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1

Discriminating natal origin of spawning adult sea lamprey (Petromyzon marinus) in Lake Champlain using statolith elemental signatures  

E-print Network

Discriminating natal origin of spawning adult sea lamprey (Petromyzon marinus) in Lake Champlain Petromyzon marinus Statolith microchemistry Natal origin Lake Champlain Sea lamprey (Petromyzon marinus) is a nuisance species in the Great Lakes and Lake Champlain. Information about tributary contributions

Marsden, Ellen

2

Predictive Morphometric Relationships for Estimating Fecundity of Sea Lampreys from Lake Champlain and Other  

E-print Network

Predictive Morphometric Relationships for Estimating Fecundity of Sea Lampreys from Lake Champlain lampreys in Lake Champlain, we sampled 29 female sea lampreys (mean length ¼ 456 mm [range ¼ 364­550 mm based on wet weight alone. Sea lampreys Petromyzon marinus are a nuisance species in Lake Champlain

Marsden, Ellen

3

A life cycle approach to modeling sea lamprey population dynamics in the Lake Champlain basin to evaluate alternative control strategies  

E-print Network

A life cycle approach to modeling sea lamprey population dynamics in the Lake Champlain basin Population dynamics Lake Champlain Density dependence Fishery management Matrix modeling Sea lamprey (Petromyzon marinus) is a nuisance species in the Laurentian Great Lakes and Lake Champlain that has

Marsden, Ellen

4

Lake Champlain Maritime Museum  

NSDL National Science Digital Library

Located in the town of Vergennes, Vermont, the Lake Champlain Maritime Museum offers a lively interpretation of the maritime past and present in and around Lake Champlain. The materials on the site are divided into sections that include "Education", "Our Fleet", Shipwrecks & History", and "Ship's Store". The "Education" area is a good place to start, and it contains links to archived shipwreck webcasts and information for educators. Moving on, the "Shipwrecks & History" area features some of the Museum's Underwater Cultural Resources Survey Report and a brief narrative essay on the history of the Champlain Valley. Visitors with a scholarly bent may wish to check out the "Maritime Research Institute" area. Here they will find information about internships at the Institute and they can also read about the ongoing work at their conservation lab.

5

76 FR 12129 - Lake Champlain Sea Lamprey Control Alternatives Workgroup  

Federal Register 2010, 2011, 2012, 2013

...recommendations and advice on research and implementation of sea lamprey control techniques alternative to lampricide...be to discuss potential research initiatives that may enhance...alternative sea lamprey control techniques. The meeting is open...

2011-03-04

6

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

7

33 CFR 117.993 - Lake Champlain.  

...2014-07-01 2014-07-01 false Lake Champlain. 117.993 Section 117...Requirements Vermont 117.993 Lake Champlain. (a) The drawspan for...US2 Bridge, mile 91.8, over Lake Champlain, between South Hero Island...

2014-07-01

8

33 CFR 117.797 - Lake Champlain.  

...2014-07-01 2014-07-01 false Lake Champlain. 117.797 Section 117...Requirements New York 117.797 Lake Champlain. (a) The drawspan for...US2 Bridge, mile 91.8, over Lake Champlain, between South Hero Island...

2014-07-01

9

Predictive Morphometric Relationships for Estimating Fecundity of Sea Lampreys from Lake Champlain and Other Landlocked Populations  

Microsoft Academic Search

Landlocked populations of sea lamprey Petromyzon marinus are a nuisance in the Great Lakes and other lakes in the northeastern United States. In an effort to optimize control efforts, recent research has focused on creating population models to test various control scenarios. Accurate population parameters, such as fecundity, are an important component of these models. To determine the fecundity of

Stephen J. Smith; J. Ellen Marsden

2007-01-01

10

Technical Report No. 54 Updating the Lake Champlain  

E-print Network

Technical Report No. 54 Updating the Lake Champlain Basin Land Use Data to Improve Prediction for Lake Champlain Basin Program May 2007 PUBLICATION SERIES THIS PROGRAM IS SPONSORED BY U of Natural Resources Clean and Clear Action Plan funds through the Lake Champlain Basin Program. (General

Vermont, University of

11

NOAA Technical Memorandum GLERL-146 PROCEEDINGS OF NOAA LAKE CHAMPLAIN  

E-print Network

NOAA Technical Memorandum GLERL-146 PROCEEDINGS OF NOAA LAKE CHAMPLAIN PROGRAM REVIEW - OCTOBER 29;4 #12;5 Proceedings of NOAA Lake Champlain Program Review October 29-30 2008. G.L. Fahnenstiel, M.J. McCormick, and R. Artz 1.0 INTRODUCTION On October 29-30 2008, a formal review of NOAA's Lake Champlain Research

12

Lake Champlain Primary Investigator: Gary Fahnenstiel -NOAA GLERL  

E-print Network

Lake Champlain Primary Investigator: Gary Fahnenstiel - NOAA GLERL Co-Investigators: Mike McCormick Overview GLERL is participating in a large-scale multi-institutional program to study Lake Champlain: The Lake Champlain Research Consortium (LCRC), NOAA/GLERL and NOAA/ARL. GLERL's primary role has been

13

Strategic Plan for Lake Champlain Fisheries Miscellaneous Publication 2010-03  

E-print Network

Strategic Plan for Lake Champlain Fisheries Miscellaneous Publication 2010-03 #12;The Great Lakes Strickland Virginia West William W. Taylor October 2010 #12;Strategic Plan for Lake Champlain Fisheries J.......................................................................................................................... 2 DESCRIPTION OF LAKE CHAMPLAIN

Marsden, Ellen

14

Modeling the Atmospheric Deposition of Mercury to Lake Champlain  

E-print Network

Tributary and runoff water measurements Modeling the chemo- dynamics of the pollutant in the lake DataModeling the Atmospheric Deposition of Mercury to Lake Champlain (from Anthropogenic Sources at the Workshop on Coordination of Atmospheric Deposition Research in the Lake Champlain Basin June 5-6, 2003

15

33 CFR 110.136 - Lake Champlain, NY and VT.  

...Waters 1 2014-07-01 2014-07-01 false Lake Champlain, NY and VT. 110.136 Section 110.136 Navigation...ANCHORAGE REGULATIONS Anchorage Grounds 110.136 Lake Champlain, NY and VT. (a) Burlington Harbor, Vt....

2014-07-01

16

The reconstruction of the Lake Champlain sidewheel steamer Champlain II  

E-print Network

The steamship Champlain II, ex-Oakes Ames, was built as a railroad car transfer ferry in 1868 at Marks Bay, Burlington, Vermont in the private shipyard of Napoleon B. Proctor. The vessel was later converted to a passenger line boat in 1873...

Baldwin, Elizabeth Robinson

2012-06-07

17

A Comparison of Lake Trout Spawning, Fry Emergence, and Habitat Use in Lakes Michigan, Huron, and Champlain  

E-print Network

is underway in all of the Great Lakes and Lake Champlain, but restoration has only been achieved in Lake Huron, in Lake Michi- gan, and in Lake Champlain in 2000­2003. Divers surveyed and assessed abundance in Lake Michi- gan and Parry Sound, and very high at one site in Lake Champlain. Egg deposition was lowest

Marsden, Ellen

18

The history and future of Lake Champlain's fishes and fisheries J. Ellen Marsden a,  

E-print Network

The history and future of Lake Champlain's fishes and fisheries J. Ellen Marsden a, , Richard W, physical, chemical, and biological alterations of Lake Champlain have resulted in the loss of two species Lakes Research. Introduction Following the European discovery of Lake Champlain in 1609 by its namesake

Marsden, Ellen

19

Lake Champlain hydrodynamic monitoring program--An overview  

Microsoft Academic Search

The Vermont Waters Research Center (VWRC) sponsored Lake Champlain Hydrodynamic Monitoring Program began in June 1991 through a cooperative program between Middlebury College, Lamont-Doherty Geological Observatory of Columbia University, and the Great Lakes Environmental Research Laboratory. This pilot program was designed to lead into a multi-year study of the internal mechanics of lake circulation (such as the variability of internal

T. O. Manley; P. L. Manley; J. Saylor; K. L. Hunkins

1993-01-01

20

33 CFR 110.8 - Lake Champlain, N.Y. and Vt.  

...2014-07-01 2014-07-01 false Lake Champlain, N.Y. and Vt. 110.8...Anchorage Areas 110.8 Lake Champlain, N.Y. and Vt. (a) Ticonderoga...small cove at the westerly side of Lake Champlain, shoreward of a line...

2014-07-01

21

Mapping cyanobacterial blooms in Lake Champlain's Missisquoi Bay using QuickBird and MERIS satellite data  

E-print Network

Mapping cyanobacterial blooms in Lake Champlain's Missisquoi Bay using QuickBird and MERIS-a) concentrations for the eutrophic waters of Missisquoi Bay, Lake Champlain (VT­QC) were retrieved from Envisat. Missisquoi Bay on the Vermont­Québec border in northern Lake Champlain is typical of many such waters, where

Vincent, Warwick F.

22

Lake Champlain 2010: A summary of recent research and monitoring initiatives Douglas E. Facey a,  

E-print Network

Lake Champlain 2010: A summary of recent research and monitoring initiatives Douglas E. Facey a, Aiken Center, 81 Carrigan Dr., University of Vermont, Burlington, VT 05405, USA c Lake Champlain Research Institute, SUNY Plattsburgh, Plattsburgh, NY 12901, USA d Lake Champlain Basin Program, 54 West

Marsden, Ellen

23

Impacts of Projected Climate Change over the Lake Champlain Basin in Vermont  

E-print Network

Impacts of Projected Climate Change over the Lake Champlain Basin in Vermont JUSTIN GUILBERT November 2013, in final form 22 May 2014) ABSTRACT The Lake Champlain basin is a critical ecological the twenty-first century. 1. Introduction The Lake Champlain basin is a 21 326-km2 watershed on the U

Beckage, Brian

24

Movement of Sea Lamprey in the Lake Champlain Basin Eric A. Howe1, J. Ellen Marsden1,*, and Wayne Bouffard2  

E-print Network

degradation, and parasitism by sea lam- prey ultimately caused the extirpation of lake trout (Salvelinus namaycush) in Lakes Ontario, Erie, Huron, and Michigan; remnant populations sur- vived in Lake Superior

Marsden, Ellen

25

ERTS-1 imagery of the Lake Champlain region: A first look  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. First-look analysis of RBV imagery of Lake Champlain and adjacent areas provided the following information on land and water resources: (1) location and shape of islands over 200 meters at narrowest part; (2) location of manmade structures at least 10 meters across; (3) location of shoreline; (4) identification of algal blooms and major turbidity boundary; (5) identification of lake bottom features in sandy, shallow areas; (6) identification of major lake shore wetland and floodplain wetlands; (7) location of major streams; (8) identification of ice marginal deposits of major proportions and former shorelines of Champlain Sea; (9) identification of wooded areas, open land, and built-up areas.

Lind, A. O. (principal investigator); Henson, E. B.; Olson, J.; Wagner, W. P.

1972-01-01

26

Environmental study of ERTS-1 imagery: Lake Champlain and Vermont  

NASA Technical Reports Server (NTRS)

Environmental concerns of the State of Vermont currently being stressed include water quality in Lake Champlain and a state-wide land use and capability plan. Significant results obtained from ERTS-1 relate directly to the above concerns. Industrial water pollution and turbidity in Lake Champlain have been identified and mapped and the ERTS pollution data will be used in the developing court suit which Vermont has initiated against the polluters. ERTS imagery has also provided a foundation for updating and revising land use inventories. Major classes of land use have been identified and mapped, and substantial progress has been made toward the mapping of such land use divisions as crop and forest type, and wetlands.

Lind, A. O.; Henson, E. B.; Pelton, J. O.

1973-01-01

27

Mapping Cyanobacteria Blooms in Lake Champlain at Multiple ScaleMapping Cyanobacteria Blooms in Lake Champlain at Multiple Scales:s: QuickBirdQuickBird and MERIS Satellite Dataand MERIS Satellite Data  

E-print Network

Mapping Cyanobacteria Blooms in Lake Champlain at Multiple ScaleMapping Cyanobacteria Blooms in Lake Champlain at Multiple Scales:s: QuickBirdQuickBird and MERIS Satellite Dataand MERIS Satellite Data Harmful algal blooms in Lake Champlain (VT-NY-QC) are an increasingly serious concern. Such blooms

Morrissey, Leslie A.

28

Hydrodynamic Studies on Lake Champlain Primary Investigator(s): Gary Fahnenstiel -NOAA GLERL and Michael McCormick  

E-print Network

Hydrodynamic Studies on Lake Champlain Primary Investigator(s): Gary Fahnenstiel - NOAA GLERL studies have been underway on Lake Champlain since 1990 and is being expanded to include novel lagrangian of Lake Champlain have been very difficult to obtain using long- term Eulerian measurement techniques due

29

Pollution detection in Lake Champlain using ERTS-1 imagery  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. A major waste water discharge plume generated by a large paper mill along the New York shore of Lake Champlain was visually detected on ERTS-1 imagery. The plume is best displayed in 9.5 inch positive transparencies of MSS bands 4 and 5. Observation of the magnitude and extent of this plume is feasible, under magnification of 4 times. The chemical parameters of this plume have been documented by limnological studies. An enhancement technique useful for documenting the presence of waste water discharge plumes in Lake Champlain utilizes Polaroid MP-3 copy camera equipment and Spectral Data Corporation's multispectral viewer. The 9.5 inch, ERTS-1, positive transparency is enlarged using the Polaroid MP-3 copy camera to produce an enlarged lantern slide size positive transparency. These are projected through the multispectral viewer for enhancement and the scene is viewed directly on the screen or copied by an additional photographic step. The technique is simple and produces rapid results.

Lind, A. O. (principal investigator); Henson, E. B.

1972-01-01

30

Atmospheric mercury and trace metals in the Lake Champlain basin  

SciTech Connect

Atmospheric mercury in the Lake Champlain basin is currently being investigated by UMAQL and the Vermont Monitoring Cooperative to assess the magnitude, deposition and seasonal variation of atmospheric mercury in the region. Measurements of mercury in precipitation and in ambient air (vapor and particulate phase) have been conducted at the Proctor Maple Research Center in Underhill, VT since December, 1992. Precipitation samples were collected on a daily event basis, and analyzed for total mercury. Rain samples of sufficient volume were also filtered to determine the percent of total mercury in the dissolved phase. Samples were analyzed for mercury using cold vapor atomic fluorescence spectrometry. ICP-MS will also be used to quantify a number of other trace metals in the precipitation. Concentration ranges for mercury in the vapor phase, particulate phase and in precipitation for Under hill to date are 1.2--4.2 ng/m{sup 3}, 1--43 pg/m{sup 3} and 1.5--26 ng/L, respectively. Seasonal trends were evident, with higher concentrations in precipitation and greater wet deposition in the spring and summer months, whereas particulate mercury concentrations were elevated in winter months. Trace metal concentrations in particulates obtained from the NESCAUM network, in precipitation from ICP-MS analysis and meteorological associations will be used to investigate the sources of atmospheric mercury to the Lake Champlain basin.

Burke, J.M.; Rea, A.W.; Keeler, G.J. [Univ. of Michigan, Ann Arbor, MI (United States). Air Quality Lab.; Scherbatskoy, T. [Univ. of Vermont, Burlington, VT (United States)

1994-12-31

31

Pollution monitoring in Lake Champlain using ERTS-1 imagery  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Band 4 imagery of April 7 and 25 show contrasting pollution effects due to seasonal and discharge variations. The pollution plume emanating from the International Paper Co. mill just north of Fort Ticonderoga was first detected on October 10 ERTS-1 imagery and now has been documented during spring high lake level conditions. The plume was observed extending further to the north and east than under low water conditions of October 10. This northward extension reflects a stronger northward current flow expected in the turbid southern leg of Lake Champlain. The extensive plume of April 25 represents full plant operation while the April 5 scene shows some plume traces directly over the submerged diffuser, discharge pipe representing minimal discharge during weekend plant operation. The ERTS-1 documentation will be used in developing a model of plume behavior under varying environmental conditions and will hopefully serve to assist in a major resource decision pending at U.S. Supreme Court level.

Lind, A. O. (principal investigator); Henson, E. B.

1973-01-01

32

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

Microsoft Academic Search

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

Brandon Katz; Raymond G. Najjar; Thomas Cronin; John Rayburn; Michael E. Mann

2011-01-01

33

Astronauts Cooper and Conrad arrive aboard U.S.S. Lake Champlain  

NASA Technical Reports Server (NTRS)

A red-carpet welcome was staged for Astronauts L. Gordon Cooper Jr. and Charles Conrad Jr. as they arrive aboard the aircraft carrier U.S.S. Lake Champlain. They had been recovered from the Atlantic after the splashdown of their Gemini 5 spacecraft.

1965-01-01

34

Astronauts Conrad and Cooper slice cake on U.S.S. Lake Champlain  

NASA Technical Reports Server (NTRS)

Astronauts Charles Conrad Jr. (left) and L. Gordon Cooper Jr. prepate to slice into the huge cake prepared for them by the cooks onboard the aircraft carrier U.S.S. Lake Champlain. They are using ornamental Navy swords for knives.

1965-01-01

35

[Seltzer, N. and D.Wang. 2004. The importance of hydric soils and near-lake areas as phosphorus source areas in the Lake Champlain Basin: Evidence from a landscape-level model. pp. 143-158 IN  

E-print Network

source areas in the Lake Champlain Basin: Evidence from a landscape-level model. pp. 143-158 IN T.O. Manley, P.L. Manley, and T.B. Mihuc. (eds.) Lake Champlain: Partnerships and Research in the New AS PHOSPHORUS SOURCE AREAS IN THE LAKE CHAMPLAIN BASIN: EVIDENCE FROM A LANDSCAPE-LEVEL MODEL Nicole Seltzer

Vermont, University of

36

Environmental study of ERTS-1 imagery Lake Champlain Basin and Vermont  

NASA Technical Reports Server (NTRS)

The author has idenfified the following significant results. A first approximation land-type map using three categories of classification was generated for the Burlington area. The identification and mapping of a major turbidity front separating turbid waters of the southern arm of Lake Champlain from the clearer main water mass was reported on RBV 1 and 2 imagery and on subsequent MSS bands 4 and 5. Significant industrial pollution of Lake Champlain has degraded environmental quality in certain sections of the lake. Wetlands were detected and recognized using a combination of RBV bands 2 and 3. Using first-look RBV band 2 imagery, major ice marginal features were identified by using tonal patterns associated with vegetative cover. Major rivers were detected and recognized through the use of RBV band 3 imagery and MSS bands 6 and 7.

Lind, A. O. (principal investigator)

1972-01-01

37

Comparison of Larval Sea Lamprey Life History Characteristics in a Lampricide-Treated Tributary and Untreated Tributary  

E-print Network

and Untreated Tributary System of Lake Champlain ADAM ZERRENNER 1 AND J. ELLEN MARSDEN* Rubenstein School Abstract.--Control of sea lampreys Petromyzon marinus in Lake Champlain and the Laurentian Great Lakes to changes in age at transformation to prevent transformers from leaving Lake Champlain and Great Lakes

Marsden, Ellen

38

Accumulation of polychlorinated biphenyl congeners from Lake Champlain sediments by Mysis relicta  

SciTech Connect

Polychlorinated biphenyl (PCB) levels in lake trout (Salvelinus namaycush) from Lake Champlain often exceed the F.D.A. tolerance level of 2 [mu]g/g (wet weight). Of added concern are recent studies that suggest a relationship between the dioxin-like properties of non-ortho-substituted PCB congeners and impaired lake trout egg hatchability. Dietary accumulation of PCBs is thought to be an important exposure route for fish. The epibenthic freshwater shrimp Mysis relicta is an integral part of the benthic and pelagic food web in lake Champlain and may act as a link between PCBs in sediments and lake trout. Previous investigations have shown that diurnal migrations of mysids enhance the movement and distribution of toxic contaminants, effectively coupling the benthic and pelagic zones. The objective of this research was to examine the role contaminated sediments play in the transfer of PCBs to mysids. Bioaccumulation was assessed by exposing mysids to such sediments in two ways: (a) with organisms screened from sediments; and (b) with organisms in direct contact with sediments. Accumulation of PCBs over the course of the 24-day exposure period was examined on the following days: 0, 3, 6, 12, 21, and 24. Eighty-nine individual PCB congeners were measured in tissue and sediment. Mysids in direct contact with sediments accumulated significantly higher levels of PCBs than did organisms screened from sediments. Mysids accumulated substantial levels of PCBs, suggesting they may play an important part in the transfer of PCBs from sediments into the Lake Champlain food web. It is clear from this research that sediments can play a critical role in the accumulation of PCBs by mysids.

Lester, D.C.; McIntosh, A. (Univ. of Vermont, Burlington, VT (United States). Vermont Water Resources and Lake Studies Center)

1994-11-01

39

Factors Affecting Sea Lamprey Egg Survival STEPHEN J. SMITH  

E-print Network

is a nuisance parasitic fish in Lake Champlain that negatively affects important sport fish populations lamprey abundance (Marsden et al. 2003). Lake Champlain is 193 km long, has a maximum width of 19 km nontarget mortality in regularly treated tributaries. A population model of sea lampreys in Lake Champlain

Marsden, Ellen

40

Application of ERTS imagery to environmental studies of Lake Champlain  

NASA Technical Reports Server (NTRS)

ERTS Imagery has provided data relating to a number of environmental and limnological concerns such as water quality, lake flooding and lake ice formation. Pollution plume data provided by ERTS was recently used in the Supreme Court case involving the States of Vermont and New York and a paper company. Flooding of lowland tracts has been a major concern due to a repetitive pattern of high lake levels over the past three years, and ERTS imagery is being used to construct the first series of flood maps of the affected areas. Lake ice development and turbidity patterns have also been studied from ERTS, since these have significance for shore erosion studies.

Lind, A. O.

1974-01-01

41

SEA GRANT AT A GLANCE February 2014 National Sea Grant Office's  

E-print Network

:40pm � 11:10am Lake Champlain Sea Grant (Garber) #12;SEA GRANT AT A GLANCE � February 2014 3 11:10am at a glance USC Sea Grant at a glance TEXAS Sea Grant at a glance LAKE CHAMPLAIN Sea Grant at a glance

42

The R/V Folger a Floating Laboratory: Teaching Marine Science Skills on Lake Champlain (Invited)  

NASA Astrophysics Data System (ADS)

Undergraduate senior work has been required at Middlebury College as far back as 1960's and hands-on experiential learning was and still is the mode for our geology courses. The history of Middlebury College having a research vessel started in the 1970's when Dave Folger started the marine component of our curriculum and obtained the first Middlebury College's research vessel - a coast guard rescue surf boat (Bruno Schmidt). The second Middlebury College research vessel, the R/V Baldwin was purchased in 1985 and was used exclusively in a river-like setting due to its open cockpit and minimal research equipment. In 1990, Middlebury College received a grant from NSF-MRI to upgrade the vessel, to a then state-of the-art small oceanographic vessel including new equipment (CTD, side-scan sonar, ROV, met station, coring devices, computers and navigation). Middlebury College contributed monies to enclose the wheelhouse, install safer diesel engines, as well as a winch and an A-frame to haul in equipment. Over 600+ students used the Baldwin in a variety of geology courses; mainly Oceanography and Marine Geology. In 2010, Middlebury College received an NSF -ARRA grant (American Recovery and Reinvestment Act) to replace the ailing R/V Baldwin with a floating state-of-the art laboratory with the specific goals of increasing 1) access to lake research for Middlebury faculty and students in the biological, chemical, and environmental sciences, 2) the scope of lake research by reducing transit times over this 100km long lake, 3) stability for broad-lake research, 4) improve and expand research capabilities on Lake Champlain, 5) the carrying capacity (both equipment and people), and 6) instructional capability and overnight capabilities. The newly built R/V Folger is a sophisticated research vessel with advanced capabilities that provides a greater capacity to the research infrastructure on Lake Champlain, enhancing interdisciplinary inquiry not only for Middlebury College, but for other members of the local educational community for the next 30 to 50 years. The R/V Folger hosts significant amount of lab space allowing for on-vessel processing of real time data, enhanced navigational capabilities, smart classroom technology and new instrumentation such as multi-beam and CTD-rosette system. This all aluminum new research vessel, besides providing a new platform for Middlebury College's students, will also be used to enable faculty at other local colleges to provide experiential training in research techniques that would otherwise be unavailable; provide research training to local K-12 teachers; offer outreach to "land-locked" institutions and organizations within our tri-state region (NY, NH and VT); the development of a nautical archaeology program in the Lake Champlain basin; and produce data with environmental benefits to the region.

Manley, P.; Manley, T.

2013-12-01

43

Application of ERTS-1 imagery in the Vermont-New York dispute over pollution of Lake Champlain  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. ERTS-1 imagery and a composite map derived from ERTS-1 imagery were presented as evidence in a U.S. Supreme Court case involving the pollution of an interstate water body (Lake Champlain). A pollution problem generated by a large paper mill forms the basis of the suit (Vermont vs. International Paper Co. and State of New York) and ERTS-1 imagery shows the effluent pattern on the lake surface as extending into Vermont during three different times.

Lind, A. O. (principal investigator)

1973-01-01

44

New estimates of lethality of sea lamprey (Petromyzon marinus) attacks on lake trout (Salvelinus namaycush): Implications for fisheries management  

USGS Publications Warehouse

Sea lamprey (Petromyzon marinus) control in North America costs millions of dollars each year, and control measures are guided by assessment of lamprey-induced damage to fisheries. The favored prey of sea lamprey in freshwater ecosystems has been lake trout (Salvelinus namaycush). A key parameter in assessing sea lamprey damage, as well as managing lake trout fisheries, is the probability of an adult lake trout surviving a lamprey attack. The conventional value for this parameter has been 0.55, based on laboratory experiments. In contrast, based on catch curve analysis, mark-recapture techniques, and observed wounding rates, we estimated that adult lake trout in Lake Champlain have a 0.74 probability of surviving a lamprey attack. Although sea lamprey growth in Lake Champlain was lower than that observed in Lake Huron, application of an individual-based model to both lakes indicated that the probability of surviving an attack in Lake Champlain was only 1.1 times higher than that in Lake Huron. Thus, we estimated that lake trout survive a lamprey attack in Lake Huron with a probability of 0.66. Therefore, our results suggested that lethality of a sea lamprey attack on lake trout has been overestimated in previous model applications used in fisheries management. ?? 2008 NRC.

Madenjian, C. P.; Chipman, B. D.; Marsden, J. E.

2008-01-01

45

Application of the WHO alert level framework to cyanobacterial monitoring of Lake Champlain, Vermont.  

PubMed

The increasing incidence of toxic cyanobacteria blooms worldwide has created a need for practical and efficient monitoring in order to protect public health. We developed a monitoring and alert framework based on World Health Organization (WHO) recommendations and applied it on Lake Champlain during the summers of 2002-2004. The protocol began with collection of net samples of phytoplankton in order to maximize the chance of finding potential toxin-producing cyanobacteria. Samples were collected lake-wide in partnership with ongoing monitoring efforts, but because open water sample sites did not capture conditions along the shoreline, we added near-shore and shoreline stations in problem areas. Samples were examined qualitatively until potential toxin-producing taxa were found. Then quantitative analyses began, using a rapid screening method to estimate cell density based on colony size. A final cell density of 4000 cells/mL triggered toxin analyses. Primary analysis was for microcystins using ELISA methods. Cell densities, locations of colonies, and toxin concentrations were reported weekly to public health officials. We found that screening for potential toxin-producing cyanobacteria and then measuring toxin concentrations when cell densities reached critical levels worked well to identify problem locations. Although the WHO recommends using chlorophyll a concentration, it was not a good indicator of problem densities of potential toxin-producing cyanobacteria. Our cell density screening method missed no developing blooms but produced less precise density estimates at high cell counts. Overall, our framework appears to provide an efficient and effective method for monitoring cyanotoxin risks. PMID:16646001

Watzin, Mary C; Miller, Emily Brines; Shambaugh, Angela D; Kreider, Meghan A

2006-06-01

46

Carbon Cycling and the Coupling Between Proton and Electron Transfer Reactions in Aquatic Sediments in Lake Champlain  

Microsoft Academic Search

We used fine-scale porewater profiles and rate measurements together with a multiple component transportreaction model to\\u000a investigate carbon degradation pathways and the coupling between electron and proton transfer reactions in Lake Champlain\\u000a sediments. We measured porewater profiles of O2, Mn2+, Fe2+, HS?, pH and pCO2 at mm resolution by microelectrodes, and profiles of NO3\\u000a ?, SO4\\u000a 2?, NH4\\u000a +, total

Wei-Jun CaiGeorge; George W. Luther; Jeffrey C. Cornwell; Anne E. Giblin

2010-01-01

47

A leaky aquifer below Champlain Sea clay: closed-form solutions for natural seepage.  

PubMed

Closed-form solutions are proposed for natural seepage in semiconfined (leaky) aquifers such as those existing below the massive Champlain Sea clay layers in the Saint-Lawrence River Valley. The solutions are for an ideal horizontal leaky aquifer below an ideal aquitard that may have either a constant thickness and a constant hydraulic head at its surface, or a variable thickness and a variable hydraulic head at its surface. A few simplifying assumptions were needed to obtain the closed-form solutions. These have been verified using a finite element method, which did not make any of the assumptions but gave an excellent agreement for hydraulic heads and groundwater velocities. For example, the difference between the two solutions was smaller than 1 mm for variations in the 5 to 8 m range for the hydraulic head in the semiconfined aquifer. Note that fitting the hydraulic head data of monitoring wells to the theoretical solutions gives only the ratio of the aquifer and aquitard hydraulic conductivities, a clear case of multiple solutions for an inverse problem. Consequently, field permeability tests in the aquitard and the aquifer, and pumping tests in the aquifer, are still needed to determine the hydraulic conductivity values. PMID:23441962

Chapuis, Robert P; Saucier, Antoine

2013-01-01

48

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 Qubec 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

49

Assessing sediment quality in heterogeneous environments: A case study of a small urban harbor in Lake Champlain, Vermont, USA  

SciTech Connect

Relatively few case studies have been conducted demonstrating the utility of multiple endpoint approaches to sediment quality assessment in areas with moderate contaminant levels and heterogeneous conditions. Because variability is commonplace in natural systems, assessment approaches must be designed explicitly for these conditions. In an assessment of highly heterogeneous freshwater sediments in Lake Champlain, Vermont, USA, the authors measured multiple endpoints, including physical and chemical characteristics of the sediment, acute and chronic toxicity in three tests (Ceriodaphnia dubia, Chironomus tentans, and Pimephales promelas), and benthic community composition, at 19 sites throughout Inner Burlington Harbor. Multiple regression techniques were used to investigate whether significant relationships existed between biological endpoints and the physical and chemical characteristics of the sediments. Although all three laboratory exposures indicated toxicity at some sites, little correspondence was found among the tests. No changes in the benthic community could be attributed to trace contaminants. Multiple regression was useful in showing associations between contaminants, grain size, toxicity, and benthic community composition. Although not demonstrating causal linkages, these statistical analyses suggested which factors might be important in driving measured responses. In heterogeneous sites, an individualized assessment approach based on a preliminary analysis of variability might provide the most useful information.

Watzin, M.C.; McIntosh, A.W.; Brown, E.A.; Lacey, R.; Lester, D.C.; Newbrough, K.L.; Williams, A.R. [Univ. of Vermont, Burlington, VT (United States). School of Natural Resources

1997-10-01

50

Concentration and flux of total and dissolved phosphorus, total nitrogen, chloride, and total suspended solids for monitored tributaries of Lake Champlain, 1990-2012  

USGS Publications Warehouse

Annual and daily concentrations and fluxes of total and dissolved phosphorus, total nitrogen, chloride, and total suspended solids were estimated for 18 monitored tributaries to Lake Champlain by using the Weighted Regressions on Time, Discharge, and Seasons regression model. Estimates were made for 21 or 23 years, depending on data availability, for the purpose of providing timely and accessible summary reports as stipulated in the 2010 update to the Lake Champlain Opportunities for Action management plan. Estimates of concentration and flux were provided for each tributary based on (1) observed daily discharges and (2) a flow-normalizing procedure, which removed the random fluctuations of climate-related variability. The flux bias statistic, an indicator of the ability of the Weighted Regressions on Time, Discharge, and Season regression models to provide accurate representations of flux, showed acceptable bias (less than 10 percent) for 68 out of 72 models for total and dissolved phosphorus, total nitrogen, and chloride. Six out of 18 models for total suspended solids had moderate bias (between 10 and 30 percent), an expected result given the frequently nonlinear relation between total suspended solids and discharge. One model for total suspended solids with a very high bias was influenced by a single extreme value; however, removal of that value, although reducing the bias substantially, had little effect on annual fluxes.

Medalie, Laura

2014-01-01

51

Lake Champlain 1 exp 0 X 2 exp 0 NTMS Area New York, Vermont, and New Hampshire: Data Report (Abbreviated). National Uranium Resource Evaluation Program, Hydrogeochemical and Stream Sediment Reconnaissance.  

National Technical Information Service (NTIS)

This abbreviated data report presents results of ground water and stream sediment reconnaissance in the National Topographic Map Series (NTMS) Lake Champlain 1 exp 0 x 2 exp 0 quadrangle. Surface sediment samples were collected at 1196 sites. Ground-water...

J. R. Cook

1981-01-01

52

Sources of fine particulate species in ambient air over Lake Champlain Basin, VT  

SciTech Connect

This study is a part of an ongoing investigation of the types and locations of emission sources that contribute fine particulate air contaminants to Underhill, VT. The air quality monitoring data used for this study are from the Interagency Monitoring of Protected Visual Environments network for the period of 2001-2003 for the Underhill site. The main source-receptor modeling techniques used are the positive matrix factorization (PMF) and potential source contribution function (PSCF). This new study is intended as a comparison to a previous study of the 1988-1995 Underhill data that successfully revealed a total of 11 types of emission sources with significant contributions to this rural site. This new study has identified a total of nine sources: nitrate-rich secondary aerosol, wood smoke, East Coast oil combustion, automobile emission, metal working, soil/dust, sulfur-rich aerosol type I, sulfur-rich aerosol type II, and sea salt/road salt. Furthermore, the mass contributions from the PMF identified sources that correspond with sampling days with either good or poor visibility were analyzed to seek possible correlations. It has been shown that sulfur-rich aerosol type I, nitrate aerosol, and automobile emission are the most important contributors to visibility degradation. Soil/dust and sea salt/road salt also have an added effect. 38 refs., 17 figs., 2 tabs.

Ning Gao; Amy E. Gildemeister; Kira Krumhansl; Katherine Lafferty; Philip K. Hopke; Eugene Kim; Richard L. Poirot [St. Lawrence University, Canton, NY (United States)

2006-11-15

53

Erosion and channel change as factors of landslides and valley formation in Champlain Sea Clays: The Chacoura River, Quebec, Canada  

NASA Astrophysics Data System (ADS)

The Champlain Sea clays of Eastern Canada are incised by numerous rivers. Their slopes have been modified by landslides: on the Chacoura River near Trois-Rivires (Quebec), several large landslide scars, more or less recent, are visible. The role of erosion (channel incision, lateral channel migration and erosion of slopes due to agricultural drainage) as a trigger of these landslides is important. The aim of this study is to understand how erosion and landslides are related to valley development. From a detailed analysis of aerial photographs and DEMs, a map of the phenomena has been drawn by identifying various elements such as landslides, limits of the slope, position of the channel, and the area covered by forest. It is shown that channel change and erosion are strongly linked to landslides by the fact that they change the bank morphology in an unstable way. A slide in itself is a natural way for the slope to achieve stability. But when it occurs in a stream, it creates a disturbance to the stream flow enhancing local erosion which may change the river path and generate more erosion downstream or upstream resulting in more slides. Cross-valley sections and a longitudinal profile show that landslides are a major factor of valley formation. It appears that the upper part of the Chacoura River valley is still unaffected by landslides and has V-shaped sections. The lower part has been subject to intense erosion and many landslide scars can be seen. This shows that the valley morphology is transient, and that future activity is more likely to occur in the upper part of the river. Therefore the identification of areas prone to erosion will help determine the possible location of future large landslides just like the ones that occurred in the lower part.

Lvy, Sbastien; Jaboyedoff, Michel; Locat, Jacques; Demers, Denis

2012-04-01

54

Assessment of the spatial extent and height of flooding in Lake Champlain during May 2011, using satellite remote sensing and ground-based information  

USGS Publications Warehouse

Landsat 5 and moderate resolution imaging spectro-radiometer satellite imagery were used to map the area of inundation of Lake Champlain, which forms part of the border between New York and Vermont, during May 2011. During this month, the lakes water levels were record high values not observed in the previous 150 years. Lake inundation area determined from the satellite imagery is correlated with lake stage measured at three U.S. Geological Survey lake level gages to provide estimates of lake area at different lake levels (stage/area rating) and also compared with the levels of the high-water marks (HWMs) located on the Vermont side of the lake. The rating developed from the imagery shows a somewhat different relation than a similar stage/area rating developed from a medium-resolution digital elevation model (DEM) of the region. According to the rating derived from the imagery, the lake surface area during the peak lake level increased by about 17 percent above the average or normal lake level. By using a comparable rating developed from the DEM, the increase above average is estimated to be about 12 percent. The northern part of the lake (north of Burlington) showed the largest amount of flooding. Based on intersecting the inundation maps with the medium-resolution DEM, lake levels were not uniform around the lake. This is also evident from the lake level gage measurements and HWMs. The gage data indicate differences up to 0.5 feet between the northern and southern end of the lake. Additionally, the gage data show day-to-day and intradaily variation of the same range (0.5 foot). The high-water mark observations show differences up to 2 feet around the lake, with the highest level generally along the south- and west-facing shorelines. The data suggest that during most of May 2011, water levels were slightly higher and less variable in the northern part of the lake. These phenomena may be caused by wind effects as well as proximity to major river inputs to the lake. The inundation areas generated from the imagery generally coincide with flood mapping as estimated by the Federal Emergency Management Agency (FEMA) and shown on its digital flood insurance rate maps. Where areas in the flood inundation map derived from the imagery and the FEMA estimated flooded areas differ substantially, this difference may be due to differences between the flood magnitude at the time of the image and the assumed flood condition used for the FEMA modeling and mapping, wind/storage effects not accounted for by the FEMA modeling, and the resolution of the image compared to the DEM used in the FEMA mapping.

Bjerklie, David M.; Trombley, Thomas J.; Olson, Scott A.

2014-01-01

55

New York Landscape Regions in Google Earth: Champlain Lowlands  

NSDL National Science Digital Library

The Champlain Lowlands tour is part of the New York Landscape Regions Collection of Google Earth tours, created by a group of New York State science educators. This tour includes views of the gorge of the Ausable River, cut through Late Cambrian Potsdam Sandstone, and the geology of the Champlain Thrust Fault, a low angle thrust fault formed as the proto-Atlantic Ocean closed during the Taconic Oregeny. When it was still connected to the ocean, Lake Champlain was home to whales, whose fossils are now entombed in the lake sediments. The tour also includes classroom activities for students.

56

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

57

Ohio Sea Grant and Lake Erie Programs  

NSDL National Science Digital Library

The Ohio Sea Grant and Lake Erie Programs are housed at The Ohio State University, and are responsible for maintaining a number of scientific laboratories and research endeavors that focus primarily on Lake Erie. A number of their most valuable online resources are made available on their homepage, including the Lake Erie Information Discussion Board (where visitors can get answers to Lake Erie-related questions) and the Sea Grant's work in creating artificial reefs in Lake Erie. Moving on from there, the homepage also contains a site index, where visitors can learn about the diverse research projects currently underway and view some of their online publications. One particular publication, "Twine Line", is quite useful, as it is geared towards the general public and includes coverage about Lake Erie and Great Lakes issues and research.

58

A series of large, Late Wisconsinan meltwater floods through the Champlain and Hudson Valleys, New York State, USA  

NASA Astrophysics Data System (ADS)

The Champlain Valley in northeastern New York lies at the junction of two important Late Wisconsinan proglacial outflow routes, the Hudson Valley to the south and the St. Lawrence Valley to the northeast. Freshwater outflow from proglacial lakes in the Hudson/Champlain valleys (glacial lake Albany/Vermont) and the combined Ontario and St. Lawrence valleys (glacial Lake Iroquois) may have affected ocean circulation and thereby altered climate during the last deglaciation. We have estimated steady-state and three flood pulse discharges from these large meltwater reservoirs into the North Atlantic using channel geometry and a high resolution digital elevation model of the Late Wisconsinan paleogeography of the region. We estimate the steady-state meltwater discharge into the North Atlantic to be 0.3-0.6 Sv. The first flood event was a combined Iroquois/Vermont outflow at around 10,900 14C yr BP that released 700 km 3 of meltwater into the North Atlantic through the Hudson Valley with an estimated discharge of 1.1 Sv. A second outflow event released 2500 km 3 through the Hudson Valley shortly after the first event. Finally, approximately 1500 km 3 was released to the North Atlantic through the Gulf of St. Lawrence at the incursion of the Champlain Sea about 150-300 years later.

Rayburn, John A.; K. Knuepfer, Peter L.; Franzi, David A.

2005-11-01

59

Tidal Response of Titan's Lakes and Seas  

NASA Astrophysics Data System (ADS)

The Cassini spacecraft has revealed a vast set of lakes/seas filled or partially filled with liquid hydrocarbons and empty lake basins in the high latitudes of Titan. The seas and lakes of Titan provide an opportunity to explore an exciting aqueous environment whose characteristics are very different from what we know on Earth. The lakes appear in various shapes and sizes and are filled with liquid hydrocarbons, primarily methane and ethane. Recently, the Cassini spacecraft provided observations suggesting for the first time temporal variations in lake surfaces. The variation in the shorelines can be explained by different hypothesis including evaporation and tides. During Titan's 16 day orbital period around Saturn, the time-dependent tidal response of the lakes may affect the shorelines. Although the estimated tidal amplitudes by theoretical consideration yield smaller than the observed depth changes on Ontario Lacus, tides can have more significant effects of other lakes/seas with tidal amplitudes up to several meters. In the present study, besides Ontario Lacus we also consider Ligeia Mare, one of three large methane seas discovered by Cassini in the northern hemisphere of Titan and the target for the discovery mission of Titan Mare Explorer (TiME). The tidal response of Titan's lakes an seas are investigated by means of two- dimensional nonlinear shallow water equations The governing partial differential equations on the sphere are solved using SLIM (Second-generation Louvain- la- Neuve Ice-Ocean Model - http://www.climate.be/SLIM). SLIM is a hydrodynamical model based on finite element method. As all general circulation models, it uses primitive variables as prognostic quantities. Partial differential equations are discretized on curved surfaces using triangular meshes. The mesh is generated from recursive subdivisions of the faces of an icosahedron using GMSH software.. The code has a wetting-drying algorithm. The simulations can take into account several parameters such as the surface winds, viscosity, shoreline slopes and variable bathymetry.

