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1

Circulation and Mixing in the St. Lawrence Estuary  

E-print Network

Circulation and Mixing in the St. Lawrence Estuary by Daniel Bourgault Department of Atmospheric in the St. Lawrence Estuary are examined using both newly acquired and historical observations, as well of a three-dimensional numerical model on the occurrences of shear instabilities within the upper estuary

Bourgault, Daniel

2

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

3

A numerical model for water level oscillations in the St. Lawrence estuary, Canada Part II: Tsunamis  

Microsoft Academic Search

The St. Lawrence estuary in eastern Canada has been historically a seismic region, and a major earthquake in or near the estuary could generate a strong tsunami. At present there is no warning system in place for tsunami prediction in the estuary. The present study was conducted to provide some of the much needed information on possible tsunami amplitudes and

J. Chassé; T. S. Murty

1993-01-01

4

Mesoscale physical—biological variability during a summer phytoplankton bloom in the lower St Lawrence Estuary  

Microsoft Academic Search

Wide estuaries can produce and sustain eddies that can then have a substantial impact on the fluxes of nutrients and on the production and export of carbon. As part of a multidisciplinary programme to evaluate the biological impact of cold-core eddies in the lower St Lawrence Estuary, six cruises were conducted between mid-June and mid-July 1989, during the period of

Alain F Vézina; Yves Gratton; Pierre Vinet

1995-01-01

5

Cancer in Wildlife, a Case Study: Beluga from the St. Lawrence Estuary, Québec, Canada  

Microsoft Academic Search

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

Daniel Martineau; Karin Lemberger; André Dallaire; Philippe Labelle; Thomas P. Lipscomb; Pascal Michel; Igor Mikaelian

2002-01-01

6

A numerical model for water level oscillations in the St. Lawrence estuary, Canada Part I: Tides  

Microsoft Academic Search

A two?dimensional time?dependent nonlinear tidal model was developed for the St. Lawrence estuary, with two open boundaries. This model is a substantial improvement over two earlier models which did not include the nonlinear terms. The model is run simultaneously, to hindcast the tide on any particular day, using as boundary conditions real data for the five important constituents, namely M2,

J. chassé; T. S. Murty

1993-01-01

7

Dermatophilus-like infection in beluga whales, Delphinapterus leucas, from the St. Lawrence estuary.  

PubMed

Six beluga whales (Delphinapterus leucas) found dead on the shores of the St. Lawrence estuary had multiple slightly depressed greyish round areas randomly distributed over the whole body. Histologically, the surface of these areas was covered with a thick layer of Dermatophilus-like organisms which invaded the stratum corneum. The underlying stratum spinosum had marked spongiosis and vacuolar degeneration. Minimal neutrophilic infiltration was present within the underlying dermal papillae. To the authors' knowledge, dermatophilosis in cetaceans has not been reported previously. PMID:11301540

Mikaelian, I; Lapointe, J M; Labelle, P; Higgins, R; Paradis, M; Martineau, D

2001-02-01

8

Oceanography and Quaternary geology of the St. Lawrence Estuary and the Saguenay Fjord This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-print Network

Oceanography and Quaternary geology of the St. Lawrence Estuary and the Saguenay Fjord This article of the St. Lawrence Estuary and the Saguenay Fjord Anne de Vernal1 , Guillaume St-Onge2 and Denis Gilbert3 1. The St. Lawrence Estuary is an environment marked by important freshwater discharge and well stratified

St-Ong, Guillaume

9

Trophic interactions in the St. Lawrence Estuary (Canada): Must the blue whale compete for krill?  

NASA Astrophysics Data System (ADS)

Inverse methodology was used to construct a mass-balance model of the Lower St. Lawrence Estuary (LSLE) for the 2008-2010 time period. Our first objective was to make an overall description of community structure, trophic interactions, and the effects of fishing and predation on the vertebrate and invertebrate communities of the ecosystem. A second objective was to identify other important predators of krill, and to assess if these compete with blue whales, listed as endangered under the Canadian Species at Risk Act in 2005 (northwest Atlantic population). The Estuary and the Gulf of St. Lawrence are summer feeding grounds for blue whales and other marine mammals. Blue whales eat only euphausiids (krill) and require dense concentrations of prey to meet their energy requirements, which makes them particularly vulnerable to changes in prey availability. In the LSLE, many species from secondary producers (hyperiid amphipods, other macrozooplankton) to top predators (fish, birds, and marine mammals) consumed euphausiids. Consequently, krill predators were found at all consumer trophic levels. However, our results showed that only about 35% of the estimated euphausiid production was consumed by all predator species combined. Euphausiid did not seem to be a restricted resource in the LSLE ecosystem, at least during the study period. The blue whale did not appear to have to compete for krill in the LSLE.

Savenkoff, C.; Comtois, S.; Chabot, D.

2013-09-01

10

Immunotoxicity in plaice exposed to marine sediments in Baie des Anglais on the St. Lawrence Estuary  

SciTech Connect

The sediments of Baie des Anglais on the St. Lawrence Estuary have a history of environmental contamination. The purpose of the present study was to determine whether or not the immune system of American Plaice (Hippoglossoides Platessoides) could be affected following in-situ exposure at three different sites in and near Baie des Anglais. These sites vary with their proximity to local industry, Sites 1 and 2 (within the bay) being the closest and Site 3 (outside the bay) the furthest away. Fishes placed in cages at each site for three weeks, displayed head kidney cell immune responses (i.e., phagocytosis) modifications indicating that Site 1 was most immunotoxic and site 3 the least. Sediment chemical analysis show a gradient in contaminant concentrations with the highest levels recorded at Site 1, about 10-fold less at Site 2 and 100-fold less at Site 3. Organics predominated (PAHs, PCBs, PCDFs) with heavy metal concentrations low and representative of background levels for the St. Lawrence Estuary. The results obtained indicate that contaminants present in the sediments are bioavailable to fish and significantly affect their immune system.

Lacroix, A. [Univ. of Quebec, Montreal, Quebec (Canada); Nagler, J.; Lee, K.; Lebeuf, M.; Cyr, D. [Fisheries and Oceans Canada, Mont-Joli, Quebec (Canada); Fournier, M. [Univ. of Quebec, Montreal, Quebec (Canada); [Fisheries and Oceans Canada, Mont-Joli, Quebec (Canada)

1995-12-31

11

Toxoplasmosis in Beluga Whales ( Delphinapterus leucas ) from the St Lawrence Estuary: Two Case Reportsand a Serological Survey  

Microsoft Academic Search

Toxoplasmosis was diagnosed in two free-ranging beluga whales from the St Lawrence estuary, Quebec, Canada, in 1988 and 1998. Histologically, tachyzoites and bradyzoites were present in the brain, spleen, lymph nodes, adrenals and lungs of both animals, and in the thymus of one. These organisms were readily labelled by an indirect immunohistochemical method for Toxoplasma gondii antigens. In the lymph

I Mikaelian; J Boisclair; JP Dubey; S Kennedy; D Martineau

2000-01-01

12

Geomorphological characteristics and variability of Holocene mass-transport complexes, St. Lawrence River Estuary, Canada  

NASA Astrophysics Data System (ADS)

Recently acquired multibeam bathymetry data are used to investigate seafloor instability features along a 310 km-long segment of the St. Lawrence River Estuary. The analysis of this dataset indicates that submarine slides occur over a much larger area than previously recognized and that Holocene sediments are reworked by mass-transport along significant portions of both the northwest and southeast margins of the Laurentian Channel. In the surveyed area, 96 individual mass-transport complexes (MTCs) were identified representing 13% of the seabed. MTCs vary in area from less than 1 km2 to more than 40 km2 and exhibit various geomorphological signatures. Qualitative observation reveals an apparent disparity between MTCs that remain coherent and those that disintegrate during downslope transport evolving into a blocky morphological signature. For all MTCs, morphological parameters have been measured (area, length, and height) or calculated (slope and roughness). This quantitative analysis provides a unique opportunity to study these parameters in a statistically significant and homogeneous dataset located in a relatively small area that experienced a similar Quaternary history. In many cases, mass transport events appear to initiate in the vicinity of steep bedrock walls located along some segments of the estuary. The timing of mass-transport events was not constrained during this study. However, the fact that the region hosts the Charlevoix seismic zone, the most tectonically active area in eastern Canada, strongly suggests that earthquakes acted as a trigger for submarine landsliding.

Pinet, Nicolas; Brake, Virginia; Campbell, Calvin; Duchesne, Mathieu J.

2015-01-01

13

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

14

Toxoplasmosis in beluga whales (Delphinapterus leucas) from the St Lawrence estuary: two case reports and a serological survey.  

PubMed

Toxoplasmosis was diagnosed in two free-ranging beluga whales from the St Lawrence estuary, Quebec, Canada, in 1988 and 1998. Histologically, tachyzoites and bradyzoites were present in the brain, spleen, lymph nodes, adrenals and lungs of both animals, and in the thymus of one. These organisms were readily labelled by an indirect immunohistochemical method for Toxoplasma gondii antigens. In the lymph nodes, spleen and lungs the organisms were associated with histiocytic infiltration. In the brain of one animal they were associated with mild multifocal gliosis and haemorrhages. There was no evidence of concomitant morbillivirus infection. Serum samples were collected from 22 beluga whales stranded between 1995 and 1998 on the shores of the St Lawrence Estuary and examined for antibodies to T. gondii by the modified agglutination test. Antibody titres of s25 were found in six (27%) of the animals. This is the first confirmed report of toxoplasmosis in beluga whales. PMID:10627393

Mikaelian, I; Boisclair, J; Dubey, J P; Kennedy, S; Martineau, D

2000-01-01

15

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

16

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

17

Cancer in wildlife, a case study: beluga from the St. Lawrence estuary, Québec, 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, André; Labelle, Philippe; Lipscomb, Thomas P; Michel, Pascal; Mikaelian, Igor

2002-01-01

18

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

PubMed

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, André; Labelle, Philippe; Lipscomb, Thomas P; Michel, Pascal; Mikaelian, Igor

2002-03-01

19

Adenomatous hyperplasia of the thyroid gland in beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary and Hudson Bay, Quebec, Canada.  

PubMed

We evaluated thyroid gland lesions in beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary (n = 16) and Hudson Bay (n = 14). Follicular cysts and nodules of adenomatous hyperplasia of the thyroid gland were found in eight and nine adults from the St. Lawrence Estuary (n = 10), respectively, and in four and six adults from Hudson Bay (n = 14), respectively. The total volume of the lesions of thyroid adenomatous hyperplasia was positively correlated with age in both populations. Comparison between populations could not be performed because of differences in age structures of sample groups. Beluga whales from both populations have unique thyroid lesions among marine mammals. PMID:14608025

Mikaelian, I; Labelle, P; Kopal, M; De Guise, S; Martineau, D

2003-11-01

20

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

21

Stable isotope evidence for glacial lake drainage through the St. Lawrence Estuary, eastern Canada, ~13.1-12.9 ka  

USGS Publications Warehouse

Postglacial varved and rhythmically-laminated clays deposited during the transition from glacial Lake Vermont (LV) to the Champlain Sea (CS) record hydrological changes in the Champlain-St. Lawrence Valley (CSLV) at the onset of the Younger Dryas ?13.1–12.9 ka linked to glacial lake drainage events. Oxygen isotope (?18O) records of three species of benthic foraminifera (Cassidulina reniforme, Haynesina orbiculare, Islandiella helenae) from six sediment cores and the freshwater ostracode Candona from one core were studied. Results show six large isotope excursions (?0.5 to >2‰) in C. reniforme ?18O values, five excursions in H. orbiculare (<0.5 to ?1.8‰), and five smaller changes in I. helenae (<0.5‰). ?18O values in Candona show a 1.5–2‰ increase in the same interval. These isotopic excursions in co-occurring marine and freshwater species in varve-like sediments indicate complex hydrological changes in the earliest Champlain Sea, including brief (sub-annual) periods of complete freshening. One hypothesis to explain these results is that multiple abrupt freshwater influx events caused surface-to-bottom freshening of the Champlain Sea over days to weeks. The most likely source of freshwater would have been drainage of the Morehead Phase of glacial Lake Agassiz, perhaps in a series of floods, ultimately draining out the St. Lawrence Estuary.

Cronin, T. M.; Rayburn, J.A.; Guilbault, J.-P.; Thunell, R.; Franzi, D.A.

2012-01-01

22

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

23

Habitat use and movements of postfledging American black ducks (Anas rubripes) in the St. Lawrence estuary, Quebec  

USGS Publications Warehouse

We used radiotelemetry to determine habitat use and movements of 38 female juvenile American black ducks (Anas rubripes) on the north shore of the St. Lawrence estuary, Quebec, from 28 August to 15 November 1991. Ducks separated into three groups based on habitat use: inland, estuarine, and those using a mixture of habitats. Ducks using mixed habitats used the greatest variety of habitat types, flew the greatest distances and most often between night roosts and day foraging areas, and were unlikely to be shot. The mean distance flown between night-use and day-use areas for all ducks increased nearly 50% after the hunting season began (overall mean = 6104 m, range 1500 - 26384 m). Mean home range size was 27.6 t 6.5 (SE) km2. Ducks exhibited stronger fidelity to wetlands used at night than to those used during the day. Ducks that were shot spent a high percentage of their time on the estuary (90.1 t 7.4 %) and exhibited high fidelity to a day-use area before the hunting season (73 t 7.3 %).

Clugston, D.A.; Longcore, J.R.; McAuley, D.G.; Dupuis, P.

1994-01-01

24

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

25

Chronology of Land Use Change and Industrial Activity in the St. Lawrence Estuary and Saguenay Fjord From the European Settlement to the Present  

NASA Astrophysics Data System (ADS)

Geochemical (organic and inorganic carbon contents), isotopic (13C content of organic matter, 210Pb, 14C), micropaleontological (foraminifera, pollen) and sedimentological analysis of several sedimentary sequences (box and piston cores) were used to determine the chronology of land use change and industrial activity in the St. Lawrence Estuary and Saguenay Fjord from the European settlement to the present. In the St. Lawrence Estuary, the chronostratigraphy was derived from 210Pb and AMS 14C measurements, geochemical and isotopic correlations and the relative abundance of the pollen Ambrosia, whereas the Saguenay Fjord chronological framework was derived from chronostratigraphic markers associated with the 1663 (M~7) earthquake, 1971 St-Jean-Vianney landslide and the flood of 1996. In both area, paper mill and industrial activity during the 20th century is reflected by the organic carbon (OC) and 13C content profiles and has resulted in terrestrial OC contents growing almost exponentially until the 1970's, when major changes in industrial practices and the implementation of environmental regulations reduced the amount of industrial OC discharged into the Fjord and St. Lawrence River. This reduction of industrial waste inputs is also depicted in the Saguenay Fjord sediments by the decline in the relative abundance of the benthic foraminifera Spiroplectammina biformis, an opportunistic and tolerant species previously associated with polluted benthic environments. In addition, major changes in grain size are recorded in a core sampled at the head of the Fjord and probably reflect the impact of dam construction on the Saguenay River discharge. Finally, the chronology of deforestation and agricultural development linked to the European settlement in the St. Lawrence Lowlands as well as the industrial development of the second half of the 20th century are highlighted in the St. Lawrence Estuary sediments by the increase in the relative abundance of the pollen Ambrosia and by the two-step increase in sedimentation rates from 0.15 to 0.28 cm/yr and finally to 0.74 cm/yr.

St-Onge, G.; Hillaire-Marcel, C.; de Vernal, A.; Leduc, J.; Mucci, A.

2004-05-01

26

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

27

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

28

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

29

Recent transfer of coastal sediments to the Laurentian Channel, Lower St. Lawrence Estuary (Eastern Canada),  

E-print Network

(Eastern Canada), through submarine canyon and fan systems Hubert Gagné & Patrick Lajeunesse & Guillaume St to study the activity of submarine canyons and fans near the city of Les Escou- mins, on the North Shore. Introduction Submarine canyons are initiated by failures on depositional oversteepenings of continental slopes

Long, Bernard

30

First record of the green microalgae Coccomyxa sp. in blue mussel Mytilus edulis (L.) from the Lower St. Lawrence Estuary (Québec, Canada).  

PubMed

During autumn 2012 and spring 2013, blue mussels Mytilus edulis (L.) with strongly deformed (L-shaped) posterior shell margins and green spots in soft tissue (microalgae) were collected from intertidal zone along the south shore of the Lower St. Lawrence Estuary near Rimouski (Québec, Canada). Identification of algal cells infesting mussels as Coccomyxa sp. was confirmed by rRNA sequencing and HPLC pigment analysis. Flow cytometric analysis revealed the presence of algal cells in the hemolymph and extrapallial fluid in mussels with deformed and non-deformed shells; concentrations of algal cells were ranged from about 200mL(-1) in mussels with actually non-deformed shells to concentrations reaching up to 3.8×10(7)mL(-1) in mussels with heavily deformed ones. Chemical analyses of soft tissues led us to conclude that butyltin compounds and trace metals cannot be considered among factors responsible for the shell deformity observed. Using scanning electron microscopy, the biogenic nature of the erosion on the external shell surface and aragonitic lenses of prisms in the curvature zone of deformed shells (in sections) were recorded. The sequence of the green algae from M. edulis of the Lower St. Lawrence Estuary was closely related to Coccomyxa sp. infecting M. edulis from the Flensburg Fjord (North Sea) and Modiolus modiolus (L.) from the Vityaz Bay (Sea of Japan). PMID:24837974

Zuykov, Michael; Belzile, Claude; Lemaire, Nicolas; Gosselin, Michel; Dufresne, France; Pelletier, Emilien

2014-07-01

31

Levels of C{sub 10}-C{sub 13} polychloro-n-alkanes in marine mammals from the Arctic and the St. Lawrence River estuary  

SciTech Connect

Marine mammals from various regions of the Arctic and the St. Lawrence River estuary were examined for the first time for levels of C{sub 10}--C{sub 13} polychloro-n-alkanes (sPCAs). Respective mean total sPCA concentrations in the blubber of beluga whales (Delphinapterus leucas) from Saqqaq and Nuussuaq, western Greenland, were 0.23 {+-} 0.02 (n = 2) and 0.164 {+-} 0.06 {micro}g/g (n = 2), similar to that in beluga from the Mackenzie Delta in the western Canadian Arctic 0.21 {+-} 0.08 {micro}g/g (m = 3). sPCAs levels were higher in beluga blubber from the St. Lawrence River (0.37 to 1.4 {micro}g/g). Mean sPCA concentrations in the blubber samples from walruses (Odobenus rosmarus) (Thule, northwest Greenland) and ringed seal (Phoca hispida) (Eureka, southwest Ellesmere Island) were 0.43 {+-} 0.06 (n = 2) and 0.53 {+-} 0.2 {micro}g/g (n = 6), respectively. Relative to commercial sPCA formulations, samples from the Arctic marine mammals showed a predominance of the shorter chain length lower percent chlorinated PCA congeners, the more volatile components of industrial formulations. This observation is consistent with long-range atmospheric transport of sPCAs to this region. The profiles of the belugas from the St. Lawrence River estuary, however, had higher proportions of the less volatile sPCA congeners, implying that contamination to this region is probably from local sources.

Tomy, G.T.; Muir, D.C.G.; Stern, G.A.; Westmore, J.B.

2000-05-01

32

Temporal and spatial variability of tidal-fluvial dynamics in the St. Lawrence fluvial estuary: An application of nonstationary tidal harmonic analysis  

NASA Astrophysics Data System (ADS)

tides in upstream reaches of rivers is a challenge, because tides are highly nonlinear and nonstationary, and accurate short-time predictions of river flow are hard to obtain. In the St. Lawrence fluvial estuary, tide forecasts are produced using a one-dimensional model (ONE-D), forced downstream with harmonic constituents, and upstream with daily discharges using 30 day flow forecasts from Lake Ontario and the Ottawa River. Although this operational forecast system serves its purpose of predicting water levels, information about nonstationary tidal-fluvial processes that can be gained from it is limited, particularly the temporal changes in mean water level and tidal properties (i.e., constituent amplitudes and phases), which are function of river flow and ocean tidal range. In this paper, a harmonic model adapted to nonstationary tides, NS_TIDE, was applied to the St. Lawrence fluvial estuary, where the time-varying external forcing is directly built into the tidal basis functions. Model coefficients from 13 analysis stations were spatially interpolated to allow tide predictions at arbitrary locations as well as to provide insights into the spatiotemporal evolution of tides. Model hindcasts showed substantial improvements compared to classical harmonic analyses at upstream stations. The model was further validated by comparison with ONE-D predictions at a total of 32 stations. The slightly lower accuracy obtained with NS_TIDE is compensated by model simplicity, efficiency, and capacity to represent stage and tidal variations in a very compact way and thus represents a new means for understanding tidal rivers.

Matte, Pascal; Secretan, Yves; Morin, Jean

2014-09-01

33

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

34

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

35

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

36

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

37

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

38

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 Available online xxxx Keywords: submarine mass movements morpho submarine geomorphology was revealed from multibeam bathymetry and seismic reflection surveys conducted

Long, Bernard

39

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

40

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

41

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

42

14C and 13C Contents of Dissolved Organic Matter in the St. Lawrence Estuary and in a Hydroelectric Reservoir From the Boreal Forest (Quebec)  

NASA Astrophysics Data System (ADS)

In this study we examine the 14C and 13C contents of Dissolved Organic Matter (DOM) in the St. Lawrence River, at its outlet near Quebec City, and in a large hydroelectric reservoir, from the Canadian Boreal forest (Robert-Bourassa reservoir) as a mean to document the origin and residence time of DOM in such large catchments. Samples of DOM were collected bi-weekly at the Quebec City station from November 2001 until November 2002, as part of a geochemical monitoring program of the river, carried out since 1997. At the Robert-Bourassa reservoir, sampling operations took place from July 15 to July 26, 2001. All samples were filtered and acidified on site, and preserved in brown glass bottles at 4° C. Prior to their isotopic analysis, DOM samples were freeze-dried. 13C analyses were made at GEOTOP whereas 14C measurements were performed at the Lawrence Livermore National Laboratory, for samples coming from the St. Lawrence River, and at the Laboratoire d'Hydrologie et de géochimie isotopique of University Paris XI for samples originating from the Robert-Bourassa reservoir. Results are expressed respectively in ‰ vs. V-PDB and in % of modern carbon (% MC; i.e. 13.56 dpm/g C in 1950, for d13C=-25 ‰ ). D13C values averaging -26.3 ± 0.2 ‰ in the St. Lawrence, and -27.1 ± 0.2 ‰ at the Robert-Bourassa reservoir, indicate that DOC originates from terrestrial production, although a slight influence of aquatic DOC is seen in the St. Lawrence river during low water level episodes. In the river, DOC-14C activities range from 97.7 to 106.7 ± 0.5 %, with a mean value of 103.9 ± 0.5 %, whereas samples from Robert-Bourassa reservoir show a range of values between 108.5 and 110.5 ± 0.9 %, with a mean of 109.5 ± 0.9 %. In comparison, measurements made during the late 80's, in a small brook of Ontario, yielded 14C-DOM activities ranging from 113 to 118 % MC (Schiff et al., 1990). Meanwhile, 14C-activity of atmospheric CO2 has decreased of approximately the same proportion. We conclude that soil-derived DOC represents the production of immediately preceding years, notably in the Boreal Forest reservoir, but that contribution of longer residence time DOC from the Great Lakes likely accounts for the slightly lower 14C-DOC values found in the St. Lawrence River. In conclusion, 14C and 13C contents indicate an overall short DOM residence time, thus that the primary production at its origin, and its degradation and transport in the drainage network are fast processes. Reference: Schiff, S. L., R. Aravena, S. E. Trumbore et P. J. Dillon. 1990. Dissolved organic carbon cycling in forested watersheds : a carbon isotope approach. Water Resources Research, 26, no 12, 2949-2957.

Lamontagne, J.; Hélie, J.; Hillaire-Marcel, C.

2004-05-01

43

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

44

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

45

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; Béland, P; Fournier, M

1995-01-01

46

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

47

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

48

Stocking young Atlantic salmon in St. Lawrence River system  

USGS Multimedia Gallery

Thousands of young Atlantic salmon are released into the St. Regis River system (a tributary of the St. Lawrence River) in an effort to restore this diminished Lake Ontario fish population. The salmon were reared at the USGS Tunison Laboratory in Cortland, N.Y., and are released by USGS scienti...

49

Two-dimensional hydrodynamic model of St. Lucie Estuary  

SciTech Connect

A two-dimensional hydrodynamic model of St. Lucie Estuary was developed to assess the impact of drainage canal discharge and storm water runoff. Water surface elevation, two-dimensional velocity field and salinity are collected during 1998--1998 ENSO episode. The data sets cover an eight months period that includes both wet ad dry weather conditions. The model has been applied to St. Lucie Estuary salinity study. It will also provide flow fields to a water quality model.

Hu, G.G.

