concentration, on the other hand, could be of concern with regard to human health. Regular consumption of algae, especially of Laminaria sp., could result in levels of iodine sufficient to cause thyroid problems. For regular consumers, it would be preferable to choose species with low iodine concentrations, such as U. lactuca and P. palmata, in order to prevent potential problems. Furthermore, it would also be important to assess whether preparation for consumption or cooking affects the iodine content of algae. Algae consumption may also have beneficial health effects. Scientific literature has shown that it is a good source of fiber and vitamins, especially vitamin B{sub 12}.

Phaneuf, D.; Cote, I.; Dumas, P.; Ferron, L.A.; LeBlanc, A. [CHUQ, Sainte-Foy, Quebec (Canada). Centre de Toxicologie du Quebec] [CHUQ, Sainte-Foy, Quebec (Canada). Centre de Toxicologie du Quebec

1999-02-01

50

A Study of the St. Lawrence River Ecological Habitat  

ERIC Educational Resources Information Center

Save the River, a grassroots advocacy group established in 1978, lobbies for policies to preserve the upper St. Lawrence River and uses the community's help to keep an eye on the existing habitats. Recently, they procured the Fresh Sound Foundation grant to support the development of new K-12 ecology curricula by local area teachers to educate…

Mesires, Maria

2010-01-01

51

Spending Time and Money: Memories of Life in St. Lawrences  

ERIC Educational Resources Information Center

Mabel Cooper and Gloria Ferris spent their early adult life in St. Lawrence's Hospital in Caterham. This was in the late 1950s to early 1970s. This is their memories of how they spent their time. It includes the work they did and leisure. They also write about the tokens that were used in the hospital instead of money.

Abraham, Jane; Cooper, Mabel; Ferris, Gloria

2010-01-01

52

Groundwater quality in the Delaware and St. Lawrence River Basins, New York, 2010  

USGS Publications Warehouse

Water quality in both study areas is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards. The standards exceeded are color (one sample in the St. Lawrence study area), pH (three samples in the Delaware study area), sodium (one sample in the St. Lawrence study area), total dissolved solids (one sample in the St. Lawrence study area), aluminum (one sample in the Delaware study area and one sample in the St. Lawrence study area), iron (seven samples in the St. Lawrence study area), manganese (one sample in the Delaware study area and five samples in the St. Lawrence study area), gross alpha radioactivity (one sample in the St. Lawrence study area), radon-222 (10 samples in the Delaware study area and 14 samples in the St. Lawrence study area), and bacteria (

Nystrom, Elizabeth A.

2012-01-01

53

Paleoceanography and glacial runoff along the St. Lawrence valley system  

SciTech Connect

Radiocarbon-dated foraminiferal zones in cores from the Gulf of St. Lawrence show that cold saline bottom-water was present in the Goldthwait Sea between 13.6 and 12.9 ka BP and was followed by a salinity minimum from ca. 12.1 to 8.6 ka BP, and then increasing salinity and temperature resulting in the modern, deep, watermass layer by 8 ka BP. During the salinity minimum, glacial Lake St. Lawrence drained east into the Goldthwait Sea before the beginning of the Champlain Sea (11.6--11.4 ka BP). Meltwater flowed through the Champlain and Goldthwait seas between 11 and 10 ka BP when Lake Agassiz water was diverted to the North Atlantic Ocean through Ottawa and St. Lawrence valleys and Gulf of St. Lawrence; this coincides with the decrease in salinity of the Champlain Sea between 10.7 and 10.4 ka BP. A later discharge of meltwater to the North Atlantic Ocean (9.5--8 ka BP) occurred during the final stage of the salinity minimum in the Goldthwait Sea and postdates or coincides with the end of the Champlain Sea. The discharge of meltwater to the North Atlantic Ocean may have cause the freshening of the Champlain Sea. However, it does not appear to have affected the deep water in the Goldthwait Sea and was probably part of the surface outflow to the North Atlantic Ocean through the Gulf of St. Lawrence. The variations in salinity of the deep water of the Goldthwait Sea are related to changes in the composition of the water entering the sea from the North Atlantic Ocean.

Rodrigues, C.G. (Univ. of Windsor, Windsor, Ontario (Canada). Dept. of Geology); Vilks, G. (Bedford Inst. of Oceanography, Dartmouth, NS (United States))

1992-01-01

54

Influence of St. Lawrence River discharge on the circulation and hydrography in Canadian Atlantic waters  

NASA Astrophysics Data System (ADS)

This study examines the effects of freshwater discharge from the St. Lawrence River (SLR) on the three-dimensional circulation and hydrography in Canada's Atlantic waters using a regional shelf circulation model based on the Princeton Ocean Model. The study region comprises the Gulf of St. Lawrence, the Scotian Shelf, and the Gulf of Maine. The model forcing includes atmospheric forcing at the sea surface; tidal elevation and currents at the lateral open boundaries; and freshwater discharge from the SLR and other major rivers in the region. The forcing at the lateral open boundaries also includes non-tidal currents as well as temperature and salinity fields produced by a coarse-resolution circulation model for the northwest Atlantic. The shelf circulation model is integrated for 5 years (1999-2003); the simulated hydrography and circulation during the last 4 years are compared to observations to assess the model's performance. Three additional model runs are made, called the climate, wet, and dry runs, in which the SLR discharge values specified in the model are respectively the long-term mean and the long-term mean plus or minus 3.5 standard deviations. Model results from the climate run demonstrate that the variability of freshwater flux in the St. Lawrence Estuary takes ˜100 days to reach Cabot Strait; ˜160 days to reach the central Scotian Shelf; and ˜220 days to reach the eastern Gulf of Maine. Within the Gulf of St. Lawrence, an increase in the SLR discharge results in a stronger Gaspé Current (up to ˜0.1 m s-1 stronger in the wet run than in the dry run) as well as lower salinity in the western part of the gulf. In the winter, the effect of a higher SLR discharge extends along the Scotian Shelf and into the Gulf of Maine, with salinity in both areas lower by ˜0.1 psu in the wet run than in the dry run.

Ohashi, Kyoko; Sheng, Jinyu

2013-04-01

55

Supracrustal faults of the St. Lawrence rift system, Québec: kinematics and geometry as revealed by field mapping and marine seismic reflection data  

NASA Astrophysics Data System (ADS)

The St. Lawrence rift system from the Laurentian craton core to the offshore St. Lawrence River system is a seismically active zone in which fault reactivation is believed to occur along late Proterozoic to early Paleozoic normal faults related to the opening of the Iapetus ocean. The rift-related faults fringe the contact between the Grenvillian basement to the NW and Cambrian-Ordovician rocks of the St. Lawrence Lowlands to the SE and occur also within the Grenvillian basement. The St. Lawrence rift system trends NE-SW and represents a SE-dipping half-graben that links the NW-SE-trending Ottawa-Bonnechère and Saguenay River grabens, both interpreted as Iapetan failed arms. Coastal sections of the St. Lawrence River that expose fault rocks related to the St. Lawrence rift system have been studied between Québec city and the Saguenay River. Brittle faults marking the St. Lawrence rift system consist of NE- and NW-trending structures that show mutual crosscutting relationships. Fault rocks consist of fault breccias, cataclasites and pseudotachylytes. Field relationships suggest that the various types of fault rocks are associated with the same tectonic event. High-resolution marine seismic reflection data acquired in the St. Lawrence River estuary, between Rimouski, the Saguenay River and Forestville, identify submarine topographic relief attributed to the St. Lawrence rift system. Northeast-trending seismic reflection profiles show a basement geometry that agrees with onshore structural features. Northwest-trending seismic profiles suggest that normal faults fringing the St. Lawrence River are associated with a major topographic depression in the estuary, the Laurentian Channel trough, with up to 700 m of basement relief. A two-way travel-time to bedrock map, based on seismic data from the St. Lawrence estuary, and comparison with the onshore rift segment suggest that the Laurentian Channel trough varies from a half-graben to a graben structure from SW to NE. It is speculated that natural gas occurrences within both the onshore and offshore sequences of unconsolidated Quaternary deposits are possibly related to degassing processes of basement rocks, and that hydrocarbons were drained upward by the rift faults.

Tremblay, Alain; Long, Bernard; Massé, Manon

2003-07-01

56

Knowing, mapping and understanding St. Lawrence biodiversity, with special emphasis on bird assemblages.  

PubMed

Environment Canada and the Québec Department of the Environment, partners in the St Lawrence Vision 2000 Action Plan, set out to prepare a compendium of knowledge of the flora and fauna of the St Lawrence and to identify potential conservation sites. The resulting Portrait is an Internet site that presents the current knowledge base of the river's ecological and biological diversity (http://lavoieverte.qc.ec.gc.ca/faune/biodiv/index.html). The Portrait provides information on over 5,000 species of flora and fauna. On the website, you will find a detailed ecological analysis of the richness, rarity and vulnerability of several broad groups of plant and animal species. Furthermore, you will find a list of species for each of the 700 survey units and a distribution map for 2,500 species recorded along the St Lawrence., in atlas form, along with a detailed conservation plan. The plan encompasses the most unique and heterogeneous landscapes of the St Lawrence, some of which have no protection at present. The Portrait provides an overview of the sites that are currently protected by public agencies and private-sector organisations and identifies new sites of interest for conserving biodiversity and protecting species at risk. This paper exposes the content of this extensive compendium on the biodiversity of the St. Lawrence. For conciseness, it presents some of the analyses conducted on birds to illustrate a few of the analytical approaches that were used. Then, the information on species richness and concentration areas for priority species of vascular plants, breeding birds and herpetofauna will serve to identify the terrestrial sites of significance for biodiversity. Finally, a similar approach having been applied to the aquatic environnement, we will conclude with a conservation plan that identifies the terrestrial and aquatic ecosystems, and the geographic sites where the most important elements of St. Lawrence biodiversity are concentrated. Our analysis of the biodiversity of the most thoroughly studied taxa of the St. Lawrence clearly shows the importance of wetlands, particularly those located at the mouths of rivers or within archipelagos or delta complexes, such as the groups of islands and channels found at both ends of the Montreal Archipelago. These aquatic landscapes are sites of intense biological production, combining in a small geographical area spawning, nursery and feeding grounds for a large number of fish species and breeding, rearing and foraging areas for aquatic birds. Variable flooding conditions, associated with seasonal flooding or daily tidal fluctuations, create a complex mosaic of wetland and aquatic habitats. Although wetlands occupy only a small area in comparison with terrestrial habitats, they support a large number of rare plant and animal species in relation to their size. At present, 10% of the vascular flora and 27% of the herpetofauna of the St. Lawrence are at risk. In the case of reptiles and amphibians, the situation is especially worrisome because nearly all of the most threatened species live in a narrow band along the river corridor. Not only is this the sector that is under the greatest pressure from human development, very little public land remains here, making it difficult to create protected areas. Increased participation by non-governmental organisations and individuals, through private stewardship arrangements, is an essential precondition for completing the network of conservation areas in this part of the St. Lawrence. Along the estuary and the Gulf, habitat integrity has not been affected as much by the expansion of Québec's human population. This is a vast territory, and sites have been identified with a view to making up for the deficiencies in the present network of protected sites in terms of representing biodiversity. PMID:14570415

Desgranges, Jean-Luc; Jobin, Benoît

2003-01-01

57

Relationships between metallothionein induction, cadmium, copper and zinc levels and environmental parameters in the soft shell clam Mya arenaria in the Saguenay fjord and the St. Lawrence River maritime estuary  

Microsoft Academic Search

Physiological status of Mya arenaria is threatened in the Saguenay-Saint Lawrence system due to inputs of many kinds of pollutants from anthropogenic and industrial origins. Investigations of the health of M. arenaria were carried out using metallothioneins concentrations as biomarkers of metallic contamination in relation with concentrations of metals.

Jocelyne Pellerin; Jean-Claude Amiard

2008-01-01

58

Benthic nutrient fluxes along the Laurentian Channel: Impacts on the N budget of the St. Lawrence marine system  

NASA Astrophysics Data System (ADS)

Water column concentrations and benthic fluxes of dissolved inorganic nitrogen (DIN) and oxygen (DO) were measured in the Gulf of St. Lawrence and the Upper and Lower St. Lawrence Estuary (USLE and LSLE, respectively) to assess the nitrogen (N) budget in the St. Lawrence (SL) system, as well as to elucidate the impact of bottom water hypoxia on fixed-N removal in the LSLE. A severe nitrate deficit, with respect to ambient phosphate concentrations (N*˜-10 ?mol L -1), was observed within and in the vicinity of the hypoxic bottom water of the LSLE. Given that DO concentrations in the water column have remained above 50 ?mol L -1, nitrate reduction in suboxic sediments, rather than in the water column, is most likely responsible for the removal of fixed N from the SL system. Net nitrate fluxes into the sediments, derived from pore water nitrate concentration gradients, ranged from 190 ?mol m -2 d -1 in the hypoxic western LSLE to 100 ?mol m -2 d -1 in the Gulf. The average total benthic nitrate reduction rate for the Laurentian Channel (LC) is on the order of 690 ?mol m -2 d -1, with coupled nitrification-nitrate reduction accounting for more than 70%. Using average nitrate reduction rates derived from the observed water column nitrate deficit, the annual fixed-N elimination within the three main channels of the Gulf of St. Lawrence and LSLE was estimated at 411 × 10 6 t N, yielding an almost balanced N budget for the SL marine system.

Thibodeau, Benoît; Lehmann, Moritz F.; Kowarzyk, Jacqueline; Mucci, Alfonso; Gélinas, Yves; Gilbert, Denis; Maranger, Roxane; Alkhatib, Mohammad

2010-12-01

59

Sources and fluxes of mercury in the St. Lawrence River  

SciTech Connect

A mass balance approach, based essentially on the reconstruction of daily fluxes and circumscribed by strict error calculations, was designed to quantify the main mercury sources for the St. Lawrence and its tributaries, which constitute a large river system. High-frequency samplings were performed over an 18-month period (1955--1996) at the main water inputs and the mouth of the river. Minor tributaries and the Montreal effluent were also sampled. This strategy allowed models to be obtained that relate mercury concentrations in solution and in particles to the hydrological regime. The calculated budget was balanced relative to the calculated errors of the estimates. Gross mercury export from the river was found to be 5.9 kmol yr{sup {minus}1}. Tributaries and internal erosion of the river contributed equally for a total of 75% of this gross load, whereas the Upper St. Lawrence River, which is almost exclusively composed of Lake Ontario waters, accounted for less than 10%, and inventoried anthropogenic point sources accounted for about 5%. Dissolved mercury was mainly from north shore tributaries, and particulate mercury was largely from erosion of the river bed and banks. On the basis of the present results as well as estimates of atmospheric deposition from the literature it can be inferred that at least 88% of deposited mercury was retained in the watersheds.

Quemerais, B.; Rondeau, B.; Pham, T.T.; Gagnon, P.; Fortin, B. [Environment Canada, Montreal, Quebec (Canada). St. Lawrence Centre] [Environment Canada, Montreal, Quebec (Canada). St. Lawrence Centre; Cossa, D. [Inst. Francais de Recherche pour l`Exploitation de la Mer, Nantes (France)] [Inst. Francais de Recherche pour l`Exploitation de la Mer, Nantes (France)

1999-03-15

60

Author's personal copy Fossil brines preserved in the St-Lawrence Lowlands,  

E-print Network

Author's personal copy Fossil brines preserved in the St-Lawrence Lowlands, Que´bec, Canada and Ordovician dolostones of the St-Lawrence Lowlands at Be´cancour, Que´bec, Canada were sampled for analysis, penetrating into or below the deeper Cambrian­Ordovician aquifers. Dur- ing the Devonian, the basin reached

Long, Bernard

61

Organochlorine and Metal Contaminants in Traditional Foods from St. Lawrence Island, Alaska  

Microsoft Academic Search

Marine mammals (bowhead whale, walrus, and various seals) constitute the major component of the diet of the Yupik people of St. Lawrence Island, Alaska. St. Lawrence Island residents have higher serum concentrations of polychlorinated biphenyls (PCB) than in the general U.S. population. In order to determine potential sources, traditional food samples were collected from 2004 to 2009 and analyzed for

Gretchen Welfinger-Smith; Judith L. Minholz; Sam Byrne; Vi Waghiyi; Jesse Gologergen; Jane Kava; Morgan Apatiki; Eddie Ungott; Pamela K. Miller; John G. Arnason; David O. Carpenter

2011-01-01

62

Pristine Lake Saint-François, St. Lawrence River: Hydrodynamic Simulation and Cumulative Impact  

Microsoft Academic Search

Lake Saint-François is a fluvial lake of the St. Lawrence system which is used for hydropower production and commercial navigation. For 150 years, it was dredged and dammed regularly without any impact analysis being made. The cumulative impact of dredging and damming on large rivers such as the St. Lawrence is an issue with only qualitative answers. Bidimensional hydrodynamics was

Jean Morin; Paul Boudreau; Yves Secretan; Michel Leclerc

2000-01-01

63

Bioassessment of Benthic Macroinvertebrates in Wetland Habitats of Lake Saint-Pierre (St. Lawrence River)  

Microsoft Academic Search

We evaluated the potential of vegetation and sediment habitats in wetlands of the St. Lawrence River for developing a macroinvertebrate bioassessment program with reference conditions. During September 2004, we collected macroinvertebrates in emergent vegetation and sediment in both fluvial sites (reference) and tributary-plume sites (impacted) in waters of the north and south shores of Lake Saint-Pierre (St. Lawrence River). In

Laure Tall; Ginette Méthot; Alain Armellin; Bernadette Pinel-Alloul

2008-01-01

64

NOAA Technical Memorandum ERL GLERL-104 GREAT LAKES AND ST. LAWRENCE RIVER MEDIUM RESOLUTION VECTOR  

E-print Network

NOAA Technical Memorandum ERL GLERL-104 GREAT LAKES AND ST. LAWRENCE RIVER MEDIUM RESOLUTION VECTOR SHORELINE DATA D.H. LEE NOAA, Great Lakes Environmental Research Laboratory, Ann Arbor, MI C. MORSE, and S ............................................................................................................................................. 4 2. Great Lakes-St. Lawrence River Vector Shoreline Data

65

The influence of wind and ice on spring walrus hunting success on St. Lawrence Island, Alaska  

E-print Network

The influence of wind and ice on spring walrus hunting success on St. Lawrence Island, Alaska Henry Available online 14 March 2013 Keywords: Pacific walrus (Odobenus rosmarus divergens) Hunting St. Lawrence divergens) each year. The harvest and associated effort (hunting trips taken), however, are variable from

Zhang, Jinlun

66

Three-dimensional modeling of hydrodynamic processes in the St. Lucie Estuary  

Microsoft Academic Search

Comparing with the studies on large estuarine systems, such as the Chesapeake Bay and the San Francisco Bay, the processes of stratification and transport in small and shallow estuaries are relatively less studied. The St. Lucie Estuary (SLE) is a riverine estuary located on the east coast of south Florida. It is small and shallow, with mean depth of 2.4m.

Zhen-Gang Ji; Guangdou Hu; Jian Shen; Yongshan Wan

2007-01-01

67

Wildlife as sentinels of human health effects in the Great Lakes--St. Lawrence basin.  

PubMed

There is no existing formal, long-term program for gathering evidence of the incidence and severity of the health effects of toxic substances in wildlife. However, research-based studies of bald eagles, herring gulls, night herons, tree swallows, snapping turtles, mink, and beluga over the past 30 years have revealed a broad spectrum of health effects in the Great Lakes-St. Lawrence basin including thyroid and other endocrine disorders, metabolic diseases, altered immune function, reproductive impairment, developmental toxicity, genotoxicity, and cancer. These effects occurred most often and were most severe in the most contaminated sites (Green Bay, Saginaw Bay, Lake Ontario, the St. Lawrence estuary, and more recently, Lake Erie), some of which are International Joint Commission-designated Areas of Concern (AOCs). In all cases, a strong argument can be made for an environmental etiology, and in many cases for the involvement of persistent organic pollutants, particularly polychlorinated biphenyls, polychlorinated dibenzo-(italic)p(/italic)-dioxins, and polycyclic aromatic hydrocarbons. For some, the association with particular contaminants is consistent with controlled studies, and in some, dose-response relationships were documented. The biologic significance of these health impairments to the affected species is currently unclear, but they resemble those observed with increased incidence in human subpopulations in one or more AOCs. Formalizing health effects monitoring of sentinel wildlife species by the parties to the Canada-USA Great Lakes Water Quality Agreement is required. This would facilitate the optimal use of sentinel wildlife health data in a larger, epidemiologic weight-of-evidence context upon which to base decisions and policies regarding the effects of chemical exposures on human populations. PMID:11744503

Fox, G A

2001-12-01

68

Wildlife as sentinels of human health effects in the Great Lakes--St. Lawrence basin.  

PubMed Central

There is no existing formal, long-term program for gathering evidence of the incidence and severity of the health effects of toxic substances in wildlife. However, research-based studies of bald eagles, herring gulls, night herons, tree swallows, snapping turtles, mink, and beluga over the past 30 years have revealed a broad spectrum of health effects in the Great Lakes-St. Lawrence basin including thyroid and other endocrine disorders, metabolic diseases, altered immune function, reproductive impairment, developmental toxicity, genotoxicity, and cancer. These effects occurred most often and were most severe in the most contaminated sites (Green Bay, Saginaw Bay, Lake Ontario, the St. Lawrence estuary, and more recently, Lake Erie), some of which are International Joint Commission-designated Areas of Concern (AOCs). In all cases, a strong argument can be made for an environmental etiology, and in many cases for the involvement of persistent organic pollutants, particularly polychlorinated biphenyls, polychlorinated dibenzo-(italic)p(/italic)-dioxins, and polycyclic aromatic hydrocarbons. For some, the association with particular contaminants is consistent with controlled studies, and in some, dose-response relationships were documented. The biologic significance of these health impairments to the affected species is currently unclear, but they resemble those observed with increased incidence in human subpopulations in one or more AOCs. Formalizing health effects monitoring of sentinel wildlife species by the parties to the Canada-USA Great Lakes Water Quality Agreement is required. This would facilitate the optimal use of sentinel wildlife health data in a larger, epidemiologic weight-of-evidence context upon which to base decisions and policies regarding the effects of chemical exposures on human populations. PMID:11744503

Fox, G A

2001-01-01

69

Characterization of St. Lawrence blue whale vocalizations and their correlation with field observations  

NASA Astrophysics Data System (ADS)

During four field seasons from 1998--2001, 115 hours of acoustic recordings were made in the presence of the well-studied St. Lawrence population of blue whales. The primary field site for this study was the estuary region of the St. Lawrence River (Quebec, Canada) with most recordings made between mid-August and late October. Effort was concentrated in the daylight hours, although occasionally extending past nightfall. An inexpensive and portable recording system was built that was easy to deploy and provided quality recordings in a variety of sea conditions. It consisted of a calibrated omni-directional hydrophone with a flat (+/-3dB) response from 5Hz to 800Hz; and a surface isolation buoy to minimize the vertical movement of the sensor. During the recording sessions detailed field notes were taken on all blue whales within sight, with individual identities confirmed through photo-identification work between sessions. Notes were also taken on all other species sighted during the recording sessions. Characterization of the more than one-thousand blue whale calls detected during this study revealed that the St. Lawrence repertoire is much more extensive than previously reported. Three infrasonic (<20Hz) and four audible range (30--200Hz) call types were detected in this study, with much time/frequency variation seen within each type. The infrasonic calls were long (5--30s) in duration and arranged into regularly patterned series. These calls were similar in call characteristics and spacing to those detected in the North Atlantic, but had much shorter and more variable patterned series. The audible call types were much shorter (1--4s), and occurred singly or in irregularly spaced clusters, although a special patterning was seen that contained both regular and irregular spaced components. Comparison of the daily, seasonal, and spatial distributions of calling behavior with those of several biological parameters revealed interesting differences between the three call types examined. The trends seen suggest a migratory, reproductive, or foraging context for the infrasonic calls. A closer-range social context is suggested for the audible downsweeps, which have been detected in foraging situations as well as in courtship displays. The audible mixed-pattern call type appears to have a primarily reproductive context.

Berchok, Catherine L.

70

Comparison of St. Lawrence blue whale vocalizations with field observations  

NASA Astrophysics Data System (ADS)

During four field seasons from 1998-2001, vocalizations were recorded in the presence of St. Lawrence blue whales using a single omni-directional hydrophone. Both long duration infrasonic calls (~18 Hz, 5-20 s) as well as short duration higher frequency calls (85-25 Hz, ~2 s) were detected and compared with field observations. Two trends were noted. First, the long infrasonic call series were concentrated primarily in the deep (300 m) channel. These call series appear to compare well with blue whale vocalizations recorded by others in the deep open ocean. Second, the shorter audible calls were more evenly distributed over bathymetry and seem to be a form of short distance communication with at least one case occurring during an agonistic interaction. A comparison of these calls with biological parameters such as density of whales in the area, percentages of paired versus single whales, and numbers of males versus females will also be discussed. [Project supported by ARL/PSU, NSF, and the American Museum of Natural History.

Berchok, Catherine; Bradley, David; Gabrielson, Thomas; Sears, Richard

2003-04-01

71

Modelling spatial distribution of epibenthic communities in the Gulf of St. Lawrence (Canada)  

NASA Astrophysics Data System (ADS)

Correlative habitat models using relationships between marine organisms and their surrounding environment can be used to predict species distribution, and the results can assist management of human activities sharing the marine space (e.g. fisheries, MPAs, tourism). Here, epi-benthic megafauna was sampled at 755 stations in the Lower Estuary and Northern Gulf of St. Lawrence (EGSL) each summer between 2006 and 2009. We combined various types of multivariate analyses to 1) describe the structure and spatial distribution of benthic communities, 2) analyse the relationship between these communities and environmental parameters, and subsequently 3) build a community distribution model to predict the spatial distribution of the communities, creating community distribution maps covering the entire area to be used for marine management and conservation. We identified distinct benthic communities in the study area that closely correlate with the 200 m depth contour and with major environmental variables. A redundancy analysis revealed that communities were associated with depth, oxygen saturation, temperature, bottom current, seabed uniformity, distance to coast and type of sediment. Together these environmental descriptors explained 38% of the variation in megafaunal community composition. The environmental variables were used to build a community distribution model using generalized linear models to predict high and low suitability zones of each community in the EGSL.

Moritz, Charlotte; Lévesque, Mélanie; Gravel, Dominique; Vaz, Sandrine; Archambault, Diane; Archambault, Philippe

2013-04-01

72

Field measurements of ship waves along the St. Lawrence river waterway, Canada  

Microsoft Academic Search

Coastal erosion along the St. Lawrence river waterway in Quebec, Canada, represents a hazard to local communities living along the river banks, as well as to the local fauna habitat. The purpose of this study is to assess the potential impact of longer containerships on riverbank erosion and recession at critical sites along the Saint Lawrence river waterway. A field

S. Gharbi; S. Hamdi; G. Valkov; I. Nistor

2008-01-01

73

Influence of Summer Water-Level Variability on St. Lawrence River-Wetland Fish Assemblages  

Microsoft Academic Search

Water-level and associated variability are substantial influences on wetland and shallow aquatic communities. The Akwesasne Wetland Complex is an extensive St. Lawrence River system affected by water regulation. The responses offish assemblages to short-term summer water-level variation were examined throughout this section of the St. Lawrence River and its tributaries. An influence of water-level variability was detected on abundance of

James E. McKenna Jr; Joyce L. Barkley; James H. Johnson

2008-01-01

74

Adapting to Climate Change and Variability in the Great Lakes-St. Lawrence Basin Great Lakes-St. Lawrence Basin Project  

E-print Network

Adapting to Climate Change and Variability in the Great Lakes-St. Lawrence Basin 52 Great Lakes; this is the adaptation component. Communication of climate change information to various publics, and adaptation strategies. The GLSLB Project had a number of goals. The impacts of climate variability and change

75

Automatic recognition of fin and blue whale calls for real-time monitoring in the St. Lawrence.  

PubMed

Monitoring blue and fin whales summering in the St. Lawrence Estuary with passive acoustics requires call recognition algorithms that can cope with the heavy shipping noise of the St. Lawrence Seaway and with multipath propagation characteristics that generate overlapping copies of the calls. In this paper, the performance of three time-frequency methods aiming at such automatic detection and classification is tested on more than 2000 calls and compared at several levels of signal-to-noise ratio using typical recordings collected in this area. For all methods, image processing techniques are used to reduce the noise in the spectrogram. The first approach consists in matching the spectrogram with binary time-frequency templates of the calls (coincidence of spectrograms). The second approach is based on the extraction of the frequency contours of the calls and their classification using dynamic time warping (DTW) and the vector quantization (VQ) algorithms. The coincidence of spectrograms was the fastest method and performed better for blue whale A and B calls. VQ detected more 20 Hz fin whale calls but with a higher false alarm rate. DTW and VQ outperformed for the more variable blue whale D calls. PMID:20000904

Mouy, Xavier; Bahoura, Mohammed; Simard, Yvan

2009-12-01

76

Time Series Analysis of Water Level and Temperature in the St Louis River Estuary  

EPA Science Inventory

Pressure and temperature loggers were deployed at 9 sites in the St Louis River estuary between 6/23 10/31 2011. A reference sensor was place on the shore to correct pressure data. Sensors were paced at ...

77

Influence of summer water-level variability on St. Lawrence River-wetland fish assemblages  

USGS Publications Warehouse

Water-level and associated variability are substantial influences on wetland and shallow aquatic communities. The Akwesasne Wetland Complex is an extensive St. Lawrence River system affected by water regulation. The responses of fish assemblages to short-term summer water-level variation were examined throughout this section of the St. Lawrence River and its tributaries. An influence of water-level variability was detected on abundance of three common species [bluntnose minnow (Pimephales notatus), rock bass (Amboplites rupestris), and white sucker (Catastomus commersonii)] and explained 30-44% of variation. This influence has implications for water regulation and natural resource management, and a larger scope evaluation may reveal more extensive effects.

McKenna, J.E., Jr.; Barkley, J.L.; Johnson, J.H.

2008-01-01

78

A threatened beluga (Delphinapterus leucas) population in the traffic lane: vessel-generated noise characteristics of the Saguenay-St. Lawrence Marine Park, Canada.  

PubMed

The threatened resident beluga population of the St. Lawrence Estuary shares the Saguenay-St. Lawrence Marine Park with significant anthropogenic noise sources, including marine commercial traffic and a well-established, vessel-based whale-watching industry. Frequency-dependent (FD) weighting was used to approximate beluga hearing sensitivity to determine how noise exposure varied in time and space at six sites of high beluga summer residency. The relative contribution of each source to acoustic habitat degradation was estimated by measuring noise levels throughout the summer and noise signatures of typical vessel classes with respect to traffic volume and sound propagation characteristics. Rigid-hulled inflatable boats were the dominant noise source with respect to estimated beluga hearing sensitivity in the studied habitats due to their high occurrence and proximity, high correlation with site-specific FD-weighted sound levels, and the dominance of mid-frequencies (0.3-23 kHz) in their noise signatures. Median C-weighted sound pressure level (SPL(RMS)) had a range of 19 dB re 1 ?Pa between the noisiest and quietest sites. Broadband SPL(RMS) exceeded 120 dB re 1 ?Pa 8-32% of the time depending on the site. Impacts of these noise levels on St. Lawrence beluga will depend on exposure recurrence and individual responsiveness. PMID:22225023

McQuinn, Ian H; Lesage, Véronique; Carrier, Dominic; Larrivée, Geneviève; Samson, Yves; Chartrand, Sylvain; Michaud, Robert; Theriault, James

2011-12-01

79

Diel and lateral patterns of zooplankton distribution in the St. Lawrence River  

Microsoft Academic Search

While the four-dimensional nature of river ecosystems has been recognized for nearly two decades, the role of lateral complexity has rarely been factored into studies of zooplankton ecology. We examined the importance of hydrologic retention areas (slackwaters) near islands and embayments of the St. Lawrence River for densities, fecundity, and diel migration of planktonic microcrustaceans. Densities of cladocera and copepods

Andrew F. Casper; James H. Thorp

2007-01-01

80

DAMAGE ASSESSMENT STUDIES FOLLOWING THE NEPCO 140 OIL SPILL ON THE ST. LAWRENCE RIVER  

EPA Science Inventory

The primary objective of this two-and-one half year research effort was to determine the environmental and economic impacts of the NEPCO 140 oil spill. This spill occurred in the freshwater environment of the St. Lawrence River on June 23, 1976. The cleanup operation, which cost ...

81

BIOREMEDIATION AND BIORESTORATION OF A CRUDE OIL CONTAMINATED FRESHWATER WETLAND ON THE ST. LAWRENCE RIVER  

EPA Science Inventory

Biostimulation by nutrient enrichment and phytoremediation were studied for the restoration of an acutely stressed freshwater wetland experimentally exposed to crude oil. The research was carried out along the shores of the St. Lawrence River at Ste. Croix, Quebec, Canada. The ...

82

POTASSIC MAGMATISM ON ST. LAWRENCE ISLAND, ALASKA, AND CAPE DEZHNEV, NORTHEAST RUSSIA  

E-print Network

rocks, Permian(?) to Triassic gabbroic rocks, Cretaceous plutonic and volcanic rocks, and Quaternary volcanic and plutonic rocks on St. Lawrence Island, as well as geochemical and geo-chronologic data from this pluton yields an age of 102 ± 0.5 Ma. The subalkaline plutonic and volcanic rocks are comagmatic

Toro, Jaime

83

POTASSIC MAGMATISM ON ST. LAWRENCE ISLAND, ALASKA, AND CAPE DEZHNEV, NORTHEAST RUSSIA  

E-print Network

rocks, Permian(?) to Triassic gabbroic rocks, Cretaceous plutonic and volcanic rocks, and Quaternary volcanic and plutonic rocks on St. Lawrence Island, as well as geochemical and geochronologic data from this pluton yields an age of 102 ± 0.5 Ma. The subalkaline plutonic and volcanic rocks are comagmatic

Amato, Jeff

84

Community interactions affecting the relative abundances of native and invasive amphipods in the St. Lawrence River  

Microsoft Academic Search

The Eurasian amphipod Echinogammarus ischnus is reportedly replacing the common native amphipod Gammarus fasciatus in the Great Lakes - St. Lawrence River system. A potential mechanism for this replacement is competition mediated by resident species. Other Eurasian invaders, dreissenid mussels (Dreissena polymorpha and Dreissena bugensis), dominate rocky substrates throughout the system and might be promoting the rapid expansion of E.

M. E. Palmer; Anthony Ricciardi

2005-01-01

85

Office of the Chief Financial Officer | Lawrence Berkeley National Laboratory 6401 Hollis St.  

E-print Network

Office of the Chief Financial Officer | Lawrence Berkeley National Laboratory 6401 Hollis St East (towards Sacramento/Berkeley). Take the Ashby Ave. and Shellmound exit (first exit). Stay Highway 880 North (towards Oakland). Connect to 80 East (towards Sacramento/Berkeley). Take the Ashby Ave

Eisen, Michael

86

Binational GIS database of coastal wetlands for Lake Ontario and the St. Lawrence: a demonstration project  

E-print Network

Binational GIS database of coastal wetlands for Lake Ontario and the St. Lawrence: a demonstration In this project, I assembled a seamless binational GIS database that contains all available shapefiles of coastal (Wetland Inventory for Research and Education) website (http://www.wirenet.info). GIS was used to quantify

McMaster University

87

A Practical Grammar of the St. Lawrence Island/Siberian Yupik Eskimo Language. Second Edition.  

ERIC Educational Resources Information Center

This book deals with the Central Siberian Yupik Eskimo language as spoken on St. Lawrence Island, Alaska, an island near the Bering Strait and on the tip of the Asian mainland opposite Russia. This book has been used with college-level classes composed of a mixture of Yupik speakers and well-prepared non-speakers (people who have studied other,…

Jacobson, Steven A.

88

St. Lawrence River ecosystem monitoring: Selection of bioindicators and biomarkers of contamination and health  

SciTech Connect

The St. Lawrence River is contaminated by a large quantity of toxic substances from many sources, This contamination comes from the Great Lakes, as well as from industrial, urban and agricultural sources along its shores. The St. Lawrence Action Plan has, among other objectives, the goals of reducing the toxic inputs and the development of a surveillance network of the condition of the river. This network will include the selection of indicator species to follow the contamination of the trophic web to evaluate the success of the cleanup. It will also integrate ecotoxicological and demographic information to measure the effects of these toxic substances on living organisms and to follow the health of the system, in an ecosystemic approach. A number of species have been preselected on the basis of different ecological and physiological criteria. The Great Blue Heron and the Blackcrowned Night Heron, among other species, have been evaluated as indicator species for this network. Eggs and fledglings have been collected for contaminant and biochemical analysis from 1991 through 1994. Demographic data have also been collected. The data are compared between the two species, between St. Lawrence River colonies and to control colonies, as well as with data from the literature. In general, contamination levels are below those found in other regions and no effects on populations have been observed. However, preliminary results suggest that some of the biomarkers tested may be sensitive early indicators of wildlife contamination and health in the St. Lawrence River.

Champoux, L.; DesGranges, J.L.; Rodrigue, J. [Canadian Wildlife Service, Ste-Foy, Quebec (Canada); Trudeau, S. [Canadian Wildlife Service, Hull, Quebec (Canada); Hontela, A.; Boily, M.; Spear, P.A. [Univ. du Quebec, Montreal, Quebec (Canada)

1995-12-31

89

Genotoxic substances in the St. Lawrence system. 1: Industrial genotoxins sorbed to particulate matter in the St. Lawrence, St. Maurice, and Saguenay rivers, Canada  

SciTech Connect

Previous investigations of organic genotoxins in industrial effluents discharged into the St. Lawrence River system (Quebec, Canada) indicated that a substantial fraction of the genotoxicity is adsorbed to suspended particulate matter. This study used the SOS Chromotest to investigate the presence, potency, and behavior of particle-bound genotoxins in the downstream ecosystem. The results indicate that although extracts of both suspended and sedimented particulate matter are genotoxic, suspended particulate matter samples are more potent in the absence of S9 activation, with the reverse being true for bottom sediments. The results confirmed a positive relationship between the genotoxicity of bottom sediment extracts and sediment organic matter content. A similar relationship between organic matter content and total polycyclic aromatic hydrocarbon (PAH) concentration indicates that putative genotoxins have physicochemical properties similar to the PAH class of contaminants. Conversion of PAH values to benzo[a]pyrene equivalents indicates that measured PAHs only account for a small fraction ({approximately}10%) of the observed SOS Chromotest response. Sites that receive discharges from foundries, aluminum refineries, and petroleum refineries yielded several of the most genotoxic samples. Further analyses revealed that the genotoxicity of suspended and sedimented particulate matter extracts is empirically related to the genotoxicity of industrial discharges. Comparisons of total genotoxicity levels in suspended particulates and bottom sediments suggest that direct-acting substances adsorbed to suspended matter are rapidly degraded and/or converted to more stable progenotoxins upon deposition. Further research is required to test this hypothesis and investigate effects on indigenous biota.

White, P.A.; Rasmussen, J.B. [McGill Univ., Montreal, Quebec (Canada); Blaise, C. [Environment Canada, Montreal, Quebec (Canada). St. Lawrence Center

1998-02-01

90

Metals, trace elements, polychlorinated biphenyls, organochlorine pesticides, and brominated flame retardants in tissues of Barrow's goldeneyes (Bucephala islandica) wintering in the St. Lawrence marine ecosystem, eastern Canada.  

PubMed

The eastern North American population of Barrow's goldeneyes winters in the St. Lawrence Estuary and Gulf of St. Lawrence where the sediments and food web are known to be contaminated with inorganic and organic compounds. Therefore, there is a potential for contamination of this population, which is designated of Special Concern by the Committee on the Status of Endangered Wildlife in Canada. Specimens were collected during three consecutive winters (2005-2007) in three regions (Manicouagan, Charlevoix, and Chaleur Bay) and analysed for metals, trace elements, polychlorinated biphenyls (PCBs), organochlorine pesticides, and brominated flame retardants (BFRs). Liver mercury levels were greater in the St. Lawrence Estuary (4.4 mg/kg in Manicouagan, 3.8 mg/kg in Charlevoix) than in Chaleur (2.4 mg/kg), whereas selenium showed the opposite pattern (7.3 mg/kg in Manicouagan, 7.0 mg/kg in Charlevoix, and 36.9 mg/kg in Chaleur). Liver PCB levels were greater in specimens from Manicouagan (236 ng/g) than in those from the two other regions (72 ng/g in Charlevoix, 35 ng/g in Chaleur). DDT was greater in Chaleur (66 ng/g) versus 10 ng/g in Manicouagan and 16 ng/g in Charlevoix. BFRs were not compared among regions because of smaller sample sizes, but mean total concentration was low (4.02 ng/g). Overall, although significant differences were found across regions, levels of all contaminants measured are generally low and not of toxicological concern for this population. PMID:22875100

Ouellet, Jean-François; Champoux, Louise; Robert, Michel

2012-10-01

91

Sensitivity of tributaries to water-level fluctuations along the St-Lawrence corridor, Québec, Canada  

NASA Astrophysics Data System (ADS)

During the course of the last century, variations in the St-Lawrence water levels, caused by different uses of the river and the Great Lakes, have already had major impacts on riparian habitats and on a number of tributaries. Anticipated changes caused by climate change will only accentuate these impacts. At present, climate change scenarios forecast a decrease of the St-Lawrence water discharge by 20% over the next fifty years, which would correspond to a drop in water level between 0.5 and 1 metre at Montréal. Because the St- Lawrence corridor is in a region of lowlands, such fluctuations in water levels are expected to cause major adjustments in the morphology and longitudinal profiles of the tributaries through the erosion and incision of the river bed. These changes are important because ultimately, the sediment loads delivered to the St-Lawrence river are linked to the erosion processes occurring along its tributaries. However, given the important physical diversity of the tributaries, their sensitivity will differ, making it difficult to predict their individual response to environmental changes, especially given the paucity of data on the present state of the tributaries. Thus, our goal was to obtain data on the variability in morphosedimentology and dynamics of the tributaries in order to infer their sensitivity to fluctuations in baselevels. Bathymetric, hydraulic, and sedimentological surveys were conducted in 2004 and 2005 on five tributaries of the St-Lawrence: the Yamachiche, the St-Maurice, and the Batiscan rivers on the north shore, and the Richelieu and St-François rivers on the south shore. These tributaries cover a wide range of sizes and sedimentological characteristics, from cohesive clays to silts and gravel. Their hydrological regimes are also varied and are in some cases regulated, limiting the sediment capacity of certain tributaries. For example, the Yamachiche and St-François rivers have been under intense agricultural pressure, have fine sediments and have migrated significantly over the last fifty years, highlighting their instability and suggesting that changes in water levels may accentuate these erosion processes. On the other hand, the St-Maurice is highly regulated, has greater bank stability, due to its coarser sediment and intact riparian vegetation, and has remained fairly unmoved. This suggests that this river will respond more slowly to fluctuations in water levels. Investigating the current physical conditions of the tributaries will allow a better understanding of the long-term impacts of sustained periods of low water levels due to environmental change, and will help us develop a sensitivity index of the response of these rivers.