Karatekin, O.; Demain, C.; Deleersnijder, E.

2011-12-01

60

Influence of Physical Processes on Fish Recruitment Variability in the Great Lakes  

E-print Network

, and Lake Champlain. For Lake Trout in Grand Traverse Bay, we will combine in-situ measures of temperature, and for Lake Trout in Lake Champlain. #12;For Lake Trout and Lake Whitefish in Thunder Bay Lake Huron, we Ruberg ReCON project) to predict spawning, egg incubation times, and fry emergence and dispersal. In Lake

61

Neutron activation analysis of sea-, lake-, and evaporated salt  

NASA Astrophysics Data System (ADS)

Salt is essential for human nutrition. Recently, it has become popular in Europe to rather use exotic sea salt or lake salt instead of purified evaporated salt, because of an alleged higher content of trace elements. In this study the content of trace elements and their bioavailability of 19 samples of different types of salt and 1 sample of brine purification sludge were investigated using instrumental neutron activation analysis. In general, sea-, lake-, and evaporated salt are quite pure. Trace elements determined in salt were Al, Br, Co, Cr, Cs, Fe, Rb, Sc, Sr, and Zn; some of them only in individual cases. It was found that, in general, the content of trace elements in sea- or lake salt was higher than in purified salt. Nevertheless, the use of sea- or lake salt does not contribute significantly to the human needs of essential trace elements, because their concentration in salt is too low or their compounds are not bioavailable.

Steinhauser, G.; Sterba, J. H.; Poljanc, K.; Bichler, M.; Buchtela, K.

2006-01-01

62

Mitochondrial DNA Analysis Indicates Sea Lampreys Are Indigenous to Lake Ontario  

Microsoft Academic Search

The parasitic sea lamprey Petromyzon marinus occurs throughout North America's Great Lakes, where it has an immense economic impact on commercially and recreationally important fishes. Sea lampreys indisputably invaded Lake Erie and the upper Great Lakes from Lake Ontario in the mid-1900s, but their official status as a nonnative species in Lake Ontario is based on circumstantial evidence and has

John R. Waldman; Cheryl Grunwald; Nirmal K. Roy; Isaac I. Wirgin

2004-01-01

63

Lake trout (Salvelinus namaycush) and sea lamprey (Petromyzon marinus) populations in Lake Michigan, 1971-78  

USGS Publications Warehouse

Lake trout (Salvelinus namaycush) was exterminated in Lake Michigan by the mid-1950s as a result of the combined effects of an intensive fishery and predation by the sea lamprey (Petromyzon marinus). The widespread application of lampricide in tributary streams had greatly reduced the abundance of lampreys by the early 1960s, and a program to restore self-sustaining populations of lake trout through stocking of yearlings and fingerlings was initiated in 1965. Although the hatchery-reared fish spawned widely in Lake Michigan each year after 1970, no progeny were observed except in an isolated area in Grand Traverse Bay. During 1971-78, sea lamprey abundance was generally greater in Wisconsin than in other parts of the lake. However, the rate of occurrence of sea lamprey wounds on lake trout dropped dramatically there in 1978 after the Peshtigo River, a tributary to Green Bay, was treated with lampricide. Application of Lake Michigan wounding rates to a regression model relating mortality to lamprey wounding developed from Lake Superior data, yielded lamprey-induced mortality estimates in 1977 of 5% in Michigan plus Indiana (combined) and 31% in Wisconsin; corresponding estimates for 1978 were 5 and 15%.

Wells, LaRue

1980-01-01

64

Selenium Accumulation in Sea Ducks Wintering at Lake Ontario  

Microsoft Academic Search

Numbers of wintering sea ducks, including buffleheads (Bucephala albeola; BUFF), common goldeneyes (Bucephala clangula; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after Dreissenid mussels (Dreissena bugensis and D. polymorpha) colonized the Great Lakes. Invertebrates, including Dreissenid mussels, are major diving duck prey items that can transfer\\u000a some trace elements, such as selenium (Se) to higher

Michael L. Schummer; Shannon S. Badzinski; Scott A. Petrie; Yu-Wei Chen; Nelson Belzile

2010-01-01

65

Predation by sea lamprey (Petromyzon marinus) on lake trout (Salvelinus namaycush) in southern Lake Ontario, 1982-1992  

USGS Publications Warehouse

Dead lake trout (Salvelinus namaycush) killed by sea lamprey (Petromyzon marinus) were collected from the bottom of Lake Ontario using bottom trawls. The number of dead lake trout per hectare could be predicted from the number of type A-1 sea lamprey marks observed on live fish in September gillnet surveys (r2 = 0.60, P P > 0.05) from those of live fish with A-1 marks in 5 of 6 years where comparisons could be made. Compared with Lake Superior strain lake trout, Seneca Lake strain fish were only 0.41 times as likely to be attacked by sea lamprey and were less likely to die from an attack (both differences P < 0.05). Conservative estimates of the numbers of lake trout killed by sea lamprey in southern Lake Ontario from October to mid-November ranged from 17 000 in 1988 to 121 000 in 1984.

Schneider, C. P.; Owens, R. W.; Bergstedt, R. A.; O'Gorman, R.

1996-01-01

66

The Dead Sea, The Lake and Its Setting  

NASA Astrophysics Data System (ADS)

I cannot think of a subject more befitting the description of interdisciplinary research with societal relevance than the study of the Dead Sea, a terminal lake of the Jordan River in Israel and Jordan. The scientific study of the Dead Sea is intimately connected with politics, religion, archeology, economic development, tourism, and environmental change.The Dead Sea is a relatively closed geologic and limnologic system with drastic physical changes often occurring on human timescales and with a long human history to observe these changes. Research in this unique area covers diverse aspects such as active subsidence and deformation along strike-slip faults; vertical stratification and stability of the water column; physical properties of extremely saline and dense (1234 kg/m3) water; spontaneous precipitation of minerals in an oversaturated environment; origin of the unusual chemical composition of the brine; existence of life in extreme environments; use of lake level fluctuations as a paleoclimatic indicator; and effects on the environment of human intervention versus natural climatic variability. Although the Dead Sea covers a small area on a global scale, it is nevertheless one of the largest natural laboratories for these types of research on Earth. These reasons make the Dead Sea a fascinating topic for the curious mind.

Brink, Uri ten

67

Small eddies observed in Lake Superior using SAR and sea surface temperature imagery  

E-print Network

transport processes is neces- sary to predict the fate of sediment, pollutants and invasive species in LakeSmall eddies observed in Lake Superior using SAR and sea surface temperature imagery Paul Mc Communicated by Leon Boegman Keywords: Great Lakes Lake Superior Remote sensing AVHRR SAR Making use

Matsumoto, Katsumi

68

Mercury accumulation in sea lamprey (Petromyzon marinus) from Lake Huron.  

PubMed

We determined whole-fish total mercury (Hg) concentrations of 40 male and 40 female adult sea lampreys (Petromyzon marinus) captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, bioenergetics modeling was used to explore the effects of sex-related differences in activity and resting (standard) metabolic rate (SMR) on mercury accumulation. The grand mean for Hg concentrations was 519 ng/g (standard error of the mean=46 ng/g). On average, males were 16% higher in Hg concentration than females. Bioenergetics modeling results indicated that 14% higher activity and SMR in males would account for this observed sex difference in Hg concentrations. We concluded that the higher Hg concentration in males was most likely due to higher rate of energy expenditure in males, stemming from greater activity and SMR. Our findings have implications for estimating the effects of sea lamprey populations on mercury cycling within ecosystems, as well as for the proposed opening of sea lamprey fisheries. Eventually, our results may prove useful in improving control of sea lamprey, a pest responsible for substantial damage to fisheries in lakes where it is not native. PMID:24275530

Madenjian, Charles P; Johnson, Nicholas S; Siefkes, Michael J; Dettmers, John M; Blum, Joel D; Johnson, Marcus W

2014-02-01

69

Reactivation of prethrusting, synconvergence normal faults as ramps within the Ordovician Champlain-Taconic thrust system  

Microsoft Academic Search

We present new geologic maps of the Lake Champlain region of west-central Vermont and east-central New York State. This region contains a shallow-crustal sec- tion of an Ordovician foreland basin and a far-traveled thrust system that transported the Upper Cambrian-Lower Ordovician platform-sequence, allochthonous rise- facies pelites and arenites and Middle Or- dovician basinal shales and flysch. Early foreland and shelf

Nicholas W. Hayman; W. S. F. Kidd

2002-01-01

70

Evaluating the growth potential of sea lampreys (Petromyzon marinus) feeding on siscowet lake trout (Salvelinus namaycush) in Lake Superior  

USGS Publications Warehouse

Differences in the preferred thermal habitat of Lake Superior lake trout morphotypes create alternative growth scenarios for parasitic sea lamprey (Petromyzon marinus) attached to lake trout hosts. Siscowet lake trout (Salvelinus namaycush) inhabit deep, consistently cold water (46 C) and are more abundant than lean lake trout (Salvelinus namaycush) which occupy temperatures between 8 and 12 C during summer thermal stratification. Using bioenergetics models we contrasted the growth potential of sea lampreys attached to siscowet and lean lake trout to determine how host temperature influences the growth and ultimate size of adult sea lamprey. Sea lampreys simulated under the thermal regime of siscowets are capable of reaching sizes within the range of adult sea lamprey sizes observed in Lake Superior tributaries. High lamprey wounding rates on siscowets suggest siscowets are important lamprey hosts. In addition, siscowets have higher survival rates from lamprey attacks than those observed for lean lake trout which raises the prospect that siscowets serve as a buffer to predation on more commercially desirable hosts such as lean lake trout, and could serve to subsidize lamprey growth.

Moody, E. K.; Weidel, B. C.; Ahrenstorff, T. D.; Mattes, W. P.; Kitchell, J. F.

2011-01-01

71

Selenium accumulation in sea ducks wintering at Lake Ontario.  

PubMed

Numbers of wintering sea ducks, including buffleheads (Bucephala albeola; BUFF), common goldeneyes (Bucephala clangula; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after Dreissenid mussels (Dreissena bugensis and D. polymorpha) colonized the Great Lakes. Invertebrates, including Dreissenid mussels, are major diving duck prey items that can transfer some trace elements, such as selenium (Se) to higher trophic levels. Se can be problematic for waterfowl and it often has been detected at elevated levels in organisms using the Great Lakes. There are, however, few data on hepatic Se concentrations in sea ducks, particularly during the winter at Lake Ontario. In this study, we evaluated interspecific differences and temporal trends in hepatic Se concentrations among BUFF (n = 77), COGO (n = 77), and LTDU (n = 79) wintering at Lake Ontario. All three species accumulated Se throughout winter, but COGO did so at a higher rate than did BUFF and LTDU. Overall, Se concentrations were higher in LTDU [mean = 22.7; 95% CI = 20.8-24.8 microg/g dry weight (dw)] than in BUFF ([mean = 12.3; 95% CI = 11.6-13.1 microg/g dw) and COGO ([mean = 12.0; 95% CI = 10.7-3.5 microg/g dw) throughout the winter. Se concentrations were deemed elevated (>33 microg/g dw) in 0%, 5%, and 19% of BUFF, COGO, and LTDU, respectively. Presently there are no data on Se toxicity end points for these species, so it is unclear how acquiring concentrations of these magnitudes affect their short- and long-term health or reproduction. PMID:19653029

Schummer, Michael L; Badzinski, Shannon S; Petrie, Scott A; Chen, Yu-Wei; Belzile, Nelson

2010-04-01

72

Selenium Accumulation in Sea Ducks Wintering at Lake Ontario Michael L. Schummer Shannon S. Badzinski  

E-print Network

; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after sea ducks, including buffleheads (Bucephala albeola; BUFF), common golden- eyes (Bucephala clangula

Belzile, Nelson

73

Sea lamprey abundance and management in Lake Superior, 1957 to 1999  

USGS Publications Warehouse

The international sea lamprey (Petromyzon marinus) control program successfully laid the foundation for rehabilitation of lake trout (Salvelinus namaycush) in Lake Superior and was well coordinated among management agencies during 1957-1999. The lampricide TFM was the primary control tool, with recurring treatments in 52 larval-producing streams. Barriers and sterile-male-release, as alternative control technologies, were significant elements of the program. Barriers blocked spawning sea lampreys from substantial areas of habitat for sea lamprey larvae during 1966-1999, and the sterile-male-release technique was used to reduce larval production during 1991-1996. Sea lamprey control resulted in the suppression of sea lamprey populations in Lake Superior, as evidenced by the linear decline in spawner abundance during 1962-1999. However, sea lamprey abundance was not as low as the targets specified in the fish community objectives. Most of the parasitic sea lampreys in Lake Superior probably originated from survivors of lampricide treatments. Self-sustaining populations of lake trout were restored in most of the lake by 1996, although many were killed annually by sea lampreys. Economic injury levels for damage to fish populations by sea lampreys are being developed and will be used to distribute sea lamprey control resources among the Great Lakes.

Heinrich, J. W.; Mullett, K. M.; Hansen, M. J.; Adams, J. V.; Klar, G. T.; Johnson, D. A.; Christie, G. C.; Young, R. J.

2003-01-01

74

Sea lamprey abundance and management in Lake Superior 1957-1999  

USGS Publications Warehouse

The international sea lamprey (Petromyzon marinus) control program successfully laid the foundation for rehabilitation of lake trout (Salvelinus namaycush) in Lake Superior and was well coordinated among management agencies during 1957-1999. The lampricide TFM was the primary control tool, with recurring treatments in 52 larval-producing streams. Barriers and sterile-male-release, as alternative control technologies, were significant elements of the program. Barriers blocked spawning sea lampreys from substantial areas of habitat for sea lamprey larvae during 1966-1999, and the sterile-male-release technique was used to reduce larval production during 1991-1996. Sea lamprey control resulted in the suppression of sea lamprey populations in Lake Superior, as evidenced by the linear decline in spawner abundance during 1962-1999. However, sea lamprey abundance was not as low as the targets specified in the fish community objectives. Most of the parasitic sea lampreys in Lake Superior probably originated from survivors of lampricide treatments. Self-sustaining populations of lake trout were restored in most of the lake by 1996, although many were killed annually by sea lampreys. Economic injury levels for damage to fish populations by sea lampreys are being developed and will be used to distribute sea lamprey control resources among the Great Lakes.

Heinrich, John W.; Mullett, Katherine M.; Hansen, Michael J.; Adams, Jean V.; Klar, Gerald T.; Johnson, David A.; Christie, Gavin C.; Young, Robert J.

2003-01-01

75

Simulating the water balance of the Aral Sea with a coupled regional climate-lake model  

Microsoft Academic Search

Before coupled atmosphere-lake models can be used to study the response of large lake systems to climatic forcings, we must first evaluate how well they simulate the water balance and associated lake atmosphere interactions under present-day conditions. We evaluate the hydrology simulated by a lake model coupled to NCAR's regional climate model (RegCM2) in a study of the Aral Sea.

Eric E. Small; Lisa Cirbus Sloan; Steven Hostetler; Filippo Giorgi

1999-01-01

76

Recommendations for Assessing Sea Lamprey Damages: Toward Optimizing the Control Program in the Great Lakes  

Microsoft Academic Search

The Great Lakes sea lamprey (Petromyzon marinus) control program currently allocates stream treatments to optimize the number of juvenile sea lampreys killed for a given level of control. Although the economic benefits derived from control appear to outweigh the dollars spent on control efforts, optimizing the number of sea lampreys killed will not necessarily optimize the economic benefits provided by

Thomas J. Stewart; James R. Bence; Roger A. Bergstedt; Mark P. Ebener; Frank Lupi; Michael A. Rutter

2003-01-01

77

Marsden p. 1 J. ELLEN MARSDEN  

E-print Network

pre-proposal. . Lake Champlain Sea Lamprey Alternatives Workgroup $100,000 2011-2013. Marsden, J. E among basins in Lake Champlain. State Wildlife Incentives Grant, VTDFW, $39,688 2012-2013 Lochet, A., B lamprey in Lake Champlain using recent advances in statolith microchemistry. Lake Champlain Sea Lamprey

Marsden, Ellen

78

Changes in the lake trout population of southern Lake Superior in relation to the fishery, the sea lamprey, and stocking, 1950-70  

USGS Publications Warehouse

Reduction of sea lamprey abundance resulted in an immediate increase in survival and abundance of lake trout, especially of the larger sizes. As abundance of lake trout progressively increased in 1962-70, survival of the smaller legal-size lake trout increased, probably due to reduction of the predator-prey ratio and an increase in availability of larger lake trout preferred by sea lampreys. Abundance of spawning-size lake trout was limited by high natural mortality in 1965-70. Circumstantial evidence suggested that sea lamprey predation contributed a major part of the high natural mortality.

Pycha, Richard L.; King, George R.

1975-01-01

79

The late Quaternary limnological history of Lake Kinneret (Sea of Galilee), Israel  

E-print Network

The late Quaternary limnological history of Lake Kinneret (Sea of Galilee), Israel N. Hazana , M) during the Neogene­Quartenary periods. We reconstructed the limnological history (level and composition

Marco, Shmuel "Shmulik"

80

Wind Fields over the Great Lakes Measured by the SeaWinds Scatterometer on the QuikSCAT Satellite  

E-print Network

Wind Fields over the Great Lakes Measured by the SeaWinds Scatterometer on the QuikSCAT Satellite and Atmospheric Administration Great Lakes Environmental Research Laboratory 2205 Commonwealth Blvd. Ann Arbor for wind retrieval over the Great Lakes on a daily basis. We use data acquired by the Sea

81

Survival of Rainbow Trout and Lake Trout after Sea Lamprey Attack  

Microsoft Academic Search

Survival was significantly higher (P = 0.054) for rainbow trout Oncorhynchus mykiss (formerly Salmo gairdneri) than for lake trout Salvelinus namaycush when the fish were subjected in the laboratory to a single attack by a sea lamprey Petromyzon marinus. Of 77 rainbow trout, 40% died (35% by direct attack and 5% by secondary infection) and 60% survived; of 77 lake

William D. Swink; Lee H. Hanson

1989-01-01

82

Simulating the water balance of the Aral Sea with a coupled regional climate-lake model  

USGS Publications Warehouse

Before coupled atmosphere-lake models can be used to study the response of large lake systems to climatic forcings, we must first evaluate how well they simulate the water balance and associated lake atmosphere interactions under present-day conditions. We evaluate the hydrology simulated by a lake model coupled to NCAR's regional climate model (RegCM2) in a study of the Aral Sea. The meteorological variables that are input to the lake model are simulated well by RegCM2. Simulated surface air temperatures closely match observed values, except during spring and fall when the simulated temperatures are too cold. The magnitude of precipitation is too high in the region surrounding the Aral Sea during summer and fall. On a yearly basis, RegCM2 produces a reasonable amount of runoff throughout the drainage basin. The lake model coupled to RegCM2 accurately simulates Aral Sea surface temperatures (SSTs). The lake model also simulates observed mid-winter ice fraction well, although the onset of ice growth occurs too late in the year and the ice melts too rapidly in the spring. The simulated annual evaporation from the Aral Sea is consistent with observed estimates; however, the simulated evaporation is greater than observed during summer and less than observed during winter. In a "stand-alone" lake model simulation, the simulated Aral Sea hydrology does not match observations as closely as in the coupled model experiment. These results suggest that a stand-alone lake model would not accurately simulate the hydrologic response of the Aral Sea to various forcings. Copyright 1999 by the American Geophysical Union.

Small, E.E.; Sloan, L.C.; Hostetler, S.; Giorgi, F.

1999-01-01

83

Sea Lamprey Abundance and Management in Lake Superior, 1957 to 1999  

Microsoft Academic Search

The international sea lamprey (Petromyzon marinus) control program successfully laid the foundation for rehabilitation of lake trout (Salvelinus namaycush) in Lake Superior and was well coordinated among management agencies during 19571999. The lampricide TFM was the primary control tool, with recurring treatments in 52 larval-producing streams. Barriers and sterile-male-release, as alternative control technologies, were significant elements of the program. Barriers

John W. Heinrich; Katherine M. Mullett; Michael J. Hansen; Jean V. Adams; Gerald T. Klar; David A. Johnson; Gavin C. Christie; Robert J. Young

2003-01-01

84

J. Great Lakes Res. 34:721730 Internat. Assoc. Great Lakes Res., 2008  

E-print Network

extensive mea- surements of the subsurface current and thermal #12;722 McCormick et al. structure have been region of Lake Champlain. Even fewer observations of the surface currents exist. McCormick et al. (2006J. Great Lakes Res. 34:721­730 Internat. Assoc. Great Lakes Res., 2008 Tracking the Surface Flow

85

Lake Baikal in southeastern Siberia,the "Sacred Sea,"incites strong emotions and action in Russia. In March 2006,  

E-print Network

Articles Lake Baikal in southeastern Siberia,the "Sacred Sea,"incites strong emotions and action pipeline scheduled to pass within 800 me- ters (m) of Lake Baikal's shoreline, and, within days, President Putin announced the pipeline would be rerouted outside the lake's watershed (Cullison 2007).In July 2007

Dever, Jennifer A.

86

Effect of water temperature on sea lamprey growth and lake trout survival  

SciTech Connect

Percent mortality of lake trout Salvelinus namaycush subjected to single sea lamprey Petromyzon marinus attacks did not differ significantly between lower-temperature (mortality = 54%; temperature [le] 10[degrees]C; N = 33) and higher-temperature (mortality = 69%; temperature = 12.8-14.4[degrees]C; N = 45) laboratory studies conducted from 1 June to 28 November 1989. However, sea lampreys fed longer and killed fewer fish in colder water (mean attachment 467.0 h; 18 fish killed) than in warmer water (mean attachment 161.7 h; 31 fish killed), probably because food consumption was lower in colder water. These results indicate that the number of fish killed by sea lampreys could be much greater in warmer water and that temperature must be considered when fish losses from sea lamprey attacks are estimated. Previous studies (Swink and Hanson 1989; Swink 1990) of the effects of single sea lamprey Petromyzon marinus attacks on lake trout Salvelinus namaycush showed significantly less lake trout mortality at temperatures of 10[degrees]C and lower than at higher temperatures. The reduced host mortality, however, could not be attributed solely to lower temperature because warmwater and coldwater attacks occurred during different seasons. In those studies, the author was unable to hold water temperature at 10[degrees]C or less in late summer and early fall, when most fish are killed by sea lampreys in the Great Lakes (Christie and Kolenosky 1980; Bergstedt and Schneider 1988). Modifications to the fish holding facilities at the Hammond Bay Biological Station in 1988 allowed maintenance of a limited amount of water at 10[degrees]C or less throughout the year. Hence, the objective of this study was to compare sea lamprey-induced mortality of lake trout at 10[degrees]C or less with that at 12.8-14.4[degrees]C during the normal feeding season (June through November). 15 refs., 1 fig., 1 tab.

Swink, W.D. (Hammond Bay Biological Station, Millersburg, MI (United States))

1993-11-01

87

Effects of nonlethal sea lamprey attack on the blood chemistry of lake trout  

USGS Publications Warehouse

A laboratory study examined changes in the blood chemistry of field-caught and hatchery-reared lake trout Salvelinus namaycush subjected to a nonlethal attack by sea lampreys Petromyzon marinus. We measured glucose, total protein, amylase, alkaline phosphatase (ALKP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase, calcium, magnesium, triglycerides, sodium, and potassium with a Kodak Ektachem DT60 Analyzer, Ektachem DTSC Module, and the DTE Module. Mean levels of total protein, AST, ALKP, hematocrit, calcium, magnesium, and sodium decreased significantly (Pa?? 0.05), and mean levels of ALT and potassium increased significantly (Pa?? 0.05) after sea lamprey feeding. Lake trout condition (K) and hematocrit levels also decreased significantly (Pa?? 0.05) after the sea lamprey attack. Frequency distributions of eight lake trout blood chemistry variables and the hematocrit were significantly different before and after a sea lamprey attack. A second study that used hatchery lake trout broodstock measured changes in hematocrit before and after a sea lamprey attack.

Edsall, Carol Cotant; Swink, William D.

2001-01-01

88

Sea Lamprey ( Petromyzon marinus) Parasite-host Interactions in the Great Lakes  

Microsoft Academic Search

Prediction of how host mortality responds to efforts to control sea lampreys (Petromyzon marinus) is central to the integrated management strategy for sea lamprey (IMSL) in the Great Lakes. A parasite-host submodel is used as part of this strategy, and this includes a type-2 multi-species functional response, a developmental response, but no numerical response. General patterns of host species and

James R. Bence; Roger A. Bergstedt; Gavin C. Christie; Phillip A. Cochran; Mark P. Ebener; Joseph F. Koonce; Michael A. Rutter; William D. Swink

2003-01-01

89

Statolith microchemistry as a technique for discriminating among Great Lakes sea lamprey ( Petromyzon marinus ) spawning tributaries  

Microsoft Academic Search

Laurentian Great Lakes fishery management agencies are seeking ways to identify natal origins of parasitic- and spawning-phase sea lamprey (Petromyzon marinus) so that efforts to control this invasive species can be prioritized. We developed laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) as a technique to quantify elemental concentrations in larval sea lamprey statoliths and explored the use of statolith microchemistry

Carrol P. Hand; Stuart A. Ludsin; Brian J. Fryer; J. Ellen Marsden

2008-01-01

90

Tectonic tilt rates derived from lake-level measurements, Salton Sea, California  

USGS Publications Warehouse

Tectonic tilt at the Salton Sea was calculated by differencing lake-level measurements from two points on the sea. During the past 26 years, tilting was down toward the southeast. By 1970 differential vertical movement amounted to 110 millimeters between two gages situated 38 kilometers apart on the southwest shore. A reversal in tilt direction in late 1972 has diminished the net differential vertical movement to 60 millimeters. Copyright ?? 1980 AAAS.

Wilson, M.E.; Wood, S.H.

1980-01-01

91

Tectonic tilt rates derived from lake-level measurements, Salton Sea, California  

SciTech Connect

Tectonic tilt at the Salton Sea was calculated by differencing lake-level measurements from two points on the sea. During the past 26 years, tilting was down toward the southeast. By 1970 differential vertical movement amounted to 110 millimeters between two gages situated 38 kilometers apart on the southwest shore. A reversal in tilt direction in late 1972 has diminished the net differential vertical movement to 60 millimeters.

Wilson, M.E. (Geological Survey, Menlo Park, CA); Wood, S.H.

1980-01-11

92

Sea lamprey (Petromyzon marinus) parasite-host interactions in the Great Lakes  

USGS Publications Warehouse

Prediction of how host mortality responds to efforts to control sea lampreys (Petromyzon marinus) is central to the integrated management strategy for sea lamprey (IMSL) in the Great Lakes. A parasite-host submodel is used as part of this strategy, and this includes a type-2 multi-species functional response, a developmental response, but no numerical response. General patterns of host species and size selection are consistent with the model assumptions, but some observations appear to diverge. For example, some patterns in sea lamprey marking on hosts suggest increases in selectivity for less preferred hosts and lower host survival when preferred hosts are scarce. Nevertheless, many of the IMSL assumptions may be adequate under conditions targeted by fish community objectives. Of great concern is the possibility that the survival of young parasites (parasitic-phase sea lampreys) varies substantially among lakes or over time. Joint analysis of abundance estimates for parasites being produced in streams and returning spawners could address this. Data on sea lamprey marks is a critical source of information on sea lamprey activity and potential effects. Theory connecting observed marks to sea lamprey feeding activity and host mortality is reviewed. Uncertainties regarding healing and attachment times, the probability of hosts surviving attacks, and problems in consistent classification of marks have led to widely divergent estimates of damages caused by sea lamprey. Laboratory and field studies are recommended to provide a firmer linkage between host blood loss, host mortality, and observed marks on surviving hosts, so as to improve estimates of damage.

Bence, James R.; Bergstedt, Roger A.; Christie, Gavin C.; Cochran, Phillip A.; Ebener, Mark P.; Koonce, Joseph F.; Rutter, Michael A.; Swink, William D.

2003-01-01

93

Frost flower formation on sea ice and lake ice Robert W. Style1  

E-print Network

Frost flower formation on sea ice and lake ice Robert W. Style1 and M. Grae Worster1 Received 22 January 2009; revised 20 April 2009; accepted 6 May 2009; published 10 June 2009. [1] Frost flowers to a class of vapour-related phenomena that includes freezing fog, hoar frost and dew. It has hitherto been

Worster, M. Grae

94

Levels of heavy metals in seals of Lake Ladoga and the White Sea  

Microsoft Academic Search

Between 1990 and 1993 samples of hair, liver, kidney and muscle were collected from 28 ringed seals from Lake Ladoga, Phoca hispida ladogensis, 20 ringed seals, Phoca hispida hispida, and three bearded seals, Erignathus barbatus, from the White Sea for heavy-metal residue analyses in tissues. The concentration of Hg, Cd, Pb, Cu, Ni and Zn were determined by atomic absorption

N. Medvedev; N. Panichev; H. Hyvrinen

1997-01-01

95

Assessment of sea lamprey (Petromyzon marinus) predation by recovery of dead lake trout (Salvelinus namaycush) from Lake Ontario, 1982-85  

USGS Publications Warehouse

During 1982-85, 89 dead lake trout (Salvelinus namaycush) were recovered with bottom trawls in U.S. waters of Lake Ontario: 28 incidentally during four annual fish-stock assessment surveys and 61 during fall surveys for dead fish. During the assessment surveys, no dead lake trout were recovered in April-June, one was recovered in August, and 27 were recovered in October or November, implying that most mortality from causes other than fishing occurred in the fall. The estimated numbers of dead lake trout between the 30- and 100-m depth contours in U.S. waters ranged from 16 000 (0.08 carcass/ha) in 1983 to 94 000 (0.46 carcass/ha) in 1982. Of 76 carcasses fresh enough to enable recognition of sea lamprey (Petromyzon marinus) wounds, 75 bore fresh wounds. Assuming that sea lamprey wounding rates on dead fish were the same as on live ones of the same length range (430-740 mm), the probability of 75 of the 76 dead lake trout bearing sea lamprey wounds was 3.5 x 10-63 if death was independent of sea lamprey attack, thus strongly implicating sea lampreys as the primary cause of death of fish in the sample. The recovery of only one unwounded dead lake trout also suggested that natural mortality from causes other than sea lamprey attactks is negligible.

Bergstedt, Roger A.; Schneider, Clifford P.

1988-01-01

96

Production of sea lamprey larvae from nests in two Lake Superior streams  

USGS Publications Warehouse

The life history of the landlocked sea lamprey, Petromyzon marinus, has been described by several authors, the two most recent of which are Applegate and Wigley. The only information on the production of larvae from nests of the sea lamprey was reported by Applegate, who counted the larvae from three nests in the Ocqueoc River, a tributary of Lake Huron. The present report presents data on the hatching success of sea lamprey larvae from 19 nests in two small tributaries of southern Lake Superior and indicates greater production per nest than that recorded by Applegate. Studies were conducted by personnel of the U.S. Bureau of Commercial Fisheries on the Little Garlic River, Marquette County, Michigan, and on the Traverse River, Keweenaw County, Michigan.

Manion, Patrick J.

1968-01-01

97

Estimating lake-wide abundance of spawning-phase sea lampreys (Petromyzon marinus) in the Great Lakes: extrapolating from sampled streams using regression models  

USGS Publications Warehouse

Lake-wide abundance of spawning-phase sea lampreys (Petromyzon marinus) can be used as one means to evaluate sea lamprey control efforts in the Great Lakes. Lake-wide abundance in each Great Lake was the sum of estimates for all streams thought to contribute substantial numbers of sea lampreys. A subset of these streams was sampled with traps and mark-recapture studies were conducted. When sea lampreys were captured in traps, but no mark-recapture study was conducted, abundance was estimated from a relation between trap catch and mark-recapture estimates observed in other years. In non-sampled streams, a regression model that used stream drainage area, geographic region, larval sea lamprey, production potential, the number of years since the last lampricide treatment, and spawning year was used to predict abundance of spawning-phase sea lampreys. The combination of estimates from sampled and non-sampled streams provided a 20-year time series of spawning-phase sea lamprey abundance estimates in the Great Lakes.

Mullett, Katherine M.; Heinrich, John W.; Adams, Jean V.; Young, Robert J.; Henson, Mary P.; McDonald, Rodney B.; Fodale, Michael F.

2003-01-01

98

Estimating lake-wide abundance of spawning-phase sea lampreys (Petromyzon marinus) in the great lakes: Extrapolating from sampled streams using regression models  

USGS Publications Warehouse

Lake-wide abundance of spawning-phase sea lampreys (Petromyzon marinus) can be used as one means to evaluate sea lamprey control efforts in the Great Lakes. Lake-wide abundance in each Great Lake was the sum of estimates for all streams thought to contribute substantial numbers of sea lampreys. A subset of these streams was sampled with traps and mark-recapture studies were conducted. When sea lampreys were captured in traps, but no mark-recapture study was conducted, abundance was estimated from a relation between trap catch and mark-recapture estimates observed in other years. In non-sampled streams, a regression model that used stream drainage area, geographic region, larval sea lamprey, production potential, the number of years since the last lampricide treatment, and spawning year was used to predict abundance of spawning-phase sea lampreys. The combination of estimates from sampled and non-sampled streams provided a 20-year time series of spawning-phase sea lamprey abundance estimates in the Great Lakes.

Mullett, K. M.; Heinrich, J. W.; Adams, J. V.; Young, R. J.; Henson, M. P.; McDonald, R. B.; Fodale, M. F.

2003-01-01

99

Growth of Lake Trout in Lake Superior before the Maximum Abundance of Sea Lampreys  

Microsoft Academic Search

The growth in length of lake trout (Salvelinus namaycush) from the inshore water of Lake Superior in 1953 increased with age from the 3rd to 9th year, and was nearly constant from the 9th to the 12th year. Growth was greatest in the 1st year (4.0 inches) and least in the 2nd and 3rd years (2.3 inches). Between the 4th

Jerold F. Rahrer

1967-01-01

100

Mark-recapture population estimates of parasitic sea lampreys (Petromyzon marinus) in Lake Huron  

USGS Publications Warehouse

Metamorphosed sea lampreys (Petromyzon marinus) were collected and marked at two points in their life cycle. Recently metamorphosed juveniles were collected from streams, marked with coded wire tags, and returned to migrate to the Great Lakes. Juveniles already in the lakes and feeding on teleost hosts were obtained from incidental catches by sport or commercial fisheries. Sea lampreys in the Great Lakes spend only 1 feeding year as parasites, and marked animals were recaptured during the spawning runs. For one marked group in each of four parasitic cohorts (feeding years 1991 to 1994) and two marked groups in each of three cohorts (feeding years 1998 to 2000) we recovered from 1.1 to 10.2 percent of marked animals. The number of metamorphosed animals present in autumn before migration to Lake Huron was estimated for five cohorts, with estimates ranging from 639 to 803 thousand. The number of feeding, parasitic animals present in Lake Huron in mid summer was estimated for five cohorts, with estimates ranging from 515,000 to 2,342,000. The larger estimates later in the parasitic year suggested that animals collected and marked from sport or commercial fisheries did not survive at the same rate as unmarked animals. It is recommended that only estimates from recaptures of animals marked in the streams before migration be used until it can be established why survival of juveniles obtained from sport or commercial fisheries might be affected.

Bergstedt, Roger A.; McDonald, Rodney B.; Mullett, Katherine M.; Wright, Gregory M.; Swink, William D.; Burnham, Kenneth P.

2003-01-01

101

Late-Quaternary morphostratigraphy of Lake St-Joseph (southeastern Canadian Shield): Evolution from a semi-enclosed glacimarine basin to a postglacial lake  

NASA Astrophysics Data System (ADS)

This paper reports and describes multibeam echosounder, subbottom profiler and sediment sampling data collected in Lake St-Joseph (southern Qubec), a formerly glacimarine sedimentary basin that has been glacio-isostatically uplifted to form a small lake. Its study provides a unique opportunity for investigating changes in sedimentary environments from a glacial sea to a postglacial lake. Multibeam bathymetry allows the observation of two basins separated by a bathymetric ridge and of mass movement deposits in both basins. High resolution seismic stratigraphy reveals the presence of seven seismic units. These seven units relate to the advance and retreat of the Laurentide ice-sheet over the region. Following ice-retreat, transparent (U3) and high amplitude reflection (U4) units were deposited during the Champlain Sea invasion. The transparent unit likely represents a rapidly retreating glacier, which allowed the deposition of massive silt and clay, whereas the high amplitude reflectors, which are internally composed of transparent to chaotic lenses, are interpreted as the result of a deceleration of ice-retreat or a stabilization of the glacier and of glacio-isostatic rebound. Overlying the Champlain Sea sediments, a unit composed of smaller laminations (U5) suggests that it was deposited during the marine to lacustrine transition, in a paraglacial environment. This is supported by its presence in the northern basin, where the Rivire-aux-Pins mouth is located and its absence in the southern basin, where no river is observed. The bathymetric ridge between the two basins thus limited sediment transport. Following the complete retreat of the Champlain Sea, organic-rich sediments (U7) were deposited in the lake. In the northern basin, the presence of the Rivire-aux-Pins allowed their deposition in the form of rhythmites whereas the absence of rivers in the southern basin resulted in the deposition of an acoustically transparent unit. A mass movement (U6) identified during the deposition of Unit 7 occurred around 1250 AD and is interpreted as earthquake-triggered.

Normandeau, Alexandre; Lajeunesse, Patrick; Philibert, Genevive

2013-09-01

102

SEA LAMPREY SPAWNING RUNS IN THE GREAT LAKES 1951  

E-print Network

,Iichigar> basin) ........ 7 3. Experimental sea laaiprsy bai'/rier dam in -the Black Ri.ver, Mackina-ar Co'onty, Miciiigan 32 U. Black River bai-rier dam. '.:iose--'ap of bai'rier dam shomng overhanging, o-uc-ved lip

103

78 FR 14444 - Drawbridge Operation Regulation; Lake Champlain, Swanton, VT  

Federal Register 2010, 2011, 2012, 2013

...of a train and then crank the draw back into the open position...opening motors to swing the draw open and closed, a standby...used to locally operate the draw, LED navigation lights, and...December through April each winter when the recreational...

2013-03-06

104

77 FR 67319 - Drawbridge Operation Regulation; Lake Champlain, Swanton, VT  

Federal Register 2010, 2011, 2012, 2013

...to locally operate the draw, LED navigation lights...owner proposes to open the draw upon receipt of a twenty-four...December through April each winter when the recreational...transit this bridge are in winter storage. As a result...to manually crank the draw closed to facilitate...

2012-11-09

105

Spatial and Seasonal Patterns of Natural Organic Matter Spectral Fluorescent Signatures in Lake Kinneret (Sea of Galilee) and its Catchment Basin  

Microsoft Academic Search

This paper presents a characterization of fluorescent natural organic matter (NOM) in Lake Kinneret (Sea of Galilee) and its catchment basin. Lake Kinneret, the large high-productive subtropical lake, is the only freshwater lake and one of the major water resources in Israel. The work is based on the analysis of the spectral fluorescent signatures (excitation emission matrices; EEM) of 167

M. Borisover; Y. Laor; A. Parparov; N. Bukhanovsky; M. Lado

2009-01-01

106

Diseases and parasites of the sea lamprey, Petromyzon marinus, in the Lake Huron basin  

USGS Publications Warehouse

Sea lampreys from the Lake Huron basin carried no external parasites and showed a fairly low degree of infection by internal parasites. The material examined represented three life-history stages of the sea lamprey. Recently transformed downstream migrants (215 specimens) harbored only nematodes belonging to the genus Camallanus. The percentage of infection was 2.3. Active feeders from the lake (29 lampreys) revealed the highest degree of parasitism (31.0 percent) with the following parasites present: Echinorhynchus coregoni Linkins; Triaenophorus crasses Forel; and Camallanus sp. Among the 257 sexually mature upstream migrants (14.8 percent infected) Echinorhynchus coregoni and E. leidyi Van Cleave were the most common. Only occasional nematodes and cestodes were found, which fact indicates a failure of the lamprey to carry these parasites to the end of its natural life. Of the parasites observed, only the nematodes gave evidence of serious damage to the host. The study suggests that the role played by parasites in the natural control of the sea lamprey in its new habitat in the upper Great Lakes is of minor importance.

McLain, Alberton L.

1952-01-01

107

J. ELLEN MARSDEN Rubenstein School of Environment and Natural Resources, University of Vermont  

E-print Network

vector. Lake Champlain Sea Grant , $101,00 2009-2010 Janice Adams, J. Ellen Marsden, James Johnson Fishery Commission, $175,623 2009-2010. Emerging threats on Lake Champlain. Levine, S., J. E. Marsden, and M. Watzin. Lake Champlain Sea Grant, $371,000. 2007 The effects of zebra mussel growth in different

Marsden, Ellen

108

Evolution of glacial lakes from the Northern Patagonia Icefield and terrestrial water storage in a sea-level rise context  

NASA Astrophysics Data System (ADS)

An increase of glacial lake area of 66.0 km2 has been measured at the periphery of the Northern Patagonia Icefield (NPI) between 1945 and 2011. Results have been obtained by digitizing the glacial lakes from Lliboutry's topographic map and from various multitemporal Landsat satellite scenes (1976, 1987, 2001 and 2011). This first complete glacial lake inventory of the NPI indicates a total lake area of 167.5 8.4 km2 for 2011, which represents an increase of 64.9% with respect to the total glacial lake area of the NPI in 1945 (101.6 19.1 km2). The highest area increase was experienced by the San Quintn Lake with an expansion of 18.0 km2 in the 1945-2011 period. Using a volume-area scaling model, a total volume increase of 4.8 km3 is estimated for the entire glacial lake population in the 66-year period. Based on the volumetric increase of the glacial lakes we compute a terrestrial water storage factor of 10% of the contribution of NPI to sea-level rise for the last decade (2001-2011), which is considered as a lower bound since lakes that have lost contact with the ice are not considered in the inventory. The increasing risk of Glacial Lake Outburst Floods (GLOF's) due to the glacial lake enlargement is also discussed.

Loriaux, Thomas; Casassa, Gino

2013-03-01

109

Deep sea and lake records of the Southeast Asian paleomonsoons for the last 25 thousand years  

NASA Astrophysics Data System (ADS)

High resolution paleoceanographic proxy records from a deep-sea core in the northern South China Sea (SCS) and palynological records from a lake core in central Taiwan have been measured for the last 25 kyr. The variations in these proxy records are interpreted in terms of the past variation in the Asian monsoons. The two consistent and complementary records suggest that the East Asian monsoon system has fluctuated significantly from a strengthened winter monsoon during the last glaciation (25,000-12,000 yr BP) through a moderate to weak winter and summer monsoons during the deglaciation (12,000-10,000 yr BP) to an enhanced summer monsoon in the Holocene. Strengthening of the winter monsoon during the glacial is deduced from decreases in winter SST and increases in productivity indicators, such the abundances of alkenones and total organic carbon in the SCS. A stronger summer monsoon during the Holocene is inferred from the increases in floral productivity, the sedimentation rate of peat, the deposition of storm-related clay layers in the lake sediment, and the higher abundance of thermophyte Castanopsis. The 25 kyr paleomonsoon history registered in the SCS core and the Taiwan lake sediments is in agreement with the climatic records of the Chinese Loess plateau.