1999-07-01

50

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

51

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

Code of Federal Regulations, 2014 CFR

...charges on the St. Lawrence River and Lake Ontario. 401...charges on the St. Lawrence River and Lake Ontario. Except...and assignments performed by U.S. registered pilots in the St. Lawrence River and Lake Ontario....

2014-10-01

52

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

Code of Federal Regulations, 2013 CFR

...charges on the St. Lawrence River and Lake Ontario. 401...charges on the St. Lawrence River and Lake Ontario. Except...and assignments performed by U.S. registered pilots in the St. Lawrence River and Lake Ontario....

2013-10-01

53

Mississippian conodonts, Lisburne Group, St. Lawrence Island, Alaska  

Microsoft Academic Search

Late Mississippian conodonts recovered from two sections of the Lisburne Group exposed along the Ongoveyuk River, western St. Lawrence Island, are few, poorly preserved, yet relatively diverse. At the West Fork and East Fork Ongoveyuk sections, the lower, dark-colored, cherty beds yield conodonts that belong in the upper part of Lane Faunal Unit 8. They are correlatives of the upper

P. F. Ressmeyer

1985-01-01

54

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

55

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

56

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

57

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

58

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

59

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

60

Holocene development of maritime ombrotrophic peatlands of the St. Lawrence North Shore in eastern Canada  

NASA Astrophysics Data System (ADS)

Macrofossil analyses were used to reconstruct long-term vegetation successions within ombrotrophic peatlands (bogs) from the northern shorelines of the St. Lawrence Estuary (Baie-Comeau) and the Gulf of St. Lawrence (Havre-St-Pierre). Over the Holocene, the timing and the ecological context of peatland inception were similar in both regions and were mainly influenced by fluctuations in relative sea level. Peat accumulation started over deltaic sands after the withdrawal of the Goldthwait Sea from 7500 cal yr BP and above silt-clay deposits left by the Laurentian marine transgression after 4200 cal yr BP. In each region, the early vegetation communities were similar within these two edaphic contexts where poor fens with Cyperaceae and eastern larch (Larix laricina) established after land emergence. The rapid transitions to ombrotrophy in the peatlands of Baie-Comeau are associated with particularly high rates of peat accumulation during the early developmental stage. The results suggest that climate was more propitious to Sphagnum growth after land emergence in the Baie-Comeau area. Macrofossil data show that treeless Sphagnum-dominated bogs have persisted over millennia and that fires had few impacts on the vegetation dynamics. This study provides insight into peatland vegetation responses to climate in a poorly documented region of northeastern America.

Magnan, Gabriel; Garneau, Michelle; Payette, Serge

2014-07-01

61

Invasion by stages in the St Louis River estuary  

EPA Science Inventory

The St. Louis River estuary is recognized as an invasive species “hotspot” - the harbor ranks among the top locations in the Great Lakes reporting the first occurrence of new, aquatic non-native species. To date, 18 non-native benthic invertebrate, 4 non-native crusta...

62

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

63

77 FR 38488 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...display will be held on the waters of the St. Lawrence...The Captain of the Port Buffalo has determined that fireworks...the Captain of the Port Buffalo has determined that a...zone will encompass all waters of the St. Lawrence...the Captain of the Port Buffalo or his designated...

2012-06-28

64

77 FR 30443 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...The Captain of the Port Buffalo has determined that fireworks...It would encompass all waters of St. Lawrence River...the Captain of the Port Buffalo or his on-scene representative...zone will encompass all waters of the St. Lawrence...the Captain of the Port Buffalo or his designated...

2012-05-23

65

Knowing, Mapping and Understanding st. Lawrence Biodiversity, with Special Emphasis on Bird Assemblages  

Microsoft Academic Search

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

Jean-Luc Desgranges; Benoît Jobin

2003-01-01

66

50 CFR Table 45 to Part 679 - St. Lawrence Island Habitat Conservation Area  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false St. Lawrence Island Habitat Conservation Area 45 Table 45 to Part 679 Wildlife and...679, Table 45 Table 45 to Part 679—St. Lawrence Island Habitat Conservation Area Longitude Latitude 16824.00W...

2011-10-01

67

50 CFR Table 45 to Part 679 - St. Lawrence Island Habitat Conservation Area  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false St. Lawrence Island Habitat Conservation Area 45 Table 45 to Part 679 Wildlife and...679, Table 45 Table 45 to Part 679—St. Lawrence Island Habitat Conservation Area Longitude Latitude 16824.00W...

2010-10-01

68

50 CFR Table 45 to Part 679 - St. Lawrence Island Habitat Conservation Area  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false St. Lawrence Island Habitat Conservation Area 45 Table 45 to Part 679 Wildlife and...679, Table 45 Table 45 to Part 679—St. Lawrence Island Habitat Conservation Area Longitude Latitude 16824.00W...

2013-10-01

69

50 CFR Table 45 to Part 679 - St. Lawrence Island Habitat Conservation Area  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false St. Lawrence Island Habitat Conservation Area 45 Table 45 to Part 679 Wildlife and...679, Table 45 Table 45 to Part 679—St. Lawrence Island Habitat Conservation Area Longitude Latitude 16824.00W...

2012-10-01

70

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

71

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

72

Mississippian conodonts, Lisburne Group, St. Lawrence Island, Alaska  

SciTech Connect

Late Mississippian conodonts recovered from two sections of the Lisburne Group exposed along the Ongoveyuk River, western St. Lawrence Island, are few, poorly preserved, yet relatively diverse. At the West Fork and East Fork Ongoveyuk sections, the lower, dark-colored, cherty beds yield conodonts that belong in the upper part of Lane Faunal Unit 8. They are correlatives of the upper St. Louis Formation in the Mississippi River Valley and, in northwest Alaska, are equivalent to the upper Nasorak and Kogruk Formations (Lisburne Group) along Nasorak Creek near Point Hope, and the Kogruk Formation at the Trail Creek, De Long Mountains, Misheguk Mountain quadrangle. The upper, light-colored, thicker-bedded interval at the West Fork exposure yields conodonts assignable to Lane Faunal unit 9 of latest Meramecian and earliest Chesterian age. This fauna occurs widely over North America in beds that correlate with the St. Genevieve Limestone in the Mississippi River Valley. On the Lisburne Peninsula, this interval correlates with at least a portion of the Kogruk Formation exposed at Niak Creek and Cape Lewis north of Point Hope. Conodont alteration indices (CAI) are very high and variable, ranging from 5.5 to 8.0, suggesting they resulted from contact rather than regional metamorphism.

Lane, H.R.; Ressmeyer, P.F.

1985-04-01

73

Influence of local variations in the ionic ratios on the density of seawater in the St. Lawrence area  

NASA Astrophysics Data System (ADS)

In order to verify the validity of the equations of state of seawater in their application to natural waters with low salinity, the chlorinity and conductivity of 144 samples from the St. Lawrence Gulf and Estuary and from the Saguenay Fjord were measured and used in several equations of state to calculate the density. These results were then compared with direct measurements with a densimeer on the same samples. The smallest deviations from the measured values were obtained with the equation of state of COX, CULKIN and RILEY, Deep-Sea Research, 14, 203-220 (1967), and COX, MCCARTNEY and CULKIN, Deep-Sea Research, 17, 679-689 (1970). The method of MILLEROin Marine Chemistry in the Coastal Environment, ACS Symposium, 18, 25-55 (1975) and Thalassia Jugoslavica, 14, 1-46 (1978), which uses the concept of "total salinity", could not be applied successfully to the waters in the St. Lawrence Estuary. A good agreement between measured and calculated values was obtained with the nine-component seawater model of POISSON, Thése de doctorat d'état ès-sciences physiques, Université Pierre et Marie Curie, Paris (1978).

Poisson, A.; Lebel, J.; Brunet, C.

1980-10-01

74

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.

75

Earthquakes and Geological Structures of the St. Lawrence Rift System  

NASA Astrophysics Data System (ADS)

The St. Lawrence Rift System (SLRS), which includes the Ottawa-Bonnechère and Saguenay grabens, is located well inside the North American plate. Most historic and the some 350 earthquakes recorded yearly occur in three main seismically active zones, namely Charlevoix (CSZ), Western Quebec (WQSZ), and Lower St. Lawrence (LSLSZ)). Outside these areas, most of the Canadian Shield and bordering regions have had a very low level of earthquake activity. In the SLRS, moderate to large earthquakes (Moment magnitude (M) 5.5 to M 7) are known to have occurred since 1663 causing landslides and damage mostly to unreinforced masonry elements of buildings located on ground capable of amplifying ground motions. Most earthquakes in these seismic zones share common characteristics such as mid- to upper crustal focal depths, no known surface ruptures and proximity to SLRS faults. Variations also exist such as vast seismically-active region (WQSZ and LSLSZ), presence of a large water body (CSZ and LSLSZ), and absence of SLRS faults near concentration of earthquakes (WQSZ). The CSZ is the best studied seismic zone and there, earthquakes occur in the Canadian Shield, mostly in a 30 X 85 km rectangle elongated along the trend of the St. Lawrence River with local variations in focal depth distribution. Faults related to the SLRS and to a meteor impact structure exist and earthquakes occur along the SLRS faults as well as in between these faults. Overall, the SLRS faults are probably reactivated by the larger earthquakes (M ? 4.5) of the 20th century (CSZ in 1925; WQCSZ in 1935 and 1944; Saguenay in 1988) for which we have focal mechanisms. We propose that caution be exercised when linking historical events that have uncertain epicentres with SLRS faults. Similarly, SLRS faults should not be necessarily considered to be the reactivated structures for most small to moderate earthquakes (M < 4.5). A good example of this is the earthquakes of the WQSZ that tend to concentrate in a well-defined NW-SE alignment with no obvious geological control, except perhaps, a hypothetical hotspot track. Two local factors can lead to the occurrence of SLRS earthquakes: weak faults or enhanced stress levels. We propose that local conditions, concentrated in a few seismic zones, can alter these factors and lead to the occurrence of earthquakes, especially those with M < 4.5. At a continent-wide scale, the correlation between the SLRS and earthquakes is appealing. We suggest, however, that pre-existing faults related to the SLRS do not explain all features of the seismicity. Seismicity is concentrated in more active areas, some with conspicuous normal faults and some with suspected weakening mechanisms such as intense pre-fracturing (e.g. due to a meteorite impact), the passage over a hot spot, or the presence of intrusions and lateral crustal density variations.

Lamontagne, M.; Ranalli, G.

2013-12-01

76

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

77

Origin of particulate organic carbon in the upper St. Lawrence: isotopic constraints  

NASA Astrophysics Data System (ADS)

Seven sampling locations in the upper St. Lawrence River near the city of Cornwall (Ontario, Canada), including the main river and six near-shore ecosystems (a creek, embayments and a wetland) were studied in order to determine the origin of particulate organic carbon. Parameters studied included chlorophyll-a (chl-a), particulate organic carbon (POC) and dissolved inorganic carbon (DIC), as well as the isotopic compositions of the latter two (? 13C POC, ? 13C DIC). The results show that in situ photosynthesis and detrital inputs are both significant contributors to the POC pool in the isolated embayments. The former dominates during warm seasons, with POC concentrations up to 2663 ?g/l and chl-a concentrations up to 26.1 ?g/l. Near-shore ecosystems have a wide range of ? 13C POC values (-31.5 to -16.3‰), but this variability is not reflected in the `Main Channel'. There, the ? 13C POC signal is uniformly close to -27‰, in accord with estimates from earlier studies on the river's estuary. This suggests that the POC contribution from near-shore ecosystems is minor. Although the `Main Channel' has low chl-a concentrations, model calculations suggest that most of its POC originates from photosynthetic activity, probably within the Great Lakes.

Barth, Johannes A. C.; Veizer, Ján; Mayer, Bernhard

1998-10-01

78

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

79

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

80

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 ...

81

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 interactions between climate and society, so that informed regional adaptation strategies can be developed; this is the adaptation component. Communication of climate change information to various publics

82

Cultural Encounters at St. Lawrence University. Final FIPSE Report.  

ERIC Educational Resources Information Center

This final report of a three-year project at Saint Lawrence University (NY), entitled the Cultural Encounters Project, details a faculty and curriculum development project that focused on particular issues in global or international studies. The project grew out of the so-called "cultural wars," or clash between those who sought to retain an…

Stoddard, Eve W.

83

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

84

78 FR 40260 - International Joint Commission: Public Comment on a Proposal for Lake Ontario and St. Lawrence...  

Federal Register 2010, 2011, 2012, 2013, 2014

...to comment on a proposal for managing the water levels and flows in Lake Ontario and the St. Lawrence River that...and Massena, New York. The management of water flows influences water levels on Lake Ontario and in the St Lawrence River...

2013-07-03

85

Estimating the mercury exposure dose in a population of migratory bird hunters in the St. Lawrence River region, Québec, Canada  

Microsoft Academic Search

St. Lawrence River hunters (Québec, Canada) are exposed to the pollutants, especially mercury, that contaminate birds and fish. However, the health risks of this have remained unclear because of a lack of information about the hunters’ duck, geese, and sportfish consumption habits. A nutritional survey was set up to characterize waterfowl and sportfish consumption in St. Lawrence River duck hunters

Jean-François Duchesne; Denis Gauvin; Birgit Braune; Suzanne Gingras; Éric Dewailly

2004-01-01

86

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

... Northern Bering Sea Research Area and St. Lawrence Island Habitat Conservation Area 17 Figure 17 to part 679 Wildlife and...Northern Bering Sea Research Area and St. Lawrence Island Habitat Conservation Area ER25JY08.011 [73 FR 43371,...

2010-10-01

87

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

88

Constraints on Lake Agassiz discharge through the late-glacial Champlain Sea (St. Lawrence Lowlands, Canada) using salinity proxies and an estuarine circulation model  

USGS Publications Warehouse

During the last deglaciation, abrupt freshwater discharge events from proglacial lakes in North America, such as glacial Lake Agassiz, are believed to have drained into the North Atlantic Ocean, causing large shifts in climate by weakening the formation of North Atlantic Deep Water and decreasing ocean heat transport to high northern latitudes. These discharges were caused by changes in lake drainage outlets, but the duration, magnitude and routing of discharge events, factors which govern the climatic response to freshwater forcing, are poorly known. Abrupt discharges, called floods, are typically assumed to last months to a year, whereas more gradual discharges, called routing events, occur over centuries. Here we use estuarine modeling to evaluate freshwater discharge from Lake Agassiz and other North American proglacial lakes into the North Atlantic Ocean through the St. Lawrence estuary around 11.5 ka BP, the onset of the Preboreal oscillation (PBO). Faunal and isotopic proxy data from the Champlain Sea, a semi-isolated, marine-brackish water body that occupied the St. Lawrence and Champlain Valleys from 13 to 9 ka, indicate salinity fell about 7-8 (range of 4-11) around 11.5 ka. Model results suggest that minimum (1600 km3) and maximum (9500 km3) estimates of plausible flood volumes determined from Lake Agassiz paleoshorelines would produce the proxy-reconstructed salinity decrease if the floods lasted <1 day to 5 months and 1 month to 2 years, respectively. In addition, Champlain Sea salinity responds very quickly to the initiation (within days) and cessation (within weeks) of flooding events. These results support the hypothesis that a glacial lake flood, rather than a sustained routing event, discharged through the St. Lawrence Estuary during the PBO. ?? 2011 Elsevier Ltd.

Katz, B.; Najjar, R.G.; Cronin, T.; Rayburn, J.; Mann, M.E.

2011-01-01

89

The Oligochaeta (Annelida, Clitellata) of the St. Lawrence Great Lakes region: An update  

USGS Publications Warehouse

An updated oligochaete species list for the Great Lakes region is provided. The list was developed through the reexamination of the taxa reported in a previous report in 1980, addition of new taxa or records collected from the region since 1980, and an update of taxonomy commensurate with systematic and nomenclatural changes over the intervening years since the last review. The authors found 74 papers mentioning Great Lakes oligochaete species. The majority of these papers were published in the 1980s. The literature review and additional collections resulted in 15 species being added to the previous list. Nine taxa were removed from the previous list due to misidentification, synonymies, level of identification, or inability to confirm the identity. Based on this review, 101 species of Oligochaeta are now known from the St. Lawrence Great Lakes watershed. Of these, 95 species are known from the St. Lawrence Great Lakes proper, with an additional 6 species recorded from the inland waters of the watershed. The greatest diversity of oligochaete species was found in the inland waters of the region (81) followed by Lake Huron (72), Lake Ontario (65), Lake Erie (64), Lake Superior (63), Lake Michigan (62), St. Marys River (60), Niagara River (49), Saginaw Bay (44), St. Clair River (37), Lake St. Clair (36), St. Lawrence River (27), and the Detroit River (21). Three species are suspected of being introduced, Branchiura sowerbyi, Gianius aquaedulcis, and Ripistes parasita, and two are believed to be endemic, Thalassodrilus hallae and Teneridrilus flexus.

Spencer, Douglas R.; Hudson, Patrick L.

2003-01-01

90

Aerial surveys of cetaceans in the Gulf of St. Lawrence in 1995 and 1996  

Microsoft Academic Search

Aerial line-transect surveys of cetaceans were flown in the Gulf of St. Lawrence in late August and early September of 1995 and in late July and early August of 1996. Systematic north-south transects were spaced 15' of longitude apart. In 1995, the study area comprised the entire Gulf, divided into three strata for analysis; 69% was flown. In 1996, a

M. C. S. Kingsley; R. R. Reeves

1998-01-01

91

Goals and Objectives for Computing in the Associated Colleges of the St. Lawrence Valley.  

ERIC Educational Resources Information Center

A forecast of the computing requirements of the Associated Colleges of the St. Lawrence Valley, an analysis of their needs, and specifications for a joint computer system are presented. Problems encountered included the lack of resources and computer sophistication at the member schools and a dearth of experience with long-term computer consortium…

Grupe, Fritz H.

92

Associated Colleges of the St. Lawrence Valley. Summary Report: 1974-75.  

ERIC Educational Resources Information Center

The Associated Colleges of the St. Lawrence Valley were chartered by the Board of Regents of the University of the State of New York to facilitate and stimulate cooperative relationships among four distinctive institutions of higher education to enable them to improve their ability to achieve their chosen goals without a loss of their unique…

Associated Colleges of the St. Lawrence Valley, Potsdam, NY.

93

Reptiles and Amphibians: Shy and Sensitive Vertebrates of the Great Lakes Basin and St. Lawrence River  

Microsoft Academic Search

Bioaccumulation of environmental contaminants has been documented in amphibians and reptiles inhabiting the Great Lakes, St. Lawrence River and elsewhere. The effects of pollutants on the physiology and reproduction of amphibians and reptiles has also been reported but this research has largely been restricted to laboratory studies. Much less work has been conducted to quantify the effects of toxic chemical

Christine A. Bishop; Andrée D. Gendron

1998-01-01

94

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.S.Fish and Wildlife Service, and centroids reported in Herdendorf and Hartley (1980). All data correspond to aerial

McMaster University

95

The St. Lawrence polynya and the Bering shelf circulation: New observations and a model comparison  

Microsoft Academic Search

Using 14 yearlong instrumented moorings deployed south of St. Lawrence Island, along with oceanographic drifters, we investigate the circulation over the central Bering shelf and the role of polynyas in forming and disseminating saline waters over the shelf. We focus also on evaluating the Gawarkiewicz and Chapman (1995) model of eddy production within coastal polynyas. Principal results include the following.

S. Danielson; K. Aagaard; T. Weingartner; S. Martin; P. Winsor; G. Gawarkiewicz; D. Quadfasel

2006-01-01

96

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

97

Physical factors affecting the relative abundance of native and invasive amphipods in the St. Lawrence River  

Microsoft Academic Search

The Ponto-Caspian amphipod Echinogammarus ischnus (Stebbing, 1899) is reportedly replacing the North American amphipod Gammarus fasciatus Say, 1818, in the lower Great Lakes, but the two species appear to coexist in the upper St. Lawrence River several years after invasion by E. ischnus. A multi-site survey in the river between Lake Ontario and Montreal (Quebec) found that E. ischnus and

M. E. Palmer; A. Ricciardi

2004-01-01

98

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 ...

99

Distribution of submerged aquatic vegetation in the St. Louis River estuary: Maps and models  

EPA Science Inventory

In late summer of 2011 and 2012 we used echo-sounding gear to map the distribution of submerged aquatic vegetation (SAV) in the St. Louis River Estuary (SLRE). From these data we produced maps of SAV distribution and we created logistic models to predict the probability of occurr...

100

ANNOTATED BIBLIOGRAPHY OF ENVIRONMENTAL RESEARCH CONDUCTED WITHIN THE ST. LOUIS RIVER ESTUARY 1903-1982  

EPA Science Inventory

This annotated bibliography reviews manuscripts and publications for content, not for results. It is thus intended as a tool for individuals attempting to locate specific types of studies conducted within the St. Louis River estuary. Each review includes the study dates, specific...

101

Contaminant exposure in Montrealers of Asian origin fishing the St. Lawrence River: Exploratory assessment  

SciTech Connect

Fishing and fish consumption are widely practiced among members of certain ethnocultural groups. Information assessment led them to ascribe high levels of consumption of locally caught sportfish to Montrealers of Asian origin and to hypothesize that their choices of species and fish organs differ from those of the majority group. An exploratory assessment of contaminant bioindicators reflective of St. Lawrence river fish consumption was conducted in late 1995 among nine Vietnamese and nine Bangladeshi Montreal sportfishers identified by community contacts. Vietnamese participants, six men and three women, were 27--70 years of age and had immigrated to Canada 3--20 years earlier. In contrast, the nine Bangladeshi males aged 28--41 years had been in Canada for 2--13 years. Bioindicator concentrations among Bangladeshi and Vietnamese participants are compared to those found for majority-community Montreal-area high-level consumers recruited on the St. Lawrence River during winter 1995.

Kosatsky, T. [Montreal Public Health Program, Quebec (Canada)] [Montreal Public Health Program, Quebec (Canada); [McGill Univ., Montreal, Quebec (Canada). Dept. of Occupational Health; [Quebec Toxicology Center, Montreal, Quebec (Canada); Przybysz, R.; Shatenstein, B. [Montreal Public Health Program, Quebec (Canada)] [Montreal Public Health Program, Quebec (Canada); [McGill Univ., Montreal, Quebec (Canada). Dept. of Occupational Health; Weber, J.P. [Quebec Toxicology Center, Montreal, Quebec (Canada)] [Quebec Toxicology Center, Montreal, Quebec (Canada); Armstrong, B. [London School of Hygiene (United Kingdom)] [London School of Hygiene (United Kingdom)

1999-02-01

102

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

103

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

104

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

105

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

106

Patterns in invertebrate and periphyton size distributions from navigation buoys in the St. Lawrence River  

Microsoft Academic Search

For the purposes of conducting environmental assessments, it has been suggested that benthic size distributions could serve\\u000a as complementary or alternative measures to traditional taxonomic descriptions, which are labour intensive and require much\\u000a expertise. Consequently, temporal patterns of invertebrate and algal size distributions, along a trophic gradient from St.\\u000a Lawrence River navigational buoys, were investigated in this study. It was

Vincent Mercier; Chantal Vis; Antoine Morin; Christiane Hudon

1999-01-01

107

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

108

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

109

Ice ridging and ice drift in southern Gulf of St Lawrence, Canada, during winter storms  

Microsoft Academic Search

During February and March 2004, satellite-tracked ice beacons and helicopter-borne sensors collected ice-drift and ice-thickness data from the southern Gulf of St Lawrence, Canada, to study the region's ice-thickness evolution and ice-drift behavior in response to winter storms. Three northeasterly storms passed through the area during the observation period, pushing the pack ice against the north shore of Prince Edward

S. J. Prinsenberg; A. van der Baaren; I. K. Peterson

2006-01-01

110

Comparison of Electromagnetic Sea Ice Thickness Measurements with RADARSAT Imagery in the Gulf of St Lawrence  

Microsoft Academic Search

Ice-plus-snow thickness profiles collected using a helicopter-borne electromagnetic sensor (Ice Probe) in the Gulf of St. Lawrence in early March 1996 are used to validate SAR signatures of ice observed in RADARSAT imagery. The ice thickness and RADARSAT data were co-registered using SLAR imagery and satellite-tracked ice beacons deployed on drifting ice floes. The ice thickness measurements obtained with the

I. K. Peterson; S. J. Prinsenberg; J. S. Holladay

111

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

112

Research management in the Great Lakes and St. Lawrence River basins: Challenges and opportunities  

SciTech Connect

Research management in the Great Lakes and St. Lawrence River basins is both challenging and filled with opportunities. From the perspective of public health practice, research management is more than just research managers managing discrete programs; it requires everyone involved in the process to become active participants, including researchers, communities,l potential interest groups, policymakers, and other stakeholders. Agencies, organizations, and individuals responsible for managing research and resources in the Great Lakes and St. Lawrence River basins are facing problems of decreased research funding, data gaps, and research quality. Managers of research and resources in the basins face many challenges as they address these problems. They are challenged with strengthening the link between research and management in the face of decreasing resources and increasing expectations of results and findings while extending those results and findings to public health practice. A number of actions and activities have been proposed that can lead to better management of constrained programs, pooled resources, partnerships, targeted priorities, and improved effectiveness. With guidance and assistance from the International Joint Commission (IJHC), research managers in the Great Lakes and St. Lawrence River basins who have initiated and maintained traditional research programs based on sound science are now adopting different and innovative management strategies.