Charron, I.; Roy, A.; Boyer, C.; Verhaar, P.; Biron, P.; Morin, J.

2006-05-01

92

Annual Records of Toxic phytoplankton and PSP toxins in the Gulf of St. Lawrence, Quebec.  

NSDL National Science Digital Library

This website provides access to annual records of the abundance of phytoplankton species and physical-chemical parameters of seawater at monitoring stations in the Gulf of St. Lawrence, Quebec, Canada. Users may choose a particular station and the year to view the data (which are presented in MS-Excel format, in French). The webpage also provides a link to a map displaying the locations of the sampling stations.

2010-07-06

93

Year-Class Formation of Upper St. Lawrence River Northern Pike  

Microsoft Academic Search

Variables associated with year-class formation in upper St. Lawrence River northern pike Esox lucius were examined to explore population trends. A partial least-squares (PLS) regression model (PLS 1) was used to relate a year-class strength index (YCSI; 1974–1997) to explanatory variables associated with spawning and nursery areas (seasonal water level and temperature and their variability, number of ice days, and

Brian M. Smith; John M. Farrell; H. Brian Underwood; Stephen J. Smith

2007-01-01

94

Ocean response to attenuation of visible light by phytoplankton in the Gulf of St. Lawrence  

Microsoft Academic Search

The presence of phytoplankton affects the attenuation of the visible range of solar radiation in the upper ocean. An optically-coupled circulation model is used to examine the impact of phytoplankton on sea-surface temperature, stratification, circulation and air–sea non-solar heat fluxes in the Gulf of St. Lawrence. The attenuation coefficients are calculated by a spectral model of irradiance in the visible

Li Zhai; Charles Tang; Trevor Platt; Shubha Sathyendranath

2011-01-01

95

Budget and sources of suspended sediment transported in the St. Lawrence River, Canada  

Microsoft Academic Search

A mass balance budget of the suspended sediment in the St. Lawrence River was established for the sector stretching from Cornwall, Ontario, to Quebec City, Quebec, for the period 1989-1993. The approach consisted of analysing the amount of sediment contributed by the different tributaries, on a watershed-by-watershed basis, through sediment concentration-discharge models incorporating more than 4000 data points collected since

Bernard Rondeau; D. Cossa; P. Gagnon; L. Bilodeau

2000-01-01

96

Impact of the( Dreissena ) invasion on native unionid bivalves in the upper St. Lawrence River  

Microsoft Academic Search

Introduced Eurasian mussels (Dreissena polymorpha and Dreissena bugensis) colonized native unionid bivalves in the upper St. Lawrence River in the early 1990s. From 1992 to 1995, we examined the infestation and impact of Dreissena on unionids at several sites near the Island of MontrØal. Unionids suffered heavy (90ñ100%) mortality at sites where Dreissena occurred in high densities (i.e., 4000 ñ

A. Ricciardi; F. G. Whoriskey; J. B. Rasmussen

1996-01-01

97

Temporal changes in wetland landscapes of a section of the St. Lawrence River, Canada  

Microsoft Academic Search

Historical aerial photographs (from 1946 through 1983) were used to study and describe the nature and extent of changes in\\u000a wetland vegetation of a section of the St. Lawrence River and to evaluate the relative importance of water level, fire, and\\u000a vegetational development as causal factors of these historical changes. Data were encoded and analyzed using a geographical\\u000a information system,

Martin Jean; André Bouchard

1991-01-01

98

Feeding Ecology of Juvenile Lake Sturgeon in the St. Lawrence River System  

Microsoft Academic Search

We examined the diet of juvenile lake sturgeon Acipenser fulvescens at five sites in the St. Lawrence River, including two sites in major tributaries (Des Prairies and L'Assomption rivers), two main-stem sites located upstream (Verchères and Sorel-Berthier islands), and one site located downstream in the estuarine transition zone (ETZ). The benthic fauna was sampled at all sites except in the

Pedro Nilo; Serge Tremblay; Aline Bolon; Julian Dodson; Pierre Dumont; Réjean Fortin

2006-01-01

99

Contaminant Exposure and Biomarker Responses in Spectacled Eiders ( Somateria fischeri ) from St. Lawrence Island, Alaska  

Microsoft Academic Search

.   Effects of chemical contaminant exposure may be contributing to the decline of spectacled eiders (Somateria fischeri) nesting in coastal areas of western Alaska. We evaluated chemical exposure and potential effects in 20 male eiders collected\\u000a near St. Lawrence Island, Alaska. Analytes included metals, trace elements, chlorinated organics, and\\u000a 137Cesium (137Cs). Effects of contaminant exposure were evaluated using histopathology and

K. A. Trust; K. T. Rummel; A. M. Scheuhammer; I. L. Brisbin Jr.; M. J. Hooper

2000-01-01

100

Budget and sources of suspended sediment transported in the St. Lawrence River, Canada  

NASA Astrophysics Data System (ADS)

A mass balance budget of the suspended sediment in the St. Lawrence River was established for the sector stretching from Cornwall, Ontario, to Quebec City, Quebec, for the period 1989-1993. The approach consisted of analysing the amount of sediment contributed by the different tributaries, on a watershed-by-watershed basis, through sediment concentration-discharge models incorporating more than 4000 data points collected since 1983. Lake Ontario contributes less than 3% of the particulate load at Quebec City, while St. Lawrence tributaries on the south and north shores contribute 19% and 13%, respectively, of the sediment load. Our findings indicate that nearly 65% of the suspended sediments come from erosion of the bed and banks of the St. Lawrence River. This finding is broadly supported by numerous geomorphological and sedimentological observations and is consistent with the geological history of the river and the structures built on its banks in recent decades. Upstream-downstream mass balance studies conducted on individual river sectors indicate that the sources of erosion are located mainly in the Beauharnois Canal region, between Montreal and Les Grèves, and further downstream, between the outlet of Lake Saint-Pierre and Portneuf.

Rondeau, Bernard; Cossa, D.; Gagnon, P.; Bilodeau, L.

2000-01-01

101

Glacial Lake Outflow via the St. Lawrence Pathway Prior to the Champlain Sea Invasion and During the Younger Dryas  

NASA Astrophysics Data System (ADS)

When the Laurentide Ice Sheet receded north of the Adirondacks, Glacial Lake Frontenac overflowed to Glacial Lake Vermont (Coveville phase)-Albany. The water level of Lake Frontenac fell by about 90 m, as a result of the drawdown, glacio-isostatic rebound and outflow of Lake Vermont-Albany through the Hudson Valley to the North Atlantic Ocean. Lake level stabilized to form the Belleville, Upper Fort-Ann, post-Sherbrooke phase of glacial lakes post-Iroquois, Vermont and Memphremagog, respectively. Initially, the confluent fresh-water body extended from the Lake Ontario basin into the upper St. Lawrence Valley, Lake Champlain basin and along the Appalachian piedmont. The outlet of the lake was the Upper Fort-Ann sill, along the Hudson pathway (Lake Albany). The expansion of the lake was time transgressive and related to the regional ice retreat. As the lake expanded across the lowlands, into the Ottawa and central St. Lawrence valleys, and along the Appalachian piedmont, its level fell by about 20 m, from the Belleville to the Trenton strandlines on the western side of the Adirondacks, and about 26 m (Rayburn, 2004) from the Upper to the Lower Fort-Ann strandlines in the Lake Champlain basin. The extent of the lake during its final stage is estimated at about 30,000 km2. Varves deposited in the deeper parts of the lake are characterized by the ostracode Candona subtriangulata. Varve counts from several reference sections provide an approximate duration for the glaciolacustrine phase in different parts of the lowlands. They range from about 50 to 30 yr in the lower Ottawa Valley, where the estimated depth was 180 to 200 m, about 100 yr along the Appalachian piedmont and, tentatively, to more than 160 yr in the Lake Champlain basin (Rayburn et al., 2005). The lake overflowed/drained suddenly to the east, toward the western arm of the Goldthwait Sea, in the Estuary and Gulf of St. Lawrence, and hence into the North Atlantic Ocean. During this event, the water level fell by about 50 to 40 m to the highest strandline of the Champlain Sea. The timing and volume of this fresh-water discharge are quantified to allow assessment of its potential impact on the thermohaline circulation of the North Atlantic Ocean, and whether it could have triggered the cold Younger Dryas episode. The overflow occurred within a one-year span between 11.2 and 10.9 14C ka BP or 13.2 and 12.85 cal ka BP, close to the onset of the Younger Dryas cold interval. The total freshwater outflow through the St. Lawrence pathway comprised the one-year overflow phase (about 1500 km3), an early mixing phase of fresh and marine waters in the Champlain Sea domain (about 400 km3 for several years), a rapid collapse of the ice margin in the lowlands during about 250 yr and, during the Younger Dryas, several outburst floods from glacial Lake Algonquin into the Champlain Sea through the middle Ottawa Valley.

Occhietti, S.; Anderson, T. W.; Karrow, P. F.; Lewis, M. C.; Mott, R. J.; Parent, M.; Richard, P. J.; Rodrigues, C. G.; Stea, R.

2005-12-01

102

50 CFR Figure 17 to Part 679 - Northern Bering Sea Research Area and St. Lawrence Island Habitat Conservation Area  

Code of Federal Regulations, 2010 CFR

...Area and St. Lawrence Island Habitat Conservation Area 17 Figure 17 to part 679 Wildlife and Fisheries FISHERY CONSERVATION...THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Fig. 17 Figure 17 to part 679—Northern Bering Sea...

2010-10-01

103

78 FR 71037 - St. Lawrence & Atlantic Railroad Company-Discontinuance of Service Exemption-in Cumberland County...  

Federal Register 2010, 2011, 2012, 2013

...Service Exemption--in Cumberland County, Me. On November 8, 2013, St. Lawrence...74 near Deering, Cumberland County, Me., and milepost 25.97 at the town line...County and Auburn, Androscoggin County, Me. (the Line).\\1\\ The Line...

2013-11-27

104

46 CFR 401.405 - Basic rates and charges on the St. Lawrence River and Lake Ontario.  

Code of Federal Regulations, 2013 CFR

...Basic rates and charges on the St. Lawrence River and Lake Ontario. 401.405 Section 401.405 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE REGULATIONS Rates, Charges, and...

2013-10-01

105

46 CFR 401.405 - Basic rates and charges on the St. Lawrence River and Lake Ontario.  

Code of Federal Regulations, 2011 CFR

...Basic rates and charges on the St. Lawrence River and Lake Ontario. 401.405 Section 401.405 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE REGULATIONS Rates, Charges, and...

2011-10-01

106

46 CFR 401.405 - Basic rates and charges on the St. Lawrence River and Lake Ontario.  

Code of Federal Regulations, 2010 CFR

...Basic rates and charges on the St. Lawrence River and Lake Ontario. 401.405 Section 401.405 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE REGULATIONS Rates, Charges, and...

2010-10-01

107

46 CFR 401.405 - Basic rates and charges on the St. Lawrence River and Lake Ontario.  

Code of Federal Regulations, 2012 CFR

...Basic rates and charges on the St. Lawrence River and Lake Ontario. 401.405 Section 401.405 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE REGULATIONS Rates, Charges, and...

2012-10-01

108

Holocene Vegetation Dynamics of an Upper St. Lawrence River Wetland: Paleoecological Evidence for a Recent Increase in Cattail ( Typha )  

Microsoft Academic Search

Cattails (Typha latifolia L., Typha angustifolia L., and Typha x glauca Godr.) are the predominant emergent vegetation of upper St. Lawrence River coastal wetlands. We sought to describe Holocene\\u000a vegetation in a St. Lawrence River wetland to assess patterns of succession and examine the timing and potential causes of\\u000a a historic cattail invasion. Paleoecological analysis indicated presence of four distinct

Molly Beland Rippke; Matthew T. Distler; John M. Farrell

2010-01-01

109

Estuaries  

NSDL National Science Digital Library

Estuaries are bodies of water and their surrounding coastal wetlands typically found where rivers meet the sea. Estuaries harbor unique plant and animal communities because their waters are brackish--a mixture of fresh water draining from the land and salty seawater.Estuaries are some of the most productive ecosystems in the world. Many animal species rely on estuaries for food, places to breed, and migration stopovers. Human communities also rely on estuaries for food, recreation, jobs, and coastal protection.Of the 32 largest cities in the world, 22 are located on estuaries (e.g., New Orleans, London, etc). Not surprisingly, human activities have led to the decline in the health of estuaries, making them one of the most threatened ecosystems on the Earth. NOAA's National Estuarine Research Reserve System in partnership with coastal states monitors the health of estuaries and helps communities manage their coastal resources.

Educator, Laura K.; National Science Teachers Association (NSTA); Review, Steve W.

2005-04-01

110

Predation on Ruffe by Native Fishes of the St. Louis River Estuary, Lake Superior, 1989–1991  

Microsoft Academic Search

The ruffe Gymnocephalus cernuus, an exotic Eurasian percid, recently became es- tablished in the St. Louis River estuary. Lake Superior, after accidental introduction. Management actions (catch regulations and stockings) were enacted in 1989 to increase the density of top-level predators in the estuary, and thus to increase predation on ruffe. We conducted a field and laboratory study to determine if.

DEREK H. OGLE; JAMES H. SELGEBY; JACQUELINE E. SAVING; RAYMOND M. NEWMAN; MARY G. HENRY

1996-01-01

111

Predation on Ruffe by Native Fishes of the St. Louis River Estuary, Lake Superior, 1989–1991  

Microsoft Academic Search

The ruffe Gymnocephalus cernuus, an exotic Eurasian percid, recently became established in the St. Louis River estuary, Lake Superior, after accidental introduction. Management actions (catch regulations and stockings) were enacted in 1989 to increase the density of top-level predators in the estuary, and thus to increase predation on ruffe. We conducted a field and laboratory study to determine if, and

Derek H. Ogle; James H. Selgeby; Jacqueline E. Saving; Raymond M. Newman; Mary G. Henry

1996-01-01

112

Shark Predation on Migrating Adult American Eels (Anguilla rostrata) in the Gulf of St. Lawrence  

PubMed Central

In an attempt to document the migratory pathways and the environmental conditions encountered by American eels during their oceanic migration to the Sargasso Sea, we tagged eight silver eels with miniature satellite pop-up tags during their migration from the St. Lawrence River in Québec, Canada. Surprisingly, of the seven tags that successfully transmitted archived data, six were ingested by warm-gutted predators, as observed by a sudden increase in water temperature. Gut temperatures were in the range of 20 to 25°C—too cold for marine mammals but within the range of endothermic fish. In order to identify the eel predators, we compared their vertical migratory behavior with those of satellite-tagged porbeagle shark and bluefin tuna, the only endothermic fishes occurring non-marginally in the Gulf of St. Lawrence. We accurately distinguished between tuna and shark by using the behavioral criteria generated by comparing the diving behavior of these two species with those of our unknown predators. Depth profile characteristics of most eel predators more closely resembled those of sharks than those of tuna. During the first days following tagging, all eels remained in surface waters and did not exhibit diel vertical migrations. Three eels were eaten at this time. Two eels exhibited inverse diel vertical migrations (at surface during the day) during several days prior to predation. Four eels were eaten during daytime, whereas the two night-predation events occurred at full moon. Although tagging itself may contribute to increasing the eel's susceptibility to predation, we discuss evidence suggesting that predation of silver-stage American eels by porbeagle sharks may represent a significant source of mortality inside the Gulf of St. Lawrence and raises the possibility that eels may represent a reliable, predictable food resource for porbeagle sharks. PMID:23082131

Beguer-Pon, Melanie; Benchetrit, Jose; Castonguay, Martin; Aarestrup, Kim; Campana, Steven E.; Stokesbury, Michael J. W.; Dodson, Julian J.

2012-01-01

113

Diet and Feeding Periodicity of Ruffe in the St. Louis River Estuary, Lake Superior  

Microsoft Academic Search

Ruffe Gymnocephalus cernuus, a percid native to Europe and Asia, is established in the Lake Superior drainage and could have negative impacts on native fish through competition for forage and predation on fish eggs. We investigated the diet of ruffes in the 4,654-ha St. Louis River estuary in May–October 1989–1990 and the feeding periodicity of ruffes in two adjacent habitats

Derek H. Ogle; James H. Selgeby; Raymond M. Newman; Mary G. Henry

1995-01-01

114

Diet and Feeding Periodicity of Ruffe in the St. Louis River Estuary, Lake Superior  

Microsoft Academic Search

Ruffe Gymnocephalus cernuus, a percid native to Europe and Asia, is established in the Lake Superior drainage and could have negative impacts on native fish through competition for forage and predation on fish eggs. We investigated the diet of ruffes in the 4,654-ha St. Louis River estuary in May-October 1989-1990 and the feeding periodicity of ruffes in two adjacent habitats

DEREK H. OGLE; JAMES H. SELGEBY; RAYMOND M. NEWMAN; MARY G. HENRY

1995-01-01

115

Age and growth of lake sturgeon in the upper St. Lawrence River  

USGS Publications Warehouse

The growth of lake sturgeon (Acipenser fulvescens) over time in the upper St. Lawrence River was examined. Growth of lake sturgeon collected during 1993 and 1994 below Robert Moses Dam near Massena, New York, was compared to that reported for the same population almost 25 years earlier. The data suggest that lake sturgeon growth was similar to that reported in the previous study. However, significant differences in the elevations of regression models between males and fish of unknown sex in both data sets suggest possible sexual dimorphism in growth at younger ages.

Johnson, J.H.; Dropkin, D.S.; LaPan, S.R.; McKenna, J.E., Jr.; Klindt, R.M.

1998-01-01

116

Mapping ecosystem services in the St. Louis River Estuary  

EPA Science Inventory

Sustainable management of ecosystems for the perpetual flow of services beneficial to human communities requires reliable data about from where in the ecosystem services flow. Our objective is to map ecosystem services in the St. Louis River with the overarching U.S. EPA goal of ...

117

Great Lakes-St. Lawrence Maritime Initiative Consultant Request for Proposal  

E-print Network

The Council of Great Lakes Governors (CGLG) seeks to hire a consultant or consulting firm (consultant), part-time. The primary role of the consultant will be to analyze the Great Lakes-St. Lawrence River maritime transportation system and develop recommendations that will ultimately be shared with the Great Lakes Governors and Premiers for their consideration in the development of policies to be adopted and programs that may be implemented. This position requires experience on port, transportation and maritime issues. The consultant will work closely with the CGLG staff and will report to the Executive Director. The consultant will also work closely with the Great Lakes-St. Lawrence River Maritime Task Force (Task Force) as well as other staff designated by the Great Lakes States, Ontario and Québec. The CGLG will enter into a fixed fee contract for consulting services at a non-negotiable amount of $50,000. All costs including staff salaries, office space/rent, office equipment, office supplies, postage, printing, telephones, local transportation and all other costs unless otherwise noted will be the sole responsibility of the consultant and derived from the contract fee. The CGLG will pay for pre-authorized travel expenses related to Task Force meetings, or for additional preauthorized expenses incurred for activities outside of the scope of the consultant’s contract with the CGLG.

unknown authors

2013-01-01

118

Genotoxic substances in the St. Lawrence system II: Extracts of fish and macroinvertebrates from the St. Lawrence and Saguenay Rivers, Canada  

SciTech Connect

Aquatic biota frequently accumulate organic contaminants and maintain steady state tissue concentrations that are as much as 10{sup 5} times higher than those in the surrounding water. Although many researchers have studied the accumulation of genotoxic polycyclic aromatic hydrocarbons (PAHs) by aquatic biota, few researchers have used bioassays to investigate the accumulation of genotoxins. In several previous studies the authors used the SOS Chromotest to investigate the genotoxicity of industrial effluent extracts, sediment extracts, and bivalve tissue extracts. In this study they use the SOS Chromotest to investigate the accumulation of organic genotoxins by macroinvertebrates and fish in the St. Lawrence and Saguenay rivers (Quebec, Canada). Tissue concentrations of genotoxins reveal bioconcentration factors in the 10{sup 2} to 10{sup 3} range. Concentrations are partially determined by lipid content (r{sup 2} = 0.22). Lipid-normalized values indicate that genotoxin concentrations in invertebrate tissues are significantly higher than those in fish. Fish values indicate that tissue concentrations are biodiminished, with fish at higher trophic levels having lower tissue burdens of genotoxins. The biodiminution pattern observed corresponds exceptionally well with trophic position assignments made by other authors. More contaminated sites yielded less contaminated specimens. This may be due to the induction of phase 1 and phase 2 detoxification enzymes that is likely to occur at high levels of exposure. Although the results do not support PAHs as the putative genotoxins, the results do indicate that the accumulated genotoxins have similar properties. Tissue to sediment ratios of genotoxins are similar to those observed for genotoxic PAHs, and far lower than those of more persistent organochlorines. Although the authors did not investigate genotoxic effects, they might expect the most dramatic effects in fish that consume contaminated macroinvertebrates.

White, P.A.; Rasmussen, J.B. [McGill Univ., Montreal, Quebec (Canada). Dept. of Biology; Blaise, C. [Environment Canada, Montreal, Quebec (Canada). St. Lawrence Center

1998-02-01

119

Population Characteristics and Contaminant Burdens of the White Sucker ( Catostomus commersoni) from the St. Lawrence River near Cornwall, Ontario and Massena, New York  

Microsoft Academic Search

The objective of this study was to compare ecological and chemical characteristics of two populations of white sucker (Catostomus commersoni) (n = 762) upstream and downstream of the Moses-Saunders power dam in the St. Lawrence River. The downstream section of the St. Lawrence River near Cornwall, Ontario and Massena, New York is an International Joint Commission Area of Concern (AOC).

Lara L. Ridgway; François Chapleau; Michael E. Comba; Sean M. Backus

1999-01-01

120

January snow accumulation in the St. Lawrence Valley (1961-1990)  

NASA Astrophysics Data System (ADS)

Located in Eastern Canada, the St. Lawrence Valley (between Montreal and Quebec City; ±350 km) is known as one of the snowiest populated valleys in the world. Usually more than 250 cm of snow falls every winter. Snowstorms are frequent, as more than 10 major snowstorms are registered every year [1] interfering greatly with human activities. Numerical analyses (univariate analysis, discriminant analysis and stepwise multiple regression) for the 1961-1990 period on total snow depth for the month of January reveals three winter-regional climates along this valley: A-) the southern part of Montreal; slightly warmer with less snow and less rainfall, B-) the area around Quebec City; colder with more snow and C-) an intermediate corridor in-between those two cities. Two major variables were identified as responsible for explaining these three winter regional climates: maximum temperature and rainfall.

Toupin, Jerry

2009-09-01

121

Isotopic monitoring (2H, 18O) of the St. Lawrence and Ottawa rivers between 1997 and 2003- Links with interannual climatic variability and hydrological processes in their catchment basins  

NASA Astrophysics Data System (ADS)

This study based on a water isotope (18O and 2H) monitoring of the St. Lawrence and Ottawa rivers (Canada) is a contribution to the international IAEA project: Isotopes tracing of hydrologic processes in large river basins [Gibson et al., 2002. EOS 83: 613 et p.]. Sampling of the St. Lawrence and Ottawa river waters started in 1997, on a biweekly to weekly basis. Monitoring stations are located at Montreal (i.e., at the outlet of the Great Lakes), Quebec City (the estuary of the St. Lawrence) and at the Carillon hydroelectric dam, near the outlet of a major tributary, the Ottawa River into the St. Lawrence itself. The goal of the study was to examine the seasonal and interannual variability of isotopic signatures of the St. Lawrence and Ottawa rivers, in relation notably with interannual climatic variations, and seasonal hydrologic processes in the watershed (summer evaporation, snowmelt, transit time of precipitation signals into runoff). Waters sampled at the three stations depict distinct isotopic compositions. At Montreal, relatively stable isotopic composition are observed with a mean weighted annual value of -54 % for 2H and -7.1 % for 18O. The Ottawa River water at Carillon also displays stable isotopic compositions but much lighter values (weighted mean annual values: -80 % for 2H and -10.8 % for 18O). Finally, isotopic compositions at Quebec City are intermediate between those of Montreal and Carillon, but show a much larger variability. They reflect mixing between the heavy isotope enriched Great Lakes water, the lighter water from the Ottawa River, and highly variable inputs from smaller tributaries (from the Laurentides and Appalachian mountains). The mean weighted isotopic compositions at Quebec City are -65 % and -8.6 %, respectively for 2H and 18O). Evaporative enrichment, in particular during low water level episodes, seem to be more important in the Ottawa River catchment than in the Great Lakes basin, based on a comparison of isotopic clusters at Montreal and Carillon (figure 1). Relatively strongly correlated relationships are observed between isotopic compositions at the estuary of the St. Lawrence River (Quebec) and hydrologic variables such as water discharge. The best fit follows the equation : 2HQUEBEC = -1.9E-03 * QQUEBEC - 41.9, R2= 0.59. Such a relationship leads us to conclude that some properties of the regional hydrology can be relatively well described by stable isotope systematics. In contradiction, air temperatures are not well correlated with isotopic signatures partly because of lag times between them in relation to transit time of precipitation signal into runoff. A comparison of isotopic values in precipitation to those of runoff gives an estimate of the mean transfer time of water from the catchment to the river estuary. For summer heavy isotope enriched, but scarcer precipitation, a transit time of approximately 3 months is observed, whereas in winter, it can be as long as 4 to 5 months due to the residence time of winter precipitation in the snowcover. The assessment of the interannual variability of the St. Lawrence River isotopic system will require a better estimate of the isotopic inprint from small tributaries (that drain isotopically buffered ground waters, particularly in winter). Data are presently at processing stage.

Myre, A.; Hillaire-Marcel, C.

2004-05-01

122

Trophic structure and mercury distribution in a Gulf of St. Lawrence (Canada) food web using stable isotope analysis  

Microsoft Academic Search

Even at low concentrations in the environment, mercury has the potential to biomagnify in food chains and reaches levels of concern in apex predators. The aim of this study was to relate the transfer of total mercury (THg) and methylmercury (MeHg) in a Gulf of St. Lawrence food web to the trophic structure, from primary consumers to seabirds, using stable

Raphael A. Lavoie; Craig E. Hebert; Jean-François Rail; Birgit M. Braune; Emmanuel Yumvihoze; Laura G. Hill; David R. S. Lean

2010-01-01

123

Distribution and fluxes of metals in the St. Lawrence River from the outflow of Lake Ontario to Québec City  

Microsoft Academic Search

Six anchor stations in the St. Lawrence River from the outflow of Lake Ontario to Quebec City, were occupied for ca. 24 hours in June 1987 during low flow conditions. Samples of water and suspended particulate matter were separated by continuous-flow centrifugation, and were collected every two hours.

Ken R. Lum; K. L. E. Kaiser; C. Jaskot

1991-01-01

124

?-carotene and retinoids in eggs of Great Blue Herons (Ardea herodias) in relation to St Lawrence River contamination  

Microsoft Academic Search

The potential use of retinoids and ß-carotene as biomarkers in the eggs of the Great Blue Heron was investigated. In the spring of 1991, 65 eggs were collected from nine heronries (seven along the St Lawrence River and two reference sites). A method was specifically developed for the extraction and analysis of ß-carotene and the retinoids in heron egg yolks

M. H. Boily; L. Champoux; D. H. Bourbonnais; J. L. Granges; J. Rodrigue; P. A. Spear

1994-01-01

125

Made in Japan: The Japanese market and herring roe production and management in Canada's southern Gulf of St. Lawrence  

Microsoft Academic Search

The herring roe fishery in Canada's southern Gulf of St. Lawrence is a productive fishery that lies outside the confines of privatized arrangements. Yet, this fishery is compromised by its dependence on the Japanese seafood market. Consideration of the efficiency of this fishery needs to account for the role assumed by this market in setting fishing practices. A more ecologically

Lenore Burke; John Phyne

2008-01-01

126

Quagga mussels ( Dreissena bugensis) as biomonitors of metal contamination: A case study in the upper St. Lawrence River  

Microsoft Academic Search

In this study, the utility of quagga mussels (Dreissena bugensis) as biomonitors was investigated by measuring total concentrations of three trace metals, cadmium, copper, and zinc, in soft tissues. Quagga mussels were sampled from five sites along the upper St. Lawrence River, including one industrially influenced site, from 1999 through 2007. Mussels were collected from near-shore areas, divided into 5

Carolyn Johns

2011-01-01

127

Spatial Distribution of Total Cadmium, Copper, and Zinc in the Zebra Mussel ( Dreissena polymorpha) Along the Upper St. Lawrence River  

Microsoft Academic Search

The zebra mussel (Dreissena polymorpha) was utilized to assess the spatial distribution of three trace metals, cadmium, copper, and zinc, in the upper St. Lawrence River and to test the hypothesis that outflow from Lake Ontario influenced levels of these metals in near-shore biota. Zebra mussels, collected from twelve sites along the southern shore, were analyzed for total cadmium, copper,

Carolyn Johns

2001-01-01

128

Ground-water quality and data on wells and springs in Pennsylvania; Volume I, Ohio and St. Lawrence River basins  

USGS Publications Warehouse

Volume I of the Groundwater Quality and Data on Wells and Springs in Pennsylvania presents groundwater quality and physical data on about 1,200 well and spring sites in the Ohio and St. Lawrence River basins. Locations are shown on site-location maps derived from the hydrologic unit map. Codes showing the geologic age and aquifer are provided. (USGS)

Koester, Harry E.; Miller, Denise R.

1980-01-01

129

Development of a 3-D geological model towards natural hazards mitigation, St. Lawrence River Valley, Eastern Canada  

Microsoft Academic Search

As part of the Canadian Government's main goals to ensure safe and strong communities for its citizens, the Geological Survey of Canada has recently undertaken the development of a 3-D geological model and a seamless surficial geology map of the St. Lawrence River valley in Eastern Canada. This paper summarizes the initial phase of this project, which consists of gathering,

RÉJEAN COUTURE; DOMINIQUE GAUVREAU; J. ROBERT BÉLANGER

130

Marine boating habits and the potential for spread of invasive species in the Gulf of St. Lawrence  

Microsoft Academic Search

The potential for boating to disperse the clubbed tunicate Styela clava Herdman, 1881 and green crab Carcinus maenas (Linnaeus, 1758) in the southern Gulf of St. Lawrence was investigated using interviews with recreational and commercial boaters in eastern Prince Edward Island (PEI). Boaters were asked how long their boat had been at the present location; the primary use of the

Emily Darbyson; Andrea Locke; John Mark Hanson; J. H. Martin Willison

2009-01-01

131

Estuaries  

NSDL National Science Digital Library

An estuary is a body of water that is created when freshwater from rivers and streams flows into the saltwater of an ocean. To understand this mixing of fresh and salt water, learners go through several activities: 1) in Salt and Water, learners dissolve salt crystals in water to observe their effects on water; 2) in Making a Salt Wedge, learners make a model of a salt wedge estuary, which occurs in nature when the mouth of a river flows directly into seawater; 3) in Plant Dehydration learners observe the effects of salinity (salt content in the water) on live plants. Includes a wrap-up guide for group discussions.

Jersey, New; Center, Liberty S.; Coalition, New J.

2006-01-01

132

Fish Community Changes in the St. Louis River Estuary, Lake Superior, 1989–1996: Is It Ruffe or Population Dynamics?  

Microsoft Academic Search

Ruffe (Gymnocephalus cernuus) have been implicated in density declines of native species through egg predation and competition for food in some European waters where they were introduced. Density estimates for ruffe and principal native fishes in the St. Louis River estuary (western Lake Superior) were developed for 1989 to 1996 to measure changes in the fish community in response to

Charles R. Bronte; Lori M. Evrard; William P. Brown; Kathleen R. Mayo; Andrew J. Edwards

1998-01-01

133

A survey of the St. Louis River estuary with emphasis on non-indigenous species and habitat structure  

EPA Science Inventory

As part of a larger study to develop a monitoring network for aquatic non-indigenous species (NIS), a comprehensive multi-gear survey of larval fish and macroinvertebrates in the St. Louis River estuary was conducted during summer 2012. A total of 139 larval fish samples and 118...

134

Shoreline Classification of the St. Louis River Estuary using Geographic Information Systems and Standard Landuse/Landcover Data Sets  

EPA Science Inventory

The St. Louis River Estuary (SLRE) shoreline is ~300 km in length and borders MN and WI from the MN highway 23 downstream to Lake Superior. The shoreline is a complex and diverse mixture of many features from industrial docks and slips in the lower SLRE to complex wetlands and na...

135

Spatial and temporal variation in abundance of Diplostomum spp. in walleye ( Stizostedion vitreum ) and white suckers ( Catostomus commersoni ) from the St. Lawrence River  

Microsoft Academic Search

Abundances of eye flukes (Diplostomum spp.) were compared between walleye (Stizostedion vitreum) and white suckers (Catostomus commersoni ) collected in late summer 1997 from Lake St. Louis and Lake St. Pierre, two expansions of the St. Lawrence River in Quebec, Canada. The white sucker, a benthic consumer, was more heavily in- fected than the walleye, a pelagic piscivore, in both

David J. Marcogliese; Pierre Dumont; Andrée D. Gendron; Yves Mailhot; Emmanuelle Bergeron; J. Daniel McLaughlin

2001-01-01

136

Toxicity of sediments near an aluminum smelter on the St. Lawrence river to aquatic organisms  

SciTech Connect

Under a US EPA Superfund Administrative Order, over 50,000 cu yds of bottom sediments contaminated with fluoride, cyanide, PCBs, PAHs and Al will be dredged from the St. Lawrence River near the Reynolds Metals plant at Massena, NY in 1994. The purpose of this study was to determine the toxicity of these sediments to aquatic organisms and the potential for remobilizing sediment-bound contaminants into the water column during dredging. Sediment was collected from 7 sites along a gradient from the outfall in October 1993. Sediment from the most contaminated site ``B2`` (1,500 {mu}g/g fluoride, 30 {mu}g/g cyanide, 450 {mu}g/g PCBs, 3,500 {mu}g/g PAHs, 90,000 {mu}g/g Al), caused complete mortality of mayflies, Hexagenia limbata, and avoidance, considerable weight loss and some mortality in fathead minnows, Pimephales promelas, after 21 d exposure. Mortality was not observed at other sites, but growth of both organisms decreased with increasing contamination. LOECs of B2 elutriate were 13% for survival and reproduction of Ceriodaphnia dubia, and 6% for survival and 1.5% for growth of larval fatheads. Elutriates of other sediments were nontoxic. TIE testing suggested organic contaminants as the primary toxicants. Over 2,000 cu yds of sediment are highly toxic and 18,000 cu yds somewhat toxic. Toxicity of B2 elutriate shows that contaminants enter the water column when sediments are disturbed and may harm indigenous biota.

Metcalfe-Smith, J.L. [National Water Research Inst., Burlington, Ontario (Canada); Sirota, G.R.; Holtze, K.E.; Reid, J.J. [B.A.R. Environmental Inc., Guelph, Ontario (Canada)

1994-12-31

137

Late Quaternary history of the southwestern St. Lawrence Lowlands and adjacent Adirondack Highlands  

SciTech Connect

The reconstruction of Late Wisconsinan ice retreat, proglacial lakes, and Champlain Sea history from the northwest Adirondack slope and adjacent St. Lawrence Lowlands is critical to the synthesis of a regional picture of deglacial events in the eastern Great Lakes region. Unfortunately, these same areas are well known for their limited exposures, landforms covered by thick forest, large tracts of land inaccessible to detailed field mapping, and the overall paucity of glacial materials preserved on upland surfaces. Despite these limitations, a model which utilizes multiple and field-truthed evidence has been used to designate areas where ice border deposits indicate a substantial recessional position. It employs the following criteria in this analysis: sedimentology and morphostratigraphy of morainal landform segments and related sediments; orientation and continuity of ice border drainage channels; and the relationship of ice borders and drainage systems to well documented local and regional water bodies which accompanied ice retreat. The results of this approach have provided a unique regional picture of deglaciation. Despite the inherent limitations of working in upland areas to reconstruct glacial events, detailed morphostratigraphic correlations based on multiple lines of evidence can yield important information. The positions of five former ice borders have been reconstructed from the available data. These ice margins correspond closely with those documented previously by others adjoining areas. This type of study, utilizing multiple and field-truthed lines of evidence, constitutes a tangible step towards understanding the nature and history of ice retreat along this portion of the Laurentide Ice Sheet.

Pair, D.L. (Univ. of Dayton, OH (United States). Dept. of Geology)

1993-03-01

138

Lake sturgeon spawning on artificial habitat in the St Lawrence River  

USGS Publications Warehouse

In 1996, lake sturgeon (Acipenser fulvescens) spawning was documented for the third consecutive year on an artificially placed gravel bed in the St Lawrence River. Two distinct spawning periods were observed in 1996. Spawning initially commenced on 17 June, when water temperature reached 15??C. A second spawning event was documented from 28 June to 1 July (16??C). Sturgeon egg densities were monitored in three transects on egg trays, on the gravel surface, and within interstitial spaces in the gravel. Counts of developing eggs in the gravel bed during both spawning periods were used to estimate a total of 275000 eggs on the study area (0.075 ha). Average egg density was highest in the transect with the highest water velocities. Lake sturgeon fry were first observed in the gravel on 24 June (15.5??C), and first emergence from the gravel was documented on 28 June. Hatching following the second spawning event commenced on 3 July. Based on assessment of average embryo viability (61.6%) and egg-to-emergent fry survival (17.6%) an estimate of about 171000 sturgeon eggs hatched, producing over 49000 emergent fry. Current velocity, substrate particle size, depth of substrate, and maintenance of sediment-free interstitial spaces are important considerations in planning future spawning habitat enhancement projects. ?? Journal compilation 2006 Blackwell Verlag, Berlin.

Johnson, J.H.; LaPan, S.R.; Klindt, R.M.; Schiavone, A.

2006-01-01

139

Novel brominated flame retardants and dechloranes in three fish species from the St. Lawrence River, Canada.  

PubMed

Restrictions in the utilization of polybrominated diphenyl ether (PBDE) mixtures have led to the increased usage of alternative flame retardant additives in a wide range of commercial applications. The present study examined the occurrence of established and emerging flame retardants (FRs) in fish from a densely-populated urbanized sector of the St. Lawrence River (Montreal, Quebec, Canada). Thirty-eight PBDE congeners and sixteen emerging FRs were determined in fish belonging to three predatory species (yellow perch, northern pike, and muskellunge). The ?PBDE in fish were up to 24,115 ng/g lipid weight (l.w.) in the apex predator muskellunge. Twelve emerging FRs including bis(2-ethylhexyl)-tetrabromophthalate (BEHTBP), pentabromoethylbenzene (PBEB), Dechlorane Plus (anti and syn), dechloranes (Dec) 602, Dec 604, Dec 604 Compound B (Dec 604 CB), and Chlordene Plus (CP) were detected (>0.01 ng/gl.w.) in the liver of muskellunge and northern pike but not in yellow perch homogenates. This is the first report of Dec 604 CB in any fish species. The bioavailability of these FRs in human-impacted aquatic ecosystems warrants further environmental assessment and toxicity testing. PMID:24534698

Houde, Magali; Berryman, David; de Lafontaine, Yves; Verreault, Jonathan

2014-05-01

140

Parasite fauna of Etheostoma nigrum (Percidae: Etheostomatinae) in localities of varying pollution stress in the St. Lawrence River, Quebec, Canada  

Microsoft Academic Search

Parasite communities were examined in johnny darters (Etheostoma nigrum) collected from five localities in the St. Lawrence River in southwestern Quebec: two reference localities, one polluted\\u000a locality upstream of the Island of Montreal and downstream of industrial and agricultural activity, and two polluted localities\\u000a downstream of the Island of Montreal in the plume from the wastewater treatment facility. Twenty-four helminth

Rachel J. Krause; J. Daniel McLaughlin; David J. Marcogliese

2010-01-01

141

Historical changes in herbaceous wetland distribution induced by hydrological conditions in Lake Saint-Pierre (St. Lawrence River, Quebec, Canada)  

Microsoft Academic Search

Historical changes (1961–2002) in the distribution of herbaceous wetland plant associations were inferred from the hydrological regime of Lake Saint-Pierre, a 312 km2 broadening of the St. Lawrence River (Quebec, Canada), to assess the cumulative effects of human interventions and climatic variability. Relative abundance index (height × percent cover) of wetland plants in 630 field quadrats sampled at 13 sites (1999–2002)

Christiane Hudon; Pierre Gagnon; Jean-Pierre Amyot; Guy Létourneau; Martin Jean; Céline Plante; Daniel Rioux; Martin Deschênes

2005-01-01

142

Seasonal variability of denitrification efficiency in northern salt marshes: An example from the St. Lawrence Estuary  

Microsoft Academic Search

In coastal ecosystems, denitrification is a key process in removing excess dissolved nitrogen oxides and participating in the control of eutrophication process. Little is known about the role of salt marshes on nitrogen budgets in cold weather coastal areas. Although coastal salt marshes are important sites for organic matter degradation and nutrient regeneration, bacterial-mediated nitrogen cycling processes, such as denitrification,

Patrick Poulin; Emilien Pelletier; Richard Saint-Louis

2007-01-01

143

Trace metals in the Columbia River Estuary following the 18 May 1980 eruption of Mount St. Helens  

SciTech Connect

Dissolved and suspended concentrations of cadmium, copper, iron, manganese, nickel, lead, and zinc were measured in the Columbia River Estuary following the 18 May 1980 eruption of Mount St. Helens. Soluble concentrations of these trace elements were not substantially elevated by the influx of volcanic ash and mud into the estuary during this period, except for somewhat higher than usual concentrations of manganese and copper. A laboratory experiment indicates that manganese leached from volcanic debris in fresh water and in the transition from fresh to slightly saline water probably caused the elevated Mn leaching from the material into fresh water.

Riedel, G.F.; Wilson, S.L.; Holton, R.L.