Huang, Chi-Yue; Liew, Ping-Mei; Zhao, Meixun; Chang, Tzu-Chun; Kuo, Chao-Ming; Chen, Min-Te; Wang, Chung-Ho; Zheng, Lian-Fu

1997-01-01

110

Microbiology of the Red Sea (and other) deep-sea anoxic brine lakes.  

PubMed

The Red Sea harbours approximately 25 deep-sea anoxic brine pools. They constitute extremely unique and complex habitats with the conjugation of several extreme physicochemical parameters rendering them some of the most inhospitable environments on Earth. After 50 years of research mostly driven by chemists, geophysicists and geologists, the microbiology of the brines has been receiving increased interest in the last decade. Recent molecular and cultivation-based studies have provided us with a first glimpse on the enormous biodiversity of the local microbial communities, the identification of several new taxonomic groups, and the isolation of novel extremophiles that thrive in these environments. This review presents a general overview of these unusual biotopes and compares them with other similar environments in the Mediterranean Sea and the Gulf of Mexico, with a focus on their microbial ecology. PMID:23761304

Antunes, Andr; Ngugi, David Kamanda; Stingl, Ulrich

2011-08-01

111

Selecting Great Lakes streams for lampricide treatment based on larval sea lamprey surveys  

USGS Publications Warehouse

The Empiric Stream Treatment Ranking (ESTR) system is a data-driven, model-based, decision tool for selecting Great Lakes streams for treatment with lampricide, based on estimates from larval sea lamprey (Petromyzon marinus) surveys conducted throughout the basin. The 2000 ESTR system was described and applied to larval assessment surveys conducted from 1996 to 1999. A comparative analysis of stream survey and selection data was conducted and improvements to the stream selection process were recommended. Streams were selected for treatment based on treatment cost, predicted treatment effectiveness, and the projected number of juvenile sea lampreys produced. On average, lampricide treatments were applied annually to 49 streams with 1,075 ha of larval habitat, killing 15 million larval and 514,000 juvenile sea lampreys at a total cost of $5.3 million, and marginal and mean costs of $85 and $10 per juvenile killed. The numbers of juvenile sea lampreys killed for given treatment costs showed a pattern of diminishing returns with increasing investment. Of the streams selected for treatment, those with > 14 ha of larval habitat targeted 73% of the juvenile sea lampreys for 60% of the treatment cost. Suggested improvements to the ESTR system were to improve accuracy and precision of model estimates, account for uncertainty in estimates, include all potentially productive streams in the process (not just those surveyed in the current year), consider the value of all larvae killed during treatment (not just those predicted to metamorphose the following year), use lake-specific estimates of damage, and establish formal suppression targets.

Christie, Gavin C.; Adams, Jean V.; Steeves, Todd B.; Slade, Jeffrey W.; Cuddy, Douglas W.; Fodale, Michael F.; Young, Robert J.; Kuc, Miroslaw; Jones, Michael L.

2003-01-01

112

Microbial life in the Lake Medee, the largest deep-sea salt-saturated formation  

NASA Astrophysics Data System (ADS)

Deep-sea hypersaline anoxic lakes (DHALs) of the Eastern Mediterranean represent some of the most hostile environments on our planet. We investigated microbial life in the recently discovered Lake Medee, the largest DHAL found to-date. Medee has two unique features: a complex geobiochemical stratification and an absence of chemolithoautotrophic Epsilonproteobacteria, which usually play the primary role in dark bicarbonate assimilation in DHALs interfaces. Presumably because of these features, Medee is less productive and exhibits reduced diversity of autochthonous prokaryotes in its interior. Indeed, the brine community almost exclusively consists of the members of euryarchaeal MSBL1 and bacterial KB1 candidate divisions. Our experiments utilizing cultivation and [14C]-assimilation, showed that these organisms at least partially rely on reductive cleavage of osmoprotectant glycine betaine and are engaged in trophic cooperation. These findings provide novel insights into how prokaryotic communities can adapt to salt-saturated conditions and sustain active metabolism at the thermodynamic edge of life.

Yakimov, Michail M.; La Cono, Violetta; Slepak, Vladlen Z.; La Spada, Gina; Arcadi, Erika; Messina, Enzo; Borghini, Mireno; Monticelli, Luis S.; Rojo, David; Barbas, Coral; Golyshina, Olga V.; Ferrer, Manuel; Golyshin, Peter N.; Giuliano, Laura

2013-12-01

113

Microbial life in the Lake Medee, the largest deep-sea salt-saturated formation.  

PubMed

Deep-sea hypersaline anoxic lakes (DHALs) of the Eastern Mediterranean represent some of the most hostile environments on our planet. We investigated microbial life in the recently discovered Lake Medee, the largest DHAL found to-date. Medee has two unique features: a complex geobiochemical stratification and an absence of chemolithoautotrophic Epsilonproteobacteria, which usually play the primary role in dark bicarbonate assimilation in DHALs interfaces. Presumably because of these features, Medee is less productive and exhibits reduced diversity of autochthonous prokaryotes in its interior. Indeed, the brine community almost exclusively consists of the members of euryarchaeal MSBL1 and bacterial KB1 candidate divisions. Our experiments utilizing cultivation and [(14)C]-assimilation, showed that these organisms at least partially rely on reductive cleavage of osmoprotectant glycine betaine and are engaged in trophic cooperation. These findings provide novel insights into how prokaryotic communities can adapt to salt-saturated conditions and sustain active metabolism at the thermodynamic edge of life. PMID:24352146

Yakimov, Michail M; La Cono, Violetta; Slepak, Vladlen Z; La Spada, Gina; Arcadi, Erika; Messina, Enzo; Borghini, Mireno; Monticelli, Luis S; Rojo, David; Barbas, Coral; Golyshina, Olga V; Ferrer, Manuel; Golyshin, Peter N; Giuliano, Laura

2013-01-01

114

Microbial life in the Lake Medee, the largest deep-sea salt-saturated formation  

PubMed Central

Deep-sea hypersaline anoxic lakes (DHALs) of the Eastern Mediterranean represent some of the most hostile environments on our planet. We investigated microbial life in the recently discovered Lake Medee, the largest DHAL found to-date. Medee has two unique features: a complex geobiochemical stratification and an absence of chemolithoautotrophic Epsilonproteobacteria, which usually play the primary role in dark bicarbonate assimilation in DHALs interfaces. Presumably because of these features, Medee is less productive and exhibits reduced diversity of autochthonous prokaryotes in its interior. Indeed, the brine community almost exclusively consists of the members of euryarchaeal MSBL1 and bacterial KB1 candidate divisions. Our experiments utilizing cultivation and [14C]-assimilation, showed that these organisms at least partially rely on reductive cleavage of osmoprotectant glycine betaine and are engaged in trophic cooperation. These findings provide novel insights into how prokaryotic communities can adapt to salt-saturated conditions and sustain active metabolism at the thermodynamic edge of life. PMID:24352146

Yakimov, Michail M.; La Cono, Violetta; Slepak, Vladlen Z.; La Spada, Gina; Arcadi, Erika; Messina, Enzo; Borghini, Mireno; Monticelli, Luis S.; Rojo, David; Barbas, Coral; Golyshina, Olga V.; Ferrer, Manuel; Golyshin, Peter N.; Giuliano, Laura

2013-01-01

115

The sterile-male-release technique in Great Lakes sea lamprey management  

USGS Publications Warehouse

The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N- methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduction in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

Twohey, M. B.; Heinrich, J. W.; Seelye, J. G.; Fredricks, K. T.; Bergstedt, R. A.; Kaye, C. A.; Scholefield, R. J.; McDonald, R. B.; Christie, G. C.

2003-01-01

116

The sterile-male-release technique in Great Lakes sea lamprey management  

USGS Publications Warehouse

The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduction in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

Twohey, Michael B.; Heinrich, John W.; Seelye, James G.; Fredricks, Kim T.; Bergstedt, Roger A.; Kaye, Cheryl A.; Scholefield, Ron J.; McDonald, Rodney B.; Christie, Gavin C.

2003-01-01

117

Frozen Hydrocarbon Ponds on Titan: Implications for Titans Lakes and Seas  

NASA Astrophysics Data System (ADS)

Cassini Imaging Science Subsystem (ISS) observations have detected widespread darkening of Titans surface believed to be the result of rainfall: in 2005 at Arrakis Planitia, near Titans south pole (Turtle et al., 2009, GRL 36, L02204), and in 2009 in Titans tropics (Turtle et al., 2011, Science 331, 14141417). Cassini Visual and Infrared Mapping Spectrometer (VIMS) and ISS observations revealed that, following the tropics storm, the albedo of the wetted surfaces increased, beyond even their original albedo, then slowly faded back to a pre-rain brightness over ~10 months (Barnes et al., 2013, Planet. Sci. 2, 1). Herein we report on combined analysis of Cassini VIMS, Synthetic Aperture Radar (SAR), and ISS observations of Arrakis Planitia acquired in the years following the 2005 precipitation event. The low-albedo surface (observed in 2005 ISS images) correlates with local topography (inferred from 2008 SAR data), consistent with a liquid that has pooled on the surface. Like the equatorial event, the low-albedo surface at Arrakis Planitia is observed in VIMS data acquired from 2007 to 2009 to increase in albedo. Unlike the tropics event, however, four years after the initial precipitation event (more than 2 years after the increased albedo was first observed), these south-polar regions were still bright compared to their pre-precipitation albedo. The combined results support the hypothesis that hydrocarbons rained onto Titans surface and subsequently froze. Furthermore, because Titan's lakes and seas are almost certainly liquid, our results imply that some mechanism is preventing Titan's lakes and seas from freezing one obvious hypothesis is that Titans lakes and seas differ in composition from Titans presumed methane-rich rain (likely the result of the concentration of minor constituents).

Soderblom, Jason M.; Barnes, Jason W.; Brown, Robert H.; Hayes, Alexander G.; Perry, Jason E.; Soderblom, Laurence A.; Turtle, Elizabeth P.

2014-11-01

118

Classification of sea lamprey (Petromyzon marinus) attack marks on Great Lakes lake trout (Salvelinus namaycush)  

USGS Publications Warehouse

Criteria for the classification of marks inflicted by sea lamprey (Petromyzon marinus) into nine categories were developed from laboratory studies in an attempt to refine the classification system used in field assessment work. These criteria were based on characteristics of the attachment site that could be identified under field conditions by unaided visual means and by touching the attachment site. Healing of these marks was somewhat variable and was influenced by the size of lamprey, duration of attachment, severity of the wound at lamprey detachment, season and water temperature, and by other less obvious factors. Even under laboratory conditions staging of some wounds was difficult, especially at low water temperatures. If these criteria are to be used effectively and with precision in the field, close examination of individual fish may be required. If the feeding and density of specific year-classes of sea lampreys are to be accurately assessed on an annual basis, close attention to the wound size (as it reflects the size of the lamprey's oral disc) and character of wounds on fish will be required as well as consideration of the season of the year in which they are observed.

King, Everett Louis, Jr.

1980-01-01

119

Sea-rain-lake relation in the Last Glacial East Mediterranean revealed by ? 18O-? 13C in Lake Lisan aragonites  

NASA Astrophysics Data System (ADS)

We investigated the Sea-Rain-Lake relation during the Last Glacial-Holocene in the East Mediterranean region by comparing the ? 18O and ? 13C records of authigenic aragonite deposited in Lake Lisan, the Dead Sea, Mediterranean foraminifera, and speleothems. The Lisan Formation data display long- and short-term variations of ? 18O, representing steady-state conditions of the lake (e.g., 5.6 0.5 and 4.5 1 in the Upper and Lower Members of the Lisan Formation, respectively), and short-term excursions reflecting large floods and droughts. The long-term (steady-state) ? 18O values of the Lisan aragonites show similarity to the corresponding time-equivalent records of the Eastern Mediterranean foraminifera and Judea Mountain speleothems: The Last Glacial deposits are in all of them 2-3 heavier than the Holocene ones. We interpret this similarity as reflecting the significance of the source effect on the long-term behavior of isotopic reservoirs: Speleothem ? 18O is strongly influenced by the marine reservoir that contributes its vapor to rain formation; the lake ? 18O is dominated by the composition of the inflowing water. Short-term variations in the isotopic composition of rainfall are dominated by the amount effect and the temperature and those of the Lake's upper water mass by the lake's water balance. ? 13C values are more variable than ? 18O in the same Lisan sequences (e.g., ? 13C in the Lower Member is 1.0 1.7, whereas ? 18O is 4.6 0.7) and are 1 to 1.5 higher in the Upper Member than in the Lower and Middle Members of the Lisan Formation. These variations reflect significant increase in primary productivity of the lake and algal bloom activity. It appears that the hypersaline-saline lakes were not as "dead" as the Dead Sea is and that algal activity had an important impact upon the geochemistry of Lake Lisan. The ? 18O data combined with independent geochemical and limnologic information (e.g., level fluctuations) indicate that Lisan time was characterized by high precipitation-high lake stands-high atmospheric humidity, whereas the Holocene Dead Sea shows the opposite behavior. This paleoclimatic reconstruction is consistent with independent evidence for significantly wetter conditions in the East Mediterranean region during the Last Glacial period.

Kolodny, Yehoshua; Stein, Mordechai; Machlus, Malka

2005-08-01

120

Evolution of Titan's Lakes and Seas: Insights from Recent Infrared Observations  

NASA Astrophysics Data System (ADS)

Titan's North Pole has been illuminated since the spring equinox in August 2009, allowing optical remote sensing instruments to acquire images of the lakes and seas that were discovered by the radar instrument earlier in the Cassini mission [1]. The illumination geometry continually improves with the incidence angle decreasing to its minimum at the summer solstice in 2017. Combined with highly inclined flybys that allow for small values of the emission angle, the 2013 observations are much less affected by the haze scattering because the optical path through the atmosphere is much shorter. The Visual and Infrared Mapping Spectrometer (VIMS) can observe Titan's surface in seven infrared atmospheric windows between 0.96- and 5-?m. This study describes observations acquired during the recent T93 flyby on July 26, 2013. The footprint ranges from 10 km/pixel to 3 km/pixel. Maps of the three large seas (Ligeia Mare, Punga Mare, and Kraken Mare) at seven different wavelengths are being constructed and a mosaic of the lake area is being assembled. Ligeia Mare was previously imaged by the VIMS in June 2010 [2]. A preliminary analysis of the 2-?m map suggests that the shoreline has not evolved since 2010. The shape of the 2- ?m atmospheric window will be compared between the two images and between the mare and the shore to investigate whether liquid ethane is present as is the case on Ontario lacus [3]. The lake area located between 0 and 90W was imaged with a resolution that allows comparison with the radar images. A preliminary comparison between the two data sets shows a very strong correlation. One part of Punga mare and a lake known as Kivu lacus were acquired on the same image. The northeastern part of Punga Mare seems entailed by a river network. No connections between Punga mare and Kivu lacus are observed on the VIMS image. Kivu lacus seems to lie in the center of a circular depression whose limit is bright at 2-?m. Equipotential maps are built from the topographic information obtained by the radar team [4] and the gravity potential determined by the Radio Science team [5]. As already determined [6], the topographic polar radius is smaller than the equipotential polar radius of an ellipsoid having the same volume. The three seas are indeed located in the depressions where the value of the gravitational potential is largest. On the other hand, the correlation is less clear with the lakes that seem to sit at higher elevation. If confirmed, this observation suggests that a putative subsurface connection between the lakes and the seas would drain out the lakes. This work has been performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. [1] Stofan, E.R. et al. (2007) Nature 445, 61-64 [2] Sotin C. et al. (2012) Icarus 221, 768-786 [3]Brown R.H. et al. (2008) Nature 454, 607-609 [4] Lorenz R.D. (2013) Icarus 225, 367-377 [5] Iess L. et al. (2012) Science 337, 457-459 [6] Zebker H.A. (2009) Science 324, 921-923.

Sotin, C.; Seignovert, B.; Lawrence, K.; Barnes, J. W.; Brown, R. H.; Hayes, A.; Le Mouelic, S.; Baines, K. H.; Buratti, B. J.; Clark, R. N.; Nicholson, P. D.

2013-12-01

121

Compensatory mechanisms in Great Lakes sea lamprey populations: Implications for alternative control strategies  

USGS Publications Warehouse

Compensatory mechanisms are demographic processes that tend to increase population growth rates at lower population density. These processes will tend to reduce the effectiveness of actions that use controls on reproductive success to suppress sea lamprey (Petromyzon marinus), an economically important pest in the Great Lakes. Historical evidence for compensatory mechanisms in sea lamprey populations was reviewed, and revealed: (1) strong evidence for shifts in sex ratios as sea lamprey abundance was reduced in the early years of the control program; (2) weak and equivocal evidence for increased growth rates of sea lamprey cohorts re-colonizing streams following a lampricide treatment; and (3) suggestions of other compensatory processes, such as earlier ages at metamorphosis, but with little empirical evidence. Larval size distribution data for cohorts in the first and second years following a lampricide treatment (26 pairs of cohorts in 20 streams) was analyzed and did not indicate a consistent pattern of more rapid growth of the first colonizing cohort (only 11 of 33 cases). To test for compensation between spawning and age-1 in sea lamprey populations, data were analyzed for 49 stream-years for which spawning female abundance was known and age-1 abundance was estimated in the following year. A fit of these data to a Ricker stock-recruitment function showed evidence for compensation, measured as reduced survival to age 1 at higher abundance of spawning females. More obvious, however, was a large amount of density-independent variation in survival, which tends to mask evidence for compensatory survival. The results were applied to a simple model that simulates sea lamprey populations and their control in a hypothetical lake. Control strategies that targeted reproductive success performed far less well than comparable strategies that targeted larval populations, because density-independent recruitment variation leads to occasional strong year classes even when spawner abundance is reduced to low levels through alternative control. It is concluded that further study of recruitment variation in lamprey populations is critical to rationalizing alternative controls that target reproductive success, and that recruitment variation needs to be incorporated into models used to evaluate sea lamprey control options.

Jones, M.L.; Bergstedt, R.A.; Twohey, M.B.; Fodale, M.F.; Cuddy, D.W.; Slade, J.W.

2003-01-01

122

Compensatory mechanisms in Great Lakes sea lamprey populations: implications for alternative control strategies  

USGS Publications Warehouse

Compensatory mechanisms are demographic processes that tend to increase population growth rates at lower population density. These processes will tend to reduce the effectiveness of actions that use controls on reproductive success to suppress sea lamprey (Petromyzon marinus), an economically important pest in the Great Lakes. Historical evidence for compensatory mechanisms in sea lamprey populations was reviewed, and revealed: (1) strong evidence for shifts in sex ratios as sea lamprey abundance was reduced in the early years of the control program; (2) weak and equivocal evidence for increased growth rates of sea lamprey cohorts re-colonizing streams following a lampricide treatment; and (3) suggestions of other compensatory processes, such as earlier ages at metamorphosis, but with little empirical evidence. Larval size distribution data for cohorts in the first and second years following a lampricide treatment (26 pairs of cohorts in 20 streams) was analyzed and did not indicate a consistent pattern of more rapid growth of the first colonizing cohort (only 11 of 33 cases). To test for compensation between spawning and age-1 in sea lamprey populations, data were analyzed for 49 stream-years for which spawning female abundance was known and age-1 abundance was estimated in the following year. A fit of these data to a Ricker stock-recruitment function showed evidence for compensation, measured as reduced survival to age 1 at higher abundance of spawning females. More obvious, however, was a large amount of density-independent variation in survival, which tends to mask evidence for compensatory survival. The results were applied to a simple model that simulates sea lamprey populations and their control in a hypothetical lake. Control strategies that targeted reproductive success performed far less well than comparable strategies that targeted larval populations, because density-independent recruitment variation leads to occasional strong year classes even when spawner abundance is reduced to low levels through alternative control. It is concluded that further study of recruitment variation in lamprey populations is critical to rationalizing alternative controls that target reproductive success, and that recruitment variation needs to be incorporated into models used to evaluate sea lamprey control options.

Jones, Michael L.; Bergstedt, R.A.; Twohey, Michael B.; Fodale, Michael F.; Cuddy, Douglas W.; Slade, Jeffrey W.

2003-01-01

123

Changes in mortality of lake trout (Salvelinus namaycush) in Michigan waters of Lake Superior in relation to sea lamprey (Petromyzon marinus) predation, 1968-78  

USGS Publications Warehouse

Total mortality rates of lake trout (Salvelinus namaycush) of age VII and older from eastern Lake Superior were estimated from catch curves of age distributions each year in 1968-78. The instantaneous rate of total mortality Z varied from 0.62 to 2.31 in close synchrony with sea lamprey (Petromyzon marinus) wounding rates on lake trout. The regression of transformed Z on the index of lamprey wounding accounted for over 89% of the variation in lake trout mortality (rA? = 0.893). An iterative method of estimating rates of exploitation u, instantaneous rates of fishing mortality F, K (a constant relating sample catch per unit effort to population size), instantaneous normal natural mortality rate M, and instantaneous rate of mortality due to sea lamprey predation L from the sample catch per unit effort and total catch by the fishery is presented. A second method using the results of a 1970-71 tagging study to estimate the mean F in 1970-77 yielded closely similar results to the above and is presented as corroboration. The estimates of u, F, and M appear to be reasonable. F ranged from 0.17 in 1974 to 0.42 in 1969 and M was estimated at 0.26. L varied from 0.21 in 1974 to 1.70 in 1968. Management implications of various policies concerning sea lamprey control, exploitation, and stocking are discussed.

Pycha, Richard L.

1980-01-01

124

Techniques and methods for estimating abundance of larval and metamorphosed sea lampreys in Great Lakes tributaries, 1995 to 2001  

USGS Publications Warehouse

Before 1995, Great Lakes streams were selected for lampricide treatment based primarily on qualitative measures of the relative abundance of larval sea lampreys, Petromyzon marinus. New integrated pest management approaches required standardized quantitative measures of sea lamprey. This paper evaluates historical larval assessment techniques and data and describes how new standardized methods for estimating abundance of larval and metamorphosed sea lampreys were developed and implemented. These new methods have been used to estimate larval and metamorphosed sea lamprey abundance in about 100 Great Lakes streams annually and to rank them for lampricide treatment since 1995. Implementation of these methods has provided a quantitative means of selecting streams for treatment based on treatment cost and estimated production of metamorphosed sea lampreys, provided managers with a tool to estimate potential recruitment of sea lampreys to the Great Lakes and the ability to measure the potential consequences of not treating streams, resulting in a more justifiable allocation of resources. The empirical data produced can also be used to simulate the impacts of various control scenarios.

Slade, Jeffrey W.; Adams, Jean V.; Christie, Gavin C.; Cuddy, Douglas W.; Fodale, Michael F.; Heinrich, John W.; Quinlan, Henry R.; Weise, Jerry G.; Weisser, John W.; Young, Robert J.

2003-01-01

125

Changing climate and sea level alter Hg mobility at Lake Tulane, Florida, U.S.  

PubMed

Between 45,000 cal years BP and the beginning of the Holocene, the accumulation rate for Hg in sediments of Lake Tulane, Florida ranged from ?2 to 10 ?g m(-2) yr(-1), compared with 53 ?g Hg m(-2) yr(-1) in the 1985-1990 period of anthropogenic input. The locality experienced regional draw-down of the water table during the Wisconsinan glaciation, which lowered global sea level by nearly 130 m. Natural atmospheric deposition of Hg to the surrounding area resulted in long-term (ca. 100,000 years) sequestration of this atmospheric flux of Hg, primarily by adsorption in the oxic Al- and Fe-hydroxide-rich sandy subsoil. Global sea level rise during deglaciation led to a rising regional water table, flooding the oxidized soils surrounding Tulane. Iron and adsorbed Hg were mobilized by reductive dissolution and transported by groundwater flow to Lake Tulane and ultimately to the accumulating sediment. The accumulation rate of Hg (and Fe) increased rapidly about 16,000 cal years BP, peaked at nearly 60 ?g Hg m(-2) yr(-1) ca. 13,000-14,000 cal years BP, declined sharply during the Younger Dryas, and then increased sharply to a second 60 ?g Hg m(-2) yr(-1) peak about 5000 cal years BP. Thereafter, it declined nearly to background by 900 cal years BP. In similar geologic situations, rapid modern sea level rise will initiate this process globally, and may mobilize large accumulations of Hg and lesser amounts of As, and other redox sensitive metals to groundwater and surface water. PMID:23043314

Jacobson, G L; Norton, S A; Grimm, E C; Edgar, T

2012-11-01

126

Linear, one-dimensional models of the surface and internal standing waves for a long and narrow lake  

Microsoft Academic Search

Linear, one-dimensional, analytical, and numerical models for seiches (standing waves) existing at the surface and on the internal interface between the upper warm and bottom cold layers for a long, narrow lake are developed. Using the specific bathymetric and thermal structures of a lake, Lake Champlain, these models predict the periods, nodal locations, vertical displacements, and current velocities associated with

Robert B. Prigo; T. O. Manley; Benjamin S. H. Connell

1996-01-01

127

Emerging pollutants in the North Sea in comparison to Lake Ontario, Canada, data.  

PubMed

In the present study, the concentrations and fate of contaminants such as organophosphate flame retardants and plasticizers, musk compounds such as galaxolide (HHCB), tonalide (AHTN), musk ketone and musk xylene, the bactericide triclosan, as well as the metabolites HHCB-lactone and triclosan-methyl were compared in the aqueous phase of the German Bight (North Sea). The concentrations of these compounds were around 1 to 10 ng/L in nearshore areas, and the concentrations were lower in the more pristine areas. The highest concentrations were determined for tris-(2-chloro-isopropyl) phosphate in the North Sea with concentration exceeding 10 ng/L even for the offshore samples. The samples contained 1 to 20 ng/L chlorinated organophosphates, approximately 1 ng/L nonchlorinated organophosphates, and 0.3 to 3 ng/L fragrance compounds. Some samples from Lake Ontario (Canada) were analyzed in comparison. Per capita emissions were calculated for both regions. These emissions were compared and turned out to be very similar for the Canadian and German locations. For the North Sea, some observations concerning stability, dilution, and degradation, as well as sources of the respective substances, were performed. These data indicate that the chlorinated organophosphates and some musk fragrances exhibit half lives exceeding the residence times and thus can be considered to be persistent in this ecosystem. In the German Bight, the river Elbe is the dominating source for the more hydrophilic compounds, such as chlorinated organophosphate flame retardants, which are diluted only into the North Sea. However, for the more lipophilic compounds such as the musk fragrances, different input patterns as well as distribution patterns are relevant, though the river Elbe is still a major source of pollution to the German Bight of the North Sea. The data seem to indicate either relevant inputs further west of the sampling area or mobilization from the sediments. PMID:17571671

Andresen, Jens Arne; Muir, Derek; Ueno, Daisuke; Darling, Colin; Theobald, Norbert; Bester, Kai

2007-06-01

128

Oxygen isotope composition of water and snow-ice cover of isolated lakes at various stages of separation from the White Sea  

NASA Astrophysics Data System (ADS)

This study aimed to analyze the oxygen isotope composition of water, ice, and snow in water bodies isolated from the White Sea and to identify the structural peculiarities of these pools during the winter period. The studies were performed during early spring in Kandalaksha Bay of the White Sea, in Velikaya Salma Strait and in Rugoserskaya Inlet. The studied water bodies differ in their degree of isolation from the sea. In particular, Ermolinskaya Inlet has normal water exchange with the sea; the Lake on Zelenyi Cape represents the first stage of isolation; i. e., it has permanent water exchange with the sea by the tide. Kislo-Sladkoe Lake receives sea water from time to time. Trekhtsvetnoe Lake is totally isolated from the sea and is a typical meromictic lake. Finally, Nizhnee Ershovskoe Lake exhibits some features of a saline water body. The oxygen isotope profile of the water column in Trekhtsvetnoe Lake allows defining three layers; this lake may be called typically meromictic. The oxygen isotope profile of the water column in Kislo-Sladkoe Lake is even from the surface to the bottom. The variability of ?18O is minor in Lake on Zelenyi Cape. A surface layer (0-1 m) exists in Nizhnee Ershovskoe Lake, and the oxygen isotope variability is well pronounced. Deeper, where the freshwater dominates, the values of ?18vary insignificantly disregarding the water depth and temperature. This fresh water lake is not affected by the seawater and is not stratified according to the isotope profile. It is found that applying the values of ?18 and profiles of temperature and salinity may appear as an effective method in defining the water sources feeding the water bodies isolated from the sea environment.

Lisitzin, A. P.; Vasil'chuk, Yu. K.; Shevchenko, V. P.; Budantseva, N. A.; Krasnova, E. D.; Pantyulin, A. N.; Filippov, A. S.; Chizhova, Ju. N.

2013-04-01

129

Concentrations of organotin compounds in various fish species in the Finnish lake waters and Finnish coast of the Baltic Sea  

Microsoft Academic Search

Organotin compounds (OTCs) leaching from the antifouling paints used in boats and ships have contaminated many water areas worldwide. The purpose of this study was to obtain a general view of the organotin contamination in fish in Finnish lake areas and Finnish coast of the Baltic Sea using perch as the main indicator species. Perch sampling covered areas presumed as

Panu Rantakokko; Anja Hallikainen; Riikka Airaksinen; Pekka J. Vuorinen; Antti Lappalainen; Jaakko Mannio; Terttu Vartiainen

2010-01-01

130

[Book Review] The Dead Sea, the lake and its setting, edited by T. Niemi, Z. Ben-Avraham, J. Gat  

USGS Publications Warehouse

Review of The Dead Sea, the Lake and its Setting. Tina M. Niemi, Zvi Ben-Avraham, and Joel R. Gat (Editors). Oxford Monographs on Geology and Geophysics No. 36. Oxford University Press, N.Y. 286 pp. ISBN 0-19-508703-8, 1997. $75.

ten Brink, Uri

1998-01-01

131

A Microscopic Approach to Investigate Bacteria under In-Situ Conditions in Arctic Lake Ice: Initial Comparisons to Sea Ice  

NASA Astrophysics Data System (ADS)

To better understand constraints on bacteria at extremely low temperatures in ice, we describe here the adaptation of methods previously developed for sea ice to high magnification imaging of bacteria within fluid inclusions of Arctic lake ice under insitu conditions. Bacterial staining procedures, using the DNA-specific fluorescent stain DAPI, epifluorescence microscopy and image analysis were applied to lake-ice sections at in situ temperature (-5C). Abundances of total, attached, free-living and metabolically active lake-ice bacteria were also determined from samples melted at 0C using the fluorescent stains DAPI and CTC. Initial results indicate that, compared to sea ice at the same in situ temperature, lake ice contains fewer and more isolated liquid inclusions, limiting transport of fluids and motion of bacteria. Metabolically active cells were found in all ice samples (0.1 to 2.0{%} of the total counts), but on average less than in sea ice. Up to 50{%} of the total bacterial community were found to be associated with particles > 3 ? m in size; of the metabolically active cells, a smaller fraction may be attached than in sea ice. Our results expand the spectrum of information available on bacteria in ice on a scale relevant to the organism and provide insight into characteristics of frozen microbial habitats on Earth and perhaps elsewhere in the Universe.

Junge, Karen; Deming, Jody W.; Eicken, Hajo

2004-06-01

132

Passage of Four Teleost Species Prior to Sea Lamprey ( Petromyzon marinus) Migration in Eight Tributaries of Lake Superior, 1954 to 1979  

Microsoft Academic Search

Seasonally operated barriers in rivers are used by the Great Lakes Fishery Commission to block adult sea lamprey (Petromyzon marinus) migrations, yet pass other fish during some part of the year. Knowledge of the overlap of spawning migrations of sea lampreys and other fish species are vital for the efficient operation of the Commission's barrier program. The migration of sea

Gregory L. Klingler; Jean V. Adams; John W. Heinrich

2003-01-01

133

Classifying sea lamprey marks on Great Lakes lake trout: Observer agreement, evidence on healing times between classes, and recommendations for reporting of marking statistics  

USGS Publications Warehouse

In 1997 and 1998 two workshops were held to evaluate how consistent observers were at classifying sea lamprey (Petromyzon marinus) marks on Great Lakes lake trout (Salvelinus namaycush) as described in the King classification system. Two trials were held at each workshop, with group discussion between trials. Variation in counting and classifying marks was considerable, such that reporting rates for A1-A3 marks varied two to three-fold among observers of the same lake trout. Observer variation was greater for classification of healing or healed marks than for fresh marks. The workshops highlighted, as causes for inconsistent mark classification, both departures from the accepted protocol for classifying marks by some agencies, and differences in how sliding and multiple marks were interpreted. Group discussions led to greater agreement in classifying marks. We recommend ways to improve the reliability of marking statistics, including the use of a dichotomous key to classify marks. Laboratory data show that healing times of marks on lake trout were much longer at 4??C and 1??C than at 10??C and varied greatly among individuals. Reported A1-A3 and B1-B3 marks observed in late summer and fall collections likely result from a mixture of attacks by two year classes of sea lamprey. It is likely that a substantial but highly uncertain proportion of attacks that occur in late summer and fall lead to marks that are classified as A1-A3 the next spring. We recommend additional research on mark stage duration.

Ebener, M.P.; Bence, J.R.; Bergstedt, R.A.; Mullett, K.M.

2003-01-01

134

Hydrogen sulfide production and volatilization in a polymictic eutrophic saline lake, Salton Sea, California.  

PubMed

The Salton Sea is a large shallow saline lake located in southern California that is noted for high sulfate concentrations, substantial algal productivity, and very warm water column temperatures. These conditions are well-suited for sulfide production, and sulfide has been implicated in summer fish kills, although no studies have been conducted to specifically understand hydrogen sulfide production and volatilization there. Despite polymictic mixing patterns and relatively short accumulation periods, the amount of sulfide produced is comparable to meromictic lakes. Sulfide levels in the Salton Sea reached concentrations of 1.2 mmol L(-1) of total free sulfide in the hypolimnion and 5.6 mmol L(-1) in the sediment pore water. Strong winds in late July mixed H2S into the surface water, where it depleted the entire water column of dissolved oxygen and reached a concentration of 0.1 mmol L(-1). Sulfide concentrations exceeded the toxicity threshold of tilapia (Oreochromis mossambicus) and combined with strong anoxia throughout the water column, resulted in a massive fish kill. The mixing of sulfide into the surface waters also increased atmospheric H2S concentrations, reaching 1.0 micromol m(-3). The flux of sulfide from the sediment into the water column was estimated to range from 2-3 mmol m(-2) day(-1) during the winter and up to 8 mmol m(-2) day(-1) during the summer. Application of the two-layer model for volatilization indicates that up to 19 mmol m(-2) day(-1) volatilized from the surface during the mixing event. We estimate that as much as 3400 Mg year(-1) or approximately 26% of sulfide that diffused into the water column from the deepest sediments may have been volatilized to the atmosphere. PMID:18760446

Reese, Brandi Kiel; Anderson, Michael A; Amrhein, Christopher

2008-11-15

135

A new method of quantifying discharge of small rivers into lakes and inland seas  

NASA Astrophysics Data System (ADS)

Continental discharge is an important component of the global hydrological cycle, providing the majority of the input part of the ocean water balance. Buoyant inflow usually causes surface density stratification at the large shelf areas, and plays a significant role in physical, chemical, and biological processes there that is especially important for the lakes and inland seas. Although there is a lack of discharge data for most of rivers in a global scale. Regular direct measurements of discharge are performed only for a relatively small number of rivers, generally the biggest ones or ones that flow through densely populated areas. Within this problem an indirect method of assuming a volume of river discharge was developed. The general idea of the method is the following. Firstly, the spatial surface spread of the plume generated by the considered river discharge is identified using high resolution satellite imagery of the coastal zone adjacent to the river estuary. Secondly, a series of numerical simulations of the river runoff spread is performed under various prescribed external forcing conditions which include the discharge rate. Varying forcing conditions we iteratively improve the accordance between simulated and observed river plumes therefore consequentially specifying the value of river discharge. The developed method was applied and validated against in situ date for several rivers feeding the Black Sea. Practical importance of this work consists in the fact, that the suggested method is an alternative for the expensive and laborious direct measurements of the river discharge, which are used nowadays.

Osadchiev, Alexander; Zavialov, Peter

2014-05-01

136

Lithosphere-biosphere interaction at a shallow-sea hydrothermal vent site; Hot Lake, Panarea, Italy  

NASA Astrophysics Data System (ADS)

Deep-Sea hydrothermal systems are unique habitats for microbial life with primary production based on chemosynthesis and are considered to be windows to the subsurface biosphere. It is often overlooked, however, that their far more accessible shallow-sea counterparts are also valuable targets to study the effects of hydrothermal activity on geology, seawater chemistry and finally, on microbial life. Such an area of shallow marine hydrothermal venting is observed approximately 2.5 km east of Panarea Island (Sicily, Italy). This system is characterized by fluid temperatures of up to 135 C, gas emissions dominated by CO2 and precipitation of elemental sulfur on the seafloor. In an interdisciplinary project to investigate the influence of geofuels on marine microbiota, sediment cores and pore fluids were sampled for geological and geochemical analyses. An attempt was made to link these geochemical data with a characterization of the microbial community. One of the investigated sites (Lago Caldo, Hot Lake) is an oval-shaped (~10 by 6 meters) shallow (~2.5 m deep) depression covered by elemental sulfur. The sediments in this depression are strongly affected by hydrothermal activity: the pH of pore fluids is in a range between 5 and 6; the salinity is approximately two times higher than seawater. In situ temperatures of 36 C and 74 C (10 cm sediment depth) at two different locations within Hot Lake indicate variability in hydrothermal flux. The sediment surface layer is anoxic, and with increasing depth from the sediment-water interface, sulfate concentrations decrease from ~30 mM to less than 10 mM, whereas sulfide concentrations increase from less than 50 ?m to ~1000 ?m at 25 cm sediment depth, thus suggesting a higher potential for energy gain based on sulfur disequilibrium. As indicated by the variability in the sediment temperatures at 10 cm, fluid fluxes and mixing with seawater is not found to be uniform at Hot Lake. This is reflected in variability of the pore fluids geochemistry (anions, cations and stable isotope composition of water and sulfate) of depth profiles. DNA-fingerprinting techniques (DGGE, ARISA) revealed distinctly different bacterial 16S rRNA gene patterns for three separate sediment cores taken at Hot Lake. Intact polar lipid (IPL) biomarker analysis revealed a dominance of bacterial over archaeal biomass. The bacterial IPLs were mainly comprised of diether and diester phospholipids and ornithine lipids, indicative of viable thermophilic sulfate-reducing and acidophilic sulfide-oxidizing bacteria. Bacterial IPL abundance was highest in the sediment surface layer. Fluorescence in situ hybridization showed that with increasing depth and temperature, the abundance of archaea increased relative to that of bacteria. Comparative 16S rRNA gene analysis revealed a moderate diversity of bacteria, and a dominance of epsilonproteobacterial sequences. Cultured representatives of the detected epsilonproteobacterial classes are known to catalyze elemental sulfur reduction and oxidation reactions and to mediate the formation of iron-sulfides, including framboidal pyrite, which was found in sediment samples. We conclude that mixing between hydrothermal fluids and seawater leads to distinctly different temperature gradients and ecological niches in Hot Lake sediments. From the geochemical profiles and a preliminary characterization of the microbiological community, we found strong evidence of sulfur-related metabolism. Further investigation of certain clusters of bacteria and archaea as well as gene expression analysis will give us a deeper understanding of the interaction between geosphere and biosphere at this site in the future.

Huang, Chia-I.; Amann, Rudolf; Amend, Jan P.; Bach, Wolfgang; Brunner, Benjamin; Meyerdierks, Anke; Price, Roy E.; Schubotz, Florence; Summons, Roger; Wenzhfer, Frank

2010-05-01

137

Iroquois/Tennessee and Champlain Pipeline Projects. Draft Environmental Impact Statement Regional System Alternatives. Volume 2.  

National Technical Information Service (NTIS)

The volume is Volume II for each of two environmental impact statements. These EISs are for the Champlain Pipeline Project and the Iroquois/Tennessee Pipeline Project, and are being issued concurrently. Volume II contains the environmental analysis of maj...

1989-01-01

138

Lake  

ERIC Educational Resources Information Center

The lake is blue black and deep. It is a glaciated finger lake, clawed out of rock when ice retracted across Nova Scotia in a northerly direction during the last ice age. The lake is narrow, a little over a mile long, and deep, 90 to 190 feet in places according to local lore, off the charts in others. The author loves to swim there, with a sense

Wien, Carol Anne

2008-01-01

139

Palaeomagnetism and rock-magnetism results from Lake Albano and the central Adriatic Sea (Italy)  

Microsoft Academic Search

Magnetic measurements have included whole core susceptibility scans, detailed rock magnetic characterisation of catchment materials and lake sediments, and palaeomagnetic measurements. The susceptibility scans on cores from Lake Albano and Lake Nemi have pro- vided an essential part of the initial stratigraphic information upon which core selection for subsequent detailed studies of the lake sediments were made. They also shed

Tim C. ROLPH; Frank OLDFIELD; Kuno D. VAN DER POST

140

Interannual variation of persistent organic pollutants over the Great Lakes induced by tropical Pacific sea surface temperature anomalies  

NASA Astrophysics Data System (ADS)

The linkage between decadal monitored air concentrations of persistent organic pollutants (POPs) around the Great Lakes from 1992 to 2002 and the sea surface temperature anomalies (SSTA) in the tropical Pacific was studied on a year-to-year basis. It is shown that interannual fluctuation of air concentrations of ?-hexachlorocyclohexane (?-HCH), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) measured in the Great Lakes basin in spring and summer are highly correlated with the tropical Pacific SSTA. Spatial correlation patterns between the air concentrations of POPs over the Great Lakes and SSTA exhibit a feature of the characteristic SST signature associated with the occurrence of an El Nio event and SSTA forcing in atmospheric circulation teleconnections. The relations between air concentration of these POPs and the tropical Pacific SSTA are consistent with the response of midlatitude atmospheric circulation to the Pacific SSTA, showing that air concentration of the POPs in spring and summer seasons is related to tropical Pacific SSTA in preceding winter and spring months. The up to 6 month lag response of the POP air concentration to the SSTA provides a basis for forecasting the temporal trend of POPs in the atmosphere over the Great Lakes basin. The connection of the SSTA and the changes in the POP air concentration with the atmospheric circulation suggests that the atmospheric circulation associated with the tropical Pacific sea surface temperature (SST) forcing plays a major role in the reemission of POPs from sources and long-range transport of POPs in the atmosphere.