Rosa, C.T. de; Rosemond, Z.A.; Cibulas, W. [Dept. of Health and Human Services, Atlanta, GA (United States). Agency for Toxic Substances and Disease Registry] [Dept. of Health and Human Services, Atlanta, GA (United States). Agency for Toxic Substances and Disease Registry; Gilman, A.P. [Health Canada, Ottawa, Ontario (Canada). Environmental Health Directorate] [Health Canada, Ottawa, Ontario (Canada). Environmental Health Directorate

1999-04-01

113

Freshwater mussels as biomonitors for organic industrial contaminants and pesticides in the St. Lawrence River.  

PubMed

Native mussels (Elliptio complanata and Lampsilis radiata radiata) were collected from 17 stations in the St. Lawrence River between Lake Ontario and Trois Rivières and from three stations in a major tributary, the Ottawa River, in October, 1985. Mussels were solvent-extracted and analyzed individually by dual capillary column gas chromatography for seven organochlorine pesticides, 11 chlorobenzenes, octachlorostyrene and 63 PCB congeners. Bioconcentration patterns for contaminants in mussel tissues implicated Lake Ontario as the source of Mirex and DDT derivatives to the system and the Grass River as the major source of PCBs. Numbers of PCB congeners in mussels increased from 21-27 in the upper river to 56-59 in the Cornwall/Massena industrial core, mainly due to the appearance of di-, tri- and tetrachlorobiphenyls; an average of 43 congeners persisted as far downstream as Lac Saint-Pierre. Concentrations of most contaminants in mussels from the Ottawa River were 50-75% lower than the lowest values reported for the St. Lawrence River. This study provides information on the origin, bioavailability and persistence of organic contaminants in the St. Lawrence River ecosystem. PMID:2128132

Metcalfe, J L; Charlton, M N

1990-11-01

114

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

115

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

116

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

117

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

118

Genetics and shell morphometrics of assimineids (Mollusca, Caenogastropoda, Truncatelloidea) in the St Lucia Estuary, South Africa  

PubMed Central

Abstract The Assimineidae are a family of amphibious microgastropods that can be mostly found in estuaries and mangroves in South Africa. These snails often occur in great numbers and are ecologically important to the St Lucia Estuary, which forms a crucial part of the iSimangaliso Wetland Park, a UNESCO World Heritage Site. Genetic and shell morphometric analyses were conducted on individuals collected from nine localities distributed from the northern lake regions to the southern lake and the mouth of the St Lucia estuarine lake. Mitochondrial (COI) and nuclear (28S) DNA was used to construct Bayesian Inference, Neighbour-joining, Maximum Parsimony and Maximum Likelihood trees. Principal Component Analysis and Cluster Analysis were performed on standard shell parameter data. Results indicate that two different taxa are present in St Lucia. The taxon comprising individuals from the South Lake and St Lucia Estuary Mouth is identified as Assiminea cf. capensis Bartsch, in accordance with the latest taxonomic consensus. The taxon comprising assimineid individuals from False Bay, North Lake and South Lake, is here tentatively named “Assiminea” aff. capensis (Sowerby). These two taxa exhibit patterns of spatial overlap that appear to vary depending on environmental parameters, particularly salinity. The need to resolve the complex taxonomy of assimineids is highlighted. PMID:25061361

Miranda, Nelson A. F.; van Rooyen, Ryan; MacDonald, Angus; Ponder, Winston; Perissinotto, Renzo

2014-01-01

119

Mapping ecosystem services in the St. Louis River estuary (presentation)  

EPA Science Inventory

Management of ecosystems for sustainable provision 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 EPA goal of community sust...

120

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 ...

121

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

NASA Astrophysics Data System (ADS)

St. Lawrence Island Yupik hunters on St. Lawrence Island, Alaska, take hundreds of Pacific walrus (Odobenus rosmarus divergens) each year. The harvest and associated effort (hunting trips taken), however, are variable from year to year and also from day to day, influenced by physical environmental factors among other variables. We used data from 1996 to 2010 to construct generalized additive models (GAMs) to examine several relationships among the variables. Physical factors explained 18% of the variability in harvest in Savoonga and 25% of the variability in effort; the corresponding figures for Gambell were 24% and 32%. Effort alone explained 63% of the harvest in Savoonga and 59% in Gambell. Physical factors played a relatively smaller role in determining hunting efficiency (walrus taken per hunting trip), explaining 15% of the variability in efficiency in Savoonga and 22% in Gambell, suggesting that physical factors play a larger role in determining whether to hunt than in the outcome of the hunt once undertaken. Combining physical factors with effort explained 70% of the harvest variability in Savoonga and 66% in Gambell. Although these results indicate that other factors (e.g. fuel prices, socioeconomic conditions) collectively cause a greater share of variability in harvest and effort than ice and wind, at least as indicated by the measures used as predictors in the GAMs, they also suggest that environmental change is also likely to influence future harvest levels, and that climate models that yield appropriately scaled data on ice and wind around St. Lawrence Island may be of use in determining the magnitude and direction of those influences.

Huntington, Henry P.; Noongwook, George; Bond, Nicholas A.; Benter, Bradley; Snyder, Jonathan A.; Zhang, Jinlun

2013-10-01

122

Impacts of environmental changes on the hydrology and sedimentary processes at the confluence of St. Lawrence tributaries: potential effects on fluvial ecosystems  

Microsoft Academic Search

This study examines the effects of changes in St. Lawrence water levels and in hydrological regimes of two tributaries of\\u000a the St. Lawrence, the Richelieu and Saint-François Rivers, on the sedimentary dynamics of their confluence in an historical\\u000a context and in response to projected climate changes. Analysis of historical data indicates that alteration to St. Lawrence\\u000a mean water levels and

Claudine Boyer; Patrick M. Verhaar; André G. Roy; Pascale M. Biron; Jean Morin

2010-01-01

123

Organochlorine and metal contaminants in traditional foods from St. Lawrence Island, Alaska.  

PubMed

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 PCBs, three chlorinated pesticides, and seven heavy metals (mercury, copper, zinc, arsenic, selenium, cadmium, and lead). Concentrations of PCB in rendered oils (193-421 ppb) and blubber (73-317 ppb) from all marine mammal samples were at levels that trigger advisories for severely restricted consumption, using U.S. Environmental Protection Agency (EPA) fish consumption advisories. Concentrations of pesticides were lower, but were still elevated. The highest PCB concentrations were found in polar bear (445 ppb) and the lowest in reindeer adipose tissue (2 ppb). Marine mammal and polar bear meat in general have PCB concentrations that were 1-5% of those in rendered oils or adipose tissue. PCB concentrations in organs were higher than meat. Concentrations of metals in oils and meats from all species were relatively low, but increased levels of mercury, cadmium, copper, and zinc were present in some liver and kidney samples. Mercury and arsenic were found in lipid-rich samples, indicating organometals. These results show that the source of the elevated concentrations of these contaminants in the Yupik population is primarily from consumption of marine mammal blubber and rendered oils. PMID:21797772

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

2011-01-01

124

Middle pleistocene mollusks from St. Lawrence Island and their significance for the paleo-oceanography of the Bering Sea  

USGS Publications Warehouse

Drift, evidently of Illinoian age, was deposited on St. Lawrence Island at the margin of an ice cap that covered the highlands of the Chukotka Peninsula of Siberia and spread far eastward on the continental shelf of northern Bering Sea. Underlying the drift on the northwestward part of the island are mollusk-bearing beds deposited during the Kotzebuan Transgression. A comparison of mollusk faunas from St. Lawrence Island, Chukotka Peninsula, and Kotzebue Sound suggests that the present northward flow through Bering and Anadyr Straits was reversed during the Kotzebuan Transgression. Cold arctic water penetrated southward and southwestward bringing an arctic fauna to the Gulf of Anadyr. Warmer Pacific water probably entered eastern Bering Sea, passed eastward and northeastward around eastern and northern St. Lawrence Island, and then became entrained in the southward currents that passed through Anadyr Strait. ?? 1972.

Hopkins, D.M.; Rowland, R.W.; Patton, W.W., Jr.

1972-01-01

125

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

126

33 CFR 207.610 - St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater. 207.610...207.610 St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater....

2013-07-01

127

33 CFR 207.610 - St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor...  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater. 207.610...207.610 St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater....

2012-07-01

128

33 CFR 207.610 - St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor...  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater. 207.610...207.610 St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater....

2014-07-01

129

33 CFR 207.610 - St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor...  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater. 207.610...207.610 St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater....

2011-07-01

130

33 CFR 207.610 - St. Lawrence River, Cape Vincent Harbor, N.Y.; use, administration, and navigation of the harbor...  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater. 207.610...207.610 St. Lawrence River, Cape Vincent Harbor...navigation of the harbor and U.S. breakwater....

2010-07-01

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

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

133

Sediment salt-load in the St Lucia Estuary during the severe drought of 2002 2006  

NASA Astrophysics Data System (ADS)

The purpose of this study was to determine whether there was a sufficiently high residual salt load in the dry sediments of the St Lucia Estuary to cause salinity problems should it later fill up with either freshwater or seawater. The estuary lakes have suffered the effects of a severe drought since 2002 with the result that many areas were dry, and the salinity of the residual water varied between 4 psu and up to five times that of seawater. Measurements of the salts content in the sediments to a depth of 20 cm showed that more than 2 million tonnes of salt was held in this layer of the sediment in 2006. Recent management of the estuary (since 1970) has ensured that the mouth was not artificially opened. This was to prevent the inflow of seawater, with its salts, that would otherwise enter while the drought was in place. The results of the sediment salinity data showed that if the drought had been broken and the lake area filled with rain and river water, the resulting salinity would be about 6 psu. In March 2007, Cyclone Gamede in the Indian Ocean off the east coast of South Africa produced a wave climate at sea that resulted in the mouth breaching; thus introducing an estimated 12 million tonnes of salts. The high salinity in the system resulting from this breach is expected to have an adverse effect on the ecology of the system, whereas the residual salinity in the sediments would not have caused an environmental problem. If the estuary and lake system were to fill completely with seawater, the residual salts together with seawater will raise the salinity to an initial value higher than 40 psu, which will have the effect of suppressing much of the important submerged vegetation that is vital for sustaining juvenile fish in the system. Many of the large fauna will also suffer from a shortage of freshwater.

Bate, G. C.; Taylor, R. H.

2008-09-01

134

Effects of salinity and temperature on ex situ germination of the threatened Gulf of St. Lawrence Aster,  

E-print Network

Effects of salinity and temperature on ex situ germination of the threatened Gulf of St. Lawrence of salinity (0­20 g/L) and temperature (16­30°C) on germination of S. laurentianum seeds over 32 days. The time-course of germination was significantly affected by both salinity and temperature. At lower

Heard, Stephen B.

135

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

Microsoft Academic Search

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

Colin G. Rousseaux; A. Branchaud; Philip A. Spear

1995-01-01

136

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

137

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

138

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

139

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

140

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

141

Shipping noise in whale habitat: Characteristics, sources, budget, and impact on belugas in SaguenaySt. Lawrence  

E-print Network

of anthropogenic noise on marine life is a worldwide concern that has been the object of several reviews recently). Such a broad band covers the hearing sensitivity and communication bands of several marine organisms in Saguenay­St. Lawrence Marine Park hub Ce´dric Gervaise GIPSA-Lab, Dept. Image-Signal, 11 rue des Mathe

Paris-Sud XI, Université de

142

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

Microsoft Academic Search

The levels of DNA adducts in the hepatic tissue of the white sucker fish speciesCatostomus commersoni were determined by32P-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

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

1995-01-01

143

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...

144

Vertical distribution and water solubility of phosphorus and heavy metals in sediments of the St. Lucie Estuary, South Florida, USA  

Microsoft Academic Search

Accumulation and distribution of heavy metals and phosphorus in sediments impact water quality. There has been an increasing concern regarding fish health in the St. Lucie Estuary, which is related to increased inputs of nutrients and metals in recent decades. To investigate vertical changes of contaminants (P, Cd, Cr, Co, Cu, Ni, Pb, Zn, and Mn) in sediments of the

Z. L. He; M. Zhang; P. J. Stoffella; X. E. Yang

2006-01-01

145

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

146

Mo & Fe Influences on Nitrate Assimilation in Lake Ontario and the St Lawrence River  

NASA Astrophysics Data System (ADS)

Lake Ontario has undergone a steady increase in nitrate since the early 1970s, a phenomenon also occurring in other large lakes. Possible causes of this increase include rising urban and agricultural runoff, atmospheric deposition, less demand for N due to effective point source P control, and trace metal-N co-limitation as observed in Lake Erie. Despite the abundance of nitrate in Lake Ontario, heterocystous cyanobacteria have been detected here setting up the paradoxical situation wherein some cyanobacteria are investing in the more costly diazotrophy whilst surrounded by a form of N that requires less energy and metal quota to assimilate. Mo and Fe are involved in reductive nitrate assimilation making it possible that reductive nitrate assimilation in Lake Ontario is limited in phytoplankton by low trace metal bioavailability. To test this hypothesis, 1-d enrcihment experiments were conducted using trace metal clean techniques in June 2013 at two coastal sites in Lake Ontario, and 4-d enrichment experiments were conducted in July 2013 on main channel waters of the St. Lawrence River, the outflow of Lake Ontario. Water was sampled from the metalimnion of Lake Ontario and from surface water of the main channel of the river. Water was enriched with the the following treatments in triplicate: control, 100 nM KH2PO4, 50 nM FeCl3, 50 nM Na2MoO4, and a mix of P, Fe & Mo. Experiments in the river showed significant effects due to P (increase in Chl-a, NO3 and SiO2 drawdown, changes in phytoplankton community, increase in photosynthetic efficiency [Fv/Fm]) but less impact of trace metals relative to control, presumably due to greater ambient trace metal bioavailability. As measured using FluoroProbe, the phytoplankton community changed very little (over 1 d) in lake waters; there was no significant change in total chl-a. However, as in the river, Fv/Fm revealed significant metal and P effects with the P, Fe & Mo mix being significantly greater than control (Fig. 1; we will present data relating to the response of PON and POC pools to the enrichment experiments). The results suggest that P was limiting phytoplankton growth and that Mo and Fe were more co-limiting in the lake than in the river. This information builds on prior work demonstrating Fe/N co-limitation and is the first study to investigate the role of Mo in the N cycle in the Laurentian Great Lakes. Figure 1. Photosynthetic efficiency in experimental treatments measured using fast repetition rate fluorimetry after 1 d (Lake Ontario) and 4 d (St. Lawrence River); * = P < 0.05.

Twiss, M. R.; Salk, K.; Avolio, L. N.; Chappaz, A.; Ostrom, N. E.

2013-12-01

147

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

148

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

149

Ebullition rates and mercury concentrations in St. Lawrence river sediments and a benthic invertebrate.  

PubMed

Ebullition, the release of gas from anaerobic decomposition in sediments, was recorded in a mercury-contaminated depositional zone (Zone 1) of the St. Lawrence River Area of Concern in Cornwall, Ontario, Canada. The aim of the present study was to test if this disturbance affected the bioavailability of total mercury (THg) and methylmercury (MeHg) in surficial sediments to a benthic invertebrate (Echinogammarus ischnus). Ebullition rates ranged from <1 to 2,800?ml/m(2) daily, with methane gas comprising 29 to 84% of the total. No direct effects of ebullition were found on either abiotic (sediment or pore water THg or MeHg concentrations) or biotic (amphipod THg or MeHg concentrations) variables measured. Instead, amphipod MeHg concentrations were best predicted by pore water THg and MeHg concentrations, organic matter of surficial sediments, and water depth and location. Trend surface analyses demonstrated that a shallow, southwestern part of Zone 1 was most contaminated with pore water mercury, which decreased in a gradient toward the northeast. Further study is needed to determine if the amount of sediment resuspended by ebullition affects the spatial distribution of mercury. PMID:23296404

Razavi, N Roxanna; Ridal, Jeffrey J; de Wit, William; Hickey, M Brian C; Campbell, Linda M; Hodson, Peter V

2013-04-01

150

The presence, characteristics and earthquake implications of the St. Lawrence fault zone within and near Lake Ontario (Canada USA)  

NASA Astrophysics Data System (ADS)

Questions persist concerning the earthquake potential of the populous and industrial Lake Ontario (Canada-USA) area. Pertinent to those questions is whether the major fault zone that extends along the St. Lawrence River valley, herein named the St. Lawrence fault zone, continues upstream along the St. Lawrence River valley at least as far as Lake Ontario or terminates near Cornwall (Ontario, Canada)-Massena (NY, USA). New geological studies uncovered paleotectonic bedrock faults that are parallel to, and lie within, the projection of that northeast-oriented fault zone between Cornwall and northeastern Lake Ontario, suggesting that the fault zone continues into Lake Ontario. The aforementioned bedrock faults range from meters to tens of kilometers in length and display kinematically incompatible displacements, implying that the fault zone was periodically reactivated in the study area. Beneath Lake Ontario the Hamilton-Presqu'ile fault lines up with the St. Lawrence fault zone and projects to the southwest where it coincides with the Dundas Valley (Ontario, Canada). The Dundas Valley extends landward from beneath the western end of the lake and is marked by a vertical stratigraphic displacement across its width. The alignment of the Hamilton-Presqu'ile fault with the St. Lawrence fault zone strongly suggests that the latter crosses the entire length of Lake Ontario and continues along the Dundas Valley. The Rochester Basin, an east-northeast-trending linear trough in the southeastern corner of Lake Ontario, lies along the southern part of the St. Lawrence fault zone. Submarine dives in May 1997 revealed inclined layers of glaciolacustrine clay along two different scarps within the basin. The inclined layers strike parallel to the long dimension of the basin, and dip about 20° to the north-northwest suggesting that they are the result of rigid-body rotation consequent upon post-glacial faulting. Those post-glacial faults are growth faults as demonstrated by the consistently greater thickness, unit-by-unit, of unconsolidated sediments on the downthrown (northwest) side of the faults relative to their counterparts on the upthrown (southeast) side. Underneath the western part of Lake Ontario is a monoclinal warp that displaces the glacial and post-glacial sediments, and the underlying bedrock-sediment interface. Because of the post-glacial growth faults and the monoclinal warp the St. Lawrence fault zone is inferred to be tectonically active beneath Lake Ontario. Furthermore, within the lake it crosses at least five major faults and fault zones and coexists with other neotectonic structures. Those attributes, combined with the large earthquakes associated with the St. Lawrence fault zone well to the northeast of Lake Ontario, suggest that the seismic risk in the area surrounding and including Lake Ontario is likely much greater than previously believed.

Wallach, J. L.

2002-08-01

151

Recent sediments of the St. Marks River coast, northwest Florida, a low-energy, sediment-starved estuary  

SciTech Connect

The St. Marks river of northwest Florida drains parts of the central panhandle of northwestern Florida, and a small area in southwestern Georgia. It traverses nearly 56.3 kilometers through a watershed of 1,711 square kilometers. The slow-moving river carries little sediment and terminates in Apalachee Bay, a low-energy embayment in the northeasternmost Gulf of Mexico. The coastal region is characterized by mudflats, seagrass beds, and an absence of sandy beaches and barrier islands. Clastic sediments of the coast and shelf rest on a shallow-dipping carbonate platform. The upper surface of the platform is locally karstic. As a result, like other rivers in this region of northwest Florida, the St. Marks watershed is marked by sinkholes and disappearing streams. The fact that the river travels underground through part of its lower watershed serves to trap or sieve some of its clastic load. In the estuary, the undulating karst topography causes the estuarine sediments to vary in thickness from 0 to 4+ meters. The concave shape of the coastline and its orientation with respect to prevailing winds result in low average wave energy. Sedimentation is therefore controlled by riverine and tidal forces. The relatively low energy conditions result in good preservation of the sedimentary record in the St. Marks estuary. A suite of sediment cores has been collected in the lower river, estuary and adjacent Gulf of Mexico. Lead-210 dating results indicate a slow average sedimentation rate ([approximately] 1mm/yr). Investigation of sedimentation rates and sediment characteristics over time in the St. Marks estuary indicate that sedimentologic conditions in this low-energy environment have been relatively stable during the recent geologic history of the estuary.

Highly, A.B. (Florida State Univ., Tallahassee (United States). Dept. of Geology Florida Geological Survey, Tallahassee, FL (United States)); Donoghue, J.F. (Florida State Univ., Tallahassee, FL (United States). Dept. of Geology); Garrett, C.; Hoenstine, R.W.; Hertler, H. (Florida Geological Survey, Tallahassee, FL (United States))

1994-03-01

152

Biomarkers in zebra mussels ( Dreissena polymorpha) for the assessment and monitoring of water quality of the St Lawrence River (Canada)  

Microsoft Academic Search

Five biomarkers (MT: metallothionein-like proteins, EROD: ethoxyresorufin ortho-dééthylase, DNA strand breaks, LPO: peroxidation of lipids, VG: vitellogenin-like protiens) were measured in the soft tissues of zebra mussels (Dreissena polymorpha) in order to assess the spatial variation of exposure to contaminants along the St Lawrence River (Canada). Fifteen mussels >25 mm shell length were analyzed from each of the 13 sampling

Yves de Lafontaine; François Gagné; Christian Blaise; Georges Costan; Pierre Gagnon; H. M. Chan

2000-01-01

153

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

154

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

155

Organotins in zebra mussels (Dreissena polymorpha) and sediments of the Quebec City Harbour area of the St. Lawrence River.  

PubMed

Toxic antifouling agents such as tributyltin (TBT) and triphenyltin (TPT) have been released in aquatic ecosystems through the use of antifouling paint applied to ship hulls, pleasure crafts and fish nets and these compounds can bioaccumulate in aquatic organisms. The purpose of this study was 1) to assess the extent of the distribution of organotins from a contaminated marina to the St. Lawrence River system by measuring organotin concentrations in zebra mussels (Dreissena polymorpha) and in sediments collected from 9 sites along the St. Lawrence River near Quebec City in July 1998, and 2) to examine the histopathological condition of zebra mussel tissues from these sites. TBT concentrations in zebra mussels were between 37 and 1078 ng Sn g(-1) wet weight, with the highest value found in the Bassin Louise marina. Elevated concentrations were also found in two other marinas. The concentrations decreased sharply to background levels just outside the marinas. All butyltins were detected in all sediments analysed, with highest values found in the Bassin Louise marina. Phenyltins were detected in three of the nine sites in low concentrations (<55 ng Sn g(-1)) in zebra mussels. There was a significant correlation between TBT in sediments and mussels. Gonadal development of zebra mussels varied largely between sites, and was negatively associated to TBT levels in mussel tissue. This study shows that TBT contamination remains a problem in localised freshwater sectors of the St. Lawrence River. PMID:11311388

Regoli, L; Chan, H M; de Lafontaine, Y; Mikaelian, I

2001-07-01

156

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

157

Characterization of turbidity in Florida's Lake Okeechobee and Caloosahatchee and St. Lucie estuaries using MODIS-Aqua measurements.  

PubMed

This paper describes the use of ocean color remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Aqua satellite to characterize turbidity in Lake Okeechobee and its primary drainage basins, the Caloosahatchee and St. Lucie estuaries from 2002 to 2010. Drainage modification and agricultural development in southern Florida transport sediments and nutrients from watershed agricultural areas to Lake Okeechobee. As a result of development around Lake Okeechobee and the estuaries that are connected to Lake Okeechobee, estuarine conditions have also been adversely impacted, resulting in salinity and nutrient fluctuations. The measurement of water turbidity in lacustrine and estuarine ecosystems allows researchers to understand important factors such as light limitation and the potential release of nutrients from re-suspended sediments. Based on a strong correlation between water turbidity and normalized water-leaving radiance at the near-infrared (NIR) band (nL(w)(869)), a new satellite water turbidity algorithm has been developed for Lake Okeechobee. This study has shown important applications with satellite-measured nL(w)(869) data for water quality monitoring and measurements for turbid inland lakes. MODIS-Aqua-measured water property data are derived using the shortwave infrared (SWIR)-based atmospheric correction algorithm in order to remotely obtain synoptic turbidity data in Lake Okeechobee and normalized water-leaving radiance using the red band (nL(w)(645)) in the Caloosahatchee and St. Lucie estuaries. We found varied, but distinct seasonal, spatial, and event driven turbidity trends in Lake Okeechobee and the Caloosahatchee and St. Lucie estuary regions. Wind waves and hurricanes have the largest influence on turbidity trends in Lake Okeechobee, while tides, currents, wind waves, and hurricanes influence the Caloosahatchee and St. Lucie estuarine areas. PMID:22858282

Wang, Menghua; Nim, Carl J; Son, Seunghyun; Shi, Wei

2012-10-15

158

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

159

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

160

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.