1984-10-01

144

Ground-Water Quality in the St. Lawrence River Basin, New York, 2005-06  

USGS Publications Warehouse

The Federal Clean Water Act requires that States monitor and report on the quality of ground water and surface water. To satisfy part of these requirements, the U.S. Geological Survey and New York State Department of Environmental Conservation have developed a program in which ground-water quality is assessed in 2 to 3 of New York State's 14 major river basins each year. To characterize the quality of ground water in the St. Lawrence River Basin in northern New York, water samples were collected from 14 domestic and 11 production wells between August 2005 and January 2006. Eight of the wells were finished in sand and gravel and 17 wells were finished in bedrock. Ground-water samples were collected and processed using standard U.S. Geological Survey procedures and were analyzed for 229 constituents and physical properties, including inorganic constituents, nutrients, trace elements, radon-222, pesticides and pesticide degradates, volatile organic compounds, and bacteria. Sixty-six constituents were detected above laboratory reporting levels. Concentrations of most compounds at most sites were within drinking water standards established by the U.S. Environmental Protection Agency and New York State Department of Health, but a few compounds exceeded drinking water standards at some sites. Water in the basin is generally hard to very hard (hardness equal to 121 mg/L as CaCO3 or greater); hardness and alkalinity were generally higher in the St. Lawrence Valley than in the Adirondack Mountains. The cation with the highest median concentration was calcium; the anion with the highest median concentration was bicarbonate. The concentration of chloride in one sample exceeded the 250 milligrams per liter U.S. Environmental Protection Agency Secondary Drinking Water Standard; the concentration of sulfate in one sample also exceeded the 250 milligrams per liter U.S. Environmental Protection Agency Secondary Drinking Water Standard. Nitrate was the predominant nutrient detected but no sample exceeded the 10 mg/L U.S. Environmental Protection Agency Maximum Contaminant Level. The trace elements detected with the highest median concentrations were strontium, barium, and iron. Concentration of trace elements in several samples exceeded U.S. Environmental Protection Agency Secondary Drinking Water Standards, including aluminum (50 micrograms per liter, 4 samples), iron (300 micrograms per liter, 5 samples), and manganese (50 micrograms per liter, 4 samples). The concentration of uranium in one sample from a domestic well finished in crystalline bedrock was three times the U.S. Environmental Protection Agency Maximum Contaminant Level of 30 micrograms per liter. The median concentration of radon-222 was 600 picoCuries per liter, but concentrations as high as 18,800 picoCuries per liter were detected; two wells with high radon concentrations also had high uranium concentrations. Radon-222 is not currently regulated, but the U.S. Environmental Protection Agency has proposed a Maximum Contaminant Level of 300 picoCuries per liter along with an Alternative Maximum Contaminant Level of 4,000 picoCuries per liter, to be in effect in states that have programs to address radon in indoor air. Concentrations of radon-222 exceeded the proposed Maximum Contaminant Level in 60 percent of samples and exceeded the proposed Alternative Maximum Contaminant Level in 8 percent of samples. Six pesticides and pesticide degradates were detected; all were amide or triazine herbicides or degradates. Five volatile organic compounds were detected, including disinfection byproducts such as trichloromethane and gasoline components or additives such as methyl tert-butyl ether. No pesticides, pesticide degradates, or volatile organic compounds were detected above established limits. Coliform bacteria, including Escherichia coli, were detected in three wells finished in carbonate bedrock.

Nystrom, Elizabeth A.

2007-01-01

145

Alternative nursery habitat for estuarine associated marine fish during prolonged closure of the St Lucia estuary, South Africa  

NASA Astrophysics Data System (ADS)

The Mfolozi estuary, located on the east coast of South Africa, was historically directly linked to the adjacent St Lucia estuarine system, the largest estuarine system in Africa and a World Heritage Site. The Mfolozi used to be the main feeder system to maintain lake levels in St Lucia, but increased siltation from sugar cane farming in the Mfolozi floodplain led to artificial separation of the two systems in 1950. Reduced freshwater inflow due to drought conditions caused the St Lucia mouth to remain closed from June 2002 to present, coinciding with low lake levels and hypersaline conditions, except for a brief period during 2007 after the St Lucia mouth breached. These conditions led to disruption of larval recruitment into the system and major changes in biotic communities. Due to the importance of the St Lucia - Mfolozi System link, a study was initiated in 2007 on the fish community of the Mfolozi system, which was sampled using seine and gill nets. The 48 species recorded were dominated by juveniles of marine spawners, particularly Leiognathus equula and Valamugil cunnesius and the estuarine spawners Ambassis dussumieri and Ambassis natalensis. Estuarine dependent marine spawning species formed 68% of both the species numbers and CPUE, an indication of the regional importance of the Mfolozi estuary as an alternate refuge for juvenile marine fish during periods when the St Lucia system remained closed. Post-larval recruits of marine spawning species were particularly abundant, but low zoobenthic densities caused a rapid decline in numbers of benthic feeders shortly after their recruitment into the system. The importance of the Mfolozi estuary in maintaining marine brood stocks of estuarine dependent marine fish is discussed with particular reference to estuarine degradation and the ecological integrity of the St Lucia system.

Vivier, Leon; Cyrus, Digby P.

2009-10-01

146

Study on subtidal circulation and variability in the Gulf of St. Lawrence, Scotian Shelf, and Gulf of Maine using a nested-grid shelf circulation model  

NASA Astrophysics Data System (ADS)

This paper examines the subtidal circulation and associated variability in the Gulf of St. Lawrence, the Scotian Shelf, and the Gulf of Maine (GSL-SS-GOM) in 1988-2004 based on results produced by a nested-grid shelf circulation model. The model has a fine-resolution child model (˜ (1/12)°) embedded inside a coarse-resolution parent model (˜ (1/4)°) of the northwest Atlantic. The combination of the semi-prognostic method and the spectral nudging method is used to reduce the model seasonal bias and drift. The child model reproduces the general features of the observed circulation and hydrography over the study region during the study period. The child model results demonstrate that the time-mean circulation in the GSL is affected by the time-mean atmospheric forcing and inflow through the Strait of Belle Isle. The temporal variability in atmospheric forcing affects the outflow through western Cabot Strait, which in turn affects the transport of the Nova Scotian Current and the gulf-wide cyclonic circulation in the GOM. The simulated seasonal variability of salinity in the top 30 m of the GSL-SS-GOM is mainly affected by the equatorward advection of low-salinity waters from the lower St. Lawrence Estuary to the GOM through the Scotian Shelf. The simulated intraseasonal variability of circulation in the GSL is affected by the variability in the estuarine circulation in response to the temporal variability in atmospheric forcing. On the Scotian Shelf, the intraseasonal variability is mainly driven by the variability of wind forcing and mesoscale and nonlinear dynamics over the shelf break and slope region. The interannual variability in the simulated temperature and salinity are spatially coherent in the intermediate waters in the GSL, which is caused partially by the local response to atmospheric variability and partially by variabilities over the southern Newfoundland Shelf that enter the GSL through the eastern Cabot Strait. By comparison, on the Scotian Shelf, the interannual variability of simulated circulation is affected by anomalies produced by the nonlinear dynamics which are advected equatorwards by the shelf break jet.

Urrego-Blanco, Jorge; Sheng, Jinyu

2014-03-01

147

Index of surface-water records, part 4, St. Lawrence River Basin, to September 30, 1950  

USGS Publications Warehouse

The index lists the stream-flow and reservoir stations in the St. Lawrence River Basin for which records have been or are to be published for periods prior to September 30, 1950. The stations are listed in downstream order. Tributary streams are indicated by indention. Station names are given in their most recently published forms. Parentheses around part of a station name indicate that the inclosed word or words were used in an earlier published name or the station or in a name under which records were published by same agency other than the Geological Survey. The drainage areas, in square miles, are the latest figures published or otherwise available at this time. Drainage areas that were obviously inconsistent with other drainage areas on the same stream have been omitted. Some drainage areas not published by the Geological Survey are listed with an appropriate footnote stating the published source or the figure or drainage area. Under "period of record" breaks of less than a 12-month period are not shown. A dash not followed immediately by a closing date shows that the station was in operation on September 30, 1950. The years given are calendar years. Periods of records published by agencies other than the Geological Survey are listed in parentheses only when they contain more detailed information or are for periods not reported in publications to the Geological Survey. Records both of gage height and of discharge are listed for stream-flow stations, and records of gage height and of contents (or of change in contents) are listed for stations on reservoirs. Records of gage heights only and records consisting only of monthly figures either of stream flow or reservoir contents are designated by symbols and footnotes. For early years when daily discharges were not generally published by the Geological Survey, published daily gage heights and a published rating table are considered to be equivalent to daily discharges. An alphabetical index of streams. canals. and reservoirs is given on pages 12 to 14.

1951-01-01

148

Crustal Structure Beneath the Gulf of ST. Lawrence, Atlantic Canada, from Ambient Seismic Noise Tomography  

NASA Astrophysics Data System (ADS)

The Gulf of St. Lawrence (GSL), located north of the southwest-northeast trending Appalachian mountain in eastern Canada, is a major sedimentary basin with huge potentials for hydrocarbon accumulation. Important questions about the geometry and evolution of the crustal and basin structure beneath the gulf are yet to be answered. To address these issues, the Geological Survey of Canada (GSC) with support from the Portable Observatories for Lithospheric Analysis and Research Investigating Seismicity (POLARIS) deployed a temporary array of broadband seismic stations in the GSL region between October 2005 and October 2008. Combined with the permanent stations of the Canadian National Seismograph Network (CNSN) in the region, the station density is sufficient for detailed seismic tomography inversion. In this study, we investigate the upper crustal structure beneath the gulf using 3 years of continuous ambient noise waveforms recorded at 25 (POLARIS and CNSN) stations around the GSL. Cross-correlation functions of the vertical component of the ambient noise wavefield for simultaneously recording station pairs (corresponding to inter-station Green's functions) are computed and analyzed using the frequency-time analysis method. Dispersion curves are measured and Rayleigh wave group velocities are subsequently extracted for periods between 2 and 20s, which are periods sensitive to the upper crustal structures. Preliminary results from the dispersion measurements indicate that mean group velocities in the region range from 2.8 to 3.2 km/s across the range of period specified. 2-D group velocity distribution for each period is determined by linearized inversion of the dispersion data. Our tomography results show prominent lateral velocity variation. Low velocity anomalies are observed at shorter periods (up to ~10 s) which correspond to the sedimentary structures at shallow depths (between 5-10 km), whereas the characteristics of upper crustal structures are shown by velocity anomalies at longer periods. Our results show striking similarities with the tomographic images obtained in the previous Canada-wide ambient noise analysis for areas where both studies overlap and are also consistent with results from receiver function and active seismic profiling studies previously done in the region. A detailed inversion of the 3-D shear velocity structure will be conducted to appropriately delineate the thickness and seismic velocity of the composite geologic units.

Kuponiyi, A.; Kao, H.; Cassidy, J. F.; Spence, G.

2013-12-01

149

Exploratory assessment of fish consumption among Asian-origin sportfishers on the St. Lawrence River in the Montreal region  

SciTech Connect

An exploratory survey was undertaken in the fall 1995 open-water fishing seasons with nine Bangladeshi and nine Vietnamese-origin sportfishers. A 70-item instrument assessing sportfishing practices and fish consumption habits was administered by dietitians in participants` homes. Two 24-h diet recalls and a fish consumption calendar permitted the assessment of fish intake in the overall dietary context. Annually, Bangladeshi fishers consumed 46.8 {+-} 25.6 sportfish meals, and Vietnamese fishers ate 40.7 {+-} 35.1 meals. Consumption of sportfish taken from the St. Lawrence River has the potential both for dietary benefit and for hazardous chemical exposure.

Shatenstein, B. [Sante au Travail et Environnementale, Montreal, Quebec (Canada). Regie Regionale de la Sante et des Services Sociaux de Montreal-Centre] [Sante au Travail et Environnementale, Montreal, Quebec (Canada). Regie Regionale de la Sante et des Services Sociaux de Montreal-Centre; [Univ. de Montreal, Quebec (Canada). Dept. de Nutrition; Kosatsky, T.; Tapia, M.; Nadon, S.; Leclerc, B.S. [Sante au Travail et Environnementale, Montreal, Quebec (Canada). Regie Regionale de la Sante et des Services Sociaux de Montreal-Centre] [Sante au Travail et Environnementale, Montreal, Quebec (Canada). Regie Regionale de la Sante et des Services Sociaux de Montreal-Centre

1999-02-01

150

Diet and feeding periodicity of ruffe in the St. Louis River estuary, Lake Superior  

USGS Publications Warehouse

Ruffe Gymnocephalus cernuus, a percid native to Europe and Asia, is established in the Lake Superior drainage and could have negative impacts on native fish through competition for forage and predation on fish eggs. We investigated the diet of ruffes in the the 4,654-ha St. Louis River estuary in May-October 1989-1990 and the feeding periodicity of ruffes in two adjacent habitats during 5 24-h periods in summers 1990-1991. Ruffes were primarily benthophagous. Age-0 ruffes fed mostly on cladocerans and copepods in early summer and midge larvae (Chironomidae) in late summer and fall. Adult ruffes less than 12 cm fed mostly on midges and other macrobenthos but also consumed large numbers of microcrustaceans. Adult ruffes 12 cm and larger fed mostly on midges, burrowing mayflies Hexagenia spp., and caddisflies (Trichoptera). Ruffes consumed few fish eggs. Adult ruffes in deeper waters and all age-0 ruffes fed throughout the day as indicated by weight patterns of stomach contents. However, adult ruffes generally moved to shallower waters at night to feed most heavily. Results of this study indicate that ruffes will probably compete with other benthic-feeding fishes such as yellow perch Perca flavescens and trout-perch Percopsis omiscomaycus.

Ogle, Derek H.; Selgeby, James H.; Newman, Raymond M.; Henry, Mary G.

1995-01-01

151

Induction of gene responses in St. Lawrence River northern pike (Esox lucius) environmentally exposed to perfluorinated compounds.  

PubMed

Municipal waste water effluents (MWWEs) are important sources of chemical contamination for aquatic environments. This study investigated the presence and effects of perfluorinated compounds (PFCs) in environmentally exposed northern pike (Esox lucius) collected upstream and downstream a major municipal waste water treatment plant (WWTP) in the St. Lawrence River, Canada. Twelve PFCs, including the newly detected perfluoroethylcyclohexane sulfonate (PFECHS), were quantified in fish muscle, liver, and plasma. Additionally, the expression of eight genes and the activity of three biomarkers were analyzed in fish tissues at both sites. Mean ?PFC concentration in fish plasma collected upstream the WWTP was 185ng/g w.w. compared to 545ng/g w.w. downstream the point of release. PFECHS was quantified for the first time in St. Lawrence River fish (mean plasma concentration in MWWE fish: 5.07±4.72ng/g w.w.). Results of transcriptomic responses were tissue-specific and indicated significant up-regulation for metallothionein (MT) in blood and MT, glutathion-S-transferase (GST), superoxide dismutase (SOD), and cytochromes P450 1A1 (CYP1A1) in gill tissue of fish collected in the MWWE suggesting greater stress responses for organisms at this location. Significant relationships were found between vitellogenin (Vtg) gene expression in liver, Vtg activity in plasma and perfluorotridecanoic acid (PFTrA), perfluorotetradecanoic acid (PFTeA), and perfluorodecane sulfonate (PFDS) plasma concentrations. The possible endocrine effects of these PFCs should be further investigated. PMID:23453599

Houde, Magali; Douville, Mélanie; Despatie, Simon-Pierre; De Silva, Amila O; Spencer, Christine

2013-08-01

152

Forecasting the major influences of predation and environment on cod recovery in the northern Gulf of St. Lawrence.  

PubMed

The northern Gulf of St. Lawrence (NGSL) stock of Atlantic cod (Gadus morhua), historically the second largest cod population in the Western Atlantic, has known a severe collapse during the early 1990 s and is currently considered as endangered by the Committee on the Status of Endangered Wildlife in Canada. As for many fish populations over the world which are currently being heavily exploited or overfished, urgent management actions in the form of recovery plans are needed for restoring this stock to sustainable levels. Stochastic projections based on a statistical population model incorporating predation were conducted over a period of 30 years (2010-2040) to assess the expected outcomes of alternative fishing strategies on the stock recovery under different scenarios of harp seal (Pagophilus groenlandicus) abundance and environmental conditions. This sensitivity study shows that water temperature is key in the rebuilding of the NGSL cod stock. Model projections suggest that maintaining the current management practice under cooler water temperatures is likely to maintain the species in an endangered status. Under current or warmer conditions in the Gulf of St. Lawrence, partial recovery might only be achieved by significant reductions in both fishing and predation pressure. In the medium-term, a management strategy that reduces catch could be favoured over a complete moratorium so as to minimize socio-economic impacts on the industry. PMID:24523852

Bousquet, Nicolas; Chassot, Emmanuel; Duplisea, Daniel E; Hammill, Mike O

2014-01-01

153

Forecasting the Major Influences of Predation and Environment on Cod Recovery in the Northern Gulf of St. Lawrence  

PubMed Central

The northern Gulf of St. Lawrence (NGSL) stock of Atlantic cod (Gadus morhua), historically the second largest cod population in the Western Atlantic, has known a severe collapse during the early 1990 s and is currently considered as endangered by the Committee on the Status of Endangered Wildlife in Canada. As for many fish populations over the world which are currently being heavily exploited or overfished, urgent management actions in the form of recovery plans are needed for restoring this stock to sustainable levels. Stochastic projections based on a statistical population model incorporating predation were conducted over a period of 30 years (2010–2040) to assess the expected outcomes of alternative fishing strategies on the stock recovery under different scenarios of harp seal (Pagophilus groenlandicus) abundance and environmental conditions. This sensitivity study shows that water temperature is key in the rebuilding of the NGSL cod stock. Model projections suggest that maintaining the current management practice under cooler water temperatures is likely to maintain the species in an endangered status. Under current or warmer conditions in the Gulf of St. Lawrence, partial recovery might only be achieved by significant reductions in both fishing and predation pressure. In the medium-term, a management strategy that reduces catch could be favoured over a complete moratorium so as to minimize socio-economic impacts on the industry. PMID:24523852

Bousquet, Nicolas; Chassot, Emmanuel; Duplisea, Daniel E.; Hammill, Mike O.

2014-01-01

154

ASSESSMENT OF WATER QUALITY USING EPIPHYTIC DIATOM ASSEMBLAGES ON CLADOPHORA FROM THE ST. LAWRENCE RIVER (CANADA)  

Microsoft Academic Search

Diatoms epiphytic on Cladophora were examined from 36 sites in the Saint Lawrence River between Salaberry-de-Valleyfield and Ile d'Orleans (Quábec, Canada). A total of 129 diatom taxa were identified from Cladophora in June 1995, and of these, 34 species were present at a relative abundance ? 1% at three or more sites. The four most abundant taxa were Cocconeis pediculus,

Jacqueline M. OConnell; Euan D. Reavie; John P. Smol

1997-01-01

155

Genetic Divergence among Northern Pike from Spawning Locations in the Upper St. Lawrence River  

Microsoft Academic Search

To assess the ecological consequences associated with the degradation of riparian wetlands that historically provided spawning and rearing habitat for northern pike Esox lucius, annual spawning migrations and genetic structure were used to examine this species' dependence on four specific spawning areas in the Thousand Islands region of the Saint Lawrence River. Tagging and recapture over three consecutive spawning seasons

Aaron Bosworth; John M. Farrell

2006-01-01

156

Comparative study of DNA adducts levels in white sucker fish (Catostomus commersoni) from the basin of the St. Lawrence River (Canada).  

PubMed

The levels of DNA adducts in the hepatic tissue of the white sucker fish species Catostomus commersoni were determined by 32P-postlabelling. The fish were caught at four sites: two sites near the city of Windsor (Québec, Canada) on the St. François River, a downstream tributary of the St. Lawrence River, and two sites in the St. Lawrence River itself, near the city of Montréal (Québec, Canada). The latter sites are known to be contaminated by many pollutants including polycyclic aromatic hydrocarbons. Total adduct levels in all fish ranged from 25.1-178.0 adducts per 10(9) nucleotides. White sucker from the selected sites of the St. Lawrence River had a significantly higher mean level of DNA adducts than those of the St. François River (129.4 vs 56.8, respectively). These results suggest that the effluents of many heavy industries (e.g. from a Soderberg aluminium plant) flowing in the St. Lawrence River are more likely to produce genotoxic damage to fish than those released in one of its tributary, and mainly associated to the activities of a small town and a nearby pulp and paper mill. PMID:8594417

el Adlouni, C; Tremblay, J; Walsh, P; Lagueux, J; Bureau, J; Laliberte, D; Keith, G; Nadeau, D; Poirier, G G

1995-07-19

157

Holocene environmental and parasequence development of the St. Jones Estuary, Delaware (USA): Foraminiferal proxies of natural climatic and anthropogenic change  

USGS Publications Warehouse

The benthic foraminiferal record of marshes located along western Delaware Bay (St. Jones Estuary, USA) reflects the response of estuaries to sea-level and paleoclimate change during the Holocene. System tracts are recognized and within them parasequences based on sedimentological and foraminiferal assemblages identification. The parasequences defined by foraminiferal assemblages appear correlative with rapid Holocene climate changes that are of worldwide significance: 6000-5000, 4200-3800, 3500-2500, 1200-1000, and 600??cal years BP. Following postglacial sea-level rise, modern subestuaries and marshes in the region began to develop between 6000 and 4000??years BP, depending on their proximity to the mouth of Delaware Bay and coastal geomorphology. Initial sediments were fluvial in origin, with freshwater marshes established around 4000??years BP. The subsequent sea-level transgression occurred sufficiently slowly that freshwater marshes alternated with salt marshes at the same sites to around 3000??years BP. Locally another two transgressions are identified at 1800 and 1000??years BP respectively. Marine influence increased in the estuaries until 600??years BP (Little Ice Age), when regression occurred. Sea-level began to rise again during the mid-19th Century at the end of the Little Ice Age, when marshes became established. The presence of a sand lens in the upper and middle estuary and the reduction in the number of tests in the top samples in cores from the same area also suggest an anthropogenic influence. The estuary infill resulted in a sharp transgressive sequence, represented by salt marsh foraminiferal assemblages in the upper part of the cores. The increase in marsh foraminifera in both areas suggests an increase in marine influence that might be due to the transgression beginning at the end of the Little Ice Age about 150-180??years ago coupled with anthropogenic straightening of the channel in 1913. ?? 2006 Elsevier B.V. All rights reserved.

Leorri, E.; Martin, R.; McLaughlin, P.

2006-01-01

158

Development of a Halotolerant Community in the St. Lucia Estuary (South Africa) during a Hypersaline Phase  

PubMed Central

Background The St. Lucia Estuary, Africa's largest estuarine lake, is currently experiencing unprecedented freshwater deprivation which has resulted in a northward gradient of drought effects, with hypersaline conditions in its northern lakes. Methodology/Principal Findings This study documents the changes that occurred in the biotic communities at False Bay from May 2010 to June 2011, in order to better understand ecosystem functioning in hypersaline habitats. Few zooplankton taxa were able to withstand the harsh environmental conditions during 2010. These were the flatworm Macrostomum sp., the harpacticoid copepod Cletocamptus confluens, the cyclopoid copepod Apocyclops cf. dengizicus and the ciliate Fabrea cf. salina. In addition to their exceptional salinity tolerance, they were involved in a remarkably simple food web. In June 2009, a bloom of an orange-pigmented cyanobacterium (Cyanothece sp.) was recorded in False Bay and persisted uninterruptedly for 18 months. Stable isotope analysis suggests that this cyanobacterium was the main prey item of F. cf. salina. This ciliate was then consumed by A. cf. dengizicus, which in turn was presumably consumed by flamingos as they flocked in the area when the copepods attained swarming densities. On the shore, cyanobacteria mats contributed to a population explosion of the staphylinid beetle Bledius pilicollis. Although zooplankton disappeared once salinities exceeded 130, many taxa are capable of producing spores or resting cysts to bridge harsh periods. The hypersaline community was disrupted by heavy summer rains in 2011, which alleviated drought conditions and resulted in a sharp increase in zooplankton stock and diversity. Conclusions/Significance Despite the current freshwater deprivation crisis, the False Bay region has shown to be resilient, harboring a unique biodiversity with species that are capable of enduring harsh environmental conditions. However, further freshwater deprivation may extend beyond the physiological thresholds of this community, as well as other unique biodiversity components which this system sustains. PMID:22238676

Carrasco, Nicola K.; Perissinotto, Renzo

2012-01-01

159

Nitrogen and phosphorus flux rates from sediment in the lower St. Johns River estuary.  

PubMed

Internal cycling of nutrients from the sediment and water column can be an important contribution to the total nutrient load of an aquatic ecosystem. Our objective was to estimate the internal nutrient loading of the Lower St. Johns River (LSJR). Dissolved reactive phosphorus (DRP) and ammonium (NH(4)-N) flux from sediments were measured under aerobic and anaerobic water column conditions using intact cores, to estimate the overall contribution of the sediments to P and N loading to the LSJR. The DRP flux under aerobic water column conditions averaged 0.13 mg m(-2) d(-1), approximately 37 times lower than that under anaerobic conditions (4.77 mg m(-2) d(-1)). The average NH(4)-N released from the anaerobic cores (18.03 mg m(-2) d(-1)) was also significantly greater than in the aerobic cores for all sites and seasons, indicating the strong relationship between nutrient fluxes and oxygen availability in the water column. The mean annual internal DRP load was estimated to be 330 metric tons (Mg) yr(-1), 21% of the total P load to the river, while the mean annual internal load of NH(4)-N was determined to be 2066 Mg yr(-1), 28% of the total N load to the LSJR estuary. As water resource managers reduce external loading to the LSJR the frequency of anaerobic events should decline, thereby reducing nutrient fluxes from the sediment to the water column, reducing the internal loading of DRP and NH(4)-N. Results from this study demonstrate that the internal flux of nutrients from sediments may be a significant portion of the total load and should be accounted for in the total nutrient budget of the river for successful restoration. PMID:15254137

Malecki, Lynette M; White, John R; Reddy, K R

2004-01-01

160

St. Johns Estuary: Estuarine Benthic Macroinvertebrates Phase 2 Final Report. Special Publication SJ2012-SP4.  

National Technical Information Service (NTIS)

Benthic macrofaunal communities can be strongly influenced by changes in freshwater inflows in an estuary. Macrofauna are affected by changes in estuarine condition (including nutrient concentrations, sediment supply and salinity) caused by variation in f...

J. B. Pollack, P. A. Montagna, T. A. Palmer

2011-01-01

161

Mesozoic fault reactivation along the St. Lawrence Rift System as constrained by (U-Th/He) thermochronology  

NASA Astrophysics Data System (ADS)

The Saint Lawrence Rift System (SLRS) is a half-graben, extending for 1000 km along St. Lawrence River valley. Late Proterozoic-Early Paleozoic faults of the graben form the contact with the metamorphic Grenvillian basement to the northwest and extend under the Paleozoic sedimentary sequences of the St. Lawrence Lowlands to the southeast. The SLRS is the second most seismically active area in Canada, but the causes of this activity remain unclear. Reactivation of the SLRS is believed to have occurred along Late Proterozoic to Early Paleozoic normal faults related to the opening of the Iapetus Ocean. The absence of strata younger than the Ordovician makes difficult to determine when the faults reactivated after the Ordovician. Field relations between the normal faults bordering the SLRS and those produced by the Charlevoix impact crater suggest a reactivation of the rift younger than the Devonian, the estimated age of the impact. Apatite (U-Th)/He thermochronology is an adequate tool to recognize thermal events related to fault movements. A thermochronology study was then started along three transects across the SLRS, from Québec up to Charlevoix. Apatites were extracted and separated from five granitic to charnockitic gneisses and an amphibolite of Grenvillian age. The samples were exposed on hanging wall and footwall of the Montmorency and Saint-Laurent faults at three different locations along the SLRS. For precision and accuracy, each of the six samples was analyzed for radiogenic 4He and U-Th contents at least twice. Apatite grains were isolated by heavy liquids and magnetic separation. For each sample, ten apatite grains were selected under optical microscope and inserted into Pt capsules. Particular care was taken to isolate apatite free of mineral and fluid inclusions. Indeed, SEM investigations showed that some inclusions are U-rich monazite, which is a supplementary source of 4He to be avoided. The 4He content was determined by using a static noble gas mass spectrometer in CRPG-Nancy and duplicates using a quadrupole mass spectrometer at GEOTOP-UQAM. 4He was measured against internal He gas standards and Durango apatite, with the reference U-Th/He age of 31.13 ± 1.01 Ma. U and Th contents were determined at CRPG-Nancy and duplicated at McGill University by ICP-MS. Preliminary results of U-Th/He on St.-Laurent fault yield an age of 137±12 Ma for the hanging wall, at Sault-au-Cochon and 118±10 Ma for a sample from the footwall, at Cap-aux-oies. Previous Apatite Fission Track (AFT) performed for the two locations gave expected older ages at 149±16 Ma and 196±19 Ma for the hanging wall and the footwall, respectively. These preliminary U-Th/He results are consistent with AFT ages of the area (i.e. as expected, U-Th/He ages are younger than AFT ages) but do not yet provide new constraints for the structural evolution of the St. Lawrence rift system. We are determining further U-Th/He ages and these ages will constrain an exhumation model of the region.

Bouvier, L.; Pinti, D. L.; Tremblay, A.; Minarik, W. G.; Roden-Tice, M. K.; Pik, R.

2011-12-01

162

Description of Gyrodactylus mediotorus n. sp. (Monogenea: Gyrodactylidae) infecting spottail shiner (Notropis hudsonius) from the St. Lawrence River, Canada.  

PubMed

Gyrodactylus mediotorus n. sp. is described from the body, fins, and buccal cavity of the spottail shiner, Notropis hudsonius (Cyprinidae) from the St. Lawrence River, Quebec, Canada. Gyrodactylus mediotorus n. sp. is the first species of Gyrodactylus Nordmann, 1832 described from N. hudsonius and is characterized by large hamuli, large medial process of the ventral bar, narrow linguiform ventral bar membrane, large anterolateral processes, and marginal hooks with long shafts and distinctly shaped sickle. The species that most resembles Gyrodactylus mediotorus n. sp. is Gyrodactylus protuberus Rogers and Wellborn, 1965 described from the stargazing shiner, Notropis uranoscopus Suttkus, 1959. The 2 species can be differentiated based on the larger hamuli (68.4 vs. 64) and ventral bar (38.4 vs. 24) of Gyrodactylus mediotorus n. sp. and the shape of the marginal hooks which for Gyrodactylus mediotorus n. sp. has a slightly larger toe and a point which is not as angled. The morphological description is supplemented with 436 sequenced base pairs of the 18S gene (including the V4 region) as well as 1,041 sequenced base pairs spanning the complete ITS-1, 5.8S, and ITS-2 regions. BLAST (Basic Local Alignment Search Tool) searches failed to provide any close matches for either regions of DNA, with Gyrodactylus colemanensis infecting Salvelinus fontinalis being the most genetically similar for both the 18S (?91%, JF836090) and ITS (?84%, JF836142) rDNA regions. Gyrodactylus mediotorus n. sp. has been found infecting spottail shiners in the St. Lawrence River in low prevalence and intensities periodically over the last 15 yr. PMID:23883192

King, Stanley D; Marcogliese, David J; Forest, Jonathon J H; McLaughlin, J Daniel; Bentzen, Paul

2013-12-01

163

Fossil brines preserved in the St-Lawrence Lowlands, Québec, Canada as revealed by their chemistry and noble gas isotopes  

NASA Astrophysics Data System (ADS)

Brines in Cambrian sandstones and Ordovician dolostones of the St-Lawrence Lowlands at Bécancour, Québec, Canada were sampled for analysis of all stable noble gases in order to trace their origin and migration path, in addition to quantifying their residence time. Major ion chemistry indicates that the brines are of Na-Ca-Cl type, possibly derived from halite dissolution. 87Sr/ 86Sr ratios and Ca excess indicate prolonged interactions with silicate rocks of the Proterozoic Grenville basement or the Cambrian Potsdam sandstone. The brines constrain a 2-3% contribution of mantle 3He and large amounts of nucleogenic 21Ne ? and 38Ar ? and radiogenic 4He and 40Ar ?. 4He/ 40Ar ? and 21Ne ?/ 40Ar ? ratios, corrected for mass fractionation during incomplete brine degassing, are identical to their production ratios in rocks. The source of salinity (halite dissolution), plus the occurrence of large amounts of 40Ar ? in brines constrain the residence time of Bécancour brines as being older than the Cretaceous. Evaporites in the St-Lawrence Lowlands likely existed only during Devonian-Silurian time. Brines might result from infiltration of Devonian water leaching halite, penetrating into or below the deeper Cambrian-Ordovician aquifers. During the Devonian, the basin reached temperatures higher than 250 °C, allowing for thermal maturation of local gas-prone source rocks (Utica shales) and possibly facilitating the release of radiogenic 40Ar ? into the brines. The last thermal event that could have facilitated the liberation of 40Ar ? into fluids and contributed to mantle 3He is the Cretaceous Monteregian Hills magmatic episode. For residence times younger than the Cretaceous, it is difficult to find an appropriate source of salinity and of nucleogenic/radiogenic gases to the Bécancour brines.

Pinti, Daniele L.; Béland-Otis, Catherine; Tremblay, Alain; Castro, Maria Clara; Hall, Chris M.; Marcil, Jean-Sébastien; Lavoie, Jean-Yves; Lapointe, Raynald

2011-08-01

164

Chlorinated hydrocarbons and mercury in sediments, red-winged blackbirds (Agelaius phoeniceus) and tree swallows (Tachycineta bicolor) from wetlands in the Great Lakes-St. Lawrence River basin  

Microsoft Academic Search

In 1991, the authors collected red-winged blackbird (Agelauis phoeniceus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings, and sediment samples from 2 wetland sites in the Great lakes and St. Lawrence River basin. They analyzed for chlorinated hydrocarbons and total mercury and found that biota contained contaminant concentrations which were one to two orders of magnitude above those in

Christine A. Bishop; Margie D. Koster; Andrew A. Chek; David J. T. Hussell; Ken Jock

1995-01-01

165

Health of Tree Swallow (Tachycineta Bicolor) Nestlings Exposed to Chlorinated Hydrocarbons in the St. Lawrence River Basin. Part I. Renal and Hepatic Vitamin A Concentrations  

Microsoft Academic Search

Sixteen-day-old tree swallows (Tachycineta bicolor), near fledging, were collected in 1999 and 2000 from nine sites representing a gradient of dioxin concentrations, within the vicinity of the St. Lawrence River in Canada and the United States, to determine if organochlorine contaminants correlated with vitamin A levels measured as retinol and retinyl palmitate. Mean concentrations of hepatic retinol ranged from 3mg

Barbara Martinovic; D. R. S Lean; Christine Bishop; Erinn Birmingham; Anne Secord; Ken Jock

2003-01-01

166

Endocrine and metabolic dysfunction in yellow perch, Perca flavescens, exposed to organic contaminants and heavy metals in the St. Lawrence River  

Microsoft Academic Search

The endocrine and biochemical responses to the acute stress of capture and handling were investigated in sexually mature and in immature male and female yellow perch, Perca flavescens, from a site contaminated by organic contaminants (PAHs and PCBs) and heavy metals (Hg, Cd, As, and Zn) and from a reference site in the St. Lawrence River. Following a standardized capture

Alice Hontela; D. Duclos; R. Fortin; P. Dumont

1995-01-01

167

ANALYSIS OF THE EFFECT OF PRINCIPAL STRESSES IN THE CHARLEVOIX, LOWER ST. LAWRENCE, NORTHERN APPALACHIAN, LAURENTIAN SLOPE AND GRAND BANKS REGIONS ON FAULTS IN NOVA  

E-print Network

). Analysis of focal mechanisms showed thrust-fault stress regime in the Gulf of St. Lawrence with three. Some of the Northern Appalachian's focal mechanisms show strike-slip stress regime. Between the Bay in the northeast. This study investigated published focal mechanism data for earthquakes from ~1970 to 2011

Beaumont, Christopher

168

Timing of Atlantic cod (Gadus morhua L.) seasonal migrations in the southern Gulf of St Lawrence: interannual variability and proximate control  

Microsoft Academic Search

Comeau, L. A., Campana, S. E., and Chouinard, G. A. 2002. Timing of Atlantic cod (Gadus morhua L.) seasonal migrations in the southern Gulf of St Lawrence: interannual variability and proximate control. - ICES Journal of Marine Science, 59: 333-351. The objective of this study was to identify likely proximate cues to the seasonal migrations of cod, Gadus morhua L.,

L. A. Comeau; S. E. Campana; G. A. Chouinard

2002-01-01

169

A processing plant survey of external lesions of American eels ( Anguilla rostrata) from Lake Ontario and the St. Lawrence River, Canada  

Microsoft Academic Search

Signs of decreasing landing and recruitment were observed in the last decade in American eels (Anguilla rostrata) from the St. Lawrence River basin, Canada. In order to verify if the declines were associated with high prevalence of diseases among commercial catches, a total of 12243 eels captured in five commercial fishing sites were inspected at two processing plants in 1992.

Lucie T Dutil; Catherine M Couillard; Denise Bélanger

1997-01-01

170

Contrasting shell\\/tissue characteristics of Dreissena polymorpha and Dreissena bugensis in relation to environmental heterogeneity in the St. Lawrence River  

Microsoft Academic Search

The zebra mussel, Dreissena polymorpha, is widespread in the St. Lawrence River while the conspecific quagga mussel, Dreissena bugensis, is found only in the Lake Ontario outflow region of the river. This situation provided an opportunity to evaluate in situ environmental and interspecific heterogeneity in shell and tissue growth. Shell dry weight, carbon content, and shell strength of D. polymorpha

Andrew F. Casper; Ladd E. Johnson

2010-01-01

171

A telephone survey of eel fishermen regarding external lesions and mortalities of American eels ( Anguilla rostrata) from Lake Ontario and the St. Lawrence River basin, Canada  

Microsoft Academic Search

Signs of decreasing landings and recruitment have been observed during the last decade in American eels (Anguilla rostrata) from the St. Lawrence River basin, Canada. A study was undertaken to examine whether important manifestational diseases among commercial catches could be associated with these declines. During this survey, 56 fishermen from Lakes Ontario, Saint-François and Saint-Pierre, the Richelieu River, the Québec

Lucie Dutil; Denise Bélanger; Catherine M Couillard

1997-01-01

172

Environmental Contamination and Human Exposure Assessment to Manganese in the St-Lawrence River Ecozone (Quebec, Canada) Using an Environmental Fate\\/Exposure Model: GEOTOX  

Microsoft Academic Search

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic derivative of manganese (Mn) used as an additive in unleaded gasoline. The combustion of MMT leads to the formation of oxides of manganese. The objective of the present study is to predict the environmental levels of Mn and the human exposure in the St-Lawrence ecozone (fluvial section, Quebec, Canada) using an environmental fate\\/exposure

S. Loranger; J. Zayed

1997-01-01

173

Effects of zebra mussels, obtained from Lake Erie and St Lawrence River, as a food source on immune system of lesser scaup  

SciTech Connect

A feeding study was undertaken to assess the influence of a zebra mussel diet from Lake Erie and the St.Lawrence river on the immune system of lesser scaup. The Great lakes and the St.Lawrence river are known to be among the most contaminated waters found in the country. Analytical studies have shown that zebra mussels are contaminated by organochlorines and other pollutants. The occurrence of these toxicants in the food diet of lesser scaup can cause serious injuries. The immune system, in its capacity to destroy foreign particles and protect the host against diseases, can serve as a useful sentinel of the health status of these environmentally stressed organisms. Immune parameters of lesser scaup fed with zebra mussels from Lake Erie or the St. Lawrence river were evaluated. The duration of the feeding trial was nine weeks. Phagocytic activity and oxidative bursts of heterophils were evaluated by flow cytometry. Intracellular thiol levels of lymphocytes and heterophils were also determined by flow cytometry. The results showed a dimunition of phagocytic activity and bactericidal potential after 6 weeks of the zebra mussel diet compared to the control. These results may be associated with pathology problems encountered in treated groups at the end of the diet. Birds from the St. Lawrence River group (40%) and the Lake Erie group (40%) demonstrated variable degrees of pododermatitis compared to the control group. The intracellular level of thiol was consistently found to be elevated in lymphocytes and heterophyls from birds feeding with on the St. Lawrence River. In conclusion, flow cytometry assays like phagocytosis, oxidative burst and thiol staining can serve as biomarkers of the immune status of birds and can give important information for evaluating the health of birds exposed to environmental contamination.

Flipo, D.; Fournier, M. [Univ. du Quebec, Montreal, Quebec (Canada); Beaulieu, C.; Tessier, C. [McGill Univ., Montreal, Quebec (Canada)

1995-12-31

174

Superfund record of decision (EPA Region 2): General Motors/Central Foundry Division Site, St. Lawrence County, Massena, NY. (Second remedial action), March 1992. Final report  

SciTech Connect

The 270-acre General Motors/Central Foundry Division site is an aluminum casting plant in Massena, St. Lawrence County, New York. From 1985 to 1989, General Motors investigations detected contamination in soil, sludge, debris, sediment, ground water and surface water. In 1988, an interim cap was placed over the industrial landfill. A 1990 ROD addressed most affected areas of the site, including the St. Lawrence River System sediments, contaminated ground water, soils on the facility and the St. Regis Mohawk Indian Reservation, and material at four lagoons and the North Disposal Area. The ROD provides the final remedy for the contaminated soil, sludge, debris, and groundwater at the East Disposal Area and the Industrial Lagoon. The primary contaminants of concern are VOCs, including TCE; and other organics, including PCBs, phenols, and PAHs. The selected remedial action for the site are included.

Not Available

1992-03-31

175

Crocodiles count on it: Regulation of discharge to Lake St Lucia Estuary by a South African peatland  

NASA Astrophysics Data System (ADS)

The Mfabeni mire is located within the iSimangaliso Wetland Park in north-eastern KwaZulu-Natal Province on the Indian Ocean sea-board of South Africa. This mire complex includes open peatland with occurrences of sedge communities, Sphagnum (rare in South Africa), and swamp forest which is common in the region (but rare in South Africa). It is one of the largest (1650 ha), thickest (10.8 m of peat) and the oldest (~45,000 years Before Present) known peatlands in South Africa. The mire is almost pristine, with very few disturbances. In the past the surrounding area supported pine plantations but these alien trees were recently removed, with conservation and tourism the primary designated activities. Surface and groundwater exchanges to and within the mire and its surrounding coastal dune landscape were studied. Profiles of electrical conductivity and major cations and anions, as well as natural isotopes (?2H and ?18O) in water samples of ground and surface water were also analysed to develop a conceptual model of the system’s hydrological function. Water efflux from an inland dune complex provides substantial recharge towards Mfabeni, while coastward hydraulic gradients from the dune complex through the wetland are evident. Consequently, the linkages between the dune system and Mfabeni, and the peatland’s water regulation function, dictate the nature and magnitude of the local freshwater discharge to the estuary, and internal water exchanges that control peatland ecological function. The hydrograph from the stream outlet indicate an initial rapid response in increased flows after major rainfall events but with a delayed drawdown over time reflecting the contribution of the relatively large size of the mire (comprising 38% of the catchment) in attenuating flood events and ensuring sustained flow to the estuary. Freshwater discharge from the Mfabeni mire to the St. Lucia estuary, which has provided refuge for aquatic species during periods of drought, may become crucial under a more erratic climate.