Ma, Jianmin; Li, Yi-Fan

2006-02-01

141

Classifying sea lamprey marks on Great Lakes lake trout: observer agreement, evidence on healing times between classes and recommendations for reporting of marking statistics  

USGS Publications Warehouse

In 1997 and 1998 two workshops were held to evaluate how consistent observers were at classifying sea lamprey (Petromyzon marinus) marks on Great Lakes lake trout (Salvelinus namaycush) as described in the King classification system. Two trials were held at each workshop, with group discussion between trials. Variation in counting and classifying marks was considerable, such that reporting rates for A1-A3 marks varied two to three-fold among observers of the same lake trout. Observer variation was greater for classification of healing or healed marks than for fresh marks. The workshops highlighted, as causes for inconsistent mark classification, both departures from the accepted protocol for classifying marks by some agencies, and differences in how sliding and multiple marks were interpreted. Group discussions led to greater agreement in classifying marks. We recommend ways to improve the reliability of marking statistics, including the use of a dichotomous key to classify marks. Laboratory data show that healing times of marks on lake trout were much longer at 4A?C and 1A?C than at 10A?C and varied greatly among individuals. Reported A1-A3 and B1-B3 marks observed in late summer and fall collections likely result from a mixture of attacks by two year classes of sea lamprey. It is likely that a substantial but highly uncertain proportion of attacks that occur in late summer and fall lead to marks that are classified as A1-A3 the next spring. We recommend additional research on mark stage duration.

Ebener, Mark P.; Bence, James R.; Bergstedt, Roger A.; Mullet, Katherine M.

2003-01-01

142

Beryllium isotopes as tracers of Lake Lisan (last Glacial Dead Sea) hydrology and the Laschamp geomagnetic excursion  

NASA Astrophysics Data System (ADS)

The content of the cosmogenic isotope 10Be (t1/2=1.39 Ma) in lacustrine sediments that deposit in lakes with a large watershed is susceptible to both climate and cosmogenic production rate variations. In order to distinguish between these two controls, we measured 10Be and major elements in several sections of the annually laminated sediments of the Lake Lisan (the last Glacial precursor of the Dead Sea) that are composed of detrital sediments and primary (evaporitic) aragonites. The sections were selected to represent regional hydrology and climate as reflected by different lake configurations (level rise, drop and high-stands) and rapid change in the 10Be production rate during the Laschamp geomagnetic excursion. Since the short-lived cosmogenic sister of 10Be, 7Be (t1/2=53.3 d) has virtually no recycled component, the recycled 10Be in Lake Lisan detrital sediments was evaluated by measuring 7Be in their modern equivalents: modern flood suspended matter, dust and mud cracks. Our results demonstrate that although the recycled 10Be component is significant, secular variations in the 10Be concentration in Lake Lisan sediments correlate with hydrological variations and geomagnetic excursions. During periods of moderate variations in 10Be production rate, the 10Be concentration in the Lisan detrital sediments positively correlates with lake level, Al + Fe content and the (Al + Fe)/(Ca + Mg) ratio. These correlations suggest that the 10Be is adsorbed on the fine silicate component (probably clays) of the detrital laminae. The fine silicates together with carbonates were transported to Dead Sea drainage basin mainly as airborne dust that after a short residence time was washed into Lake Lisan as flood suspended matter. We suggest that preferential dissolution of carbonates in the flood suspended matter concentrated the residual fine component leading to the positive correlation between 10Be and the (Al + Fe)/(Ca + Mg) ratio. During periods of increased water discharge more carbonates were dissolved and hence the 10Be concentration in the detrital laminae increased. During periods of rapid increase in the 10Be production rate (e.g. the Laschamp excursion), 10Be showed a ?2 fold increase, beyond the above-mentioned correlations (lake levels and Al + Fe contents). This observation suggests that Lake Lisan can serve as a potential high-resolution archive of 10Be production rate variations during periods of geomagnetic excursions.

Belmaker, Reuven; Stein, Mordechai; Beer, Jrg; Christl, Marcus; Fink, David; Lazar, Boaz

2014-08-01

143

The influence of neighbor relatedness on multilevel selection in the Great Lakes sea rocket.  

PubMed

Natural selection can operate at the individual and group level in natural populations. This study investigates the ecological factors that determine the relative importance of individual versus group selection. In particular, it determines how the relatedness of interacting neighbors influences multilevel natural selection in a population of the Great Lakes sea rocket. Focal plants were grown in groups of siblings, groups of plants that were themselves siblings but unrelated to the focal plants, and groups of plants with mixed genotypes. Significant group selection on plant size was observed only when the neighbors were siblings but not when they were unrelated. In sibling groups, individuals with heavier stems had higher fitness, and individuals growing with heavier but shorter neighbors also had higher fitness. Thus, individual and group selection on stem weight operated in the same direction. The detection of group selection in sibling groups can be attributed in part to an increased opportunity for group selection in these groups since sibling groups differed more from one another than the other group types. In addition, the quality of the selective environment in sibling groups may have differed from that for the other group types. Group selection was therefore more prevalent in the most genetically structured sample, in which responses to group selection are also most likely to occur. PMID:12856238

Donohue, Kathleen

2003-07-01

144

Relationship of length of fish to incidence of sea lamprey scars on white suckers, Catostomus commersoni, in Lake Huron  

USGS Publications Warehouse

During the course of experimental fishing operations conducted by the staff of Hammond Bay Fishery Laboratory (a field station of Great Lakes Fishery Investigations) in 1950-1951, length measurements and records of scarring incidence and number of scars per individual were obtained for a sample of 552 white suckers, Catostomus commersoni (Lacepede). The results of this study indicate that if information on the incidence of sea lamprey scars on white suckers is to be used to judge the relative abundance of sea lampreys and the damages inflicted by that parasite on the sucker stock, data must include records of the lengths of fish. It is to be suspected strongly that a similar conclusion applies in other localities and to other species preyed upon by the sea lamprey.

Hall, A.E.; Elliott, Oliver R.

1954-01-01

145

Concentrations of organotin compounds in various fish species in the Finnish lake waters and Finnish coast of the Baltic Sea.  

PubMed

Organotin compounds (OTCs) leaching from the antifouling paints used in boats and ships have contaminated many water areas worldwide. The purpose of this study was to obtain a general view of the organotin contamination in fish in Finnish lake areas and Finnish coast of the Baltic Sea using perch as the main indicator species. Perch sampling covered areas presumed as less contaminated and areas suspected as more contaminated. Besides perch, 12 other species were sampled from sites presumed as less contaminated. OTCs measured were mono-, di- and tributyltin, mono-, di-, and triphenyltin and dioctyltin. The sum concentration of OTCs (SigmaOTCs) in perch in the least contaminated areas of the Baltic Sea were around 20 ng/g fresh weight (fw) and less than 10 ng/g fw in lake areas. In heavily contaminated areas of the Baltic Sea 150-500 ng/g fw in perch were detected. In lake areas the maximum SigmaOTCs in perch was only 30 ng/g fw. With regard to the other species in the Baltic Sea, salmon, sprat, flounder, whitefish, vendace and lamprey contained low concentrations (SigmaOTCs mainly less than 20 ng/g fw), whereas in pike, pike-perch, burbot and bream concentrations were higher. SigmaOTCs in lake fish were generally lower than in the Baltic Sea. In a distance gradient study, SigmaOTCs in perch decreased quickly from nearly 200 ng/g fw at a contaminated harbor area to 35 ng/g fw during a distance of 5 km. Further decrease was slower and reached 15 ng/g fw at 100 km. In a size dependence study triphenyltin showed better correlation with the fish length than tributyltin for all species studied, i.e. for perch (0.16 vs 0.26), pike-perch (0.13 vs 0.24) and roach (0.46 vs 0.80). High correlation for roach may be partly explained by smaller number of samples collected and small length range. PMID:20303571

Rantakokko, Panu; Hallikainen, Anja; Airaksinen, Riikka; Vuorinen, Pekka J; Lappalainen, Antti; Mannio, Jaakko; Vartiainen, Terttu

2010-05-15

146

The Kitten Shipwreck: Archaeology and Reconstruction of a Black Sea Merchantman  

E-print Network

of this project. Without him, the excavation of the Kitten shipwreck would never have happened. I am much the richer for having met Dr. Crisman and for having studied under him! Without the educational experience of the 1998 field season in Lake Champlain, I... of this project. Without him, the excavation of the Kitten shipwreck would never have happened. I am much the richer for having met Dr. Crisman and for having studied under him! Without the educational experience of the 1998 field season in Lake Champlain, I...

Batchvarov, Kroum Nickolaev

2010-10-12

147

Lake and sea populations of Mysis relicta (Crustacea, Mysida) with different visual-pigment absorbance spectra use the same A1 chromophore.  

PubMed

Glacial-relict species of the genus Mysis (opossum shrimps) inhabiting both fresh-water lakes and brackish sea waters in northern Europe show a consistent lake/sea dichotomy in eye spectral sensitivity. The absorbance peak (?max) recorded by microspectrophotometry in isolated rhabdoms is invariably 20-30 nm red-shifted in "lake" compared with "sea" populations. The dichotomy holds across species, major opsin lineages and light environments. Chromophore exchange from A1 to A2 (retinal ? 3,4-didehydroretinal) is a well-known mechanism for red-shifting visual pigments depending on environmental conditions or stages of life history, present not only in fishes and amphibians, but in some crustaceans as well. We tested the hypothesis that the lake/sea dichotomy in Mysis is due to the use of different chromophores, focussing on two populations of M. relicta from, respectively, a Finnish lake and the Baltic Sea. They are genetically very similar, having been separated for less than 10 kyr, and their rhabdoms show a typical lake/sea difference in ?max (554 nm vs. 529 nm). Gene sequencing has revealed no differences translating into amino acid substitutions in the transmembrane parts of their opsins. We determined the chromophore identity (A1 or A2) in the eyes of these two populations by HPLC, using as standards pure chromophores A1 and A2 as well as extracts from bovine (A1) and goldfish (A2) retinas. We found that the visual-pigment chromophore in both populations is A1 exclusively. Thus the spectral difference between these two populations of M. relicta is not due to the use of different chromophores. We argue that this conclusion is likely to hold for all populations of M. relicta as well as its European sibling species. PMID:24516590

Belikov, Nikolai; Yakovleva, Marina; Feldman, Tatiana; Demina, Olga; Khodonov, Andrei; Lindstrm, Magnus; Donner, Kristian; Ostrovsky, Mikhail

2014-01-01

148

Lake and Sea Populations of Mysis relicta (Crustacea, Mysida) with Different Visual-Pigment Absorbance Spectra Use the Same A1 Chromophore  

PubMed Central

Glacial-relict species of the genus Mysis (opossum shrimps) inhabiting both fresh-water lakes and brackish sea waters in northern Europe show a consistent lake/sea dichotomy in eye spectral sensitivity. The absorbance peak (?max) recorded by microspectrophotometry in isolated rhabdoms is invariably 2030 nm red-shifted in lake compared with sea populations. The dichotomy holds across species, major opsin lineages and light environments. Chromophore exchange from A1 to A2 (retinal ? 3,4-didehydroretinal) is a well-known mechanism for red-shifting visual pigments depending on environmental conditions or stages of life history, present not only in fishes and amphibians, but in some crustaceans as well. We tested the hypothesis that the lake/sea dichotomy in Mysis is due to the use of different chromophores, focussing on two populations of M. relicta from, respectively, a Finnish lake and the Baltic Sea. They are genetically very similar, having been separated for less than 10 kyr, and their rhabdoms show a typical lake/sea difference in ?max (554 nm vs. 529 nm). Gene sequencing has revealed no differences translating into amino acid substitutions in the transmembrane parts of their opsins. We determined the chromophore identity (A1 or A2) in the eyes of these two populations by HPLC, using as standards pure chromophores A1 and A2 as well as extracts from bovine (A1) and goldfish (A2) retinas. We found that the visual-pigment chromophore in both populations is A1 exclusively. Thus the spectral difference between these two populations of M. relicta is not due to the use of different chromophores. We argue that this conclusion is likely to hold for all populations of M. relicta as well as its European sibling species. PMID:24516590

Belikov, Nikolai; Yakovleva, Marina; Feldman, Tatiana; Demina, Olga; Khodonov, Andrei; Lindstrom, Magnus; Donner, Kristian; Ostrovsky, Mikhail

2014-01-01

149

Quantification of a male sea lamprey pheromone in tributaries of Laurentian Great Lakes by liquid chromatography-tandem mass spectrometry.  

PubMed

We developed an assay for measuring 7?,12?,24-trihydroxy-5a-cholan-3-one-24-sulfate (3kPZS), a mating pheromone released by male sea lampreys (Petromyzon marinus), at low picomolar concentrations in natural waters to assess the presence of invasive populations. 3kPZS was extracted from streamwater at a rate of recovery up to 90% using a single cation-exchange and reversed-phase mixed-mode cartridge, along with [(2)H(5)]3kPZS as an internal standard, and quantified using ultrahigh performance liquid chromatography-tandem mass spectrometry. The limit of detection was below 0.1 ng L(-1) (210 fM), which was the lowest concentration tested. Intra- and interday coefficients of variation were between 0.3-11.6% and 4.8-9.8%, respectively, at 1 ng 3kPZS L(-1) and 5 ng 3kPZS L(-1). This assay was validated by repeat measurements of water samples from a stream spiked with synthesized 3kPZS to reach 4.74 ng L(-1) or 0.24 ng L(-1). We further verified the utility of this assay to detect spawning populations of lampreys; in the seven tributaries to the Laurentian Great Lakes sampled, 3kPZS concentrations were found to range between 0.15 and 2.85 ng L(-1) during the spawning season in known sea lamprey infested segments and were not detectable in uninfested segments. The 3kPZS assay may be useful for the integrated management of sea lamprey, an invasive species in the Great Lakes where pheromone-based control and assessment techniques are desired. PMID:21711046

Xi, Xiaodan; Johnson, Nicholas S; Brant, Cory O; Yun, Sang-Seon; Chambers, Keali L; Jones, A Daniel; Li, Weiming

2011-08-01

150

The New Zealand mud snail Potamopyrgus antipodarum (Gray, 1843) is colonising the artificial lakes of Kaliningrad City, Russia (Baltic Sea Coast)  

Microsoft Academic Search

In 2008, the New Zealand mud snail Potamopyrgus antipodarum was detected in artificial freshwater lakes of Kalinigrad City (Russia), developed in sand and gravel extraction sites. P. antipodarum records along the Baltic coast were previously located in open sea and estuary sites and this is first species' record, in this type of man-made freshwater habitat, for the Baltic Region.

Dmitry Filippenko; Thaddeus K. Graczyk; Mikhail O. Son

2008-01-01

151

Passage of four teleost species prior to sea lamprey (Petromyzon marinus) migration in eight tributaries of Lake Superior, 1954 to 1979  

USGS Publications Warehouse

Seasonally operated barriers in rivers are used by the Great Lakes Fishery Commission to block adult sea lamprey (Petromyzon marinus) migrations, yet pass other fish during some part of the year. Knowledge of the overlap of spawning migrations of sea lampreys and other fish species are vital for the efficient operation of the Commission's barrier program. The migration of sea lamprey spawners was compared with the migration of four other fish species using trap captures at electric barriers on eight Lake Superior tributaries during 1954 to 1979. The passage of rainbow trout (Oncorhynchus mykiss), rainbow smelt (Osmerus mordax), longnose suckers (Catostomus catostomus), and white suckers (Catostomus commersoni) prior to the capture of sea lampreys was quantified as the proportion of the annual catch of each species. Average passage over all streams and years was smallest (5%) for longnose sucker and largest (21%) for rainbow smelt. Passage prior to first sea lamprey catch was significantly different among rivers for all four species and significantly different among years for rainbow trout. Much of the variability in annual passage was unexplained by river or year effects. It is suggested that stream-specific information on run times of sea lampreys and other fishes be used to define timing of seasonal barrier operations. If barrier operations are timed to block the entire sea lamprey spawning run, then fish passage devices are needed to pass rainbow trout, rainbow smelt, longnose suckers, and white suckers.

Klingler, G. L.; Adams, J. V.; Heinrich, J. W.

2003-01-01

152

Passage of four teleost species prior to sea lamprey (Petromyzon marinus) migration in eight tributaries of Lake Superior, 1954-1979  

USGS Publications Warehouse

Seasonally operated barriers in rivers are used by the Great Lakes Fishery Commission to block adult sea lamprey (Petromyzon marinus) migrations, yet pass other fish during some part of the year. Knowledge of the overlap of spawning migrations of sea lampreys and other fish species are vital for the efficient operation of the Commission's barrier program. The migration of sea lamprey spawners was compared with the migration of four other fish species using trap captures at electric barriers on eight Lake Superior tributaries during 1954 to 1979. The passage of rainbow trout (Oncorhynchus mykiss), rainbow smelt (Osmerus mordax), longnose suckers (Catostomus catostomus), and white suckers (Catostomus commersoni) prior to the capture of sea lampreys was quantified as the proportion of the annual catch of each species. Average passage over all streams and years was smallest (5%) for longnose sucker and largest (21%) for rainbow smelt. Passage prior to first sea lamprey catch was significantly different among rivers for all four species and significantly different among years for rainbow trout. Much of the variability in annual passage was unexplained by river or year effects. It is suggested that stream-specific information on run times of sea lampreys and other fishes be used to define timing of seasonal barrier operations. If barrier operations are timed to block the entire sea lamprey spawning run, then fish passage devices are needed to pass rainbow trout, rainbow smelt, longnose suckers, and white suckers.

Klinger, Gregory L.; Adams, Jean V.; Heinrich, John W.

2003-01-01

153

Fauna and flora in submarine early Holocene lake-marl deposits from the southwestern Baltic Sea  

Microsoft Academic Search

Studies of plant and animal macrofossils have been carried out on early-Holocene lake marls from the southwestern Baltic. The records have been dated to the interval from c. 8500 to 7800 14C years BP by correlating pollen assemblages to an onshore radiocarbon dated pollen diagram. The sediments contain from 5 to 81% carbonate, and only few macroscopic remains of wetland

Ole Bennike; Wolfram Lemke; Jrn Bo Jensen

1998-01-01

154

Impact of Lake Okeechobee Sea Surface Temperatures on Numerical Predictions of Summertime Convective Systems over South Florida  

NASA Technical Reports Server (NTRS)

The NASA Short-term Prediction Research and Transition (SPoRT) Center, the Florida Institute of Technology, and the NOAA/NWS Weather Forecast Office at Miami, FL (MFL) are collaborating on a project to investigate the impact of using high-resolution, 2-km Moderate Resolution Imaging Spectroradiometer (MODIS) sea surface temperature (SST) composites within the Weather Research and Forecasting (WRF) prediction system. The NWS MFL is currently running WRF in real-time to support daily forecast operations, using the National Centers for Environmental Prediction Nonhydrostatic Mesoscale Model dynamical core within the NWS Science and Training Resource Center's Environmental Modeling System (EMS) software. Twenty-seven hour forecasts are run daily initialized at 0300, 0900, 1500, and 2100 UTC on a domain with 4-km grid spacing covering the southern half of Florida and adjacent waters of the Gulf of Mexico and Atlantic Ocean. The SSTs are initialized with the NCEP Real-Time Global (RTG) analyses at 1/12deg resolution. The project objective is to determine whether more accurate specification of the lower-boundary forcing over water using the MODIS SST composites within the 4-km WRF runs will result in improved sea fluxes and hence, more accurate e\\olutiono f coastal mesoscale circulations and the associated sensible weather elements. SPoRT conducted parallel WRF EMS runs from February to August 2007 identical to the operational runs at NWS MFL except for the use of MODIS SST composites in place of the RTG product as the initial and boundary conditions over water. During the course of this evaluation, an intriguing case was examined from 6 May 2007, in which lake breezes and convection around Lake Okeechobee evolved quite differently when using the high-resolution SPoRT MODIS SST composites versus the lower-resolution RTG SSTs. This paper will analyze the differences in the 6 May simulations, as well as examine other cases from the summer 2007 in which the WRF-simulated Lake Okeechobee breezes evolved differently due to the SST initialization. The effects on wind fields and precipitation systems will be emphasized, including validation against surface mesonet observations and Stage IV precipitation grids.

Case, Jonathan L.; Splitt, Michael E.; Fuell, Kevin K.; Santos, Pablo; Lazarus, Steven M.; Jedlovec, Gary J.

2009-01-01

155

New insights into North America-Pacific Plate boundary deformation from Lake Tahoe, Salton Sea and southern Baja California  

NASA Astrophysics Data System (ADS)

Five studies along the Pacific-North America (PA-NA) plate boundary offer new insights into continental margin processes, the development of the PA-NA tectonic margin and regional earthquake hazards. This research is based on the collection and analysis of several new marine geophysical and geological datasets. Two studies used seismic CHIRP surveys and sediment coring in Fallen Leaf Lake (FLL) and Lake Tahoe to constrain tectonic and geomorphic processes in the lakes, but also the slip-rate and earthquake history along the West Tahoe-Dollar Point Fault. CHIRP profiles image vertically offset and folded strata that record deformation associated with the most recent event (MRE). Radiocarbon dating of organic material extracted from piston cores constrain the age of the MRE to be between 4.1--4.5 k.y. B.P. Offset of Tioga aged glacial deposits yield a slip rate of 0.4--0.8 mm/yr. An ancillary study in FLL determined that submerged, in situ pine trees that date to between 900-1250 AD are related to a medieval megadrought in the Lake Tahoe Basin. The timing and severity of this event match medieval megadroughts observed in the western United States and in Europe. CHIRP profiles acquired in the Salton Sea, California provide new insights into the processes that control pull-apart basin development and earthquake hazards along the southernmost San Andreas Fault. Differential subsidence (>10 mm/yr) in the southern sea suggests the existence of northwest-dipping basin-bounding faults near the southern shoreline. In contrast to previous models, the rapid subsidence and fault architecture observed in the southern part of the sea are consistent with experimental models for pull-apart basins. Geophysical surveys imaged more than 15 N15E oriented faults, some of which have produced up to 10 events in the last 2-3 kyr. Potentially 2 of the last 5 events on the southern San Andreas Fault (SAF) were synchronous with rupture on offshore faults, but it appears that ruptures on three offshore faults are synchronous with Colorado River diversions into the basin. The final study was used coincident wide-angle seismic refraction and multichannel seismic reflection surveys that spanned the width of the of the southern Baja California (BC) Peninsula. The data provide insight into the spatial and temporal evolution of the BC microplate capture by the Pacific Plate. Seismic reflection profiles constrain the upper crustal structure and deformation history along fault zone on the western Baja margin and in the Gulf of California. Stratal divergence in two transtensional basins along the Magdalena Shelf records the onset of extension across the Tosco-Abreojos and Santa Margarita faults. We define an upper bound of 12 Ma on the age of the pre-rift sediments and an age of 8 Ma for the onset of extension. Tomographic imaging reveals a very heterogeneous upper crust and a narrow, high velocity zone that extends 40 km east of the paleotrench and is interpreted to be remnant oceanic crust.

Brothers, Daniel Stephen

156

Evidence for allochthonous prey delivery to Lake Michigan's Mid-Lake Reef Complex: Are deep reefs analogs to oceanic sea mounts?  

Microsoft Academic Search

Lake Michigan's Sheboygan Reef is contained in a refuge for lake trout (Salvelinus namaycush) restoration, and is one of several deep midlake reefs that historically were productive spawning and fishery grounds. The summits of these reefs are rocky and deeper than the photic zone. We propose that the basis of trophic support for lake trout and their prey is allochthonous

Christopher J. Houghton; Charles R. Bronte; Robert W. Paddock; John Janssen

2010-01-01

157

Optimizing larval assessment to support sea lamprey control in the Great Lakes  

USGS Publications Warehouse

Elements of the larval sea lamprey (Petromyzon marinus) assessment program that most strongly influence the chemical treatment program were analyzed, including selection of streams for larval surveys, allocation of sampling effort among stream reaches, allocation of sampling effort among habitat types, estimation of daily growth rates, and estimation of metamorphosis rates, to determine how uncertainty in each element influenced the stream selection program. First, the stream selection model based on current larval assessment sampling protocol significantly underestimated transforming sea lamprey abundance, transforming sea lampreys killed, and marginal costs per sea lamprey killed, compared to a protocol that included more years of data (especially for large streams). Second, larval density in streams varied significantly with Type-I habitat area, but not with total area or reach length. Third, the ratio of larval density between Type-I and Type-II habitat varied significantly among streams, and that the optimal allocation of sampling effort varied with the proportion of habitat types and variability of larval density within each habitat. Fourth, mean length varied significantly among streams and years. Last, size at metamorphosis varied more among years than within or among regions and that metamorphosis varied significantly among streams within regions. Study results indicate that: (1) the stream selection model should be used to identify streams with potentially high residual populations of larval sea lampreys; (2) larval sampling in Type-II habitat should be initiated in all streams by increasing sampling in Type-II habitat to 50% of the sampling effort in Type-I habitat; and (3) methods should be investigated to reduce uncertainty in estimates of sea lamprey production, with emphasis on those that reduce the uncertainty associated with larval length at the end of the growing season and those used to predict metamorphosis.

Hansen, Michael J.; Adams, Jean V.; Cuddy, Douglas W.; Richards, Jessica M.; Fodale, Michael F.; Larson, Geraldine L.; Ollila, Dale J.; Slade, Jeffrey W.; Steeves, Todd B.; Young, Robert J.; Zerrenner, Adam

2003-01-01

158

Yangtze Delta, China: Taihu lake-level variation since the 1950s, response to sea-level rise and human impact  

Microsoft Academic Search

Hydrological records collected from water gauge stations since the 1950s demonstrate that the Taihu lake level is rising.\\u000a The average rate of the lake-level rise is 0.41.1?mm\\/year during the non-flood season, resulting directly from a rise in\\u000a sea level. High rates of 3.05.0?mm\\/year of rise are even recorded during the wet season. This indicates increasing human\\u000a activities such as reclamation,

Z. Y. Chen; Z. H. Wang

1999-01-01

159

Linear, one-dimensional models of the surface and internal standing waves for a long and narrow lake  

NASA Astrophysics Data System (ADS)

Linear, one-dimensional, analytical, and numerical models for seiches (standing waves) existing at the surface and on the internal interface between the upper warm and bottom cold layers for a long, narrow lake are developed. Using the specific bathymetric and thermal structures of a lake, Lake Champlain, these models predict the periods, nodal locations, vertical displacements, and current velocities associated with the fundamental and higher-order modes. Modeled results are compared with historical limnological data obtained from Lake Champlain. Agreement is good for the periods of the first few modes of the surface and internal seiches; however, predicted current velocities associated with the internal seiche are about half as large as those actually observed.

Prigo, Robert B.; Manley, T. O.; Connell, Benjamin S. H.

1996-03-01

160

Polychlorinated dibenzo- p-dioxins, dibenzofurans, biphenyls, naphthalenes and polybrominated diphenyl ethers in the edible fish caught from the Baltic Sea and lakes in Finland  

Microsoft Academic Search

A total of 156 fish composite samples were collected from five areas of the Baltic Sea and from three lakes and analysed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD\\/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polybrominated diphenyl ethers (PBDEs). The European Union's maximum permissible level for PCDD\\/Fs, 4pg WHO-TEQ\\/g fresh weight (fw), was exceeded in salmon, river lamprey and Baltic

Pirjo Isosaari; Anja Hallikainen; Hannu Kiviranta; Pekka J. Vuorinen; Raimo Parmanne; Jaana Koistinen; Terttu Vartiainen

2006-01-01

161

Variability in ice phenology on Great Bear Lake and Great Slave Lake, Northwest Territories, Canada, from SeaWinds\\/QuikSCAT: 20002006  

Microsoft Academic Search

The temporal evolution of the backscatter coefficient, sigma-nought (?) from QuikSCAT was evaluated for monitoring ice phenology on Great Bear Lake (66N, 121W) and Great Slave Lake (6140?N, 114W), Northwest Territories, Canada. Results indicated that ? from QuikSCAT can be used to detect melt onset, water clear of ice and freeze onset dates on both lakes. An ice phenology algorithm

Stephen E. L. Howell; Laura C. Brown; Kyung-Kuk Kang; Claude R. Duguay

2009-01-01

162

Evaluation of strategies for the release of male sea lampreys (Petromyzon marinus) in Lake Superior for a proposed sterile-male-release program  

USGS Publications Warehouse

Successful implementation of a sea lamprey (Petromyzon marinus) control technique that uses sterilized males to reduce reproduction presently depends on the importation of large numbers of males outside of the target population. Strategies were examined for releasing male sea lampreys from Lakes Michigan and Huron into the Lake Superior spawning population and the ability of these introduced males to compete with resident males and spawn with resident females. During 1987, 553 (9%) of 6,324 imported fertile males released at 12 shoreline and one offshore site in Lake Superior were recaptured. Most remained within 20 km of the release site and entered the first stream encountered. During 1988, 393 (18%) of 2,208 imported fertile males released directly into three spawning rivers were recaptured. In both cases, animals released early during the spawning run were more likely to be recaptured than those released later. Introduced males successfully competed with resident males and spawned with resident females. Demonstrating that male sea lampreys could reproduce successfully when relocated supported subsequent large-scale field trials of the sterile-male-release technique.

Kaye, C. A.; Heinrich, J. W.; Hanson, L. H.; McDonald, R. B.; Slade, J. W.; Genovese, J. H.; Swink, W. D.

2003-01-01

163

Philipsburg Plattsburgh  

E-print Network

AdirondackM ountains Green Mountains Lake Champlain Lake George QU?BEC Champlain Canal VERMONTNEWYORK Richelieu River FIGURE 1 | THE LAKE CHAMPLAIN BASIN OR WATERSHED ABOUTTHE LAKE CHAMPLAIN BASIN PROGRAM The Lake Champlain Basin Program (LCBP) was created by the Lake Champlain Special Designation Act of 1990

Hayden, Nancy J.

164

Lake classification in Vermont  

NASA Technical Reports Server (NTRS)

In order to comply with the Federal Clean Water Act and, in so doing, develop a procedure to periodically update the classification, the State of Vermont evaluated the ability of LANDSAT to detect general water quality and specific water quality parameters in Vermont lakes. Unsupervised and supervised classifications as well as regression analyses were used to examine LANDSAT data from Lake Champlain and from four small nearby lakes. Unsupervised and supervised classifications were found to be of somewhat limited value. Regression analyses revealed a good correlation between depth-integrated total phosphorus concentrations and LANDSAT band 4 data (r2= 0.92) and between Secchi disk transparencies and LANDSAT band 4 data (r2 - 0.85). No correlation was found between depth-integrated chlorophyll-a samples and LANDSAT data. Vermont is expanding this LANDSAT evaluation to include the remaining lakes in the state greater than twenty acres and steps are being taken to incorporate LANDSAT into the state's ongoing water quality monitoring programs.

Garrison, V.; Bryant, N.

1981-01-01

165

Heavy metal pollution status in surface sediments of Swan Lake lagoon and Rongcheng Bay in the northern Yellow Sea.  

PubMed

The national 'Shandong Peninsula Blue Economic Zone Development Plan' compels the further understanding of the distribution and potential risk of metals pollution in the east coast of China, where the rapid economic and urban development have been taken off and metal pollution has become a noticeable problem. Surface sediments collected from the largest swan habitat in Asia, the Swan Lake lagoon and the surrounding coastal area in Rongcheng Bay in northern Yellow Sea, were analyzed for the total metal concentrations and chemical phase partitioning of five heavy metals (Cu, Zn, Pb, Cd, and Cr). Metal contents in the studied region have increased significantly in the past decade. The speciation analyzed by the sequential extraction showed that Zn and Cr were present dominantly in the residual fraction and thus of low bioavailability, while Cd, Pb and Cu were found mostly in the non-residual fraction thus of high potential availability, indicating significant anthropogenic sources. Among the five metals, Cd is the most outstanding pollutant and presents high risk, and half of the surface sediments in the studied region had a 21% probability of toxicity based on the mean Effect Range-Median Quotient. At some stations with comparable total metal contents, remarkably different non-residual fraction portions were determined, pointing out that site-specific risk assessment integrating speciation is crucial for better management practices of coastal sediments. PMID:23880240

Huang, Lili; Pu, Xinming; Pan, Jin-Fen; Wang, Bo

2013-11-01

166

Concentrations of mercury and metals in the microlayer and sub-surface water of two large lakes  

SciTech Connect

In previous investigations, pollutant concentrations in surface microlayers have been reported to be elevated over those in the sub-surface water. The reasons for this enrichment are many, and include atmospheric deposition, fluvial inputs and oil spills. The objective of this study was to investigate the role that atmospheric deposition plays in the enrichment of mercury and trace metals in the microlayer of Lakes Champlain and Michigan. A secondary objective was to compare the microlayer and sub-surface concentrations of metals. Samples of air, microlayer and sub-surface water were collected using ultra-clean techniques during the summer of 1993. Lake Champlain samples were collected on mile from Burlington, VT while Lake Michigan samples were collected four miles from Chicago, IL. Mercury samples were analyzed in a class 100 clean room at the University of Michigan by dual amalgamation and CVAFS and metals wee analyzed by ICPMS. Results from the field investigations include: (1) Lake Michigan samples had higher average concentrations of mercury and other metals than Lake Champlain; (2) Mercury levels varied more than the other metals for both lakes; (3) Atmospheric deposition may be responsible for elevated concentrations of certain metals such as zinc and cadmium in the microlayer during days when there is transport from adjacent urban areas.

Cleckner, L.B.; Esseks, E.S.; Meier, P.G.; Keeler, G.J. [Univ. of Michigan, Ann Arbor, MI (United States)

1994-12-31

167

Flathead Lake Lake Pend Oreille  

E-print Network

Flathead Lake Lake Pend Oreille Priest Lake Lake Koocanusa Hungry Horse Reservoir Coeur d'Alene Lake Dworshak Reservoir McDonald Lake Noxon Reservoir Swan Lake Hayden Lake St. Mary Lake Ashley Lake Whitefish Lake St. Mary Lake Cabinet Reservoir Kintla Lake Little Bitterroot Lake Duck Lake Bull Lake Bowman

168

Effects of environmental mercury on gonadal function in Lake Champlain northern pike (Esox lucius)  

SciTech Connect

Levels of mercury in the environment have increased steadily over the past two centuries, primarily because of human activity. Common point sources of this heavy metal include industrial waste discharge from chloralkali and paper pulp plants. More diffuse emissions, which become widely distributed by global wind currents, result from the combustion of fossil fuels and incineration of municipal wastes. Stricter laws in the United States have decreased the amount of pollution from point sources. In contrast, mercury from diffuse atmospheric origins has been increasing, causing a rise in rainwater concentrations and aquatic environments frequently distant from the source of pollution. Once in aquatic systems, mercury is readily converted to the more toxic methylated form and is the only heavy metal that indisputably biomagnifies through the food web. Acid rain compounds the environmental impact of anthropogenic mercury because aquatic organisms concentrate more mercury when living in waters with lower alkalinity. The persistence of this heavy metal in teleosts is illustrated by the finding that mercury, unlike cadmium, arsenic, and lead, did not decrease in North American freshwater fish between 1976 and 1984.

Friedmann, A.S.; Leiter, J.C. [Dartmouth Medical School, Lebanon, NH (United States)] [Dartmouth Medical School, Lebanon, NH (United States); Watzin, M.C. [Univ. of Vermont, Burlington, VT (United States)] [and others] [Univ. of Vermont, Burlington, VT (United States); and others

1996-03-01

169

The Eagle: an American brig on Lake Champlain during the War of 1812  

E-print Network

5. The burning of the Essex. By the 4th of August the British were back in Canada, laden to the gunnels with the spoils of war. For the officers, soldiers and sailors at Isle aux Noix, the week's work was entirely satisfying: U. S. Government... 5. The burning of the Essex. By the 4th of August the British were back in Canada, laden to the gunnels with the spoils of war. For the officers, soldiers and sailors at Isle aux Noix, the week's work was entirely satisfying: U. S. Government...

Crisman, Kevin James

2012-06-07

170

Deposition and watershed processing of mercury in the Lake Champlain basin  

SciTech Connect

Daily wet-only precipitation, weekly 24-hour vapor and particulate matter, snowmelt and stream water have been analyzed for total mercury (Hg) in Underhill, VT since December, 1992. Total Hg in precipitation ranged from 1.2-35 ng/L, with maximum concentrations occurring during summer. Vapor phase Hg ranged from 1.2 to 4.2 ng/m, with little annual variability, and particulate phase Hg ranged from 1 to 43 pg/m{sup 3}, with maximum concentrations in winter. Wet-only deposition of total Hg in precipitation totaled 9.26 {mu}g/m{sup 2} in 1993 and 7.66 {mu}g/m{sup 2} in 1994. Total Hg concentrations in a stream in our research watershed were 1-3 ng/L during base flow, and reached 79 ng/L at peak flow during spring snowmelt. Dissolved Hg concentrations were approximately 2 ng/L, even during peak flows, suggesting suspended Hg-containing sediments caused the high total Hg during peak flows. Synoptic sampling of larger streams in the drainage basin also showed significant Hg enrichment during snowmelt. Limited snowpack melt measurements indicated that Hg concentration and dissolved proportion in melt water were dynamic, varying with temperature and melting rate.

Scherbatskoy, T. [Univ. of Vermont, Burlington, VT (United States); Rea, A.; Keeler, G. [Univ. of Michigan, Ann Arbor, MI (United States)

1995-12-31

171

Erie Times-NIE/Great Lakes Sea Grant Network Dose of Reality: Remedies to keep everyday chemicals  

E-print Network

aquatic environment & how you can help protect this vital natural resource. A healthy Great Lakes benefits people, places, wildlife & the economy. You can help protect the environment & ecosystem of the Great Lakes region

Learn About The Great Lakes

2009-01-01

172

Lakes of the Huron basin: their record of runoff from the laurentide ice sheet  

NASA Astrophysics Data System (ADS)

The 189,000 km2 Huron basin is central in the catchment area of the present Laurentian Great Lakes that now drain via the St. Lawrence River to the North Atlantic Ocean. During deglaciation from 21-7.5 ka BP, and owing to the interactions of ice margin positions, crustal rebound and regional topography, this basin was much more widely connected hydrologically, draining by various routes to the Gulf of Mexico and Atlantic Ocean, and receiving overflows from lakes impounded north and west of the Great Lakes-Hudson Bay drainage divide. Early ice-marginal lakes formed by impoundment between the Laurentide Ice Sheet and the southern margin of the basin during recessions to interstadial positions at 15.5 and 13.2 ka BP. In each of these recessions, lake drainage was initially southward to the Mississippi River and Gulf of Mexico. In the first recession, drainage subsequently switched eastward along the ice margin to the North Atlantic Ocean. In the second recession, drainage continued southward through the Michigan basin, and later, eastward via the Ontario basin and Mohawk River valley to the North Atlantic Ocean. During the final retreat of ice in the Huron basin from 13 to 10 ka BP, proglacial lake drainage switched twice from the Michigan basin and the Mississippi River system to the North Atlantic via the Ontario basin and Mohawk River valley, finally diverting to the Champlain Sea in the St. Lawrence River valley at about 11.6 ka BP. New seismo- and litho-stratigraphic information with ostracode data from the offshore lacustrine sediments were integrated with the traditional data of shorelines, uplift histories of outlets, and radio-carbon-dated shallow-water evidence of transgressions and regressions to reconstruct the water level history and paleolimnological record for the northern Huron basin for the 11-7 ka BP period. Negative excursions in the ?18O isotopic composition of ostracodes and bivalves in southern Lake Michigan, southwestern Lake Huron and eastern Lake Erie indicate an influx of water from ice-marginal Lake Agassiz in central North America about 11 ka BP. A major decline in water levels of the Huron basin after 10.5 ka BP followed the high-level Main Lake Algonquin phase as ice receded and drainage was established through the North Bay area to Ottawa River valley. During the subsequent Mattawa-Stanley phase, the lake level history was dominated by fluctuations of tens of meters. Highstands of the earliest oscillations, whose origin is not clear, might be related to some of the well known Post Algonquin shorelines. After 9.6 ka BP, it is suggested that large inflows from Lake Agassiz and hydraulic damming in downstream outlets were the likely cause of the Lake Mattawa highstands. A lowstand at 9.3-9.1 ka BP occurred when these inflows were diverted, or impeded by an ice advance in the Nipigon basin area, while undiluted meltwater continued to enter the Huron basin. Assemblages and isotopic composition of the ostracode fauna indicate very dilute meltwater during the lowstands as late as 7.5 ka BP, and precipitation runoff with comparatively higher dissolved solids during the highstands. We speculate that the water composition of the Lake Mattawa highstands was dominated by the Agassiz inflows; by that time, much of Lake Agassiz was remote from ice-marginal environments, and the inflows were drawn from surface water of the southern sector of the lake, which was largely supplied by runoff and dissolved solids from the exposed land area of western Canada. Major inflows apparently ended about 8 ka BP, but northern proglacial lakes apparently continued as meltwater persisted in the Huron basin until about 7.5 ka BP. The cessation of major inflows initiated the final lowstand in the Huron basin and the present hydrological regime of local runoff.

Michael Lewis, C. F.; Moore, Theodore C.; Rea, David K.; Dettman, David L.; Smith, Alison M.; Mayer, Larry A.

173

@Sea  

NSDL National Science Digital Library

Describes the Harbor Branch Oceanographic Institution's at-sea research expeditions and presents both current and archived expeditions from 1999 to the present. Each expedition is described in a feature story with background, definitions, research technology and sampling equipment, maps, photos, daily logs, some videos and virtual tours, researcher profiles, and related links. HBOI scientists have studied maritime history, pharmaceuticals from the sea, sharks, behavior and physiology of marine life, marine sanctuaries and submersible technology.

174

Late Pleistocene glacial and lake history of northwestern Russia EILIV LARSEN, KURT H. KJR, IGOR N. DEMIDOV, SVEND FUNDER, KARI GRSFJELD, MICHAEL  

E-print Network

a huge ice-dammed lake formed in the White Sea basin (the `White Sea Lake'), only now the outlet across marine down-draw that led to its rapid collapse. The White Sea Lake drained into the Barents Sea

Ingólfsson, ?lafur

175

Low-head sea lamprey barrier effects on stream habitat and fish communities in the Great Lakes basin  

USGS Publications Warehouse

Low-head barriers are used to block adult sea lamprey (Petromyzon marinus) from upstream spawning habitat. However, these barriers may impact stream fish communities through restriction of fish movement and habitat alteration. During the summer of 1996, the fish community and habitat conditions in twenty-four stream pairs were sampled across the Great Lakes basin. Seven of these stream pairs were re-sampled in 1997. Each pair consisted of a barrier stream with a low-head barrier and a reference stream without a low-head barrier. On average, barrier streams were significantly deeper (df = 179, P = 0.0018) and wider (df = 179, P = 0.0236) than reference streams, but temperature and substrate were similar (df = 183, P = 0.9027; df = 179, P = 0.999). Barrier streams contained approximately four more fish species on average than reference streams. However, streams with low-head barriers showed a greater upstream decline in species richness compared to reference streams with a net loss of 2.4 species. Barrier streams also showed a peak in richness directly downstream of the barriers, indicating that these barriers block fish movement upstream. Using S??renson's similarity index (based on presence/absence), a comparison of fish community assemblages above and below low-head barriers was not significantly different than upstream and downstream sites on reference streams (n = 96, P > 0.05), implying they have relatively little effect on overall fish assemblage composition. Differences in the frequency of occurrence and abundance between barrier and reference streams was apparent for some species, suggesting their sensitivity to barriers.