U.S. Geological Survey

1951-01-01

161

Aquatic Vegetation of the St. Louis River Estuary: Initial Analysis of Point-intercept Data Collected in 2010 for Restoration Modeling.  

EPA Science Inventory

A new effort to model aquatic vegetation patterns in the St. Louis River Estuary was initiated in summer of 2010 for the purpose of informing wetland restoration planning in the St. Louis River Area of Concern (AOC) at 40th Avenue West in Duluth. Aquatic vascular plants were doc...

162

14C chronology for ice retreat and inception of Champlain Sea in the St. Lawrence Lowlands, Canada  

NASA Astrophysics Data System (ADS)

AMS radiocarbon cross-dating of plant debris and marine shells trapped in a lake basin on Mount St. Hilaire (Québec, Canada) provides a direct assessment of a reservoir effect totaling ca. 1800 14C years during the early stage of Champlain Sea. Pollen-based extrapolation of bottommost ages on terrestrial plant macrofossils in sediments of this lake, and of another lake nearby support an estimate of 11,100 ± 100 14C yr B.P. for marine invasion in the Central St. Lawrence River Lowlands. Results indicate a 400-1000 years younger regional chronology of ice retreat, now congruent with the one inferred from the New England varve chronology. This is a summary of a longer paper to be published in French.

Richard, Pierre J. H.; Occhietti, Serge

2005-05-01

163

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

164

Reconnaissance investigation of high-calcium marble in the Beaver Creek area, St. Lawrence County, New York  

USGS Publications Warehouse

Three belts of marble of the Grenville Series were mapped in the Beaver Creek drainage basin, St. Lawrence County, N.Y. One of these, on the west side of Beaver Creek, consists of coarsely crystalline pure calcitic marble that occurs in a zone at least 10 by 0.8 km in extent. Samples of marble show CaCO3 content to be greater than 93 percent, and some samples contain greater than 96 percent, and only small amounts of MgO and Fe203 are present. Marble in two other belts to the east of Beaver Creek are variable in composition, but locally have high content of calcium carbonate material. The marble deposit west of Beaver Creek has a chemical composition favorable for specialized chemical, industrial, and metallurgical uses. Another favorable aspect of the deposit is its proximity to inexpensive water transportation on the St. Lawrence Seaway only 27.5 km away by road, at Ogdensburg, N.Y.

Brown, C. Ervin

1978-01-01

165

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

166

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

167

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

168

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

169

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

170

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

171

Distribution of submerged aquatic vegetation in the St. Louis River estuary: Maps and models (Presentation)  

EPA Science Inventory

SAV provides the biophysical basis for several ecosystem services in Great Lakes estuaries including rearing and adult habitat for commercially and recreationally important fishes, foraging habit for waterfowl, and nutrient retention. Understanding sources of variation in SAV in ...

172

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

173

Among and within-species variability in fatty acid signatures of marine fish and invertebrates on the Scotian Shelf, Georges Bank, and southern Gulf of St. Lawrence  

Microsoft Academic Search

The fat and fatty acid compositions of 28 species of fish and invertebrates ( n = 954) from the Scotian Shelf, Georges Bank, and the Gulf of St. Lawrence were determined. Discriminant analysis of the 16 most numerous species (n ? 18 each), using 17 major fatty acids, classified species with greater than 98% accuracy and grouped species into three

Suzanne M. Budge; Sara J. Iverson; W. Don Bowen; Robert G. Ackman

2002-01-01

174

Estimation of Emissions of ?-Hexachlorcyclohexane from the Great Lakes–St. Lawrence Ecosystem Using a Coupled Efficient Kalman Filter–Atmospheric Transport–Soil Model  

Microsoft Academic Search

An efficient linear Kalman filter has been combined with a coupled atmospheric transport and soil–air exchange model to determine organochlorine pesticides emissions on the regional scale. In this study, results of ?-HCH emissions from the Great Lakes–St. Lawrence ecosystem, estimated from the coupled model, are presented and discussed. A source receptor technique is used to identify a priori the locations

Jiainmin Ma; Yi-fan Li; Laurier Poissant

2003-01-01

175

Temporal variation of blood and hair mercury levels in pregnancy in relation to fish consumption history in a population living along the St. Lawrence River  

Microsoft Academic Search

Fish consumption from the Great Lakes and the St. Lawrence River has been decreasing over the last years due to advisories and increased awareness of the presence of several contaminants. Methylmercury (MeHg), a well-established neurotoxicant even at low levels of exposure, bioaccumulates to differing degrees in various fish species and can have serious adverse effects on the development and functioning

Joëlle Morrissette; Larissa Takser; Genevieve St-Amour; Audrey Smargiassi; Julie Lafond; Donna Mergler

2004-01-01

176

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

177

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

178

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

179

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

180

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

181

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

182

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

183

Biochemical indicators of contaminant exposure in birds and turtles of the Great Lakes-St. Lawrence River  

SciTech Connect

Pre-fledgling chicks of tree swallows, double-crested cormorants, herring gulls, common terns and hatchling snapping turtles were collected from contaminated Areas of Concern and reference sites in the Great Lakes and St. Lawrence River to determine the geographic and species variation in biomarker responses. EROD activity in colonial waterbirds was generally an order of magnitude above EROD activity in tree swallows and snapping turtles. Notably, EROD activity in colonial waterbirds did not correlate with organochlorine contamination in livers at one industrialized site suggesting that exposure to other contaminants, possibly PAHs, may be an important factor. Retinol concentrations in cormorants were non-detectable and retinyl palmitate concentrations were equal or greater than those in herring gulls. In tree swallows, there was a significant negative correlation between vitamin A concentration in liver and kidney and EROD activity. In snapping turtles, there was a significant induction in EROD activity and significantly higher cytochrome P450 IAI level in livers from the Great Lakes site relative to a clean inland location. There were no significant differences in porphyrin concentrations between sites.

Bishop, C. [Canadian Wildlife Service, Burlington, Ontario (Canada); Trudeau, S.; Kennedy, S.; Norstrom, R. [National Wildlife Research Centre, Hull, Quebec (Canada); Stegeman, J. [Woods Hole Oceanographic Institution, MA (United States)

1995-12-31

184

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

185

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

186

Biomarkers in zebra mussels (Dreissena polymorpha) for the assessment and monitoring of water quality of the St Lawrence River (Canada).  

PubMed

Five biomarkers (MT: metallothionein-like proteins, EROD: ethoxyresorufin ortho-dééthylase, DNA strand breaks, LPO: peroxidation of lipids, VG: vitellogenin-like protiens) were measured in the soft tissues of zebra mussels (Dreissena polymorpha) in order to assess the spatial variation of exposure to contaminants along the St Lawrence River (Canada). Fifteen mussels >25 mm shell length were analyzed from each of the 13 sampling sites. Significant differences between sites were noted for all biomarkers, but the general level of variability was low. Three biomarkers (DNA, LPO and VG) exhibited a similar pattern of spatial variation while MT and EROD had distinct and specific patterns. MT had the strongest discriminating power and EROD showed the largest range of variation among sites. Highest biomarker responses were measured in specimens from local contaminated sites such as harbors and industrial sectors. A positive relationship was found between MT and copper (Cu), but no significant correlation was observed between other biomarker responses and the levels of ten trace metals bioaccumulating in the zebra mussels tissues. Results indicate that the measurement of biomarker responses is technically feasible. The performance of each biomarker is assessed in the context of the role and advantages of selecting a battery of biomarkers for detecting contamination problems. The use of zebra mussels as a sentinel species for biomonitoring potential toxic effects in situ is discussed. PMID:10930650

de Lafontaine Y; Gagné; Blaise; Costan; Gagnon; Chan

2000-08-01

187

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

PubMed

: The potential use of retinoids and ?-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 ?-carotene and the retinoids in heron egg yolks by reversed-phase HPLC. When results were expressed either as the molar ratio of retinol: retinyl palmitate or as retinyl palmitate concentration, significant differences were found between colonies; however, retinyl palmitate concentration was deemed the better biomarker because it was not significantly influenced by embryonic stage of development. Retinyl palmitate concentrations in freshwater colonies were negatively related to PCB congeners Nos 105 and 118 as well as their TCDD-EQ values (p < 0.02, r (2)=0.78). Egg tetrachloro-mono-ortho biphenyl concentrations were also negatively related to retinyl palmitate (p < 0.005, r (2)=0.90). With the exception of the two mono-ortho co-planar congeners detected in the present study, the contamination levels found in heron eggs were well below those found for other bird species in the Great Lakes area and, so far, no detrimental effects have been reported in Great Blue Heron populations in Quebec. These results suggest that retinyl palmitate may be useful as a sensitive and non-invasive biomarker for monitoring organochlorine contaminant effects in the Great Blue Heron in freshwater sites. PMID:24202125

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

1994-12-01

188

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

189

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

190

Mercury transport between sediments and the overlying water of the St. Lawrence River area of concern near Cornwall, Ontario.  

PubMed

Contaminated sediments in the St. Lawrence River remain a difficult problem despite decreases in emissions. Here, sediment and pore water phases were analyzed for total mercury (THg) and methyl mercury (MeHg) and diffusion from the sediment to the overlying water was 17.5 + or - 10.6 SE ng cm(-2) yr(-1) for THg and 3.8 + or - 1.7 SE ng cm(-2) yr(-1) for MeHg. These fluxes were very small when compared to the particle-bound mercury flux accumulating in the sediment (183 + or - 30 SE ng cm(-2) yr(-1)). Studies have reported that fish from the westernmost site have higher Hg concentrations than fish collected from the other two sites of the Cornwall Area of Concern, which could not be explained by differences in the Hg flux or THg concentrations in sediments, but the highest concentrations of sediment MeHg, and the greatest proportions of MeHg to THg in both sediment and pore water were observed where fish had highest MeHg concentrations. PMID:20092919

Delongchamp, Tania M; Ridal, Jeffrey J; Lean, David R S; Poissant, Laurier; Blais, Jules M

2010-05-01

191

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

192

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

193

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

194

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

195

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

196

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

197

Distribution changes of Atlantic cod (Gadus morhuaL.) in the northern Gulf of St Lawrence in relation to an oceanic cooling  

Microsoft Academic Search

Research vessel trawl survey data were examined to investigate age-by-age changes in the distribution of Atlantic cod (Gadus morhua L.) with respect to depth, temperature, and latitude in the northern Gulf of St Lawrence (Canada) in both winter (1978-1994) and summer (1984-1995) in relation to a water cooling event. We used a cumulative distribution function method that statistically compares distributions

M. Castonguay; C. Rollet; A. Frechet; P. Gagnon; D. Gilbert; J.-C. Brethes

1999-01-01

198

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

199

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

200

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

201

(222)Rn activity in groundwater of the St. Lawrence Lowlands, Quebec, eastern Canada: relation with local geology and health hazard.  

PubMed

One hundred ninety-eight groundwater wells were sampled to measure the (222)Rn activity in the region between Montreal and Quebec City, eastern Canada. The aim of this study was to relate the spatial distribution of (222)Rn activity to the geology and the hydrogeology of the study area and to estimate the potential health risks associated with (222)Rn in the most populated area of the Province of Quebec. Most of the groundwater samples show low (222)Rn activities with a median value of 8.6 Bq/L. Ninety percent of samples show (222)Rn activity lower than 100 Bq/L, the exposure limit in groundwater recommended by the World Health Organization. A few higher (222)Rn activities (up to 310 Bq/L) have been measured in wells from the Appalachian Mountains and from the magmatic intrusion of Mont-Saint-Hilaire, known for its high level of indoor radon. The spatial distribution of (222)Rn activity seems to be related mainly to lithology differences between U-richer metasediments of the Appalachian Mountains and magmatic intrusions and the carbonaceous silty shales of the St. Lawrence Platform. Radon is slightly enriched in sodium-chlorine waters that evolved at contact with clay-rich formations. (226)Ra, the parent element of (222)Rn could be easily adsorbed on clays, creating a favorable environment for the production and release of (222)Rn into groundwater. The contribution of groundwater radon to indoor radon or by ingestion is minimal except for specific areas near Mont-Saint-Hilaire or in the Appalachian Mountains where this contribution could reach 45% of the total radioactive annual dose. PMID:24973780

Pinti, Daniele L; Retailleau, Sophie; Barnetche, Diogo; Moreira, Floriane; Moritz, Anja M; Larocque, Marie; Gélinas, Yves; Lefebvre, René; Hélie, Jean-François; Valadez, Arisai

2014-10-01

202

Novel flame retardants in urban-feeding ring-billed gulls from the St. Lawrence River, Canada.  

PubMed

This study investigated the occurrence of a comprehensive suite of polybrominated diphenyl ethers (PBDEs) and current-use flame retardants (FRs) in ring-billed gulls breeding in a highly industrialized section of the St. Lawrence River, downstream from Montreal (QC, Canada). Despite major point-sources and diffuse contamination by FRs, nearly no FR data have been reported in birds from this area. Bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (BEHTBP) was detected in 89% of ring-billed gull livers (mean: 2.16 ng/g ww; max: 17.6 ng/g ww). To our knowledge, this is the highest detection frequency and highest concentrations reported thus far in any avian species or populations. Dechlorane Plus (DP) isomers were also particularly abundant (anti-DP detected in 100% and syn-DP in 93% of livers). Other detected FR compounds (3-14% detection) included 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB), hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) and ?-1,2-dibromo-4-(1.2-dibromoethyl)-cyclohexane (?-TBECH). Mean BDE-209 (57.2 ± 12.2 ng/g ww) in ring-billed gull livers was unexpectedly high for this midtrophic gull species, exceeding levels reported in several apex raptors such as peregrine falcons. BDE-209's relative contribution to ?PBDEs was on average 25% (exceeding BDE-47 and BDE-99) and contrasted with profiles typically reported for fish-eating gull species. The present study highlighted preoccupying gaps in upcoming FR regulations and stressed the need for further investigation of the sources of FR exposure in highly urbanized areas. PMID:22845168

Gentes, Marie-Line; Letcher, Robert J; Caron-Beaudoin, Elyse; Verreault, Jonathan

2012-09-01

203

Biogeochemical factors influencing net mercury methylation in contaminated freshwater sediments from the St. Lawrence River in Cornwall, Ontario, Canada.  

PubMed

The activity of various anaerobic microbes, including sulfate reducers (SRB), iron reducers (FeRP) and methanogens (MPA) has been linked to mercury methylation in aquatic systems, although the relative importance of each microbial group in the overall process is poorly understood in natural sediments. The present study focused on the biogeochemical factors (i.e. the relative importance of various groups of anaerobic microbes (FeRP, SRB, and MPA) that affect net monomethylmercury (MMHg) formation in contaminated sediments of the St. Lawrence River (SRL) near Cornwall (Zone 1), Ontario, Canada. Methylation and demethylation potentials were measured separately by using isotope-enriched mercury species ((200)Hg(2+) and MM(199)Hg(+)) in sediment microcosms treated with specific microbial inhibitors. Sediments were sampled and incubated in the dark at room temperature in an anaerobic chamber for 96h. The potential methylation rate constants (K(m)) and demethylation rates (K(d)) were found to differ significantly between microcosms. The MPA-inhibited microcosm had the highest potential methylation rate constant (0.016d(-1)), whereas the two SRB-inhibited microcosms had comparable potential methylation rate constants (0.003d(-1) and 0.002d(-1), respectively). The inhibition of methanogens stimulated net methylation by inhibiting demethylationand by stimulating methylation along with SRB activity. The inhibition of both methanogens and SRB was found to enhance the iron reduction rates but did not completely stop MMHg production. The strong positive correlation between K(m) and Sulfate Reduction Rates (SRR) and between K(d) and Methane Production Rates (MPR) supports the involvement of SRB in Hg methylation and MPA in MMHg demethylation in the sediments. In contrast, the strong negative correlation between K(d) and Iron Reduction Rates (FeRR) shows that the increase in FeRR corresponds to a decrease in demethylation, indicating that iron reduction may influence net methylation in the SLR sediments by decreasing demethylation rather than favouring methylation. PMID:21176945

Avramescu, Mary-Luyza; Yumvihoze, Emmanuel; Hintelmann, Holger; Ridal, Jeff; Fortin, Danielle; Lean, David R S

2011-02-01

204

Contaminant residues in snapping turtle (Chelydra s. serpentina) eggs from the Great Lakes-St. Lawrence River basin (1999 to 2000).  

PubMed

To determine temporal and geographic variations of environmentally persistent pollutants, the concentrations of several contaminants were measured in snapping turtle eggs in 1999 and 2000. Contaminants included polychlorinated biphenyls (PCBs), non- ortho PCBs, polychlorinated dibenzodioxins and furans, organochlorine pesticides, and total mercury. Egg collection sites within the St. Lawrence Area of Concern (AOC) and the Territory of Akwesasne included Turtle Creek, Snye Marsh, and Raquette River. Additional contaminated sites were Gray's Creek (within the St. Lawrence AOC boundary), Coote's Paradise (Hamilton Harbour AOC), and the Territory of Walpole Island (St. Clair AOC). Reference sites were Lake Sasajewun, Algonquin Provincial Park in central Ontario, and in close proximity to the St. Lawrence Area AOC, Hoasic Creek and Cooper Marsh. Eggs from clutches collected from Akwesasne contained the highest concentrations of contaminants. Mean total PCB concentrations for Akwesasne clutches ranged from 1,900 to 61,000 ng/g wet weight (w.w.), which was 360 to 3,100 times higher than the mean concentrations at the reference sites. The high levels of contaminants in eggs, from sites within Akwesasne, were consistent with trends reported in the past and reflect the influence of the proximity of heavy industry. Current contaminant concentrations in clutches from Coote's Paradise are comparable with those recorded in 1989 and 1990 but are 200 to 800 times lower than concentrations reported in 1984 and 1988. Eggs from Lake Sasajewun contained relatively low contaminant levels, which is consistent with atmospheric deposition. Our results support that snapping turtles are good indicators of temporal and geographic contaminant trends. PMID:15386150

Ashpole, S L; Bishop, C A; Brooks, R J

2004-08-01

205

The contribution of various types of settling particles to the flux of organic carbon in the Gulf of St. Lawrence  

NASA Astrophysics Data System (ADS)

The contents of 31 samples from free-drifting sediment traps deployed in the Gulf of St. Lawrence (GSL) were analyzed for the individual contribution of the different types of particles encountered to the total particulate organic carbon (POC) flux. Two trap models were used in 1993-1994: small traps at 50 m depth and large traps at 50 and 150 m. Total POC fluxes averaged 42 mg C m -2 d -1 for the more reliable large trap and 149 mg C m -2 d -1 for the small trap. The POC fluxes were attributed to different classes of particles based upon microscopically determined particle dimensions and carbon/volume algorithms available in the literature. Fecal pellets, followed by phytoplankton, were the major attributable components, with important contributions by microzooplankton, particularly during the summer of 1994. The mean fluxes for pellets (6 and 60 mg C m -2 d -1, for the large and small traps, respectively) and phytoplankton (3.2 and 42.9 mg C m -2 d -1) were in the range of those encountered in other areas of moderate primary productivity. Mean zooplankton carbon fluxes (1.8 and 8.5 mg C m -2 d -1, respectively), however, reflect higher than average zooplankton abundances in the GSL. The C fluxes of specific algal groups confirmed the existence of three trophic regimes previously identified from water column studies and numeric cell fluxes: (1) a period when diatoms were dominant during the spring, (2) a longer interval, which was dominated by dinoflagellates at most others times of the year, and (3) a period of transition during summer. Carbon of animal origin dominated the attributable flux, including an important fraction associated with heterotrophic dinoflagellates. The contribution of marine snow to the total flux (estimated as the difference between the total POC flux and the sum of the attributed components) frequently amounted to more than 60%. The true importance of marine snow remains uncertain, however, because the errors associated with each of the measured components accumulate to produce large uncertainties. The methodological problems involved are discussed.

Romero-Ibarra, Nancy; Silverberg, Norman

2011-10-01

206

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

207

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

208

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

209

Temporal trends and spatial variability of mercury in four fish species in the Ontario segment of the St. Lawrence River, Canada.  

PubMed

The Massena (New York) and Cornwall (Ontario) region has a long history of Hg discharge into the St. Lawrence River. The objectives of this study were to evaluate if Hg levels have declined in this portion of the river since 1975 and to compare Hg level in fish species upstream and downstream of this area in order to evaluate the anthropogenic contribution to Hg levels in fish. Mercury levels in four fish species were monitored over a 20-year period (1975-1995). A general linear model and an analysis of covariance were used to extract temporal trends and spatial variability, respectively, while correcting the data for fish length. Over time, Hg levels declined in most fish species. In the four regions studied, Hg levels in fish were similar, which suggests that other sources like atmospheric deposition and Hg loading from the Great Lakes may also contribute to the Hg burden in fish in the St. Lawrence River. This indicates that fish, with large home range, are good biomonitors of temporal Hg releases but their ability to avoid point sources makes them less appealing as biomonitors to address spatial variability in Hg releases. PMID:18040593

Goulet, Richard R; Lalonde, J D; Chapleau, F; Findlay, S C; Lean, D R S

2008-05-01

210

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

211

Continuous analysis of dissolved gaseous mercury and mercury volatilization in the upper St. Lawrence River: exploring temporal relationships and UV attenuation.  

PubMed

The formation and volatilization of dissolved gaseous mercury (DGM) is an important mechanism by which freshwaters may naturally reduce their mercury burden. Continuous analysis of surface water for diurnal trends in DGM concentration (ranging from 0 to 60.4 pg L(-1); n=613), mercury volatilization (ranging from 0.2 to 1.1 ng m(-2) h(-1); n=584), and a suite of physical and chemical measurements were performed during a 68 h period in the St. Lawrence River near Cornwall (Ontario, Canada) to examine the temporal relationships governing mercury volatilization. No lag-time was observed between net radiation and OGM concentrations (highest cross-correlation of 0.817), thus supporting previous research indicating faster photoreduction kinetics in rivers as compared to lakes. A significant lag-time (55-145 min; maximum correlation = 0.625) was observed between DGM formation and mercury volatilization, which is similar to surface water Eddy diffusion times of 42-132 min previously measured in the St. Lawrence River. A depth-integrated DGM model was developed using the diffuse integrated vertical attenuation coefficients for UVA and UVB (K(dI UVA) = 1.45 m(-1) K(dI UVB)= 3.20 m(-1)) Low attenuation of solar radiation was attributed to low concentrations of dissolved organic carbon (mean = 2.58 mg L(-1) and particulate organic carbon (mean = 0.58 mg L(-1) in the St. Lawrence River. The depth-integrated DGM model developed found that the top 0.3 m of the water column accounted for only 26% of the total depth-integrated DGM. A comparison with volatilization data indicated that a large portion (76% or 10.5 ng m(-2) of the maximum depth-integrated DGM (13.8 ng m(-2))is volatilized over a 24 h period. Therefore, at least 50% of all DGM volatilized was produced at depths below 0.3 m. These results highlight the importance of solar attenuation in regulating DGM formation with depth. The results also demonstrate both the fast formation of DGM in rivers and the importance of understanding DGM dynamics with depth as opposed to surface waters. PMID:17822100

O'Driscoll, N J; Poissant, L; Canário, L; Ridal, J; Lean, D R S

2007-08-01

212

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

213

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

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Cancer.gov

St. Joseph Hospital, Orange, California St. Joseph Hospital Cancer Center 1100 West Stewart Drive Orange CA 92863-5600 www.sjo.org • Larry Ainsworth, President and CEO, St. Joseph Hospital • James Padova, MD, Cancer Program Medical Director

215

Temporal and seasonal variation in acetylcholinesterase activity and glutathione-S-transferase in amphipods collected in mats of Lyngbya wollei in the St-Lawrence River (Canada).  

PubMed

Mats of filamentous algae Lyngbya wollei cover large areas on top of the sediments along the St-Lawrence River. Like most cyanobacteria, L. wollei produce toxins, named lyngbyatoxin (LYNGTX), an analog of saxitoxin. In order to verify the neurotoxic potential of these filamentous cyanobacteria, we collected amphipods within local vegetation at three sites in summer months: a site rich in L. wollei (Lake St-Louis [LSL]) and two urban sites composed of macrophytes but devoid of L. wollei mats (Richelieu River [RICH] and L'Assomption River [ASSO] outlets). The body weight of each amphipod was measured, and the neurotoxicity was estimated with the measurement of acetylcholinesterase (AChE) and glutathione-s-transferase (GST) activities. Levels of protein-bound phosphates were also evaluated, to rule out contamination by Microcystis sp. The results showed that the activity of acetylcholinesterase measured in amphipods in ASSO and RICH was lower than the activity found in amphipods collected in L. wollei mats in LSL. In addition, amphipods found in L. wollei mats at the LSL site have significantly higher GST activity than those located at the two devoid sites, RICH and ASSO. No significant change was observed for protein-bound phosphate levels. This study suggests that the presence of L. wollei triggers potential toxicity. PMID:23702304

Gélinas, Malorie; Lajeunesse, André; Gagnon, Christian; Gagné, François

2013-08-01

216

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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

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

218

Residual toxicity of two insecticides on three field populations of Lygus lineolaris (Hemiptera: Miridae) collected along the St Lawrence valley in eastern Canada.  