Price, J. S.; Grundling, P.; Grootjans, A.

2010-12-01

176

Fish community changes in the St. Louis River estuary, Lake Superior, 1989-1996: Is it ruffe or population dynamics?  

USGS Publications Warehouse

Ruffe (Gymnocephalus cernuus) have been implicated in density declines of native species through egg predation and competition for food in some European waters where they were introduced. Density estimates for ruffe and principal native fishes in the St. Louis River estuary (western Lake Superior) were developed for 1989 to 1996 to measure changes in the fish community in response to an unintentional introduction of ruffe. During the study, ruffe density increased and the densities of several native species decreased. The reductions of native stocks to the natural population dynamics of the same species from Chequamegon Bay, Lake Superior (an area with very few ruffe) were developed, where there was a 24-year record of density. Using these data, short- and long-term variations in catch and correlations among species within years were compared, and species-specific distributions were developed of observed trends in abundance of native fishes in Chequamegon Bay indexed by the slopes of densities across years. From these distributions and our observed trend-line slopes from the St. Louis River, probabilities of measuring negative change at the magnitude observed in the St. Louis River were estimated. Compared with trends in Chequamegon Bay, there was a high probability of obtaining the negative slopes measured for most species, which suggests natural population dynamics could explain, the declines rather than interactions with ruffe. Variable recruitment, which was not related to ruffe density, and associated density-dependent changes in mortality likely were responsible for density declines of native species.

Bronte, Charles R.; Evrard, Lori M.; Brown, William P.; Mayo, Kathleen R.; Edwards, Andrew J.

1998-01-01

177

Neoplastic and nonneoplastic hepatic changes in lake whitefish (Coregonus clupeaformis) from the St. Lawrence River, Quebec, Canada.  

PubMed

As part of a survey of fish diseases, lake whitefish (Coregonus clupeaformis) were collected in fall 1995 from the St. Lawrence River 15 km upstream of Quebec City, Quebec, Canada, to assess the prevalence of liver lesions. A total of 141 fish were captured and necropsied, and three standard sections of liver were taken for histological examination. Prevalences of altered hepatocyte foci, hepatocellular carcinoma, cholangioma, and cholangiocarcinoma were 0.7%, 2.1%, 0.7%, and 2.1%, respectively. Thus, the overall prevalence of liver neoplasia was 4.9% (7/141). Hepatic tumors were only observed in fish 7 years old or older. Fish age was significantly and positively correlated with the index assessing the number and size of macrophage aggregates (p<0.001; rs = 0.16). Hepatocyte vacuolation, anisokaryosis, lymphocytic infiltration, and bile duct hyperplasia were also observed but were not related to the age, length, sex, or condition factor of the fish. These results represent the first report on a series of hepatic tumors in a wild salmonid species. PMID:9485481

Mikaelian, I; de Lafontaine, Y; Menard, C; Tellier, P; Harshbarger, J; Martineau, D

1998-04-01

178

Myxozoan communities parasitizing Notropis hudsonius (Cyprinidae) at selected localities on the St. Lawrence River, Quebec: possible effects of urban effluents.  

PubMed

Late summer myxozoan infra- and component communities parasitizing 73 Notropis hudsonius at 5 sites on the St. Lawrence River upstream and downstream from the island of Montreal are described from study of histological sections of individual fish. Community membership included Myxobolus sp. A (intracellular in striated muscle fibers), Myxobolus sp. B (intracellular in striated muscle fibers), Myxobolus sp. C (brain), and Thelohanellus notatus (Mavor, 1916) Kudo, 1929 (loose connective tissue), all of which are histozoic myxobolids displaying strict tissue specificity for trophozoite development. Mean infracommunity richness in fish at the separate localities was estimated to be 0.4 +/- 0.5 to 1.3 +/- 0.7, with a maximum richness of 3 in any 1 fish. Component community richness in host samples was 2 to 4. It is argued that these are relatively high levels of diversity for freshwater fish parasites but that the values are probably conservative because of the study of only portions of individual fish. The percentage of fish infected with myxozoans of any species and infracommunity richness was significantly greater below the island of Montreal compared with above it. It is suspected that increased oligochaete populations at these sites, resulting from sewage-caused organic enrichment of sediments, may have accounted for the observed increased prevalence of infection. PMID:11695414

Marcogliese, D J; Cone, D K

2001-10-01

179

The Corossol structure: A possible impact crater on the seafloor of the northwestern Gulf of St. Lawrence, Eastern Canada  

NASA Astrophysics Data System (ADS)

We report on a 4.1 (±0.2) km diameter and 185 m deep circular submarine structure exposed on the seabed in >40 m water depths in the northwestern Gulf of St. Lawrence (Eastern Canada) from the analysis of high-resolution multibeam bathymetric and seismic data. The presence of a circular form characterized by a central uplift and concentric rings resembles the morphology and geometry of complex meteorite impact structures. Also, other origins, such as kimberlites, intrusions, karsts, or diapirs, can be eliminated on geological criteria. A single 4 cm long breccia fragment recovered from the central uplift has numerous glassy droplets of fluorapatite composition, assumed to be impact melts, and a single quartz grain with planar intersection features thought to be shock-induced planar deformation features (PDFs). The absolute age of this possible impact structure is unknown, but its geological setting indicates that it was formed long after the Mid-Ordovician and before regional pre-Quaternary sea-level lowstands. Present results outline the need for further examination to confirm an impact origin and to precisely date the formation of the structure.

Lajeunesse, Patrick; St-Onge, Guillaume; Locat, Jacques; Duchesne, Mathieu J.; Higgins, Michael D.; Sanfaçon, Richard; Ortiz, Joseph

2013-12-01

180

Estimation, analysis, sources, and verification of consumptive water use data in the Great Lakes-St. Lawrence River basin  

USGS Publications Warehouse

The Great Lakes-St. Lawrence River basin provides water for many uses and for wildlife habitat; thus many groups have developed strategies to manage the basin 's water resource. The International Joint Commission (IJC) is reviewing and comparing available consumptive-use data to assess the magnitude and effect of consumptive uses under present projected economic and hydraulic conditions on lake levels. As a part of this effort, the U.S. Geological Survey compared its own estimates of consumptive use in the United States with those generated by (1) the International Great Lakes Diversions and (2) the IJC. The U.S. Geological Survey also developed two methods of calculating consumptive-use projections for 1980 through 2000; one method yields an estimate of 6,490 cu ft/s for the year 2000; the other yields an estimate of 8,330 cu ft/s. These two projections could be considered the upper and lower limits for the year 2000. The reasons for the varying estimates are differences in (1) methods by which base year values were developed, and (2) the methods or models that were used to project consumptive-use values for the future. Acquisition of consumptive-use data from water users or governmental agencies or ministries would be desirable to minimize reliance on estimates. (USGS)

Snavely, D.S.

1988-01-01

181

Steady-state mass balance model for mercury in the St. Lawrence River near Cornwall, Ontario, Canada.  

PubMed

We have developed a local mass balance model for the St. Lawrence River near Cornwall, Ontario that describes the fate and transport of mercury in three forms, elemental, divalent, and methylated, in a five compartment environment (air, water, sediments, periphyton, and benthos). Our objective was to construct a steady-state mass balance model to determine the dominant sources and sinks of mercury in this environment. We compiled mercury concentrations, fluxes, and transformation rates from previous studies completed in this section of the river to develop the model. The inflow of mercury was the major source to this system, accounting for 0.42 mol month(-1), or 95.5% of all mercury inputs, whereas outflow was 0.28 mol month(-1), or 63.6% of all losses, and sediment deposition was 0.12 mol month(-1), or 27.3% of all losses. Uncertainty estimates were greatest for advective fluxes in surface water, porewater, periphyton, and benthic invertebrates. PMID:23287073

Lessard, Charlotte R; Poulain, Alexandre J; Ridal, Jeffrey J; Blais, Jules M

2013-03-01

182

Shipping noise in whale habitat: characteristics, sources, budget, and impact on belugas in Saguenay-St. Lawrence Marine Park hub.  

PubMed

A continuous car ferry line crossing the Saguenay Fjord mouth and traffic from the local whale-watching fleet introduce high levels of shipping noise in the heart of the Saguenay-St. Lawrence Marine Park. To characterize this noise and examine its potential impact on belugas, a 4-hydrophone array was deployed in the area and continuously recorded for five weeks in May-June 2009. The source levels of the different vessel types showed little dependence on vessel size or speed increase. Their spectral range covered 33 dB. Lowest noise levels occurred at night, when ferry crossing pace was reduced, and daytime noise peaked during whale-watching tour departures and arrivals. Natural ambient noise prevailed 9.4% of the time. Ferry traffic added 30-35 dB to ambient levels above 1 kHz during crossings, which contributed 8 to 14 dB to hourly averages. The whale-watching fleet added up to 5.6 dB during peak hours. Assuming no behavioral or auditory compensation, half of the time, beluga potential communication range was reduced to less than ~30% of its expected value under natural noise conditions, and to less than ~15% for one quarter of the time, with little dependence on call frequency. The echolocation band for this population of belugas was also affected by the shipping noise. PMID:22779457

Gervaise, Cédric; Simard, Yvan; Roy, Nathalie; Kinda, Bazile; Ménard, Nadia

2012-07-01

183

Passive acoustic detection and localization of whales: effects of shipping noise in Saguenay-St. Lawrence Marine Park.  

PubMed

The performance of large-aperture hydrophone arrays to detect and localize blue and fin whales' 15-85 Hz signature vocalizations under ocean noise conditions was assessed through simulations from a normal mode propagation model combined to noise statistics from 15 960 h of recordings in Saguenay-St. Lawrence Marine Park. The probability density functions of 2482 summer noise level estimates in the call bands were used to attach a probability of detection/masking to the simulated call levels as a function of whale depth and range for typical environmental conditions. Results indicate that call detection was modulated by the calling depth relative to the sound channel axis and by modal constructive and destructive interferences with range. Masking of loud infrasounds could reach 40% at 30 km for a receiver at the optimal depth. The 30 dB weaker blue whale D-call were subject to severe masking. Mapping the percentages of detection and localization allowed assessing the performance of a six-hydrophone array under mean- and low-noise conditions. This approach is helpful for optimizing hydrophone configuration in implementing passive acoustic monitoring arrays and building their detection function for whale density assessment, as an alternative to or in combination with the traditional undersampling visual methods. PMID:18537362

Simard, Yvan; Roy, Nathalie; Gervaise, Cédric

2008-06-01

184

Spatial and Temporal Trends of Mercury Concentrations in Young-of-the-Year Spottail Shiners ( Notropis hudsonius ) in the St. Lawrence River at Cornwall, ON  

Microsoft Academic Search

The St. Lawrence River at Cornwall, Ontario is an “Area of Concern” because of mercury (Hg) biomagnification from bottom sediments.\\u000a To assess the spatial and temporal distribution of Hg in the food web, young-of-the-year (YOY) spottail shiners (Notropis hudsonius) were collected in August 2005 from five sites along the Cornwall waterfront within a Hg-contaminated zone and two reference\\u000a zones. The

Emily S. Choy; Peter V. Hodson; Linda M. Campbell; Adrienne R. Fowlie; Jeff Ridal

2008-01-01

185

Invasive species are less parasitized than native competitors, but for how long? The case of the round goby in the Great Lakes-St. Lawrence Basin  

Microsoft Academic Search

There is increasing evidence that parasitism represents an unpredictable dimension of the ecological impacts of biological\\u000a invasions. In addition to the risk of exotic pathogen transmission, other mechanisms such as parasite-release, could contribute\\u000a to shaping the relationship between introduced species and native communities. In this study, we used the Eurasian round goby\\u000a (Neogobius menalostomus) in the Great Lakes-St. Lawrence River

Andrée D. Gendron; David J. Marcogliese; Michael Thomas

186

Meltwater discharge and the triggering of Younger Dryas : new data on the chronology of Champlain Sea transgression in the St-Lawrence River Valley  

Microsoft Academic Search

Accurate chronology of ice retreat is crucial to understand the Ocean-Atmosphere couple at the end of the Pleistocene. The St-Lawrence River Valley is key in this regard, and two sedimentary sequences from Mount Saint-Hilaire, in the middle of the valley, contain a record that sheds new lignt on ice retreat and the penecontemporaneous proglacial marine invasion. Basal AMS-dates on terrestrial

P. Richard; S. Occhietti

2004-01-01

187

Variations in water temperatures and levels in the St. Lawrence River (Québec, Canada) and potential implications for three common fish species  

Microsoft Academic Search

The implications for fish populations of long- (multi-decadal, 1919–2007), medium- (inter-annual) and short- (seasonal, daily)\\u000a term variations in water temperatures and levels were examined in the St. Lawrence River (SLR). The effects of the seasonal\\u000a thermal regime of the SLR and its tributaries on the thermal budgets of resident and migrating fish were contrasted. Over\\u000a the 1919–2007 period, the mean

Christiane Hudon; Alain Armellin; Pierre Gagnon; Alain Patoine

2010-01-01

188

Recent ecological trends in lower trophic levels of the international section of the St. Lawrence River: a comparison of the 1970s to the 2000s  

Microsoft Academic Search

Changes from the 1970s to 2000s in phosphorus and chlorophyll levels, water transparency, zooplankton, and benthic communities\\u000a in the upper, International Section of the St. Lawrence River were evaluated using trend data from limnological surveys. The\\u000a influence of Lake Ontario as a source for riverine production was evident in the upper river. Total phosphorus levels from\\u000a 1976 to 1978 (average

J. M. Farrell; K. T. Holeck; E. L. Mills; C. E. Hoffman; V. J. Patil

2010-01-01

189

Intra- and inter-species differences in persistent organic contaminants in the blubber of blue whales and humpback whales from the Gulf of St. Lawrence, Canada  

Microsoft Academic Search

Biopsy samples of blubber from adult male and female blue whales, and from female and young-of-the-year humpback whales were collected during the summers of 1992–1999 in the Gulf of St. Lawrence, Canada. In blue whales, concentrations of 25 PCB congeners, DDT and metabolites and several other organochlorine compounds were present at higher concentrations in the blubber of males relative to

Chris Metcalfe; Brenda Koenig; Tracy Metcalfe; Gordon Paterson; Richard Sears

2004-01-01

190

Southeast Atlantic coast estuaries, Sapelo Sound to St. Simons Sound. Georgia: circulation survey, 1980  

SciTech Connect

The purpose of the report is to inform potential users of the data collected during the National Ocean Service (NOS) 1980 circulation survey in the Georgia estuaries. The report presents information on station locations, periods of occupation, instruments, sampling rate, data quality, and processing procedures. The measurement of atmospheric parameters is necessary for the study of nontidal water movement caused by winds and changing atmospheric pressure. Another benefit derived from current data collected is as an aid in the prediction of oil-spill and pollutant transport.

Watson, W.A.

1984-01-01

191

Georgia Estuaries Circulation Survey  

Microsoft Academic Search

The 1980 Circulation Survey, Southeast Atlantic Coast Estuaries, Sapelo Sound to St. Andrew Sound, Georgia, was conducted from March through June 1980 by the National Oceanic and Atmospheric Administration's Ship FERREL. Sapelo Sound, Doboy Sound, Altamaha Sound, St. Simons Sound, and their tributaries (collectively referred to as Georgia Estuaries) were studied. Current, tide, meteorological, and conductivity-temperature\\/depth data were collected. These

S. McCoy; W. Watson

1983-01-01

192

Importance of mesozooplankton feeding for the downward flux of biogenic carbon in the Gulf of St. Lawrence (Canada)  

NASA Astrophysics Data System (ADS)

We tested the importance of mesozooplankton feeding and defecation for the downward flux of biogenic carbon (C) in the Gulf of St. Lawrence, a marine coastal environment characterized by high zooplankton abundance. Five stations were sampled over nine cruises between July 1992 and June 1994. The rates of chlorophyll (Chl) ingestion and C defecation were determined for the major copepod species. Free-drifting, short-term (24 h) sediment traps were deployed at the sampled sites at 50 and 150 m, and the trap contents were analyzed for fecal pellets (microscopy), Chl and pheopigments (chromatography). The flux at 50 m of C associated with fecal pellets ranged between 5 and 138 mg C m -2 d -1, while total POC flux varied between 78 and 302 mg C m -2 d -1. Of the total POC found in sediment traps at 50 m, close to 50%, on average, was composed of zooplankton fecal pellets. In contrast, direct algal (Chl) sinking was <10%. The fecal pellet contribution varied seasonally, with a maximum (>73%) in June 1994 at all stations. This maximum did not necessarily coincide with the highest rate of production of fecal pellets in the surface waters, indicating that other factors influenced the sinking of fecal pellets. A shallow mixed-layer depth seemed to favor fast removal from the surface. The average fecal pellet contribution to the total downward POC flux was slightly higher for stations 4 and 5 (52% compared with 39% for the other stations). These stations were characterized by zooplankton communities that differed from those of the other stations, smaller copepods such as Temora longicornis frequently dominated at stations 4 and 5, Calanus spp. dominated at stations 1, 2 and 6. High fluxes of fecal pellets frequently occurred when the index of herbivory (Chl ingestion : total C ingestion) was low, transferring downwards carbon of heterotrophic origin. The contribution of C-transformed pheopigments to total POC flux was low (6% on average). It co-varied with the degree of herbivory in the overlying waters. The production of fecal pellets in the top 50 m co-varied with Chl ingestion, but not with the index of herbivory, consistent with an algal food intake representing <50% of total C ingested. Phytoplankton ingestion was highest when primary production (not algal biomass) was maximum. In consequence, mesozooplankton feeding did not exert a strong control over the phytoplankton biomass of the Gulf of St. Lawrence (at most 10%), but it was more closely tied to primary production. Phytoplankton biomass is more likely controlled by physical factors in this region. Mesozooplankton fecal pellets contributed significantly to the downward flux of biogenic C all through the year in this environment, transferring alternatively C of autotrophic and heterotrophic origin.

Roy, S.; Silverberg, N.; Romero, N.; Deibel, D.; Klein, B.; Savenkoff, C.; Vézina, A.; Tremblay, J.-É.; Legendre, L.; Rivkin, R. B.

2000-04-01

193

Evaluation of liver histopathology and EROD activity in St. Lawrence lake sturgeon (Acipenser fulvescens) in comparison with a reference population  

SciTech Connect

In an attempt to evaluate the effects of contaminants on the lake sturgeon Acipenser fulvescens, fish were netted from two sites: Riviere des Prairies, confluent with the St. Lawrence River near Montreal, and a reference site on the upper reaches of the Ottawa River in the La Verendrye Park. Livers of fish collected from the Riviere des Prairies were difficult to homogenize, and they left behind strands of what appeared to be connective tissue. Suspecting hepatic fibrosis, the authors decided to evaluate the livers for histopathologic changes. Nineteen adult lake sturgeon (eleven male and eight female) were examined. Following fixation, routine processing, sectioning, and staining with hematoxylin and eosin, microscopic evaluation revealed the following: Sections taken from livers of fish from the Riviere des Prairies site showed excessive fat accumulation and often severe chronic-active cholangiohepatitis. Bile duct proliferation (p < 0.0001), periportal fibrosis (p < 0.0001), inflammation (p < 0.001), and fat accumulation (p < 0.05) were more pronounced in the fish from the Riviere des Prairies site. Melano-macrophage centers appeared to be both paler and gave the appearance of fewer numbers (p < 0.01). Livers from lake sturgeon taken from the reference site had a more normal appearance. The EROD levels were also significantly induced in these fish (reference 3.39 {+-} 0.57; Riviere des Prairies site 8.21 {+-} 0.87 pmol/mg protein/min; p < 0.0005). The EROD levels positively correlated with bile duct proliferation (r{sup 2} = 0.44; p = 0.001) and periportal fibrosis (r{sup 2} = 0.41; p = 0.002). Despite the statistical associations above, the authors cannot categorically state that contaminants are the sole cause of the lesions seen.

Rousseaux, C.G. [Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada)]|[GlobalTox International Consultants, Inc., Ottawa, Ontario (Canada)]|[Univ. of Quebec, Montreal, Quebec (Canada); Branchaud, A.; Spear, P.A. [Univ. of Quebec, Montreal, Quebec (Canada)

1995-05-01

194

Hazard assessment of a simulated oil spill on intertidal areas of the St. Lawrence River with SPMD-TOX  

USGS Publications Warehouse

Phytoremediation in a simulated crude oil spill was studied with a "minimalistic" approach. The SPMD-TOX paradigm - a miniature passive sorptive device to collect and concentrate chemicals and microscale tests to detect toxicity - was used to monitor over time the bioavailability and potential toxicity of an oil spill. A simulated crude oil spill was initiated on an intertidal freshwater grass-wetland along the St. Lawrence River southwest of Quebec City, Quebec, Canada. Several phytoremediation treatments were investigated; to dissipate and ameliorate the spill, treatments included nutrient amendments with inorganic nitrogen sources (ammonium nitrate and sodium nitrate) and phosphate (super triple phosphate) with and without cut plants, with natural attenuation (no phytoremedial treatment) as a control. Sequestered oil residues were bioavailable in all oil-treated plots in Weeks 1 and 2. Interestingly, the samples were colored and fluoresced under ultraviolet light. In addition, microscale tests showed that sequestered residues were acutely toxic and genotoxic, as well as that they induced hepatic P450 enzymes. Analysis of these data suggested that polycyclic aromatic hydrocarbons were among the bioavailable residues sequestered. In addition, these findings suggested that the toxic bioavailable fractions of the oil spill and degradation products dissipated rapidly over time because after the second week the water column contained no oil or detectable degradation products in this riverine intertidal wetland. SPMD-TOX revealed no evidence of bioavailable oil products in Weeks 4, 6, 8, and 12. All phytoremediation efforts appeared to be ineffective in changing either the dissipation rate or the ability to ameliorate the oil toxicity. SPMD-TOX analysis of the water columns from these riverine experimental plots profiled the occurrence, dissipation, and influence of phytoremediation on the bioavailability and toxicity of oil products (parent or degradation products. ?? 2004 Wiley Periodicals, Inc.

Johnson, B.T.; Petty, J.D.; Huckins, J.N.; Lee, K.; Gauthier, J.

2004-01-01

195

Hazard assessment of a simulated oil spill on intertidal areas of the St. Lawrence River with SPMD-TOX.  

PubMed

Phytoremediation in a simulated crude oil spill was studied with a "minimalistic" approach. The SPMD-TOX paradigm-a miniature passive sorptive device to collect and concentrate chemicals and microscale tests to detect toxicity-was used to monitor over time the bioavailability and potential toxicity of an oil spill. A simulated crude oil spill was initiated on an intertidal freshwater grass-wetland along the St. Lawrence River southwest of Quebec City, Quebec, Canada. Several phytoremediation treatments were investigated; to dissipate and ameliorate the spill, treatments included nutrient amendments with inorganic nitrogen sources (ammonium nitrate and sodium nitrate) and phosphate (super triple phosphate) with and without cut plants, with natural attenuation (no phytoremedial treatment) as a control. Sequestered oil residues were bioavailable in all oil-treated plots in Weeks 1 and 2. Interestingly, the samples were colored and fluoresced under ultraviolet light. In addition, microscale tests showed that sequestered residues were acutely toxic and genotoxic, as well as that they induced hepatic P(450) enzymes. Analysis of these data suggested that polycyclic aromatic hydrocarbons were among the bioavailable residues sequestered. In addition, these findings suggested that the toxic bioavailable fractions of the oil spill and degradation products dissipated rapidly over time because after the second week the water column contained no oil or detectable degradation products in this riverine intertidal wetland. SPMD-TOX revealed no evidence of bioavailable oil products in Weeks 4, 6, 8, and 12. All phytoremediation efforts appeared to be ineffective in changing either the dissipation rate or the ability to ameliorate the oil toxicity. SPMD-TOX analysis of the water columns from these riverine experimental plots profiled the occurrence, dissipation, and influence of phytoremediation on the bioavailability and toxicity of oil products (parent or degradation products). PMID:15269903

Johnson, B Thomas; Petty, James D; Huckins, James N; Lee, Ken; Gauthier, Joanne

2004-08-01

196

Macrofossil Record of a Middle Holocene Drop in Relative Sea Level at the St. Lawrence Estuary, Québec  

NASA Astrophysics Data System (ADS)

Macrofossil analysis of a peat layer overlying shallow-water estuarine sediments allows the reconstruction of vegetation changes between 7000 and 6000 14C yr B.P. near Montmagny, Québec. About 7500-7000 14C yr B.P., the study site was brackish and intertidal. Next, a cattail marsh dominated by Typha changed into a terrestrial fire-prone environment that contained xero-mesophilous tree species ( Pinus/ Tsuga) and lasted a few hundred years, until about 6800 14C yr B.P. This rapid change may have resulted from land tilting associated with the northward migration of the postglacial forebulge. An abrupt change from a Pinus/ Tsuga-dominated cover to shrubby vegetation was due to a fire that affected the site 6800 14C yr B.P. Fossil mosses at the site reflect local wetness likely produced by a rise in the water table starting about 6600 14C yr B.P. By 6500-6400 14C yr B.P., seawater returned and freshwater plants were replaced by semihalophilous and halophilous plants. Thinning of annual rings in fossil larch reflects this change from a terrestrial peatland to a treeless coast.

Bhiry, Najat; Garneau, Michelle; Filion, Louise

2000-09-01

197

Identification and dating of a key Late Pleistocene stratigraphic unit in the St. Lawrence Estuary and Gulf (Eastern Canada)  

E-print Network

-advances or stillstands of the Laurentide Ice Sheet margins in the Goldthwait Sea that began at or before the Younger-Onge et al., 2003) during the late deglacia- tion as the Laurentide Ice Sheet was retreating rapidly

198

St. Lawrence Cattaraugus  

E-print Network

Grove Bolivar Willing Ward Alfred Birdsall Burns Andover Angelica Genesee Rushford Wellsville Granger Napoli Ischua MachiasDayton Olean Red House Freedom Lyndon Hinsdale Franklinville Portville Mansfield

Keinan, Alon

199

46 CFR 401.405 - Basic rates and charges on the St. Lawrence River and Lake Ontario.  

...Lawrence River and Lake Ontario. 401.405 Section 401.405 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE REGULATIONS Rates, Charges, and Conditions for Pilotage Services §...

2014-10-01

200

A comparison of biofilms from macrophytes and rocks for taste and odour producers in the St. Lawrence river.  

PubMed

Given their widespread and prolific annual development in the St. Lawrence River (SLR), macrophytes (i.e. submerged aquatic plants) represent large surface areas for biofilm growth and potentially important sites for associated production of taste and odour (T&O) compounds. We therefore evaluated the importance of submerged macrophytes and their associated biofilms for production of T&O compounds, 2-methylisoborneol (MIB) and geosmin (GM), compared with biofilms from adjacent rocks. We also tested the hypothesis that production of these compounds would differ between macrophyte species, based on the premise that they are not inert substrates but directly influence the communities that colonise their surfaces. Samples collected from transects across the SLR between Kingston and Cornwall, ON were dominated by the flat-bladed Vallisneria spp., and the leafed Myriophyllum spicatum, Elodea canadensis, Chara spp., Potamgeton spp., and Ceratophyllum spp. Overall, MIB and GM levels in biofilms ranged widely between samples. Expressed per g dry weight of biofilm, median levels from macrophyte were 50 (range 1-5000) ng MIB g(-1) and 10 (<1 to 580) ng GM g(-1) compared with 50 (range 5-970) ng MIB g(-1) and 160 (1-1600) ng GM g(-1) from rocks. Based on non-parametric statistical analysis, levels of GM were higher on a g dry weight basis in biofilms from rocks than macrophytes (P = 0.02), but MIB levels were similar (P = 0.94). However, when normalised for differences in substrate surface area (i.e. ng cm(-2)), levels of both MIB and GM were higher in biofilms from rocks than from macrophytes (P < 0.01). There were no discernable differences in MIB and GM concentrations from biofilms of different macrophytes based on either g dry weight sample or surface area (P > 0.05). Overlying water (OLW) concentrations ranged between 2-45 ng L(-1) for MIB and 5-30 ng L(-1) for GM and were not correlated with levels in adjacent biofilms. However, OLW concentrations peaked in shallow, low energy embayments consistent with enhanced production and release of MIB and GM in nearshore areas. The results support our previous work showing the importance of biofilms on various surfaces (rocks, macrophytes and zebra mussels) for MIB and GM production in the SLR, but suggest that inert surfaces like rocks are more productive sites per unit surface area than macrophytes. PMID:17489389

Ridal, J J; Watson, S B; Hickey, M B C

2007-01-01

201

Glacially-megalineated limestone terrain of Anticosti Island, Gulf of St. Lawrence, Canada; onset zone of the Laurentian Channel Ice Stream  

NASA Astrophysics Data System (ADS)

Anticosti is a large elongate island (240 km long, 60 km wide) in eastern Canada within the northern part of a deep water trough (Gulf of St. Lawrence) that terminates at the Atlantic continental shelf edge. The island's Pleistocene glaciological significance is that its long axis lay transverse to ice from the Quebec and Labrador sectors of the Laurentide Ice Sheet moving south from the relatively high-standing Canadian Shield. Recent glaciological reconstructions place a fast-flowing ice stream along the axis of the Gulf of St. Lawrence but supporting geologic evidence in terms of recognizing its hard-bedded onset zone and downstream streamlined soft bed is limited. Anticosti Island consists of gently southward-dipping limestone plains composed of Ordovician and Silurian limestones (Vaureal, Becscie and Jupiter formations) with north-facing escarpments transverse to regional ice flow. Glacial deposits are largely absent and limestone plains in the higher central plateau of the island retain a relict apparently ‘preglacial’ drainage system consisting of deeply-incised dendritic bedrock valleys. In contrast, the bedrock geomorphology of the lower lying western and eastern limestone plains of the island is strikingly different having been extensively modified by glacial erosion. Escarpments are glacially megalineated with a distinct ‘zig-zag’ planform reflecting northward-projecting bullet-shaped ‘noses’ (identified as rock drumlins) up to 2 km wide at their base and 4 km in length with rare megagrooved upper surfaces. Drumlins are separated by southward-closing, funnel-shaped ‘through valleys’ where former dendritic valleys have been extensively altered by the streaming of basal ice through gaps in the escarpments. Glacially-megalineated bedrock terrain such as on the western and eastern flanks of Anticosti Island is elsewhere associated with the hard-bedded onset zones of fast flowing ice streams and provides important ground truth for the postulated Laurentian Channel Ice Stream (LCIS) within the Gulf of St. Lawrence sector of the Laurentide Ice Sheet.

Eyles, Nick; Putkinen, Niko

2014-03-01

202

Evaluation of HVDC cables for the St. Lawrence River crossing of Hydro-Quebec's 500-kV DC line. Part 3; Thermal behavior  

SciTech Connect

This paper presents the thermal analyses conducted during the different stages of Hydro-Quebec's St. Lawrence river crossing project. It reveals the important impact of the thermal studies on the choice of HVDC cable and the design of the installations. It also describes the numerous problems faced during the cable prototype and demonstration tests and the solutions obtained by numerical analysis using the finite-element method. These problems were related in part to the temperature controls of the cable and its accessories, and in particular to the control of the temperature gradient across the dielectric material at various locations along the test loop.

Chaaban, M.; Leduc, J.; Couderc, D.; Trinh, N.G.; Belec, M. (Inst. de Recherche d'Hydro-Quebec, Varennes, Quebec J3X 1S1 (CA))

1992-04-01

203

Present-day stress analysis of the St. Lawrence Lowlands sedimentary basin (Canada) and implications for caprock integrity during CO2 injection operations  

NASA Astrophysics Data System (ADS)

A geomechanical analysis of the St. Lawrence Lowlands sedimentary basin is important to reliably estimate the maximum sustainable fluid pressures for CO2 injection that will not reactivate pre-existing faults in the caprock thereby inducing a breeched CO2 reservoir. This requires the determination of prevailing stresses (orientations and magnitudes), fault and fractures geometries and rock strengths. The average maximum horizontal stress orientation (SHmax) is estimated N59°E ± 20° in the St. Lawrence Lowlands. The stress orientations were obtained from stress-induced wellbore breakouts inferred from four-arm dipmeter caliper data in 17 wells. These wellbore failure features are confined to Paleozoic lithological units of the St. Lawrence Platform succession and frontal thrusts of the Quebec Appalachians at depths from 250 m to 4 km. Our results are consistent with the regional NE-SW SHmax stress orientation trend that is generally observed in eastern Canada and the U.S. The stresses/pressure gradients estimated for the St. Lawrence Lowlands (depths < 4 km) are: Shmin 20.5 ± 3 kPa/m, Sv 25.6 kPa/m, SHmax 40 ± 7.5 kPa/m, pore pressure Pp 9.8 kPa/m indicating a strike-slip stress regime Shmin < Sv < SHmax. The high-angle NE-SW regional faults and fractures in the Paleozoic sedimentary succession and the Grenvillian basement are oblique to the SHmax stress orientations (10° to 36°) and could be reactivated (slip tendency 0.34 to 0.58) under the present-day stress field if fluid pressures exceeded the critical threshold. Further refinement of regional geomechanical model is required to estimate the maximum sustainable injection pressure necessary for shear reactivation along the regional faults. The regional pore pressure-stress coupling ratio under assumed parameters is about 0.5-0.65 and may contribute to reduce the risk of shear reactivation of faults and fractures. The maximum sustainable Pp that would not cause opening of vertical tensile fractures during CO2 operations is about 18.5-20 MPa for the depth of 1 km.

Konstantinovskaya, E.; Malo, M.; Castillo, D. A.

2012-01-01

204

Predation on ruffe by native fishes of the St. Louis River Estuary, Lake Superior, 1989-1991  

USGS Publications Warehouse

The ruffe Gymnocephalus cernuus, an exotic Eurasian percid, recently became established in the St. Louis River estuary, Lake Superior, after accidental introduction. Management action (catch regulations and stocking) were enacted in 1989 to increase the density of top-level predators in the estuary, and thus to increase predation on ruffe. We conducted a field and laboratory study to determine if, and to what extent, native piscivores consume ruffe. Stomachs of 3,669 predators were examined in 1989-1991. Ruffe occurred in 6.7% of burbot Lota lota, 5.8% of bullheads Ictalurus spp., 4.7% of smallmouth bass Micropterus dolomieu, 2.6% of northern pike Esox lucius, 2.6% of black crappies Pomoxis nigromaculatus, and 1.3% of yellow perch Perca flavescens (4.5% after 1989) captured during the 3-year study. No ruffe were found in 967 stomachs of walleyes Stizostedion vitreum examined. Ruffe were 22.7% of the diet (by weight) of bullheads (during the only year bullheads were captured) and 0.1-17.9% of the diet of northern pike. Ruffe were 0.9-24.5% of the diet of smallmouth bass that contained fish, 1.5-6.9% of yellow perch that contained fish, and 0.0-10.9% of black crappies that contained fish. Most ruffe eaten were age-0 or small age-1 fish. In the laboratory, walleyes that were first fed soft-rayed prey or that were also offered soft-rayed prey consumed very few ruffe, whereas walleyes that were first fed spiny-rayed yellow perch or were also offered yellow perch consumed about equal numbers of ruffe and yellow perch. Northern pike and burbot consumed about equal numbers of ruffe and yellow perch in the laboratory. It is unlikely that predation will effectively control the initial expansion of ruffe in other areas of the Great Lakes because native predators initially consume few ruffe, especially if more preferred soft-rayed prey are available.

Ogle, Derek H.; Selgeby, James H.; Savino, Jacqueline F.; Newman, Raymond M.; Henry, Mary G.

1996-01-01

205

Application of Acoustic and Optic Methods for Estimating Suspended-Solids Concentrations in the St. Lucie River Estuary, Florida  

USGS Publications Warehouse

Acoustic and optic methods were applied to estimate suspended-solids concentrations in the St. Lucie River Estuary, southeastern Florida. Acoustic Doppler velocity meters were installed at the North Fork, Speedy Point, and Steele Point sites within the estuary. These sites provide varying flow, salinity, water-quality, and channel cross-sectional characteristics. The monitoring site at Steele Point was not used in the analyses because repeated instrument relocations (due to bridge construction) prevented a sufficient number of samples from being collected at the various locations. Acoustic and optic instruments were installed to collect water velocity, acoustic backscatter strength (ABS), and turbidity data that were used to assess the feasibility of estimating suspended-solids concentrations in the estuary. Other data collected at the monitoring sites include tidal stage, salinity, temperature, and periodic discharge measurements. Regression analyses were used to determine the relations of suspended-solids concentration to ABS and suspended-solids concentration to turbidity at the North Fork and Speedy Point sites. For samples used in regression analyses, measured suspended-solids concentrations at the North Fork and Speedy Point sites ranged from 3 to 37 milligrams per liter, and organic content ranged from 50 to 83 percent. Corresponding salinity for these samples ranged from 0.12 to 22.7 parts per thousand, and corresponding temperature ranged from 19.4 to 31.8 ?C. Relations determined using this technique are site specific and only describe suspended-solids concentrations at locations where data were collected. The suspended-solids concentration to ABS relation resulted in correlation coefficients of 0.78 and 0.63 at the North Fork and Speedy Point sites, respectively. The suspended-solids concentration to turbidity relation resulted in correlation coefficients of 0.73 and 0.89 at the North Fork and Speedy Point sites, respectively. The adequacy of the empirical equations seems to be limited by the number and distribution of suspended-solids samples collected throughout the expected concentration range at the North Fork and Speedy Point sites. Additionally, the ABS relations for both sites seem to overestimate at the low end and underestimate at the high end of the concentration range. Based on the sensitivity analysis, temperature had a greater effect than salinity on estimated suspended-solids concentrations. Temperature also appeared to affect ABS data, perhaps by changing the absorptive and reflective characteristics of the suspended material. Salinity and temperature had no observed effects on the turbidity relation at the North Fork and Speedy Point sites. Estimates of suspended-solids concentrations using ABS data were less 'erratic' than estimates using turbidity data. Combining ABS and turbidity data into one equation did not improve the accuracy of results, and therefore, was not considered.

Patino, Eduardo; Byrne, Michael J.

2004-01-01

206

Chlorinated hydrocarbons and mercury in sediments, red-winged blackbirds (Agelaius phoeniceus) and tree swallows (Tachycineta bicolor) from wetlands in the Great Lakes-St. Lawrence River basin  

SciTech Connect

In 1991, the authors collected red-winged blackbird (Agelauis phoeniceus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings, and sediment samples from 2 wetland sites in the Great lakes and St. Lawrence River basin. They analyzed for chlorinated hydrocarbons and total mercury and found that biota contained contaminant concentrations which were one to two orders of magnitude above those in sediments. Maximum concentrations of contaminants were found in Akwesasne, St. Lawrence river (PCBs = 18,558.8 ng/g in red-winged blackbird eggs, oxychlordane = 58.8/g and mirex = 40.1 ng/g in tree swallow eggs); Mud Creek, Lake Erie and Cootes Paradise. Despite the migratory habits of red-winged blackbirds and tree swallows, agreement among biota and sediment in geographic variation of contaminant concentrations supports the use of these animals as biomonitors of persistent chemicals. Although chlorinated hydrocarbon concentrations in red-winged blackbird eggs were significantly correlated with sediment contamination, the local nature of the tree swallow chick diet suggests that nestlings would be the best indicator of local contaminant trends.

Bishop, C.A. [Environment Canada, Burlington, Ontario (Canada); Koster, M.D. [Springborn Labs. (Europe) AG, Seestrasse (Switzerland); Chek, A.A. [Univ. of Guelph, Ontario (Canada). Dept. of Zoology; Hussell, D.J.T. [Ontario Ministry of Natural Resources, Maple, Ontario (Canada); Jock, K. [St. Regis Mohawk Health Service, Hogansburg, NY (United States)

1995-03-01

207

Modeling wetland plant community response to assess water-level regulation scenarios in the Lake Ontario-St. Lawrence River basin  

USGS Publications Warehouse

The International Joint Commission has recently completed a five-year study (2000-2005) to review the operation of structures controlling the flows and levels of the Lake Ontario - St. Lawrence River system. In addition to addressing the multitude of stakeholder interests, the regulation plan review also considers environmental sustainability and integrity of wetlands and various ecosystem components. The present paper outlines the general approach, scientific methodology and applied management considerations of studies quantifying the relationships between hydrology and wetland plant assemblages (% occurrence, surface area) in Lake Ontario and the Upper and Lower St. Lawrence River. Although similar study designs were used across the study region, different methodologies were required that were specifically adapted to suit the important regional differences between the lake and river systems, range in water-level variations, and confounding factors (geomorphic types, exposure, sediment characteristics, downstream gradient of water quality, origin of water masses in the Lower River). Performance indicators (metrics), such as total area of wetland in meadow marsh vegetation type, that link wetland response to water levels will be used to assess the effects of different regulation plans under current and future (climate change) water-supply scenarios.

Hudon, Christiane; Wilcox, Douglas; Ingram, Joel

2006-01-01

208

Toxicity of waters from the St. Lawrence River at Massena Area-of-Concern to the plankton species Selenastrum capricornutum and Ceriodaphnia dubia  

USGS Publications Warehouse

In 1972, the US and Canada committed to restore the chemical, physical, and biological integrity of the Great Lakes Ecosystem under the first Great Lakes Water Quality Agreement. During subsequent amendments, part of the St. Lawrence River at Massena NY, and segments of three tributaries, were designated as one Area of Concern (AOC) due to various beneficial use impairments (BUIs). Plankton beneficial use was designated impaired within this AOC because phytoplankton and zooplankton population data were unavailable or needed “further assessment”. Contaminated sediments from industrial waste disposal have been largely remediated, thus, the plankton BUI may currently be obsolete. The St. Lawrence River at Massena AOC remedial action plan established two criteria which may be used to assess the plankton BUI; the second states that, “in the absence of community structure data, plankton bioassays confirm no toxicity impact in ambient waters”. This study was implemented during 2011 to determine whether this criterion was achieved. Acute toxicity and chronic toxicity of local waters were quantified seasonally using standardized bioassays with green alga Selenastrum capricornutum and water flea Ceriodaphnia dubia to test the hypothesis that waters from sites within the AOC were no more toxic than were waters from adjacent reference sites. The results of univariate and multivariate analyses confirm that ambient waters from most AOC sites (and seasons) were not toxic to both species. Assuming both test species represent natural plankton assemblages, the quality of surface waters throughout most of this AOC should not seriously impair the health of resident plankton communities.

Baldigo, Barry P.; Duffy, Brian T.; Nally, Christopher J.; David, Anthony M.

2012-01-01

209

Temporal and spatial distribution and production of dissolved gaseous mercury in the Bay St. François wetland, in the St. Lawrence River, Quebec, Canada  

Microsoft Academic Search

Wetlands are valued for their high biodiversity and for their ecosystem services. However, we still do have a poor understanding of their role in the redox transformation of contaminants such as mercury, particularly in fluvial settings. Seasonal and spatial variations in dissolved gaseous mercury (DGM) distribution and production were studied in the Bay St. François, a wetland in the St.