Dodd, H. R.; Hayes, D. B.; Baylis, J. R.; Carl, L. M.; Goldstein, J. D.; McLaughlin, R. L.; Noakes, D. L. G.; Porto, L. M.; Jones, M. L.

2003-01-01

176

Halorhabdus tiamatea: proteogenomics and glycosidase activity measurements identify the first cultivated euryarchaeon from a deep-sea anoxic brine lake as potential polysaccharide degrader.  

PubMed

Euryarchaea from the genus Halorhabdus have been found in hypersaline habitats worldwide, yet are represented by only two isolates: Halorhabdus utahensis?AX-2(T) from the shallow Great Salt Lake of Utah, and Halorhabdus tiamatea?SARL4B(T) from the Shaban deep-sea hypersaline anoxic lake (DHAL) in the Red Sea. We sequenced the H.?tiamatea genome to elucidate its niche adaptations. Among sequenced archaea, H.?tiamatea features the highest number of glycoside hydrolases, the majority of which were expressed in proteome experiments. Annotations and glycosidase activity measurements suggested an adaptation towards recalcitrant algal and plant-derived hemicelluloses. Glycosidase activities were higher at 2% than at 0% or 5% oxygen, supporting a preference for low-oxygen conditions. Likewise, proteomics indicated quinone-mediated electron transport at 2% oxygen, but a notable stress response at 5% oxygen. Halorhabdus tiamatea furthermore encodes proteins characteristic for thermophiles and light-dependent enzymes (e.g. bacteriorhodopsin), suggesting that H.?tiamatea evolution was mostly not governed by a cold, dark, anoxic deep-sea habitat. Using enrichment and metagenomics, we could demonstrate presence of similar glycoside hydrolase-rich Halorhabdus members in the Mediterranean DHAL Medee, which supports that Halorhabdus species can occupy a distinct niche as polysaccharide degraders in hypersaline environments. PMID:24428220

Werner, Johannes; Ferrer, Manuel; Michel, Gurvan; Mann, Alexander J; Huang, Sixing; Juarez, Silvia; Ciordia, Sergio; Albar, Juan P; Alcaide, Mara; La Cono, Violetta; Yakimov, Michail M; Antunes, Andr; Taborda, Marco; da Costa, Milton S; Hai, Tran; Glckner, Frank Oliver; Golyshina, Olga V; Golyshin, Peter N; Teeling, Hanno

2014-08-01

177

Radium Isotopes as a Proxy for Groundwater Discharge and Residence Time in a Fresh Water Lake: Case Study From the Sea of Galilee, Israel  

NASA Astrophysics Data System (ADS)

During the past three decades radium isotopes have been extensively used to quantify the extent and the rate of groundwater discharge into coastal and estuarine environments, where fresh groundwater enters a more saline water body. One of the keys for the conservative behavior of radium in saline systems is the inverse dependence of its adsorption on salinity. In fresh groundwater radium is adsorbed, whereas in saline environment, the adsorbed radium is released to the aqueous phase. Here we examine an opposite scenario where saline groundwater discharges to a fresh water lake. We investigated the distribution of the radium isotope quartet in the Sea of Galilee (Cl~230 mg/l) and saline springs (Fuliya springs, Cl~2200 mg/l) that are considered to be the major salt source for the lake. Assuming that the saline springs of Fuliya represent the groundwater discharge to the lake, and that the measured radium activity in the lake is the residual of mixing, radioactive decay, and adsorption to bottom sediments and suspended particles, we conducted mass balance calculations for the different radium isotopes. Since the half-life of ^{226}Ra (1600 y) is higher than the average water residence time (5.8 y), we neglect the decay factor for this isotope. We use the differences in the ^{226}Ra/Cl ratios in the saline source (7.610-3) and the lake water (1.810-3) to calculate the relative depletion of ^{226}Ra in the lake water. The ^{226}Ra activity in the lake water ("Station A" in the center of the Sea of Galilee; ^{226}Ra=0.44 dmp/l) therefore represents only 24% of the groundwater ^{226}Ra flux, whereas 76% is lost from solution by adsorption. The activities of the short-lived ^{223}Ra (11.6 days) and ^{224}Ra (3.6 days) in the lake (410-4 and 5.910-3 dpm/l, respectively) represents only 2% and 4%, respectively, of the theoretical activities expected upon dilution. We show that the difference between the ^{224}Ra/^{223}Ra ratios in the lake (15.64) and the saline source (4.71) is identical to the ratio of the decay constants of ^{224}Ra and ^{223}Ra (3.1). Since the adsorption coefficients of the short-lived radium isotopes depend on their decay constants, ^{223}Ra with the longer half life would have selective higher adsorption. Assuming an identical residence time in the lake for ^{224}Ra and ^{223}Ra, we use the ratio of the decay constants of ^{224}Ra and ^{223}Ra to calculate the relative proportions of radium that is lost by adsorption and by decay. Our mass-balance results show that only a small fraction of ^{224}Ra and ^{223}Ra is adsorbed (1% and 24%), and a significant fraction is removed by radioactive decay with a residence time of ~23 days. The lack of significant sinks for the radium short- lived isotopes implies that they can be used to quantify saline groundwater fluxes also in freshwater lakes.

Raanan, H.; Vengosh, A.; Nishri, A.; Paytan, A.

2006-12-01

178

Aral Sea  

NASA Technical Reports Server (NTRS)

This series of MODIS images shows the dwindling Aral Sea. Once one of the world's largest freshwater lakes, the Aral Sea has decreased by as much as 60% over the past few decades due to diversion of the water to grow cotton and rice. These diversion have dropped the lake levels, increased salinity, and nearly decimated the fishing industry. The previous extent of the lake is clearly visible as a whitish perimeter in these image from April 16, May 18, and June 3, 2002. s. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

2002-01-01

179

Taconic foreland basin evolution: Sedimentology and cement stratigraphy of the Black River Group limestones in the Champlain Basin  

Microsoft Academic Search

The Black River Group (Middle Ordovician, Mohawkian Series) limestones in the Champlain Basin record the transition between the shallow deposits of the underlying Chazy Group limestones and the shale-limestone couplets of the overlying Trenton Group which record rapid deepening of the foreland basin. The Black River Group was deposited in a subsiding foreland basin during the early stages of the

S. C. Bechtel; C. J. Mehrtens

1993-01-01

180

In-Flight Validation of Mid and Thermal Infrared Remotely Sensed Data Using the Lake Tahoe and Salton Sea Automated Validation Sites  

NASA Technical Reports Server (NTRS)

The presentation includes an introduction, Lake Tahoe site layout and measurements, Salton Sea site layout and measurements, field instrument calibration and cross-calculations, data reduction methodology and error budgets, and example results for MODIS. Summary and conclusions are: 1) Lake Tahoe CA/NV automated validation site was established in 1999 to assess radiometric accuracy of satellite and airborne mid and thermal infrared data and products. Water surface temperatures range from 4-25C.2) Salton Sea CA automated validation site was established in 2008 to broaden range of available water surface temperatures and atmospheric water vapor test cases. Water surface temperatures range from 15-35C. 3) Sites provide all information necessary for validation every 2 mins (bulk temperature, skin temperature, air temperature, wind speed, wind direction, net radiation, relative humidity). 4) Sites have been used to validate mid and thermal infrared data and products from: ASTER, AATSR, ATSR2, MODIS-Terra, MODIS-Aqua, Landsat 5, Landsat 7, MTI, TES, MASTER, MAS. 5) Approximately 10 years of data available to help validate AVHRR.

Hook, Simon J.

2008-01-01

181

Lake Trout Mortality and Abundance in Southern Lake Huron  

Microsoft Academic Search

Populations of lake trout Salvelinus namaycush in the main basin of Lake Huron collapsed in the 1940s because of predation by sea lampreys Petromyzon marinus and commercial fishing. Efforts to rehabilitate lake trout have emphasized reduction of mortality and the stocking of hatchery-reared lake trout to reestablish populations. We fit a statistical catch-at-age model for lake trout in the southern

Shawn P. Sitar; James R. Bence; James E. Johnson; Mark P. Ebener; William W. Taylor

1999-01-01

182

Predicting minimum habitat characteristics for the Indiana bat in the Champlain Valley  

USGS Publications Warehouse

Predicting potential habitat across a landscape for rare species is extremely challenging. However, partitioned Mahalanobis D2 methods avoid pitfalls commonly encountered when surveying rare species by using data collected only at known species locations. Minimum habitat requirements are then determined by examining a principal components analysis to find consistent habitat characteristics across known locations. We used partitioned D 2 methods to examine minimum habitat requirements of Indiana bats (Myotis sodalis) in the Champlain Valley of Vermont and New York, USA, across 7 spatial scales and map potential habitat for the species throughout the same area. We radiotracked 24 female Indiana bats to their roost trees and across their nighttime foraging areas to collect habitat characteristics at 7 spatial scales: 1) roost trees, 2) 0.1-ha circular plots surrounding the roost trees, 3) home ranges, and 4-7) 0.5-km, 1-km, 2-km, and 3-km buffers surrounding the roost tree. Roost trees (n = 50) typically were tall, dead, large-diameter trees with exfoliating bark, located at low elevations and close to water. Trees surrounding roosts typically were smaller in diameter and shorter in height, but they had greater soundness than the roost trees. We documented 14 home ranges in areas of diverse, patchy land cover types that were close to water with east-facing aspects. Across all landscape extents, area of forest within roost-tree buffers and the aspect across those buffers were the most consistent features. Predictive maps indicated that suitable habitat ranged from 4.7-8.1% of the area examined within the Champlain Valley. These habitat models further understanding of Indiana bat summer habitat by indicating minimum habitat characteristics at multiple scales and can be used to aid management decisions by highlighting potential habitat. Nonetheless, information on juvenile production and recruitment is lacking; therefore, assessments of Indiana bat habitat quality in the region are still incomplete.

Watrous, K. S.; Donovan, T. M.; Mickey, R. M.; Darling, S. R.; Hicks, A. C.; Von Oettingen, S. L.

2006-01-01

183

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research  

E-print Network

's personal copy Exotic species in Lake Champlain J. Ellen Marsden a, , Michael Hauser b,1 a Rubenstein School: Invasion vector Canals Lake Champlain Great Lakes Exotic The Lake Champlain basin contains substantially recently (2008), the Asian clam was discovered two locks below Lake Champlain. The Lake Champlain canals

Marsden, Ellen

184

Laurance LakeLaurance Lake Lost LakeLost Lake  

E-print Network

Hood River Odell Parkdale Laurance LakeLaurance Lake Lost LakeLost Lake gler2frnh2hm owerdle2hm County #12;Hood River Odell Parkdale Laurance LakeLaurance Lake Lost LakeLost Lake gler2frnh2hm owerdle2. Zoning Data Source: Hood River County #12;Hood River Odell Parkdale Laurance LakeLaurance Lake Lost Lake

185

Threshold of wave generation on Titans lakes and seas: Effect of viscosity and implications for Cassini observations  

NASA Astrophysics Data System (ADS)

Motivated by radar and near-infrared data indicating that Titan's polar lakes are extremely smooth, we consider the conditions under which a lake surface will be ruffled by wind to form capillary waves. We evaluate laboratory data on wind generation and derive, without scaling for surface tension effects, a threshold for pure methane/ethane of 0.5-1 m/s. However, we compute the physical properties of predicted Titan lake compositions using the National Institute for Standards Technology (NIST) code and note that dissolved amounts of C3 and C4 compounds are likely to make Titan lakes much more viscous than pure ethane or methane, even without allowing for suspended particulates which would increase the viscosity further. Wind tunnel experiments show a strong dependence of capillary wave growth on liquid viscosity, and this effect may explain the apparent absence so far of waves, contrary to prior expectations that generation of gravity waves by wind should be easy on Titan. On the other hand, we note that winds over Titan lakes predicted with the TitanWRF Global Circulation Model indicate radar observations so far have in any case been when winds have been low (0.5-0.7 m/s), possibly below the wave generation threshold, while peak winds during summer may reach 1-2 m/s. Thus observations of Titan's northern lakes during the coming years by the Cassini Solstice mission offer the highest probability of observing wind-roughening of lake surfaces, while observations of Ontario Lacus in the south will likely continue to show it to be flat and smooth.

Lorenz, Ralph D.; Newman, Claire; Lunine, Jonathan I.

2010-06-01

186

J. Great Lakes Res. 28(3):451465 Internat. Assoc. Great Lakes Res., 2002  

E-print Network

J. Great Lakes Res. 28(3):451­465 Internat. Assoc. Great Lakes Res., 2002 Secular Changes in Great Lakes Water Level Seasonal Cycles Frank H. Quinn Great Lakes Environmental Research Laboratory National. The three primary scales of Great Lakes water level fluctuations are interannual, sea- sonal, and episodic

187

Lake-level frequency analysis for Devils Lake, North Dakota  

USGS Publications Warehouse

An annual lake-volume model and a statistical water mass-balance model were used to estimate future lake-level probabilities for Devils Lake. Comparison of the models indicates upper exceedance levels of the water mass-balance model increase much more rapidly than those of the annual lake-volume model. For simulation year 5, the 99-percent exceedance is 1,417.6 feet above sea level for the annual lake-volume model and 1,423.2 feet above sea level for the water mass-balance model.

Wiche, Gregg J.; Vecchia, Aldo V.

1996-01-01

188

Connecting the Final Drainage of Lake Agassiz to the 8.2 ka Event by Means of a High- Resolution Sea-Level Record From the Mississippi Delta  

NASA Astrophysics Data System (ADS)

The catastrophic drainage of proglacial lakes Agassiz and Ojibway (LAO) in the early Holocene is widely believed to have triggered the 8.2 ka cold event. The timing of the LAO drainage, however, remains poorly constrained, which impedes our understanding of the abruptness of this climate change in response to a rapid freshwater forcing. Dating of the LAO drainage in the Hudson Bay area (Barber et al., 1999) yielded an age of 8.47 0.30 ka, thus leaving large uncertainties about its connection with the 8.2 ka event. Here we refine the chronology of the final LAO drainage by constructing a high-resolution sea-level record from the Mississippi Delta with the basal peat approach. Two separate basal peat beds are interpreted to bracket an abrupt sea-level rise around 8.2 ka. The stratigraphically deeper level (Level A) contains a 2 cm basal peat layer that is abruptly overlain by Rangia cuneata- bearing lagoonal muds, representing the onset of an abrupt sea-level rise. The stratigraphically shallower level (Level B) contains a 6 cm basal peat layer that is covered by organic-rich muds, representing the end of the abrupt sea-level rise. Radiocarbon dating of different fractions of macrofossils from each peat layer yields consistent ages. The peat layer from Level A and the base of the peat layer from Level B yield ages of 8257 Cal. yr BP (median age with 2 sigma range of 8198-8270) and 8258 Cal. yr BP (median age with 2 sigma range of 8198-8270), respectively. The indistinguishable ages from these two peat layers, together with the diagnostic stratigraphic features, confirms that sea-level rise was likely instantaneous. This new chronology of the final LAO drainage is similar to the timings of the onset of the 8.2 ka event determined from high-resolution studies of Greenland ice cores and an Omani stalagmite, suggesting an instantaneous ocean-atmospheric system response to freshwater forcing, consistent with model predictions.

Li, Y.; Tornqvist, T. E.; Nevitt, J. M.; Shen, Z.; Yu, S.

2008-12-01

189

THE STATE OF SEA GRANT 2010  

E-print Network

Lakeshore, Lake Michigan (Michigan Sea Grant); A Taku Fisheries processing plant worker shows off a nice by the National Sea Grant Advisory Board, November 2010 National Sea Grant College Program Biennial Report

190

Deep-Sea Technology  

NSDL National Science Digital Library

In this lesson plan students will learn about special vehicles used in recent Black Sea research and the theory that the Black Sea during the Ice Age was an isolated freshwater lake surrounded by farmland that was eventually flooded. Students will describe the purpose of the research vehicles by writing newspaper articles pretending they have just returned from the Black Sea expedition.

191

Genome sequence of Haloplasma contractile, an unusual contractile bacterium from a deep-sea anoxic brine lake.  

PubMed

We present the draft genome of Haloplasma contractile, isolated from a deep-sea brine and representing a new order between Firmicutes and Mollicutes. Its complex morphology with contractile protrusions might be strongly influenced by the presence of seven MreB/Mbl homologs, which appears to be the highest copy number ever reported. PMID:21705599

Antunes, Andr; Alam, Intikhab; El Dorry, Hamza; Siam, Rania; Robertson, Anthony; Bajic, Vladimir B; Stingl, Ulrich

2011-09-01

192

Genome Sequence of Halorhabdus tiamatea, the First Archaeon Isolated from a Deep-Sea Anoxic Brine Lake?  

PubMed Central

We present the draft genome of Halorhabdus tiamatea, the first member of the Archaeaever isolated from a deep-sea anoxic brine. Genome comparison with Halorhabdus utahensisrevealed some striking differences, including a marked increase in genes associated with transmembrane transport and putative genes for a trehalose synthase and a lactate dehydrogenase. PMID:21705593

Antunes, Andre; Alam, Intikhab; Bajic, Vladimir B.; Stingl, Ulrich

2011-01-01

193

Genome Sequence of Haloplasma contractile, an Unusual Contractile Bacterium from a Deep-Sea Anoxic Brine Lake?  

PubMed Central

We present the draft genome of Haloplasma contractile, isolated from a deep-sea brine and representing a new order between Firmicutesand Mollicutes. Its complex morphology with contractile protrusions might be strongly influenced by the presence of seven MreB/Mbl homologs, which appears to be the highest copy number ever reported. PMID:21705599

Antunes, Andre; Alam, Intikhab; El Dorry, Hamza; Siam, Rania; Robertson, Anthony; Bajic, Vladimir B.; Stingl, Ulrich

2011-01-01

194

Genome sequence of Halorhabdus tiamatea, the first archaeon isolated from a deep-sea anoxic brine lake.  

PubMed

We present the draft genome of Halorhabdus tiamatea, the first member of the Archaea ever isolated from a deep-sea anoxic brine. Genome comparison with Halorhabdus utahensis revealed some striking differences, including a marked increase in genes associated with transmembrane transport and putative genes for a trehalose synthase and a lactate dehydrogenase. PMID:21705593

Antunes, Andr; Alam, Intikhab; Bajic, Vladimir B; Stingl, Ulrich

2011-09-01

195

Lake Effect Clouds  

NASA Technical Reports Server (NTRS)

The lake effect is particularly clear in this Sea-viewing Wide field-of-view Sensor (SeaWiFS) true-color image of the North American Great Lakes region, acquired December 5, 2000. Lakes Nipigon, Superior, and Michigan show striking contrasts between clear and cloudy air as the wind blows from the northwest across the lakes. As it flows across the relatively warm lakes, the cold dry air gathers heat and moisture from the surface. The warm moist air rises into the atmosphere and mixes vigorously with the cold dry air above. The layer of warm moist air deepens as it travels across the lake. Some of the evaporated water from the lake condenses into streamers of fog rising from the surface, while much of the moisture condenses to form a stratocumulus cloud in the upper half of the mixed layer. The cloud-forming water droplets may freeze into ice crystals and, due to accumulated water deposition over time, grow into snowflakes. This process can generate snowstorms that produce significant amounts of snowfall downwind. It is not uncommon for lake effect snowstorms to produce as much as two feet of snow within a 24-hour period in northwestern parts of New York and Pennsylvania. Image provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

2002-01-01

196

Developing Great Lakes Ice Model (GLIM) using CIOM (Coupled Ice-Ocean Model) in Lake Erie  

E-print Network

sea ice coverage with model results for winter 2004. #12;Figure 2: Seasonal cycle of ice thickness dynamics in the Great Lakes. This is in part because sea ice dynamics and thermodynamics control the waterDeveloping Great Lakes Ice Model (GLIM) using CIOM (Coupled Ice- Ocean Model) in Lake Erie Primary

197

Reproductive isolation, evolutionary distinctiveness and setting conservation priorities: The case of European lake whitefish and the endangered North Sea houting (Coregonus spp.)  

PubMed Central

Background Adaptive radiation within fishes of the Coregonus lavaretus complex has created numerous morphs, posing significant challenges for taxonomy and conservation priorities. The highly endangered North Sea houting (C. oxyrhynchus; abbreviated NSH) has been considered a separate species from European lake whitefish (C. lavaretus; abbreviated ELW) due to morphological divergence and adaptation to oceanic salinities. However, its evolutionary and taxonomic status is controversial. We analysed microsatellite DNA polymorphism in nine populations from the Jutland Peninsula and the Baltic Sea, representing NSH (three populations, two of which are reintroduced) and ELW (six populations). The objectives were to: 1) analyse postglacial recolonization of whitefish in the region; 2) assess the evolutionary distinctiveness of NSH, and 3) apply several approaches for defining conservation units towards setting conservation priorities for NSH. Results Bayesian cluster analyses of genetic differentiation identified four major groups, corresponding to NSH and three groups of ELW (Western Jutland, Central Jutland, Baltic Sea). Estimates of historical migration rates indicated recolonization in a north-eastern direction, suggesting that all except the Baltic Sea population predominantly represent postglacial recolonization via the ancient Elbe River. Contemporary gene flow has not occurred between NSH and ELW, with a divergence time within the last 4,000 years suggested from coalescence methods. NSH showed interbreeding with ELW when brought into contact by stocking. Thus, reproductive isolation of NSH was not absolute, although possible interbreeding beyond the F1 level could not be resolved. Conclusion Fishes of the C. lavaretus complex in the Jutland Peninsula originate from the same recolonization event. NSH has evolved recently and its species status may be questioned due to incomplete reproductive isolation from ELW, but it was shown to merit consideration as an independent conservation unit. Yet, application of several approaches for defining conservation units generated mixed outcomes regarding its conservation priority. Within the total species complex, it remains one among many recently evolved unique forms. Its uniqueness and high conservation priority is more evident at a local geographical scale, where conservation efforts will also benefit populations of a number of other endangered species. PMID:18471278

2008-01-01

198

Taconic foreland basin evolution: Sedimentology and cement stratigraphy of the Black River Group limestones in the Champlain Basin  

SciTech Connect

The Black River Group (Middle Ordovician, Mohawkian Series) limestones in the Champlain Basin record the transition between the shallow deposits of the underlying Chazy Group limestones and the shale-limestone couplets of the overlying Trenton Group which record rapid deepening of the foreland basin. The Black River Group was deposited in a subsiding foreland basin during the early stages of the Taconic Orogeny. Syn-depositional block faulting as a result of thrust loading has been demonstrated to affect Chazy and Trenton Group deposition. Abrupt lithofacies changes within the Black River Group record the dynamic bathymetry present in the Champlain Basin during its deposition. The Black River Group helps refine the timing of extensional block faulting during the Taconic Orogeny. The Black River Group in the Champlain Basin is a relatively thin unit, approximately 80 feet thick at Crown Point, New York. Exposures between Crown Point, NY and South Hero Island, VT record deposition of the Black River Group limestones in a protected lagoonal environment, with an evolving fringing pellet shoal barrier complex. Eight lithofacies are defined, grading from a basal sandstone and/or a sandy dolomite, to a micrite to biomicrite, to an intra-pelsparite of a shoal environment. Intraclast horizons and broken, rounded marine allochems suggest the influence of storm activity as a modifier of depositional history. Rapid deepenings into the normal marine subtidal environment, as well as micro-karst textures and fossil beach rock exposures are interpreted to represent sudden bas level changes, possibly from syndepositional block fault movement. Although dynamic bathymetry influences the stratigraphy within the Black River Group, a macro-scale deepening upwards on a formation scale is present, representing subsidence of the foreland basin.

Bechtel, S.C.; Mehrtens, C.J. (Univ. of Vermont, Burlington, VT (United States). Geology Dept.)

1993-03-01

199

33 CFR 100.120 - Special Local Regulations; Marine Events Held in the Coast Guard Sector Northern New England...  

...regulated area includes all waters of Lake Champlain in the vicinity of Saint Albans...all waters of Cumberland Bay on Lake Champlain in the vicinity of Plattsburgh...Paddling Boat Race. Sponsor: Lake Champlain Maritime Museum. ...

2014-07-01

200

Whiting in Lake Michigan  

NASA Technical Reports Server (NTRS)

Satellites provide a view from space of changes on the Earth's surface. This series of images from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) aboard the Orbview-2 satellite shows the dramatic change in the color of Lake Michigan during the summer. The bright color that appears in late summer is probably caused by calcium carbonate-chalk-in the water. Lake Michigan always has a lot of calcium carbonate in it because the floor of the lake is limestone. During most of the year the calcium carbonate remains dissolved in the cold water, but at the end of summer the lake warms up, lowering the solubility of calcium carbonate. As a result, the calcium carbonate precipitates out of the water, forming clouds of very small solid particles that appear as bright swirls from above. The phenomenon is appropriately called a whiting event. A similar event occured in 1999, but appears to have started later and subsided earlier. It is also possible that a bloom of the algae Microcystis is responsible for the color change, but unlikely because of Lake Michigan's depth and size. Microcystis blooms have occured in other lakes in the region, however. On the shore of the lake it is possible to see the cities of Chicago, Illinois, and Milwaukee, Wisconsin. Both appear as clusters of gray-brown pixels. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

2002-01-01

201

Assessment of trace element levels in muscle tissues of fish species collected from a river, stream, lake, and sea in Sakarya, Turkey.  

PubMed

Levels of some trace and essential elements, including Al, B, Ba, Cr, Cu, Fe, Mn, Ni, Sr, and Zn, were determined in 17 different fish species from Sakarya River, ark Stream, Sapanca Lake, and Western Black Sea using ICP-OES after microwave (MW) digestion procedure. During preparation of samples for analysis, wet and MW digestion methods were also compared. Accuracy of the digestion methods was checked by the analysis of DORM-3 reference material (Fish Protein Certified Reference Material for Trace Metals). Concentrations of trace elements were found as Al: 6.5-48.5, B: 0.06-3.30, Ba: 0.09-2.92, Cr: 0.02-1.64, Cu: 0.13-2.28, Fe: 7.28-39.9, Mn: 0.08-11.4, Ni: 0.01-26.1, Sr: 0.17-13.5, and Zn: 11.5-52.9?g?g(-1). The obtained results were compared with other studies published in the literature. Trace element levels in various fish species collected from waters in Sakarya region were found to be below limit values provided by Turkish Food Codex (TFC), Food and Agriculture Organization (FAO), and World Health Organization (WHO). PMID:24790570

Kpeli, Tlay; Altunda?, Hseyin; Imamo?lu, Mustafa

2014-01-01

202

Assessment of Trace Element Levels in Muscle Tissues of Fish Species Collected from a River, Stream, Lake, and Sea in Sakarya, Turkey  

PubMed Central

Levels of some trace and essential elements, including Al, B, Ba, Cr, Cu, Fe, Mn, Ni, Sr, and Zn, were determined in 17 different fish species from Sakarya River, ark Stream, Sapanca Lake, and Western Black Sea using ICP-OES after microwave (MW) digestion procedure. During preparation of samples for analysis, wet and MW digestion methods were also compared. Accuracy of the digestion methods was checked by the analysis of DORM-3 reference material (Fish Protein Certified Reference Material for Trace Metals). Concentrations of trace elements were found as Al: 6.548.5, B: 0.063.30, Ba: 0.092.92, Cr: 0.021.64, Cu: 0.132.28, Fe: 7.2839.9, Mn: 0.0811.4, Ni: 0.0126.1, Sr: 0.1713.5, and Zn: 11.552.9?g?g?1. The obtained results were compared with other studies published in the literature. Trace element levels in various fish species collected from waters in Sakarya region were found to be below limit values provided by Turkish Food Codex (TFC), Food and Agriculture Organization (FAO), and World Health Organization (WHO). PMID:24790570

Kupeli, Tulay; Altundag, Huseyin; Imamoglu, Mustafa

2014-01-01

203

Archaeal and bacterial communities respond differently to environmental gradients in anoxic sediments of a California hypersaline lake, the Salton Sea.  

PubMed

Sulfidic, anoxic sediments of the moderately hypersaline Salton Sea contain gradients in salinity and carbon that potentially structure the sedimentary microbial community. We investigated the abundance, community structure, and diversity of Bacteria and Archaea along these gradients to further distinguish the ecologies of these domains outside their established physiological range. Quantitative PCR was used to enumerate 16S rRNA gene abundances of Bacteria, Archaea, and Crenarchaeota. Community structure and diversity were evaluated by terminal restriction fragment length polymorphism (T-RFLP), quantitative analysis of gene (16S rRNA) frequencies of dominant microorganisms, and cloning and sequencing of 16S rRNA. Archaea were numerically dominant at all depths and exhibited a lesser response to environmental gradients than that of Bacteria. The relative abundance of Crenarchaeota was low (0.4 to 22%) at all depths but increased with decreased carbon content and increased salinity. Salinity structured the bacterial community but exerted no significant control on archaeal community structure, which was weakly correlated with total carbon. Partial sequencing of archaeal 16S rRNA genes retrieved from three sediment depths revealed diverse communities of Euryarchaeota and Crenarchaeota, many of which were affiliated with groups previously described from marine sediments. The abundance of these groups across all depths suggests that many putative marine archaeal groups can tolerate elevated salinity (5.0 to 11.8% [wt/vol]) and persist under the anaerobic conditions present in Salton Sea sediments. The differential response of archaeal and bacterial communities to salinity and carbon patterns is consistent with the hypothesis that adaptations to energy stress and availability distinguish the ecologies of these domains. PMID:19948847

Swan, Brandon K; Ehrhardt, Christopher J; Reifel, Kristen M; Moreno, Lilliana I; Valentine, David L

2010-02-01

204

Head capsule deformities in midge larvae exposed to Burlington Harbor (Lake Champlain) sediments -- field and laboratory investigations  

SciTech Connect

Investigations of sediment associated contaminants in Burlington Harbor indicated the harbor contains elevated levels of a number of pollutants. Lead, silver, mercury and total PAH levels exceed NOAA`s ER-M at numerous sites in the harbor. Benzo(a)pyrene concentrations (ranging from 0.055 to 6.64 ug/g (dry wt.)) exceed the ER-M at a number of sites. Pyrene, phenanthrene, fluoranthene, chrysene, anthracene and fluorene also exceed the ER-M at a number of stations within the harbor. Despite these relatively high levels of contaminants found in harbor sediments, solid phase and pore water exposures with Ceriodaphnia dubia indicate acute toxicity at only a limited number of sites. Examination of midge larvae populations from the harbor, however, indicates a high rate of head capsule deformities at some sites. Preliminary work which exposed laboratory cultures of Chironomus tentans to harbor sediment induced a 17% incidence in deformities in the F{sub 1} generation, a 50% incidence in the F{sub 2} generation and a 75% in the F{sub 3} generation. The incidence of deformities decreased substantially when F{sub 3} generation organisms were reared in clean substrate. Laboratory cultures of C. tentans are being exposed to sediments from various harbor sites for determination of head capsule deformity induction. In addition, several generations of larvae will be reared in sediment to determine the overall impacts on survival and whether deformities increase in subsequent generations.

Lester, D.; Williams, A.; McIntosh, A.; Lacey, R. [Univ. of Vermont, Burlington, VT (United States). School of Natural Resources

1994-12-31

205

INVESTIGATIONS INTO THE CAUSES OF AMPHIBIAN MALFORMATIONS IN THE LAKE CHAMPLAIN BASIN OF NEW ENGLAND (AWARDED PROJECT)  

EPA Science Inventory

The concurrent geographic extent and rate of amphibian malformations appear to have markedly increased above background levels in recent years in many states and Canadian provinces as documented by the North American Reporting Center for Amphibian Malformations (www.npwrc.usgs.go...

206

Earthwatch Radio: Sea Lamprey Resurgence  

NSDL National Science Digital Library

This radio broadcast describes efforts to control the population of sea lampreys in the Great Lakes. Sea lampreys, an invasive species from the Atlantic Ocean, have populated the lakes for years, but have recently increased in numbers despite efforts to control them. A hole in a dam on the Manistique River on the northern edge of Lake Michigan is thought to have caused the problem. The clip is 2 minutes in length and may be downloaded in MP3 format.

Kalinowski, Laura

2012-09-17

207

3D visualization of derived hydrophysical parameters in Lakes and Inland Seas. New approach to applied hydrodynamics.  

NASA Astrophysics Data System (ADS)

Based on numerical simulation results, derived parameters computed from output variables and represented in 3D are used to have a clearer approach to the hydrodynamics of real systems. More precisely, a 3D dynamic visualization of the Shannon entropy of the velocity direction field is shown to illustrate the horizontal mixing related to the flow dynamics in the case of the Aral and Black sea applications. Previous to that some video test cases are presented in order to have a close view of what is highlighted with this approach. Complementarily, the physical meaning of the Shannon entropy of velocity directions is discussed in comparison with more standard derived variables such as the Obuko-Weiss parameter. The Shannon entropy of other scalar fields is also represented and used for the discussion. The utility of these tools for science as well as for management and more popular applications is discussed. Acknowledgments: This research was developed within the framework of the CLIMSEAS project FP7-IRSES-2009 (ref. 247512).

Barcaru, A.; Roget, E.; Sbert, M.; Zavialov, P.; Korontenko, K.; Feixas, M.

2012-04-01

208

Antibiotic producing microorganisms from River Wiwi, Lake Bosomtwe and the Gulf of Guinea at Doakor Sea Beach, Ghana  

PubMed Central

Background Microorganisms have provided a wealth of metabolites with interesting activities such as antimicrobial, antiviral and anticancer. In this study, a total of 119 aquatic microbial isolates from 30 samples (taken from water bodies in Ghana) were screened by the agar-well diffusion method for ability to produce antibacterial-metabolites. Results Antibacterial activity was exhibited by 27 of the isolates (14 bacteria, 9 actinomycetes and 4 fungi) against at least one of the indicator microorganisms: Enterococcus faecalis (ATCC 29212), Bacillus thuringiensis (ATCC 13838), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Proteus vulgaris (NCTC 4635) and Bacillus Subtilis (NCTC 10073). A sea isolate MAI2 (identified as a strain of Pseudomonas aeruginosa) exhibited the highest antibacterial activity (lowest zone of inhibition?=?22 mm). The metabolites of MAI2 extracted with chloroform were stable to heat and gave minimum inhibitory concentrations ranging between 250 and 2000 ?g/ml. Bioautography of the extract revealed seven active components. Conclusion This study has therefore uncovered the potential of water bodies in the West African sub-region as reservoirs of potent bioactive metabolite producing microorganisms. PMID:23072432

2012-01-01

209

Recruitment Dynamics of the 19711991 Year-Classes of Lake Trout in Michigan Waters of Lake Superior  

Microsoft Academic Search

In the 1950s, populations of lake trout Salvelinus namaycush in Lake Superior collapsed because of excessive exploitation and predation by sea lampreys Petromyzon marinus. Restoration began in the 1950s with the stocking of juvenile, hatchery-reared lake trout and controls on fisheries and sea lampreys. Partial restoration was declared in 1996 because wild fish made up most of the populations in

Jessica M. Richards; Michael J. Hansen; Charles R. Bronte; Shawn P. Sitar

2004-01-01

210

Late Glacial to Holocene benthic foraminifera in the Marmara Sea: implications for Black Sea^Mediterranean Sea  

E-print Network

a low-lying low salinity `Black Sea Lake' at V7.15 ka (popularly known as the `Noah's Flood Hypothesis and persistent stratification of the water column in the Marmara Sea throughout the Holocene is entirely

Kaminski, Michael A.

211

East Siberian Sea, Russia  

NASA Technical Reports Server (NTRS)

The winter sea ice in the east Siberian Sea is looking a bit like a cracked windshield in these true-color Moderate Resolution Imaging Spectroradiometer (MODIS) images from June 16 and 23, 2002. North of the thawing tundra, the sea ice takes on its cracked, bright blue appearance as it thins, which allows the reflection of the water to show through. Numerous still-frozen lakes dot the tundra. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

2002-01-01

212

Lateglacial of Lake Onega Contribution to the history of the eastern Baltic basin  

Microsoft Academic Search

New stratigraphy data especially diatom analyses are presented from the area north of Lake Onega relevant to the discussion on possible Lateglacial connection between the Baltic Sea and White Sea. Following the deglaciation 12,00011,000 years ago Lake Onega basin was occupied by a system of ice dammed lakes which drained to the Lake Ladoga basin. When the ice retreated from

Matti Saarnisto; Tuulikki Grnlund; Ilpo Ekman

1995-01-01

213

Second Lake Lake William  

E-print Network

Lake M arshallBro ok Sackville River Willis L. Juniper L. Black L. Barrett L. Fenerty Lake Horse Shoe S H R M F F Downsview Mall F Windsor Junction Lower Sackville Burnside Industrial Park Cobequid Multi. NictauxDr Newcombe Dr Neily Dr. Lennox Dr. Lu m sden Cres Lynnville Dr. Beaverbank - Windsor Junction Road

Beaumont, Christopher

214

Highlights of large lake research and management in Europe  

Microsoft Academic Search

Lakes in Europe have a bipolar distribution by latitude with higher lake densities in the north (5865 N) and south (3848\\u000a N). By area, 95% of the large lakes (>100km2) are located at altitudes lower than 100m above sea level (ASL) and only 1% lie higher than 1,000m ASL. Physically large\\u000a lakes exhibit several similarities to seas and oceans in

Peeter Nges; Klli Kangur; Tiina Nges; Anu Reinart; Heikki Simola; Markku Viljanen

2008-01-01

215

Highlights of large lake research and management in Europe  

Microsoft Academic Search

Lakes in Europe have a bipolar distribution by latitude with higher lake densities in the north (5865 N) and south (3848\\u000a N). By area, 95% of the large lakes (>100 km2) are located at altitudes lower than 100 m above sea level (ASL) and only 1% lie higher than 1,000 m ASL. Physically large\\u000a lakes exhibit several similarities to seas

Peeter Nges; Klli Kangur; Tiina Nges; Anu Reinart; Simola Heikki; Viljanen Markku

216

Quaternary Science Reviews 23 (2004) 13131332 Ice-dammed lakes and rerouting of the drainage of northern  

E-print Network

, e.g. toward the Caspian Sea, formed south of these ice sheets. Some lakes are reconstructed from, and that way to the Caspian Sea. Climate modelling shows that the lakes caused lower summer temperatures

Möller, Per

217

Deglaciation chronology, sea-level changes and environmental changes from Holocene lake sediments of Germania Havn S, Sabine , northeast Greenland  

NASA Astrophysics Data System (ADS)

Germania Havn S is located at the outermost coast of northeastern Greenland. According to radiocarbon dating, the lake basin was deglaciated in the early Holocene, around 11,000 cal yr BP. At that time the lake was a marine bay, but the lake was isolated soon after deglaciation at ~ 10,600 cal yr BP. The marine fauna was species-poor, indicating harsh conditions with a high sedimentation rate and lowered salinity due to glacial meltwater supply. The pioneer vegetation around the lake was dominated by mosses and herbs. Deposition of relatively coarse sediments during the early Holocene indicates erosion of the newly deglaciated terrain. Remains of the first woody plant (Salix herbacea) appear at 7600 cal yr BP and remains of other woody plants (Salix arctica, Dryas octopetala, Cassiope tetragona and Empetrum nigrum) appear around one millennium later. Declining concentrations of D. octopetala and the caddis fly Apatania zonella in the late Holocene probably imply falling summer temperatures. Only moderate changes in the granulometric and geochemical record during the Holocene indicate relatively stable environmental settings in the lake, which can probably be explained by its location at the outer coast and the buffering effect of the neighboring ocean.

Bennike, Ole; Wagner, Bernd

2012-07-01

218

Cornell University, Office of Sponsored Programs Awards Received in February 2004  

E-print Network

) ADOPTIVE PLACEMENTS FOR CHILDREN IN FOSTER CARE $43,761 GEA 40690 BAKER, DALE SEA GRANT EXT SUNY RF LAKE CHAMPLAIN SEA GRANT $66,802 KLH 41816 BAKER, DALE SEA GRANT EXT SUNY RF TIER-BASED MONITORING FOR TOXIC

Danforth, Bryan Nicholas

219

A r c t i c Barents Sea  

E-print Network

extent of sea ice (as of 1975) Lena Yukon Lena River Yenisey Lake Onega Volga North Sea East Siberian N o t h A t l a n t i c O c e a n Labrador Sea Norwegian Sea Kama Dnieper Sea Amur Alaska Gulf of Peace er

Martin, Jeff

220

Hydrology of Lake Butler, Orange County, Florida  

USGS Publications Warehouse

Lake Butler is one of the lakes that collectively make up the Butler chain of lakes in the headwaters of the Kissimmee River, Florida. The bottom configuration of the lake is typical of relict karst features formed during lower stages in sea level. The top of the Floridan aquifer is 50 to 100 feet below the land surface. The drainage area of Lake Butler is approximately 14.5 sq mi and is comprised of sub-basins of other lakes in the vicinity. Surface outflow from Lake Butler is generally southward to Cypress Creek, a tributary of the Kissimmee River. The extremes in lake stage for the period 1933-81 are 94.67 ft on June 23, 1981 and 101.78 ft on September 13, 1960. The median lake stage for this period was 99.28 ft above sea level. The quality of water in Lake Butler is excellent, based on studies of physical, chemical, and biological conditions by the Orange County Pollution Control Department. The lake water is slightly acidic and soft (48 mg/L hardness as calcium carbonate). Pesticides in water were below detection levels at two sites sampled in the lake, but were detected in the bottom sediments. (USGS)

Smoot, James L.; Schiffer, Donna M.

1984-01-01

221

Biogeochemical phosphorus mass balance for Lake Baikal, southeastern Siberia, Russia  

USGS Publications Warehouse

Extensive data for Lake Baikal have been synthesized into a geochemical mass balance for phosphorus (P). Some of the P budget and internal cycling terms for Baikal have been compared to similar terms for oligotrophic Lake Superior, mesotrophic Lake Michigan and the Baltic Sea, and the Ocean. Lake Baikal has a large external source of fluvial P compared to the Laurentian upper Great Lakes and the Ocean. The major tributary to Lake Baikal has experienced substantial increases in organic P loading during the past 25 years. This, coupled with potential P inputs from possible phosphorite mining, may threaten Baikal's oligotrophic status in the future. Water-column remineralization of particulate organic P is substantially greater in Lake Baikal than in the Laurentian Great Lakes. This is probably due to the great water depths of Lake Baikal. There is a gradient in P burial efficiency, with very high values (80%) for Lake Baikal and Lake Superior, lower values (50%) for Lake Michigan and the Baltic Sea, and a low value (13%) for the Ocean. The accumulation rate of P in Lake Baikal sediments is somewhat greater than that in the Laurentian upper Great Lakes and the Baltic Sea, and much greater than in the Ocean. Benthic regeneration rates are surprisingly similar for large lacustrine and marine environments and supply less than 10% of the P utilized for primary production in these aquatic environments.