PubMed

Insecticides are still the single main pest control method employed today by most growers to mitigate damage done by the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae). In eastern Canada, the complex agricultural ecosystem, which may be described as a mosaic of farmlands dispersed among natural habitats (forest, prairies), allows tarnished plant bug adults to fly and move from sprayed to non-sprayed areas. In 2004 (late August to early September), three populations of L. lineolaris were collected from three mixed vegetation strips adjacent to orchards and vineyards along the St Lawrence valley: the Niagara Peninsula (Ontario), Dunham (Quebec) and La Pocatière (Quebec). Assays were done in the laboratory by confining adults in glass vials coated with dried residues. The estimated LC(50) values for the three populations varied from 11.2 to 16.8 x 10(-5) g L(-1) for azinphos-methyl and from 0.8 to 1.4 x 10(-5) g L(-1) for cypermethrin. In contrast to the Mississippi delta, no tolerance to insecticides was found in the populations collected. Possible explanations for this non-tolerance to insecticides includes a very low selection pressure as a result of the reduced number of insecticide treatments done in the context of the diversified agricultural landscapes encountered in eastern Canada which allow movements of adults from treated to non-treated areas. PMID:17387716

Fleury, Dominique; Bostanian, Noubar J; Mauffette, Yves; Vincent, Charles

2007-05-01

219

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

220

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

221

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

222

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Cancer.gov

St. Joseph’s/Candler, Savannah, Georgia Nancy N. and J.C. Lewis Cancer & Research Pavilion 5353 Reynolds Street Savannah, GA 31405 www.sjchs.org • Paul P. Hinchey, President and CEO, St. Joseph’s/Candler • Morris Geffen, MD, Principal Investigator/NCCCP

223

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

224

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

225

Environmental contamination and human exposure assessment to manganese in the St-Lawrence River ecozone (Quebec, Canada) using an environmental fate/exposure model: GEOTOX.  

PubMed

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 model: GEOTOX. The results of our MMT research program on abiotic and biotic components of the ecosystem and on the human exposure were used to validate the model estimations. Air and surface soil were selected as source terms with an annual Mn input rate in each compartment of 0.083-0.113 mol km-2 d-1 and 0.44-0.87 mol km-2 d-1 respectively (Mn3O4 equivalent). The predicted air, soil, plant, surface water and sediment concentrations were similar (+/- 50%) to values measured in the Montreal region. As expected, the ingestion pathway was the main absorption route for adults (> 99%), with vegetables and fruits contributing almost 80% of the dietary intake of Mn. The multimedia exposure doses for adult men predicted by the model ranged between 0.04 and 0.08 mg kg-1 d-1 compared to 0.004 and 0.201 mg kg-1 d-1 (average = 0.05) for workers from the MMT study. Considering the landscape configuration and the source vectors (air and soil) included in the model, GEOTOX estimations were in good agreement with measured values. PMID:9241868

Loranger, S; Zayed, J

1997-01-01

226

Sediment mercury dynamics and historical trends of mercury deposition in the St. Lawrence River area of concern near Cornwall, Ontario, Canada.  

PubMed

The St. Lawrence River near Cornwall, Ontario was designated an Area of Concern by the International Joint Commission in 1985. Sediments from this area have historically been contaminated with mercury (Hg), and although concentrations have decreased since the 1970s, they still remain high. Nine sediment cores were collected from three sites within the Area of Concern in 2004/05 to determine the variability in historical profiles of Hg deposition to the river. Sediment and pore water phases were analyzed for total mercury (THg) and methyl mercury (MeHg) and cores were analyzed for 210Pb to determine chronologies of sedimentation at these sites. Mercury diffusion rates in pore waters within the sediment column were determined to be very low (between 0 and 2.15 ng cm(-2) year(-1), n = 3) compared to the recent Hg sedimentation rates at these sites (183+/- 30 ng cm(-2) year(-1) SE, n = 9) determined by multiplying surface Hg concentrations with 210Pb-derived sedimentation rates. These results indicate that Hg profiles in these cores accurately depict historical releases of Hg to the river bed. The influence of federal regulations in the early 1970s to restrict Hg emissions to the river was apparent in these dated sediment cores, as were the closures of several local industries in the mid 1990s. Mercury accumulation rates prior to 1970 were 60 times higher than those occurring after 1995. Methyl mercury showed surface enrichment in most of these sediment cores providing evidence that mercury methylation occurred most rapidly near the sediment surface. PMID:19394069

Delongchamp, Tania M; Lean, David R S; Ridal, Jeffrey J; Blais, Jules M

2009-06-15

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 4 km and 10 km 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 4 km 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

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

229

Estuary Live!  

NSDL National Science Digital Library

Classrooms and individuals can log on to participate in a real-time field trip to a National Estuary Research Reserve. Ask questions, view live video and still images, and learn about estuaries from experts. Topics range from geology to water quality, estuary plants and animals, and cultural heritage. Includes: references and lesson plans, classroom activities and teachers' guides. Archives of previous years are available, featuring sessions from East, West and Gulf Coast estuaries.

230

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

E-print Network

. Lawrence River yellow perch (Perca flavescens) Magali Houde a, , Maeva Giraudo a , Mélanie Douville activities to histological changes. Yellow perch (Perca flavescens) were selected based on their wide

Bernatchez, Louis

231

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

232

Exploring Estuaries  

NSDL National Science Digital Library

Defines estuaries and related habitats, reviews their roles in coastal ecology and in supporting human activities. Virtual tours provide history and introduce ecology of representative plans and animals. Presents current threats to estuaries and their wildlife and explains the role of EPA's National Estuary Program in protecting these important coastal resources. Includes: teachers' page with resources and links; games, coloring sheets and glossary for kids.

233

Exploring Estuaries  

NSDL National Science Digital Library

Defines estuaries and related habitats, reviews their roles in coastal ecology and in supporting human activities. Virtual tours provide history and introduce ecology of representative plans and animals. Presents current threats to estuaries and their wildlife and explains the role of EPA's National Estuary Program in protecting these important coastal resources. Includes: teachers' page with resources and links; games, coloring sheets and glossary for kids.

2011-07-08

234

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.

235

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

236

Occurrence of alkylphenols and alkylphenol mono- and diethoxylates in natural waters of the Laurentian Great Lakes basin and the upper St. Lawrence River  

Microsoft Academic Search

Nonylphenol and its ethoxylates are on the second priority substances list (PSL2) to determine if they are ‘toxic’ as defined under the Canadian Environmental Protection Act. This study addresses the need for data on their occurrence in surface waters and sediments in Canada. Samples of surface water from 35 sites in the Laurentian Great Lakes basin and the upper St.

D. T. Bennie; C. A. Sullivan; H.-B. Lee; T. E. Peart; R. J. Maguire

1997-01-01

237

The Social Nature of Saintliness and Moral Action: A View of William James's "Varieties" in Relation to St Ignatius and Lawrence Kohlberg  

ERIC Educational Resources Information Center

This article argues that William James's thinking in "The Varieties" and elsewhere contains the view that social institutions, such as religious congregations and schools, are mediators between the private and public spheres of life, and are necessary for transforming personal feelings, ideals and beliefs into moral action. The Exercises of St

Higgins-D'Alessandro, Ann; Cecero, John J.

2003-01-01

238

Estuary Restoration Act Estuary Habitat Restoration Council  

E-print Network

Estuary Restoration Act Estuary Habitat Restoration Council Ranked Proposal Recommendations June 12 estuary restoration efforts and to contribute to the Puget Sound Partnership's Action Agenda recovery goal Restoration for Ecosystem Services and Fish Habitat in Great Bay Estuary, NH The project will restore 10 acres

US Army Corps of Engineers

239

Estuary Restoration Act Estuary Habitat Restoration Council  

E-print Network

Estuary Restoration Act Estuary Habitat Restoration Council Ranked Proposal Recommendation May 13 planting of a native sea urchin. Recommend NOAA fund 8. Salt Creek Estuary, Will remove portions of two it to its historic size of 77 acres. Recommend USACE fund. #12;9. Skokmish Estuary Will re

US Army Corps of Engineers

240

Estuary Habitat Restoration INTRODUCTION  

E-print Network

1 Estuary Habitat Restoration STRATEGY 2012 INTRODUCTION The Estuary Restoration Act of 2000 (ERA agencies to maximize benefits derived from estuary habitat restoration projects and address the pressures facing our nation's estuaries. The ERA established an inter-agency Estuary Habitat Restoration Council

US Army Corps of Engineers

241

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

242

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

243

ERNESTORLANDO LAWRENCE BERKELEY NATIONALLABORATORY  

E-print Network

. Department of Commerce 5285 Port Royal Road, Springfield, VA 22161 Ernest Orlando Lawrence Berkeley National-domainsolutionsfor nonlinear elastic 1-Dplane wave propagation Valeri A Korneev Earth Sciences Division Ernest OrlandoLawrenceERNESTORLANDO LAWRENCE BERKELEY NATIONALLABORATORY TimeDomain Solutions for Nodhear Elastic 1=D

Korneev, Valeri A.

244

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

245

National Estuaries Day  

NSDL National Science Digital Library

Get the most out of National Estuaries Day (October 5, 2002) by visiting this Web site from the National Oceanic and Atmospheric Administration (NOAA). Follow a link to Estuary Live!, which offers online interactive fieldtrips through a number of estuaries around the nation. Guided tours of eight estuaries will be webcast live October 3 and 4, supplemented by videos from a number of other estuaries. Internet participants "will have an opportunity to see the fascinating creatures that make estuaries their home and experience the diversity of estuarine ecosystems." Viewers may submit questions during the webcasts or videos, which will be answered by tour guides and educators from the featured estuaries. Click on About Estuaries for an introduction to estuarine ecosystems and for links to a number of Web sites that "provide general information, curriculums and helpful references on estuaries."

2002-01-01

246

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

247

Introduction to Estuaries  

EPA Science Inventory

Estuaries, although minor geographical features at the global scale, have major importance for society and the world?s economies. This chapter introduces estuaries by presenting an overview of definitions, origins, physical, chemical and ecological attributes, and the interaction...

248

ERNEST ORLANDO LAWRENCE BERKELEYNATIONALLABORATORY  

E-print Network

LBNL-41914 ERNEST ORLANDO LAWRENCE BERKELEYNATIONALLABORATORY Nonlinear Interaction of Plane Port Royal Road, Springfield, VA 22161 Ernest Orlando Lawrence Berkeley National Laboratory is an equalInteractionof Plane Elastic Waves Valeri A Korneev, Kurt T Nihei and Larry RMyer Earth Sciences Division Ernest

Korneev, Valeri A.

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

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

251

Down and Out on the Kaw: An Examination of Emergency Shelters in Lawrence, Kansas.  

E-print Network

Homelessness poses an enduring and formidable challenge to 21st-century urban America. My work draws from three years of ethnographic research on the streets and in the social service agencies of Lawrence, Kansas. I formally ...

McCrary, Quincy Dalton

2008-07-25

252

Estuary Data Mapper  

EPA Science Inventory

The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary has three elements: an estuarine geo-referenced relational database, watershed GIS coverages, and tools to support decision-making. To facilita...

253

DYNAMIC ESTUARY MODEL PERFORMANCE  

EPA Science Inventory

Applications of the Dynamic Estuary Model (DEM) to both the Delaware and Potomac Estuaries by the Environmental Protection Agency during the 1970s are summarized and evaluated. Methods for calibrating, refining, and validating this model, and statistics for evaluating its perform...

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

Estuary Classification Revisited  

E-print Network

The governing equations of a tidally averaged, width averaged, rectangular estuary has been investigated. It's theoretically shown that the dynamics of an estuary is entirely controlled by three parameters: (i) the Estuarine Froude number, (ii) the Tidal Froude number and (iii) the Estuarine Aspect ratio. The momentum, salinity and integral salt balance equations can be completely expressed in terms of these control variables. The estuary classification problem has also been reinvestigated. It's found that these three control variables can completely specify the estuary type. Comparison with real estuary data shows very good match. Additionally, we show that the well accepted leading order estuarine integral salt balance equation is inconsitent with the leading order salinity equation in an order of magnitude sense.

Guha, Anirban

2012-01-01

256

SAN FRANCISCO ESTUARY INSTITUTE CONTRIBUTION  

E-print Network

SAN FRANCISCO ESTUARY INSTITUTE CONTRIBUTION NO. 574 JUNE 2008 7770 Pardee Lane, Second floor in the San Francisco Estuary by Bruce Thompson and Sarah Lowe San Francisco Estuary Institute Bays and Estuaries provide a new framework and methods for assessment of sediment condition in San

257

Ernest Orlando Lawrence  

Microsoft Academic Search

In his relatively short life of 57 years, Ernest Orlando Lawrence accomplished more than one might believe possible in a life twice as long. The important ingredients of his success were native ingenuity and basic good judgement in science, great stamina, an enthusiastic and outgoing personality, and a sense of integrity that was overwhelming. Many articles on the life and

Luis W

1967-01-01

258

Learning Lessons from Estuaries  

NSDL National Science Digital Library

There is something that draws us all 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. This article describes annual trips to three islands in the Chesapeake Bay and the long-term impact these trips have had on students. Although the activities described in this article are centered around the Bay, this example of an immersive field experience could be duplicated in other ecosystems around the country (see "On the web" at the end of this article for information on planning an estuary field trip).

Schnittka, Christine

2006-01-01

259

Lawrence Hall of Science  

NSDL National Science Digital Library

Lawrence Hall of Science is a resource center for preschool through high school science and mathematics education, and a public science center with hands-on experiences for learners of all ages. Home of the William Knox Holt Planetarium, there is extensive educational programming centered on astronomy, including Planetarium Activities for Student Success kits for purchase that illustrate basic principles of astronomy. Earthquakes, erosion, wind and weather are the focus of the Forces that Shape the Bay exhibits, and there are also a number of exhibits highlighting math and physics. The website provides many online games and home activities available for download. The Lawrence Hall of Science Center for Curriculum Innovation creates instructional materials in mathematics and science for preschool through 12th graders for use by students, teachers and other educators, parents and families, and the website provides an array of information on the various programs. Title II funding for professional development is available.

260

Volunteer Estuary Monitoring  

NSDL National Science Digital Library

This online method manual from EPA describes how to conduct estuary monitoring programs, with step-by-step guides for chemical, physical and biological sampling and data interpretation. Also describes how to plan and maintain a volunteer force, with tips on liability and financial issues, volunteer recruiting training and retention. Addresses quality assurance so that results have weight. Provides an overview of estuarine science, threats to estuaries and some solutions.

261

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

262

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.

263

Lawrence CV 1 Shawn A. Lawrence, PhD, LCSW  

E-print Network

of the Early Truancy Intervention (ETI) program. School Social Work Journal, 35(2), 57-71. Lawrence, S. A's adherence to medication and treatment. Journal of Human Behavior in the Social Environment, 19(7), 859.lawrence@ucf.edu Employment: Current Position: 5/2013-Present Interim MSW Program Coordinator 8/2005-Present Associate

Wu, Shin-Tson

264

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 58752 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Laboratory Evaluation of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. 3 #12;Abstract A testing program was undertaken at Lawrence Berkeley National Laboratory and an electric utility

265

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

266

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 53606 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Improving Air Handler Efficiency thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Department Lawrence Berkeley National Laboratory Berkeley, CA. 94720, USA ABSTRACT In continuing

267

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

268

LBNL-6288E ERNEST ORLANDO LAWRENCE  

E-print Network

1 LBNL-6288E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley Lawrence Berkeley National Laboratory Reprint version of journal article

269

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-58252 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Rationale for Measuring Duct thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Division Ernest Orlando Lawrence Berkeley National Laboratory University of California Berkeley, California

270

Lawrence Denny Lindsley Photographs  

NSDL National Science Digital Library

Lawrence Denny Lindsley was born in 1878 in a house on scenic Lake Union, right in the middle of the relatively young city of Seattle, Washington. As a descendant of the early Seattle pioneer David Denny, Lindsley began to wander around the city and its environs from a young age. Like many men in the Pacific Northwest during the late 19th century, he enjoyed the outdoors, and soon developed a skill for photography. He later went on to work for Edward Curtis, and he continued on by documenting such landscapes as Mount Rainer, Lake Chelan, and the Olympic Peninsula. Many of these excellent photographs can be viewed in this latest offering from the University of Washington Libraries Digital Collection. All told, there are 472 photographs here, complete with detailed records. The King County section is a real highlight, as visitors will get a real sense of the area before it became heavily urbanized during the 20th century.

2006-01-01

271

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 43382 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Evaluation of PEGIT Duct Connection of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. 2 #12

272

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 54767 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Duct Tape Durability Testing M of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. Legal

273

DELAWARE ESTUARY PCB MODEL  

EPA Science Inventory

The Delaware River Basin Commission recently completed the first phase of a program to develop and implement Total Maximum Daily Loads (TMDLs) for toxic pollutants for the Delaware Estuary. This complex body of water extends from the head of tide at Trenton, NJ (River Mile 133.2...

274

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,...

275

Grounded Cognition Lawrence W. Barsalou  

E-print Network

Grounded Cognition Lawrence W. Barsalou Department of Psychology, Emory University, Atlanta reserved 0066-4308/08/0203-0617$20.00 Key Words cognitive architecture, imagery, representation, simulation, situated action Abstract Grounded cognition rejects traditional views that cognition is com- putation

Coulson, Seana

276

Introduction: Lawrence Kohlberg as Mentor.  

ERIC Educational Resources Information Center

Recognizes Lawrence Kohlberg as the foremost contributor to moral education during the twentieth century. Analyzes the mentor-student relationship and discusses Kohlberg's mentor relationship with his students. (KO)

Boyd, Dwight

1988-01-01

277

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

278

Monitoring Requirements Under the Estuary Restoration Act The Estuary Restoration Act directs NOAA to develop standard monitoring protocols for estuary  

E-print Network

Monitoring Requirements Under the Estuary Restoration Act The Estuary Restoration Act directs NOAA to develop standard monitoring protocols for estuary habitat restoration projects. This document summarizes critical elements must be included in monitoring plans for projects supported by Estuary Restoration Act

US Army Corps of Engineers

279

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

280

Estuary Restoration Act of 2000 Title I of Estuaries and Clean Waters Act of 2000  

E-print Network

Estuary Restoration Act of 2000 Title I of Estuaries and Clean Waters Act of 2000 Public Law 106 of the Estuary Restoration Act, Title I of P.L. 106-457 (Act). The contents reflect the views of the Estuary). Background: The purposes of the Act are to promote the restoration of estuary habitat; develop a national

US Army Corps of Engineers

281

Ecology of estuaries: Anthropogenic effects  

Microsoft Academic Search

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

Kennish; Michael J. Kennish

1992-01-01

282

SAN FRANCISCO ESTUARY INSTITUTE CONTRIBUTION  

E-print Network

Williams San Francisco Estuary Institute In collaboration with San Francisco Estuary partners including: Heather Kerkering1 , Chris Farrar2 and Collin Eagles-Smith2 1 Central and Northern California Ocean Network Pilot Study Report Katie Harrold, Sarah Lowe, Mike Connor, and Meredith Williams (San Francisco

283

HAMILTON ST HAMILTON ST  

E-print Network

KOSSUTH PARK R A R I T A N R I V E R GEORGEST GEORGEST EASTON AVE EASTON AVE HAMILTON ST HAMILTON Observatory University Center at Easton Avenue Gateway University Press Barnes & Noble at Rutgers Catholic Canterbury House 64 College Ave Career Services 73 Easton Avenue IEEE History Center Bildner Center

Hanson, Stephen José

284

Environmental Setting of the San Francisco Estuary  

E-print Network

r.a.lEidy 15 PArT II Environmental Setting of the San Francisco Estuary above diablo range, alameda EnvironmEntal SEtting of thE San franciSco EStUary 1 watershed Characteristics location, Size). Surface area of the Estuary is approximately 1,240 km2 (Conomos et al., 1985). It is an inland estuary

285

Deborah Lawrence, CV January 2013 1 DEBORAH LAWRENCE  

E-print Network

1989 Harvard University, Biological Anthropology, Magna Cum Laude PROFESSIONAL EXPERIENCE 2012-present) Peer-reviewed journal articles 1. *Tully, K., T. Wood, A. Schwantes and D. Lawrence. In press In press. Physical and Biological Feedbacks of Deforestation. Reviews of Geophysics. 4. *Tully, K., and D

Lawrence, Deborah

286

Lawrence CV 1 Shawn A. Lawrence, PhD, LCSW  

E-print Network

Intervention (ETI) program. School Social Work Journal 35(2), 57-71. Lawrence, S. A., & Hazlett, R. & Mazur's adherence to medication and treatment. Journal of Human Behavior in the Social Environment, 19(7), 859: slawrence15@cfl.rr.com Current Position: 8/2005-Present Associate Professor (Promoted Fall 2011) University

Van Stryland, Eric

287

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

288

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

289

Joseph S. Miller Lawrence S. Moss  

E-print Network

Joseph S. Miller Lawrence S. Moss The Undecidability of Iterated Modal Relativization Abstract and Lawrence S. Moss also assume that none of the children can see their own foreheads and that all children

Miller, Joseph S.

290

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-56292 LBNL 56292 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Efficacy of Intermittent Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence

291

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 57330 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY State-of-the-art in Residential of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. 3 #12

292

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 54005 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Register Closing Effects on Forced Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence

293

MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL  

E-print Network

1 MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL NOAA Headquarters 1315 East group presented status updates on current workgroup priorities, including the Estuary Restoration Act, Estuary Restoration Habitat Strategy and Action Plan, and the National Ocean Policy. The Estuary

US Army Corps of Engineers

294

Toward delisting of the water quality beneficial use impairment in the St. Louis River, MN: A monitoring approach  

EPA Science Inventory

Water quality in the St. Louis River Estuary (SLRE), a great lakes area of concern (AOC), is improving. A significant leap forward followed the opening of the Western Lake Superior Sanitary District in 1978. However, desire for continued improvement throughout the estuary was the...

295

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

296

LAWRENCE BERKELEY NATIONAL LABORATORY About Berkeley Lab  

E-print Network

and energy research. Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist whoLAWRENCE BERKELEY NATIONAL LABORATORY About Berkeley Lab Berkeley Lab is a U.S. Department accelerator that opened the door to high-energy physics. It was Lawrence's belief that scientific research

Eisen, Michael

297

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 54696 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY A Systems Approach to Retrofitting of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;AWilliams, Energy Performance of Buildings Group Lawrence Berkeley National Laboratory, Berkeley, CA ABSTRACT A Best

298

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

299

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 59620 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Ventilation Behavior and Household the accuracy or adequacy of this information in this report. Ernest Orlando Lawrence Berkeley National and the Lawrence Berkeley National Laboratory under the sponsorship of the California Air Resources Board

300

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-63193 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Multizone Age-of-Air Analysis MAX H thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Energy Performance of Buildings Group Lawrence Berkeley National Laboratory1 ABSTRACT Age of air

301

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

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

302

LBNL/PUB-5515 Ernest Orlando Lawrence  

E-print Network

LBNL/PUB-5515 Report on Ernest Orlando Lawrence Berkeley National Laboratory Laboratory Directed Research and Development Program FY 2006 Ernest Orlando Lawrence Berkeley National Laboratory Berkeley, CA of California. Lawrence Berkeley Laboratory is an equal opportunity employer. #12;iii Table of Contents

303

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 42127 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Distribution System Leakage Impacts of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. 1 #12, ventilation. Iain S. Walker is a staff scientist at Lawrence Berkeley National Laboratory, Berkeley, CA

304

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

305

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

306

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 it owns in Richmond, California, for consolidation of biosciences programs of the Lawrence Berkeley

Eisen, Michael

307

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

308

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-6607E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Measurement-Based Evaluation thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National of the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy under Lawrence Berkeley

309

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

310

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 57225 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Duct Tape and Sealant Performance I of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. Legal, it is important to understand how duct tape works for its ostensible purpose--to seal ducts. At the Lawrence

311

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

312

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 54496 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Houses Need to Breathe...Right? M Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence Environment Department Lawrence Berkeley National Laboratory One Cyclotron Road Berkeley, CA 94720 October

313

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

314

Dissolved oxygen in two Oregon estuaries: Importance of the ocean-estuary connection  

EPA Science Inventory

We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

315

Dissolved oxygen in two Oregon estuaries: The importance of the ocean-estuary connection  

EPA Science Inventory

We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

316

Dissolved oxygen in two Oregon estuaries: Importance of the ocean-estuary connection - March 2011  

EPA Science Inventory

We examined the role of the ocean?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO w...

317

Estuary Restoration Act of 2000 Title I of Estuaries and Clean Waters Act of 2000  

E-print Network

Estuary Restoration Act of 2000 Title I of Estuaries and Clean Waters Act of 2000 Public Law 106 of Section 108 of the Estuary Restoration Act, Title I of P.L. 106-457 (Act). This report covers the fiscal years 2004 through 2006 and reflects the views of the Estuary Habitat Restoration Council (Council

US Army Corps of Engineers

318

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.