Edenise Garcia; Jerôme Laroulandie; Xavier R. Saint-Simon; Marc Amyot

2006-01-01

210

Relative importance of pelagic and sediment respiration in causing hypoxia in a deep estuary  

NASA Astrophysics Data System (ADS)

Oxygen depletion in the 100-m thick bottom layer of the deep Lower St. Lawrence Estuary is currently thought to be principally caused by benthic oxygen demand overcoming turbulent oxygenation from overlying layers, with pelagic respiration playing a secondary role. This conception is revisited with idealized numerical simulations, historical oxygen observations and new turbulence measurements. Results indicate that a dominant sediment oxygen demand, over pelagic, is incompatible with the shape of observed oxygen profiles. It is further argued that to sustain oxygen depletion, the turbulent diffusivity in the bottom waters should be ?10-4 m2 s-1, consistent with direct measurements but contrary to previous model results. A new model that includes an Arrhenius-type function for pelagic respiration and a parameterization for turbulence diffusivity is developed. The model demonstrates the importance of the bottom boundary layer in reproducing the shape of oxygen profiles and reproduces to within 14% the observed change in oxygen concentration in the Lower St. Lawrence Estuary. The analysis indicates that turbulent oxygenation represents about 8% of the sum of sediment and pelagic oxygen demand, consistent with the low turbulent oxygenation required to maintain oxygen depletion. However, contrary to previous hypotheses, it is concluded that pelagic oxygen demand needs to be five time larger than sediment oxygen demand to explain hypoxia in the 100-m thick bottom layer of the Lower St. Lawrence Estuary.

Bourgault, D.; Cyr, F.; Galbraith, P. S.; Pelletier, E.

2012-08-01

211

Chemical and microbial contamination baseline in the Saguenay-St. Lawrence Marine Park (Eastern Canada): concentrations and fluxes from land-based sources.  

PubMed

Stretching halfway between the Canadian Great Lakes and the Atlantic Ocean, the Saguenay-St. Lawrence Marine Park is subject to environmental issues being exposed to untreated or uncontrolled point and non-point sources of anthropogenic contamination. This article provides a first estimation of chemical and microbial contamination entering the marine park from the discharges of local municipal effluents and the inputs of tributaries in the summer period. Suspended particulate matter (SPM), nutrients, particulate carbon (PC) and nitrogen, trace metals, and fecal coliform bacteria were determined in surface brackish waters at upstream boundaries, in freshwater of 11 tributaries, and in nine sewage effluents from small communities settled along the marine park. Most tributaries have SPM < 10 mg L(-1) and contributed to a total of ~47 tons day(-1), thus representing a small proportion of daily SPM transported by Saguenay River (200 tons day(-1)) and St. Lawrence River (6.3 × 10(3) tons day(-1)). As expected, untreated sewage effluents showed high fecal contamination (0.2-6.0 × 10(6) CFU 100 mL(-1)), high NO x levels (4-33 ?mol L(-1)) and high concentrations of particulate organic carbon (7-62 mg L(-1)). However, all tributaries had low coliforms (<230 CFU 100 mL(-1)), low PC (0.3-1.1 mg L(-1)), and low nutrients (NO(x) < 3.3 ?mol L(-1)), with the exception of the Moulin-à-Baude River, a small tributary (2.3 × 10(5) m(3) day(-1)) clearly contaminated by human activities. Detailed analysis of 14 metals and metalloids in SPM did not show any clear contamination trend between sewage effluents and tributaries, except for Grandes-Bergeronnes River, where most trace metals appeared to be greater than for other rivers. Regarding global inputs, results showed that despite their relatively high pollutants load, inputs from local sewages and small tributaries remained minor contributors compared with upstream inputs, i.e., Saguenay River and St. Lawrence River. However, we illustrate that some local hydrodynamic factors in bays and inlets must be taken into account when evaluating risks associated with sewage discharges. PMID:23695715

Lemaire, Nicolas; Pelletier, Émilien

2013-10-01

212

Evaluation of HVDC cables for the St. Lawrence crossing of Hydro-Quebec 500 kV DC Line. Part 1; Dielectric and accelerated aging tests on prototypes  

SciTech Connect

This paper describes the dielectric and accelerated aging tests on prototype {plus minus}500 kV dc oil-filled self-contained cables. The extensive test program was required to evaluate the High-Voltage cables for the St. Lawrence river crossing of the {plus minus}500 kV Quebec-New England HVDC power transmission system. The paper relates the main elements of the test program. It describes the required insulation levels, the characteristics of the cables supplied by three different manufacturers, as well as the cables' installation for the type tests and accelerated aging tests. Details of the test program and procedures followed to carry out the tests are given. Findings of the tests are also reported.

Coudere, D.; Trinh, N.G.; Belec, M.; Chaaban, M.; Leduc, J.; Beausejour, Y. (Inst. de Recherche d'Hydro-Quebec, Varennes, Quebec J3X 1S1 (CA))

1992-04-01

213

Endocrine and metabolic dysfunction in yellow perch, Perca flavescens, exposed to organic contaminants and heavy metals in the St. Lawrence River  

SciTech Connect

The endocrine and biochemical responses to the acute stress of capture and handling were investigated in sexually mature and in immature male and female yellow perch, Perca flavescens, from a site contaminated by organic contaminants (PAHs and PCBs) and heavy metals (Hg, Cd, As, and Zn) and from a reference site in the St. Lawrence River. Following a standardized capture and handling stress, fish from the contaminated site did not exhibit the expected physiological stress response observed in fish from the reference site. Blood cortisol and thyroxine levels were lower, and liver glycogen stores were greater in mature males and females, as well as in the immature fish from the contaminated site, compared to the reference site. Fish from the contaminated site also had smaller gonads and lower condition factor. The impaired ability to elevate blood cortisol in response to an acute stress may be used as a biomarker of toxic stress in health assessment of feral fish from polluted environments.

Hontela, A.; Duclos, D.; Fortin, R. [Univ. du Quebec, Montreal, Quebec (Canada). Dept. Sciences Biologiques; Dumont, P. [Ministere du Loisir, Montreal, Quebec (Canada)

1995-04-01

214

Les échanges surface-atmosphère du mercure gazeux dans l'écosystème lac Ontario\\/fleuve Saint-Laurent Mercury Surface-Atmosphère Gas Exchange in Lake Ontario\\/St. Lawrence River Ecosystem  

Microsoft Academic Search

SUMMARY This paper présents and discusses mercury surface-atmosphère gas exchange in Lake Ontario\\/St. Lawrence River ecosystem. Atmospheric sources are recognised to be significant in the cycling of global mercury. Being volatile in its elemental and dimethylated forms, mercury is distributed Worldwide. The dominant form of mercury in the atmosphère is gaseous elemental mercury (Hg(°) (- 98%). Cycling of atmospheric mercury

L. POISSANT

215

Turbulent nitrate fluxes near a sill in a large estuary  

NASA Astrophysics Data System (ADS)

Historical nitrate concentration profiles and new turbulent microstructure observations were combined to calculate turbulent nitrate fluxes in the Lower St. Lawrence Estuary (LSLE), Canada. Two stations were compared: the head of the Laurentian Channel (st. 25), where intense mixing occurs on the shallow sill that marks the upstream limit of the LSLE, and another station located about 100 km downstream (st. 23). Nitrate fluxes at the base of the surface layer for both stations were respectively (with the 95% confidence interval): F25 = 64(23,130)mmolm-2 d-1 and F23 = 0.11(0.04,0.23)mmolm-2 d-1. Observations suggest that the interplay between large isopleths heaving near the sill and strong turbulence is the key mechanism to sustain such high turbulent nitrate fluxes at station 25 (about 600 times those at station 23). Calculations also suggest that these localised large fluxes can sustain almost entirely the post-bloom new production over the whole LSLE.

Cyr, Frédéric; Bourgault, Daniel; Galbraith, Peter S.; Gosselin, Michel

2014-05-01

216

St  

Cancer.gov

St. Joseph Hospital Cancer Institute Physician Conditions of Participation A. PREAMBLE The vision of St. Joseph Hospital Cancer Institute is to attain the highest level of clinical excellence while providing an exceptional patient

217

Speciation and transformation of phosphorus and its mixing behavior in the Bay of St. Louis estuary in the northern Gulf of Mexico  

NASA Astrophysics Data System (ADS)

Water samples were collected for measurements of dissolved, colloidal, and particulate inorganic and organic phosphorus (P) from the Bay of St. Louis estuary in the northern Gulf of Mexico during August 2008 and October 2009. Laboratory mixing experiments were also carried out using end-member river water and seawater to examine key processes and mechanisms controlling the behavior of P during estuarine mixing. Dissolved organic P (DOP) was the dominant species in the total dissolved P (TDP) pool in both lower (S < 10) and higher salinity (S > 25) regions, while dissolved inorganic P (DIP) predominated in mid-salinity regions (S of 10˜20) comprising up to 75% of the TDP. Both DIP and DOP behaved non-conservatively during estuarine mixing showing dramatic changes and transformation between different P species. The total particulate phosphorus (TPP) accounted for up to 85% of total phosphorus (TP = TDP + TPP) in the low-salinity areas but fell to about 38% in higher salinity regions. The quasi-negative correlation between TDP and TPP and the similarity in mixing behavior between field observations and laboratory experiments supported our hypothesis that physicochemical processes, such as dynamic repartitioning between water and particles or adsorption/desorption, are the predominant mechanisms controlling the biogeochemical cycling of P species in the Bay of St. Louis. River export fluxes of DIP could be significantly underestimated without the quantification of particulate P species, especially in more pristine river basins. The value of the distribution coefficient (in terms of logKd) ranged from 4.4 to 5.6 and decreased with increasing suspended particulate matter concentration and salinity, indicating that P is highly particle reactive and the presence of colloidal P may play an important role in the cycling of P in estuarine environments. Colloidal inorganic P (CIP) and colloidal organic P (COP), as quantified by an ultrafiltration permeation model, comprised 0-62% of the DIP and 34-93% of the DOP with the highest values in the river mouth area, suggesting a river source for colloidal P. The % CIP dropped to below the detection limit as salinity increased, whereas % COP first decreased but increased again with increasing salinity, reflecting different sources for CIP and COP in the lower estuary. The DOC/DOP ratio decreased rapidly with increasing salinity indicating a diagenetically older dissolved organic matter pool from the river and a dynamic change in sources and chemical speciation of P in the estuary.

Lin, Peng; Chen, Min; Guo, Laodong

2012-06-01

218

Putting oxygen and temperature thresholds of marine animals in context of environmental change in coastal seas: a regional perspective for the Scotian Shelf and Gulf of St. Lawrence  

NASA Astrophysics Data System (ADS)

We surveyed the literature in order to compile reported oxygen, temperature, salinity and depth preferences and thresholds of important marine species found in the Gulf of St. Lawrence and the Scotian Shelf regions of the northwest North Atlantic. We determined species importance based on the existence of a commercial fishery, a threatened or at risk status, or by meeting the following criteria: bycatch, baitfish, invasive, vagrant, important for ecosystem energy transfer, and predators and prey of the above species. Using the dataset compiled for the 53 regional fishes and macroinvertebrates, we rank species (including for different lifestages) by their maximum thermal limit, as well as by the lowest oxygen concentration tolerated before negative impacts (e.g. physiological stress), 50% mortality or 100% mortality are experienced. Additionally, we compare these thresholds to observed marine deoxygenation trends at multiple sites, and observed surface warming trends. This results in an assessment of which regional species are most vulnerable to future warming and oxygen depletion, and a first-order estimate of the consequences of thermal and oxygen stress on a highly productive marine shelf. If regional multi-decadal oxygen and temperature trends continue through the 21st century, many species will lose favorable oxygen conditions, experience oxygen-stress, or disappear due to insufficient oxygen. Future warming can additionally displace vulnerable species, though we note that large natural variability in environmental conditions may amplify or dampen the effects of anthropogenic surface warming trends. This dataset may be combined with regional ocean model predictions to map future species distributions.

Brennan, Catherine E.; Blanchard, Hannah; Fennel, Katja

2014-05-01

219

Headwater locations of U.S. streams tributary to St. Lawrence River basin between western Ohio and eastern New York, excluding Lake Champlain basin  

USGS Publications Warehouse

The headwater locations of several thousand U.S. streams tributary to Lakes Ontario and Erie and the St. Lawrence and Niagara Rivers, from the Maumee River in Ohio to the western border of the Lake Champlain basin in New York, including parts of Pennsylvania, are listed by quadrangle. The location of the headwater of each is given with reference to cultural and topographic features. ' Headwater ' in this report is defined as the first site downstream from which the average streamflow is 5 cubic feet per second. The site locations were determined from drainage areas as indicated on topographic maps. The size of the drainage area required to produce an average flow of 5 cubic feet per second was determined from equations, developed separately for each State by regression techniques, that define the relation between streamflow and hydrologic factors of the region. Drainage area and precipitation were factors in the equations for all three States: forest cover was found to be significant in Ohio. (Woodard-USGS)

Eissler, Benjamin B.

1979-01-01

220

Intra- and inter-species differences in persistent organic contaminants in the blubber of blue whales and humpback whales from the Gulf of St. Lawrence, Canada.  

PubMed

Biopsy samples of blubber from adult male and female blue whales, and from female and young-of-the-year humpback whales were collected during the summers of 1992-1999 in the Gulf of St. Lawrence, Canada. In blue whales, concentrations of 25 PCB congeners, DDT and metabolites and several other organochlorine compounds were present at higher concentrations in the blubber of males relative to females; reflecting maternal transfer of these persistent contaminants from females into young. Sex-related differences in concentrations were not observed with less persistent contaminants, such as HCHs. In humpback whale samples, there were no significant differences in the concentrations of PCBs and organochlorine compounds in the blubber of females and calves. These data indicate that calves quickly bioaccumulate contaminants by transplacental and lactational routes to concentrations that are in equilibrium with females. In comparisons between contaminant concentrations and patterns in the blubber of female blue and humpback whales, there were no significant differences in concentrations, but the proportions of some PCB congeners, HCH isomers, and DDT and its metabolites were different in the two baleen whale species. These may reflect differences in the diet of the two species, since fish comprise a large part of the diet of humpback whales and blue whales feed exclusively on euphausiid crustaceans (i.e. krill). PMID:14749058

Metcalfe, Chris; Koenig, Brenda; Metcalfe, Tracy; Paterson, Gordon; Sears, Richard

2004-05-01

221

Health assessment for General Motors Central Foundry, St. Lawrence County, Massena, New York, Region 2. CERCLIS No. NYD091972554. Preliminary report  

SciTech Connect

The General Motors Central Foundry Division is an aluminum casting plant on 270 acres located on the south bank of the St. Lawrence River in Massena, New York. The plant has been in operation since 1959. Polychlorinated biphenyls (PCBs) were used in the hydraulic fluids for die-casting machines from 1968-1973. Sludges containing PCBs were landfilled in on-site disposal pits, in an industrial landfill, and in several lagoons on-site. Soils, ground water and river sediments are known to be contaminated. PCB contaminated sludges and soils are estimated to be in excess of 370,000 cubic yards at concentrations greater than 25 mg/kg (dry weight). Ground water and surface water standards for PCBs were exceeded. Potential environmental pathways include contaminated ground water, surface water, soil, and air. The consumption of contaminated fish and wildlife of the food chain is particularly significant at this site because of the close proximity of the Mohawk Indian Reservation, whose residents include large amounts of local fish and wildlife in their diets.

Not Available

1989-06-30

222

Meltwater discharge and the triggering of Younger Dryas : new data on the chronology of Champlain Sea transgression in the St-Lawrence River Valley  

NASA Astrophysics Data System (ADS)

Accurate chronology of ice retreat is crucial to understand the Ocean-Atmosphere couple at the end of the Pleistocene. The St-Lawrence River Valley is key in this regard, and two sedimentary sequences from Mount Saint-Hilaire, in the middle of the valley, contain a record that sheds new lignt on ice retreat and the penecontemporaneous proglacial marine invasion. Basal AMS-dates on terrestrial plant macrofossils coupled with an extrapolation from the pollen content of underlying postglacial lake sediments at Hemlock Carr (243 m), show that local ice retreat occurred around 11 350 14C yr BP. Cross-dating of such macrofossils (10 510 ± 60 14C yr BP) with shells from marine sediments (~12 200 14C yr BP) catched in the neighbouring Lake Hertel's basin (169 m) show a ca. 1700 14C years difference mainly ascribed to the effect of old, glacially-derived carbon in the upper shallow waters of the Champlain Sea. The pollen-based chronological extrapolation at Lake Hertel indicates that the marine invasion occurred around 11 100 ± 100 14C yr BP. This result supports the chronology based on deep-water invertebrate marine fauna (Rodrigues, 1988). The 14C assessment of the New-England varve chronology (Ridge et al., 1999) is thus confirmed. Deglaciation of the entire Saint-Lawrence River Valley took place within 1000 14C years. The chronology of ice retreat in southern Québec is shortened and made younger. This prompts major revision of all the associated paleohydrological events. Routing of the glacial meltwaters to the North Atlantic was impossible before 11 100 14C yr BP. The abrupt transition from Glacial Lake Candona (ca. 220 m) to the proglacial phase of the Champlain Sea (ca. 190 m) at 11 100 14C yr BP implies an input of glacial meltwater to the ocean estimated at 1500 km3. This may well have affected the thermohaline circulation in the North Atlantic and triggered the Younger Dryas oscillation.

Richard, P.; Occhietti, S.

2004-05-01

223

Gill and head kidney antioxidant processes and innate immune system responses of yellow perch (Perca flavescens) exposed to different contaminants in the St. Lawrence River, Canada.  

PubMed

Biomarkers of oxidative stress metabolism and the innate immune response were examined in gill and head kidney tissue of wild-caught yellow perch (Perca flavescens) collected from four sites ranging in type and degree of metal pollution in the St. Lawrence River, Quebec, Canada. Sites were ranked as follows: Ile Dorval

Dautremepuits, Claire; Marcogliese, David J; Gendron, Andrée D; Fournier, Michel

2009-01-15

224

Is the bone tissue of ring-billed gulls breeding in a pollution hotspot in the St. Lawrence River, Canada, impacted by halogenated flame retardant exposure?  

PubMed

Bone metabolism is a tightly regulated process that controls bone remodeling and repair in addition to maintaining circulating calcium and phosphate levels. It has been shown that certain organohalogen contaminants may adversely impact bone tissue metabolism and structure in wildlife species. However, exceedingly few studies have addressed the bone-related effects of organohalogen exposure in birds. The objective of the present study was to investigate the associations between markers of bone metabolism and structural integrity, and concentrations of established and current-use halogenated flame retardants (FRs) in ring-billed gulls (Larus delawarensis) nesting in a known FR hotspot area in the St. Lawrence River (Montreal, Canada). Bone metabolism was assessed using plasma calcium and inorganic phosphate levels, and alkaline phophatase activity, while bone (tarsus; trabecular and cortical sections) structure quality was examined using the percentage of bone tissue comprised in the total bone volume (Bv/Tv) and bone mineral density (BMD). Bv/Tv and BMD of the tarsus tended (not significant) to be positively associated with circulating calcium levels in male ring-billed gulls. Moreover, concentrations of FRs in male bird liver (brominated diphenyl ether (BDE)-154, -183, -201, and -209) and plasma (BDE-209) were negatively correlated with trabecular and cortical BMD of the tarsus. These correlative associations may suggest light demineralization of bone tissue associated with FR exposure in male ring-billed gulls. Present findings provide some evidence that bone (tarsus) metabolism and mineral composition may be impacted in high FR-exposed (mainly to PBDEs) ring-billed gulls breeding in the highly urbanized Montreal region. PMID:24016627

Plourde, Stéphanie Pellerin; Moreau, Robert; Letcher, Robert J; Verreault, Jonathan

2013-11-01

225

Spatial and temporal trends of mercury concentrations in young-of-the-year spottail shiners (Notropis hudsonius) in the St. Lawrence River at Cornwall, ON.  

PubMed

The St. Lawrence River at Cornwall, Ontario is an "Area of Concern" because of mercury (Hg) biomagnification from bottom sediments. To assess the spatial and temporal distribution of Hg in the food web, young-of-the-year (YOY) spottail shiners (Notropis hudsonius) were collected in August 2005 from five sites along the Cornwall waterfront within a Hg-contaminated zone and two reference zones. The results were compared to analyses made between 1979 and 2000 by the Ontario Ministry of the Environment. Total Hg concentrations in spottail shiners from the contaminated zone were significantly higher than in reference zones, confirming previous observations. Within the contaminated zone, there were significant differences in Hg concentrations among three sites spaced about 500 m apart, consistent with a high degree of site fidelity of YOY fish and suggesting a possible internal source of Hg. Hg concentrations in spottail shiners are decreasing regionally, although year-to-year variability was high, particularly in the contaminated zone. Stable isotope analyses of spottail shiners did not reveal any differences in nitrogen isotope composition among zones that would indicate differences in food-web structure and Hg biomagnification. However, carbon sources at an upstream reference zone were not the same as within the Area of Concern. Differences in carbon isotope composition at two sites within the contaminated zone corresponded to differences in Hg concentrations, consistent with a unique internal source of Hg. The variation in Hg contamination of YOY spottail shiners over fine spatial and temporal scales provide important insights about the potential release of Hg from contaminated sediments and the role of climate in regional trends. Sessile YOY fish provide a precise indicator for demonstrating these differences and for assessing their cause. PMID:17909881

Choy, Emily S; Hodson, Peter V; Campbell, Linda M; Fowlie, Adrienne R; Ridal, Jeff

2008-04-01

226

Annual dissolved nitrite plus nitrate and total phosphorous loads for the Susquehanna, St. Lawrence, Mississippi-Atchafalaya, and Columbia River basins, 1968-2004  

USGS Publications Warehouse

Annual stream-water loads were calculated near the outlet of four of the larger river basins (Susquehanna, St. Lawrence, Mississippi-Atchafalaya, and Columbia) in the United States for dissolved nitrite plus nitrate (NO2 + NO3) and total phosphorus using LOADEST load estimation software. Loads were estimated for the period 1968-2004; although loads estimated for individual river basins and chemical constituent combinations typically were for shorter time periods due to limitations in data availability. Stream discharge and water-quality data for load estimates were obtained from the U.S. Geological Survey (USGS) with additional stream discharge data for the Mississippi-Atchafalaya River Basin from the U.S. Army Corps of Engineers. The loads were estimated to support national assessments of changes in stream nutrient loads that are periodically conducted by Federal agencies (for example, U.S. Environmental Protection Agency) and other water- and land-resource organizations. Data, methods, and results of load estimates are summarized herein; including World Wide Web links to electronic ASCII text files containing the raw data. The load estimates are compared to dissolved NO2 + NO3 loads for three of the large river basins from 1971 to 1998 that the USGS provided during 2001 to The H. John Heinz III Center for Science, Economics and the Environment (The Heinz Center) for a report The Heinz Center published during 2002. Differences in the load estimates are the result of using the most up-to-date monitoring data since the 2001 analysis, differences in how concentrations less than the reporting limit were handled by the load estimation models, and some errors and exclusions in the 2001 analysis datasets (which resulted in some inaccurate load estimates).

Aulenbach, Brent T.

2006-01-01

227

A multi-level biological approach to evaluate impacts of a major municipal effluent in wild St. Lawrence River yellow perch (Perca flavescens).  

PubMed

The development of integrated ecotoxicological approaches is of great interest in the investigation of global concerns such as impacts of municipal wastewater effluents on aquatic ecosystems. The objective of this study was to investigate the effects of a major wastewater municipal effluent on fish using a multi-level biological approach, from gene transcription and enzyme activities to histological changes. Yellow perch (Perca flavescens) were selected based on their wide distribution, their commercial and recreational importance, and the availability of a customized microarray. Yellow perch were sampled upstream of a major municipal wastewater treatment plant (WWTP) and 4km and 10km downstream from its point of discharge in the St. Lawrence River (Quebec, Canada). Concentrations of perfluoroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and metals/trace elements in whole body homogenates were comparable to those from other industrialized regions of the world. Genomic results indicated that the transcription level of 177 genes was significantly different (p<0.024) between exposed and non-exposed fish. Among these genes, 38 were found to be differentially transcribed at both downstream sites. Impacted genes were associated with biological processes and molecular functions such as immunity, detoxification, lipid metabolism/energy homeostasis (e.g., peroxisome proliferation), and retinol metabolism suggesting impact of WWTP on these systems. Moreover, antioxidant enzyme activities were more elevated in perch collected at the 4km site. Biomarkers of lipid metabolism, biosynthetic activity, and aerobic capacities were significantly lower (p<0.05) in fish residing near the outfall of the effluent. Histological examination of the liver indicated no differences between sites. Correlations between PFAS, PBDE, and metal/trace element tissue concentrations and markers of peroxisomal proliferation, oxidative stress, and retinoid metabolism were found at the gene and cellular levels. Present results suggest that relating transcriptomic analyses to phenotypic responses is important to better understand impacts of environmental contamination on wild fish populations. PMID:25137380

Houde, Magali; Giraudo, Maeva; Douville, Mélanie; Bougas, Bérénice; Couture, Patrice; De Silva, Amila O; Spencer, Christine; Lair, Stéphane; Verreault, Jonathan; Bernatchez, Louis; Gagnon, Christian

2014-11-01

228

Contribution of active and passive acoustics to study oceanographic processes feeding whales in a critical habitat of the St. Lawrence Estuary  

NASA Astrophysics Data System (ADS)

The head of the main channel of the continent in eastern Canada is the site of particular oceanographic processes that are responsible for the creation of a persistent feeding ground regularly visited by baleen whales from the Atlantic for centuries. Multifrequency acoustics coupled with ADCP and hydrographic measurements has been used to map the krill and capelin aggregations in 3D and visualize their local concentration process under tidal forcing and upwelling at the channel head. The krill scattering layers, pumped into the area by the strong two-layer estuarine circulation, appear to be concentrated during flood by tidal currents forced against the slopes and upwelling, to which depth-keeping krill is reacting by swimming down. Capelin also tends to concentrate on slopes and neighboring shallows. This highly recurrent process generates rich patches that are contributing with the mean circulation to make this area the richest krill aggregation in Northwest Atlantic. This critical habitat is located in a major continental seaway. Passive acoustics techniques are explored to locate whale calls and map the use of this area in continuing months, especially by blue and fin whales, with the aim of understanding their movements to improve their protection.

Simard, Yvan; Roy, Nathalie; Simard, Yvan; Cotté, Cédric

2001-05-01

229

Environmental Health Perspectives VOLUME 110 | NUMBER 3 | March 2002 285 Cancer in Wildlife, a Case Study: Beluga from the St. Lawrence Estuary,  

E-print Network

are heavily contaminated by agricultural and industrial contaminants such as heavy metals, poly- cyclic), Québec, Canada, receives the effluent from one of the most industrialized regions of the world (Figure 1 government in 1980 (3). Yet no solid data indicate population recovery. To explain this apparent failure

Hahn, Mark E.

230

Exploring Estuaries  

NSDL National Science Digital Library

Exploring Estuaries introduces students of various ages to the ecology of estuaries, places where freshwater rivers and streams flow into the ocean, mixing with the seawater. It is part of a broader effort by the National Estuary Program to educate the general public about estuaries and to restore and protect these sensitive ecosystems. It offers interactive games and activities as well as virtual tours of Long Island Sound and the Barataria-Terrebonne Estuarine Complex near New Orleans. A glossary page defines technical terms used throughout the site. Resources also are provided for teachers and students interested in learning more about related organizations, publications, and websites.

231

Evaluation of HVDC cables for the St. Lawrence River crossing of Hydro-Quebec's 500 kV DC line. Part 2; Cable testing facility for dielectric and accelerated aging  

SciTech Connect

This paper describes the new cable testing facility at IREQ for long-term accelerated aging tests on HV cables. This test facility was required as part of an extensive program to evaluate the high-voltage cables for the river crossing of Hydro-Quebec's new transmission lines rated 800 kV AC and {plus minus}500 kV DC. The first application was for the evaluation of self-contained oil-filled (SCOF) cables for the St. Lawrence river crossing of the {plus minus}500 kV Quebec-New England HVDC power transmission system. The paper also describes the specific dielectric constraints resulting from the insertion of a short length of cable into a long line and, also, the circuits developed for the special tests, which reproduce the specific cable test conditions.

Trinh, N.G.; Couderc, D.; Faucher, P.; Chaaban, M.; Belec, M.; Leduc, J. (Inst. de Recherche d'Hydro-Quebec, Varennes, Quebec J3X 1S1 (CA))

1992-04-01

232

Water and sediment dynamics at Saint Lawrence River mouth  

Microsoft Academic Search

The main features of the hydrological regime and morphological structure of the estuarine-type mouth area of the Saint Lawrence\\u000a River are considered. Data on the structure of water masses, thermal and ice regimes in the Gulf of Saint Lawrence, which\\u000a has a significant effect on the estuary, are given. The major attention is paid to water mixing processes, water and

E. N. Dolgopolova; M. V. Isupova

2011-01-01

233

Common cyclicities in the seismicity and water level fluctuations at the charlevoix seismic zone on the St Lawrence River, Quebec, Canada  

NASA Astrophysics Data System (ADS)

Intraplate seismicity has no widely accepted explanation for its origin. The hydroseismicity hypothesis suggests that natural increases in hydraulic head, caused by transient increases in water table elevation, can be transmitted to hypocentral depths (10-25 km) in a fractured, prestressed, near-failure crust, and, along with long term hydrolytic weakening of rocks, contribute to the triggering of earthquakes. In this study, the temporal characteristics of seismicity and water level fluctuations at the Charlevoix seismic zone on the Saint Lawrence River in Quebec, Canada, are determined using Fourier spectral analysis and are investigated for possible temporal relationships, as predicted by hydroseismicity, using group delay analysis. Fourier spectral analysis of the temporal release of seismic energy indicates the presence of short term cyclicities of periods of 13-14 yr, along with longer term periods of approx. 55-70 yr. Spectral analysis of the water level data indicates cyclicities with periods of 1, 23, 14 and 8 years. Group delay analysis of the 14 yr periodicities in the water level and seismicity time series yields a time lag of 2.3-2.6 yr, with the water levels leading the seismicity time series. Crustal diffusivity values estimated from the group delay analysis range between 0.3 and 2.7 m 2/s, for a depth interval from 7 to 20 km, which is within the range of published values of diffusivities for the crust (0.1-100 m 2/sec). The present study suggests that common cyclicities are present in both the water levels and seismicity in the Charlevoix region. Such cyclicities are an essential element of the hydroseismicity hypothesis for the diffusion of surficial fluid pressure variations to hypocentral depths. Furthermore, the temporal relationship between the cyclicities observed allows for a possible causal relationship between repetitive mechanical effects of pore pressure transients and seismicity in the Charlevoix region.

Tsoflias, George P.; Bollinger, G. A.; Costain, John K.

1995-03-01

234

Estuary Live!!!  

NSDL National Science Digital Library

Intended for elementary, middle, and high school students, this electronic estuary excursion, Estuary Live!!!, will take place May 8-12, 2000. Free to participants (but please sign up in advance), the field trip will explore the Rachel Carson Site of the North Carolina National Estuarine Research Reserve, covering four islands and salt marshes off the North Carolina coast. The site features useful educational materials, including a photo-illustrated field guide (of the "ecology, habitats and specific plants and animals found in North Carolina's estuaries"); lesson plans (covering highschool biology, estuary habitats, species interactions, and adaptations and communities); and a series of related links. The interactive field trip will require a java-enabled browser, RealVideo (to see a moving image and hear sound), and/or Chatvideo, to see a moving image, ask questions of the naturalist leading the trip, and receive responses via a chat window. Note that ChatVideo requires Netscape 4.0 or better and will not work with AOL or Internet Explorer, and pages "look best" on a screen with resolution of 800x600. The Estuary Live!!! Website is provided by the North Carolina National Estuarine Research Reserve Program, and The Center for Science, Mathematics and Technology Education at East Carolina University.

235

Exploring Estuaries  

NSDL National Science Digital Library

This site offers several ways to explore the importance of estuaries. Virtual tours of the Barataria-Terrebone Estuarine Complex and the Long Island Sound offer photos and text of each area explain their importance to humans, wildlife, and larger ecosystems. Additional resources for kids and adults are linked. A glossary page offers a list of vocabulary associated with estuaries. The site also offers a games and activities section for kids that has coloring sheets for young children, and inquiry-based interactive games for older kids. The games include a "Who Am I" animal identification game, and a game called "Solve a Mystery" where players must follow and investigation into what's wrong with an estuary, and make a decision on the cause of the problem. There are several possible mysteries to solve, each with a different solution.

236

Maturity, size at age and predator-prey relationships of winter skate Leucoraja ocellata in the southern Gulf of St Lawrence: potentially an undescribed endemic facing extirpation.  

PubMed

The goals of this study were to document the size and age structure, size at maturity, ovarian fecundity and diet of the endangered population of winter skate Leucoraja ocellata that resides in the southern Gulf of St Lawrence (SGSL). The maximum size observed for SGSL L. ocellata was 68?cm total length (LT ) but >99% of animals caught were <60?cm LT . Fifty per cent of male and female L. ocellata were fully mature at 40 and 42?cm LT , respectively, age c. 5?years. The oldest individual caught was age 11?years, but 98% of the 561 individuals examined were ?age 8?years, indicating a short reproductive life span. Ovarian fecundity was low; no more than 29 ova >10 mm diameter were ever observed. At 40?cm LT , the diet changed from one dominated by shrimp Crangon septemspinosa and gammarid amphipods to one dominated by fishes (mainly sand lance Ammodytes spp. and rainbow smelt Osmerus mordax) and Atlantic rock crab Cancer irroratus. Sufficient differences were observed between SGSL L. ocellata and other populations in their size-at-maturity pattern and maximum size to propose the taxonomic re-evaluation of the population. PMID:23464554

Kelly, J T; Hanson, J M

2013-03-01

237

Classification of Estuaries  

NSDL National Science Digital Library

This text states that although all estuaries are similar in that they are semi-enclosed bodies of brackish water, they are categorized with regard to geological characteristics, and further distinguished on the basis of stratification and circulation patterns. According to their geological characteristics, estuaries are classified as: drowned river valleys or coastal-plain estuaries, bar-built estuaries or lagoons, fjord-type estuaries, and tectonically caused estuaries. Each type is explained in detail and examples are given for each.

238

Classification of Estuaries  

NSDL National Science Digital Library

This text states that although all estuaries are similar in that they are semi-enclosed bodies of brackish water, they are categorized with regard to geological characteristics, and further distinguished on the basis of stratification and circulation patterns. According to their geological characteristics, estuaries are classified as: drowned river valleys or coastal-plain estuaries, bar-built estuaries or lagoons, fjord-type estuaries, and tectonically caused estuaries. Each type is explained in detail and examples are given for each.

Oberrecht, Kenn

2007-01-30

239

In vitro biotransformation of decabromodiphenyl ether (BDE-209) and Dechlorane Plus flame retardants: a case study of ring-billed gull breeding in a pollution hotspot in the St. Lawrence River, Canada.  

PubMed

Decabromodiphenyl ether (deca-BDE) mixture (~97% of BDE-209) is now facing usage restrictions worldwide, which is leading to increased utilization of a series of alternative, replacement flame retardant (FR) products. Among these, Dechlorane Plus (DP) is receiving growing attention as this FR is increasingly being detected in wildlife samples, including birds from North America, Europe and Asia. Recent survey conducted in a known FR hotspot in the St. Lawrence River basin near Montreal (QC, Canada) revealed unexpectedly high detection frequencies and concentrations of BDE-209 and DP isomers (syn- and anti-DP) in the liver of breeding ring-billed gulls (Larus delawarensis) (RBGUs). Despite the global distribution of these current-use FRs, there is to our knowledge no study that has addressed the in vitro biotransformation of BDE-209 and DP isomers in birds. This study aimed at understanding the in vitro metabolism of BDE-209 and syn- and anti-DP using liver microsomes of Montreal-breeding RBGUs. Although BDE-15 (positive assay control) was consistently and positively depleted over the 90-min time frame of the in vitro assay, no depletion was observed for BDE-209 and DP isomers. These results suggest that CYP isoenzyme-mediated reductive dehalogenation of BDE-209 and DP is not likely to be a substantial metabolic pathway in RBGUs. However, investigations on deiodinases (expression, activity) should be considered in future studies as these enzymes have been suggested to be involved in the sequential debromination of BDE-209 in fish and human studies. High levels of BDE-209 determined in liver of RBGUs that strongly correlated with those of known or suggested BDE-209 debromination products (hepta- through nona-BDEs) may thus be indicative of concomitant dietary (e.g., fish consumption) and environmental exposure in the greater Montreal area, combined with poor or lack of metabolic capability toward these FRs. PMID:23542572

Chabot-Giguère, Bernice; Letcher, Robert J; Verreault, Jonathan

2013-05-01

240

Estuaries: Finding the Balance  

NSDL National Science Digital Library

Students can use this resource from the National Geographic to examine the conflict between development and the environment by focusing on estuaries across the United States. Its objectives are for students to learn about the environmental and economic importance of estuaries, consider the conflicts that arise because of the many uses of estuaries, research a specific estuary and the problems and solutions that have developed around it, and suggest compromises that might be made in order to protect both estuaries and economic development. To meet these objectives, students are directed to review a number of websites about estuaries and then to answer questions concerning environmental issues (e.g., What are the specific ecological characteristics of estuaries? What are some of the signs that an estuary is in trouble as a habitat?) and economic issues (e.g., How might proximity to major cities impact estuaries? To what degree should economic activity dictate the outcome of estuaries?).

Xpeditions NatGeo (National Geographic Society;)

2008-04-30

241

Eutrophication of the St. Lawrence Great Lakes  

USGS Publications Warehouse

Lakes Huron, Michigan, and Superior are classified as oligotrophic lakes on the basis of their biological, chemical, and physical characteristics. Lake Ontario, although rich in nutrients, is morphometrically oligotrophic or mesotrophic because of its large area of deep water. Lake Erie, the most productive of the lakes and the shallowest, is eutrophic. Several changes commonly associated with eutrophication in small lakes have been observed in the Great Lakes. These changes apparently reflect accelerated eutrophication in the Great Lakes due to man's activity. Chemical data compiled from a number of sources, dating as early as 1854, indicate a progressive increase in the concentrations of various major ions and total dissolved solids in all of the lakes except Lake Superior. The plankton has changed somewhat in Lake Michigan and the plankton, benthos, and fish populations of Lake Erie are greatly different today from those of the past. An extensive area of hypolimnetic water of Lake Erie has developed low dissolved oxygen concentrations in late summer within recent years.

Beeton, Alfred M.

1965-01-01

242

Attila Lawrence Professor  

E-print Network

. Courses taught: Undergraduate level History of Architectural Attila Lawrence Professor School of Architecture University of Nevada, Interior Architecture and Design, School of Architecture, University of Nevada

Hemmers, Oliver

243

Principal of Lawrence Catholic Academy Lawrence, MA  

E-print Network

. Lawrence Catholic Academy offers children age three through Grade 8 a challenging academic program that encourages the engagement of each student in the learning process while fostering a love for learning achievement and closing the achievement gap Providing leadership among faculty, staff, and parents

Huang, Jianyu

244

Revelations CallenderSt  

E-print Network

Franklin St James St S Glengall St Wellington St Athol St Howard St Amelia St Grosvenor Rd Albert St University Sq University St India St Ireton St Cromwell Rd Elm St Essex St PineSt Donegall Pass University St

Müller, Jens-Dominik

245

Three dimensional water quality modeling of a shallow subtropical estuary.  

PubMed

Knowledge of estuarine hydrodynamics and water quality comes mostly from studies of large estuarine systems. The processes affecting algae, nutrients, and dissolved oxygen (DO) in small and shallow subtropical estuaries are relatively less studied. This paper documents the development, calibration, and verification of a three dimensional (3D) water quality model for the St. Lucie Estuary (SLE), a small and shallow estuary located on the east coast of south Florida. The water quality model is calibrated and verified using two years of measured data. Statistical analyses indicate that the model is capable of reproducing key water quality characteristics of the estuary within an acceptable range of accuracy. The calibrated model is further applied to study hydrodynamic and eutrophication processes in the estuary. Modeling results reveal that high algae concentrations in the estuary are likely caused by excessive nutrient and algae supplies in freshwater inflows. While algal blooms may lead to reduced DO concentrations near the bottom of the waterbody, this study indicates that stratification and circulation induced by freshwater inflows may also contribute significantly to bottom water hypoxia in the estuary. It is also found that high freshwater inflows from one of the tributaries can change the circulation pattern and nutrient loading, thereby impacting water quality conditions of the entire estuary. Restoration plans for the SLE ecosystem need to consider both a reduction of nutrient loading and regulation of the freshwater discharge pattern. PMID:23122270

Wan, Yongshan; Ji, Zhen-Gang; Shen, Jian; Hu, Guangdou; Sun, Detong

2012-12-01

246

Regional Differences Among Estuaries  

NSDL National Science Digital Library

This text discusses differences in estuaries in different regions of the United States. It contrasts the fjord-like estuaries of the rocky Maine coast with the sandy barrier beaches, islands, and enclosed bays and sounds further south. The site also calls attention to the difference between the East Coast and the Northwest coast of emergence. The point is made that although they differ, all estuaries have great value and many are in danger.

Oberrecht, Kenn

2007-01-20

247

Regional Differences Among Estuaries  

NSDL National Science Digital Library

This text discusses differences in estuaries in different regions of the United States. It contrasts the fjord-like estuaries of the rocky Maine coast with the sandy barrier beaches, islands, and enclosed bays and sounds further south. The site also calls attention to the difference between the East Coast and the Northwest coast of emergence. The point is made that although they differ, all estuaries have great value and many are in danger.

248

Learning Lessons from Estuaries  

ERIC Educational Resources Information Center

There is something that draws all people to the sea and especially to the fertile estuaries that nuzzle up to its shores. An estuary serves as both a nursery and a grave for sea creatures. If life evolved from some primordial sea, it may well have been an estuary--a place where ocean and rivers meet and fresh and salty waters mingle in the…

Schnittka, Christine

2006-01-01

249

Linking Species Traits to the Abiotic Template of Flowing Waters: Contrasting Eco physiologies Underlie Displacement of Zebra Mussels by Quagga Mussels in a Large River-Estuary  

NASA Astrophysics Data System (ADS)

The St. Lawrence River-Estuary was the gateway of entry for dreissenids to North America and holds some of the oldest populations. The St. Lawrence also has four distinct physical-chemical water masses (a regional scale abiotic template) that both species inhabit. Despite their ecological similarities, quagga mussels are supplanting zebra mussels in much of their shared range. In order to try to better understand the changing distributions of these two species we compared glycogen, shell mass and tissue biomass in each of the water masses. This comparative physiological combined with experimental approaches (estuarine salinity experiments and reciprocal transplants) showed that while quagga mussels should dominate in most habitats, that abiotic/bioenergetic constraints in two regions (the Ottawa River plume and the freshwater-marine transition zone) might prevent them from dominating these locations. These findings are an example of how the interaction of landscape scale abiotic heterogeneity and a species-specific physiology can have strong impacts of distribution of biota large rivers.