Callender, E.; Granina, L.

1997-01-01

222

Salton: A Sea of Controversy  

NSDL National Science Digital Library

The Salton Sea is an accidental lake that receives used irrigation water from the Colorado River. Humans have profoundly altered the area's ecosystems. The sea is important for wildlife and recreation but is now saltier than the ocean. How might it be sav

Vessey, Kristin B.

2000-09-01

223

In situ determination of the annual thermal habitat use by lake trout (Salvelinus namaycush) in Lake Huron  

USGS Publications Warehouse

Records of the temperatures occupied by 33 lake trout (Salvelinus namaycush) at large in Lake Huron were obtained for up to 14 months per fish, at 75-minute intervals, from surgically implanted archival temperature tags. The dataset covered nearly three years, from October 1998 to June 2001, and included 160,000 observations. The objectives of the tagging were to obtain temperature data to refine bioenergetics models of sea lamprey (Petromyzon marinus) predation on lake trout, and compare the temperatures occupied by strains of lake trout stocked in Lake Huron. The seasonal, thermal-use profiles of lake trout followed the general warming and cooling pattern of Lake Huron. During periods when the zone of surface water mixing extended below the depth range occupied by lake trout, variability among individual fish and strains was low and followed surface temperature. However, during the period of summer stratification, the average temperatures occupied varied substantially among individual fish and strains. Strains originating from the upper Great Lakes (Lake Superior and Lewis Lake, WY) occupied similar temperatures. Between June and mid August, upper Great Lakes lake trout typically occupied water several degrees warmer than that occupied by lake trout of Finger Lakes, New York origin. Most of the lake trout occupied summer temperatures lower than the preferred temperatures suggested by laboratory studies. In October, all strains occupied water as warm or warmer than that occupied in summer, which may partially explain the higher lethality of sea lamprey attacks during October.

Bergstedt, Roger A.; Argyle, Ray L.; Seelye, James G.; Scribner, Kim T.; Curtis, Gary L.

2003-01-01

224

Progress toward lake trout restoration in Lake Michigan  

USGS Publications Warehouse

Progress toward lake trout restoration in Lake Michigan is described through 1993. Extinction of the native lake trout fishery by sea lamprey predation, augmented by exploitation and habitat destruction, resulted in an extensive stocking program of hatchery-reared lake trout that began in 1965. Sea lamprey abundance was effectively controlled using selective chemical toxicants. The initial stocking produced a measurable wild year class of lake trout by 1976 in Grand Traverse Bay, but failed to continue probably due to excessive exploitation. The overall lack of successful reproduction lakewide by the late 1970s led to the development and implementation in 1985 of a focused interagency lakewide restoration plan by a technical committee created through the Lake Committee structure of the Great Lakes Fishery Commission. Strategies implemented in 1985 by the plan included setting a 40% total mortality goal lakewide, creating two large refuges designed to encompass historically the most productive spawning habitat and protect trout stocked over their home range, evaluating several lake trout strains, and setting stocking priorities throughout the lake. Target levels for stocking in the 1985 Plan have never been reached, and are much less than the estimated lakewide recruitment of yearlings by the native lake trout stocks. Since 1985, over 90% of the available lake trout have been stocked over the best spawning habitat, and colonization of the historically productive offshore reefs has occurred. Concentrations of spawning lake trout large enough for successful reproduction, based on observations of successful hatchery and wild stocks, have developed at specific reefs. Continued lack of recruitment at these specific sites suggests that something other than stock abundance has limited success. Poor survival of lake trout eggs, assumed to be related to contaminant burden, occurred in the late 1970s and early 1980s, but survival has since increased to equal survival in the hatchery. A recent increase in lamprey wounding rates in northern Lake Michigan appears to be related to the uncontrolled build-up of lampreys in the St. Marys River a tributary of Lake Huron. If left uncontrolled, further progress toward restoration in the Northern Refuge may be limited.

Holey, Mark E.; Rybicki, Ronald W.; Eck, Gary W.; Brown, Edward H., Jr.; Marsden, J. Ellen; Lavis, Dennis S.; Toneys, Michael L.; Trudeau, Tom N.; Horrall, Ross M.

1995-01-01

225

Dynamics of the Lake Michigan food web, 1970?2000  

Microsoft Academic Search

Herein, we document changes in the Lake Michigan food web between 1970 and 2000 and identify the fac- tors responsible for these changes. Control of sea lamprey (Petromyzon marinus) and alewife (Alosa pseudoharengus) populations in Lake Michigan, beginning in the 1950s and 1960s, had profound effects on the food web. Recoveries of lake whitefish (Coregonus clupeaformis) and burbot (Lota lota)

Charles P. Madenjian; Gary L. Fahnenstiel; Thomas H. Johengen; Thomas F. Nalepa; Henry A. Vanderploeg; Guy W. Fleischer; Philip J. Schneeberger; Darren M. Benjamin; Emily B. Smith; James R. Bence; Edward S. Rutherford; Dennis S. Lavis; Dale M. Robertson; David J. Jude; Mark P. Ebener

2002-01-01

226

Thermal structure and circulation in the great lakes  

Microsoft Academic Search

Large enough to include many oceanic phenomena, the Laurentian Great Lakes are more accurately described as inland seas. With the exception of the shallow Western Basin of Lake Erie, the lakes are thermally stratified in summer, homogeneous in winter, with average temperatures passing through the temperature of maximum density of fresh water (4C) in both the spring and the fall.

F. M. Boyce; M. A. Donelan; P. F. Hamblin; C. R. Murthy; T. J. Simons

1989-01-01

227

Aral Sea Evaporation (WMS)  

NSDL National Science Digital Library

The Aral Sea is actually not a sea at all, but an immense fresh water lake. In the last thirty years, more than sixty percent of the lake has disappeared because much of the river flow feeding the lake was diverted to irrigate cotton fields and rice paddies. Concentrations of salts and minerals began to rise in the shrinking body of water, leading to staggering alterations in the lakes ecology and precipitous drops in the Arals fish population. Powerful winds that blow across this part of Asia routinely pick up and deposit the now exposed lake bed soil. This has contributed to a significant reduction in breathable air quality, and crop yields have been appreciably affected due to heavily salt laden particles falling on arable land. This series of Landsat images taken in 1973, 1987 and 2000 show the profound reduction in overall area at the north end of the Aral, and a commensurate increase in land area as the floor of the sea now lies exposed.

Thomson, Joycelyn; Mitchell, Horace; Williams, Darrel

2005-02-15

228

Assessment of water and bottom sediment conditions in the bights of Kozmina and Lake Vtoroe (Nakhodka Gulf, Peter the Great Bay, the Sea of Japan)  

Microsoft Academic Search

The state of the water area in the Bays of Kozmina and Lake Vtoroe (Nakhodka Gulf is evaluated. The data given include water\\u000a temperature and salinity, biochemical oxygen demand, pH, alkalinity, chlorophyll a, organic matter, biogenic elements, oil\\u000a products, detergents, polycyclic aromatic hydrocarbons, phenols, and organochlorine pesticides in water and bottom sediments.\\u000a Pollutants may enter the system of bights from

N. I. Grigoreva; D. L. Pitruk

2011-01-01

229

Use of Sediment Quality Guidelines and pollution indicators for the assessment of heavy metal and PAH contamination in Greek surficial sea and lake sediments.  

PubMed

Eight different surface sediment samples (K1-K8) were collected from two separate areas of Lake Koumoundourou and two samples (E1 and E2) from one area of Elefsis Bay, Athens, Greece. The level of pollution attributed to heavy metals was evaluated using several pollution indicators. Degree of Contamination, Modified Contamination Degree and Geoaccumulation Indexes were applied in order to determine and assess the anthropogenic contribution of the selected six elements (Cr, Ni, Cu, Zn, As and Pb). Moreover, the adverse effects of the sediments to aquatic organisms, from both heavy metals and polycyclic aromatic hydrocarbons (PAHs), were determined by using Sediment Quality Guidelines. The results indicated that Lake Koumoundourou is contaminated with heavy metals in a moderate degree and almost 50% of the sediments are associated with frequent observation of adverse effects, when it comes to Ni and occasional observation of adverse effects, when it comes to Cu, Zn and Pb. As far as PAHs are concerned, around 60% of the samples can be occasionally associated to toxic biological effects according to the effect-range classification for phenanthrene, benzo(a)anthracene, chrysene and pyrene. Finally, samples taken from the north side of the lake are more contaminated with PAHs than the ones taken from the east side probably due to the existence of the water barrier which acts as a reservoir of PAHs. PMID:22821321

Hahladakis, John; Smaragdaki, Eleftheria; Vasilaki, Georgia; Gidarakos, Evangelos

2013-03-01

230

The Aral Sea Disaster  

NASA Astrophysics Data System (ADS)

The Aral Sea is a huge terminal lake located among the deserts of Central Asia. Over the past 10 millennia, it has repeatedly filled and dried, owing both to natural and human forces. The most recent desiccation started in the early 1960s and owes overwhelmingly to the expansion of irrigation that has drained its two tributary rivers. Lake level has fallen 23 m, area shrunk 74%, volume decreased 90%, and salinity grew from 10 to more than 100g/l, causing negative ecological changes, including decimation of native fish species, initiation of dust/salt storms, degradation of deltaic biotic communities, and climate change around the former shoreline. The population residing around the lake has also been negatively impacted. There is little hope in the foreseeable future to fully restore the Aral Sea, but measures to preserve/rehabilitate parts of the water body and the deltas are feasible.

Micklin, Philip

2007-05-01

231

Lake Constance  

article title: Lake Constance, Europe View ... This Multi-angle Imaging SpectroRadiometer (MISR) image of Lake Constance covers an area measuring 355 kilometers x 287 kilometers, and ... (nadir) camera on August 14, 2000. The large lake near the left-hand side of the image is bordered by Switzerland, Germany, ...

2013-04-17

232

Lake Powell  

article title: Lake Powell View Larger Image ... format (14.42 mb) This true-color image over Lake Powell was acquired by Multi-angle Imaging SpectroRadiometer (MISR) in late March 2000. Lake Powell was formed with the construction of the Glen Canyon Dam in 1963, on ...

2014-05-15

233

CONNECTICUT LAKES  

EPA Science Inventory

This is a 1:24,000-scale datalayer of named lakes in Connecticut. It is a polygon Shapefile that includes all lakes that are named on the U.S. Geologicial Survey (USGS) 7 minute topographic quadrangle maps that cover the State of Connecticut, plus other officially named lakes i...

234

Lake Sarez, Tajikistan  

NASA Technical Reports Server (NTRS)

Lake Sarez (top), deep in the Pamir mountains of Tajikistan, was created 90 years ago when a strong earthquake triggered a massive landslide that, in turn, became a huge dam along the Murghob River, now called the Usoi Dam. The resulting lake is perched above surrounding drainages at an elevation greater than 3000m, and is part of the watershed that drains the towering Akademi Nauk Range (see the regional image, lower). The lake is 61 km long and as deep as 500 m, and holds an estimated 17 cubic km of water. The area experiences considerable seismic activity, and scientists fear that part of the right bank may slump into the lake, creating a huge wave that will top over and possibly breach the natural dam. Such a wave would create a catastrophic flood downstream along the Bartang, Panj and Amu Darya Rivers, perhaps reaching all the way to the Aral Sea. Currently, central Asian governments, as well as the World Bank and the UN are monitoring the dam closely, and have proposed gradually lowering the lake level as a preventive measure. More information about the lake is available at the following web sites: Lake Sarez Study group, UN Report, Reliefweb Digital photograph numbers ISS002-E-7771 and ISS002-E-7479 were taken in the spring of 2001 from Space Station Alpha and are provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

2002-01-01

235

NOAA Technical Memorandum GLERL-138 GREAT LAKES BEACH HEALTH RESEARCH NEEDS  

E-print Network

NOAA Technical Memorandum GLERL-138 GREAT LAKES BEACH HEALTH RESEARCH NEEDS: WORKSHOP SUMMARY Great Lakes Beach Association in cooperation with NOAA, Great Lakes Environmental Research Laboratory and the Michigan Sea Grant Program U.S. Environmental Protection Agency U.S. Geological Survey Great Lakes

236

EVOLUTION IN LAKE TAI ECOSYSTEMS AS A RESULT OF GLOBAL ENVIRONMENTAL CHANGES AND HUMAN ACTIVITIES  

EPA Science Inventory

Large lakes evolve continuously through interaction with the physical, chemical, and biological environments of the surrounding watershed and lakes. ecent evidence from Lake Tai shows global climate and sea level changes led to a major change in Lake Tai from brackish to a freshw...

237

This article was downloaded by: [J. Ellen Marsden] On: 23 January 2013, At: 13:04  

E-print Network

://www.tandfonline.com/loi/utaf20 Lake Whitefish Diet, Condition, and Energy Density in Lake Champlain and the Lower Four Great Density in Lake Champlain and the Lower Four Great Lakes following Dreissenid Invasions, Transactions, and Energy Density in Lake Champlain and the Lower Four Great Lakes following Dreissenid Invasions Seth J

Marsden, Ellen

238

Lake trout (Salvelinus namaycush) populations in Lake Superior and their restoration in 1959-1993  

USGS Publications Warehouse

Naturally-reproducing populations of lake trout (Salvelinus namaycush) have been re-established in most of Lake Superior, but have not been restored to 1929-1943 average abundance. Progress toward lake trout restoration in Lake Superior is described, management actions are reviewed, and the effectiveness of those actions is evaluated; especially stocking lake trout as a tool for building spawning stocks, and subsequently, populations of wild recruits. Widespread destruction of lake trout stocks in the 1950s due to an intense fishery and sea lamprey (Petromyzon marinus) predation resulted in lower overall phenotypic diversity than was previously present. Stocking of yearling lake trout, begun in the 1950s, produced high densities of spawners that reproduced wherever inshore spawning habitat was widespread. Sea lampreys were greatly reduced beginning in 1961, using selective chemical toxicants and barrier dams, but continue to exert substantial mortality. Fishery regulation was least effective in Wisconsin, where excessive gillnet effort caused high by catch of lake trout until 1991, and in eastern Michigan, where lake trout restoration was deferred in favor of a tribal fishery for lake whitefish (Coregonus clupeaformis) in 1985. Restoration of stocks was quicker in offshore areas where remnant wild lake trout survived and fishing intensity was low, and was slower in inshore areas where stocked lake trout reproduced successfully and fishing intensity was high. Inshore stocks of wild lake trout are currently about 61% of historic abundance in Michigan and 53% in Wisconsin. Direct comparison of modern and historic abundances of inshore lake trout stocks in Minnesota and Ontario is impossible due to lack of historic stock assessment data. Stocks in Minnesota are less abundant at present than in Michigan or Wisconsin, and stocks in Ontario are similar to those in Michigan. Further progress in stock recovery can only be achieved if sea lampreys are depressed and if fisheries are constrained further than at present.

Hansen, Michael J.; Peck, James W.; Schorfhaar, Richard G.; Selgeby, James H.; Schreiner, Donald R.; Schram, Stephen T.; Swanson, Bruce L.; MacCallum, Wayne R.; Burnham-Curtis, Mary K.; Curtis, Gary L.; Heinrich, John W.; Young, Robert J.

1995-01-01

239

Sea and Land Breezes METR 4433, Mesoscale Meteorology  

E-print Network

in this section came from ZMAG) Definitions: The sea breeze is a local, thermally direct circulation arising from of water (ocean, large lakes) toward land and is caused by hydrostatic pressure gradient forces related. The leading edge of the sea breeze is called the sea breeze front. The basic structure of the sea breeze

Droegemeier, Kelvin K.

240

Hydrologic considerations in dewatering and refilling Lake Carlton : Orange and Lake Counties, Florida  

USGS Publications Warehouse

Lake Carlton straddles the line between Lake and Orange Counties in central Florida. The 382-acre lake is highly eutrophic and subject to virtually perpetual algal blooms. The Florida Game and Fresh Water Fish Commission has proposed to restore the lake to a less eutrophic state by dewatering the lake long enough to allow the muck on its bottom to dry and compact. Lake Carlton would be permanently sealed off from Lake Carlton. On the assumption that the seasonal rainfall would be normal, and that the dewatering phase would begin on March 1, the predicted time required to dewater the lake at a pumping rate of 50,000 gpm (gallons per minute) is 21 days. The average rate of pumping required to maintain the lake in a dewatered condition is computed to be 2,400 gpm. If pumping is ended May 31, the predicted altitude to which the lake would recover by October 31 as a result of net natural input is 56.2 feet above sea level. Raising the lake level to 63 feet above sea level by October 31 would require that the net natural input be supplemented at an average rate of about 4,860 gpm between May 31 and October 31. (Woodard-USGS)

Anderson, Warren; Hughes, G. H.

1977-01-01

241

Abundance Indices for Determining the Status of Lake Trout Restoration in Michigan Waters of Lake Superior  

Microsoft Academic Search

Self-sustaining populations of lake trout Sal vet in us namaycush have returned to most areas in Lake Superior, but progress toward achieving historic commercial yields has been difficult to measure because of unrecorded losses to predation by sea lamprey Petromyzon marinus and to fisheries. Consequently, we developed restoration targets (catch per effort, CPE; geometric mean number per kilometer of 114-mm

MICHAEL J. HANSEN; RICHARD G. SCHORFHAAR; JAMES W. PECK; JAMES H. SELGEBY; WILLIAM W. TAYLOR

1995-01-01

242

Performance of Two Strains of Lake Trout Stocked in the Midlake Refuge of Lake Michigan  

Microsoft Academic Search

To evaluate the performance of Seneca and Marquette strains of lake trout Salvelinus namaycush for restoring stocks in southern Lake Michigan, we compared relative abundance (fish per lift of 305 m of gill net), survival (slope of the decline in natural logarithms of relative abundance), growth (von Bertalanffy growth curves), and wounding rates by sea lamprey Petromyzon marinus of the

Patrick C. McKee; Michael L. Toneys; Michael J. Hansen; Mark E. Holey

2004-01-01

243

Gravity field over the Sea of Galilee: Evidence for a composite basin along a transform fault  

Microsoft Academic Search

The Sea of Galilee (Lake Kinneret) is located at the northern portion of the Kinneret-Bet Shean basin, in the northern Dead Sea transform. Three hundred kilometers of continuous marine gravity data were collected in the lake and integrated with land gravity data to a distance of more than 20 km around the lake. Analyses of the gravity data resulted in

Zvi Ben-Avraham; Uri ten Brink; Robin Bell; Margaret Reznikov

1996-01-01

244

SEA TURTLES Sea Turtles  

E-print Network

the loggerhead, Kemp's ridley, olive ridley, green, leatherback, and hawks- bill turtles. In the Pacific Ocean317 SEA TURTLES UNIT 24 Sea Turtles Unit 24 PROTECTED RESOURCES STAFF NMFS Office of Protected Center La Jolla, CA INTRODUCTION Sea turtles are highly migratory and widely distributed throughout

245

Beaufort Sea! Chukchi Sea!  

E-print Network

Beaufort Sea! Chukchi Sea! Herald Shoal Hanna Shoal Barrow Canyon Herald Canyon Bering Strait of the Alaska Coastal Current (a) Bering Strait! (b) Central Shelf! (c) BCH! (d) BCC/DBO! (e) BCM! BCC avg the Arctic Ocean through Bering Strait is transported across the shallow and expansive Chukchi Sea through

Pickart, Robert S.

246

Modeling Lake Erie ice dynamics: Process studies , Haoguo Hu2  

E-print Network

modeling in Lake Erie (Wake and Rumer, 1979, 1983) based on Hibler's (1979) dynamic-thermodynamic sea-ice efforts in coupled ice-ocean modeling in many subpolar seas and bays, such as in Hudson Bay (Wang et al with a viscous-plastic sea ice constitutive law (Hibler, 1979) and a multi-category ice thickness distribution

247

Evidence for Mesozoic Reactivation of Faults in the Northern Appalachians: K/Ar Dating of Fault Gouge from the Champlain Thrust, Vermont  

NASA Astrophysics Data System (ADS)

The Champlain Thrust of Northern Vermont marks a major decollement for the Middle to Late Ordovician Taconian Orogeny. At Lone Rock Point, Vermont, the fault places the Cambrian Dunham Dolomite over the Ordovician Iberville Shale. Previous work has shown that subsequent reactivation of the fault may have occurred during shortening associated with the Devonian Acadian Orogeny. New K/Ar dates on fault gouge sampled from the Lone Rock Point locality yield a surprisingly young Late Jurassic date (153 4 Ma) on a fine (<0.15 um) size fraction. Two intermediate fractions (0.5-0.2 um and 0.2-0.15 um) give Permian (270 4 Ma) and Triassic (223 4 Ma) dates, respectively, and a course (1.0-0.5 um) fraction gives a Carboniferous date (325 5 Ma). These course samples likely contain increasing proportions of detrital illite, and yet all size fractions provide dates that are significantly younger the depositional age of the surrounding rock. X-ray diffraction analysis of gouge using the program MudMaster indicates that the gouge underwent multiple generations of illite growth which may correspond to renewed episodes of fault motion. It is unlikely that fine illites experienced Ar loss resulting from protracted burial metamorphism under the Appalachian clastic wedge. The rocks around the Champlain Thrust have not experienced metamorphic conditions above 180 C as shown by conodont data, and should not have exceeded the illite closure temperature of ~200 C. Additionally, K/Ar dates on fine (<0.15 um) illite from two nearby Ordovician K-bentonites at a similar stratigraphic level give Carboniferous dates at 326 4 Ma and 302 4 Ma suggesting post Taconic illite grown possibly driven by Acadian or Alleghanian fluid flow. These K-bentonite illites show no evidence for pronounced periods of post-Carboniferous Ar loss and/or illite growth. Instead, we suggest that gouge dates reflect illite formation resulting from discrete periods of fault motion that persisted into Late Jurassic time. Mesozoic activity in the Northern Appalachian basin has also been documented by a number of apatite and zircon fission-track studies which argue for a period of region wide Middle Jurassic to Late Cretaceous unroofing driven by reactivation of major faults systems. Our fault gouge dates support this interpretation by providing evidence for post orogenic fault motion on the Champlain Thrust.

Meyer, E. E.; Eberl, D. D.; Ryan, P. C.

2010-12-01

248

VERTEBRATES OF FISH LAKE  

E-print Network

VERTEBRATES OF FISH LAKE CAUTION! FISH LAKE SCAVANGER HUNT RED HEADED is another majestic bird of Fish Lake. These birds can be seen perched at Fish Lake. CLUB-TAIL DRAGONFLY INSECTS OF FISH LAKE There are A LOT

Minnesota, University of

249

Wisconsin's Great Lakes Shipwrecks  

NSDL National Science Digital Library

What better way to beat the heat than to imagine diving into the deep, cool waters of Lake Superior (average temp: Ten degrees above freezing) without having to leave your desk. This exceptional shipwreck site, produced by the Wisconsin Historical Society and the UW Madison Sea Grant Institute, allows the visitor to pick her or his lake, Superior or Michigan, and explore the many shipwrecks that are chronicled there. The exhibits include photo galleries and video, taking the visitor up-close with these fascinating underwater artifacts. Deeper in the site is a section called Notes in the Field, where scientists involved in this summer's exploration of the Kate Kelly, a schooner that reefed between Milwaukee and Chicago in 1895, provide a daily log of their activities. Also off of this link is another link to the Kids' Corner, which provides all sorts of good information for kids and teachers about underwater archaeology and shipwrecks. This is definitely a site worth diving into.

250

This article was downloaded by: [J. Ellen Marsden] On: 28 December 2011, At: 07:04  

E-print Network

://www.tandfonline.com/loi/ujfm20 Lake Whitefish in Lake Champlain after Commercial Fishery Closure and Ecosystem Changes Seth J and Wildlife Service, Lake Champlain Fish and Wildlife Resources Office, 11 Lincoln Street, Essex Junction this article: Seth J. Herbst, J. Ellen Marsden & Stephen J. Smith (2011): Lake Whitefish in Lake Champlain

Marsden, Ellen

251

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research  

E-print Network

whitefish (Coregonus clupeaformis) in Lake Champlain Seth J. Herbst 1 , J. Ellen Marsden Rubenstein School from 151 lake whitefish (Coregonus clupeaformis) from Lake Champlain, 2009. Mean and systematic evaluation of precision and bias of age structures for Lake Champlain's unexploited lake whitefish population

Marsden, Ellen

252

January 2013 REQUEST FOR SOCIAL SCIENCE PROPOSALS Illinois-Indiana Sea Grant College Program  

E-print Network

to the Illinois and/or Indiana coastal areas of Lake Michigan: 1. Indicators of Great Lakes literacy and in Lake Michigan coastal areas Scope of projects can vary, i.e., projects could span the whole Great LakesJanuary 2013 � REQUEST FOR SOCIAL SCIENCE PROPOSALS Illinois-Indiana Sea Grant College Program

253

Archaea in Yellowstone Lake.  

PubMed

The Yellowstone geothermal complex has yielded foundational discoveries that have significantly enhanced our understanding of the Archaea. This study continues on this theme, examining Yellowstone Lake and its lake floor hydrothermal vents. Significant Archaea novelty and diversity were found associated with two near-surface photic zone environments and two vents that varied in their depth, temperature and geochemical profile. Phylogenetic diversity was assessed using 454-FLX sequencing (~51,000 pyrosequencing reads; V1 and V2 regions) and Sanger sequencing of 200 near-full-length polymerase chain reaction (PCR) clones. Automated classifiers (Ribosomal Database Project (RDP) and Greengenes) were problematic for the 454-FLX reads (wrong domain or phylum), although BLAST analysis of the 454-FLX reads against the phylogenetically placed full-length Sanger sequenced PCR clones proved reliable. Most of the archaeal diversity was associated with vents, and as expected there were differences between the vents and the near-surface photic zone samples. Thaumarchaeota dominated all samples: vent-associated organisms corresponded to the largely uncharacterized Marine Group I, and in surface waters, ~69-84% of the 454-FLX reads matched archaeal clones representing organisms that are Nitrosopumilus maritimus-like (96-97% identity). Importance of the lake nitrogen cycling was also suggested by >5% of the alkaline vent phylotypes being closely related to the nitrifier Candidatus Nitrosocaldus yellowstonii. The Euryarchaeota were primarily related to the uncharacterized environmental clones that make up the Deep Sea Euryarchaeal Group or Deep Sea Hydrothermal Vent Group-6. The phylogenetic parallels of Yellowstone Lake archaea to marine microorganisms provide opportunities to examine interesting evolutionary tracks between freshwater and marine lineages. PMID:21544103

Kan, Jinjun; Clingenpeel, Scott; Macur, Richard E; Inskeep, William P; Lovalvo, Dave; Varley, John; Gorby, Yuri; McDermott, Timothy R; Nealson, Kenneth

2011-11-01

254

ANALYSES OF ORGANIC AND INORGANIC CONTAMINANTS IN SALTON SEA FISH. (R826552)  

EPA Science Inventory

Chemical contamination of fish from the Salton Sea, a quasi-marine lake in Southern California, could adversely impact millions of birds using the Pacific Flyway and thousands of humans using the lake for recreation. Bairdiella icistia (bairdiella), Cynoscion xanthul...

255

A coupled lake-atmosphere model (CLAM) and its application to Lake Kinneret  

NASA Astrophysics Data System (ADS)

Kinneret is a 166-km2 lake located in Northern Israel, in the central part of the Jordan Valley, a corridor running from north to south, between the Galilee hills in the west and the Golan Heights in the east. Both the Galilee hills and the Golan Heights reach an elevation of about 400 m above mean sea level (MSL), and the lake is about -210 m (MSL). North of the lake is the mountainous area of the Hermon, culminating at about 2800 m (MSL). About 120 km south of it is the Dead Sea, which is about -410 m (MSL), and about 45 km west of it is the Mediterranean Sea. The complexity of the terrain, combined with relatively arid soil and various ground covers surrounding the lake, results in a very complicated system of atmospheric and lake processes. To understand this system, especially the processes affecting the atmosphere and lake dynamics and thermodynamics, and their effects on Lake Kinneret evaporation, a coupled lake-atmosphere model (CLAM) was developed and applied to the lake region. The CLAM is based on the Regional Atmospheric Modeling System (RAMS) and the oceanic S-coordinate Rutgers University Model (SCRUM). Energy, mass, and momentum are conserved at the interface between the atmosphere and the lake, and appropriate balance equations are applied there. In the atmospheric module, two nested grids are employed to simulate Northern Israel at a resolution of 4 x 4 km2, and the near-lake region at a resolution of 1 x 1 km 2. Synoptic conditions obtained from the National Meteorological Center (NMC) reanalysis are assimilated by the model. Soil moisture, which appears to have a significant impact on atmospheric circulation in this region, was transformed from the normalized difference vegetation index (NDVI). Observations collected during two summers above and inside the lake emphasize the good capability of CLAM to simulate surface fluxes and other microclimatic conditions, as well as lake temperature and currents. Although the lake is small (about 12-km wide and 22-km long), the micrometeorological conditions, lake currents and thermal structure, and the lake-surface heat fluxes vary spatially very significantly, even on a daily basis. It is found that the daily-mean wind curl, which is predominantly determined by the passage of the Mediterranean Sea breeze (MSB) over the lake, is mostly responsible for the gyres in the lake. The thermocline oscillation in the lake is mainly controlled by the surface elevation set up by the time-dependent winds. The intense MSB over the lake in the late afternoon pushes the heated surface water eastward, forces the deep, cooler water to be advected westward, and creates strong mixing in the lake, resulting in a higher temperature off the eastern shore and a lower temperature off the western shore. The variation of lake-surface temperature not only directly affects the atmospheric processes over the lake, but it also changes the wind field, which then influences hydrodynamic processes in the lake. An analytical model of the flow response to spatial variation of atmospheric cooling in coastal ocean was also developed in this study. This model is used to explain the contribution of the spatial variation of latent heat flux to the circulation in Lake Kinneret, and also the cyclonic flow, which is observed in many lakes and semi-enclosed coastal oceans.

Pan, Hai

1999-08-01

256

The discovery of stromatolites developing at 3570 m above sea level in a high-altitude volcanic lake Socompa, Argentinean Andes.  

PubMed

We describe stromatolites forming at an altitude of 3570 m at the shore of a volcanic lake Socompa, Argentinean Andes. The water at the site of stromatolites formation is alkaline, hypersaline, rich in inorganic nutrients, very rich in arsenic, and warm (20-24C) due to a hydrothermal input. The stromatolites do not lithify, but form broad, rounded and low-domed bioherms dominated by diatom frustules and aragonite micro-crystals agglutinated by extracellular substances. In comparison to other modern stromatolites, they harbour an atypical microbial community characterized by highly abundant representatives of Deinococcus-Thermus, Rhodobacteraceae, Desulfobacterales and Spirochaetes. Additionally, a high proportion of the sequences that could not be classified at phylum level showed less than 80% identity to the best hit in the NCBI database, suggesting the presence of novel distant lineages. The primary production in the stromatolites is generally high and likely dominated by Microcoleus sp. Through negative phototaxis, the location of these cyanobacteria in the stromatolites is controlled by UV light, which greatly influences their photosynthetic activity. Diatoms, dominated by Amphora sp., are abundant in the anoxic, sulfidic and essentially dark parts of the stromatolites. Although their origin in the stromatolites is unclear, they are possibly an important source of anaerobically degraded organic matter that induces in situ aragonite precipitation. To the best of our knowledge, this is so far the highest altitude with documented actively forming stromatolites. Their generally rich, diverse and to a large extent novel microbial community likely harbours valuable genetic and proteomic reserves, and thus deserves active protection. Furthermore, since the stromatolites flourish in an environment characterized by a multitude of extremes, including high exposure to UV radiation, they can be an excellent model system for studying microbial adaptations under conditions that, at least in part, resemble those during the early phase of life evolution on Earth. PMID:23308236

Faras, Mara E; Rascovan, Nicols; Toneatti, Diego M; Albarracn, Virginia H; Flores, Mara R; Poir, Daniel G; Collavino, Mnica M; Aguilar, O Mario; Vazquez, Martin P; Polerecky, Lubos

2013-01-01

257

Variation of Great Lakes Water Levels Derived from Geosat Altimetry  

NASA Technical Reports Server (NTRS)

A technique for using satellite radar altimetry data to estimate the temporal variation of the water level in moderate to large lakes and enclosed seas is described. Great Lakes data from the first 2 years of the U.S. Navy's Geosat Exact Repeat Mission (November 1986 to November 1988), for which there is an improved orbit, are used to demonstrate the technique. The Geosat results are compared to the lake level data collected by the Great Lakes Section, National Ocean Service, National Oceanic and Atmospheric Administration, and are found to reproduce the temporal variations of the five major lakes with Root-Mean-Square error (RMS) ranging from 9.4 to 13.8 cm and a combined average of 11.1 cm. Geosat data are also analyzed for Lake St. Clair, representing a moderate-sized lake, with a resulting rms of 17.0 cm. During this study period, the water level in the Great Lakes varied in a typical annual cycle of about 0.2 m (0.5 in for Lake Ontario) superimposed on a general decline of approximately 0.5 m. The altimeter data reproduced the general decline reasonably well for all the lakes, but the annual cycle was obscured in some lakes due to systematic errors in the altimeter data. Current and future altimetry missions will have markedly improved accuracy which will permit many moderate (25 km diameter) or larger lakes or enclosed seas to be routinely monitored.

Morris, Charles S.; Gill, Stephen K.

1994-01-01

258

The Disappearing Aral Sea  

NSDL National Science Digital Library

In just 30 years, the Aral Sea has lost more than 60 percent of its water. Barring change, it may disappear entirely by 2020. In this visualization, satellite images dating from 1973 to 2000 show how water diverted from this inland lake for agriculture has caused it to shrink considerably over a short period of time. The feature can be run as an animation or as a series of slides. A background essay and discussion questions are included.

259

Description of Spring Roost Trees Used by Female Indiana Bats (Myotis sodalis) in the Lake Champlain Valley of Vermont and New York  

Microsoft Academic Search

Extensive effort has been directed at the roosting ecology of the federally endangered Indiana bat (Myotis sodalis) during the maternity season; however, spring roosting ecology has received much less attention. In April 2002, radio transmitters were attached to the back of 19 female Indiana bats as they emerged from a hibernaculum in northeastern New York. Thirty-nine roost trees were found

ERIC R. BRITZKE; ALAN C. HICKS; SUSANNA L. VON OETTINGEN; SCOTT R. DARLING

2006-01-01

260

Lake Nipigon  

NSDL National Science Digital Library

These recent postings from the Canada Centre for Remote Sensing's (CCRS) "Images of Canada" series provide an interesting introduction to remote sensing techniques and the history of landforms, both natural and human-made. The Landsat image of Ontario's Lake Nipigon, a name meaning "deep, clear lake," is viewable in two sizes and is accompanied by text and other remote images on the structural geology, rock types, recent forest fires, and forestry research around the lake. The CCRS was last mentioned in the May 24, 2000 Scout Report for Science and engineering.

2001-01-01

261

Metagenomic sequencing of two salton sea microbiomes.  

PubMed

The Salton Sea is the largest inland body of water in California, with salinities ranging from brackish freshwater to hypersaline. The lake experiences high nutrient input, and its surface water is exposed to temperatures up to 40C. Here, we report the community profiles associated with surface water from the Salton Sea. PMID:24459270

Hawley, Erik R; Schackwitz, Wendy; Hess, Matthias

2014-01-01

262

Satellite Altimetry for Monitoring Lake Level Changes  

Microsoft Academic Search

Accurate and continuous monitoring of lakes and inland seas is possible since 1991 thanks to the recent missions of satellite altimetry (Topex-Poseidon, ERS-1, ERS-2, Jason-1 and Envisat). Global processing of the data of these satellites could provide temporal and spatial times series of lakes water level from 1991 to 2003 on the whole Earth with a decimeter precision. The response

J.-F. Cretaux; A. Kouraev; M. Berge-Nguyen; A. Cazenave; F. Papa

263

Lake Study  

NSDL National Science Digital Library

Lake Study for Windows is a two-part simulation designed to involve students with the scientific method. It allows them to collect data, formulate hypotheses, and test the hypotheses with controlled experiments.

264

Circulation and sedimentation in a tidal-influenced fjord lake: Lake McKerrow, New Zealand  

NASA Astrophysics Data System (ADS)

Lake McKerrow is a tide-influenced fjord lake, separated from the open sea by a Holocene barrier spit. Fresh, oxygenated waters of the epilimnion overlie saline, deoxygenated waters of the hypolimnion. During winter, water from the Upper Hollyford River interflows along the pycnocline, depositing coarse silt on the steep delta and transporting finer sediment down-lake. An extensive sub-lacustrine channel system on the foreset delta slope is possibly maintained by turbidity currents. Saline waters of the hypolimnion are periodically replenished. During high tides and low lake levels saline water flows into the lake and downslope into the lake basin as a density current in a well defined channel.

Pickrill, R. A.; Irwin, J.; Shakespeare, B. S.

1981-01-01

265

QUATERNARY DIVERGENCE AND HOLOCENE SECONDARY CONTACT VIA THE NORTHWEST PASSAGE  

E-print Network

: one each in New Jersey, Lake Champlain, and the Pacific Northwest. The distribution of isozyme, Lake Champlain, and the Great Lakes was used to reconstruct a North American history. One subset suggest that an early post-glacial vicariance event is implicated in the history of the Lake Champlain

Lintilhac, Philip M.

266

CATASTROPHIC FLOODING OF THE BLACK SEA  

Microsoft Academic Search

? Abstract Decades of seabed mapping, reflection profiling, and seabed sampling reveal that throughout,the past two million years the Black Sea was predominantly,a freshwater lake interrupted only briefly by saltwater invasions coincident with global sea level highstand. When,the exterior ocean lay below,the relatively shallow sill of the Bosporus outlet, the Black Sea operated in two modes. As in the neighboring

William B. F. Ryan; Candace O. Major; Gilles Lericolais; Steven L. Goldstein

2003-01-01

267

Ice-dammed lakes and rerouting of the drainage of northern Eurasia during the Last Glaciation  

Microsoft Academic Search

During the Quaternary period, ice sheets centred over the Barents and Kara seas expanded several times onto mainland Russia and blocked northflowing rivers, such as the Yenissei, Ob, Pechora and Mezen. Large ice-dammed lakes with reversed outlets, e.g. toward the Caspian Sea, formed south of these ice sheets. Some lakes are reconstructed from shorelines and lacustrine sediments, others mainly from

Jan Mangerud; Martin Jakobsson; Helena Alexanderson; Valery Astakhov; Garry K. C Clarke; Mona Henriksen; Christian Hjort; Gerhard Krinner; Juha-Pekka Lunkka; Per Mller; Andrew Murray; Olga Nikolskaya; Matti Saarnisto; John Inge Svendsen

2004-01-01

268

Salton, A Sea of Controversy  

NSDL National Science Digital Library

The Salton Sea is an “accidental” lake that receives used irrigation water from the Colorado River. Humans have profoundly altered the area’s ecosystems. The Salton Sea is important for wildlife and recreation, but is now saltier than the ocean. How might it be saved? This case examines the Salton Sea’s problems and uncertain future. The case would be suitable for introductory environmental, biology, geography and geology classes, and courses dealing with land use, water resources, agriculture, birds or fish, ecosystems, and government policy.

Vessey, Kristin B.

1999-01-01

269

Variability of transparent organic particles in Arctic floodplain lakes  

NASA Astrophysics Data System (ADS)

The Mackenzie River in the North American Arctic courses into the Beaufort Sea, the outlet of a watershed that drains a vast swath of the western Canadian landscape. At the river's mouth the Mackenzie Delta is a broad floodplain peppered with roughly 45,000 lakes carved into the permafrost. Depending on their connectivity to the river, these floodplain lakes have different mixtures of organic compounds, and such differences affect carbon cycling and sediment processes in the lakes.

Schultz, Colin

2013-02-01

270

Lake Biwa and the ocean: geochemical similarity and difference  

Microsoft Academic Search

The average composition of water, bottom sediments, manganese (Mn) crusts, and Mn concretions from Lake Biwa (the largest\\u000a freshwater lake in Japan) are re-examined, in conjunction with those of seawater, oceanic pelagic clay, and deep-sea Mn nodules.\\u000a The purpose is to gain additional insights into the geochemical behaviors of elements in Lake Biwa and the ocean, which are\\u000a quite different

Yuan-Hui Li; Yoshiki Sohrin; Takejiro Takamatsu

2011-01-01

271

Biology of penaeid prawns in the Suez Canal lakes  

Microsoft Academic Search

A study was made from January 1988 to March 1989 of the penaid prawns in the Great Bitter Lake and Lake Timsah located in the central part of the Suez Canal. Two species of Red Sea origin were investigated,Metapenaeus stebbingi andTrachypenaeus curvirostris; the former is by far the commoner. Both species displayed seasonal breeding over the period April to October,

A. A.-F. A. Gab-Alla; R. G. Hartnoll; A.-F. Ghobashy; S. Z. Mohammed

1990-01-01

272

Principles of lake sedimentology  

SciTech Connect

This book presents a comprehensive outline on the basic sedimentological principles for lakes, and focuses on environmental aspects and matters related to lake management and control-on lake ecology rather than lake geology. This is a guide for those who plan, perform and evaluate lake sedimentological investigations. Contents abridged: Lake types and sediment types. Sedimentation in lakes and water dynamics. Lake bottom dynamics. Sediment dynamics and sediment age. Sediments in aquatic pollution control programmes. Subject index.

Janasson, L.

1983-01-01

273

Investigating sedimentary rock deposition and weathering in Mawikwe Bay Sea Caves  

NSDL National Science Digital Library

A field investigation to the Mawikwe Bay Sea Caves of northern Wisconsin along Lake Superior in the winter. Students will investigate deposition of sedimentary rocks and weathering of the rocks to produce sea caves.