319

Lawrence Ip Vazirani Class #2  

E-print Network

Lawrence Ip Vazirani Class #2 Friday September 8 2000 Hilbert Spaces, Tensor Products and Quan­ tum Circuits 1 Inner Products Let V be a vector space. An inner product on V is a map (\\Delta; \\Delta) : V \\Theta V ! C such that: ffl (v; v) â?? 0 ffl v 6= 0 ) (v; v) ? 0 ffl (ffu + fiv; w) = ff(u; w) + fi(v; w

Vazirani, Umesh

320

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...

321

EXHIBIT OF EMPACT ESTUARY MONITORING HANDBOOKS  

EPA Science Inventory

Related EMPACT documents were displayed at the National Estuary Day Celebration held in Washington, DC, September 30-Octuber 4, 2002. The estuary monitoring technology transfer handbooks displayed were prepared based on information and monitoring technologies developed from selec...

322

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.

323

MACROINVERTEBRATE PROTOCOLS ON ESTUARIES IN NEW JERSEY  

EPA Science Inventory

Estuaries of the Atlantic coastal New Jersey extend from Newark Bay southward to Cape May Inlet. The rich diversities of habitats found in these estuaries provide important nursery areas for fish and marine invertebrates. Federal and state agencies routinely monitor estuaries fo...

324

Ecotone or Ecocline: Ecological Boundaries in Estuaries  

Microsoft Academic Search

Two main ecological boundaries, ecotone and ecocline, have been defined in landscape ecology. At this scale, the estuary represents a boundary between rivers and the sea, but there has been no attempt to fit empirical data for estuaries to these boundary models. An extensive data set from the Thames estuary was analysed using multivariate techniques and species-range analysis, in order

M. J Attrill; S. D Rundle

2002-01-01

325

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...

326

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

327

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

328

A multidisciplinary study of hypoxia in the deep water of the Estuary and Gulf of  

E-print Network

seemed much more difficult if the wonderful people who accompanied me throughout this journey would his passion of science with me. Although not an official member of my advisory committee, I want support and the many passionate discussions we had about the St. Lawrence ecosystem over the past 5 years

Barnes, Sarah-Jane

329

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.

330

Estuary program primer. National Estuary Program. Draft report  

SciTech Connect

The manual provides an overview of the National Estuary Program and its functions and management structure. The manual also describes the Comprehensive Conservation and Management Plan, a framework that can be used to help in prevention and control of pollution, land over-use, and man-environment conflicts.

Not Available

1987-10-01

331

Credit: Michael Anderson. NOAA Selects St. Louis River Estuary as  

E-print Network

walleye, lake sturgeon, and smallmouth bass. But the bay was impacted by sawmilling debris, which degraded, draining into western Lake Superior. The area is a major tourism draw and home to the country's busiest measurable results in the next three to five years. Other partners in the restoration effort include the Lake

332

Subtidal variability in water levels inside a subtropical estuary  

NASA Astrophysics Data System (ADS)

time series of water level are analyzed at five locations along the St. Johns River Estuary, Florida, to investigate propagation of subtidal pulses. Hilbert-transformed Empirical Orthogonal Functions (HEOFs) are obtained after a dominant seasonal signal is extracted from the data. These functions provide information on spatial structure and propagation phase of subtidal water level pulses. The first HEOF mode explains 96% of the subtidal variability and features an unusual spatial structure: amplitude attenuation (averaging 1 mm/km) to 55 km upstream, slight amplification (0.16 mm/km) over the middle 70 km, and attenuation (2.3 mm/km) over the final 18 km of the estuary. The phase suggests a shift from progressive to quasi-standing wave behavior at 55 km from the estuary mouth. Additionally, local minima in the phase suggest two sources of subtidal forcing: the coastal ocean and the upstream end. An analytical model describing the evolution of long waves through a channel with frictional damping is fit to the amplitude of HEOF mode 1. Solutions are obtained as a function of two parameters: the nondimensional length of the basin, ?, and the nondimensional frictional depth, ?. Values of ? between 0.55 and 0.67 and ? between 1.45 and 1.7 provide the best fit with the HEOF results (1% error or less). These values indicate a highly frictional environment in which the average subtidal wavelength is 10 times the basin length. Subtidal pulses in this estuary, therefore, behave as damped waves that can be represented with idealized models.

Henrie, Krista; Valle-Levinson, Arnoldo

2014-11-01

333

Monitoring and Managing Contamination in the San Francisco Estuary 199399  

E-print Network

Estuary Monitoring and Managing Contamination in the San Francisco Estuary 1993­99 pulse of the #12 in the Estuary and watch for new problems, as well as efforts by environmental managers to reduce existing of the San Francisco Estuary Regional Monitoring Program (RMP), administered by the San Francisco Estuary

334

LAKE PONTCHARTRAIN ESTUARY CONSERVATION PLAN  

EPA Science Inventory

The Nature Conservancy will conduct a series of a least four science expert workshops to develop a Site Conservation Plan for the Lake Pontchartrain Estuary and adjacent wetlands. The objective of the Site Conservation Plan is to identify conservation targets, threats or stresse...

335

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

336

Food Webs in an Estuary.  

ERIC Educational Resources Information Center

The Maryland Marine Science Education Project has produced a series of mini-units in marine science education for the junior high/middle school classroom. This unit focuses on food chains in an estuary. Although the unit specifically treats the Chesapeake Bay, it may be adapted for use with similar estuarine systems. In addition, the unit may be…

Dunne, Barbara B.

337

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-59041 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Development of a Mathematical Air Government or any agency thereof, or The Regents of the University of California or any other sponsor. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. This work was also

338

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July thereof or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Site Environmental Report for 2003 Volume I JULY 2004 Ernest

339

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL-57236 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Review of Literature Related Government or any agency thereof, or The Regents of the University of California or any other sponsor. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;Abstract This paper

340

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July Report for 2002 Volume II July 2003 Ernest Orlando Lawrence Berkeley National Laboratory Prepared of the United States Government or any agency thereof or The Regents of the University of California. Ernest

341

Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Ernest Orlando Lawrence Berkeley National Laboratory Environment, Health, and Safety Division July Report for 2002 Volume I JULY 2003 Ernest Orlando Lawrence Berkeley National Laboratory Prepared of the United States Government or any agency thereof or The Regents of the University of California. Ernest

342

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

1 LBNL 57730 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Review of Residential Ventilation the Energy Commission passed upon the accuracy or adequacy of the information in this report. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. LBNL-57730 #12;3 Abstract

343

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 51551 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Evaluation of Commercially of the United States Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. 2 #12;Evaluation

344

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 54760 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Improving Air Handler Efficiency of the United States Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. 2 #12;Improving Air

345

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 of the United States Government or any agency thereof, or The Regents of the University of California. Ernest

346

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 53811 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Ventilation Technologies Scoping of the United States Government or any agency thereof, or The Regents of the University of California. Ernest Orlando Lawrence Berkeley National Laboratory is an equal opportunity employer. #12;VENTILATIONS STANDARDS

347

Lawrence and Harlem: Reviving Transit Friendly Areas  

E-print Network

Commercial corridors: Broadway, Lawrence, Sheridan Near several arterial streets Commercial corridors: Lake Street REVIVED #12;+ Revival The area around the Lawrence stop is bustling with commercial activity Harlem =StationEntrances 100 m 100 m INTRO #12;+ PATTERN: Streets & Stations Near many arterial streets

Illinois at Chicago, University of

348

JAMES A. DAVIS Lawrence Berkeley National Laboratory  

E-print Network

JAMES A. DAVIS Lawrence Berkeley National Laboratory Mail Stop 90-1106 1 Cyclotron Road Berkeley, Lawrence Berkeley National Laboratory 1980-2010: Senior Research Scientist, U.S. Geological Survey, Water and in differing geochemical regimes, including studies of how the transport of uranium(VI), arsenic(V) and arsenic

Hazen, Terry

349

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

350

78 FR 66265 - Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY AGENCY: Coast Guard...Bridge, mile 0.4, across Reynolds Channel, at Lawrence, New York. This temporary...Atlantic Beach Bridge, across Reynolds Channel, mile 0.4, at Lawrence, New...

2013-11-05

351

78 FR 56609 - Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY AGENCY: Coast Guard...Bridge, mile 0.4, across Reynolds Channel, at Lawrence, New York. The owner of...Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY'', in the Federal...

2013-09-13

352

78 FR 56610 - Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY AGENCY: Coast Guard...Bridge, mile 0.4, across Reynolds Channel, at Lawrence, New York. This temporary...Atlantic Beach Bridge, across Reynolds Channel, mile 0.4, at Lawrence, New...

2013-09-13

353

78 FR 34893 - Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...Drawbridge Operation Regulations; Reynolds Channel, Lawrence, NY AGENCY: Coast Guard...Bridge, mile 0.4, across Reynolds Channel, at Lawrence, New York. This temporary...Atlantic Beach Bridge, across Reynolds Channel, mile 0.4, at Lawrence, New...

2013-06-11

354

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

355

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 University of Londrina, Brazil, 1983 Professional Experience Staff Scientist, Lawrence Berkeley National Laboratory, 2003 Computer Systems Engineer III, Lawrence Berkeley National Laboratory, 19962003 Assistant

Marques, Osni

356

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

357

Carbon dioxide emissions from Indian monsoonal estuaries  

NASA Astrophysics Data System (ADS)

Estuaries are known to be strong source for atmospheric CO2, however, little information is available from Indian estuaries. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge (wet) period. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ˜300 and 18492 ?atm which are within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

Sarma, V. V. S. S.; Viswanadham, R.; Rao, G. D.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Kumar, N. A.; Rao, D. B.; Sridevi, T.; Krishna, M. S.; Reddy, N. P. C.; Sadhuram, Y.; Murty, T. V. R.

2012-02-01

358

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

359

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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

360

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...

361

MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL  

E-print Network

1 MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL NOAA Headquarters 1315 East Group member, gave an overview of the estuary habitat restoration project solicitation process. Port Susan Bay Estuary Restoration, Washington will reintroduce the full tidal prism and inundation

US Army Corps of Engineers

362

PRIMARY RESEARCH PAPER Estuary hydrogeomorphology affects carbon sources  

E-print Network

PRIMARY RESEARCH PAPER Estuary hydrogeomorphology affects carbon sources supporting aquatic The relative importance of carbon sources supporting aquatic food webs within and among estuaries may to examine (1) the relative importance of carbon sources supporting estuarine consumers among estuaries

Hoeinghaus, David J.

363

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 in a branched estuary R. SMITH Department of Mathematical Sciences, Loughborough University, LE11 3TU, U.K. e of a narrow estuary, the resulting maximum concentration or temperature can vary markedly depending upon

364

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

365

Ernest Orlando Lawrence (1901-1958), Cyclotron and Medicine  

Microsoft Academic Search

On August 8, 2001, Lawrence Berkeley National Laboratory celebrated the centennial of the birth of its founder (and namesake), Ernest Orlando Lawrence. For the occasion, many speeches were given and old speeches were remembered. We recall the words of the late Luis Alvarez, a Nobel Laureate and one of the Lawrence's closest colleagues: ''Lawrence will always be remembered as the

William T

2005-01-01

366

-Grobner Bases After lectures by Professor Lawrence  

E-print Network

-Gr¨obner Bases After lectures by Professor Lawrence James H. Davenport J to a question of JHD. 4JHD: Prof Lawrence called it -division, but it's more akin to reduction. 5JHD[H/A]-module, with h · a = hah-1 , for a A, h H/A, which we will write ah , and then a nihi = (ani ) hi . Then W(V1U1

Davenport, James

367

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.

368

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...

369

A Climate Ready Estuaries Vulnerability Assessment  

EPA Science Inventory

The purpose of the the Climate Ready Estuaries program is to build capacity in the National Estuary Programs (NEPs) for local leadership and expertise to adapt to the effects of climate change through a joint effort with the NEPs and EPA. Background The Climate Ready...

370

Dissolved Oxygen Data for Coos Estuary (Oregon)  

EPA Science Inventory

The purpose of this product is the transmittal of dissolved oxygen data collected in the Coos Estuary, Oregon to Ms. Molly O'Neill (University of Oregon), for use in her studies on the factors influencing spatial and temporal patterns in dissolved oxygen in this estuary. These d...

371

Estuary Habitat Restoration Council ACTION PLAN  

E-print Network

Estuary Habitat Restoration Council ACTION PLAN 2012 The purpose of this Action Plan is to support the 2012 Estuary Habitat Restoration (EHR) Strategy by identifying specific actions and milestones Service (NRCS). Several federal agencies fund and implement coastal and estuarine habitat restoration

US Army Corps of Engineers

372

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.

373

AFS Estuaries Section - A Successful Partnership  

EPA Science Inventory

The Estuaries Section of the American Fisheries Society offers travel awards to students in support of their attendance and presentations at the AFS meeting. Since 2007, the Southern Association of Marine Laboratories has partnered with the Estuaries Section to sponsor two stude...

374

RMP Annual Monitoring Results San Francisco Estuary Institute and the  

E-print Network

RMP Annual Monitoring Results San Francisco Estuary Institute and the Regional Monitoring Program for Water Quality in the San Francisco Estuary · #12;#12;RMP Annual Monitoring Results San Francisco Estuary Institute and the Regional Monitoring Program for Water Quality in the San Francisco Estuary · December 2006

375

CotancheSt. Johnston St.  

E-print Network

CAFETERIA BATE BLDG. M M M M M M M M M SCIENCE & TECH BREWSTER RIVERS JENKINS MENDENHALL WILLIS BELK Todd. Bldg. HARRIS BLDG. Tenth St. S S P P P Minges Coliseum Murphy Center RockSprings MCGINNIS M MESSICK

376

Cameron Ave. Franklin St.  

E-print Network

4 15 6 3 17 16 12 14 10 1 2 5 8 7 Cameron Ave. Co Franklin St. Pittsboro Rosemary St. RaleighSt. St, Government Info., Maps Collection and Microforms Collection 4 Geological Sciences Library Mitchell Hall, Room

Whitton, Mary C.

377

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

378

Dissolved oxygen in two Oregon estuaries: The importance of the ocean-estuary connection - May 16, 2011  

EPA Science Inventory

We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

379

St. Lucia.  

PubMed

The population of St Lucia was 123,000 in 1986, with an annual growth rate of 2%. The infant mortality rate stands at 22.2/1000 live births, and life expectancy is 70.3 years for males and 74.9 years for females. The literacy rate is 78%. St Lucia's labor force is allocated as follows: agriculture, 36.6%; industry and commerce, 20.1%; and services, 18.1%. The gross national product (GNP) was US$146 million in 1985, with an annual growth rate of 3% and a per capita GNP of $1071. St Lucia is a parliamentary democracy modeled on the British Westminster system. The island is divided into 16 parishes and 1 urban area (the capital, Castries). St Lucia is currently a politically stable country, although the high level of youth unemployment is a cause for concern. Ongoing stability may depend on the government's ability to provide services such as jobs and housing. The economy has evolved from a monocrop sugar plantation type to a diversified economy based on agriculture, industry, and tourism. Agriculture, dominated by the banana industry, is characterized by the participation of a large number of small and medium-sized enterprises. Industry is being encouraged through the provision of incentives such as tax rebates. The government is attempting to maintain a sound investment climate through a tripartite dialogue with the private sector and trade unions. Overall economic policy is predicated on the attraction of sound investments, by both local and foreign entities, to accelerate the rate of economic growth, solve the unemployment problem, and generate a solid balance-of-payments position. PMID:12177918

1987-06-01

380

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...

381

75 FR 17382 - Small Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Water...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Russian River Estuary Water Level Management Activities, California AGENCY: National...River Estuary (Estuary) water level management and monitoring activities at the mouth...incidental to estuary water level management events and monitoring activities....

2010-04-06

382

Late Summer Trophic Conditions in the North-east Gulf of Finland and the River Neva Estuary, Baltic Sea  

NASA Astrophysics Data System (ADS)

Trophic conditions and hydrography of the whole north-east Gulf of Finland in both the Finnish and the Russian waters, including the Neva Estuary, were for the first time extensively explored in August 1990. The Neva Estuary was defined on the basis of hydrographical and geomorphological characteristics. The results revealed extensive and strong increasing gradients in nutrients, bio-masses of phytoplankton (especially filamentous blue-green algae) and primary productivity, as well as in the bio-masses of several heterotrophic organisms from the open Gulf towards the inner Neva Estuary. The basic cause of these phenomena is the high and continuous load of nutrients and organic matter from St Petersburg and the River Neva, together with the typical estuarine hydrography and huge reserves of inorganic nutrients immediately below the mixed surface layer. Under typical late summer conditions immediate effects of the River Neva and the St Petersburg region cover the whole estuary ( c. 3000 km 2), i.e. 10% of the surface area of the whole Gulf, but do not reach the open parts of the Gulf or the Finnish territorial waters. However, recycled effects, as well as effects of the huge sub-thermocline nutrient resources, clearly increase the productivity of the whole north-east Gulf and cause the general tendency of increasing eutrophy towards east in the whole Gulf of Finland.

Pitkänen, H.; Tamminen, T.; Kangas, P.; Huttula, T.; Kivi, K.; Kuosa, H.; Sarkkula, J.; Eloheimo, K.; Kauppila, P.; Skakalsky, B.

1993-11-01

383

Lattice Boltzmann Hydrodynamic and Transport Modeling of Everglades Mangrove Estuaries  

NASA Astrophysics Data System (ADS)

Lattice Boltzmann methods are being developed and applied to simulate groundwater and surface water flows, and heat, solute, and particle transport. Their ability to solve Navier-Stokes, St. Venant, or Darcy equations with closely coupled solute transport and density-dependent flow effects in geometrically complex domains is attractive for inverse modeling of tracer release data and forward modeling of carbon transport in mangrove estuaries under various future conditions. Key physical processes to be simulated include tidal cycles, storm surge, sea level change, variable upstream stage, subsurface groundwater inputs, and precipitation/recharge and their effects on estuary salinity and carbon transport in the estuaries and groundwater beneath the mangroves. Carbon sources and storage in the aquifer and exchanges at the mangrove-estuary interface and carbon transformations in the water column also need to be simulated. Everglades tidal mangrove estuaries are characterized by relatively high velocity (approaching 1 m s-1) tidal flows. The channels are generally less than 2 m in depth. Tidal fluctuations approach 2 m leading to significant areas of periodic inundation and emergence of oyster beds, shell beaches, mangrove root masses, and sandy beaches. Initial models are two-dimensional, although a three-dimensional model explicitly incorporating bathymetry, density-dependent flow, and wind-driven circulation could be developed. Preliminary work highlights some of the abilities of early models. A satellite image of a 64-km2 area surrounding a CO2 flux tower is used to provide the model geometry. Model resolution is 15 m per grid node. A sinusoidal tidal stage variation and constant, high salinity are applied to the Gulf side of the model while a constant stage (corresponding to mean tide), zero salinity boundary is applied on the inland side. The Navier-Stokes equations coupled with the advection-diffusion equation are solved in the open channels. The mangrove areas are simulated as a porous medium, where transport is controlled by the advection-dispersion equation. As expected, incoming tides carry salinity up the channels and outgoing tides tend to flush the salinity from the channels. Salinity also invades the groundwater beneath the mangroves, which then contributes salinity back to the channel during outgoing tides. Although some large-scale aspects of the tidal flows are captured in these preliminary simulations, the current simulations are at Reynolds numbers smaller than those that characterize the real flows. More realistic simulations would require much higher resolution and have to be implemented on large-scale parallel computing platforms possibly using sub-grid turbulence models. Tracer data from experimental releases of SF6 will be used to estimate the parameters controlling transport in the estuary via inverse modeling with the parameter estimation code PEST. SF6 undergoes volatilization from the water column and is therefore a reasonable surrogate for air-sea CO2 gas exchange in the modeling framework. The parameters estimated from the tracer test inversion will be used in predictive modeling of the effects of sea level variations on salinity and carbon transport.

Sukop, M. C.; Engel, V.

2010-12-01

384

The Peel Inlet-Harvey Estuary Study.  

ERIC Educational Resources Information Center

Describes how the department of physics of the Western Australian Institute of Technology (WAIT) has been involved in the Peel Inlet-Harvey Estuary study. An appendix which presents the departmental approach to curriculum matters is also included. (HM)

Walker, Warren; Black, Ronald

1979-01-01

385

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

386

Adaptive optics at Lawrence Livermore National Labratory  

Microsoft Academic Search

Adaptive optics enables high resolution imaging through the atmospheric by correcting for the turbulent air's aberrations to the light waves passing through it. The Lawrence Livermore National Labratory for a number of years has been at the forefront of applying adaptive optics technology to astronomy on the world's largest astronomical telescopes, in particular at the Keck 10-meter telescope on Mauna

Donald T. Gavel

2003-01-01

387

Adaptive Optics at Lawrence Livermore National Laboratory  

Microsoft Academic Search

Adaptive optics enables high resolution imaging through the atmospheric by correcting for the turbulent air's aberrations to the light waves passing through it. The Lawrence Livermore National Laboratory for a number of years has been at the forefront of applying adaptive optics technology to astronomy on the world's largest astronomical telescopes, in particular at the Keck 10-meter telescope on Mauna

Gavel

2003-01-01

388

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

, the impacts of wind energy facilities on residential property values had not previously been investigatedi LBNL-2829E ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY The Impact of Wind Power Projects of Energy Efficiency and Renewable Energy (Wind & Hydropower Technologies Program) of the U.S. Department

Lee, Jason R.

389

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

390

ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

LBNL 53484 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Heat Recovery in Building Envelopes Program, of the U.S. Department of Energy under contract No. DE-AC03-76SF00098. #12;HEAT RECOVERY because of heat recovery within the building envelope. The major objective of this study was to provide

391

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

392

Lawrence E. Carlson Professor of Mechanical Engineering  

E-print Network

Education, American Society of Mechanical Engineers, pp. 31-33. Solar Stirling Engine 2Cam Rock ClimbingPortfolio Lawrence E. Carlson Professor of Mechanical Engineering Founding Co-Director, Integrated Teaching and Learning Program and Laboratory University of Colorado at Boulder #12;ENGINEERING EDUCATION

Carlson, Lawrence E.

393

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

394

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

395

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.

396

Frederick M. Lawrence President and Professor of Politics  

E-print Network

6/14/2011 Frederick M. Lawrence President and Professor of Politics 781-736-3001 lawrence@brandeis.edu Mailstop 001 415 South Street Waltham, Massachusetts 02453-2728 Biography Frederick M. Lawrence took office Research Professor of Law at George Washington University Law School from 2005 to 2010. During his tenure

Fraden, Seth

397

Frederick M. Lawrence President and Professor of Politics  

E-print Network

3/16/2011 Frederick M. Lawrence President and Professor of Politics 781-736-3001 lawrence@brandeis.edu Mailstop 001 415 South Street Waltham, Massachusetts 02453-2728 Biography Frederick M. Lawrence took office Research Professor of Law at George Washington University Law School from 2005 to 2010. During his tenure

Fraden, Seth

398

11. 2.. 30 LBNL-41343 ERNEST ORLANDO LAWRENCE  

E-print Network

11. 2.. 30 LBNL-41343 ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Steady-State Solution Government or any agency thereof. or The Regents of the University of California. Ernest Orlando Lawrence McDermott Technology, Inc. Alliance,OB and **Applied Numerical Algorithm~ Group Lawrence Berkeley

399

Furtive foes: algal viruses as potential invaders Janice E. Lawrence  

E-print Network

Furtive foes: algal viruses as potential invaders Janice E. Lawrence Lawrence, J. E. 2008. Furtive, marine viruses. Received 26 June 2007; accepted 26 January 2008. J. E. Lawrence: Biology Department in phytoplankton population dynamics, Lampert and Sommer (1997) provided the equation l ¼ g þ s þ x þ d þ p þ v

Lawrence, J.E.

400

Draft Environmental Impact Report LAWRENCE BERKELEY NATIONAL LABORATORY  

E-print Network

Draft Environmental Impact Report LAWRENCE BERKELEY NATIONAL LABORATORY LONG-RANGE DEVELOPMENT PLAN Prepared for: Lawrence Berkeley National Laboratory January 22, 2007 #12;225 Bush Street Suite 1700 San Seattle Tampa 201074 Draft Environmental Impact Report LAWRENCE BERKELEY NATIONAL LABORATORY LONG

Lee, Jason R.

401

The Estuary Book: A Guide to Promoting Understanding and Regional Management of Maine's Estuaries and Embayments.  

ERIC Educational Resources Information Center

The objective of this document is to provide information about estuaries, the impact of uses on the environmental health of an estuary, and what communities and concerned individuals can do to manage and protect their local estuarine resources successfully. Much of the information presented here pertains to other embayments along the Maine coast…

Ruffing, Jenny

402

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

403

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...