Casper, A. F.

2005-05-01

250

The Stephen Lawrence Inquiry  

NSDL National Science Digital Library

In 1993, 18-year-old Stephen Lawrence was stabbed to death in London in a racially motivated attack. Lawrence's killers have not been successfully prosecuted, and, as this report released by the UK Home Office on February 24 reveals, the London police inquiry into the crime displayed "professional incompetence and institutional racism." Undoubtedly the most infamous racial murder in recent British history, Lawrence's death, the police investigation, and the far-reaching government inquiry which followed are being regarded as a milestone in British race relations, inspiring new private and government initiatives to improve relations as well as proposals for extensive changes in the UK policing and judicial systems. Users can read the full text of Sir William Macpherson's 352 page report at the UK Sationary Office site.

251

Nutrients in an Estuary  

NSDL National Science Digital Library

In this activity, learners model estuaries, artificially enriching both fresh and salt water samples with different amounts of nutrients and observing the growth of algae over several weeks. Learners relate their results to the phenomenon of algae blooms in estuaries. Learners then analyze data for different sites at the Guana Tolomato Matanzas National Estuarine Research Reserve (GTMNERR) in Florida to discover the relationships between nitrogen, chlorophyll, and dissolved oxygen. Finally, learners study how nutrients cycle through an estuary and suggest recommendations for reducing nutrient inputs to estuary waters.

Terc; National Oceanic and Atmospheric Administration (NOAA)

2012-06-26

252

HAMILTON ST HAMILTON ST  

E-print Network

PROSPERST SICARD ST LAFAYETTE ST BISHO P PL MINEST UNION ST SEM INARY PL COLLEGE AVE COLLEGE AVE GEORGE ST Queens Heldrich Plaza College of Nursing Institute for Health, Health Care Policy, and Aging Research Center Miller Hall McKinney Hall Italian House Alexander Johnston Hall Global Programs 36 Union Street

Hanson, Stephen José

253

LBNL-6288E ERNEST ORLANDO LAWRENCE  

E-print Network

1 LBNL-6288E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Lawrence Berkeley National Laboratory Reprint version of journal article Energy Technologies Division, Lawrence Berkeley National Laboratory, One Cyclotron

254

National Estuary Program  

NSDL National Science Digital Library

Estuaries are places where rivers meet the sea and are critical to the health of coastal environments and our enjoyment of them. Website features abundant information on the legal and scientific aspects of estuary preservation. Includes guidelines, program profiles, and a shorter version in Spanish. Resources for teachers and students include games and activities. External links to additional programs also provided.

255

Sex alteration in soft-shell clams ( Mya arenaria) in an intertidal zone of the Saint Lawrence River (Quebec, Canada)  

Microsoft Academic Search

The purpose of this study was to verify whether any changes in sex ratio might occur in soft-shell clams (Mya arenaria) located in an intertidal harbor zone located at the mouth of the Saguenay Fjord in the Saint Lawrence estuary (Baie Sainte-Catherine (BSC), Québec, Canada) likely to be contaminated by organotin compounds. Bivalves were harvested at the BSC harbor site

F Gagné; C Blaise; J Pellerin; E Pelletier; M Douville; S Gauthier-Clerc; L Viglino

2003-01-01

256

Decline of Canada geese (Branta canadensis) and common goldeneye (Bucephala clangula) associated with a collapse of eelgrass (Zostera marina) in a Nova Scotia estuary  

NASA Astrophysics Data System (ADS)

Mean numbers of migrant Canada geese (Branta canadensis) in Antigonish Harbour in the southern Gulf of St. Lawrence (Canada) during October to December were similar (approx. 450-500 birds) for the period 1998-2000. Similarly, during this period, geese used two foraging sites. However, in 2001, the average number of birds decreased by half and the primary foraging sites were used only rarely. This coincided with a decline of about 95% in the biomass of roots and rhizomes of eelgrass (Zostera marina) that occurred between October 2000 and 2001. Eelgrass is the principal food of geese in this estuary. In addition, there was a reduction of around 50% in the numbers of common goldeneye (Bucephala clangula), which feed on invertebrates associated with eelgrass. Lower than usual weekly abundances of geese and goldeneye are probably the result of an unusually short residence time in the estuary, rather than a decline in the total number of visiting migrants. We attribute these changes in the distribution and abundance of geese and goldeneyes to the dramatic decline in eelgrass.

Seymour, Norman; Miller, Anthony; Garbary, David

2002-08-01

257

Estuarine Science: All About Estuaries  

NSDL National Science Digital Library

Estuaries are partially enclosed bodies of water along coastlines where fresh water and salt water meet and mix. They act as a transition zone between oceans and continents. This site examines various aspects of estuaries, focusing on the geological features that make an estuary, as well as the water circulation patterns by which they are classified. It also has a section that allows the user to access additional text and graphics on many of the estuaries of the world.

258

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-254E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY ALDEHYDE AND OTHER VOLATILE ORGANIC of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;LBNL Environment Department Environmental Energy Technologies Division Lawrence Berkeley National Laboratory

259

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2002 Volume II July 2003 Ernest Orlando Lawrence Berkeley National Laboratory Prepared

260

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2002 Volume I JULY 2003 Ernest Orlando Lawrence Berkeley National Laboratory Prepared

261

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-6607E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Measurement-Based Evaluation. Singer Environmental Energy Technologies Division Lawrence Berkeley National Laboratory April 3, 2014 thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National

262

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-6349E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Assessing the Costs and Benefits Division Lawrence Berkeley National Laboratory Ridah Sabouni and Tracy Evans Energetics Incorporated Paul Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. Acknowledgment This work

263

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Environment, Health, and Safety Division of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2004 Volume I SEPTEMBER 2005 Ernest Orlando Lawrence Berkeley National Laboratory

264

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Environment, Health, and Safety Division of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2004 Volume II SEPTEMBER 2005 Ernest Orlando Lawrence Berkeley National Laboratory

265

Lawrence Berkeley National Laboratory  

NSDL National Science Digital Library

Arguably the most famous government research laboratory in the United States, the Lawrence Berkeley National Laboratory is supported by the U.S. Department of Energy and managed by the University of California. Scientists associated with the laboratory have received a number of accolades over the years, including 13 Nobel Prizes and 13 National Medals of Science. The materials on the site are divided into five primary sections, including About the Lab, For Staff and Guests, and Visitor's Guide. First-time users may wish to start with the News Center. Here they can read press releases and features, and watch videos of scientists talking about their work. The Video Glossary contains wonderful clips of scientists talking about atmospheric aerosols, energy efficiency, and myriad other topics. The general public won't want to miss the "$ Ways to Save Money on Energy" section and the equally compelling area on Globally Transformative Technologies. The site is rounded out by a place where visitors can follow the Laboratory's activities via Facebook, Twitter, and YouTube.

266

THREE-DIMENSIONAL MODELING OF COHESIVE SEDIMENT TRANSPORT IN A PARTIALLY STRATIFIED MICRO-TIDAL ESTUARY TO ASSESS EFFECTIVENESS OF SEDIMENT TRAPS  

EPA Science Inventory

The three-dimensional (3D) finite difference model Environmental Fluid Dynamics Code (EFDC) was used to simulate the hydrodynamics and sediment transport in a partially stratified micro-tidal estuary. The estuary modeled consisted of a 16-km reach of the St. Johns River, Florida,...

267

Estuary Restoration Act Estuary Habitat Restoration Council  

E-print Network

. Recommend USACE fund. 3. St. Lucie River Oyster Reef Will restore and monitor 2 acres of oyster reef. Little Oyster Creek Will restore 10 acres of oyster habitat using Ultra Balls and Sanctuary, NC Reef stream restoration activities. Recommend NOOA fund. 11. Scaling-Up Native Oyster Will restore 4 acres

US Army Corps of Engineers

268

Ecology of estuaries  

SciTech Connect

This book is a summary of information available on estuarine ecology, that reviews concepts and problems of estuaries and assesses the value of these coastal systems. It investigates such topics as water circulation and mixing, trace elements, nutrients, organic matter, and sedimentary processes, with reviews on more than two decades of intense study. Chapters reflect contributions from a variety of interdisciplinary sciences including botany, chemistry, ecology, geology, physics, and zoology.

Kennish, M.J.

1986-01-01

269

AN ECONOMIC EVALUATION OF THE ST. LAWRENCE RIVER-EASTERN  

E-print Network

River-eastern Lake Ontario bass fishery has long been known as one of the finest sport fisheries-eastern Lake Ontario bass fishery to licensed New York resi- dent anglers. Benefits to out-of-state anglers included in this study. In addition, general recreational benefits of the fishery to tourists and others

270

Estuaries are not so unique  

Microsoft Academic Search

The applicability of recent theories relating tides and river flow to estuarine bathymetry has been assessed against observations from UK estuaries. These theories, combined with observations, show that variations between estuaries are limited by how tides and river flow control sediments and bathymetry. Typical ages were determined from differences between theoretical and observed depths for Rias (11000 years), Coastal Plain

David Prandle; Andrew J. Manning

2005-01-01

271

Deborah Lawrence, CV January 2013 1 DEBORAH LAWRENCE  

E-print Network

, VA 22904-4123 (ph) 434-924-0581 (fax) 434-982-2137 lawrence@virginia.edu EDUCATION Ph. D. May 1998. Reproductive effort and nutrient availability affect resorption in a Costa Rican rainforest. Ecology. 2. *Das R. 2012. Trees, not organic fertilizers, minimize nutrient loss from coffee management systems

Lawrence, Deborah

272

Lawrence CV 1 Shawn A. Lawrence, PhD, LCSW  

E-print Network

consumption, tailgating, and negative consequences. Journal of Child & Adolescent Substance Abuse Lawrence, S of Arts in Psychology State University of New York at Buffalo, Buffalo New York Research Focus: Program Evaluation Obesity and Stigmatization in adults and Children Determinants of Physical Activity in Children

Van Stryland, Eric

273

Monitoring and Managing Water Quality in the San Francisco Estuary San Francisco Estuary Institute and the  

E-print Network

Monitoring and Managing Water Quality in the San Francisco Estuary San Francisco Estuary Institute and the Regional Monitoring Program for Water Quality in the San Francisco Estuary #12;www.sfei.org #12;Contribution 517 Monitoring and Managing Water Quality in the San Francisco Estuary San Francisco Estuary

274

Grounded Cognition Lawrence W. Barsalou  

E-print Network

as a Review in Advance on August 15, 2007 The Annual Review of Psychology is online at httpGrounded Cognition Lawrence W. Barsalou Department of Psychology, Emory University, Atlanta://psych.annualreviews.org This article's doi: 10.1146/annurev.psych.59.103006.093639 Copyright c 2008 by Annual Reviews. All rights

Coulson, Seana

275

MEMORIAL RESOLUTION LAWRENCE R. BLINKS  

E-print Network

College and while there he spent a summer at the University of Michigan's field station at Douglas Lake of the beginnings of biology as an experimental science in America. Born in 1900 in Michigan City, Indiana, Lawrence of Michigan had a tremendous impact on him and set him thinking about biology as a career path. He transferred

276

MDLBased ContextFree Graph Grammar Induction Istvan Jonyer, Lawrence B. Holder and Diane J. Cook  

E-print Network

MDL­Based Context­Free Graph Grammar Induction Istvan Jonyer, Lawrence B. Holder and Diane J. Cook Department of Computer Science and Engineering University of Texas at Arlington Box 19015 (416 Yates St­ theoretic approach, or expression approach (Nagl 1987). Here a graph is a pair of sets G = #V, E where V

Holder, Lawrence B.

277

A detailed magnetic survey of the Saint Lawrence River: Oak Point to Lake Ontario, New York  

Microsoft Academic Search

Measurements of the total intensity of the Earth's magnetic field in the St. Lawrence River between Oak Point and Lake Ontario indicated magnetic anomalies of high magnitude and steep gradients due to rocks of varying magnetic susceptibility in the Precambrian basement complex. The anomalies and magnetic contours that trend continuously across the river indicated no large lateral offset in this

F. Revetta; J. Cardinal

1979-01-01

278

Organotins in Zebra Mussels ( Dreissena polymorpha) from the Saint Lawrence River  

Microsoft Academic Search

Toxic antifouling compounds such as organotins have been released in the aquatic ecosystems throughout the world and can be bioaccumulating in biota. The purpose of this study was to assess the use of zebra mussels (Dreissena polymorpha) as a biomonitor for investigating the geographical variations of organotin bioavailability along the St. Lawrence River. The presence of organotins (tributyltins (TBT) and

Lidia Regoli; Hing Man Chan; Yves de Lafontaine

1999-01-01

279

Session III: Estuary Columbia River Estuary overview of physical features and habitats  

E-print Network

and river flow. About 71% of the lower estuary is deep. Temperatures in the estuary vary with depth the wetland plants is the basis for the food web in the estuary, supplemented by algal production from

280

LAWRENCE BERKELEY NATIONAL LABORATORY REPORT NO. LBNL-59202 ERNEST ORLANDO LAWRENCE  

E-print Network

LAWRENCE BERKELEY NATIONAL LABORATORY REPORT NO. LBNL- 59202 ERNEST ORLANDO LAWRENCE BERKELEY of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;LAWRENCE BERKELEY NATIONAL LABORATORY REPORT NO. LBNL- 59202 Air Tightness of US Homes: Model Development1

281

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory LBL-27170 (2007) Volume I Site Environmental of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2006 Volume 1 September 2007 Ernest Orlando Lawrence Berkeley National Laboratory

282

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory January 4, 2013 State of California Office, MS76-225 Berkeley, California 94720 #12;#12;1 Ernest Orlando Lawrence Berkeley National Laboratory projects and activities managed or led by the University of California Lawrence Berkeley National

Eisen, Michael

283

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-4143E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Power and Frequency Control a subcontract administered by the Lawrence Berkeley National Laboratory, which is operated by the University of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Power

McCalley, James D.

284

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory LBL-27170 (2009) Volume I Site Environmental of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2008 Volume I September 2009 Ernest Orlando Lawrence Berkeley National Laboratory

285

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory LBL-27170 (2008) Volume I Site Environmental of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2007 Volume 1 September 2008 Ernest Orlando Lawrence Berkeley National Laboratory

286

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July Orlando Lawrence Berkeley National Laboratory Prepared for the U.S. Department of Energy under Contract thereof or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National

287

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory LBL-27170 (2009) Volume II Site Environmental of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2008 Volume II September 2009 Ernest Orlando Lawrence Berkeley National Laboratory

288

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July Ernest Orlando Lawrence Berkeley National Laboratory Prepared for the U.S. Department of Energy under thereof or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National

289

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory LBL-27170 (2008) Volume II Site Environmental of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2007 Volume II September 2008 Ernest Orlando Lawrence Berkeley National Laboratory

290

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-62078 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Air Leakage of U.S. Homes: Model of the University of California or any other sponsor. Ernest Orlando Lawrence Berkeley National Laboratory of the ventilation used to control IAQ. The Lawrence Berkeley National Laboratory has been gathering residential air

291

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory LBL-27170 (2007) Volume II Site Environmental of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2006 Volume II September 2007 Ernest Orlando Lawrence Berkeley National Laboratory

292

Lawrence Livermore National Laboratory Internships  

NSDL National Science Digital Library

Lawrence Livermore National Laboratory Internships -- The Lawrence Livermore National Laboratory (LLNL) hosts 300 to 400 undergraduate and graduate students and some faculty every summer in support of its world-class scientific facilities and staff and in an effort to help train the nation's next generation of scientists and engineers. Involvement in world-class research provides participants with a set of experiences that support their education and career goals. Typically, participants gain hands-on experience and the opportunity to apply learned theory to real life problems. An experience of this type, and with these resources at a premier state-of-the-art research laboratory is not available in an academic research lab.

293

Seasonal dissolved inorganic nitrogen and phosphorus budgets for two sub-tropical estuaries in south Florida, USA  

NASA Astrophysics Data System (ADS)

Interactions among watershed nutrient loading, circulation, and biogeochemical cycling determine the capacity of estuaries to accommodate introduced nutrients. Baseline quantification of loading, flushing time, export, and internal processes is essential to understand responses of sub-tropical estuaries to variable climate and nutrient loading. The goal of this study was to develop seasonal dissolved inorganic nitrogen (DIN) and phosphorus (DIP) budgets for the two estuaries in south Florida, the Caloosahatchee River Estuary (CRE) and the St. Lucie Estuary (SLE), from 2002-2008 spanning various climatic conditions. The Land Ocean Interactions in the Coastal Zone (LOICZ) Biogeochemical Model was used to generate water, salt, and (DIN and DIP) budgets. The predicted increase in internal DIN production for the CRE vs. the SLE was associated with increased external DIN loading. Water column DIN concentrations decreased and stabilized in both estuaries as flushing time increased to > 10 d. The CRE demonstrated heterotrophy or balanced metabolism across all seasonal budgets. Although the SLE was also sensitive to DIN loading, system autotrophy and net ecosystem metabolism increased with DIP loading to this estuary. This included a huge DIP consumption and bloom of a cyanobacterium (Microcystis aeruginosa) following hurricane-induced discharge in 2005. Additionally, while denitrification offered a loss pathway for inorganic nitrogen in the CRE, this potential was not evident for the smaller and more anthropogenically altered St. Lucie Estuary. Disparities between total and inorganic loading ratios suggested that management actions should examine the role of dissolved organic nitrogen (DON) in attempts to reduce both nitrogen and phosphorus inputs to the SLE. Establishment of quantitative loading limits for anthropogenically impacted estuaries requires an understanding of the inter-seasonal and inter-annual relationships for both N and P, circulation and flushing, variability in plankton community composition, and the dynamics of DON.

Buzzelli, C.; Wan, Y.; Doering, P. H.; Boyer, J. N.

2013-02-01

294

PECONIC ESTUARY EELGRASS HABITAT CRITERIA STUDY  

EPA Science Inventory

PECONIC ESTUARY EELGRASS HABITAT CRITERIA STUDY The main objective of this study is to develop criteria for eelgrass habitat establishment and persistence within the Peconic Estuary utilizing various environmental analyses. The Program evaluated water and sediment quality data to...

295

Estuaries and Clean Water Act of 2000  

NSDL National Science Digital Library

The Office of Water at the Environmental Protection Agency has posted online this document on the new Estuaries and Clean Water Act of 2000. Available in .pdf format, the document summarizes the Act, which emphasizes restoration of estuary habitat.

296

Lawrence University: Images & Digital Collections  

NSDL National Science Digital Library

Appleton, WisconsinâÂÂs, Lawrence University continues to work diligently to digitize its library holdings that might be of interest to the general public. These collections include items from the department of theatre arts, along with items from Lux, the online home for the universityâÂÂs scholarly and creative works. It's a great way to learn about some of its most compelling projects, including wonderful honor projects, such as "Learning from Experience: A Philosophical Perspective." Moving on, the theatre arts area contains images, programs and other bits of ephemera from shows like Cabaret, Cinderella, and much more.

297

Lawrence Berkeley National Laboratory: VISTA  

NSDL National Science Digital Library

A very comprehensive and well-organized offering from Lawrence Berkeley National Laboratory, VISTA offers "suite of programs and databases for comparative analysis of genomic sequences. There are two ways of using VISTA - you can submit your own sequences and alignments for analysis (VISTA servers) or examine pre-computed whole-genome alignments of different species (VISTA browser)." The site also offers up-to-date updates on genomic sequences. Included in the April 2004 update are the Human-Chimpanzee, Human-Chicken, and D.melanogaster-Honey Bee whole genome alignments. VISTA is definitely a site for researchers and students involved in genomic research.

298

Estuaries: Where Rivers Meet the Sea  

NSDL National Science Digital Library

Take your students on an EstuaryLive telecast! EstuaryLive brings free, live internet field trips in four different estuaries around the country, right to your classroom. These online field trips are the next best thing to an actual trip to an estuary, providing students with an exciting and new way to learn about unique estuarine ecosystems. The site also includes archived webcasts and teacher resources including classroom activities and a glossary.

2011-05-16

299

Estuaries: Where Rivers Meet the Sea  

NSDL National Science Digital Library

Take your students on an EstuaryLive telecast! EstuaryLive brings free, live internet field trips in four different estuaries around the country, right to your classroom. These online field trips are the next best thing to an actual trip to an estuary, providing students with an exciting and new way to learn about unique estuarine ecosystems. The site also includes archived webcasts and teacher resources including classroom activities and a glossary.

300

Hydrogen Storage atHydrogen Storage at Lawrence Berkeley National LaboratoryLawrence Berkeley National Laboratory  

E-print Network

Hydrogen Storage atHydrogen Storage at Lawrence Berkeley National LaboratoryLawrence Berkeley National Laboratory Presentation at thePresentation at the Hydrogen Storage Grand ChallengeHydrogen Storage

301

PECONIC ESTUARY STORMWATER ASSESSMENT AND PLANNING TOOL  

EPA Science Inventory

PECONIC ESTUARY STORMWATER ASSESSMENT AND PLANNING TOOL Horsley & Witten, Inc. was contracted by the Peconic Estuary Program to create a Regional Stormwater Runoff Management Plan designed to mitigate loadings of fecal coliform bacteria and nitrogen to the Peconic Estuary. The pu...

302

Lawrence Livermore National Laboratory 2007 Annual Report  

SciTech Connect

Lawrence Livermore National Laboratory's many outstanding accomplishments in 2007 are a tribute to a dedicated staff, which is shaping the Laboratory's future as we go through a period of transition and transformation. The achievements highlighted in this annual report illustrate our focus on the important problems that affect our nation's security and global stability, our application of breakthrough science and technology to tackle those problems, and our commitment to safe, secure, and efficient operations. In May 2007, the Department of Energy (DOE) awarded Lawrence Livermore National Security, LLC (LLNS), a new public-private partnership, the contract to manage and operate the Laboratory starting in October. Since its inception in 1952, the Laboratory had been managed by the University of California (UC) for the DOE's National Nuclear Security Administration (NNSA) and predecessor organizations. UC is one of the parent organizations that make up LLNS, and UC's presence in the new management entity will help us carry forward our strong tradition of multidisciplinary science and technology. 'Team science' applied to big problems was pioneered by the Laboratory's co-founder and namesake, Ernest O. Lawrence, and has been our hallmark ever since. Transition began fully a year before DOE's announcement. More than 1,600 activities had to be carried out to transition the Laboratory from management by a not-for-profit to a private entity. People, property, and procedures as well as contracts, formal agreements, and liabilities had to be transferred to LLNS. The pre-transition and transition teams did a superb job, and I thank them for their hard work. Transformation is an ongoing process at Livermore. We continually reinvent ourselves as we seek breakthroughs that impact emerging national needs. An example is our development in the late 1990s of a portable instrument that could rapidly detect DNA signatures, research that started with a view toward the potential threat of terrorist use of biological weapons. As featured in our annual report, activities in this area have grown to many important projects contributing to homeland security and disease prevention and control. At times transformation happens in large steps. Such was the case when nuclear testing stopped in the early 1990s. As one of the nation's nuclear weapon design laboratories, Livermore embarked on the Stockpile Stewardship Program. The objectives are to ensure the safety, security, and reliability of the nation's nuclear weapons stockpile and to develop a science-based, thorough understanding of the performance of nuclear weapons. The ultimate goal is to sustain confidence in an aging stockpile without nuclear testing. Now is another time of major change for the Laboratory as the nation is resizing its nuclear deterrent and NNSA begins taking steps to transform the nuclear weapons complex to meet 21st-century national security needs. As you will notice in the opening commentary to each section of this report, the Laboratory's senior management team is a mixture of new and familiar faces. LLNS drew the best talent from its parent organizations--Bechtel National, UC, Babcock & Wilcox, the Washington Group Division of URS, and Battelle--to lead the Laboratory. We are honored to take on the responsibility and see a future with great opportunities for Livermore to apply its exceptional science and technology to important national problems. We will work with NNSA to build on the successful Stockpile Stewardship Program and transform the nation's nuclear weapons complex to become smaller, safer, more secure, and more cost effective. Our annual report highlights progress in many relevant areas. Laboratory scientists are using astonishing computational capabilities--including BlueGene/L, the world's fastest supercomputer with a revolutionary architecture and over 200,000 processors--to gain key insights about performance of aging nuclear weapons. What we learn will help us sustain the stockpile without nuclear testing. Preparations are underway to start experiments at

Chrzanowski, P; Walter, K

2008-04-25

303

Assessing the application of an airborne intensified multispectral video camera to measure chlorophyll a in three Florida estuaries  

SciTech Connect

After absolute and spectral calibration, an airborne intensified, multispectral video camera was field tested for water quality assessments over three Florida estuaries (Tampa Bay, Indian River Lagoon, and the St. Lucie River Estuary). Univariate regression analysis of upwelling spectral energy vs. ground-truthed uncorrected chlorophyll a (Chl a) for each estuary yielded lower coefficients of determination (R{sup 2}) with increasing concentrations of Gelbstoff within an estuary. More predictive relationships were established by adding true color as a second independent variable in a bivariate linear regression model. These regressions successfully explained most of the variation in upwelling light energy (R{sup 2}=0.94, 0.82 and 0.74 for the Tampa Bay, Indian River Lagoon, and St. Lucie estuaries, respectively). Ratioed wavelength bands within the 625-710 nm range produced the highest correlations with ground-truthed uncorrected Chl a, and were similar to those reported as being the most predictive for Chl a in Tennessee reservoirs. However, the ratioed wavebands producing the best predictive algorithms for Chl a differed among the three estuaries due to the effects of varying concentrations of Gelbstoff on upwelling spectral signatures, which precluded combining the data into a common data set for analysis.

Dierberg, F.E. [DB Environmental Labs., Inc., Rockledge, FL (United States); Zaitzeff, J. [National Oceanographic and Atmospheric Adminstration, Washington, DC (United States)

1997-08-01

304

Future variability of solute transport in a macrotidal estuary  

NASA Astrophysics Data System (ADS)

The physical controls on salt distribution and river-sourced conservative solutes, including the potential implications of climate change, are investigated referring to model simulations of a macrotidal estuary. In the UK, such estuaries typically react rapidly to rainfall events and, as such, are often in a state of non-equilibrium in terms of solute transport; hence are particularly sensitive to climate extremes. Sea levels are projected to rise over the 21st century, extending the salinity maximum upstream in estuaries, which will also affect downstream solute transport, promoting estuarine trapping and reducing offshore dispersal of material. Predicted 'drier summers' and 'wetter winters' in the UK will influence solute transport further still; we found that projected river flow climate changes were more influential than sea-level rise, especially for low flow conditions. Our simulations show that projected climate change for the UK is likely to increase variability in estuarine solute transport and, specifically, increase the likelihood of estuarine trapping during summer, mainly due to drier weather conditions. Future changes in solute transport were less certain during winter, since increased river flow will to some extent counter-act the effects of sea-level rise. Our results have important implications for non-conservative nutrient transport, water quality, coastal management and ecosystem resilience.

Robins, Peter E.; Lewis, Matt J.; Simpson, John H.; Howlett, Eleanor R.; Malham, Shelagh K.

2014-12-01

305

Ecology of estuaries: Anthropogenic effects  

SciTech Connect

Estuaries and near-shore oceanic water are subjected to a multitude of human wastes. The principal objective of this book is to examine anthropogenic effects on estuaries, and it focuses primarily on contaminants in coastal systems. Covered within various chapters are the following topics: waste disposal strategies; definition and classification of pollutants (including organic loading, oil pollution, polynuclear aromatic hydrocarbons; chlorinated hydrocarbons; heavy metals; radionuclides) biological impacts; waste management; impacts of power plants; dredging and spoil disposal; case studies, primarily Chesapeake Bay. The book serves as a text and as a reference.

Kennish, M.J.

1992-01-01

306

LAWRENCE RISK-BASED AIR SCREENING  

EPA Science Inventory

The pediatric asthma rate in the city of Lawrence is the highest in the state of Massachusetts. This project will evaluate whether the cumulative risks due to the air pollution in Lawrence is contributing to the high asthma rates and other respiratory problems. The project will...

307

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 54767 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Duct Tape Durability Testing M.H. Sherman and I.S. Walker Environmental Energy Technologies Division April 2004 This work was supported of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. Legal

308

Wolfgang Langhans Lawrence Berkeley National Laboratory  

E-print Network

Wolfgang Langhans Lawrence Berkeley National Laboratory Earth Science Division 1 Cyclotron Road 84R Professional experience Jan 2013 ­ present Postdoctoral fellow, Lawrence Berkeley National Laboratory, Berkeley0171 Berkeley, CA 94720-8268 Phone: (510) 486-7175 Fax: (510) 486-7775 Email: wlanghans

Ajo-Franklin, Jonathan

309

LAWRENCE BERKELEY NATIONAL LABORATORY About Berkeley Lab  

E-print Network

LAWRENCE BERKELEY NATIONAL LABORATORY About Berkeley Lab Berkeley Lab is a U.S. Department of Energy (DOE) national laboratory that conducts a wide variety of unclassified scientific research for DOE and energy research. Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who

Eisen, Michael

310

CCD DEVELOPMENT PROGRESS AT LAWRENCE BERKELEY NATIONAL  

E-print Network

CCD DEVELOPMENT PROGRESS AT LAWRENCE BERKELEY NATIONAL LABORATORY W. F. Kolbe, S. E. Holland and C. J. Bebek Lawrence Berkeley National Laboratory Abstract P-channel CCD imagers, 200-300 µm thick. INTRODUCTION We have developed fully depleted, back-illuminated CCD imagers fabricated on high-resistivity, n

311

A historical review and bibliometric analysis of research on estuary pollution.  

PubMed

A bibliometric method based on Science Citation Index-Expanded published by the Thomson Reuters was used to quantitatively assess the global estuary pollution research from 1991 to 2010. The main results were as follows: there had been a notable growth trend in publication outputs. Marine Pollution Bulletin was the most active journal. Environmental sciences were top popular subject categories. USA produced the most single, internationally collaborative, first authored and corresponding authored articles. The Chinese Academy of Sciences was the most productive institute for the total articles. Sediment was the most active research topic, which ranked 1st in article title, article abstract, author keyword, and KeyWords Plus analysis, respectively. Heavy metals received stable focus on a high degree in the field of estuary pollution research. Mostly refractory organic compounds (e.g. PAHs) became more active. Biomarkers and bioaccumulation both were active issues. Eutrophication of estuarine waters receives increasing concern in estuary pollution research. PMID:22119413

Sun, Jinshui; Wang, Ming-Huang; Ho, Yuh-Shan

2012-01-01

312

Lawrence Berkeley National Laboratory Center for Computational Sciences and Engineering  

E-print Network

' & $ % Lawrence Berkeley National Laboratory Center for Computational Sciences and Engineering Beckner Center for Computational Sciences and Engineering Lawrence Berkeley National Laboratory Keith­in­Progress Poster, 26th International Symposium on Combustion #12; ' & $ % Lawrence Berkeley National Laboratory

313

Osni A. Marques Lawrence Berkeley National Laboratory phone: (510) 4865290  

E-print Network

Osni A. Marques Lawrence Berkeley National Laboratory phone: (510) 4865290 1 Cyclotron Road Laboratory, 2003 Computer Systems Engineer III, Lawrence Berkeley National Laboratory, 19962003 Assistant University of Londrina, Brazil, 1983 Professional Experience Staff Scientist, Lawrence Berkeley National

Marques, Osni

314

From Berkeley Lab to the Marketplace Lawrence Berkeley National Laboratory  

E-print Network

From Berkeley Lab to the Marketplace Smart Lawrence Berkeley National Laboratory Technology Transfer with Partner #12;Berkeley Lab Lawrence Berkeley National Laboratory Technology Transfer at Berkeley Lab Partnering with Lawrence Berkeley National Laboratory, also known as Berkeley Lab, is located

Eisen, Michael

315

14. Historic American Buildings Survey PHOTOCOPY OF EVERETT MILLS, LAWRENCE, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. Historic American Buildings Survey PHOTOCOPY OF EVERETT MILLS, LAWRENCE, MASS., INSURANCE SURVEY DRAWING n. d. From the collection of Factory Mutual Insurance Company, Norwood, Mass. - Lawrence Machine Shop, Union & Canal Streets, Lawrence, Essex County, MA

316

MDL-Based Context-Free Graph Grammar Induction Istvan Jonyer, Lawrence B. Holder and Diane J. Cook  

E-print Network

MDL-Based Context-Free Graph Grammar Induction Istvan Jonyer, Lawrence B. Holder and Diane J. Cook Department of Computer Science and Engineering University of Texas at Arlington Box 19015 (416 Yates St- theoretic approach, or expression approach (Nagl 1987). Here a graph is a pair of sets G = V, E where V

Holder, Lawrence B.

317

Monthly water balance in tributary watersheds of the Great Lakes Saint Lawrence River basin as influenced by climatic factors  

Microsoft Academic Search

SUMMARY: We observe in this basin the variation of the climate from pure oceanic at the Atlantic shores to continental at the west shores of Lake Michigan and the west extremity of Lake Superior. The type of hydrology generated by tributaries to the Great Lakes and to the St. Lawrence River is Lhe product of the climate dominating the tributary

Boris S. Browzin

318

Quantified Analysis of the Probability of Flooding in the Thames Estuary under Imaginable Worst-case Sea Level Rise Scenarios  

Microsoft Academic Search

Most studies of the impacts of sea level rise (SLR) have explored scenarios of < 1 m during the 21st century, even though larger rises are possible. This paper takes a different approach and explores and quantifies the likely flood impacts in the Thames estuary for a number of plausible, but unlikely, SLR scenarios. The collapse of the Western Antarctic Ice

R. J. DAWSON; J. W. HALL; P. D. BATES; R. J. NICHOLLS

2005-01-01

319

The Value of Healthy Estuaries  

NSDL National Science Digital Library

The article explores why healthy estuaries are critical to humans and wildlife: supporting both commercial and recreational fisheries, treating waste and runoff, protecting coastal areas from natural hazards, connect bodies of water for transportation, and nurturing a balance of the food web

Robert Christian (East Carolina University;)

2009-03-15

320

The Value of Healthy Estuaries  

NSDL National Science Digital Library

Healthy estuaries are critical to humans and wildlife. They provide food, supporting both commercial and recreational fisheries, treat waste and runoff to maintain water quality, protect coastal areas from natural hazards, connect bodies of water for transportation and marine operations, and nurture a balance of the food web upon which all life depends.

Robert Christian (Thomas Harriot College of Arts and Sciences;)

2009-03-22

321

Simulated Sampling of Estuary Plankton  

ERIC Educational Resources Information Center

To find out about the microscopic life in the valuable estuary environment, it is usually necessary to be near the water. This dry lab offers an alternative, using authentic data and a simulation of plankton sampling. From the types of organisms found in the sample, middle school students can infer relationships in the biological and physical…

Fortner, Rosanne W.; Jenkins, Deborah Bainer

2009-01-01

322

Macrobenthos composition, distribution and abundance within Sungai Pulai estuary, Johor, Malaysia  

NASA Astrophysics Data System (ADS)

Macrobenthos are very useful organisms for monitoring marine environmental and widely use in marine ecology research. They are able to monitor the difference phase in the recovery stage of disturbed sites by appear different species macrobenthos after the cessation of the impact. Univariate and multivariate methods were use to study the macrobenthos community within Sungai Pulai estuary, Johor, Malaysia. Five sub-samples were taken at each sampling sites by using 10 cm diameter corer. Crustaceans were the most abundant at Tanjung Adang (St. 1) and the station of non-seagrass area (St. 2) while polychaetes were the most abundant at Merambong Shoal (St. 3). Higher density of macrobenthos was found at St.3 followed by St. 1 and St. 2. The commonly used population indices such as diversity, richness, evenness and dominance were employed to determine the differences in diversity and abundance of macrobenthos. The diversity, richness and evenness index values showed slight increment from Station 1 to Station 3, while the dominance index decreasing trend from Station 1 to Station 3. A total 21 polychaete families were collected in Sungai Pulai estuary, which was dominated by the Spionidae, Capitellidae and Glyceridae. Cluster (Bray-Curtis similarities) analyses revealed that the Tanjung Adang and Merambong Shoal population were clearly separated from the station non-seagrass. For the time being factors that influence the pattern of distribution of the macrobenthos cannot be determined and subjected to further studies.

Shi, Guan Wan; Min, Lee Di; Ghaffar, Mazlan Abd; Ali, Masni Md; Cob, Zaidi Che

2014-09-01

323

75 FR 34975 - Notice of Estuary Habitat Restoration Council's Intent to Revise its Estuary Habitat Restoration...  

Federal Register 2010, 2011, 2012, 2013

...Policy task force goals and in identifying focus areas for the estuary habitat restoration strategy, such as: climate adaptation restoration, socio-economic benefits of estuary habitat restoration, and geographic restoration...

2010-06-21

324

MAPPING BATHYMETRY AND BOTTOM TYPE IN A SHALLOW ESTUARY  

EPA Science Inventory

Bathymetry and bottom type are important in characterizing estuaries and their ecology but hard to map, especially in shallow estuaries. Acoustic backscattering was used to remotely sense these properties in the shallow Slocums River Estuary of Massachusetts. Acoustic pulses were...

325

Comparison of Nutrient Drivers and Response Metrics in Oregon Estuaries  

EPA Science Inventory

With the goal of assessing sensitivity to nutrient enrichment, we present a cross-estuary comparison of nutrient sources, levels, and biological responses (phytoplankton and macroalgae) for thirteen Oregon estuaries. Nitrogen levels in the upstream portions of the estuaries are ...

326

St. Louis  

Cancer.gov

The Psychology Department of St. Louis Children’s Hospital at Washington University Medical Center is pleased to recruit for a second Postdoctoral Fellowship position in Pediatric Psychology beginning September 2014. With a balance of in-depth and broad based training experiences, this one-year program will prepare fellows to work independently in the practice of pediatric psychology.

327

Journal of Engineering Mathematics Optimal discharging in a branched estuary Optimal discharging in a branched estuary  

E-print Network

Journal of Engineering Mathematics Optimal discharging in a branched estuary Optimal discharging for the optimal discharge rate. If cross-sectional mixing within each branch of the estuary takes place more in a branched estuary R. SMITH Department of Mathematical Sciences, Loughborough University, LE11 3TU, U.K. e

328

Morphology, hydrography and sediment dynamics in a mangrove estuary: The Konkoure Estuary, Guinea  

Microsoft Academic Search

The Konkouré Estuary in the Republic of Guinea is a poorly understood atypical mangrove system. Sediment dynamics in tropical estuaries are controlled by a combination of processes including river discharge, morphology, salinity, erosion and deposition processes, the settling of mud, physico-chemical processes and mangrove swamps. Here we present a consistent set of data aimed at characterising the estuary and thus,

S. Capo; A. Sottolichio; I. Brenon; P. Castaing; L. Ferry

2006-01-01

329

Tobias Nipkow Lawrence C. Paulson Markus Wenzel  

E-print Network

Tobias Nipkow Lawrence C. Paulson Markus Wenzel =Isabelle HOL A Proof Assistant for Higher of a security protocol. The typesetting relies on Wenzel's theory presentation tools. An anno- tated source file

Cengarle, María Victoria

330

Nutrient cycling and foodwebs in Dutch estuaries  

Microsoft Academic Search

In this review several aspects of the functioning of the Dutch estuaries (Ems-Dollard, Wadden Sea, Oosterschelde, Westerschelde,\\u000a Grevelingen and Veerse Meer) have been compared. A number of large European rivers (especially Rhine) have a prevailing influence\\u000a on the nutrient cycling of most Dutch estuaries. Owing to the increased loading of the estuaries with nitrogen and phosphorus\\u000a compounds, effects of eutrophication

P. H. Nienhuis

1993-01-01

331

Morphodynamic equilibrium of alluvial estuaries  

NASA Astrophysics Data System (ADS)

The evolution of the longitudinal bed profile of an estuary, with given plan-form configuration, subject to given tidal forcing at the mouth and prescribed values of water and sediment supply from the river is investigated numerically. Our main goal is to ascertain whether, starting from some initial condition, the bed evolution tends to reach a unique equilibrium configuration asymptotically in time. Also, we investigate the morphological response of an alluvial estuary to changes in the tidal range and hydrologic forcing (flow and sediment supply). Finally, the solution helps characterizing the transition between the fluvially dominated region and the tidally dominated region of the estuary. All these issues play an important role also in interpreting how the facies changes along the estuary, thus helping to make correct paleo-environmental and sequence-stratigraphic interpretations of sedimentary successions (Dalrymple and Choi, 2007). Results show that the model is able to describe a wide class of settings ranging from tidally dominated estuaries to fluvially dominated estuaries. In the latter case, the solution is found to compare satisfactory with the analytical asymptotic solution recently derived by Seminara et al. (2012), under the hypothesis of fairly 'small' tidal oscillations. Simulations indicate that the system always moves toward an equilibrium configuration in which the net sediment flux in a tidal cycle is constant throughout the estuary and equal to the constant sediment flux discharged from the river. For constant width, the bed equilibrium profile of the estuarine channel is characterized by two distinct regions: a steeper reach seaward, dominated by the tide, and a less steep upstream reach, dominated by the river and characterized by the undisturbed bed slope. Although the latter reach, at equilibrium, is not directly affected by the tidal wave, however starting from an initial uniform stream with the constant 'fluvial' slope, the final equilibrium state is reached through an erosional wave, which leads to bed degradation of the upstream 'fluvial reach'. For a given river discharge, the length of the tidal reach increases quite rapidly with tidal amplitude, up to some threshold value of the tidal amplitude above which the length of the estuary becomes comparable with the length of the tidal wave. When the channel plan-form is convergent, deposition of sediments of fluvial origin in the funnel-shaped region drastically changes the equilibrium configuration. The effect of an increasing channel convergence is thus to induce bed aggradation close to the inlet. Nevertheless, tidal forcing only slightly changes the non-tidal profile. The effect of increasing tidal oscillations again leads to an increase of the bed slope at the inlet and to a general bed degradation upstream. The effects of varying sediment supply, flow discharge and river width in the upstream reach have also been investigated and play an important role. Further geomorphological implications of these results will be discussed at the meeting. References Dalrymple, R. W., and K. Choi (2007), Morphologic and facies trends through the fluvialmarine transition in tide-dominated depositional systems: A schematic framework for environmental and sequence-stratigraphic interpretation, Earth-Science Reviews, 81(3-4), 135-174, doi:10.1016/j.earscirev.2006.10.002. Seminara, G., M. Bolla Pittaluga, and N. Tambroni (2012), Morphodynamic equilibrium of tidal channels, Environmental Fluid Mechanics: Memorial Volume in Honour of Prof. Gerhard H. Jirka, 153-174

Tambroni, Nicoletta; Bolla Pittaluga, Michele; Canestrelli, Alberto; Lanzoni, Stefano; Seminara, Giovanni

2014-05-01

332

Ernest Orlando Lawrence Berkeley National Laboratory 03/8/2001 E.O. Lawrence Berkeley National Laboratory  

E-print Network

0 Ernest Orlando Lawrence Berkeley National Laboratory 03/8/2001 E.O. Lawrence Berkeley National Year 2000 Site Name: Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) Operation Office The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) is a multi- program national

333

Ernest Orlando Lawrence Berkeley National Laboratory 06/12/2000 E.O. Lawrence Berkeley National Laboratory  

E-print Network

0 Ernest Orlando Lawrence Berkeley National Laboratory 06/12/2000 E.O. Lawrence Berkeley National Year 1999 Site Name: Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) Operation Office The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) is a multi- program national

334

A theoretical framework for analyzing the effect of external change on tidal dynamics in estuaries  

NASA Astrophysics Data System (ADS)

The most densely populated areas of the world are usually located in coastal areas near estuaries. As a result, estuaries are often subject to intense human interventions, such as dredging for navigation, dam construction and fresh water withdrawal etc., which in some areas has led to serious deterioration of invaluable ecosystems. Hence it is important to understand the influence of such interventions on tidal dynamics in these areas. In this study, we present one consistent theoretical framework for tidal hydrodynamics, which can be used as a rapid assessment technique that assist policy maker and managers to make considered decisions for the protection and management of estuarine environment when assessing the effect of human interventions in estuaries. Analytical solutions to the one-dimensional St. Venant equations for the tidal hydrodynamics in convergent unbounded estuaries with negligible river discharge can be cast in the form of a set of four implicit dimensionless equations for phase lag, velocity amplitude, damping, and wave celerity, as a function of two localized parameters describing friction and convergence. This method allows for the comparison of the different analytical approaches by rewriting the different solutions in the same format. In this study, classical and more recent formulations are compared, showing the differences and similarities associated to their specific simplifications. The envelope method, which is based on the consideration of the dynamics at high water and low water, can be used to derive damping equations that use different friction approximations. This results in as many analytical solutions, and thereby allows one to build a consistent theoretical framework. Analysis of the asymptotic behaviour of the equations shows that an equilibrium tidal amplitude exits reflecting the balance between friction and channel convergence. The framework is subsequently extended to take into account the effect of river discharge. Hence, the analytical solutions are applicable even in the upstream part of an estuary, where the influence of river discharge is remarkable. The proposed analytical solutions are transparent and practical, allowing a quantitative and qualitative assessment of human interventions (e.g., dredging, flow reduction) on tidal dynamics. Moreover, they are rapid assessment techniques that enable the users to set up a simple model and to understand the functioning of the system with a minimum of information required. The analytical model is illustrated in three large-scale estuaries with significant influence by human activities, i.e., the Scheldt estuary in the Netherlands, the Modaomen and the Yangtze estuaries in China. In these estuaries, the correspondence with observations is good, which suggests that the proposed model is a useful, yet realistic and reliable instrument for quick detection of the effect of human interventions on tidal dynamics and subsequent environmental issues, such as salt intrusion.