274

ENVIRONMENTAL PROBLEMS IN TWO EGYPTIAN SHALLOW LAKES SUBJECTED TO DIFFERENT LEVELS OF POLLUTION  

Microsoft Academic Search

The two study areas are Lake Mariut and the Nozha Hydrodrome. The water of Lake Mariut is pumped to the Mediterranean Sea. It is the heavily polluted basin in Egypt receiving huge amounts of contaminated drainage waters and untreated domestic and industrial wastes. The Hydrodrome was separated in 1939 from Lake Mariut and became polluted in recent years from the

Massoud A. H. Saad; A. M. Safty

2004-01-01

275

Nannoplankton of Marine Origin from Great Bear Lake in the Northwest Territories of Canada  

Microsoft Academic Search

GREAT Bear Lake is situated on the Arctic Circle at a point where the Pre-Cambrian Shield emerges from the adjoining Cretaceous formations. The present lake surface is 143 m above sea level, and because the maximum depth is 542 m there is a cryptodepression of 309 m. The shape of the lake could be described as amoeboid with five arms

A. S. Bursa; L. Johnson

1967-01-01

276

Low-Head Barrier Dams Restrict the Movements of Fishes in Two Lake Ontario Streams  

Microsoft Academic Search

The Great Lakes Fishery Commission (GLFC) is considering greater use of low-head barrier dams on stream tributaries of the Laurentian Great Lakes to control populations of sea lampreys Petromyzon marinus. The impact of these barriers on nontarget fishes is not known. A markrecapture study on four Lake Ontario streams examined movements of fishes in streams with (barrier) and without (reference)

L. M. Porto; R. L. McLaughlin; D. L. G. Noakes

1999-01-01

277

Great Lakes Climate and Water Movement. Earth Systems - Education Activities for Great Lakes Schools (ES-EAGLS).  

ERIC Educational Resources Information Center

This activity book is part of a series designed to take a concept or idea from the existing school curriculum and develop it in the context of the Great Lakes using teaching approaches and materials appropriate for students in middle and high school. The theme of this book is Great Lakes climate and water movement. Students learn about land-sea

Miller, Heidi, Ed.; Sheaffer, Amy L., Ed.

278

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

279

Lake Powell  

NASA Technical Reports Server (NTRS)

The white ring around Lake Powell tells the story. The surface is down 98 feet. This is critical, because Powell, Lake Mead, and other lakes along the Colorado River provide water for millions of people in five states. We are in the eighth year of a drought on the Colorado River. This year was the driest year ever reported in Southern California, and there is a severe drought in Northern California, down to less than 30-percent of snow pack. This ASTER image of part of Lake Powell was acquired in 2001. The gray area depicts the shrunken, reduced 2007 lake extent compared to the extended, larger black area in 2001.

The image covers an area of 24 x 30 km, and is centered near 37.1 degrees north latitude, 111.3 degrees west longitude.

The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

2007-01-01

280

Release date December 9, 2011 for 2012-2013 Year 1 RACC Call for Proposals  

E-print Network

for Faculty Research on Adaptation to Climate Change in the Lake Champlain Basin: New Understanding through with the VT EPSCoR research on adaptation to climate change in the Lake Champlain Basin with insights through

Hayden, Nancy J.

281

UVM'S BEST KEPT SECRETS And we're letting them out!  

E-print Network

the beauty of a Burlington sunset and an incredible view of Lake Champlain. Play Broomball: Run around waterfront. Check out Lake Champlain native species and have fun in the touch tank. Thanks for coming

Hayden, Nancy J.

282

RACC WORKING PAPER SERIES Impacts of Land Managers' Decisions on Landuse Transition within Missisquoi  

E-print Network

Change in the Lake Champlain Basin: New Understanding through Complex Systems Modeling (RACC) University Watershed, one of the tributary watersheds of Lake Champlain, is mainly located within the U.S. state

Beckage, Brian

283

REGISTER TODAY! LEARN.UVM.EDU/OLLI 802.656.2085 Become an OLLI at UVM member and register for courses  

E-print Network

. Watercolor II, Spring 2013 PREVIEW FOR SUMMER 2014 Kayaking on Lake Champlain Painting with Acrylics Archaeology Tour of Lake Champlain Shipwrecks Plein Air Watercolor Tour of UVM Horticulture Farm Bridging

Hayden, Nancy J.

284

By WILLIAM CONVERSE KENDALL Ichthyologist, United States Bureau of Fisheries  

E-print Network

-Continued. 303 Fresh-water flsheries., , n nn 306 Icefish or smelt of Lake Champlain _ 307 Smelt fishery of Lake Champlain_nn_ 308 Quality and utilization _ 308 Fish-cultural propagation; n n .. __ 309 Anatomy

285

Healthy Coastal Ecosystems Focus Team Report 2011  

E-print Network

with landowners to eradicate 1,500 acres of Phragmites along the state's coastal waters. #10258 LAKE CHAMPLAIN in the vicinity of Lake Champlain. The training paid off in August 2008, when a Canadian citizen declared her

286

WorldMusicExploration GarrettGarciaandKylerRuane,ProgramDirectors  

E-print Network

Champlain, in September, and outdoor music events on Church Street and at Lake Champlain. B.) Students who Burlington offers. Free concerts include events at Southwick Recital Hall, Grand Point North Festival at Lake

Hayden, Nancy J.

287

Media Inquiries: Department of Communications Michael Walker, 212-769-5766; walker@amnh.org  

E-print Network

after the Arizona wildfires of last year? Are non-native fish endangering brook trout in Lake Champlain Hero, Vermont o Found that the eggs of native brook trout populations in the Lake Champlain basin were

Walter, M.Todd

288

Sea Turtles  

NSDL National Science Digital Library

Sea World informational resource on all eight species of sea turtles. Excellent introduction to sea turtles including information on their classification, habitat, diet, reproduction, and much more. Includes photographs and illustrations throughout. Features two teaching activities for grades K-2.

2012-07-26

289

Lake acidification  

SciTech Connect

This paper examined a National Research Council (NRC) report called Acid Deposition: Long-Term Trends. The report has been the final word on acid deposition as the cause of acidification of lakes. The authors considered it important that the tentative nature of this report be kept in perspective so that the work of the NRC would promote rather than inhibit scientific inquiry on the lake acidification issue. In this spirit, this report proposed that degradation of storm damaged trees could increase the acidity of the forest humus and as a result the ground water which would fed local streams and lakes. They proposed that extensive forest blowdown could be a factor in acidification of surface waters.

Dobson, J.E.; Peplies, R.W.; Rush, R.M.

1987-06-01

290

Monsoon variability of the East Asian mainland during the last glacial\\/interglacial cycle as recorded from varved lake sediments (Invited)  

Microsoft Academic Search

Three high-resolution lake records from eastern China have been investigated. Lake Sihailongwan (SHL) and Lake Erlongwan from Jilin province, NE China, provide long varved sediment records for the last 65 ka and 37 ka, respectively from the East Asian mainland, whilst Lake Huguangyan from the northern coast of the South China Sea yields an uninterrupted archive of the subtropical monsoon

J. Mingram; M. Stebich; G. Schettler; J. Han; G. Chu; P. Rioual; Q. Liu; P. Dulski; N. Nowaczyk; U. Frank; A. Lcke; H. You; A. Spangenberg; J. Liu; A. Brauer

2009-01-01

291

Uplift of the Lake Ladoga and Lake Onega region  

NASA Astrophysics Data System (ADS)

The north-west region of the Europe (the Baltic shield) has the well-known phenomena of the postglacial uplift. Parameters of this uplift were evaluated many times in various projects (e.g. Baltic Sea Level, BIFROST), from permanent GPS station data, and by tide gauge recordings and repeated precise levelling. In addition to the general uplift pattern that is centered at the northern part of the Gulf of Bothnia (~10 mm/year) and smoothly reduced towards the edge of the Baltic shield, an additional maximum (up to ~7 mm/year) at the north of the Lake Ladoga was anticipated by geodetic leveling (Kakkuri, Poutanen 1997) and by GPS observations (Prilepin et al. 2002). A new data of permanent and campaign-wise GPS observations during 1999-2009 were used to estimate the uplift values in the area of Lake Ladoga and Lake Onega. The height component of GPS points near these lakes have anomalous large uplift values (3 - 6 mm/year) centered to the north of Lake Ladoga. In this determination, permanent IGS and EPN stations in SE Finland and Russia have their expected values of uplift for this region (2 - 5 mm/year). The horizontal components of these points have the usual east-northeast trend. References Kakkuri J., Poutanen M., 1997. Geodetic determination of the surface topography of the Baltic Sea. Marine Geodesy, vol. 20, 4, 1-10. Prilepin, M. T., Mishin, A. V., Kaban, M. K., Baranova, S. M. (2002) Study of the Baltic Shield Geodynamics from GPS data. Izvestiya, Physics of the Solid Earth, vol. 38, 9, 756-764.

Galaganov, O.; Guseva, T.; Rosenberg, N.; Gorshkov, V.; Scherbakova, N.; Poutanen, M.

2010-05-01

292

Lake Biwa as a topical ancient lake  

Microsoft Academic Search

Present knowledge concerning the Japanese ancient Lake Biwa is briefly summarized, and extant and potential threats to its well-being are documented. From this example of Lake Biwa, strengths and weaknesses in our knowledge of other ancient lakes and the problems that they face were identified. Several areas of concern were evident.Knowledge of the geological history of ancient lakes is uneven,

A. Rossiter

2000-01-01

293

Paleoceanography and glacial runoff along the St. Lawrence valley system  

SciTech Connect

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

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

1992-01-01

294

Modern hydrology and late Holocene history of Lake Karakul, eastern Pamirs (Tajikistan): A reconnaissance study  

Microsoft Academic Search

Lake Karakul in the Pamirs (Tajikistan) is a deep brackish-water lake in a closed basin at almost 4000m above sea level. Water samples from the catchment area and Lake Karakul, and a 104-cm sediment core from its shallow eastern sub-basin, were investigated and provide a first lake record from the region spanning the last 4200cal yr BP. Multi-proxy analyses revealed

Steffen Mischke; Ilhomjon Rajabov; Nailya Mustaeva; Chengjun Zhang; Ulrike Herzschuh; Ian Boomer; Erik T. Brown; Nils Andersen; Amy Myrbo; Emi Ito; Michael E. Schudack

2010-01-01

295

Lake Victoria  

NSDL National Science Digital Library

This online article, from "The Biodiversity Crisis: Losing What Counts", provides insight into how human behavior has put one of the world's largest ecosystems close to death. It covers the astonishingly diverse cichlid species that live only in Lake Victoria and changes to the ecosystem brought about by the introduction of a non-native species.

296

Global Change in the Great Lakes: Scenarios.  

ERIC Educational Resources Information Center

The Ohio Sea Grant Education Program has produced this series of publications designed to help people understand how global change may affect the Great Lakes region. The possible implications of global change for this region of the world are explained in the hope that policymakers and individuals will be more inclined to make responsible decisions

Garrison, Barbara K., Ed.; Rosser, Arrye R., Ed.

297

Water Pollution in the Durankulak Lake, Bulgaria  

Microsoft Academic Search

The importance of the wetlands as ecosystem types consists in the stable maintenance of high biodiversity in the limited space of the ecotone. For this reason the system can be relatively easily studied and managed, and a great number of plant and animal species can be easily protected. The Durankulak Lake situated in close proximity to the Black Sea is

Ivanka Dimitrov; Vihra Hainadjiev

298

Lake Sihwa tidal power plant project  

Microsoft Academic Search

A Tidal Power Plant (TPP) is being constructed in the middle section of the existing Lake Sihwa dike located near the southern Incheon Port in Korea. The project, which will be completed in 2010, is to harness the largest tidal energy in the Kyeonggi Bay in the eastern Yellow Sea. While noting the current progress in terms of plant construction,

Young Ho Bae; Kyeong Ok Kim; Byung Ho Choi

2010-01-01

299

Epidemiology of great lakes bald eagles  

Microsoft Academic Search

Historical data are provided to support the hypothesis that organochlorine chemicals introduced into the Great Lakes ecosystem following World War II are the cause of reproductive loss among bald eagles (Haliaeetus leucocephalus) in the basin. This is supported with data on concurrent population fluxes of extrabasin North American bald eagle populations and the European white?tailed sea eagle (Haliaeetus albicillus.) where

Theo Colborn

1991-01-01

300

Middle Ordovician Section at Crown Point Peninsula Charlotte Mehrtens, University of Vermont  

E-print Network

of the Chazy Group in the Lake Champlain Valley was defined by Oxley and Kay (1959). Welby (1962) provides descriptions of Chazy Group strata in the northern Lake Champlain Valley. Biostratigraphic correlations Lake Champlain Valley, the basal Chazy units are clearly in unconformable contact with tilted, eroded

Soja, Constance M.

301

33 CFR 165.171 - Safety Zones for fireworks displays and swim events held in Coast Guard Sector Northern New...  

...regulated area includes all waters of Lake Champlain in the vicinity of Shelburne...includes all waters of Malletts Bay on Lake Champlain, Vermont within the following...includes all waters of Treadwell Bay on Lake Champlain in the vicinity of...

2014-07-01

302

[Wang, D., Dorioz, J-M., Trevisan, D., Braun, D.C., Windhausen, L.J., and Vansteelant, J-Y. 2004. Using a landscape approach to interpret diffuse phosphorus pollution and assist with  

E-print Network

quality management in the basins of Lake Champlain (Vermont) and Lac Léman (France). pp. 159-190 IN T.O. Manley, P.L. Manley, and T.B. Mihuc. (eds.) Lake Champlain: Partnerships and Research in the New POLLUTION AND ASSIST WITH WATER QUALITY MANAGEMENT IN THE BASINS OF LAKE CHAMPLAIN (VERMONT) AND LAC L?MAN

Wang, Deane

303

SITING OBSERVERS ON TERRAIN Wm Randolph Franklin  

E-print Network

algorithm. Various experiments with varying parameters were performed on the Lake Champlain West cell, viewshed, line of sight, multiple observers Contents 1 Introduction 2 2 Detailed Process 3 3 Lake Champlain, and provided the Lake Champlain W data used in this paper. Ray (1994) presented new algorithms

Franklin, W. Randolph

304

Extended Abstract Approximating Visibility  

E-print Network

for Figure 4 June 1, 2000, 21:3 #12;Franklin Approximating Visibility 7 Figure 6: Lake Champlain W Cell 2.2 Lake Champlain West The second test case was the £¥¤§¦¨£T©U£¥¤§¦A£ Lake Champlain West level-1 DEM from

Franklin, W. Randolph

305

Vermont EPSCoR Track-1 Research Infrastructure Award for  

E-print Network

Change in the Lake Champlain Basin: New Understanding through Complex Systems Modeling NSF EPS# 1101317, hypothesis driven research questions about the Lake Champlain Basin as a coupled human and natural system EPSCoR's current research in complex systems modeling of the many extant data sets of the Lake Champlain

Hayden, Nancy J.

306

To Brunswick Folsom Lake  

E-print Network

92 To Brunswick Lake Tahoe Folsom Lake Clear Lake Indian Valley Reservoir Lakeport CALPELLA MASONITE UPPER LAKE LUCERNE WILLIAMS MERIDAN CORTINA PEASE BARRY BOGUE OLIVEHURST HARTER Marysville Yuba GARCIA POINT ARENA GUALALA ANNAPOLIS FORT ROSS SONOMA Lake Sonoma MONTE RIO SALMON CREEK CALISTOGA

307

Changing Planet: Warming Lakes  

NSDL National Science Digital Library

The video addresses impact of warming temperatures on major lakes of the world with specific focus on Lake Superior and Lake Tanganyika. It discusses the science of water stratification and its impact on lake ecosystems and on human populations whose livelihoods depend on the lakes.

Learn, Windows T.; National Earth Science Teachers Association (NESTA)

308

Towards Limnological Modeling of the Dead Sea: Mass and Heat Balances  

Microsoft Academic Search

The Dead Sea (DS), the lowest place on Earth, is a hypersaline terminal lake with a unique composition. During the 20th century, the DS level has dropped by more than 20 meters, and presently it is about 417 meters below mean sea level. The decline in the DS level is a manifestation of the negative water balance of the lake,

309

Research to Guide Use of Barriers, Traps, and Fishways to Control Sea Lamprey  

Microsoft Academic Search

This paper provides a rigorous and directed research framework for fostering innovations in the design, implementation, and operation of barriers, traps, and fishways used to control the sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes. It was developed to support the Great Lakes Fishery Commission's milestone pledging to decrease reliance on chemical lampricides and achieve 50% of sea lamprey

Robert L. McLaughlin; Andrew Hallett; Thomas C. Pratt; Lisa M. OConnor; D. Gordon McDonald

2007-01-01

310

Aral Sea Basin Evolution: Geodynamic Aspect  

Microsoft Academic Search

\\u000a The Aral Sea lies in the Aral-Sarykamysh depression, which is bordered by the low plains of Central Asia. The climate is continental\\u000a and extremely dry, and surface runoff is virtually zero. Since direct precipitation over the lake comprises only 10% of the\\u000a water budget, lake-level fluctuations are largely determined by changes in inflow from the Amu Darya and Syr Darya

Bakhtiar Nurtaev

311

Great Lakes  

USGS Publications Warehouse

The wild plants and animals and the natural systems that support them in the Great Lakes region are valuable resources of considerable local, regional, and national interest. They are also, in part, transboundary resources that the U.S. shares with its Canadian neighbors to the north. The way these resources are changing over time is inadequately known and is a concern for resource users and for those charged with managing and protecting these unique and valuable resources. This chapter describes the wild plants and animals and the systems that support them in the Great Lakes region; addresses their condition; and points out the gaps in our knowledge about them that, if filled, would aid in their conservation and appropriate use.

Edsall, Thomas A.

1998-01-01

312

A post-Calumet shoreline along southern Lake Michigan  

USGS Publications Warehouse

The southern shore of Lake Michigan is the type area for many of ancestral Lake Michigan's late Pleistocene lake phases, but coastal deposits and features of the Algonquin phase of northern Lake Michigan, Lake Huron, and Lake Superior are not recognized in the area. Isostatic rebound models suggest that Algonquin phase deposits should be 100 m or more below modern lake level. A relict shoreline, however, exists along the lakeward margin of the Calumet Beach that was erosional west of Deep River and depositional east of the river. For this post-Calumet shoreline, the elevation of basal foreshore deposits east of Deep River and the base of the scarp west of Deep River indicate a slightly westward dipping water plane that is centered at ???184 m above mean sea level. Basal foreshore elevations also indicate that lake level fell ???2 m during the development of the shoreline. The pooled mean of radiocarbon dates from the surface of the peat below post-Calumet shoreline foreshore deposits indicate that the lake transgressed over the peat at 10,560 ?? 70 years B.P. Pollen assemblages from the peat are consistent with this age. The elevation and age of the post-Calumet shoreline are similar to the Main Algonquin phase of Lake Huron. Recent isostatic rebound models do not adequately address a high-elevation Algonquin-age shoreline along the southern shore of Lake Michigan, but the Goldthwait (1908) hinge-line model does. ?? 2006 Springer Science+Business Media B.V.

Capps, D. K.; Thompson, T. A.; Booth, R. K.

2007-01-01

313

The large lake ecosystems of northern Canada  

Microsoft Academic Search

The Great Lakes of northern Canada are relatively understudied ecosystems in comparison to the better-investigated Laurentian Great Lakes. This chain of lakes extends north from Lake Winnipeg (a shallow prairie lake) to Wollaston Lake and Lake Athabasca (moderately deep arboreal lakes) to Great Slave Lake (a deep subarctic lake) to Great Bear Lake (a deep lake located in the Arctic

M. S Evans

2000-01-01

314

Salton sea project, phase 1  

NASA Astrophysics Data System (ADS)

A feasibility study was made for a salt gradient solar pond power plant in or near the Salton Sea of California. The conclusions support continuance 5-MWe proof-of-concept experiment, and ultimate construction by an electric utility company of a 600-MWe plant. The Solar Pond concept would be an environmental benefit to the Salton Sea by reversing the increasing salinity trend. The greatest cost drivers are the lake dike construction and pond sealing. Problems to be resolved include method of brine production from Salton Sea water for the first unit (which requires evaporation pond area and time), the high turbidity and color content of the Salton Sea water (which requires pretreatment), and other questions related to pond permeability, bio-activity and soil/brine chemical reactions. All technical and environmental problems appear solvable and/or manageable if care is taken in mitigating impacts.

Peelgren, M. L.

1982-01-01

315

Seiche oscillations in Lake Baikal  

NASA Astrophysics Data System (ADS)

The variations in the free surface of Lake Baikal at three stations (Bol'shie Koty, Listvyanka, and Baikal'sk) are measured. A modern recording method and an advanced technique of record processing are used. Based on 1-year-long observation data, the amplitudes of seiche oscillations and their seasonal changes are analyzed. It is found, in particular, that 67-min seiches are manifested in different seasons. Numerical calculations of seiches in Lake Baikal are made with the use of up-to-date bathymetric data on one-dimensional, plan, and spherical models. Spatial structures of oscillations with periods of 277, 152, 84, 67, and 59 min, corresponding to the well-expressed peaks of power spectral density, are studied. It is shown that the first four periods correspond to uninodal, binodal, trinodal, and quadrinodal longitudinal seiche modes of Lake Baikal. The periods of three solutions can correspond to the value of 59 min. The first of them is the seiche of the lake's South Basin, and two others are characterized by significant amplitude growth in the Small Sea and Chivyrkui Bay.

Smirnov, S. V.; Kucher, K. M.; Granin, N. G.; Sturova, I. V.

2014-01-01

316

Evidence For A Series Of Large Freshwater Discharge Events To The North Atlantic Immediately Preceding The Younger Dryas  

NASA Astrophysics Data System (ADS)

Sedimentary evidence including a thick sand unit between two rhythmically laminated glacial lacustrine clay units in the northern Champlain Valley of New York State indicates that a flood was directed through the valley during the last deglaciation. This flood occurred when ice-marginal retreat north of the Adirondack Uplands allowed the confluence of Glacial Lakes Iroquois (Ontario Basin) and Vermont (Champlain Valley). A rough discharge estimate of 0.16 Sv has been calculated for the flood. There is also evidence that this event was preceded by a smaller flood with an estimated discharge of 0.11 Sv. Both floods would have been directed southward to the North Atlantic through the Hudson Valley. Varve counts from the northern Champlain basin indicate that these floods occurred 150 - 300 years before the Champlain Sea marine incursion. Radiocarbon ages from terrestrial macrofossils date these floods to about 13,000 calibrated years B.P. A third flood event (estimated at about 0.10 Sv) was caused by ice retreat north of the St. Lawrence Lowland, and was immediately followed by the incursion of the Champlain Sea. This flood would have been directed through the Gulf of St. Lawrence sometime between 12,850 - 12,700 calibrated years B.P., about the time of initiation of the Younger Dryas. This was also the beginning of the re-routing of all Great Lakes discharge (estimated at around 0.05 Sv) from the Hudson Valley to the Gulf of St. Lawrence. A brief re-occurrence of freshwater ostrocodes in early Champlain Sea sediments may indicate that another freshwater flood, perhaps originating from the Great Lakes, discharged into the North Atlantic through the Gulf of St. Lawrence.

Rayburn, J. A.; Franzi, D. A.; Knuepfer, P. L.; Cronin, T. M.; Berke, M. A.

2005-12-01

317

Bathymetry of Bonnie Doone Lake, Kornbow Lake, Mintz Pond, and Glenville Lake, Cumberland County, North Carolina, 1996-98  

USGS Publications Warehouse

Bathymetric surveys were conducted at four water-supply impoundments of Little Cross Creek in Cumberland County, North Carolina. The surveys were conducted in April 1996 at Mintz Pond and Glenville Lake, and in January 1998 at Bonnie Doone Lake and Kornbow Lake. The resulting bathymetric maps are the first to cover the entire range in depth for these reservoirs and provide a framework for future evaluations of bathymetry and storage capacity. Bathymetric maps were constructed from depth and position data collected at each reservoir. A boat-mounted, research-grade fathometer was used to record water depths with a vertical accuracy of 0.1 foot. At Mintz Pond and Glenville Lake, position was measured by using a wide-band laser tracking system interfaced with a total station survey instrument. This positioning method required multiple land-based control points to be established and was hampered by line-of-sight restrictions between the control points and the boat. At Bonnie Doone Lake and Kornbow Lake, a global positioning system was used to collect differentially corrected location data. This positioning method enabled more rapid data collection, eliminated the need for land-based control points, and provided improved data coverage. Spillway elevations range from 172.8 feet above mean sea level at Bonnie Doone Lake to 113.1 feet at Glenville Lake. Surface area and storage volume were computed for each reservoir and were related to water-surface elevations at 1-foot intervals. The combined surface acreage of the four Little Cross Creek reservoirs at their full-pool elevations is 120.97 acres, consisting of 21.20 acres at Bonnie Doone Lake, 47.09 acres at Kornbow Lake, 15.56 acres at Mintz Pond, and 37.12 acres at Glenville Lake. The four reservoirs have a combined usable storage capacity of 674.91 acre-feet, which is the sum of 127.93 acre-feet in Bonnie Doone Lake, 320.62 acre-feet in Kornbow Lake, 53.25 acre-feet in Mintz Pond, and 173.11 acre-feet in Glenville Lake.

Giorgino, M. J.; Strain, R. E.

1999-01-01

318

Mono Lake, California  

NSDL National Science Digital Library

This Sierra Webpage is dedicated to Mono Lake, CA. It offers a brief description of Mono Lake, including photos and sightseeing tips, and features numerous writings by Mono Lake Park Ranger David Carle. Subjects include the Mono Lake environment, visiting the lake, and the water issue. An entry of particular interest is Strange Water- Mono Lake Gourmet: An Unusual Recipe. It includes 'Mock Mono Lake Soup' and 'Tufa Porridge Extraordinaire'- two recipes designed to illustrate the composition of Mono Lake and the chemical processes involved in tufa formation.

Webpage, Sierra

319

An event-driven phytoplankton bloom in southern Lake Michigan observed by satellite.  

SciTech Connect

Sea-viewing Wide Field-of-View Sensor (SeaWiFS) images from June 1998 show a surprising early summer phytoplankton bloom in southern Lake Michigan that accounted for approximately 25% of the lake's annual gross offshore algal primary production. By combining the satellite imagery with in situ measurements of water temperature and wind velocity we show that the bloom was triggered by a brief wind event that was sufficient to cause substantial vertical mixing even though the lake was already stratified. We conclude that episodic events can have significant effects on the biological state of large lakes and should be included in biogeochemical process models.

Lesht, B. M.; Stroud, J. R.; McCormick, M. J.; Fahnenstiel, G. L.; Stein, M. L.; Welty, L. J.; Leshkevich, G. A.; Environmental Research; Univ. of Chicago; Great Lakes Research Lab.

2002-04-15

320

Authigenic carbonate precipitation in Lake Acigl, a hypersaline lake in southwestern Turkey  

NASA Astrophysics Data System (ADS)

Lake Acigl (Bitter Lake) is a hypersaline lake in southwestern Turkey at an elevation of 836 m above sea level showing authigenic precipitation of several different carbonate mineral phases. It is a perennial lake and closed drainage basin where a semiarid continental climate dominates. Due to the extreme water chemistry (salinity 8-200 mg/l; SO4 112-15232 mg/l; Cl 290-35320 mg/l; Mg, 82-3425 mg/l; Ca 102-745 mg/l) unique microorganisms flourish in the lake. We studied microbial diversity from enrichment cultures and performed precipitation experiments using similar water chemistry and adding bacterial enrichment cultures from lake sediments in order to elucidate whether the mineral assemblages found in the lake can be reproduced. Experiments using moderately halophilic bacteria obtained from the lake sediments demonstrate the formation of various calcium-/magnesium-carbonates: hydromagnesite, dypingite, huntite, monohydrocalcite and aragonite. The relative amounts of different mineral phases, particularly monohydrocalcite, hydromagnesite and dypingite, could be controlled by varying the sulphate concentration in the media from 0 to 56 mM. The similar mineral assemblages identified in the sediments of Lake Acigl and in the experiments point to similar thermodynamic conditions and kinetics of crystal growth. In particular, the similar spherical morphology points to a rapid crystal growth under strong kinetic inhibition, possibly by organic polymers that are commonly produced by microbial communities. Our results demonstrate that the authigenic carbonate paragenesis of hypersaline lakes as Lake Acigl can be reproduced in halophilic bacterial cultures. The exact thermodynamic conditions and precipitation kinetics under seasonally changing water chemistry or in batch experiment, however, still have to be constrained in order to establish a microbial model for carbonate precipitation in such environments.

Balci, Nurgul; Menekse, Meryem; Gl Karagler, Nevin; Seref Snmez, M.; Meister, Patrick

2014-05-01

321

Recovery of an offshore lake trout (Salvelinus namaycush) population in eastern Lake Superior  

USGS Publications Warehouse

The lake trout (Salvelinus namaucush) population at Stannard Rock, Michigan, an isolated offshore reef in eastern Lake Superior, was monitored each spring from 1959-79 using a permit assessment gill net fishery. This population, like nearly all of those in inshore waters, declined to low levels during the years of intense predation by the sea lamprey (Petromyzon marinus) in the late 1950's and early 1960's. After sea lamprey control began in 1961, the abundance of native lake trout at Stannard Rock began to increase slowly in the 1960's and was limited to recruitment into the fishable stock of native fish that were juveniles during the years of high sea lamprey activity. By the early 1970's lake trout abundance increased sharply and remained at a high level. This rapid recovery resulted from several strong year classes produced by the small spawning aggregations that reached maturity in the 1960's. Reproduction occurred in all years during and after the peak of sea lamprey activity in 1959. The strengths of year classes produced in 1963-1968 were related to the relative abundance of spawners the previous fall.

Curtis, Gary L.

1990-01-01

322

A coupled lake-atmosphere model (CLAM) and its application to Lake Kinneret  

Microsoft Academic Search

Kinneret is a 166-km2 lake located in Northern Israel, in the central part of the Jordan Valley, a corridor running from north to south, between the Galilee hills in the west and the Golan Heights in the east. Both the Galilee hills and the Golan Heights reach an elevation of about 400 m above mean sea level (MSL), and the

Hai Pan

1999-01-01

323

Sea urchin  

NSDL National Science Digital Library

The sea urchin is a type of echinoderm. It is a consumer because it cannot make its own food and must eat other organisms to get energy. Sea urchins are omnivores, meaning they eat both plants and other animals to gain energy. Sea urchins have been known to eat algae, mussels, and sponges.

N/A N/A (NOAA;Channel Islands National Marine Sanctuary)

2004-12-23

324

Sensitivity of the East African rift lakes to climate variability  

NASA Astrophysics Data System (ADS)

Lakes in the East African Rift have provided excellent proxies to reconstruct past climate changes in the low latitudes. The lakes occupy volcano-tectonic depressions with highly variable climate and hydrological setting, that present a good opportunity to study the climatic and hydrogeological influences on the lake water budget. Previous studies have used lake floor sediments to establish the sensitivity of the East African rift lakes. This study focuses on geomorphology and climate to offer additional or alternative record of lake history that are key to quantifying sensitivity of these lakes as archives to external and internal climatic forcings. By using the published Holocene lake areas and levels, we analyze twelve lakes on the eastern arm of the East African rift; Ziway, Awassa, Turkana, Suguta, Baringo, Nakuru, Elmenteita, Naivasha, Natron, Manyara and compare with Lake Victoria, that occupies the plateau between the east and the western arms of the rift. Using the SRTM data, Hypsometric (area-altitude) analysis has been used to compare the lake basins between latitude 80 North and 30 South. The mean elevation for the lakes, is between 524 and 2262 meters above sea level, the lakes' hypsometric integrals (HI), a measure of landmass volume above the reference plane, vary from 0.31 to 0.76. The aridity index (Ai), defined as Precipitation/ Evapotranspiration, quantifies the water available to a lake, it encompasses land cover and climatic effects. It is lowest (arid) in the basin between the Ethiopian rift and the Kenyan rift and at the southern termination of the Kenyan Rift in the catchments of lake Turkana, Suguta, Baringo and Manyara with values of 0.55, 0.43, 0.43 and 0.5 respectively. And it is highest (wet) in the catchments of, Ziway, Awassa, Nakuru and Naivasha as 1.33,1.03 and 1.2 respectively, which occupy the highest points of the rift. Lake Victoria has an index of 1.42 the highest of these lakes and receives a high precipitation. We use a simple model written on a Matlab code to illustrate the lake volume and area response to climate of surficialy closed, graben shaped and panshaped lake basins. From preliminary results, lake basins that are sensitive to climate variability have a high HI and high aridity index, which will be presented in this conference

Olaka, L.; Trauth, M. H.

2009-04-01

325

Population dynamics of Lake Ontario lake trout during 1985-2007  

USGS Publications Warehouse

Lake trout Salvelinus namaycush were extirpated from Lake Ontario circa 1950 owing to commercial and recreational fishing, predation by sea lampreys Petromyzon marinus, and habitat degradation. Since the 1970s, substantial efforts have been devoted to reestablishing a self-sustaining population through stocking, sea lamprey control, and harvest reduction. Although a stocking-supported population has been established, only limited natural reproduction has been detected. Since the 1990s, surveys have indicated a continuing decline in overall abundance despite fairly static stocking levels. We constructed a statistical catch-at-age model to describe the dynamics of Lake Ontario lake trout from 1985 to 2007 and explore what factor(s) could be causing the declines in abundance. Model estimates indicated that abundance had declined by approximately 76% since 1985. The factor that appeared most responsible for this was an increase in age-1 natural mortality rates from approximately 0.9 to 2.5 between 1985 and 2002. The largest source of mortality for age-2 and older fish was sea lamprey predation, followed by natural and recreational fishing mortality. Exploitation was low, harvest levels being uncertain and categorized by length rather than age. Accurate predictions of fishery harvest and survey catch per unit effort were obtained despite low harvest levels by using atypical data (e.g., numbers stocked as an absolute measure of recruitment) and a flexible modeling approach. Flexible approaches such as this might allow similar assessments for a wide range of lightly exploited stocks. The mechanisms responsible for declining age-1 lake trout survival are unknown, but the declines were coincident with an increase in the proportion of stocked fish that were of the Seneca strain and a decrease in the overall stocking rate. It is possible that earlier studies suggesting that Seneca strain lake trout would be successful in Lake Ontario are no longer applicable given the large ecosystem changes that have occurred subsequent to invasion by dreissenid mussels.

Brenden, Travis O.; Bence, James R.; Lantry, Brian F.; Lantry, Jana R.; Schaner, Ted

2011-01-01

326

Holocene Lake Records on Kamchatka  

NASA Astrophysics Data System (ADS)

The availibility of terrestrial records of Holocene palaeoenvironmental changes in eastern Siberia still is quite limited, compared to other regions on the northern hemisphere. In particular, the Kamchatka Peninsula as an important climate-sensitive region is very underrepresented. Situated at the border of northeastern Eurasia, the maritime-influenced terrestrial setting of Kamchatka offers the potential to pinpoint connections of environmental changes between the periglacial and highly continental landmasses of eastern Siberia and the sub-Arctic Pacific Ocean and Sea of Okhotsk. The study region lies at the eastern end-loop of the global thermohaline ocean conveyor belt and is strongly affected by atmospheric teleconnections. Volcanic, tectonic, and glacial processes overprint palaeoenvironmental changes in addition to primary climate forcing. In order to widen our understanding of plaeoclimate dynamics on Kamchatka, sediment cores from different lake systems and peat sections were recovered and analysed by a multi-proxy approach, using sedimentological and geochemical data as well as fossil bioindicators, such as diatoms, pollen, and chironomids. Chronostratigraphy of the studied records was achieved through radiocarbon dating and tephrostratigraphy. Sediment cores with complete Holocene sedimentary sequences were retrieved from Lake Sokoch, an up to six metre deep lake of proglacial origin, situated at the treeline in the Ganalsky Ridge of southern central Kamchatka (5315,13'N, 15745.49' E, 495 m a.s.l.). Lacustrine sediment records of mid- to late Holocene age were also recovered from the up to 30 m deep Two-Yurts Lake, which occupies a former proglacial basin at the eastern flank of the Central Kamchatka Mountain Chain, the Sredinny Ridge (5649.6'N, 16006.9'E, 275 m a.s.l.). In addition to sediment coring in the open and deep Two-Yurts Lake, sediment records were also recovered from peat sections and small isolated forest lakes to compare palaeoecologocal responses in different lake systems under same climatic boundary conditions. Our findings give evidence of longterm climate changes that suggest the existence of a warm and humid early Holocene climate optimum between roughly 9.0 and 4.5 ka BP, followed by climate deterioration of the neoglacial epoch in concert with summer cooling, glacial advances, and enhanced continentality. Two strong cooling episodes punctuated late Holocene climate development between 4.5 and 3.5 ka BP and during the last millennium, marking the prelude of neoglacial cooling and the Little Ice Age. This general development of Holocene climate on Kamchatka is in line with environmental changes in the neighbouring Sea of Okhotsk, where the pattern of sea-ice dynamics is consistent with early Holocene warmth and Neoglacial climate cooling. While the marine records from the Sea of Okhotsk mainly reflect winter conditions, our findings show that summer climate on Kamchatka shows a similar trend of temporal change. Holocene climate variability on Kamchatka was mainly driven by external insolation forcing, changes in solar activity, and internal climate forcing. The latter is dictated by by the relative position of the Aleutan Low in response to the prevailing modes of Pacific Decadal Oscillation and the Arctic Oscillation that both control the influence of maritime or continental air masses and the intensity of rain- or snow-bringing cyclones.

Diekmann, Bernhard; Biskaborn, Boris; Chapligin, Bernhard; Dirksen, Oleg; Dirksen, Veronika; Hoff, Ulrike; Meyer, Hanno; Nazarova, Larisa

2014-05-01

327

Great Lakes RESTORATION  

E-print Network

, lengthen periods of lake stratification, and elevate the risk of hypoxia and algal blooms. RestoringGreat Lakes RESTORATION NATIONALOCEAN IC AND ATMOSPHERIC ADMINISTRATION U.S. D EPARTMENT OF COMM E R CE Great Lakes Restoration Initiative Recognizing the importance of the Great Lakes to our nation

328

Great Lakes RESTORATION  

E-print Network

Great Lakes RESTORATION NATIONALOCEAN IC AND ATMOSPHERIC ADMINISTRATION U.S. D EPARTMENT OF COMM E R CE Great Lakes Restoration Initiative Recognizing the importance of the Great Lakes to our nation, President Obama made restoration a national priority. The resulting Great Lakes Restoration Initiative (GLRI

329

Great Lakes RESTORATION  

E-print Network

Great Lakes RESTORATION NATIONALOCEAN IC AND ATMOSPHERIC ADMINISTRATION U.S. D EPARTMENT OF COMM E R CE The Great Lakes Restoration Initiative Recognizing the importance of the Great Lakes to our nation, President Obama made their restoration a national priority. The resulting Great Lakes Restoration

330

Connection between Caspian Sea level variability and ENSO  

Microsoft Academic Search

The problem of the world greatest lake, the Caspian Sea level, changes attracts the increased attention due to its environmental consequences and unique natural characteristics. Despite the huge number of studies aimed to explain the reasons of the sea level variations the underlying mechanism has not yet been clarified. The important question is to what extent the CSL variability is

K. Arpe; L. Bengtsson; G. S. Golitsyn; I. I. Mokhov; V. A. Semenov; P. V. Sporyshev

2000-01-01

331

Dramatic Evaporation of the Aral Sea  

NSDL National Science Digital Library

DISAPPEARING WATER: THE ARAL SEA OVER TIME, FROM 1973 TO 2001 A time series is a powerful illustrative tool. Where in the case of Las Vegas we see the direct effects of people on the land, in the case of the Aral Sea, separating the countries of Kazakhstan and Uzbekistan, we see indirect, but no less dramatic effects on a different part of the world. The Aral Sea is actually not a sea at all. It is an immense lake, a body of fresh water, although that particular description of its contents might now be more a figure of speech than practical fact. In the last thirty years, more than sixty percent of the lake has disappeared. As youll see in the visualization, the change over time is dramatic. In the 1970s, farmers and state offices opened significant diversions from the rivers supplying water to the lake, sending millions of gallons to irrigate cotton fields and rice paddies. So voluminous were these irrigation sluices that concentrations of salts and minerals began to rise in the shrinking body of water. That change in chemistry has led to staggering alterations in the lakes ecology, causing precipitous drops in the Arals fish population. A secondary effect of this reduction in the Aral Seas overall size is the rapid exposure of the lake bed. Powerful winds that blow across this part of Asia routinely pick up and deposit tens of thousands of tons of now exposed soil every year. This has not only contributed to significant reduction in breathable air quality for nearby residents, but also appreciably affected crop yields due to those heavily salt laden particles falling on arable land. In the following sequence of images, we see a series of Landsat scenes taken several years apart. As the years pass, we see the profound reduction in overall area covered by the Aral, and a commensurate increase in land area as the floor of the sea now lies exposed.

Thomson, Joycelyn; Williams, Darrel

2001-04-19

332

Changes in the diet of lake trout (Salvelinus namaycush) in near-shore Lake Michigan with the invasion of the Round Goby (Neogobius melanostomus): 1995-2005  

Microsoft Academic Search

The predator-prey base of the Great Lakes has been altered since the early 1900's, with the majority of these changes occurring due to invasive species such as the sea lamprey (Petromyzon marin us), alewife (A los a pseudoharangus ), and rainbow smelt (Osmerus mordax). These changes have forced large piscivorous fish to find alternate prey species. One predator, the lake

Marybeth K. Brey

2006-01-01

333

Fleet dynamics of the commercial lake trout fishery in Michigan waters of Lake Superior during 1929-1961  

USGS Publications Warehouse

Understanding fishing fleet dynamics is important when using fishery dependent data to infer the status of fish stocks. We analyzed data from mandatory catch reports from the commercial lake trout (Salvelinus namaycush) fishery in Michigan waters of Lake Superior during 1929-1961, a period when lake trout populations collapsed through the combined effects of overfishing and sea lamprey (Petromyzon marinus) predation. The number of full-time fishermen increased during 1933-1943 and then decreased during 1943-1957. Addition of new fishermen was related to past yield, market prices, World War II draft exemptions, and lost fishing opportunities in Lake Huron and Lake Michigan. Loss of existing fishermen was related to declining lake trout density. Large mesh (a?Y 114-mm stretch-measure) gill net effort increased during 1929-1951 because fishermen fished more net inshore as lake trout density declined, even though catch per effort (CPE) was often higher in deeper waters. The most common gill net mesh size increased from 114-mm to 120-mm stretch-measure during 1929-1957, as lake trout growth increased. More effort was fished inshore than offshore and the amount of inshore effort was less variable over time than offshore effort. Relatively stable yield was maintained by increasing gill net effort and by moving some effort to better grounds. Because fishing-up caused yield and CPE to remain high despite declining lake trout abundance, caution must be used when basing goals for lake trout restoration on historical fishery indices.

Wilberg, Michael J.; Bronte, Charles R.; Hansen, Michael J.

2004-01-01

334

Population biology of lake trout (Salvelinus namaycush) of Lake Superior before 1950  

USGS Publications Warehouse

Scale samples collected in 1948 were used to estimate the instantaneous total mortality rate (0.70) and growth for lake trout (Salvelinus namaycush) in Lake Superior before the population had been significantly reduced by the sea lamprey (Petromyzon marinus). Indirect evidence indicates that the instantaneous natural mortality rate was probably 0.10-0.25. The Ricker model was used to calculate yield per recruitment, which varied with natural mortality and growth. Natural mortality was more critical than growth; yield per recruitment increased 183.3% with a 60% decrease in instantaneous natural mortality (from 0.25 to 0.10). For the prelamprey lake trout population the yield per recruitment was about 12-34 lb; the recruitment of about 3.6-10.1 million lake trout of age 1.5 resulted in an annual commercial production of 4 million lb.