404

Restaurant Growth in Lawrence, Kansas, 1950 to 2007  

E-print Network

. I would like to thank my parents, Doug and Bety Brackhan, for their support always. And finaly, many thanks and much love to my fianc?, John Young. Among many things, thank you for moving to Lawrence. v TABLE OF CONTENTS Abstract ii....6 Lawrence Restaurants, 1990 51 3.7 Lawrence Restaurants, 1990 Insets 52 3.8 Paradise Caf? 53 3.9 Herbivores 53 3.10 Yelo Sub 55 3.11 The Glas Onion 55 3.12 Lawrence Ethnic Restaurants, 1980 57 3.13 Lawrence Ethnic Restaurants, 1990 58 3.14 Applebee...

Brackhan, Jennifer L.

2009-01-22

405

Origin and composition of particulate organic matter in a macrotidal turbid estuary: The Gironde Estuary, France  

NASA Astrophysics Data System (ADS)

At the interface between continent and ocean, estuaries receive particles, and especially particulate organic matter (POM) originating from these two reservoirs, but also produce POM, through autochthonous primary production. The origin and composition of surface POM in the Gironde Estuary (SW France) and the environmental forcing of its variability was investigated using the data set produced by the French Coastal Monitoring Network SOMLIT (Service d'Observation en Milieu LITtoral; monthly like sampling during years 2007-2009). This estuary is considered as a model of macrotidal turbid estuaries. Using elemental and isotopic composition of the POM, we estimated that, at the inner estuary space scale and inter-annual time scale, surface particulate organic carbon (POC) was composed of terrestrial POM originated from the turbidity maximum (96.4%; refractory POC) and flood events (1.6%; labile and refractory POC), and of riverine (0.1%), estuarine (0.8%) and marine (1.1%) phytoplankton, i.e. that POC was 98% and 2% of terrestrial and phytoplankton origin, respectively. However, there was a clear spatial gradient: the phytoplankton contribution increases from ca. 1% in the upper and middle estuary to 8.5% in the lower estuary, where light condition is more favourable to plankton growth. The low contribution of phytoplankton to the POC is a characteristic of the Gironde estuary and contrast with other large temperate estuaries. Statistical analysis indicates that salinity, river flow and SPM concentration, and thus associated hydro-dynamic and sedimentary processes, were the only environmental forcings to the composition of surface POC in this system, at intra- and inter-annual time scale. In contrast, temperature and nutrient concentrations, and thus associated processes, do not force this composition of POC. By combining POC fluxes entering the inner estuary (literature data), POC loss as dissolved organic carbon and CO2 and as sediment trapping within the inner estuary (literature data), and our estimate of the composition of POC flux at the mouth of the estuary (96% and 4% of terrestrial and phytoplankton origin), a first-order net export of POC originating from the Gironde to the continental shelf was estimated: it amounts 48,150 tC yr-1, and is composed of 46,200 tC yr-1 of terrestrial material and of 1950 tC yr-1 of estuarine phytoplankton. POC exported by the Gironde Estuary is thus poorly bioavailable for shelf pelagic and benthic food webs.

Savoye, Nicolas; David, Valérie; Morisseau, François; Etcheber, Henri; Abril, Gwenaël; Billy, Isabelle; Charlier, Karine; Oggian, Georges; Derriennic, Hervé; Sautour, Benoît

2012-08-01

406

2020 Foresight Forging the Future of Lawrence Livermore National Laboratory  

SciTech Connect

The Lawrence Livermore National Laboratory (LLNL) of 2020 will look much different from the LLNL of today and vastly different from how it looked twenty years ago. We, the members of the Long-Range Strategy Project, envision a Laboratory not defined by one program--nuclear weapons research--but by several core programs related to or synergistic with LLNL's national security mission. We expect the Laboratory to be fully engaged with sponsors and the local community and closely partnering with other research and development (R&D) organizations and academia. Unclassified work will be a vital part of the Laboratory of 2020 and will visibly demonstrate LLNL's international science and technology strengths. We firmly believe that there will be a critical and continuing role for the Laboratory. As a dynamic and versatile multipurpose laboratory with a national security focus, LLNL will be applying its capabilities in science and technology to meet the needs of the nation in the 21st century. With strategic investments in science, outstanding technical capabilities, and effective relationships, the Laboratory will, we believe, continue to play a key role in securing the nation's future.

Chrzanowski, P.

2000-01-01

407

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...

408

Small estuaries: Ecology, environmental drivers and management challenges  

NASA Astrophysics Data System (ADS)

What is a 'small estuary'? Which environmental or anthropogenic factors rule these systems? What are the problems in managing small estuaries? In this special issue we collate current geomorphological, biogeochemical and ecological research on small estuaries, and we highlight managerial challenges and concerns.

Callaway, Ruth; Grenfell, Suzanne; Lønborg, Christian

2014-10-01

409

Monitoring and Managing Contamination in the San Francisco Estuary  

E-print Network

status of chemical contamination in the Estuary and efforts by environmental managers to reduce2000Update Monitoring and Managing Contamination in the San Francisco Estuary of the Estuary Pulse and prevent contamination problems. Most of the monitoring results in the report are a product of the San

410

MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL  

E-print Network

1 MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL NOAA Headquarters 1315 East National Fish and Wildlife Foundation - Mary Beth Charles Restore America's Estuaries ­ Diane Hoskins I (HTRW) and other issues. A member of the public (Diane Hoskins, Restore America's Estuaries) commented

US Army Corps of Engineers

411

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

412

Staff summary of Issues & Recommendations Ocean, Estuary and Plume  

E-print Network

1 Staff summary of Issues & Recommendations Ocean, Estuary and Plume *Preliminary draft, please strategies (31) V. Columbia River Estuary Strategies (32) VI. Mainstem Plan, D. Mainstem Strategies, Water River Estuary - The Council received many recommendations to continue and advance our endorsement

413

NAME: Port Susan Bay Estuary Restoration LOCATION: Snohomish County, Washington  

E-print Network

NAME: Port Susan Bay Estuary Restoration LOCATION: Snohomish County, Washington ACRES: 150 acres NON-FEDERAL SPONSOR: The Nature Conservancy (TNC) PROJECT DESCRIPTION: The Port Susan Bay Estuary farmland in the Stillaguamish River estuary in Puget Sound. In doing this, self sustaining native tidal

US Army Corps of Engineers

414

Polycyclic aromatic hydrocarbons in San Francisco Estuary sediments  

E-print Network

Polycyclic aromatic hydrocarbons in San Francisco Estuary sediments Daniel R. Oros*, John R.M. Ross San Francisco Estuary Institute, 7770 Pardee Lane, 2nd Floor, Oakland, CA 94621 USA Received 4 August of this study were to examine surface sediments in the San Francisco Estuary for PAH composition over a range

415

MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL  

E-print Network

1 MEETING SUMMARY OF THE ESTUARY HABITAT RESTORATION COUNCIL NOAA Headquarters 1315 East funded projects. A table providing a summary of the Status of Estuary Habitat Restoration Projects Chris Eng (FWS), a Work Group member, gave an overview of the estuary habitat restoration project

US Army Corps of Engineers

416

Salt dynamics of a highly unsteady estuary 1. Introduction  

E-print Network

18 CHAPTER II Salt dynamics of a highly unsteady estuary 1. Introduction This paper examines timescales. Willapa is a coastal-plain estuary connected to a highly active eastern boundary ocean in this estuary is on one level regional and ultimately ecological, while at the same time tied to a general

Hickey, Barbara

417

The Columbia River Estuary the Columbia River Basin  

E-print Network

The Columbia River Estuary and the Columbia River Basin Fish and Wildlife Program Independent Riddell November 28, 2000 ISAB 2000-5 #12;ISAB 2000-5 Estuary Report i EXECUTIVE SUMMARY The Northwest the impact of changes in the estuary relative to specific program or management actions taken in the upper

418

Volume II, Chapter 3 Columbia River Estuary Tributaries  

E-print Network

Volume II, Chapter 3 Columbia River Estuary Tributaries #12;TABLE OF CONTENTS 3.0 COLUMBIA RIVER ESTUARY TRIBUTARIES .................................................... 3-1 3.1 Subbasin Description....................................................................................................... 3-1 3.2.1 Chum--Columbia River Estuary Tributaries Subbasin....................................... 3

419

The Scheldt estuary: a description of a changing ecosystem  

Microsoft Academic Search

Estuaries are naturally highly dynamic and rapidly changing systems, forming a complex mixture of many different habitat types. They are very productive biomes and support many important ecosystem functions: biogeochemical cycling and movement of nutrients, mitigation of floods, maintenance of biodiversity and biological production. Human pressure on estuaries is very high. On the other hand, it is recognized that estuaries

Patrick Meire; Tom Ysebaert; Stefan Van Damme; Erika Van den Bergh; Tom Maris; Eric Struyf

2005-01-01

420

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

421

Environmental flow assessments for transformed estuaries  

NASA Astrophysics Data System (ADS)

Here, we propose an approach to environmental flow assessment that considers spatial pattern variations in potential habitats affected by river discharges and tidal currents in estuaries. The approach comprises four steps: identifying and simulating the distributions of critical environmental factors for habitats of typical species in an estuary; mapping of suitable habitats based on spatial distributions of the Habitat Suitability Index (HSI) and adopting the habitat aggregation index to understand fragmentation of potential suitable habitats; defining variations in water requirements for a certain species using trade-off analysis for different protection objectives; and recommending environmental flows in the estuary considering the compatibility and conflict of freshwater requirements for different species. This approach was tested using a case study in the Yellow River Estuary. Recommended environmental flows were determined by incorporating the requirements of four types of species into the assessments. Greater variability in freshwater inflows could be incorporated into the recommended environmental flows considering the adaptation of potential suitable habitats with variations in the flow regime. Environmental flow allocations should be conducted in conjunction with land use conflict management in estuaries. Based on the results presented here, the proposed approach offers flexible assessment of environmental flow for aquatic ecosystems that may be subject to future change.

Sun, Tao; Zhang, Heyue; Yang, Zhifeng; Yang, Wei

2015-01-01

422

Rapid barium removal in the Delaware estuary  

SciTech Connect

Six profiles of dissolved barium covering the entire salinity range of the Delaware River and Bay estuary from March through September 1996 were collected and analyzed. The profiles are similar to one another in both shape and magnitude except for one attribute. A sudden ({le} 24 days), nearly complete (>90%) removal of dissolved Ba in midestuary occurs in mid-May followed by an 80% recovery in early June. This removal appears to be temporally and spatially coupled to the end of the spring bloom. Based on such episodic behavior, and on recent work with flocculation of diatom exudates, the authors conclude that the Ba depletion is caused by barite precipitation in the estuary during the late stages of the bloom. This would imply that lower estuary and inner coastal margin sediments associated with eutrophic estuaries receive a seasonal pulse of barite. The suddenness of this event also implies that sedimentary barite is strongly influenced by high productivity events. Comparison of the riverine Ba concentration with the effective riverine end member after desorptive barium release yields an estimated 30--40 nM Ba available from the suspended sediments as they enter the estuary. This estimate is supported by excess barium in unfiltered samples over filtered samples taken from the river and also by calculations done elsewhere.

Stecher, H.A. III [Univ. of Delaware, Lewes, DE (United States). College of Marine Studies] [Univ. of Delaware, Lewes, DE (United States). College of Marine Studies; [Univ. of Delaware, Newark, DE (United States). Dept. of Geology; Kogut, M.B. [Univ. of Washington, Seattle, WA (United States). School of Oceanography] [Univ. of Washington, Seattle, WA (United States). School of Oceanography

1999-04-01

423

Lawrence Berkeley Laboratory 1993 Site Environmental Report  

SciTech Connect

This annual Site Environmental Report summarizes Lawrence Berkeley Laboratory`s (LBL`s) environmental activities in calendar year (CY) 1993. The purpose of this report is to characterize site environmental management performance, confirm compliance status with environmental standards and requirements, and highlight significant programs and efforts. Its format and content are consistent with the requirements of the US Department of Energy (DOE) Order 5400.1, General Environmental Protection Program.

Not Available

1994-05-01

424

Dr. Tom Lawrence: a life in chiropractic  

PubMed Central

He dwelt within the chiropractic orbit from the cradle to the grave. Second-generation chiropractor Tom Lawrence was a successful professional and family man who followed in his father’s footsteps and fought the good fight to improve chiropractic within his state and nation. His passing closes a chapter of living memory of the middle years of the first chiropractic century. PMID:17549212

Keating, Joseph C

2005-01-01

425

Radiographic testing at Lawrence Livermore National Laboratory  

SciTech Connect

Radiographic testing is a nondestructive inspection technique which uses penetrating radiation. The Nondestructive Evaluation (NDE) Section at Lawrence Livermore National Laboratory has a broad spectrum of equipment and techniques for radiographic testing. These resources include low-energy vacuum systems, low- and mid-energy cabinet and cell radiographic systems, high-energy linear accelerators, portable x-ray machines and radioisotopes for radiographic inspections. For diagnostic testing the NDE Section also has real-time and flash radiographic equipment.

Bossi, R.H.

1982-04-21

426

Life sciences: Lawrence Berkeley Laboratory, 1988  

SciTech Connect

Life Sciences Research at LBL has both a long history and a new visibility. The physics technologies pioneered in the days of Ernest O. Lawrence found almost immediate application in the medical research conducted by Ernest's brother, John Lawrence. And the tradition of nuclear medicine continues today, largely uninterrupted for more than 50 years. Until recently, though, life sciences research has been a secondary force at the Lawrence Berkeley Laboratory (LBL). Today, a true multi-program laboratory has emerged, in which the life sciences participate as a full partner. The LBL Human Genome Center is a contribution to the growing international effort to map the human genome. Its achievements represent LBL divisions, including Engineering, Materials and Chemical Sciences, and Information and Computing Sciences, along with Cell and Molecular Biology and Chemical Biodynamics. The Advanced Light Source Life Sciences Center will comprise not only beamlines and experimental end stations, but also supporting laboratories and office space for scientists from across the US. This effort reflects a confluence of scientific disciplines --- this time represented by individuals from the life sciences divisions and by engineers and physicists associated with the Advanced Light Source project. And finally, this report itself, the first summarizing the efforts of all four life sciences divisions, suggests a new spirit of cooperation. 30 figs.

Not Available

1989-07-01

427

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

428

Decadal mercury trends in San Francisco Estuary sediments.  

PubMed

Monitoring sediment quality and total mercury concentrations over the period 1993-2001 at 26 stations in San Francisco Estuary has shown the seasonal cycling of mercury sediment concentrations, as well as a significant (P < 0.05) decrease in those concentrations at eight stations across the estuary. This decrease in sediment mercury concentrations is attributed to the transport of relatively cleaner sediment to the estuary from the Sacramento River and San Joaquin River watersheds. Despite the decreases observed in some parts of the estuary, no corresponding trend has been found in concurrent studies on sport fish and bivalves in the estuary. PMID:17161835

Conaway, Christopher H; Ross, John R M; Looker, Richard; Mason, Robert P; Flegal, A Russell

2007-09-01

429

National Estuary Program after four years: A report to congress  

SciTech Connect

The National Estuary Program After Four Years: A Report to Congress is a status report on the National Estuary Program (NEP) and the seventeen Management Conferences that are part of the NEP. The Report is divided into: Part I Meeting a Need: The National Estuary Program; Part II Understanding Estuaries: The Key to Better Management; Part III Managing Estuaries: The Best Methods; Part IV Assessing the NEP: What Has Been Learned; Part V Looking to the Future: Trends and Needs; and Part VI Moving Ahead: The NEP Projects.

Not Available

1992-04-01

430

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

431

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

432

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

433

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.

1981-01-01

434

PECONIC ESTUARY: AN ASSESSMENT OF SHELLFISH RESOURCES IN THE TRIBUTARIES AND EMBAYMENTS OF THE PECONIC ESTUARY  

EPA Science Inventory

Executive Summary Historically, the Peconic Estuary's shellfish resources have supported significant fisheries for a number of species including hard clams, oysters and bay scallops. However, distribution and abundance data for the tributaries and embayments within the Peconic Es...

435

National estuary program guidance: Technical characterization in the National Estuary Program  

SciTech Connect

Estuaries are waterways, such as bays and sounds, where fresh water drained from the surrounding watershed mixes with salt water from the ocean. Section 320 of the Clean Water Act established the National Estuary Program (NEP) to identify nationally significant estuaries threatened by pollution, development, or overuse and to promote the preparation of comprehensive management plans to ensure their ecological integrity. The program's goals are protection and improvement of water quality and enhancement of living resources. To reach these goals, the Administrator of the U.S. Environmental Protection Agency (EPA) convenes management conferences for each estuary in the NEP to provide a forum for consensus building and problem solving among interested agencies and user groups.

Not Available

1994-06-01

436

Control of phytoplankton biomass in estuaries: A comparative analysis of microtidal and macrotidal estuaries  

Microsoft Academic Search

Macrotidal estuaries (mean tidal range >2m) generally exhibit a tolerance to pollution with nitrogen-containing nutrients\\u000a despite high loadings originating from freshwater outflows. These systems, which are characterized by high tidal energy, generally\\u000a exhibit lower levels of chlorophylla than systems with lower tidal energy. A comparative analysis of data from 40 microtidal and macrotidal estuaries shows that\\u000a mean annual chlorophylla levels

Yves Monbet

1992-01-01

437

Photo: TH DeWitt, USEPA EPA's benthic habitat data for Yaquina estuary  

E-print Network

Photo: TH DeWitt, USEPA EPA's benthic habitat data for Yaquina estuary Presented by Ted DeWitt Data & channel whole estuary or lower & mid estuary Bathymetry + topography 1998, 1999, 2000, 2002 various intertidal & subtidal whole estuary Wind-wave exposure (modelled) 2000? ? Intertidal whole estuary Intertidal

Wright, Dawn Jeannine

438

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

439

Micro network unburdens Lawrence Livermore's supercomputers  

SciTech Connect

Many program-development installations that rely on time-sharing systems are distributing some of the programming tasks to microcomputer networks. The Lawrence Livermore National Laboratory, for example, has installed several microcomputer local networks as front-ends to its massive Octopus network, composed of Cray-1 and Control Data Corp. 7600 mainframes. One local network, which incorporated terminals from different vendors, is used by the programming group for nuclear weapons simulation. It allows programmers to perform local text editing, which reduces the time necessary to retrieve, modify and verify code, and frees the central host for compilation and execution. It also facilitates job resubmission and user scheduling.

Cecil, A.

1983-03-01

440

Trace metal sources in two Malaysian estuaries  

SciTech Connect

The natural background concentrations of trace metals associated with suspended sediments in the non-urbanized upper reaches of the Kelang, Selangor, and Linggi rivers (West Malaysia) have been determined. These watersheds are underlain by weathered granite and covered, generally, by tropical jungle. The mean trace metal concentrations of the sediments in ..mu..-g/g are: Mn, 396; Zn, 92; Pb, 74; Cu, 24; Cr, 37; Ni, 21, and V, 45. These values are low compared to those reported from river sediments in North American and Europe. The spectra of trace metal abundances of the suspended sediments are very similar to the spectrum of source area granites. Thus, the granites impose a strong provenance control, in spite of intense weathering processes that have converted primary minerals to clay. Suspended sediments in the non-urbanized Selangor estuary have the same trace metal concentrations as above and exhibit no effects due to human activities. Suspended sediments in the Kelange estuary show Cu, Zn, and Pb concentrations of nearly three times the natural background levels and comparable to values reported from river sediments in North America and Europe. This estuary receives inputs from the urbanized area of Kuala Lumpur and the industrialized lower Kelang valley. Pb concentrations in the estuary are higher than for many northern hemisphere rivers. Furthermore, its concentration in the tributary sediments is higher than in the source area granites. This suggests airborne dispersal of Pb from the urban source and concentration in the suspended sediments.

Nelson, B.W.; Kahn, I.S.A.

1985-01-01

441

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.

442

Mercury pollution in the Ems estuary  

NASA Astrophysics Data System (ADS)

From approximately 1960 to 1975 the Ems estuary received several tons of mercury per year from a chlor-alkali plant, a pesticide factory and some minor sources. The discharge has been reduced drastically from 1976 onwards. In 1975 and 1976 measurements were made on the distribution of mercury in the sediment. The horizontal distribution revealed a strong local enrichment of the sediment near the point of discharge. The vertical distribution was found to be in accordance with the local deposition rates. In the water phase no significant change in mercury content from 1975 to 1978/79 could be demonstrated. In 1978/79 a difference between Ems estuary and Dutch Wadden Sea was not significant. In 1978 mercury contents of eelpout Zoarces viviparus in the Ems estuary were about twice as high as in the Wadden Sea. In the Ems estuary a decrease of these contents was found between 1974/75 and 1978. A similar decline in the Wadden Sea may be related to a decreased mercury discharge by the River Rhine.

Essink, K.

1980-03-01

443

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...

444

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,...

445

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 ...

446

TAMPA BAY ESTUARY PROGRAM, 2004 IMPLEMENTATION REVIEW  

EPA Science Inventory

The Tampa Bay Estuary Program and its partners have made measurable progress toward implementation of the adopted CCMP goals. Progress has occurred in the following areas: bay habitats, with an increase in seagrass, estuarine habitat restoration and preservation; water and sedime...

447

Restoration of the Golden Horn Estuary (Halic).  

PubMed

Restoration of the iconic Golden Horn Estuary in Istanbul, Turkey was a substantial political, logistical, ecological, and social challenge. Forty years of uncontrolled industrial and urban growth resulted in thick layers of anoxic sediment, toxic bacteria, strong hydrogen sulfide odor, and ecologically unlivable conditions. The major components of restoration, spanning two decades, have included (1) demolition and relocation of industries and homes along the shore, (2) creation of wastewater infrastructure, (3) removal of anoxic sludge from the estuary, (4) removal of a floating bridge that impeded circulation, and (5) creation of cultural and social facilities. Although Turkey is not known as an environmental leader in pollution control, the sum of these efforts was largely successful in revitalizing the area through dramatic water quality improvement. Consequently, the estuary is once again inhabitable for aquatic life as well as amenable to local resource users and foreign visitors, and Istanbul has regained a lost sense of cultural identity. This paper focuses on literature review and personal interviews to discuss the causes of degradation, solutions employed to rehabilitate the estuary, and subsequent physicochemical, ecological, and social changes. PMID:19781731

Coleman, Heather M; Kanat, Gurdal; Aydinol Turkdogan, F Ilter

2009-12-01

448

DELAWARE ESTUARY PROGRAM IMPLEMENTATION STREAMLINE REVIEW, 2002  

EPA Science Inventory

The primary purpose of the Delaware Estuary Program implementation review (formerly known as the biennial review) has been to assist EPA in. making funding decisions for those NEPs that are in the post-CCMP, or implementation, phase, and to evaluate implementation progress. The i...

449

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...

450

VOLUNTEER ESTUARY MONITORING: A METHOD MANUAL  

EPA Science Inventory

Executive Summary: This manual focuses on volunteer estuary monitoring. As concern over the well-being of the environment has increased during the past couple of decades, volunteer monitoring has become an integral part of the effort to assess the health of our nation’s wat...

451

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

452

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

453

Padilla Bay: The Estuary Guide. Level 2.  

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 middle school level is designed for use with the on-site program developed by the Padilla Bay National Esturine Research Reserve (Washington). The guide…

Friesem, Judy; Lynn, Valerie, Ed.

454

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.

455

A hybrid approach to estuary modelling  

Microsoft Academic Search

A hybrid model incorporating process and system modelling characteristics has been developed and applied to the evolution of a theoretical estuary with a small lake basin, partially enclosed by a barrier with an entrance open to the sea. The one-dimensional model is capable of modelling changes in sedimentation both spatially and temporally and hence, tracks changes in cross- section dimensions

O. Gould; J. Hinwood; E. McLean

456

A chemical survey of the Mississippi estuary  

SciTech Connect

A snap shot survey of the Mississippi estuary was made during a period of low river discharge, when the estuarine mixing zone was within the deltaic channels. Concentrations of H{sup +}, Ca{sup 2+}, inorganic phosphorus and inorganic carbon suggest that the waters of the river and the low salinity (<5%) portion of the estuary are near saturation with respect to calcite and sedimentary calcium phosphate. An input of oxidized nitrogen species and N{sub 2}O was observed in the estuary between O and 4{per thousand} salinity. The concentrations of dissolved NH{sub 4}{sup +} and O{sub 2}, over most of the estuary, appeared to be influenced by decomposition of terrestrial organic matter in bottom sediments. The estuarine bottom also appears to be a source of CH{sub 4} which has been suggested to originate from petroleum shipping and refining operations. Estuarine mixing with offshore Gulf waters was the dominant influence on distributions of dissolved species over most of the estuary (i.e., from salinities > 5%). The phytoplankton abundance (measured as chlorophyll a) increased as the depth of the mixed layer decreased in a manner consistent with the expected for a light-limited ecosystem. Fluxes of NO{sub 3}{sup {minus}} + NO{sub 2}{sup {minus}} and soluble inorganic phosphorus to the Gulf of Mexico were estimated to be 3.4 {plus minus} 0.2 {times} 10{sup 3} g N s{sup {minus}1} and 1.9 {plus minus} g P s{sup {minus}1}, respectively, at the time of this study.