CAI, H.; Savenije, H.; Toffolon, M.

2013-12-01

335

NEW HAMPSHIRE'S ESTUARIES, THE STATE OF  

EPA Science Inventory

The State of the New Hampshire Estuary Report describes the region's valuable natural resources, explains how natural resources are linked to the cultural and economic well being of New Hampshire, and identifies threats to these resources. This State of the Estuaries Report summa...

336

Estuaries: Where Rivers Meet the Sea  

NSDL National Science Digital Library

This website is the educational site for NOAA's National Estuarine Research Reserve System (NERRS), managed and maintained by NERRS education staff. This site provides, primarily, an avenue for elementary, middle and high school students, and their teachers, to learn more about estuaries, research, and explore NOAAâs âliving laboratoriesâ - the National Estuarine Research Reserves. The Estuary Video Gallery offers a collection of short video clips. The main content themes include relationships between estuaries and humans, life in an estuary, impacts of society upon estuaries and current research and equipment used in monitoring estuaries in video format. Also included are E-Live Backpacks designed to extend and enhance specific Estuaries 101 High-School Curriculum activities by using video clips from our Video Gallery, and relating them to important estuary principles and concepts. Students are asked to review the materials in the E-Live Backpacks, to construct their own compelling questions, actively research those questions, and share their learning through final products. By going through these steps, you will lead students through a project-based learning experience. this site is also available in Spanish.

337

NAME: St. Lucie River Oyster Reef Habitat Restoration Project LOCATION: St. Lucie Estuary, Martin County, Florida  

E-print Network

in the face of sea level rise and climate change by stabilizing shoreline sediments, increasing the spatial County, Florida ACRES: 2 acres oyster reef NON-FEDERAL SPONSOR: Martin County Board of County

US Army Corps of Engineers

338

The Propagation of Tides up Rivers With Special Considerations on the Upper Saint Lawrence River  

NASA Astrophysics Data System (ADS)

The hydrodynamics of rivers affected by tides is dominated by the damping and the distortion induced by quadratic bottom friction. A compact and accurate approximation to the deceleration term, standing for the frictional effect, allows the retention of the concept of harmonics and separation of the time and space variations. It then becomes possible to explain, in terms of basic physics, the transformation of the tide from the estuary, to the zone where it becomes extinct. The theoretical reasoning is supported by pertinent observations collected in the Saint Lawrence river; numerical relations are derived to demonstrate the existence of non-linear effects and to quantitatively link various relevant physical parameters. This analysis, in turn, helps outline approaches to improve the tide predictions in such rivers which happen to have such great economic and strategic importance.

Godin, G.

1999-03-01

339

BBC News Special Report: The Lawrence Inquiry  

NSDL National Science Digital Library

In 1993, 18-year-old Stephen Lawrence was stabbed to death in London in a racially motivated attack. Lawrence's killers have not been successfully prosecuted, and, as this report released by the UK Home Office on February 24 reveals, the London police inquiry into the crime displayed "professional incompetence and institutional racism." Undoubtedly the most infamous racial murder in recent British history, Lawrence's death, the police investigation, and the far-reaching government inquiry which followed are being regarded as a milestone in British race relations, inspiring new private and government initiatives to improve relations as well as proposals for extensive changes in the UK policing and judicial systems. This BBC special report on the Inquiry offers an interactive chronology of events, profiles of key figures, analysis and reaction, archived articles, and the latest news.

340

Health of white sucker within the St. Louis River area of concern associated with habitat usage as assessed using stable isotopes  

EPA Science Inventory

In Spring 2011, 200 adult white sucker were collected in four areas of the St. Louis River Area of Concern (AOC), located in Minnesota and Wisconsin, USA. The areas included the upper AOC as a reference area, the upper estuary, St. Louis Bay and Superior Bay. Grossly visible abno...

341

Numerical modelling of morphodynamics—Vilaine Estuary  

NASA Astrophysics Data System (ADS)

The main objective of this paper is to develop a method to simulate long-term morphodynamics of estuaries dominated by fine sediments, which are subject to both tidal flow and meteorologically induced variations in freshwater run-off and wave conditions. The method is tested on the Vilaine Estuary located in South Brittany, France. The estuary is subject to a meso-macrotidal regime. The semi-diurnal tidal range varies from around 2.5 to 5 m at neap and spring, respectively. The freshwater input is controlled by a dam located approximately 8 km from the mouth of the estuary. Sediments are characterised as mostly fines, but more sandy areas are also found. The morphology of the estuary is highly influenced by the dam. It is very dynamic and changes in a complicated manner with the run-off from the dam, the tide and the wave forcing at the mouth of the estuary. Extensive hydrodynamic and sediment field data have been collected in the past and provide a solid scientific basis for studying the estuary. Based on a conceptual understanding of the morphodynamics, a numerical morphological model with coupled hydrodynamic, surface wave and sediment transport models is formulated. The numerical models are calibrated to reproduce sediment concentrations, tidal flat altimetry and overall sediment fluxes. Scaling factors are applied to a reference year to form quasi-realistic hydrodynamic forcing and river run-off, which allow for the simulations to be extended to other years. The simulation results are compared with observed bathymetric changes in the estuary during the period 1998-2005. The models and scaling factors are applied to predict the morphological development over a time scale of up to 10 years. The influence of the initial conditions and the sequence of external hydrodynamic forcing, with respect to the morphodynamic response of the estuary, are discussed.

Vested, Hans Jacob; Tessier, Caroline; Christensen, Bo Brahtz; Goubert, Evelyne

2013-04-01

342

Mercury sources and transformations in a man-perturbed tidal estuary: The Sinnamary Estuary, French Guiana  

Microsoft Academic Search

The distribution, partition and speciation of mercury (Hg) were studied along the redox gradient of an anthropogenically perturbed tropical estuary, the Sinnamary Estuary in French Guiana. This system is a partially mixed estuary characterized by an anoxic freshwater end-member, while the marine end-member consists of the Amazon Plume.The set up of an artificial oxygenation system in the anoxic freshwater end-member

B. Muresan; D. Cossa; M. Coquery; S. Richard

2008-01-01

343

LAWRENCE S. MOSS Department of Mathematics  

E-print Network

LAWRENCE S. MOSS Department of Mathematics Indiana University Bloomington, Indiana 47405 lsm children. Education 1984: Ph.D., Mathematics, UCLA Ph.D. Dissertation: Power Set Recursion Thesis Advisor: Yiannis N. Moschovakis 1981: M.A., Mathematics, UCLA 1979: B.A., Mathematics, UCLA Academic Employment

Indiana University

344

Struggle for the Soul: John Lawrence Childs  

ERIC Educational Resources Information Center

John Lawrence Childs was born in Eau Claire, Wisconsin on January 11, 1889, the second child of John Nelson Childs and Helen Janette (Nettie) Smith. In childhood Childs absorbed the values of industry, democracy, and a traditional, but socially conscious, religion. Childs was a Methodist and an intensely private person not given to talking about…

Stallones, Jared

2010-01-01

345

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

was specifically designed for testing heating, ventilation, and air conditioning systems. The laboratory testsLBNL 53606 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Improving Air Handler Efficiency in Residential HVAC Applications I.S. Walker, M.D. Mingee and D.E. Brenner Environmental Energy Technologies

346

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

specifically designed for testing heating, ventilation, and air conditioning systems. The laboratory testsLBNL 54760 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Improving Air Handler Efficiency in Houses I.S. Walker Environmental Energy Technologies Division May 2004 This work was supported

347

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

i LBNL-2829E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY The Impact of Wind Power Projects Berkeley National Laboratory is an equal opportunity employer. #12;ii LBNL-2829E The Impact of Wind Power in the U.S. and abroad, and with an increasing number of communities considering wind power development

Lee, Jason R.

348

Lawrence Berkeley National Laboratory University of California  

E-print Network

Lawrence Berkeley National Laboratory University of California Internal Audit T.L. HAMILTON Associate Laboratory Director Computational Research D.L. BROWN Division Director National Energy Research Department Head Operations G.D. KUBIAK Associate Laboratory Director and C.O.O. Environment/Health/ Safety J

Eisen, Michael

349

Radiological Work Authorization Lawrence Berkeley National Laboratory  

E-print Network

Radiological Work Authorization Lawrence Berkeley National Laboratory Environment, Health and is not authorized by this Radiological Work Authorization (RWA). If work in fields greater than 100 mrem/h at 30 cm is necessary, a separate Radiological Work Permit (RWP) is required. Experiment Description (cont

Knowles, David William

350

Storm Water Pollution Prevention Plan Lawrence Berkeley National Laboratory  

E-print Network

Storm Water Pollution Prevention Plan For: Lawrence Berkeley National Laboratory Computation;Storm Water Pollution Prevention Plan (SWPPP) LBNL CRTF UC Project No.912314 LAWRENCE BERKELEY NATIONAL ........................................................ 10 2.6 Identifying of Non-Storm Water Discharges

351

Understanding unemployment and local hiring in Lawrence, Massachusetts : a report for the City of Lawrence  

E-print Network

The purpose of this project is to assess the state of employment in Lawrence, Massachusetts in an effort to understand why the city has consistently struggled with an unemployment rate that is double the state average. ...

Bakhteiarov, Polina

2011-01-01

352

Nitrogen, Phosphorus, and Suspended Solids Concentrations in Tributaries to the Great Bay Estuary Watershed in 2011.  

National Technical Information Service (NTIS)

Nitrogen, phosphorus, and sediment loads to the Great Bay Estuary are a growing concern. The Piscataqua Region Estuaries Partnership (PREP) calculates the nitrogen load from tributaries to the Great Bay Estuary for its State of the Estuaries reports. Ther...

M. A. Wood, P. Trowbridge

2012-01-01

353

Assessing the susceptibility of two UK estuaries to nutrient enrichment  

NASA Astrophysics Data System (ADS)

The susceptibility of two UK estuaries, the Severn and Solva Estuaries to the risks and impacts of nutrient enrichment was investigated in this study by examining nutrients, dissolved oxygen (DO) and turbidity concentrations in the estuaries and applying a risk assessment model based on the UK's Comprehensive Studies Task Team (CSTT) modelling approach. Both estuaries were found to be nutrient enriched. However, there was no evidence of oxygen depletion in the Severn and algal blooms were not observed due to high turbidity, strong tidal currents and tidally induced vertical mixing conditions in the estuary. Although algal blooms were observed in the Solva Estuary, the estuary was well-oxygenated due to the relatively high water exchange rate and consistent rapid flushing in the estuary. The conditions in the Solva Estuary were predicted to be favourable for phytoplankton productivity and the wider potential implications for future water quality protection strategies in the Solva were discussed.

Kadiri, Margaret; Bockelmann-Evans, Bettina; Rauen, William B.

2014-10-01

354

Plankton dynamics along a 180 km reach of the Saint Lawrence River from its headwaters in Lake Ontario  

Microsoft Academic Search

We test the hypothesis that phytoplankton biomass decrease upon entry into the St. Lawrence River from headwaters in Lake\\u000a Ontario is attributable to a range of causal factors including, decreased photosynthetic fitness due to turbulence, cell loss\\u000a due to increased flocculation and subsequent sedimentation, decreases in nutrients, and loss due to grazing. In order to test\\u000a this, changes in phytoplankton

Michael R. Twiss; Carmen Ulrich; Stefanie A. Kring; Jessica Harold; Matthew R. Williams

2010-01-01

355

Lawrence Berkeley National Laboratory EH&S Orientation for  

E-print Network

Lawrence Berkeley National Laboratory EH&S Orientation for Non-Construction Subcontractors, Vendors, and safety (EH&S) requirements at Lawrence Berkeley National Laboratory (LBNL) for subcontractors, vendors-construction subcontractors, vendors, and guests who plan to work at Lawrence Berkeley National Laboratory are required

Knowles, David William

356

From Berkeley Lab to the Marketplace Lawrence Berkeley National Laboratory  

E-print Network

From Berkeley Lab to the Marketplace Smart Lawrence Berkeley National Laboratory Technology Transfer with Partner #12;Lawrence Berkeley National Laboratory Technology Transfer at Berkeley Lab Partnering with Lawrence Berkeley National Laboratory, also known as Berkeley Lab, is located in the hills

Eisen, Michael

357

Copper speciation in estuaries and coastal waters  

E-print Network

The goals of this dissertation are to better understand the sources and the Cu binding ability of ligands that control Cu toxicity in estuaries and harbors, where elevated Cu concentrations have caused documented toxic ...

Kogut, Megan Brook, 1972-

2002-01-01

358

EPA'S BENTHIC HABITAT DATA FOR YAQUINA ESTUARY  

EPA Science Inventory

Scientists at EPA's National Health and Environmental Effects Research Laboratory, Western Ecology Division (WED) have been studying seafloor (benthic) habitats in Yaquina estuary for several years. Those studies were conducted as parts of several research projects, including: e...

359

Environmental Effects of Hydraulic Dredging in Estuaries.  

National Technical Information Service (NTIS)

Hydraulic channel and shell dredging and open water spoil disposal have little significant immediate effect on water quality in Alabama estuaries. Almost all of the sediment discharged by dredges settles very rapidly and is transported by gravity along th...

E. B. May

1973-01-01

360

Water renewal timescales in the Scheldt Estuary  

NASA Astrophysics Data System (ADS)

Using the concepts of the Constituent-oriented Age and Residence time Theory (CART), we compute timescales related to the water renewal in the Scheldt Estuary (The Netherlands/Belgium). Three different timescales are used to better understand and characterize the dynamics of the estuary: the age of the renewing water, the residence time and the exposure time. The residence time is the time taken by a water parcel to leave the estuary for the first time while the exposure time is the total time spent by a water parcel in the estuary including re-entries. The age of a renewing water parcel is defined as the time elapsed since it entered the estuary. The renewing water was split into three types: the water originating from the sea, the water originating from the upstream fresh tidal rivers and the water originating from the different canals and docks connected to the estuary. Every timescale is computed at any time and position by means of the finite-element, unstructured-mesh model SLIM. This results in movies of the timescale fields (shown as Supplementary material), allowing a detailed analysis of their spatial and temporal variabilities. The effect of the M2 tide and the discharge regime (winter, summer or average situation) on the timescales is also investigated. Tidally-averaged timescales vary little over the width of the estuary and hence exhibit a virtually one-dimensional behaviour. However, around these average values, the timescales can vary hugely over a tidal cycle, with amplitudes that significantly depend on the space coordinates. The reason thereof has yet to be elucidated. These results underscore the need for two- or three-dimensional models with high temporal resolution for investigating the dynamics of the Scheldt Estuary.

de Brye, Benjamin; de Brauwere, Anouk; Gourgue, Olivier; Delhez, Eric J. M.; Deleersnijder, Eric

2012-06-01

361

Iodine speciation in the Nile River estuary  

Microsoft Academic Search

During high- and low-flood periods, surface and bottom water samples were collected along the Nile River estuary for the voltammetric determination of dissolved iodine species. Iodine occurs in the estuary as iodate, iodide and organic iodine. Total iodine increases with salinity, showing a source feature in surface and bottom waters during high-flow indicating iodine input. During low-flow, total iodine showed

M. A. R Abdel-Moati

1999-01-01

362

Estuaries.  

ERIC Educational Resources Information Center

This publication is designed for use in standard science curricula to develop oceanologic manifestations of certain science topics. Included are teacher guides, student activities, and demonstrations designed to impart ocean understanding to high school students. When the student has completed this unit, he should be able to: (1) define an…

Awkerman, Gary L.

363

Lawrence Livermore National Laboratory Summer Employment Summary  

SciTech Connect

This document will serve as a summary of my work activities as a summer employee for the Lawrence Livermore National Laboratory (LLNL). The intent of this document is to provide an overview of the National Ignition Facility (NIF) project, to explain the role of the department that I am working for, and to discuss my specific assigned tasks and their impact on the NIF project as a whole.

Wilson, A J

2002-08-06

364

The geothermal program at Lawrence Berkeley Laboratory  

SciTech Connect

The main purpose of the geothermal program at Lawrence Berkeley Laboratory is to develop, improve and validate methods and instrumentation to: (1) determine geothermal reservoir parameters; (2) detect and characterize reservoir fractures and boundaries; and (3) identify and evaluate the importance of reservoir processes. The ultimate objective of the program, which includes field, theoretical and modeling activities, is to advance the state-of-the-art for characterizing geothermal systems and evaluating their productive capacity and longevity under commercial exploitation.

Lippmann, M.J.

1987-06-01

365

Life History and Population Characteristics of Striped Bass in Atlantic Canada  

Microsoft Academic Search

Populations of striped bass Morone saxatilis occur in three regions of Atlantic Canada: the St. Lawrence River and estuary in Quebec; the Gulf of St. Lawrence from Chaleur Bay through Northumberland Strait; and rivers in New Brunswick and Nova Scotia draining into the Bay of Fundy. At least nine rivers are known or believed to sustain spawning populations: the St.

Roger A. Rulifson; Michael J. Dadswell

1995-01-01

366

MOBILE BAY NATIONAL ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

In simplest terms, an estuary is defined as an area where rivers meet the sea. They are transitional zones where freshwater rivers meet tidally influenced marine waters. Estuaries are considered environmentally and economically important because of their exceptional biological di...

367

SAN FRANCISCO ESTUARY PROJECT COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

The Estuary, a significant natural resource, San Francisco Bay and the Delta combine to form the West Coast's largest estuary. The Estuary conveys the waters of the Sacramento and San Joaquin Rivers to the Pacific Ocean. It encompasses roughly 1,600 square miles, drains over 40 p...

368

THE ATLANTIC STURGEON, ACIPENSER OXYRHYNCHUS, IN THE DELAWARE RIVER ESTUARY  

E-print Network

summer. This seasonal distribution appeared similar to that described for the Hudson River estuaryTHE ATLANTIC STURGEON, ACIPENSER OXYRHYNCHUS, IN THE DELAWARE RIVER ESTUARY HAROLD M. BRUNDAGE III River estuary from 1958 through 1980 were obtained from the literature, unpublished data, and logs

369

Seasonal variation of sediment deposition in the Hudson River estuary  

Microsoft Academic Search

During and following the spring freshet, rapid rates of sediment deposition were observed in the Hudson River estuary. Side-scan sonar surveys and sediment coring studies revealed a large amount of spatial variability in sedimentation within the estuary and a distinct seasonal progression. During the freshet, sediment was deposited in the seaward reaches of the estuary. In the two-month period after

Jonathan D Woodruff; W. Rockwell Geyer; Christopher K Sommerfield; Neal W Driscoll

2001-01-01

370

Monitoring and Managing Contamination in the San Francisco Estuary 199399  

E-print Network

on Estuary management contributed by the staff of the San Francisco Bay Regional Water Quality Control Board (Regional Board). BAY VS. ESTUARY Although most people still refer to the expanse of water inside the Golden indicate that the San Francisco Estuary is moderately contami- nated. Although levels of many contaminants

371

The Estuary Guide. Level 3: High School. Draft.  

ERIC Educational Resources Information Center

Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the high school level seeks to teach what estuaries are; provide opportunities to practice decision-making that affects estuaries; and encourage students to…

Alexander, Glen; And Others

372

Lawrence and His Laboratory: A Historian's View of the Lawrence Years  

NSDL National Science Digital Library

Lawrence Berkeley Laboratory celebrated its 65th anniversary, and created this web site as a tribute to its founder. Ernest Orlando Lawrence, who invented the cyclotron, opened the way to "a Golden Age of particle physics and revolutionary discoveries about the nature of the universe." The story was originally told by the lab's public information department in 1981. All in all, this site provides a personal look into one of the foremost physics labs in the world, at a time when its discoveries were literally shaking the world.

Heilbron, J. L.; Seidel, Robert W.; Wheaton, Bruce R.

1981-01-01

373

Proceedings of the 6th Annual Meeting for Excess Weapons Plutonium Disposition: Plutonium Packaging, Storage and Transportation and Waste Treatment, Storage and Disposal Activities. Held in St. Petersburg, Russia on November 15-17, 2004.  

National Technical Information Service (NTIS)

The sixth annual Excess Weapons Plutonium Disposition meeting organized by Lawrence Livermore National Laboratory (LLNL) was held November 15-17, 2004, at the State Education Center (SEC), 4 Aerodromnya Drive, St. Petersburg, Russia. The meeting discussed...

L. J. Jardine

2004-01-01

374

Seasonal dissolved inorganic nitrogen and phosphorus budgets for two sub-tropical estuaries in south Florida, USA  

NASA Astrophysics Data System (ADS)

Interactions among geomorphology, circulation, and biogeochemical cycling determine estuary responses to external nutrient loading. In order to better manage watershed nutrient inputs, the goal of this study was to develop seasonal dissolved inorganic nitrogen (DIN) and phosphorus (DIP) budgets for the two estuaries in south Florida, the Caloosahatchee River estuary (CRE) and the St. Lucie Estuary (SLE), from 2002 to 2008. The Land-Ocean Interactions in the Coastal Zone (LOICZ) approach was used to generate water, salt, and DIN and DIP budgets. Results suggested that internal DIN production increases with increased DIN loading to the CRE in the wet season. There were hydrodynamic effects as water column concentrations and ecosystem nutrient processing stabilized in both estuaries as flushing time increased to >10 d. The CRE demonstrated heterotrophy (net ecosystem metabolism or NEM < 0.0) across all wet and dry season budgets. While the SLE was sensitive to DIN loading, system autotrophy (NEM > 0.0) increased significantly with external DIP loading. This included DIP consumption and a bloom of a cyanobacterium (Microcystis aeruginosa) following hurricane-induced discharge to the SLE in 2005. Additionally, while denitrification provided a microbially-mediated N loss pathway for the CRE, this potential was not evident for the SLE where N2 fixation was favored. Disparities between total and inorganic loading ratios suggested that the role of dissolved organic nitrogen (DON) should be assessed for both estuaries. Nutrient budgets indicated that net internal production or consumption of DIN and DIP fluctuated with inter- and intra-annual variations in freshwater inflow, hydrodynamic flushing, and primary production. The results of this study should be included in watershed management plans in order to maintain favorable conditions of external loading relative to internal material cycling in both dry and wet seasons.

Buzzelli, C.; Wan, Y.; Doering, P. H.; Boyer, J. N.

2013-10-01

375

A Bioenergetics Modeling Evaluation of Top-down Control of Ruffe in the St. Louis River, Western Lake Superior  

Microsoft Academic Search

Ruffe (Gymnocephalus cernuus), were accidentally introduced into the St. Louis River estuary, western Lake Superior, in the mid 1980s and it was feared that they might affect native fish through predation on eggs and competition for forage and habitat. In an effort to control the abundance of ruffe and limit dispersal, a top-down control strategy using predators was implemented in

Kathleen R. Mayo; James H. Selgeby; Michael E. McDonald

1998-01-01

376

Nutrient transports in a Swedish estuary  

NASA Astrophysics Data System (ADS)

Himmerfjärd is a Swedish estuary bordering on the Baltic. The estuary lacks astronomical tides and its circulation is driven by winds and freshwater runoff. Because of a tertiary sewage treatment plant located at its inner end, the estuary is becoming increasingly eutrophic. A field study was carried out for a 78-day period in late summer and early fall of 1977 to determine rates of nutrient transport and to construct nutrient budgets. Since physical parameters (current velocity, temperature, salinity, winds and water level changes) were measured more frequently than nutrients (phosphate, nitrate, nitrite and ammonium) it was necessary to develop a suitable method to calculate nutrient flux time series and net nutrient fluxes. Over the study period, Himmerfjärd imported phosphorus and exported nitrogen. Direction of nutrient fluxes and changes in flux direction were consistent with the structure of the baroclinic currents.

Wilmot, Wayne; Toll, Peter; Kjerfve, Björn

1985-08-01

377

Stratigraphic Evidence of Eutrophication in an Estuary  

NASA Astrophysics Data System (ADS)

Vertical changes in chlorophyll degradation products preserved in sediments deposited in an urban estuary show a significant increase in algal productivity with the introduction of sewage effluent into the river. By comparison, algal production during intensive agriculture of the watershed, including heavy applications of fertilizers, was less by an order of magnitude where there was no sewage discharge from a point source. Concentrations of orthophosphorus correspond with concentrations of algal cells and chlorophyll in the water column and are greater by an order of magnitude where sewage is discharged into an estuary draining an urban-agricultural watershed than where there is no sewage. The response of the estuary to short- and long-term changes in the amount of sewage discharged is reflected by similar changes in chlorophyll production. However, chlorophyll production does not correspond with increases in the amount of fertilizers used in recent years over the amount used in the middle to late nineteenth century.

Brush, Grace S.

1984-05-01

378

Teaching Ocean Sciences in the 21st Century Classroom: Lab to Classroom Videoconferencing  

Microsoft Academic Search

Teaching Ocean Science in the 21st Century Classroom (TOST) is a Center for Ocean Sciences Education Excellence (COSEE CA) initiative aimed at developing and disseminating technology-based instructional strategies, tools and ocean science resources for both formal and informal science education. San Diego Unified School District (SDUSD), Scripps Institution of Oceanography (SIO) and the Lawrence Hall of Science (LHS) have established

C. L. Peach; W. Gerwick; L. Gerwick; M. Senise; C. S. Jones; K. Malloy; A. Jones; E. Trentacoste; J. Nunnery; T. Mendibles; D. Tayco; L. Justice; R. Deutscher

2010-01-01

379

Research News at Lawrence Berkeley Laboratory  

NSDL National Science Digital Library

From the Lawrence Berkeley Laboratory's (LBL) Public Information Department, the Research News Website contains a store of news on physics, chemistry, and life science research. Written in a layperson's language, this resource accesses current news releases and the lab's newspaper (Currents) and magazine (Research Review). The highlight of this site is the searchable Science Articles Archive which holds over 900 articles from the above-mentioned news sources. The archives include sections on Accelerator and Fusion Research, Chemical Sciences, General Physics, and X-ray Research, among many others. A "News Release Delivery Service" emails the latest LBL news to subscribers.

380

Lawrence Berkeley Laboratory 1994 site environmental report  

SciTech Connect

The 1994 Site Environmental Report summarizes environmental activities at Lawrence Berkeley Laboratory (LBL) for the calendar year (CY) 1994. The report strives to present environmental data in a manner that characterizes the performance and compliance status of the Laboratory`s environmental management programs when measured against regulatory standards and DOE requirements. The report also discusses significant highlight and planning efforts of these programs. The format and content of the report are consistent with the requirements of the U.S. Department of Energy (DOE) Order 5400.1, General Environmental Protection Program.

NONE

1995-05-01

381

Modeling tidal distortion in the Ogeechee Estuary  

NASA Astrophysics Data System (ADS)

A 3D numerical model is used to simulate the distortion of tidal hydrodynamics in the Ogeechee Estuary, GA. The Ogeechee, like many estuaries found in the Southeastern US, consists of shallow channel networks and extensive intertidal storage in the form of wetlands. Such features are known to induce non-linear overtide generation and significant tidal distortion, otherwise known as tidal stage asymmetry. Simulations are run with varying parameters to assess their effects on modeling tidal distortion for the Ogeechee Estuary: bottom friction coefficients, enhanced wetland friction coefficients, and tidal flat elevations. To succinctly quantify the degree of distortion across the domain, the statistical parameters of skewness and asymmetry are calculated for time series of water surface heights and channel volume fluxes. The intertidal storage causes the peak flood flux to occur later and the peak ebb flux to occur earlier, thereby resulting in positive asymmetry for the volume flux for the full estuary. However, ebb dominance is a localized feature and varies throughout the estuary. Increasing the intertidal storage by lowering wetland elevation enhances the effects on high tide and volume flux magnitudes, decreasing the ebb-dominance and volume flux asymmetry typically associated with intertidal storage thereby indicating the importance of the wetland elevation over the total storage volume. Increased channel bottom friction reduces ebb-dominance by extending the duration of the falling tide. More interestingly, increased wetland friction reduces the influence of wetland intertidal storage on tidal distortion. The model suggests an increase in wetland friction does little to dampen wave propagation at high tide but rather impedes the lateral flooding of wetlands, reducing ebb dominance. Tidal flat elevation has the largest impact on distortion for the Ogeechee Estuary whereas enhanced wetland and bottom frictional influences on distortion are small, albeit not insignificant.

Bruder, Brittany; Bomminayuni, Sandeep; Haas, Kevin; Stoesser, Thorsten

2014-10-01

382

Ciliated Protozoa of the polluted Tees estuary  

NASA Astrophysics Data System (ADS)

In a study of the ciliated Protozoa of Bran Sand, a sheltered beach in the Tees estuary, 20 putative species were identified. This beach was richer in species than the nearby North Gare beach. In experimental batch cultures, seawater from the estuary had an inhibitory effect upon growth of a strain of Uronema marinum Dujardin which was isolated from an unpolluted beach at Robin Hood's Bay. The tolerance to metals of a Tees strain of U. marinum was assessed in simple toxicity tests; lethal levels for this strain were found to be similar to those reported elsewhere for the Robin Hood's Bay strain.

Parker, James G.

1981-03-01

383

San Francisco Estuary: Invasive Spartina Project  

NSDL National Science Digital Library

The Invasive Spartina Project was developed by the California State Coastal Conservancy to determine the extent and address the problem of invasive Spartina in the San Francisco Estuary. This Web site describes the efforts of the Invasive Spartina Project and the risk that Spartina poses. A variety of maps and photos are used to describe the results of the 2000-2001 survey of Spartina populations within the estuary. A host of other documents regarding Spartina and this project are also available in Adobe Acrobat (.pdf) format.

2002-01-01

384

Lawrence Berkeley Laboratory Institutional Plan FY 1987-1992  

E-print Network

Light Ion Biomedical Research Accelerator Lawrence Livermore National Laboratory Laboratori Nazionali di Frascati Multiple-Beam Experiment Multiprogram Energy Laboratory Facilities Support Magnetic Fusion

Various

1986-01-01

385

BATHYMETRY FOR ALBEMARLE AND PAMLICO ESTUARIES, NC  

EPA Science Inventory

Bathymetry for the Albemarle and Pamlico Estuaries obtained from National Oceanographic and Atmospheric Administration-National Ocean Service (NOAA-NOS). See the metadata within the files from NOAA-NOS for more details and warnings concerning merging with US Geolgoical Survey Dig...

386

Listening to Estuary English in Singapore  

ERIC Educational Resources Information Center

In Singapore, many people are not familiar with Estuary English (EE), the variety of English becoming popular in much of southern England. In the current study, when students listened to interviews with EE speakers and were asked to transcribe orthographically what they heard, most of them had severe problems. Features of pronunciation that…

Deterding, David

2005-01-01

387

INDICATORS OF ECOSYSTEM INTEGRITY FOR ESTUARIES  

EPA Science Inventory

Jordan, Stephen J. and Lisa M. Smith. In press. Indicators of Ecosystem Integrity for Estuaries. In: Proceedings of the Estuarine Indicators Workshop, 29-31 October 2003, Sanibel Island, FL. Sanibel-Captiva Conservation Foundation, Sanibel, FL. 23 p. (ERL,GB 1194). Ideal ...

388

Vegetation of the Elwha River Estuary  

E-print Network

, 2011, chapter 4, this report). Removal of the two dams upstream on the Elwha River, anticipated be compared, following the impending removal of Glines Canyon and Elwha Dams upstream on the Elwha River. DamChapter 8 8 Chapter Vegetation of the Elwha River Estuary By Patrick B. Shafroth, Tracy L. Fuentes

389

San Francisco Estuary Institute 7770 Pardee Road  

E-print Network

San Francisco Estuary Institute 7770 Pardee Road Oakland, CA 94621 (510) 746­7334 www Drawbridge (Courtesy of UCB and UCSB) 1857 Near the mouth of Alameda Creek 1896 Development of modern salt the origin of many of the early Euro-American salt pond complexes. Management for salt production most likely

390

Climate change and its impacts on estuaries  

EPA Science Inventory

Past, present, and future research by WED scientists in the TEP region will be described to lay the foundation for examination of potential climate change effects on estuaries and the broader coastal zone in the Pacific Northwest (PNW). Results from National Coastal Assessments,...

391

Tracing kepone contamination in James estuary sediments  

SciTech Connect

The escape of Kepone into the James River estuary, Virginia, for more than nine years produced widespread contamination of the sediments with important ecological consequences. The pollutant extended seaward more than 100 km from its source and contaminated an estimated 31 million tonnes of sediment to depths of more than 60 cm. Kepone spread through the food chain and to every segment of the environment from marshes to the channel floor. Kepone escaped mainly during high river inflow from a point source in freshwater tributaries. Near the source Kepone is associated with organic material but in the lower estuary it is adsorbed on finegrained sediment. A bulk of the contaminated sediment is transported and trapped by the estuarne circulation. It accumulates in the turbidity maximum of the middle estuary far from the source. In this zone it is deposited in less energetic sites where sedimentation is relatively fast. Contamination extends downward > 60 cm; peak concentrations at 10 to 25 cm relate to high production in 1974. The Kepone inventory is now being buried by less contaminated sediment. Recovery is most rapid in the middle estuary where contamination was most intense.

Nichols, M.M. (Virginia Inst. of Marine Sciences, Gloucester Point); Cutshall, N.H.

1981-01-01

392

Yeast community survey in the Tagus estuary  

Microsoft Academic Search

The yeast community in the waters of the Tagus estuary, Portugal, was followed for over a year in order to assess its dynamics. Yeast occurrence and incidence were measured and this information was related to relevant environmental data. Yeast occurrence did not seem to depend upon tides, but river discharge had a dramatic impact both on the density and diversity

João M. G. C. F. de Almeida

2005-01-01

393

BCG Approaches for Improved Management of Estuaries  

EPA Science Inventory

Estuaries and other complex aquatic systems are exposed to a variety of stressors that act at several scales, but are managed piecemeal - - often resulting in a ?death by 1000 cuts? caused by cumulative impacts to these valued resources. To address this, managers need tools that...

394

MODELING FINE SEDIMENT TRANSPORT IN ESTUARIES  

EPA Science Inventory

A sediment transport model (SEDIMENT IIIA) was developed to assist in predicting the fate of chemical pollutants sorbed to cohesive sediments in rivers and estuaries. Laboratory experiments were conducted to upgrade an existing two-dimensional, depth-averaged, finite element, coh...

395

Estuaries and Tidal Marshes. Habitat Pac.  

ERIC Educational Resources Information Center

This educational packet consists of an overview, three lesson plans, student data sheets, and a poster. The overview examines estuaries and tidal or salt marshes by discussing the plants and animals in these habitats, marsh productivity, benefits and management of the habitats, historical aspects, and development and pollution. A glossary and list…

Fish and Wildlife Service (Dept. of Interior), Washington, DC.

396

Kaua'i: Streams and Estuaries.  

ERIC Educational Resources Information Center

Designed to help teachers develop students' awareness and understanding of some of Hawaii's endangered aquatic resources, this module contains activities and instructional suggestions for use with intermediate as well as high school students. The module is divided into two sections which explore the streams and estuaries of Kauai. Activities in…

Hawkins, John, Ed.; Murakami, Colleen, Ed.

397

75 FR 4822 - Decision To Evaluate a Petition To Designate a Class of Employees for the Lawrence Livermore...  

Federal Register 2010, 2011, 2012, 2013

...for the Lawrence Livermore National Laboratory, Livermore, CA, To Be Included...for the Lawrence Livermore National Laboratory, Livermore, California...Facility: Lawrence Livermore National Laboratory. Location: Livermore,...

2010-01-29

398

October, 2009 Page 1 Lawrence Berkeley National Laboratory  

E-print Network

October, 2009 Page 1 Lawrence Berkeley National Laboratory Guidelines on Laboratory of the Ernest Orlando Lawrence Berkeley National Laboratory, consistent with the DOE guidelines (DOE Order 0 413 of Berkeley Lab and the DOE and which further Berkeley Lab's position as a leading national laboratory

399

A Hydrologic and Geomorphic Model of Estuary Breaching and Closure  

NASA Astrophysics Data System (ADS)

Many coastal estuaries are separated seasonally from the ocean by a swash-deposited beach berm. The opening of the inlet may occur by fluvial erosion of the beach berm and closure occurs when sand deposition outpaces erosion of the inlet. To better understand how the hydrology of estuaries affects breaching and closing patterns, a model is developed that incorporates an estuary hydrologic budget with a geormorphic model of the inlet system. When calibrated, the model is able to reproduce the initial seasonal breaching, seasonal closure, intermittent closures and breaches, and the low-streamflow estuary hydrology of the Carmel Lagoon, located in Central California. For two years when the estuary inlet drains directly across the beach-berm in accordance with model assumptions, the calibrated model predicts the observed 48-hour estuary stage amplitude with correlation coefficients of 0.77 and 0.65. For the calibrated model, streamflow is the predominant control on whether the estuary inlet is open or closed. In a series of sensitivity analyses, it is seen that the function of bar-built, coastal estuaries are sensitive to morphologic and hydrologic variations of the beach berm, and changes to the estuary storage itself. By varying individual components of the berm-system and estuary storage, the amount of the time the estuary is open changes -43 - 28% for the 18.2 model period. The morphology of the berm affects barrier groundwater flow, inlet hydraulics, and estuary storage. Importantly, the elevation of the berm determines the volume of water that must enter the estuary in order to breach, and it modulates the wave-overtopping flux. A high berm renders streamflow the predominant control on function and decreases the amount of time that the estuary is open by 4%, whereas a lower berm allows wave-overtopping to contribute to function and increases time open by 24%. By excavating an estuary, it will breach less frequently (-32% change in open) and store water up to 3 months later into the summer. Beach aquifer hydraulic conductivity significantly alters the amount of time the estuary is open or closed; a high hydraulic conductivity berm remains open 43% less than the calibrated model, but a decreased hydraulic conductivity causes only an 11% increase in time open. As a result of sea level rise of 1.67m by 2100, and a beach berm that remains in its current location and accretes vertically, the amount of time the estuary remains open may decrease up to 22%. Model results indicate that the amount of time the estuary is open is more sensitive to changes in wave run-up than the amount of sand deposited in the inlet per each overtopping wave.

Rich, A.; Keller, E. A.

2012-12-01

400

Geologic map of Saint Lawrence Island, Alaska  

USGS Publications Warehouse

Saint Lawrence Island is located in the northern Bering Sea, 190 km southwest of the tip of the Seward Peninsula, Alaska, and 75 km southeast of the Chukotsk Peninsula, Russia (see index map, map sheet). It lies on a broad, shallow-water continental shelf that extends from western Alaska to northeastern Russia. The island is situated on a northwest-trending structural uplift exposing rocks as old as Paleozoic above sea level. The submerged shelf between the Seward Peninsula and Saint Lawrence Island is covered mainly with Cenozoic deposits (Dundo and Egiazarov, 1982). Northeast of the island, the shelf is underlain by a large structural depression, the Norton Basin, which contains as much as 6.5 km of Cenozoic strata (Grim and McManus, 1970; Fisher and others, 1982). Sparse test-well data indicate that the Cenozoic strata are underlain by Paleozoic and Proterozoic rocks, similar to those exposed on the Seward Peninsula (Turner and others, 1983). Saint Lawrence Island is 160 km long in an east-west direction and from 15 km to 55 km wide in a north-south direction. The east end of the island consists largely of a wave-cut platform, which has been elevated as much as 30 m above sea level. Isolated upland areas composed largely of granitic plutons rise as much as 550 m above the wave-cut platform. The central part of the island is dominated by the Kookooligit Mountains, a large Quaternary shield volcano that extends over an area of 850 km2 and rises to an elevation of 630 m. The west end of the island is composed of the Poovoot Range, a group of barren, rubble-covered hills as high as 450 m that extend from Boxer Bay on the southwest coast to Taphook Mountain on the north coast. The Poovoot Range is flanked on the southeast by the Putgut Plateau, a nearly flat, lake-dotted plain that stands 30?60 m above sea level. The west end of the island is marked by uplands underlain by the Sevuokuk pluton (unit Kg), a long narrow granite body that extends from Gambell on the north to near Boxer Bay on the south. Headlands having rugged cliffs or narrow, boulder-strewn beaches characterize the southwest coastline. The geologic map of Saint Lawrence Island was prepared from published and unpublished field investigations carried out between 1966 and 1971 by W.W. Patton, Jr., Bela Csejtey, Jr., T.P. Miller, J.T. Dutro, Jr., J.M. Hoare, and W.H. Condon (Patton and Csejtey, 1971, 1980) and data from Ormiston and Fehlmann (1969). Fossils collected during these investigations are reported in the Alaska Paleontological Database (www.alaskafossil.org), and mineral resource information is summarized in the online Alaska Resource Data File (Hudson, 1998).