Fox, L.E.; Lipschultz, R.; Kerkhof, L.; Wofsy, S.C. (Harvard Univ., Cambridge, MA (USA))

1987-03-01

457

St. John's Wort (image)  

MedlinePLUS

The herb St. John's Wort is believed to be helpful in relieving mild to moderate depression, but should only be taken under a physician's supervision. St. John's Wort may clash with other medications or foods ...

458

Signatures of Restoration and Management Changes in the Water Quality of a Central California Estuary  

E-print Network

In Advances in ecological research: Estuaries, 29, ed. D.B.Historical ecology of a central California estuary: 150Ecological signatures of anthropogenically altered tidal exchange in estua- rine ecosystems. Estuaries

Gee, Alison K.; Wasson, Kerstin; Shaw, Susan L.; Haskins, John

2010-01-01

459

33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.  

Code of Federal Regulations, 2013 CFR

...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. 165.1190 Section...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. (a) Location. ...zone: All navigable waters of the Oakland Estuary, California, from the surface to...

2013-07-01

460

78 FR 9887 - Proposed Information Collection; Comment Request; National Estuaries Restoration Inventory  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection; Comment Request; National Estuaries Restoration Inventory AGENCY: National...information collection. Collection of estuary habitat restoration project information...restoration project database mandated by the Estuary Restoration Act of 2000. The...

2013-02-12

461

33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.  

Code of Federal Regulations, 2014 CFR

...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. 165.1190 Section...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. (a) Location. ...zone: All navigable waters of the Oakland Estuary, California, from the surface to...

2014-07-01

462

33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.  

Code of Federal Regulations, 2012 CFR

...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. 165.1190 Section...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. (a) Location. ...zone: All navigable waters of the Oakland Estuary, California, from the surface to...

2012-07-01

463

San Francisco Estuary Regional Monitoring Program for Trace Substances Conceptual Framework and Rationale  

E-print Network

San Francisco Estuary Regional Monitoring Program for Trace Substances Conceptual Framework Anderson SFEI Contribution 317 November 2004 San Francisco Estuary Institute #12;Page 1 San Francisco Estuary Regional Monitoring Program for Trace Substances Conceptual Framework and Rationale

464

Geomorphologic and physical characteristics of a human impacted estuary: Quequén Grande River Estuary, Argentina  

NASA Astrophysics Data System (ADS)

Even though the Quequén Grande River Estuary has economic and strategic importance from an oceanographic point of view, it has been ignored until recently. Nevertheless, many anthropogenic modifications (i.e., dredging, jetty and harbour construction, etc.) have taken place in the last 100 years which, most of them, have resulted in significative economic expenses to the harbour and city authorities due to the lack of adequate prior studies. The purpose of this article is to provide a review of the present status of the geomorphology and main physical characteristics of the estuary and describe the effects of these man-made modifications upon the estuary. Data were gathered in several field cruises from 1994 to 2000 plus from continuous recording devices installed at or near the estuary directed to define the present geomorphologic and oceanographic conditions of the estuary and to establish a monitoring program. The ultimate goal is to provide some practical solutions in diminishing the maintenance of the harbour and to provide pollution-control devices. The estuary is classified as a microtidal, primary, coastal-plain system. It can be considered as a partly-mixed system 2 km from the mouth up to its head (15 km inland). Artificial dredging to accommodate the Quequén harbour in the last 2 km of the estuary has induced a highly stratified water column where the upper 2-3 m concentrates low salinity water and the lower layer is filled by water of the same or slightly higher salinity than the inner shelf waters. Due to the presence of a step at the head of the harbour, water circulation is very reduced and in some cases nonexistent, producing strong reductive and even anoxic conditions. The foot of the step is a sediment and organic matter trap that must be dredged periodically to insure adequate navigability.

Perillo, Gerardo M. E.; Pérez, Daniel E.; Piccolo, M. Cintia; Palma, Elbio D.; Cuadrado, Diana G.

2005-01-01

465

Historical changes in the Columbia River Estuary  

NASA Astrophysics Data System (ADS)

Historical changes in the hydrology, sedimentology, and physical oceanography of the Columbia River Estuary have been evaluated with a combination of statistical, cartographic, and numerical-modelling techniques. Comparison of data digitized from US Coast and Geodetic Survey bathymetric surveys conducted in the periods 1867-1875, 1926-1937, and 1949-1958 reveals that large changes in the morphology of the estuary have been caused by navigational improvements (jetties, dredged channels, and pile dikes) and by the diking and filling of much of the wetland area. Lesser changes are attributable to natural shoaling and erosion. There has been roughly a 15% decrease in tidal prism and a net accumulation of about 68 × 10 6m 3 of sediment in the estuary. Large volumes of sediment have been eroded from the entrance region and deposited on the continental shelf and in the balance of the estuary, contributing to formation of new land. The bathymetric data indicate that, ignoring erosion at the entrance, 370 to 485 × 10 6m 3 of sediment has been deposited in the estuary since 1868 at an average rate of about 0.5 cm y -1, roughly 5 times the rate at which sea level has fallen locally since the turn of the century. Riverflow data indicate that the seasonal flow cycle of the Columbia River has been significantly altered by regulation and diversion of water for irrigation. The greatest changes have occurred in the last thirty years. Flow variability over periods greater than a month has been significantly damped and the net discharge has been slightly reduced. These changes in riverflow are too recent to be reflected in the available in the available bathymetric data. Results from a laterally averaged, multiple-channel, two-dimensional numerical flow model (described in HAMILTON, 1990) suggest that the changes in morphology and riverflow have reduced mixing, increased stratification, altered the response to fortnightly (neap-spring) changes in tidal forcing, and decreased the salinity intrusion length and the transport of salt into the estuary. The overall effects of human intervention in the physical processes of the Columbia River Estuary (i.e. decrease in freshwater inflow, tidal prism, and mixing; increase in flushing time and fine sediment deposition, and net accumulation of sediment) are qualitatively similar to those observed in less energetic and more obviously altered estuarine systems. A concurrent reduction in wetland habitats has resulted in an estimated 82% reduction in emergent plant production and a 15% reduction in benthic macroalgae production, a combined production loss of 51,675 metric tons of organic carbon per year. This has been at least partially compensated by a large increase in the supply of riverine detritus derived from freshwater phytoplankton primary production. Comparison of modern and estimated preregulation organic carbon budgets for the estuary indicates a shift from a food web based on comparatively refractory macrodetritus derived from emergent vegetation to one involving more labile microdetritus derived from allochthonous phytoplankton. The shift has been driven by human-induced changes to the physical environment of the estuary. While this is a relatively comprehensive study of historical physical changes, it is incomplete in that the sediment budget is still uncertain. More precise quantification of the modern estuarine sediment budget will require both a better understanding of the fluvial input and dredging export terms and a sediment tranport model designed to explain historical changes in the sediment budget. Oceanographic studies to better determine the mechanisms leading to the formation of the turbidity maximum are also needed. The combination of cartography and modelling used in this study should be applicable in other systems where large changes in morphology have occurred in historical time.

Sherwood, Christopher R.; Jay, David A.; Bradford Harvey, R.; Hamilton, Peter; Simenstad, Charles A.

466

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

35 Years After the Clean Water Act A report published by the San Francisco Estuary Institute 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

467

San Francisco Estuary Institute Contribution No. 661 MONITORING RESULTSA Report of the Regional Monitoring Program for Water Quality in the San Francisco Estuary  

E-print Network

San Francisco Estuary Institute Contribution No. 661 RMP ANNUAL MONITORING RESULTSA Report of the Regional Monitoring Program for Water Quality in the San Francisco Estuary #12;THIS REPORT SHOULD BE CITED in the San Francisco Estuary (RMP). Contribution #661. San Francisco Estuary Institute, Richmond, CA. #12;RMP

468

Math 530: Topics in Geometry Winter Term, 2013, Lawrence University  

E-print Network

.corry@lawrence.edu Webpage: www.lawrence.edu/fast/corrys Texts: R. Hartshorne, Geometry: Euclid and Beyond (Springer) D. Densmore (ed.), Euclid's Elements (Green Lion Press) 1 Overview This course will be divided into three parts, each labeled by the name of a famous mathematician: Euclid, Hilbert, Poincar´e. 1.1 Euclid We

Corry, Scott

469

Parametrically Deformable Contour Models for Image Analysis Lawrence Hamilton Staib  

E-print Network

ABSTRACT Parametrically Deformable Contour Models for Image Analysis Lawrence Hamilton Staib Yale University 1990 Doctoral Dissertation Lawrence H. Staib Errata Page 20. In Equation 3.3, the numerators.10, v(t) should be v(t). Page 73. On the third line after Equation 5.18, "This method of adjusting

Duncan, James S.

470

Peng Xu and Philip Haves Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Peng Xu and Philip Haves Ernest Orlando Lawrence Berkeley National Laboratory HPCBS California Building Technologies Department Environmental Energy Technologies Division Ernest Orlando Lawrence Department, Environmental Energy Technologies Division Lawrence Berkeley National Laboratory Abstract

471

Satkartar Kinney and Mary Ann Piette Ernest Orlando Lawrence Berkeley National Laboratory  

E-print Network

Satkartar Kinney and Mary Ann Piette Ernest Orlando Lawrence Berkeley National Laboratory HPCBS Division Ernest Orlando Lawrence Berkeley National Laboratory University of California 1 Cyclotron Road Technologies Department, Environmental Energy Technologies Division Ernest Orlando Lawrence Berkeley National

472

Small estuary, big port - progress in the management of the Stour-Orwell Estuary system  

NASA Astrophysics Data System (ADS)

Management of port development is increasingly challenging because of the competitive requirement for deeper channels and because of the need to preserve important coastal wetlands which function as both habitat and flood defence. This paper describes the management of the Stour/Orwell Estuary system, Eastern England, an estuary system which has experienced considerable development and morphological change. The estuary is internationally important for its wetland bird populations and the intertidal areas of the estuary system are protected under European legislation. It is also the location of the Port of Felixstowe. In 1998/2000 the approach channel to the Port of Felixstowe was deepened from -12.5 mCD to -14.5 mCD. This paper describes the effects of the approach channel deepening, the approach taken to identifying the potential impact to intertidal habitat resulting from the deepening, the sediment recycling implemented as mitigation to prevent increased loss of habitat and the subsequent response of the estuary system to this intervention.

Spearman, Jeremy; Baugh, John; Feates, Nigel; Dearnaley, Mike; Eccles, Dan

2014-10-01

473

Benthic primary production in the Columbia River Estuary. Final report  

SciTech Connect

The general objective of the research associated with the Benthic Primary Production Work Unit of Columbia River Estuary Development Program was to determine mechanisms that control the production dynamics and species composition of benthic plant assemblages in the Columbia River Estuary. In particular, the work was concerned with effects of selected physical variables on structural and functional attributes of micro- and macro- vegetation, and on the productivity and biomass of benthic autotrophs on the tidal flats of the estuary.

McIntire, C.D.; Amspoker, M.C.

1984-02-01

474

Interactions between cockles, parasites and epibiota in the Avon-Heathcote Estuary, Christchurch, New Zealand.  

E-print Network

??Estuaries are productive ecological transition zones between freshwater and marine environments that provide important commercial, recreational, aesthetic and cultural resources. The Avon-Heathcote estuary in Christchurch,… (more)

Hildebrand, Thomas Michael

2014-01-01

475

Adaptive Optics at Lawrence Livermore National Laboratory  

SciTech Connect

Adaptive optics enables high resolution imaging through the atmospheric by correcting for the turbulent air's aberrations to the light waves passing through it. The Lawrence Livermore National Laboratory for a number of years has been at the forefront of applying adaptive optics technology to astronomy on the world's largest astronomical telescopes, in particular at the Keck 10-meter telescope on Mauna Kea, Hawaii. The technology includes the development of high-speed electrically driven deformable mirrors, high-speed low-noise CCD sensors, and real-time wavefront reconstruction and control hardware. Adaptive optics finds applications in many other areas where light beams pass through aberrating media and must be corrected to maintain diffraction-limited performance. We describe systems and results in astronomy, medicine (vision science), and horizontal path imaging, all active programs in our group.

Gavel, D T

2003-03-10

476

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

477

Lawrence Livermore plutonium button critical experiment benchmark  

SciTech Connect

The end of the Cold War and the subsequent weapons reductions have led to an increased need for the safe storage of large amounts of highly enriched plutonium. In support of code validation required to address this need, a set of critical experiments involving arrays of weapons-grade plutonium metal that were performed at the Lawrence Livermore National Laboratory (LLNL) in the late 1960s has been revisited. Although these experiments are well documented, discrepancies and omissions have been found in the earlier reports. Many of these have been resolved in the current work, and these data have been compiled into benchmark descriptions. In addition, a computational verification has been performed on the benchmarks using multiple computer codes. These benchmark descriptions are also being made available to the US Department of Energy (DOE)-sponsored Nuclear Criticality Safety Benchmark Evaluation Working Group for dissemination in the DOE Handbook on Evaluated Criticality Safety Benchmark Experiments.

Trumble, E.F.; Justice, J.B.; Frost, R.L.

1994-12-31

478

Cherry Ave. Sixth St. Garage  

E-print Network

Ave. E. Mabel St. E. Drachman St. E. Drachman St. E. Second St. E. First St. E. Second St. Hawthorne Campus Health Res. Life El Portal Disability Resource Center USB AHS Medical Library UMC East Garage. Individuals may use the lift on the vehicles. 2. Driver is required to assist with boarding and exiting

Arizona, University of

479

Carbon cycling in South-East Australian estuaries.  

E-print Network

??Our conceptual understanding of estuarine carbon cycling is based predominantly on northern hemisphere temperate systems which differ from south-east Australian estuaries in many ways. Further,… (more)

Maher, Damien Troy

2011-01-01

480

The Dynamics of a Partially Mixed Estuary  

Microsoft Academic Search

ABSTRACT Measurements of velocity, density, and pressure gradient in the lower Hudson River estuary were used to quantify the dominant,terms in the momentum,equation and to characterize their variations at tidal and spring? neap timescales. The vertical momentum,flux (assumed to be due mainly to turbulent shear stress) was estimated indirectly, based on the residual from the acceleration and pressure gradient terms.

W. Rockwell Geyer; John H. Trowbridge; Melissa M. Bowen

2000-01-01

481

Nutrient elements in large Chinese estuaries  

Microsoft Academic Search

Based on comprehensive observations since 1983, this study summarizes major features of nutrient elements (nitrogen, phosphorus and silicon) in large Chinese river\\/estuary systems. Elevated nutrient element levels were observed in Chinese rivers, when compared to large and less disturbed aquatic systems (e.g. the Amazon, Zaire and Orinoco). Data from this study are similar to those obtained from the polluted and\\/or

Jing Zhang

1996-01-01

482

Mercury biogeochemical cycling in a stratified estuary  

Microsoft Academic Search

Total Hg in the permanently stratified Pettaquamscutt estuary was <25 pM throughout the water column, even in highly sulfidic bottom waters. Particulate Hg was typically >40% of the total Hg. Reactive Hg (Hg[sub R]) was generally <3 pM and decreased with depth, but there is Hg[sub R] even in the anoxic bottom waters. Elemental Hg (Hg[sup 0]) was highest in

R. P. Mason; W. F. Fitzgerald; J. Hurley; A. K. Jr. Hanson; P. L. Donaghay; J. M. Sieburth

1993-01-01

483

Mercury biogeochemical cycling in a stratified estuary  

SciTech Connect

Total Hg in the permanently stratified Pettaquamscutt estuary was <25 pM throughout the water column, even in highly sulfidic bottom waters. Particulate Hg was typically >40% of the total Hg. Reactive Hg (Hg[sub R]) was generally <3 pM and decreased with depth, but there is Hg[sub R] even in the anoxic bottom waters. Elemental Hg (Hg[sup 0]) was highest in the mixed layer and below the detection limit at depth. Demethylation is not an important source of Hg[sup 0] in this estuary. Dimethylmercury was not detected. Monomethylmercury (MMHg) was near the detection limit in the mixed layer and increased rapidly in the low oxygen region. Dissolved MMHg correlated with bacteriochlorophyll pigments, suggesting that the microbial community plays an important role in MMHg production in the estuary. The overall distributions of dissolved and particulate Hg species result from the interaction with Fe and Mn redox cycling, particulate scavenging and sinking, and MMHg production in the pycnocline. The estimated rate of MMHg production from Hg[sub R] in the pycnocline region is 1.7% d[sup [minus]1]. Hg[sup 0] and MMHg are formed principally in the mixed layer and in the pycnocline region, respectively. Particulate scavenging is important, and sedimentation, methylation, and Hg[sup 0] production are the principal sinks for Hg[sub R].

Mason, R.P.; Fitzgerald, W.F. (Univ. of Connecticut, Groton, CT (United States)); Hurley, J. (Wisconsin DNR, Fitchburg, WI (United States)); Hanson, A.K. Jr.; Donaghay, P.L.; Sieburth, J.M. (Univ. of Rhode Island, Narragansett, RI (United States))

1993-09-01

484

Freshwater, tidal and wave influences on a small estuary  

NASA Astrophysics Data System (ADS)

Observations are presented of water levels, currents, salinity, turbidity, sediment grain sizes and sediment transport in the Devonshire Avon Estuary, UK, in order to improve knowledge of freshwater, wave and tidal influences on small, strongly tidal ría estuaries. A large reduction in tidal range occurred progressing from the coastal zone to the upper estuary that was mainly a consequence of rising bed and river water levels. The spring-neap cycle also had an influence on the reduction in tidal range along the length of the estuary. Surface gravity waves were completely dissipated propagating into the estuarine channel from the coastal zone, and despite strong wave-induced resuspension, suspended sediment was not transported into the lower estuary in observable amounts during the ensuing flood tide, indicating that the wave-suspended material was too coarse to remain in suspension once transported away from the surf zone. Turbidity in the lower estuary was relatively low during low runoff summer conditions and had largest values over low water, when turbid waters from farther up-estuary had been transported there. Strong resuspension events occurred at peak currents in the upper estuary during summer, reflecting the presence of finer-grained sediment sources. Turbidity was similar but greater in the lower estuary during high runoff winter conditions and strong resuspension occurred at peak currents, indicating an easily erodible, nearby sediment source, due to down-estuary movement and relocation of finer sediment over the winter. A large shoal in the lower estuary exhibited a consistent pattern of accretion/erosion during the high runoff months of late autumn and winter to spring that also was qualitatively consistent with sediment transport modelling and implied: (a), erosion from the up-estuary limit of the shoal with (b), down-estuary bed-load and suspended-load transport that accreted the centre and down-estuary limit of the shoal until (c), a diminished supply led to erosion via continued down-estuary transport from the shoal centre.

Uncles, R. J.; Stephens, J. A.; Harris, C.

2014-10-01

485

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

486

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

487

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-Hélène; Measures, Lena; L’Hérault, Vincent; Brêthes, Jean-Claude; Galbraith, Peter S.; Harvey, Michel; Lessard, Sylvie; Starr, Michel; Lecomte, Nicolas

2013-01-01

488

Mercury Partitioning in Surface Sediments of the Upper St. Lawrence River (Canada): Evidence of the Importance  

E-print Network

of the Importance of the Sulphur Chemistry João Canário & Laurier Poissant & Nelson O`Driscoll & Jeff Ridal & Tania Delongchamp & Martin Pilote & Philipe Constant & Jules Blais & David Lean Received: 4 May 2007 /Accepted: 11 :P. Constant Science and Technology Directorate, Environment Canada, Montreal, Québec, Canada N. O`Driscoll

O'Driscoll, Nelson

489

Shoreline retreat and coastal storms in the southern Gulf of St. Lawrence  

NASA Astrophysics Data System (ADS)

Submerged fluvial channels and estuarine facies seaward of the sandy North Shore of Prince Edward Island (Canada) attest to long-term mean relative sea-level rise >2.5 mm/a driving coastal retreat at mean rates >0.5 m/a over the past six thousand years. The shoreface, nearshore multiple bar complexes, and beaches are sand-limited and sand is transferred landward into multidecadal to century-scale storage in coastal dune and flood-tidal delta sinks. Stringent quality control of tide-gauge records for Charlottetown (PEI) indicates mean relative sea-level rise of 3.2 mm/a since 1911. When differenced from tidal predictions, this record provides a decadal sequence of storm surge occurrence for comparison with wind, wave hindcast, and sea-ice data for the southern Gulf over the past several decades. Soft photogrammetric digital rectification of vertical air photographs (1935, 1958, 1968, 1980/1981, 1990) and ground surveys (1989-2001) show large spatial and temporal variance in coastal recession rates, poorly correlated with the overall storm record, in part because of wave suppression by sea ice. Retreat of low sandstone-till cliffs at <1 m/a shows no statistically significant decadal variance. Other sites with shoreline retreat rates typically between 0.5 and 1.5 m/a show localized acceleration after 1980, reflecting a combination of storm impacts, morphodynamic change and sand loss to adjacent tidal inlets. Individual large storms cause localized rapid erosion, from which recovery depends in part on local sand supply. Some barrier shores with dunes show high longshore and interdecadal variance, and extensive multidecadal healing of former inlet and washover gaps. In some areas, at least, this reflects recovery from an episode of widespread washover predating the 1935 photography.

Forbes, D. L.; Parkes, G.; Manson, G. K.; Ketch, L.; Solomon, S. M.

2001-05-01

490

DISTRIBUTION AND TRANSFORMATION OF ELEMENTAL MERCURY IN THE ST. LAWRENCE RIVER AND LAKE ONTARIO. (R827915)  

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

491

137Cs and 210Po in Pacific Walrus and Bearded Seal from St. Lawrence Island, Alaska  

SciTech Connect

The activity concentration of Cesium-137 ({sup 137}Cs) and naturally-occurring Polonium-210 ({sup 210}Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea. The mean {sup 137}Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg{sup -1} (N= 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg{sup -1} (N=2, wet weight), respectively, in bearded seal. In general, {sup 137}Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, {sup 210}Po activity concentrations appear to be higher than those reported elsewhere but a larger variation. The mean {sup 210}Po concentration in the muscle tissue, liver and kidney of Pacific walrus (N=5, wet weight) were 28.7, 189, and 174 Bq kg{sup -1}, respectively. This compares with {sup 210}Po concentration values (N=2, wet weight) of 27, 207, and 68 Bq kg{sup -1} measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated bioaccumulation factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for {sup 210}Po that those of {sup 137}Cs. We conclude from radiological dose estimates that ingestion of {sup 137}Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessing health risks to Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic.

Hamilton, T F; Seagars, D J; Jokela, T; Layton, D

2005-02-02

492

137Cs and 210Po in Pacific walrus and bearded seal from St. Lawrence Island, Alaska.  

PubMed

The activity concentration of Cesium-137 ((137)Cs) and naturally-occurring Polonium-210 ((210)Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea during May 1996. The mean (137)Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg(-1) (n=5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg(-1) (n=2, wet weight), respectively, in bearded seal. In general, (137)Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, (210)Po activity concentrations are more variable and appear to be higher level compared with mammal data from other regions. The mean (210)Po concentration in the muscle tissue, liver and kidney of Pacific walrus (n=5, wet weight) were 28.7, 189, and 174 Bq kg(-1), respectively. This compares with (210)Po concentration values (n=2, wet weight) of 27, 207 and 68 Bq kg(-1) measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated concentration factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for (210)Po that those of (137)Cs. We conclude from radiological dose estimates that ingestion of (137)Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessment of risks of Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic. PMID:18371988

Hamilton, Terry; Seagars, Dana; Jokela, Terry; Layton, David

2008-06-01

493

Investigation of surface topography differences in native and exotic invertebrates in the St. Lawrence River.  

PubMed

The texture, or topography, interior of shells from native and exotic mollusks are measured and compared to determine if they can be discriminated. Area-scale fractal analysis is used to calculate relative areas as a function of scale, and the relative areas are used to evaluate the measurements. Measurements from a scanning laser profiler and from confocal and interferometric microscopes are compared, as are measurements of an original and a replica. The relative areas indicate clear differences between the measurement instruments. The largest relative areas are calculated from the confocal measurements. The trueness of the measurements has not been determined. However, the relative areas calculated from the confocal measurements are capable of discriminating the native clam from the exotic mussels with a confidence of greater than 99% at scales below 10?µm². PMID:20949618

Brown, D R S; Brown, C A

2010-01-01

494

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

495

77 FR 42642 - Safety Zone; City of Ogdensburg Fireworks, St. Lawrence River, Ogdensburg, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...Management, U.S. Coast Guard Sector Buffalo; telephone 716- 843-9343, email SectorBuffaloMarineSafety...Ogdensburg, NY. The Captain of the Port Buffalo has determined that fireworks launched...hazards in mind, the Captain of the Port Buffalo has determined that this temporary...

2012-07-20

496

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, lake