Patton, William W., Jr.; Wilson, Frederic H.; Taylor, Theresa A.

2011-01-01

401

Lawrence Berkeley Laboratory Affirmative Action Program. Revised  

SciTech Connect

The Lawrence Berkeley Laboratory`s Affirmative Action Program (AAP) serves as a working document that describes current policies, practices, and results in the area of affirmative action. It represents the Laboratory`s framework for an affirmative approach to increasing the representation of people of color and women in segments of our work force where they have been underrepresented and taking action to increase the employment of persons with disabilities and special disabled and Vietnam era veterans. The AAP describes the hierarchy of responsibility for Laboratory affirmative action, the mechanisms that exist for full Laboratory participation in the AAP, the policies and procedures governing recruitment at all levels, the Laboratory`s plan for monitoring, reporting, and evaluating affirmative action progress, and a description of special affirmative action programs and plans the Laboratory has used and will use in its efforts to increase the representation and retention of groups historically underrepresented in our work force.

NONE

1995-06-01

402

Developed by: Lawrence Berkeley National Laboratory with input from industry partners representing high tech  

E-print Network

LBNL-50599 Developed by: Lawrence Berkeley National Laboratory with input from industry partners For High Tech Buildings #12;DISCLAIMER The Lawrence Berkeley National Laboratory, 1 Cyclotron Road Energy Technologies Division Ernest Orlando Lawrence Berkeley National Laboratory University

403

Biographical Sketch: Thomas W. Kirchstetter Environmental Energy Technologies Division Lawrence Berkeley National Laboratory  

E-print Network

Research Associate, Lawrence Berkeley National Laboratory, 1998 ­ 2000 (b) Current Appointments Associate Engineering Staff Scientist, Lawrence Berkeley National Laboratory, 2000 ­ present Environmental Energy Lecture Series Committee, Lawrence Berkeley National Laboratory, 2011 (e) Honors Outstanding Mentor Award

404

Lawrence Berkeley National Laboratory Advanced Light Source Beamline 1.4  

E-print Network

Lawrence Berkeley National Laboratory Advanced Light Source ­ Beamline 1.4 Maxime Chevillon 2nd with them. #12;3 Table of Contents LAWRENCE BERKELEY NATIONAL LABORATORY Berkeley National Laboratory Lawrence Berkeley National Laboratory (Berkeley Lab

405

77 FR 15722 - Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Management...  

Federal Register 2010, 2011, 2012, 2013

...Incidental to Specified Activities; Russian River Estuary Management Activities AGENCY...take marine mammals incidental to Russian River estuary management activities. Pursuant...conducted in management of the Russian River estuary in Sonoma County,...

2012-03-16

406

76 FR 8345 - Endangered and Threatened Species; Recovery Plan Module for Columbia River Estuary Salmon and...  

Federal Register 2010, 2011, 2012, 2013

...Species; Recovery Plan Module for Columbia River Estuary Salmon and Steelhead AGENCY: National...availability; recovery plan module for Columbia River estuary salmon and steelhead...announces the adoption of the Columbia River Estuary Endangered Species Act...

2011-02-14

407

78 FR 14985 - Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Management...  

Federal Register 2010, 2011, 2012, 2013

...Incidental to Specified Activities; Russian River Estuary Management Activities AGENCY...take marine mammals incidental to Russian River estuary management activities. Pursuant...conducted in management of the Russian River estuary in Sonoma County,...

2013-03-08

408

Population Structure of an Invasive Parthenogenetic Gastropod in Coastal Lakes and Estuaries of Northern KwaZulu-Natal, South Africa  

PubMed Central

Background Estuaries and coastal lakes receive little attention despite being heavily invaded by non-indigenous invasive species (NIS). In these situations, studies of population dynamics in invaded habitats can provide valuable insights into how NIS interact with new environments. Tarebia granifera is a prosobranch gastropod from south-east Asia which has invaded other sub-tropical parts of the world. This study addresses whether a small number of key environmental factors influences gastropod communities, and specifically how the population density and size structure of T. granifera were influenced by environmental change in estuaries and coastal lakes in southern Africa. Methodology/Principal Findings T. granifera's density, number of brooded juveniles and size structure were measured at the St. Lucia Estuary, Mgobozeleni Estuary, Lake Sibaya and Lake Nhlange. Size structure was classified according to shell height (SH). All dissected individuals were found to be female and free from trematode infection. Salinity, water depth, temperature, and pH were the main factors correlated with population density of gastropod communities. T. granifera often reached densities well over 1000 ind. m?2, displacing indigenous gastropods and becoming a dominant component of the benthic community. T. granifera successfully invaded estuaries despite frequent exposure to high salinity and desiccation, which could together eliminate >97% of the population. The persistence of T. granifera was ensured due to its high fecundity and the environmental tolerance of large adults (20–30 mm SH) which carried an average of 158±12.8 SD brooded juveniles. Repeat introductions were not essential for the success of this parthenogenetic NIS. Conclusion/Significance There is a need for a broader study on the reproductive biology of T. granifera (including the previously overlooked “brood pouch ecology”), which affects population dynamics and may be relevant to other parthenogenetic NIS, such as Melanoides tuberculata and Potamopyrgus antipodarum. PMID:21904629

Miranda, Nelson A. F.; Perissinotto, Renzo; Appleton, Christopher C.

2011-01-01

409

Estuaries. Estuaries are places where fresh and salt water mix. Typically they occur where rivers enter the sea. Estero Limantour, Drakes' Bay, Point Reyes National Seashore.  

E-print Network

Estuaries Lecture 18 #12;Estuaries. Estuaries are places where fresh and salt water mix. Typically than an equivalent volume of fresh water. If you go back to the graph of water density as a function and shallow, and river currents are often strong. Hence salt and fresh water are often mixed in estuaries

Richerson, Peter J.

410

A report published by the San Francisco Estuary Institute and the Regional Monitoring Program for Water Quality in the San Francisco Estuary  

E-print Network

and the Regional Monitoring Program for Water Quality in the San Francisco Estuary The Pulse of the Estuary Monitoring and Managing Water Quality in the San Francisco Estuary 35 Years After the Clean Water Act #12: Monitoring and Managing Water Quality in the San Francisco Estuary. SFEI Contribution 532. San Francisco

411

Cassano G, Bellantuono V, Ardizzone C, and Lippe C (2003) Pyrethroid stimulation of ion transport across frog skin. Environmental  

E-print Network

. (2002) Cancer in wildlife, a case study: Beluga from the St. Lawrence estuary, Quebec, Canada) Overview of studies on liver carcinogenesis in English sole from Puget Sound: Evidence for a xenobiotic

Rajakaruna, Nishanta

412

Water resources data, Ohio: Water year 1991. Volume 2, St. Lawrence River Basin: Statewide project data  

SciTech Connect

The Water Resources Division of the US Geological Survey (USGS), in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Ohio each water year. These data, accumulated during many years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the USGS, the data are published annually in this report series entitled ``Water Resources Data--Ohio.`` This report (in two volumes) includes records on surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 131 streamflow-gaging stations, 95 miscellaneous sites; (2) stage and content records for 5 streams, lakes, and reservoirs; (3) water-quality for 40 streamflow-gaging stations, 378 wells, and 74 partial-record sites; and (4) water levels for 431 observation wells.

Shindel, H.L.; Klingler, J.H.; Mangus, J.P.; Trimble, L.E.

1992-03-01

413

ST. LAWRENCE ISLANDS NATIONAL PARK OF CANADA MALLORYTOWN LANDING, ONTARIOVOL. 1, NO. 2 FALL 2006  

E-print Network

Morin Turtles and snakes and trees, oh my! An update on ecosystem research & why you should care monitor the health of the 1000 Islands ecosystem. From eagles to snakes to wetlands, the latest news on the park year. Why should we care if black rat snakes become extinct? Why should we help the local turtle

Blouin-Demers, Gabriel

414

Marine mammal strandings and environmental changes: a 15-year study in the St. Lawrence ecosystem.  

PubMed

Understanding the effects of climatic variability on marine mammals is challenging due to the complexity of ecological interactions. We used general linear models to analyze a 15-year database documenting marine mammal strandings (1994-2008; n?=?1,193) and nine environmental parameters known to affect marine mammal survival, from regional (sea ice) to continental scales (North Atlantic Oscillation, NAO). Stranding events were more frequent during summer and fall than other seasons, and have increased since 1994. Poor ice conditions observed during the same period may have affected marine mammals either directly, by modulating the availability of habitat for feeding and breeding activities, or indirectly, through changes in water conditions and marine productivity (krill abundance). For most species (75%, n?=?6 species), a low volume of ice was correlated with increasing frequency of stranding events (e.g. R(2)adj?=?0.59, hooded seal, Cystophora cristata). This likely led to an increase in seal mortality during the breeding period, but also to increase habitat availability for seasonal migratory cetaceans using ice-free areas during winter. We also detected a high frequency of stranding events for mysticete species (minke whale, Balaenoptera acutorostrata) and resident species (beluga, Delphinapterus leucas), correlated with low krill abundance since 1994. Positive NAO indices were positively correlated with high frequencies of stranding events for resident and seasonal migratory cetaceans, as well as rare species (R(2)adj?=?0.53, 0.81 and 0.34, respectively). This contrasts with seal mass stranding numbers, which were negatively correlated with a positive NAO index. In addition, an unusual multiple species mortality event (n?=?114, 62% of total annual mortality) in 2008 was caused by a harmful algal bloom. Our findings provide an empirical baseline in understanding marine mammal survival when faced with climatic variability. This is a promising step in integrating stranding records to monitor the consequences of environmental changes in marine ecosystems over long time scales. PMID:23544059

Truchon, Marie-Hélène; Measures, Lena; L'Hérault, Vincent; Brêthes, Jean-Claude; Galbraith, Peter S; Harvey, Michel; Lessard, Sylvie; Starr, Michel; Lecomte, Nicolas

2013-01-01

415

Ground-water availability from the unconsolidated deposits of the St. Lawrence River Basin, New York  

USGS Publications Warehouse

Protection of New York State 's aquifers has become an increasingly important issue among water resource managers at all levels of State and Local government. Aquifer delineation is necessary as an initial phase in the effective management of the State 's groundwater resources. Many of New York 's productive aquifers consist of unconsolidated deposits. In an effort to obtain complete coverage of all the significant unconsolidated aquifers in New York, the U.S. Geological Survey and the New York State Department of Environmental Conservation began a cooperative study in 1985 to compile groundwater availability maps of each major river basin. This map delineates the unconsolidated aquifers that underlie the State 's northernmost eight counties and gives the estimated potential yield of properly constructed wells completed in these aquifers. Additional well locations and delineation of the aquifers were obtained through a well inventory conducted during the study. (Lantz-PTT)

Bugliosi, Edward F.

1987-01-01

416

A Multi-Scale Analysis of Grassland Bird Habitat Relationships in the St. Lawrence River Valley  

Microsoft Academic Search

I used a combination of 10 vegetation variables and 10 landscape variables to model abundance and occurrence of six grassland bird species in agricultural grassland (n=55) throughout Jefferson County, NY during the 2004 and 2005 field seasons. Landscape composition was quantified by classifying the proportion of land use within a 1 km radius from the center of all survey fields.

Sarah A. Lazazzero

2006-01-01

417

Citizens' Guide to Biomonitoring in the Great Lakes and St. Lawrence River.  

ERIC Educational Resources Information Center

The purpose of this report is to present the issues surrounding biomonitoring of wastewaters discharged into the Great Lakes Basin. Biomonitoring is the process of using organisms to monitor the toxicity of a substance. The report reflects an interest in seeing zero discharge of toxic pollutants in the Great Lakes region. The report is organized…

Great Lakes United, Buffalo, NY.

418

Marine Mammal Strandings and Environmental Changes: A 15-Year Study in the St. Lawrence Ecosystem  

PubMed Central

Understanding the effects of climatic variability on marine mammals is challenging due to the complexity of ecological interactions. We used general linear models to analyze a 15-year database documenting marine mammal strandings (1994–2008; n?=?1,193) and nine environmental parameters known to affect marine mammal survival, from regional (sea ice) to continental scales (North Atlantic Oscillation, NAO). Stranding events were more frequent during summer and fall than other seasons, and have increased since 1994. Poor ice conditions observed during the same period may have affected marine mammals either directly, by modulating the availability of habitat for feeding and breeding activities, or indirectly, through changes in water conditions and marine productivity (krill abundance). For most species (75%, n?=?6 species), a low volume of ice was correlated with increasing frequency of stranding events (e.g. R2adj?=?0.59, hooded seal, Cystophora cristata). This likely led to an increase in seal mortality during the breeding period, but also to increase habitat availability for seasonal migratory cetaceans using ice-free areas during winter. We also detected a high frequency of stranding events for mysticete species (minke whale, Balaenoptera acutorostrata) and resident species (beluga, Delphinapterus leucas), correlated with low krill abundance since 1994. Positive NAO indices were positively correlated with high frequencies of stranding events for resident and seasonal migratory cetaceans, as well as rare species (R2adj?=?0.53, 0.81 and 0.34, respectively). This contrasts with seal mass stranding numbers, which were negatively correlated with a positive NAO index. In addition, an unusual multiple species mortality event (n?=?114, 62% of total annual mortality) in 2008 was caused by a harmful algal bloom. Our findings provide an empirical baseline in understanding marine mammal survival when faced with climatic variability. This is a promising step in integrating stranding records to monitor the consequences of environmental changes in marine ecosystems over long time scales. PMID:23544059

Truchon, Marie-Helene; Measures, Lena; L'Herault, Vincent; Brethes, Jean-Claude; Galbraith, Peter S.; Harvey, Michel; Lessard, Sylvie; Starr, Michel; Lecomte, Nicolas

2013-01-01

419

Assessment of soil erosion in a small agricultural basin of the St. Lawrence River watershed  

Microsoft Academic Search

In the last decades, the conservation of soil and water resources has become a major environmental concern worldwide. The authors used an anthropogenic radiotracer (137Cs) to assess the magnitude and the spatial distribution of soil movement in a 80 ha agricultural watershed located in Southeastern Québec (Canada). This project is part of a larger one aimed at increasing our understanding

L. Mabit; C. Bernard; M. R. Laverdière; S. Wicherek

1999-01-01

420

Geographic signatures of North American West Coast estuaries  

Microsoft Academic Search

West Coast estuaries are geologically young and composed of a variety of geomorphological types. These estuaries range from\\u000a large fjords to shallow lagoons; from large to low freshwater flows. Natural hazards include E1 Niños, strong Pacific storms,\\u000a and active tectonic activity. West Coast estuaries support a wide range of living resources: five salmon species, harvestable\\u000a shellfish, waterfowl and marine birds,

Robert Emmett; ROBERTO LLANSO ´; Jan Newton; Ron Thom; Michelle Hornberger; Cheryl Morgan; Colin Levings; Andrea Copping; Paul Fishman

2000-01-01

421

A statistical–dynamical method for predicting estuary morphology  

Microsoft Academic Search

A statistical–dynamical model for estuary morphodynamics is presented and demonstrated with a case study on the Humber Estuary,\\u000a UK. The model presented here is hybrid in nature where simplified process dynamics are combined with a data-driven approach.\\u000a The modelling methodology uses an inverse technique to construct an unknown source function in the model-governing equation,\\u000a using historic measurements of estuary bathymetry.

Dominic E. Reeve; Harshinie Karunarathna

2011-01-01

422

Degree of Fragmentation Affects Fish Assemblage Structure in Andros Island (Bahamas) Estuaries  

E-print Network

Degree of Fragmentation Affects Fish Assemblage Structure in Andros Island (Bahamas) Estuaries with different degrees of fragmentation on Andros Island, Bahamas. Estuaries were classified a priori into four

Langerhans, Brian

423

Lawrence Livermore National Laboratory Environmental Report 2010  

SciTech Connect

The purposes of the Lawrence Livermore National Laboratory Environmental Report 2010 are to record Lawrence Livermore National Laboratory's (LLNL's) compliance with environmental standards and requirements, describe LLNL's environmental protection and remediation programs, and present the results of environmental monitoring at the two LLNL sites - the Livermore site and Site 300. The report is prepared for the U.S. Department of Energy (DOE) by LLNL's Environmental Protection Department. Submittal of the report satisfies requirements under DOE Order 231.1A, Environmental Safety and Health Reporting, and DOE Order 5400.5, Radiation Protection of the Public and Environment. The report is distributed electronically and is available at https://saer.llnl.gov/, the website for the LLNL annual environmental report. Previous LLNL annual environmental reports beginning in 1994 are also on the website. Some references in the electronic report text are underlined, which indicates that they are clickable links. Clicking on one of these links will open the related document, data workbook, or website that it refers to. The report begins with an executive summary, which provides the purpose of the report and an overview of LLNL's compliance and monitoring results. The first three chapters provide background information: Chapter 1 is an overview of the location, meteorology, and hydrogeology of the two LLNL sites; Chapter 2 is a summary of LLNL's compliance with environmental regulations; and Chapter 3 is a description of LLNL's environmental programs with an emphasis on the Environmental Management System including pollution prevention. The majority of the report covers LLNL's environmental monitoring programs and monitoring data for 2010: effluent and ambient air (Chapter 4); waters, including wastewater, storm water runoff, surface water, rain, and groundwater (Chapter 5); and terrestrial, including soil, sediment, vegetation, foodstuff, ambient radiation, and special status wildlife and plants (Chapter 6). Complete monitoring data, which are summarized in the body of the report, are provided in Appendix A. The remaining three chapters discuss the radiological impact on the public from LLNL operations (Chapter 7), LLNL's groundwater remediation program (Chapter 8), and quality assurance for the environmental monitoring programs (Chapter 9). The report uses System International units, consistent with the federal Metric Conversion Act of 1975 and Executive Order 12770, Metric Usage in Federal Government Programs (1991). For ease of comparison to environmental reports issued prior to 1991, dose values and many radiological measurements are given in both metric and U.S. customary units. A conversion table is provided in the glossary.

Jones, H E; Bertoldo, N A; Campbell, C G; Cerruti, S J; Coty, J D; Dibley, V R; Doman, J L; Grayson, A R; MacQueen, D H; Wegrecki, A M; Armstrong, D H; Brigdon, S L; Heidecker, K R; Hollister, R K; Khan, H N; Lee, G S; Nelson, J C; Paterson, L E; Salvo, V J; Schwartz, W W; Terusaki, S H; Wilson, K R; Woods, J M; Yimbo, P O; Gallegos, G M; Terrill, A A; Revelli, M A; Rosene, C A; Blake, R G; Woollett, J S; Kumamoto, G

2011-09-14

424

Impact of climate change on Gironde Estuary  

NASA Astrophysics Data System (ADS)

Within the THESEUS European project, a simplified mathematical model for storm surge levels in the Bay of Biscay was adjusted on 10 events at Le Verdon using wind and pressure fields from CLM/SGA, so that the water levels at Le Verdon have the same statistic quantiles as observed tide records for the period [1960-2000]. The analysis of future storm surge levels shows a decrease in their quantiles at Le Verdon, whereas there is an increase of the quantiles of total water levels. This increase is smaller than the sea level rise and gets even smaller as one enters farther upstream in the estuary. A numerical model of the Gironde Estuary was then used to evaluate future water levels at 6 locations of the estuary from Le Verdon to Bordeaux and to assess the changes in the quantiles of water levels during the XXIst century using ONERC's pessimistic scenario for sea level rise (60 cm). The model was fed by several data sources : wind fields at Royan and Mérignac interpolated from the grid of the European Climatolologic Model CLM/SGA, a tide signal at Le Verdon, the discharges of Garonne (at La Réole), the Dordogne (at Pessac) and Isle (at Libourne). A series of flood maps for different return periods between 2 and 100 years and for four time periods ([1960-1999], [2010-2039], [2040-2069] and [2070-2099]) have been built for the region of Bordeaux. Quantiles of water levels in the floodplain have also been calculated. The impact of climate change on the evolution of flooded areas in the Gironde Estuary and on quantiles of water levels in the floodplain mainly depends on the sea level rise. Areas which are not currently flooded for low return periods will be inundated in 2100. The influence of river discharges and dike breaching should also be taken into account for more accurate results.

Laborie, Vanessya; Hissel, François; Sergent, Philippe

2014-05-01

425

Sources of Heavy Metal Pollution into the St. Louis River, Lake Superior Watershed  

NASA Astrophysics Data System (ADS)

The St. Louis River begins in Hoyt Lakes, Minnesota and enters Lake Superior between Duluth, Minnesota and Superior, Wisconsin. The Partridge River and the Embarrass River are two of its main tributaries. National Pollutant Discharge Elimination System (NPDES) permits are issued for surface water dischargers under the Clean Water Act. The Permit Compliance System (PCS) and the Integrated Compliance Information System (ICIS) is a tool allowing public access to information contained in NPDES permits. Along the way to Lake Superior, 19 facilities list the St. Louis River, St. Louis Bay, part of the St. Louis River estuary, or one of its tributaries as a receiving water. Of these 19 locations, four report discharging heavy metals into the receiving water. Copper and Lead are the metals most frequently discharged.

Sternberg, S. P.; Palokangas, C.

2013-12-01

426

Seasonal Trends in Abundance and Size of Juvenile American Shad, Hickory Shad, and Blueback Herring in the St. Johns River, Florida, and Comparison with Historical Data  

Microsoft Academic Search

American shad Alosa sapidissima, hickory shad A. mediocris, and blueback herring A. aestivalis spawn in Florida's St. Johns River during winter and spring, and juveniles migrate out of the estuary during the following fall. We assessed the temporal trends of juvenile relative abundance and size as each species moved downstream past Palatka, Florida, and compared these values to historical data

Nicholas A. Trippel; Micheal S. Allen; Richard S. McBride

2007-01-01

427

21st Century Scholars  

ERIC Educational Resources Information Center

Bethpage Union Free School District in New York is a high-performing district by almost any current accountability measure. Yet administrators and teachers worried that they were not doing enough to prepare their students as critical thinkers for the 21st century. Inspired by the curriculum framework of the Partnership for 21st Century Skills, the…

Clark, Terrence

2009-01-01

428

WESTERN BLVD HILLSBOROUGH ST  

E-print Network

BLVD Miller Field PQ Fox Doak Field Mackenzie Timber Baffin DH Hill Arctic Hudson Red Weaver Caspian BURRELL PL M OTOR POOL ST ROSEMARYST CHAPPELLDR TREXLER CT HELIX CT DOUGLAS ST FOX STERLING DR SHEPHERDST Nelson EHS Scott Schaub Butler Engr Bldg II Mann J F C E Red Hat Leazar McKimmon Exten Ed Ct Brooks

Young, R. Michael

429

Courses & Curricula Committee Membership 2013 Lawrence Rouse, Chair  

E-print Network

Courses & Curricula Committee Membership 2013 Lawrence Rouse, Chair School of Coast & Environment Registrar Andy Nyman, Ex-Officio General Education Committee Chair Anna Castrillo, Administrative of Mass Communication Pamela Pike, Member College of Music & Dramatic Arts John Hopkins, Member College

Harms, Kyle E.

430

FROM INTERSECTION OF GREGORY STREET AND LAWRENCE STREET NEAR EASTERN ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FROM INTERSECTION OF GREGORY STREET AND LAWRENCE STREET NEAR EASTERN EDGE OF CENTRAL CITY ON GREGORY GULCH, VIEW TOWARDS SOUTHWEST, FOREGROUND IS RETAINING WALL FOR GREGORY STREET - Central City, Central City, Gilpin County, CO

431

Newsblaster Russian-English Clustering Performance Analysis Lawrence J. Leftin  

E-print Network

Newsblaster Russian-English Clustering Performance Analysis Lawrence J. Leftin Department of Computer Science Columbia University, New York Abstract: The Natural Language Group is developing a multi sites. Newsblaster currently processes articles in Arabic, Japanese, Portuguese, Spanish, and Russian

432

Building Footprints (Shapefile) of University of Kansas, Lawrence Campus  

E-print Network

Data layer geneated with Intention to have basic building dataset for data analysis and generation of maps, for Lawrence Campus of the University of Kansas. Building outlines were digitized using ArcMap in ca. 2007 from ...

Houser, Rhonda; Havercamp, Curtis

2011-02-18

433

The HARP software library and utility package A E Lawrence  

E-print Network

The HARP software library and utility package A E Lawrence March 18, 1996 #12; Contents 1 libraries 20 5.1 network.inc and harp1con : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 20 5.2 harp1dec : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 21 5.3 ispdec

Lawrence, Adrian

434

FY2011 Sensitive Property List Lawrence Berkeley National Laboratory  

E-print Network

FY2011 Sensitive Property List Lawrence Berkeley National Laboratory February 1, 2011 Sensitive regardless of its acquisition cost. Sensitive property must be barcode tagged and is subject to Laboratory

435

COACHE Survey Results Lawrence S. Bloomberg Faculty of  

E-print Network

satisfaction � Look at differences in experience by rank and gender � Identify impact of policies and processesCOACHE Survey Results Lawrence S. Bloomberg Faculty of Nursing May 28, 2014 #12;The COACHE Survey

Toronto, University of

436

Restaurant Growth in Lawrence, Kansas, 1950 to 2007  

E-print Network

in restaurants and bars was almost twice as important in Douglas County as it was nationaly (Bureau of Labor Statistics, 2008). My research is historicaly based, focusing on questions related to the growth rate of restaurants compared to that of the population..., the archivist of the Watkins Community Museum, authors of The KU/Lawrence Trivia Quiz Book, and several present and former restaurant owners in Lawrence. I also interviewed at four local retirement and asisted living communities: Brandon Woods Retirement...

Brackhan, Jennifer L.

2009-01-22

437

Lawrence Berkeley National Laboratory U.S. Department of Energy | Office of Science Programmable Information Highway  

E-print Network

Lawrence Berkeley National Laboratory U.S. Department of Energy | Office of Science Programmable Lawrence Berkeley National Lab #12;Lawrence Berkeley National Laboratory U.S. Department of Energy | Office Is there an impedance mismatch? #12;Lawrence Berkeley National Laboratory U.S. Department of Energy | Office of Science

438

The Hydrography of the Chupa Estuary, White Sea, Russia  

Microsoft Academic Search

This study was undertaken to determine the fate and fluxes of materials from Arctic estuaries to the coastal zone. The paper is the first of a series addressing questions relating to the physics and chemistry of the region. Three seasonal cruises were undertaken in the Chupa Estuary, White Sea, Russia; in summer (July 1994), autumn (September, 1995) and spring (May\\/June

R. J. M. Howland; A. N. Pantiulin; G. E. Millward; R. Prego

1999-01-01

439

Fate of methane in the Hudson River and estuary  

Microsoft Academic Search

Methane (CH4) concentrations and oxidation rates were measured throughout the Hudson River Estuary in March and August of 1991. Methane concentrations ranged from 50 to 940 nM and were supersaturated with respect to the atmosphere along the entire length of the river, with generally higher CH4 values in the lower, saline portion of the estuary. A seasonally averaged diffusive flux

Marie A. de Angelis; Mary I. Scranton

1993-01-01

440

Behavior of metals in the Amur River estuary  

Microsoft Academic Search

Biogeochemical processes in estuaries determine to a significant extent the further life of chemical compounds, including metals transported by rivers. Therefore, the characteristics of the behavior of metals in waters with intermediate salinity at the river?sea interface have both scientific and practical significance [1?5]. In terms of estimation of the concentrations of dissolved metals, the estuary of the Amur River,

V. M. Shul’kin

2006-01-01

441

LOWER COLUMBIA RIVER ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

An estuary is the area where the fresh water of a river meets the salt water of an ocean. In the Columbia River system, this occurs in the lower 46 river miles. In an estuary, the river has a direct, natural connection with the open sea. This transition from fresh to salt water c...

442

Real time simulation of nitrogen cycle in an estuary  

Microsoft Academic Search

A water quality model containing seven nitrogen storage variables appropriate to an aerobic, nitrogen limited, aquatic ecosystem is described. An idealized estuary is used to demonstrate coupling between hydrodynamic transport, mixing, and biochemical transformations. Nutrient concentrations are highly sensitive to the representation of real time (intratidal cycle) transport. Application of the model to the Potomac estuary illustrates the large temporal

T. O. Najarian; D. R. F. Harleman

1977-01-01

443

Flood and ebb dominance in estuaries in Korea  

Microsoft Academic Search

Ebb dominance, which is mainly observed at the Youngsan River estuary (YRE) and flood dominance at the Keum River estuary (KRE) are conspicuous features in the southwestern coastal zones of Korea. In considering the sources of this asymmetry, which include, not only bottom friction, irregular bathymetry and tidal flats, other issues also need to be considered, since dominance occurs extensively

J. W Kang; K. S Jun

2003-01-01

444

Primary Productivity Regime and Nutrient Removal in the Danube Estuary  

Microsoft Academic Search

The primary productivity regime, as well as the distribution of dissolved inorganic nutrients and particulate organic matter in the Danube estuary, were investigated during several cruises at different discharge regimes of the Danube River. The shallowness of the upper surface layer due to insignificant tidal mixing and strong stratification of the Danube estuary, as well as the high nutrient concentrations,

C. Humborg

1997-01-01

445

ASSESSING THE ECOLOGICAL CONDITION OF SOUTHEAST U. S. ESTUARIES  

EPA Science Inventory

As a means to assess ecological condition, 151 stations located in southeastern estuaries from Cape Henry, Virginia to Biscayne Bay, Florida were sampled by state agencies during the summer of 2000 using a probabilistic design. The design used 8 size classes of estuaries ranging ...

446

YAQUINA BAY AND BEYOND: WHAT SHAPE ARE OUR ESTUARIES IN?  

EPA Science Inventory

The great natural beauty of Oregon's estuaries gives an impression of systems that are far less altered than those in other areas of the US. However, over the years, Yaquina Bay and other western estuaries have been variously affected by habitat loss and alteration, over harvest...

447

LIMNETIC LARVAL FISH OF THE MAUMEE AND SANDUSKY RIVER ESTUARIES  

EPA Science Inventory

A total of 17 taxa were collected in the Maumee River estuary during sampling periods in 1975, 1976, and 1977. A total of 11 taxa were collected from the Sandusky River estuary in 1976. Gizzard shad/alewife, Dorosoma cepedianum/Alosa pseudoharengus, white bass/white perch, Morone...

448

Controlling Invasive Cordgrasst A Tale of Two Estuaries  

Microsoft Academic Search

Open intertidal mud is a hallmark of Pacific estuaries. Shore birds, marine life, and the traditional fishing and oystering in these habitats depend upon openness. Alien cordgrasses of the genus Spartina threaten these estuaries. Growing further down the intertidal gradient than any other land plant, Spartina alterniflora (Smooth Cordgrass, introduced from the Atlantic coast) and Spartina anglica (English Cordgrass, introduced

Donald R. Strong; Debra R. Ayres

449

PECONIC ESTUARY: RECREATIONAL AND RESOURCE ECONOMIC VALUES FOR THE PECONIC ESTUARY SYSTEM  

EPA Science Inventory

The environmental and natural resources ("natural assets") of the Peconic Estuary System--the bay waters, beaches, wetlands, ecosystems, habitats, and parks and watershed lands--provide many services to the public. Outdoor recreation, scenic views, and the productivity of wetland...

450

Approaches for Development of Nutrient Criteria in Oregon Estuaries With a Focus on Tillamook Estuary  

EPA Science Inventory

Development of nutrient criteria for all water body types of the US remains a top priority for EPA. Estuaries in the Pacific Northwest receive nutrients from both the watershed and the coastal ocean, and thus are particularly complex systems in which to establish water quality c...

451

CCD Camera Operating Manual Model ST-4X, ST-5 and ST-6  

E-print Network

CCD Camera Operating Manual for the Model ST-4X, ST-5 and ST-6 Santa Barbara Instrument Group 1482 .................................................................................1 1.2.2. CCD Camera..........................................................................................2 2. Introduction to CCD Cameras

452

A hybrid approach to estimate chromophoric dissolved organic matter in turbid estuaries from  

E-print Network

A hybrid approach to estimate chromophoric dissolved organic matter in turbid estuaries from to derive CDOM absorption coefficient at 443 nm (ag(443), m-1 ) in a turbid estuary (Tampa Bay) from MODIS discharge. Testing of the approach over another turbid estuary (Chesapeake Bay, the largest estuary in the U

Meyers, Steven D.

453

Salmon Life Histories, Habitats, and Food Webs in the Columbia River Estuary  

E-print Network

Salmon Life Histories, Habitats, and Food Webs in the Columbia River Estuary Daniel J. Bottom NOAA management efforts in the Columbia River estuary on behalf of salmon: (1) the estuary is irrelevant stocks throughout the Columbia River Basin. The Columbia River estuary contributes to salmon life history

454

AN APPROACH TO DEVELOPING NUTRIENT CRITERIA FOR PACIFIC NORTHWEST ESTUARIES: A CASE STUDY OF YAQUINA ESTUARY, OREGON  

EPA Science Inventory

NHEERL scientists have developed an approach that could be used by the State of Oregon for development of nutrient and other water quality criteria for the Yaquina Estuary, Oregon. The principle objective in setting protective criteria is to prevent future degradation of estuari...

455

Mercury sources and transformations in a man-perturbed tidal estuary: The Sinnamary Estuary, French Guiana  

NASA Astrophysics Data System (ADS)

The distribution, partition and speciation of mercury (Hg) were studied along the redox gradient of an anthropogenically perturbed tropical estuary, the Sinnamary Estuary in French Guiana. This system is a partially mixed estuary characterized by an anoxic freshwater end-member, while the marine end-member consists of the Amazon Plume. The set up of an artificial oxygenation system in the anoxic freshwater end-member generates sharp gradients of major chemical species (iron, sulfides, etc.) coupled with intense organic matter (OM) turnover. The coexistence of oxygenated waters and dissolved sulfides in an organic rich environment depicts the Upper Sinnamary Estuary (USE: part of Sinnamary Estuary under the tidal influence but upstream of the salt intrusion) as a potential site for Hg methylation. The concentrations of all mercury compounds (HgT) in the unfiltered samples (HgT UNF), in the dissolved (HgT D) and particulate (HgT P) phases of the USE average 11 ± 3, 6 ± 2 and 5 ± 3 (i.e. 600 ± 200 pmol g -1) pmol L -1, respectively. Average concentrations of monomethylmercury (MMHg) in the unfiltered (MMHg UNF), dissolved (MMHg D) and particulate (MMHg P) phases were 3.7 ± 1.0, 2.0 ± 0.9 and 1.8 ± 1.2 (i.e. 220 ± 130 pmol g -1) pmol L -1, respectively. Water oxygenation and sulfides concentrations emerged to play a critical role in controlling MMHg levels. Additionally, iron cycling, acid-base mechanisms, and redox-dependent processes were involved in the MMHg partitioning between phases. Overall, the USE constitutes a biogeochemical reactor that gathers partitioning and methylation processes. The permanent MMHg inputs from the anoxic freshwater end-member combined with the intense endogenous Hg methylation ensures high-MMHg levels in both dissolved and particulate phases. To illustrate, the USE exports 60 ± 20% more MMHg UNF than it imports: 5.5 ± 0.7 vs. 3.5 ± 1.2 kg year -1.

Muresan, B.; Cossa, D.; Coquery, M.; Richard, S.

2008-11-01

456

Final report for sea-level rise response modeling for San Francisco Bay estuary tidal marshes  

USGS Publications Warehouse

The International Panel on Climate Change has identified coastal ecosystems as areas that will be disproportionally affected by climate change. Current sea-level rise projections range widely with 0.57 to 1.9 meters increase in mea sea level by 2100. The expected accelerated rate of sea-level rise through the 21st century will put many coastal ecosystems at risk, especially those in topographically low-gradient areas. We assessed marsh accretion and plant community state changes through 2100 at 12 tidal salt marshes around San Francisco Bay estuary with a sea-level rise response model. Detailed ground elevation, vegetation, and water level data were collected at all sites between 2008 and 2011 and used as model inputs. Sediment cores (taken by Callaway and others, 2012) at four sites around San Francisco Bay estuary were used to estimate accretion rates. A modification of the Callaway and others (1996) model, the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER), was utilized to run sea-level rise response models for all sites. With a mean sea level rise of 1.24 m by 2100, WARMER projected that the vast majority, 95.8 percent (1,942 hectares), of marsh area in our study will lose marsh plant communities by 2100 and to transition to a relative elevation range consistent with mudflat habitat. Three marshes were projected to maintain marsh vegetation to 2100, but they only composed 4.2 percent (85 hectares) of the total marsh area surveyed.

Takekawa, John Y.; Thorne, Karen M.; Buffington, Kevin J.; Spragens, Kyle A.; Swanson, Kathleen M.; Drexler, Judith Z.; Schoellhamer, David H.; Overton, Cory T.; Casazza, Michael L.

2013-01-01

457

MAIA Estuaries 1997-98 Data  

NSDL National Science Digital Library

The Mid Atlantic Integrated Assessment program (MAIA) of the Environmental Protection Agency (EPA) has released these estuaries data for 1997-98. Data and Metadata may be viewed or downloaded (text or .pdf) for the following variables: Sampling Station Location Data, Station Visit Data, Water Quality Physical Measurements, Water Quality- Nutrients Data, Sediment Grain Size Data, Sediment Toxicity Data, Sediment Chemistry Data, Benthic Community Grain Size Data, Benthic Abundance Data, Benthic Biomass Data, Benthic Community Summary Data, Chemical Analyte Code Table, and Benthic Taxon Code Table.

458

St. Paul's Cathedral  

NSDL National Science Digital Library

Perhaps one of the finest neo-Classical cathedrals in the world, the current St. Paul's cathedral is an example of the outstanding architecture of Christopher Wren, and a testimony to his dogged persistence and passion for his life's work. In keeping with the attention to detail that is indicative of Mr. Wren's work, the St. Paul's Web site has detailed information on visiting the cathedral, the various musical performances that it hosts, and an interactive timeline detailing the history of St. Paul's that extends back to the year 604. Along with this information, the site also tells visitors about upcoming events at the cathedral, along with an extensive online gift shop that offers a diverse set of St. Paul's related material for purchase.

459

St.Louis  

Cancer.gov

Skip to Main Content Headlines Pediatric Oncology Branch Home > Pediatric Psycho-Oncology Professionals > Training Headline Title Pediatric Psycho-Oncology Professionals Pediatric Psychologist, Hem/Onc St. Louis Children's Hospital The Psychology Department

460

Obituary: Fred Lawrence Whipple, 1906-2004  

NASA Astrophysics Data System (ADS)

Fred Whipple, one of the founding fathers of planetary science, died on August 30, 2004 just two months shy of his 98th birthday. The breadth of Fred's published research from 1927 through 2000 is quite extraordinary. Although his collected works were published in two massive volumes in 1972, shortly before his retirement, Fred's research contributions continued for another three decades - and another volume is planned. Fred Lawrence Whipple was born on November 5, 1906 on a farm in Red Oak Iowa. His parents were Harry Lawrence and Celestia (MacFarl) Whipple. At the age of fifteen, the Whipple family moved to California where Fred studied mathematics at Occidental College and the University of California at Los Angeles. As a graduate student at the University of California at Berkeley in 1930, he was one of the first to compute an orbit for the newly discovered planet Pluto. Upon receiving his PhD in 1931, he joined the staff of the Harvard College Observatory. He was Chairman of the Harvard Department of Astronomy (1949 - 1956), Director or the Smithsonian Astrophysical Observatory (1955 - 1973), Phillips Professor of Astronomy (1968 - 1977) and Emeritus Phillips Professor of astronomy (1977 - 2004). In 1928 he married Dorothy Woods and their son, Earle Raymond, survives him. The marriage ended in divorce in 1935. Eleven years later, he married Babette F. Samelson and she too survives him, as do their two daughters Laura and (Dorothy) Sandra. Shortly after arriving at Harvard in the early 1930's, Fred developed a photographic tracking network to determine meteor trajectories from simultaneous observations from two or more stations. The photographic trails, chopped by a rotating shutter, allowed their orbits in space to be determined accurately. With the strong involvement of Richard McCrosky and others, he concluded in the early 1960's that most of these meteors were on comet-like orbits and less than 1% of the naked eye, sporadic meteors could be traced to an origin outside the solar system. To fill the daytime gap when meteors could not be photographed, Fred organized a program for the radio detection of these objects. With the launch of Sputnik in October 1957, Whipple's visual network of amateur astronomers (Moon watch) was already in place to follow its progress and later on he developed an optical tracking system for meteors and artificial satellites using wide field, Baker-Nunn cameras. This latter system proved so successful that the precision tracking of these satellites could be used to model the Earth's shape and density variations from the observed gravitational effects upon these satellite orbits. He once noted that the highlight of his career was having his family and parents present at the White House while he received the President's Award for Distinguished Public Service from John F. Kennedy for this work. His seminal works in 1950-51 on the icy conglomerate model for the cometary nucleus prompted a complete paradigm switch. Until then, the current consensus model for a comet was a flying cloud of particles; it had been so since the second half of the nineteenth century when comets were identified with meteor showers. He envisaged the cometary nucleus as a conglomerate of ices (mostly water, ammonia, methane, carbon dioxide and carbon monoxide ices) embedded within, and covered over with, a nonvolatile matrix of meteoric material. Part of his rationale for developing this "dirty snowball" model for the cometary nucleus was to provide an explanation of the so-called nongravitational forces acting upon comets. The rocket-like thrusting of a comet when the ices vaporize near the sun introduced a small, but noticeable, thrust on the comet itself and when this effect was properly modeled, the motions of active comets could be predicted far more accurately. Subsequent spacecraft ultraviolet observations showing enormous cometary hydrogen atmospheres confirmed that the major cometary ice was likely to be water. The 1986 Giotto spacecraft images, revealing a solid cometary nucleus (albeit far blacker

Yeomans, Donald Keith

2004-12-01