Sakagawa, Gary T.; Pycha, Richard L.

1971-01-01

335

Longevity of Lake Superior lake trout  

USGS Publications Warehouse

The age structure of mature lake trout Salvelinus namaycush from the Wisconsin waters of Lake Superior increased following a population recovery that has taken place since the 1960s. As the population aged, it became apparent that scales were unreliable aging structures. Beginning in 1986, we examined both scale and sagittal otolith ages from tagged fish with a known period at liberty. We found large discrepancies in scale and sagittal otolith ages of mature fish, such that scale ages were biased low. We estimated lake trout living up to 42 years, which is greater than previously reported from Lake Superior. Investigators studying lake trout population dynamics in the Great Lakes should be aware that lake trout can live longer than previously thought.

Schram, Stephen T.; Fabrizio, Mary C.

1998-01-01

336

Late Glacial-Holocene palaeoceanography of the Sea of Marmara: timing of connections with the Mediterranean and the Black Seas  

Microsoft Academic Search

Stratigraphic analysis of Late Quaternary sediments of the Sea of Marmara Basin (SMB) indicates that it was a freshwater lake during the late glacial to ca 12,000 yr BP, depositing sediments with a Neoeuxinian fauna characteristic of the Black Sea Basin. At ca 12,000 yr BP, it was inundated by the Mediterranean waters and gradually converted into a marine realm

N. Gorur; O. Alganb; C. Eastoe; A. Tchapalyga; D. Onganb; T. Kuhne; I. Kuscu

2000-01-01

337

International Lake Environment Committee  

NSDL National Science Digital Library

The International Lake Environment Committee (ILEC) works to advance international cooperation for sustainable management of the world's lakes and reservoirs through the collection and provision of environmental data, the promotion of scientific research, and the promotion of interchange with government agencies and research institutes. The World Lake Database is particularly interesting and gives the user the ability to navigate to lakes around the world providing facts about each lake.

2008-11-18

338

29 CFR 784.130 - At sea.  

...at sea to include only bodies of water subject to the ebb and flow of the tides or to saline waters would exclude the Great Lakes which obviously would not comport with the legislative intent. On the other hand, one performing the named...

2014-07-01

339

MODELING SALINITY BALANCE IN PROPOSED SALTON SEA RESTORATION USING A DIKED IMPOUNDMENT  

E-print Network

MODELING SALINITY BALANCE IN PROPOSED SALTON SEA RESTORATION USING A DIKED IMPOUNDMENT Victor M: A proposal for the restoration of the Salton Sea, in California, consists of the separation of the lake the restoration period. Modeling shows that if water deliveries to the Salton Sea continue at recent historic

Ponce, V. Miguel

340

Automatic Temporal Tracking of Supra-Glacial Lakes  

NASA Astrophysics Data System (ADS)

During the recent years, supra-glacial lakes in Greenland have attracted extensive global attention as they potentially play an important role in glacier movement, sea level rise, and climate change. Previous works focused on classification methods and individual cloud-free satellite images, which have limited capabilities in terms of tracking changes of lakes over time. The challenges of tracking supra-glacial lakes automatically include (1) massive amount of satellite images with diverse qualities and frequent cloud coverage, and (2) diversity and dynamics of large number of supra-glacial lakes on the Greenland ice sheet. In this study, we develop an innovative method to automatically track supra-glacial lakes temporally using the Moderate Resolution Imaging Spectroradiometer (MODIS) time-series data. The method works for both cloudy and cloud-free data and is unsupervised, i.e., no manual identification is required. After selecting the highest-quality image within each time interval, our method automatically detects supra-glacial lakes in individual images, using adaptive thresholding to handle diverse image qualities. We then track lakes across time series of images as lakes appear, change in size, and disappear. Using multi-year MODIS data during melting season, we demonstrate that this new method can detect and track supra-glacial lakes in both space and time with 95% accuracy. Attached figure shows an example of the current result. Detailed analysis of the temporal variation of detected lakes will be presented. (a) One of our experimental data. The Investigated region is centered at Jakobshavn Isbrae glacier in west Greenland. (b) Enlarged view of part of ice sheet. It is partially cloudy and with supra-glacial lakes on it. Lakes are shown as dark spots. (c) Current result. Red spots are detected lakes.

Liang, Y.; Lv, Q.; Gallaher, D. W.; Fanning, D.

2010-12-01

341

Status report - Salton Sea solar pond power plant  

SciTech Connect

The feasibility of constructing salt gradient solar pond commercial power plants in the Salton Sea has been confirmed by a study completed in May 1981. The Salton Sea is an inland salt lake located in the Imperial Valley of Southern California. 600 MW/sub e/ of base load power can be generated if 15% of the sea's 932-km/sup 2/ (360-square mile) surface area is converted to solar ponds. 3 refs.

French, R.L.; Lin, E.I.H.

1981-01-01

342

Buried paleo-channel system and records of sea level changes on the continental shelf in Yingge Sea Basin  

Microsoft Academic Search

High resolution geophysical instruments were used to locate many buried paleo-channels, paleo-lakes, and river mouth paleo-deltas\\u000a formed during low sea level at the end of Late Pleistocene and Early Holocene. Some paleo-rivers flowed southward into the\\u000a paleo-lake and others southeastward into the Paleo-South China Sea. It may be inferred from data on buried paleo-channels\\u000a that sea level remained for some

Fan Li; Jiezao Zhuang; Jianjun Yu; Quansheng Du; Tailu Dong; Xiuhang Jiang

1990-01-01

343

Using Real-World Data to Examine Climate Change Implications for Lake Superior  

NSDL National Science Digital Library

This activity was developed during the workshop, Teaching Climate Change: Insight from Large Lakes, held in June 2012.by Diane Desotelle, MN Sea GrantKevin Theissen, University of St. ThomasTopic: Climate change ...

344

NAME: Grassy Flats Estuarine Habitat Restoration Project LOCATION: Lake Worth Lagoon, Florida, USA  

E-print Network

by maximizing carbon sequestration and allowing for a natural succession of habitat types as sea level risesNAME: Grassy Flats Estuarine Habitat Restoration Project LOCATION: Lake Worth Lagoon, Florida, USA

US Army Corps of Engineers

345

Sustaining our nation's ocean, coastal and Great Lakes resources through university-based  

E-print Network

the goals set forth in this plan. The Sea Grant programs will strive to achieve these national goals in a manner that reflects the particular needs of the nation's ocean, coastal and Great Lakes resources through informed personal, policy

346

[Decompression problems in diving in mountain lakes].  

PubMed

The relationship between tolerated high-pressure tissue nitrogen and ambient pressure is practically linear. The tolerated nitrogen high pressure decreases at altitude, as the ambient pressure is lower. Additionally, tissues with short nitrogen half-times have a higher tolerance than tissues which retain nitrogen for longer duration. For the purpose of determining safe decompression routines, the human body can be regarded as consisting of 16 compartments with half-times from 4 to 635 minutes for nitrogen. The coefficients for calculation of the tolerated nitrogen-high pressure in the tissues can be deduced directly from the half-times for nitrogen. We show as application the results of 573 simulated air dives in the pressure-chamber and 544 real dives in mountain lakes in Switzerland (1400-2600 m above sea level) and in Lake Titicaca (3800 m above sea level). They are in accordance with the computed limits of tolerance. PMID:2799365

Bhlmann, A A

1989-08-01

347

Dead Sea rhodopsins revisited.  

PubMed

The Dead Sea is a unique hypersaline ecosystem with near toxic magnesium levels (?2?M), dominance of divalent cations and a slightly acidic pH. Previously, we reported a haloarchaeon related to Halobacterium salinarum to dominate in a microbial bloom that developed in 1992 in the upper water layers of the lake following massive freshwater runoff. Whether this clade also dominated an earlier bloom in 1980-1982 cannot be ascertained as no samples for cultivation-independent analysis were preserved. The presence of the light-driven proton pump bacteriorhodopsin was reported in the 1980-1982 bloom of prokaryotes that had developed in the Dead Sea. To test the hypothesis that bacteriorhodopsin proton pumping may play a major role in determining what type of haloarchaea may dominate in specific bloom conditions, we compared rhodopsin genes recovered from Dead Sea biomass collected in different periods with genes coding for retinal proteins in isolated haloarchaea. Novel bacteriorhodopsin and sensory rhodopsin genes were found in samples collected in 2007 and 2010. The fact that no rhodopsin genes were recovered from samples collected during the 1992 bloom, which was dominated by a single species, suggests that different clades were present in the 1980-1982 and 1992 blooms, and that bacteriorhodopsin proton pumping did not necessarily play a determinative role in the dominance of specific halophiles in the blooms. PMID:23760932

Bodaker, Idan; Suzuki, Marcelino T; Oren, Aharon; Bj, Oded

2012-12-01

348

Sea Chest  

NSDL National Science Digital Library

By exploring life at sea for sailors and passengers, the Maritime Museum of San Diego offers insight into the history of maritime exploration, emigration, and commerce. Background and classroom activities are applicable to history, geography, social studies, science, art and other subjects. Emphasis on 19th Century sea travel and sailing ships, with topics including navigation techniques and technology, sailor's crafts, health and medicine at sea, shipboard life and social interactions.

349

Sea Stars  

NSDL National Science Digital Library

At first glance, starfish, more properly called sea stars, arent doing much of anything. In this video, Jonathans investigations reveal a slow-motion predator that hunts and attacks its prey. Traveling the world, Jonathan investigates sea stars from the tropics to the Antarctic and uses time-lapse photography to reveal an amazing complexity to the world of the sea star. Please see the accompanying study guide for educational objectives and discussion points.

Productions, Jonathan B.

2010-10-06

350

Warming Drops Great Lakes to Historic Lows  

NSDL National Science Digital Library

As part of this lesson plan, students will be asked to read a news article and to construct and explain theories for the decline of the water level of the Great Lakes. They should be able to locate the Great Lakes on a map, compare them to lakes in other parts of the world, hypothesize what might happen in the short term if global temperatures continue to rise, and to consider these seemingly contradictory events: water is evaporating and levels are declining in some places in the world, while polar melting is causing sea levels to rise. Students form groups and develop a theory, supported by at least three pieces of evidence, to explain the water level decline and present their theories to the class.

2000-04-27

351

Fish community change in Lake Superior, 1970-2000  

USGS Publications Warehouse

Changes in Lake Superior's fish community are reviewed from 1970 to 2000. Lake trout (Salvelinus namaycush) and lake whitefish (Coregonus clupeaformis) stocks have increased substantially and may be approaching ancestral states. Lake herring (Coregonus artedi) have also recovered, but under sporadic recruitment. Contaminant levels have declined and are in equilibrium with inputs, but toxaphene levels are higher than in all other Great Lakes. Sea lamprey (Petromyzon marinus) control, harvest limits, and stocking fostered recoveries of lake trout and allowed establishment of small nonnative salmonine populations. Natural reproduction supports most salmonine populations, therefore further stocking is not required. Nonnative salmonines will likely remain minor components of the fish community. Forage biomass has shifted from exotic rainbow smelt (Osmerus mordax) to native species, and high predation may prevent their recovery. Introductions of exotics have increased and threaten the recovering fish community. Agencies have little influence on the abundance of forage fish or the major predator, siscowet lake trout, and must now focus on habitat protection and enhancement in nearshore areas and prevent additional species introductions to further restoration. Persistence of Lake Superior's native deepwater species is in contrast to other Great Lakes where restoration will be difficult in the absence of these ecologically important fishes.

Bronte, Charles R.; Ebener, Mark P.; Schreiner, Donald R.; DeVault, David S.; Petzold, Michael M.; Jensen, Douglas A.; Richards, Carl; Lozano, Steven J.

2003-01-01

352

Where was the outlet of the ice-dammed Lake Komi, Northern Russia?  

Microsoft Academic Search

When ice-sheets on the continental shelves of the Barents and Kara seas expanded onto the Russian mainland, north-flowing rivers were blocked. The last proglacial lake in European Russia dammed between the ice-sheet in the north and the drainage divide in the south was Lake Komi, which has been dated to the Early Weichselian, 80100 ka. The lake was about 1400

Olga Maslenikova; Jan Mangerud

2001-01-01

353

Effects of Acid Precipitation on a Small Acid Lake in Southern Norway  

Microsoft Academic Search

Langtjern is an acid lake situated in south-central Norway, 516 m above sea level. The watershed is underlain by biotite gneisses and granites. Coniferous forests cover 63% of the watershed, while 16% is covered by peaty areas. The lake has a relatively large watershed (4.8 km2) in relation to lake size (0.23 kmz), and most of the water and chemicals

Arne Henriksen; Richard F. Wright

1977-01-01

354

Acidification and other chemical changes in Halifax County lakes after 21 years  

Microsoft Academic Search

Sixteen of 23 lakes sampled in 1955 show no sign of significant physical alterations within their drainage basins over a 21-year interval, so that chemical changes in these lakes can be assumed to reflect changes in atmospheric inputs. In all 16, the pH levels have declined, with greater declines in the higher pH (near neutrality) lakes. After correction for sea-salt

W. D. Watt; D. Scott; S. Ray

1979-01-01

355

Lake Trout Movements in Northwestern Lake Michigan  

Microsoft Academic Search

We quantified the distance that lake troutSalvelinus namaycushmoved in northwestern Lake Michigan and examined (1) the directional preference and (2) the effect of population density on movement. Lake trout were captured in spring and fall 1983-1996, tagged with Floy anchor tags, and recaptured during subsequent agency sampling and by commercial fishers and anglers during 1983-1997. Angler recaptures were used to

Patrick J. Schmalz; Michael J. Hansen; Mark E. Holey; Patrick C. McKee; Michael L. Toneys

2002-01-01

356

Investigation of the self-cleaning ability of Lake Koumoundourou near Athens from oil pollution  

Microsoft Academic Search

This study was performed under a general project for the restoration of Lake Koumoudourou. This lake is situated next to the sea in the prefecture of Attica, with a large oil refinery installation and a military fuel depot nearby. The geological formations of the surrounding area are quaternary alluvial deposits and fans, which overlie karstic limestone and dolomites of the

S. Koutsomitros; T. Mimides; A. Sgoumpopoulou; S. Rizos

2001-01-01

357

U.S. Federal Research on Fisheries and Limnology in the Great Lakes through  

E-print Network

528 U.S. Federal Research on Fisheries and Limnology in the Great Lakes through 1964: An Annotated, Donald L. McKernan, Director U.S. Federal Research on Fisheries and Limnology in the Great Lakes through The research program, 1957-64 1 Sea lamprey 1 Fisheries and limnology 4 Publications by staff members 5

358

The characteristic of the Younger Dryas Event in Bilut Lake, Inner Mongolia, China  

Microsoft Academic Search

To investigate the region which affected by Younger Dryas Event, we collect sediments of the lakes from Inner Mongolia of China. In general, sediments of lakes and sea are considered as a good material to study climate change because they could record continuously the information about the change of environment for long time. Inner Mongolia is located at the central

H. Hsiao; S. Song; H. Chen; Y. Wang; T. Lee

2010-01-01

359

Transport and Mixing Between the Coastal and Offshore Waters in the Great Lakes: a Review  

Microsoft Academic Search

The Laurentian Great Lakes of North America have horizontal scales of hundreds of kilometers and depth scales of hundreds of meters. In terms of coastal dynamics, they behave much like inland seas and exhibit physical processes characteristic of the coastal oceans. The lakes are dynamically similar to the coastal ocean in that their horizontal dimensions are larger than the vertical

Yerubandi R. Rao; David J. Schwab

2007-01-01

360

Stable isotopic records of lake sediments from Taal Lake in central Philippines during the past 60 years  

NASA Astrophysics Data System (ADS)

Taal Lake is located in Batangas Province of central Philippines (140.01'N, 120 59.1'E), with a surface area of 267 km2, a maximum depth of 176 m and an elevation of 3 m above sea level. The lake occupies the famous Taal Volcano system which consists of a 15?22-km prehistoric caldera. The 5-km-wide Taal Volcano Island which has 47 craters and 4 maars, lies in the north-central Taal Lake. With 34 recorded eruptions, Taal Volcano is one of the 16 monitored volcanoes by the Global Volcanism Network. A 120-cm long gravity core was retrieved from 15-m water depth of Taal volcanic lake located in the central Philippines. Dated by the nuclear bomb introduced-14C curve, the core reveals a detailed sedimentary history of Taal Lake during the past 60 years. ?18O and ?13C analyses on bulk carbonates and ?13C measurements on organic carbon in the sediments were carried out for 56 samples. The annual resolution ?18O and ?13C records provide us the detailed variations of the lake's hydrological, biological and sedimentary history. Carbonate was precipitated in isotopic equilibrium with the lake water at ~30oC which is close to the measured water temperature. The ?18O and ?13C of the carbonates co-vary in the core, exhibiting the feature of a closed lake. In general, when there is more input surface water, the ?18O and ?13C of the lake goes lighter due to dilution effect. The lake productivity at this time will be lower, and carbonate precipitation is less. When the lake experiences less surface water input and/or more evaporation, the ?18O and ?13C of the lake goes heavier due to the hydrological balance and increased lake productivity. However, when the volcanic activity increases, significant amount of hydrothermal input and deep CO2 input will lead to increase of lake's ?18O and ?13C. Both carbonate and organic carbon will decrease due to the influence of volcanic input. This situation was occurred around 1991. However, if a volcanic eruption causes significant amount of dead carbon from vegetation and organism in and around the lake, the lake's ?13C will be depleted. At the time, the ?18O and ?13C of the lake goes the opposite way. The 1965 eruption may be an example of such a case. With the detailed geochemical profiles, we are able to reconstruct climatic, environmental and volcanic history of Taal Lake area.

Li, H.-C.; Xu, X.-M.; Wan, N.-J.; Kuo, T.-S.; Campita, N.; Bautista, B. C.

2009-04-01

361

Sea Turtles  

NSDL National Science Digital Library

In Malaysia there is an island known for more sea turtles than virtually anywhere on Earth. In this video, Jonathan visits this amazing ecosystem to learn about the life cycle of sea turtles. He is surprised to discover an amazingly complex and competitive environment. Please see the accompanying study guide for educational objectives and discussion points.

Productions, Jonathan B.

2010-03-29

362

Utah: Salt Lake City  

... Snow-Covered Peaks of the Wasatch and Uinta Mountains View Larger Image ... Winter Olympics, to be held in Salt Lake City, Utah. The mountains surrounding Salt Lake City are renowned for the dry, powdery snow ...

2014-05-15

363

Lake Michigan Sand Waves  

USGS Multimedia Gallery

Calm Lake Michigan morning while sampling dead and dying fish for viral hemorrhagic septicemia virus (VHSV). This virus has recently emerged in the Great Lakes and caused severe epidemics in many fish species....

2009-12-11

364

Colonization and evolution of lakes on the central Norwegian coast following deglaciation and land uplift 9500 to 7800 years B.P  

Microsoft Academic Search

Invertebrate colonization of lakes following the uplift of land from the sea was studied in four lakes, currently situated between 39 and 24 m a.s.l., on the central Norwegian coast. The lakes were isolated from the sea between 9500 and 7700 years B.P. Animal and algal remains picked from core samples showed that the first colonizers preserved as fossils were

John O. Solem; Thyra Solem; Kaare Aagaard; Oddvar Hanssen

1997-01-01

365

Where was the outlet of the ice-dammed Lake Komi, Northern Russia?  

NASA Astrophysics Data System (ADS)

When ice-sheets on the continental shelves of the Barents and Kara seas expanded onto the Russian mainland, north-flowing rivers were blocked. The last proglacial lake in European Russia dammed between the ice-sheet in the north and the drainage divide in the south was Lake Komi, which has been dated to the Early Weichselian, 80-100 ka. The lake was about 1400 km long with a water level of about 100 m a.s.l. In the present paper, we discuss four alternative outlets: (1) Across the drainage divide towards the Volga River, leading the water southwards into the Caspian Sea; (2) across the Polar Urals towards West Siberia; (3) between the Barents Ice Sheet and the northern slope of the Kola Peninsula, leading the water northwestwards into the Norwegian Sea; and (4) across the drainage divide between the White Sea and the Baltic Sea catchment areas. Based on present knowledge, we consider the first three options unlikely. Across the divide to the Baltic Sea, a buried channel is mapped where the threshold altitude is lower than the Lake Komi level. We conclude that the outlet of Lake Komi probably followed this valley towards the Baltic Sea. However, the Scandinavian Ice Sheet overran this drainage divide during the Late Weichselian and therefore a younger till and other sediments cover the channel.

Maslenikova, Olga; Mangerud, Jan

2001-11-01

366

Great Minds? Great Lakes!  

ERIC Educational Resources Information Center

This book contains lesson plans that provide an integrated approach to incorporating Great Lakes environmental issues into elementary subjects. The book is divided into three subject areas: (1) History, which includes the origins of the Great Lakes, Great Lakes people, and shipwrecks; (2) Social Studies, which covers government, acid rain as a

Environmental Protection Agency, Chicago, IL. Great Lakes National Program Office.

367

Great Lakes: Chemical Monitoring  

ERIC Educational Resources Information Center

The Tenth Great Lakes Regional Meeting of the American Chemical Society met to assess current Chemical Research activity in the Great Lakes Basin, and addressed to the various aspects of the theme, Chemistry of the Great Lakes. Research areas reviewed included watershed studies, atmospheric and aquatic studies, and sediment studies. (BT)

Delfino, Joseph J.

1976-01-01

368

Lake Layers: Stratification.  

ERIC Educational Resources Information Center

This teacher guide and student workbook set contains two learning activities, designed for fifth through ninth grade students, that concentrate on lake stratification and water quality. In the activities students model the seasonal temperature changes that occur in temperate lakes and observe the resulting stratification of lake waters. Students

Brothers, Chris; And Others

369

A Killer Lake  

ERIC Educational Resources Information Center

In 1986, Lake Nyos, a volcanic lake in Cameroon, released a huge amount of carbon dioxide gas, killing over 1,700 people in the surrounding area. This case study, developed for use in a limnology or aquatic biology course, explores that event, introducing students to concepts relating to lake formation, thermal stratification, and dissolved gases.

Horvath, Thomas

2005-01-01

370

Great Lakes NATIONALOCEAN  

E-print Network

Great Lakes NATIONALOCEAN IC AND ATMOSPHERIC ADMINISTRATION U.S. D EPARTMENT OF COMM E R CE CoastWatch is a nationwide NOAA program in which the Great Lakes Environmental Research Laboratory (GLERL) functions as the Great Lakes regional node. GLERL obtains, produces, and delivers environmental data and products

371

LAKE COLUSA SAN JOAQUIN  

E-print Network

#S #S #S #S #S #S #S #S #S #S #S #S #S STANISLAUS ¡¢ 1 0 1 "!9 6 Lake Tahoe HUMBOLDT TEHAMA MENDOCINO DEL NORTE SISKIYOU MODOC LASSEN BUTTE PLUMAS GLENN LAKE COLUSA SUTTER YUBA NEVADA SIERRA PLACER EL Marysville Nevada City Downieville Auburn Coloma Placerville Soda Springs Tahoe Vista South Lake Tahoe

372

Microbial Diversity in Water and Sediment of Lake Chaka, an Athalassohaline Lake in Northwestern China  

PubMed Central

We employed culture-dependent and -independent techniques to study microbial diversity in Lake Chaka, a unique hypersaline lake (32.5% salinity) in northwest China. It is situated at 3,214 m above sea level in a dry climate. The average water depth is 2 to 3 cm. Halophilic isolates were obtained from the lake water, and halotolerant isolates were obtained from the shallow sediment. The isolates exhibited resistance to UV and gamma radiation. Microbial abundance in the sediments ranged from 108 cells/g at the water-sediment interface to 107 cells/g at a sediment depth of 42 cm. A major change in the bacterial community composition was observed across the interface. In the lake water, clone sequences affiliated with the Bacteroidetes were the most abundant, whereas in the sediments, sequences related to low G+C gram-positive bacteria were predominant. A similar change was also present in the archaeal community. While all archaeal clone sequences in the lake water belonged to the Halobacteriales, the majority of the sequences in the sediments were related to those previously obtained from methanogenic soils and sediments. The observed changes in the microbial community structure across the water-sediment interface were correlated with a decrease in salinity from the lake water (32.5%) to the sediments (approximately 4%). Across the interface, the redox state also changed from oxic to anoxic and may also have contributed to the observed shift in the microbial community. PMID:16751487

Jiang, Hongchen; Dong, Hailiang; Zhang, Gengxin; Yu, Bingsong; Chapman, Leah R.; Fields, Matthew W.

2006-01-01

373

Biogeochemistry of silica in Devils Lake: Implications for diatom preservation  

USGS Publications Warehouse

Diatom-salinity records from sediment cores have been used to construct climate records of saline-lake basins. In many cases, this has been done without thorough understanding of the preservation potential of the diatoms in the sediments through time. The purpose of this study was to determine the biogeochemistry of silica in Devils Lake and evaluate the potential effects of silica cycling on diatom preservation. During the period of record, 1867-1999, lake levels have fluctuated from 427 m above sea level in 1940 to 441.1 m above sea level in 1999. The biogeochemistry of silica in Devils Lake is dominated by internal cycling. During the early 1990s when lake levels were relatively high, about 94% of the biogenic silica (BSi) produced in Devils Lake was recycled in the water column before burial. About 42% of the BSi that was incorporated in bottom sediments was dissolved and diffused back into the lake, and the remaining 58% was buried. Therefore, the BSi accumulation rate was about 3% of the BSi assimilation rate. Generally, the results obtained from this study are similar to those obtained from studies of the biogeochemistry of silica in large oligotrophic lakes and the open ocean where most of the BSi produced is recycled in surface water. During the mid 1960s when lake levels were relatively low, BSi assimilation and water-column dissolution rates were much higher than when lake levels were high. The BSi assimilation rate was as much as three times higher during low lake levels. Even with the much higher BSi assimilation rate, the BSi accumulation rate was about three times lower because the BSi water-column dissolution rate was more than 99% of the BSi assimilation rate compared to 94% during high lake levels. Variations in the biogeochemistry of silica with lake level have important implications for paleolimnologic studies. Increased BSi water-column dissolution during decreasing lake levels may alter the diatom-salinity record by selectively removing the less resistant diatoms. Also, BSi accumulation may be proportional to the amount of silica input from tributary sources. Therefore, BSi accumulation chronologies from sediment cores may be effective records of tributary inflow.

Lent, R.M.; Lyons, B.

2001-01-01

374

Sea Level  

NSDL National Science Digital Library

This problem provides an opportunity to increase familiarity with negative and positive numbers on a number line. The vertical number line is presented as black markings every one meter all the way up a lighthouse and on the underwater support going down to the sea bed, with sea level being "0". In answering the nine questions, children begin to calculate with negative numbers in the context of the distances between the sea creatures. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for extension and support, and a link to a related resource, Swimming Pool (cataloged separately).

2008-01-01

375

Cytochrome P4501A expression, chemical contaminants and histopathology in roach, goby and sturgeon and chemical contaminants in sediments from the Caspian Sea, Lake Balkhash and the Ily River Delta, Kazakhstan  

Microsoft Academic Search

Roach, goby and sturgeon were examined for cytochrome P4501A (CYP1A) expression and histopathology, in relation to contaminant burdens in fish and sediment. Gradients of induction of CYP1A were observed. Roach from the Ural and Ily River Deltas and roach and goby from the two stations nearest the Caspian Sea oil fields displayed higher levels of CYP1A expression in several organs

Michael J. Moore; Igor V. Mitrofanov; Stefanie S. Valentini; Vjacheslav V. Volkov; Aleksey V. Kurbskiy; Elena N. Zhimbey; Lorraine B. Eglinton; John J. Stegeman

2003-01-01

376

High abundances of aerobic anoxygenic phototrophs in saline steppe lakes.  

PubMed

We studied the distribution of anoxygenic phototrophs in 23 steppe lakes in the Transbaikal region (Russia), in Uzbekistan (Central Asia) and in the Crimean peninsula (Ukraine). The lakes varied in their mineral content and composition (salinities from 0.2 to 300 g L(-1) ). The Transbaikal lakes were alkaline (pH>9), with high amounts of soda. The Uzbek and Crimean lakes were more pH neutral, frequently with high amounts of sulfates. The presence of anoxygenic phototrophs was registered by infrared epifluorescence microscopy, infrared fluorometry and pigment analyses. In mostly shallow, fully oxic lakes, the anoxygenic phototrophs represented 7-65% of the total prokaryotes, with the maxima observed in Transbaikal soda lakes Gorbunka (32%), Khilganta (65%), Zanday (58%) and Zun-Kholvo (46%). Some of the lakes contained over 1 ?g bacteriochlorophyll L(-1) . In contrast, only small amounts of anoxygenic phototrophs were present in highly mineralized lakes (>100 g total salts L(-1) ); Borzinskoe, Tsagan-Nur (Transbaikal), Staroe (Crimea) and in the residual part of the south-west Aral Sea (Uzbekistan). The oxic environment and the specific diurnal changes of bacteriochlorophyll concentration observed suggest that the phototrophic community was mostly composed of aerobic anoxygenic phototrophs. The high abundances and bacteriochlorophyll concentrations point to an important role of aerobic anoxygenic phototrophs in the habitats studied. PMID:21265869

Medov, Hana; Boldareva, Ekaterina N; Hrouzek, Pavel; Borzenko, Svetlana V; Namsaraev, Zorigto B; Gorlenko, Vladimir M; Namsaraev, Bair B; Koblek, Michal

2011-05-01

377

Partitioning potential fish yields from the Great Lakes  

USGS Publications Warehouse

We proposed and implemented procedures for partitioning future fish yields from the Great Lakes into taxonomic components. These projections are intended as guidelines for Great Lakes resource managers and scientists. Attainment of projected yields depends on restoration of stable fish communities containing some large piscivores that will use prey efficiently, continuation of control of the sea lamprey (Petromyzon marinus), and restoration of high-quality fish habitat. Because Great Lakes fish communities were harmonic before their collapse, we used their historic yield properties as part of the basis for projecting potential yields of rehabilitated communities. This use is qualified, however, because of possible inaccuracies in the wholly commercial yield data, the presence now of greatly expanded sport fisheries that affect yield composition and magnitude, and some possibly irreversible changes since the 1950s in the various fish communities themselves. We predict that total yields from Lakes Superior, Huron, and Ontario will be increased through rehabilitation, while those from Lakes Michigan and Erie will decline. Salmonines and coregonines will dominate future yields from the upper lakes. The Lake Erie fishery will continue to yield mostly rainbow smelt (Osmerus mordax), but the relative importance of percids, especially of walleye (Stizostedion vitreum vitreum) will increase. In Lake Ontario, yields of salmonines will be increased. Managers will have to apply the most rigorous management strictures to major predator species.

Loftus, D.H.; Olver, C.H.; Brown, Edward H.; Colby, P.J.; Hartman, Wilbur L.; Schupp, D.H.

1987-01-01

378

Mono Lake Web Site  

NSDL National Science Digital Library

Mono Lake Web Site is the homepage of the Mono Lake Committee and offers helpful information regarding the unique hypersaline and alkaline environment. Visitors will find information about the Mono Lake Committee, natural and political histories of the area, related water policies, a photo gallery with image descriptions, and links to related sites- including a clearinghouse. Those interested in Mono Basin birds will find sightings, counts, bird walks, and other related information. An additional feature, Mono Lake Live, offers up-to-the-minute data on road conditions, satellite images, weather, lake level, bird sightings, snow pack, and earthquakes.

Reis, Greg; Committee, Mono L.

379

Role of physical barriers in the control of sea lamprey (Petromyzon marinus)  

USGS Publications Warehouse

Mechanical and electromechanical barriers played a significant role in the initial attempts to control sea lamprey (Petromyzon marinus) populations in the upper Great Lakes. More recently electromechanical weirs have been used to assess the relative abundance of spawning-run sea lampreys in Lake Superior. Development of an integrated control approach to sea lamprey control has stimulated an ongoing research program to define structural and/or velocity criteria that can be used to design barrier dams that block spawning runs of sea lamprey.

Hunn, J. B.; Youngs, W. D.

1980-01-01

380

Medieval Warmth, Little Ice Age Cooling, and 20th Century Warming Reconstructed from Icelandic Lake Sediments  

Microsoft Academic Search

Historical records from Iceland provide one of the most compelling lines of evidence for North Atlantic warmth and reduced sea ice during Medieval times, colder summers and expanded sea ice during the Little Ice Age, followed by ameliorated conditions during the 20th century. Icelandic terrestrial records, particularly those derived from lake sediments, tend instead to be over-printed by the ancillary

A. Geirsdottir; G. Miller; M. Wooller; Y. Wang

2004-01-01

381

Lake Chad 2001  

NSDL National Science Digital Library

Sweep of Lake Chad, February 2001: Located on the edge of the Sahara and bordering four countries--Chad, Cameroon, Nigeria, and Niger--the immense area of this land locked lake has nearly disappeared in recent years. Persistent drought has caused the lake to drop from its former sixth place position in the list of worlds largest lakes; it is now one tenth its former size. The basin of the lake is not naturally deep, so the surface area of the lake tended to spread out, keeping the total depth to little more 23 feet (7 meters). In recent years, rainfall patterns have begun to change, and tributaries to Lake Chad have not been refilling the basin as rapidly as they used to. The lush, productive flora and fauna fed by the wetlands of the shallow lake have suffered as a result. This has led to significant changes for various communities of people that live in the vicinity of the lake. While for some the now exposed lake bed has enabled new land to be cultivated, much of the available fresh water that might have been used for irrigation is no longer dependable. As rainfall rates appear to be declining year after year, people living nearby develop even greater dependence on the lake, draining it even faster.

Thomson, Joycelyn; Snodgrass, Stuart; Coe, Michael

2001-02-26

382

Lengthening plus shortening of river-to-lake connection times in the Mackenzie River Delta respectively via two global change mechanisms along the arctic coast  

Microsoft Academic Search

River deltas along the circumpolar arctic coast are lake-rich and poorly understood ecosystems, set in a region expected to change rapidly. Over the past 30+ years annual river-to-lake connection times in the Mackenzie Delta have lengthened (>30 days) in the lowest elevation lakes and may have shortened in the highest elevation lakes, respectively via sea level rise and declining effects

Lance F. W. Lesack; Philip Marsh

2007-01-01

383

Preliminary Evaluation of a Lake Whitefish (Coregonus clupeaformis) Bioenergetics Model  

E-print Network

control of sea lamprey (Petromyzon marinus), a program that began in the 1960s (Wells and McLain 1973 have shown a strong recovery since the 1960s with the commercial harvest increasing more than tenfold P. Madenjian1 U.S. Geological Survey Great Lake Science Center 1451 Green Road Ann Arbor, Michigan

384

Biological Sciences AN ECOLOGICAL MAP OF FLORIDA'S LAKE WALES  

E-print Network

with Pleistocene shorelines defined by hypothetical sea level 45 #12;maxima and known contour lines (e.g., CookeBiological Sciences AN ECOLOGICAL MAP OF FLORIDA'S LAKE WALES RIDGE: A NEW BOUNDARY DELINEATION been recognized as a distinctive geomorphological and biogeographical feature of peninsular Florida

Weekley, Carl W.

385

COREGONID FISHES OF THE GREAT LAKES By WALTER KOELZ, Ph. D.  

E-print Network

_ Coregonus clupeaformis _ Lake Michigan _ Lake Huron _ Lake Superior _ Lake Nipigon _ Lake Erie _ Lake Superior _ Lake Nipigon _ artedi and artedi albus of Lake Ontario _ Leucichthys nipigon _ Genus Coregonus

386

Ecology of the Lake Huron fish community, 1970-1999  

USGS Publications Warehouse

We review the status of the Lake Huron fish community between 1970 and 1999 and explore the effects of key stressors. Offshore waters changed little in terms of nutrient enrichment, while phosphorus levels declined in inner Saginaw Bay. Introduced mussels (Dreissena spp.) proliferated and may have caused a decline in Diporeia spp. This introduction could have caused a decline in lake whitefish (Coregonus clupeaformis) growth and condition, with serious repercussions for commercial fisheries. Bythotrephes, an exotic predatory cladoceran, and other new exotics may be influencing the fish community. Sea lampreys (Petromyzon marinus) remained prevalent, but intensive control efforts on the St. Mary's River may reduce their predation on salmonines. Overfishing was less of a problem than in the past, although fishing continued to reduce the amount of lake trout (Salvelinus namaycush) spawning biomass resulting from hatchery-reared fish planted to rehabilitate this species. Massive stocking programs have increased the abundance of top predators, but lake trout were rehabilitated in only one area. Successful lake trout rehabilitation may require lower densities of introduced pelagic prey fish than were seen in the 1990s, along with continued stocking of hatchery-reared lake trout and control of sea lamprey. Such reductions in prey fish could limit Pacific salmon (Oncorhynchus spp.) fisheries.

Dobiesz, Norine E.; McLeish, David A.; Eshenroder, Randy L.; Bence, James R.; Mohr, Lloyd C.; Ebener, Mark P.; Nalepa, Thomas F.; Woldt, Aaron P.; Johnson, James E.; Argyle, Ray L.; Makarewicz, Joseph C.

2005-01-01

387

Sea growth of anadromous brown trout ( Salmo trutta)  

NASA Astrophysics Data System (ADS)

Sea growth rates were studied in anadromous brown trout caught in Lake IJsselmeer, The Netherlands. Growth in the first year at sea was estimated at 26 cm from length-frequency distributions, and at 21 cm from back-calculated growth rates from scale readings. These estimates are considerably higher than sea growth rates observed in populations at higher latitudes (Norway, Sweden), but compare well with the limited information on sea growth rates estimated for anadromous trout in the River Rhine and rivers in Normandy (France).

de Leeuw, J. J.; ter Hofstede, R.; Winter, H. V.

2007-08-01

388

Seismic Data Reveal Lake-Level Changes in Lake Issyk-Kul, Kyrgyzstan  

NASA Astrophysics Data System (ADS)

Lake Issyk-Kul is located in an intramontane basin of the Tien Shan, Kyrgyzstan, Central Asia, at 1607 m above sea level. It has formed in a tectonically active region with W-E striking major thrust zones both N and S of the lake. The lake is elongated with 180 km in W-E and 60 km in S-N direction and a water depth of roughly 670 m at its central plain. With a surface area of 6232 km2 and a total water colume of around 1736 km3, Lake Issyk-Kul is the second largest lake in the higher altitudes (De Batist et al., 2002). Two large delta areas have formed at the E and W end. Steep slopes at both the N and S shore separate rather narrow, shallow shelf areas from the central deeper plain. First seismic data of lake Issyk-Kul were acquired in 1982 by the Moscow University with a total of 31 profiles across the lake. In 1997 and 2001, a second and third seismic survey of the lake were carried out by the group of Marc De Batist (Ghent, Belgium) in cooperation with the Royal Museum of Central Africa (Tervuren, Belgium) and the SBRAS (Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia) using a sparker system with a single-channel streamer. These surveys were recently completed by a fourth expedition carried out by the University of Bremen in April 2013. During this expedition, 33 additional profiles were acquired with an airgun and a multi-channel streamer. The sparker surveys mostly cover the delta and shelf areas in high detail, while the airgun survey covers the deeper parts of the lake with penetration beyond the first multiple. Bathymetry data reveal that at the delta areas, the shelf is divided into two parts. The shallower comprises the part down to 110 m water depth with an average inclination of 0.5, while the deeper part reaches from 110 m to 300 m water depth with an average slope inclination of 1. Incised paleo-river channels of up to 2-3 km width and 50 m depth are visible both on the eastern and western shelf, but are limited to the shallower part of the deltas. They lie in the prolongation of modern river mouths at the eastern part of the lake, while at the western lake, they connect to former in- and outlets of the Chu River that is currently bypassing the lake (De Mol, 2006). A series of morphological terraces interpreted as ancient shorelines characterize the deeper part of the shelf. Together with lake-level terraces that are outcroping along the lake shores, the delta areas document up to 400 m of lake-level change. Deeper-penetrating multi-channel airgun profiles reveal that the sediments are mostly well-layered at least down to the multiple, and large-scale debris flows were detected only in some spots. The dipping of the layers increases with depth and reveals a halfgraben structure filled with lacustrine sediments. References: De Batist, M., et al., 2002. Bathymetry and sedimentary environments of Lake Issyk-Kul, Kyrgyz Republic (Central Asia): a large, high-altitude, tectonic lake. In: J. Klerkx and B. Imanackunov (Editors), Lake Issyk-Kul: Its Natural Environment. NATO Science Series, Series IV: Earth and Environmental Sciences. Kluwer Academic Publishers, Dordrecht, pp. 101-123. De Mol, L., 2006. Reconstructie van meerspiegelschommelingen in het Issyk-Kul Meer (Kirgizi) op basis van de geomorfologische en seismostratigrafische analyse van rivierdelta's. M.Sc. Thesis, University of Gent, Gent, 144 pp.

Gebhardt, C.; Spiess, V.; Keil, H.; Sauermilch, I.; Oberhnsli, H.; Abdrakhmatov, K.; De Batist, M. A.; Naudts, L.; De Mol, L.

2013-12-01

389

An abrupt drowning of the Black Sea shelf  

Microsoft Academic Search

During latest Quaternary glaciation, the Black Sea became a giant freshwater lake. The surface of this lake drew down to levels more than 100 m below its outlet. When the Mediterranean rose to the Bosporus sill at 7,150 yr BP11Unless otherwise noted, all dates reported are raw carbon-14 ages before reservoir corrections (460 yr) and thus are compatible with previously

William B. F. Ryan; Walter C. Pitman III; Candace O. Major; Kazimieras Shimkus; Vladamir Moskalenko; Glenn A. Jones; Petko Dimitrov; Naci Gorr

1997-01-01

390

Seasonal changes in bacterial diversity in the Salton Sea  

Microsoft Academic Search

The Salton Sea is a large, shallow, endorheic, polymictic, saline lake in Southern California sustained by runoff from local\\u000a agricultural and municipal wastewater. As a closed-basin lake in an arid region with declining water supply, it is becoming\\u000a increasingly saline. Due to its eutrophic status and episodic wind-driven mixing, basin-wide anoxia events are becoming more\\u000a common during summer. Sequencing of

Jesse G. Dillon; Lisa M. McMath; Amber L. Trout

2009-01-01

391

Chemical evolution of the Salton Sea, California: nutrient and selenium dynamics  

Microsoft Academic Search

The Salton Sea is a 1000-km2 terminal lake located in the desert area of southeastern California. This saline (~44?000 mg l-1 dissolved solids) lake started as fresh water in 190507 by accidental flooding of the Colorado River, and it is maintained by agricultural runoff of irrigation water diverted from the Colorado River. The Salton Sea and surrounding wetlands have recently

Roy A. Schroeder; William H. Orem; Yousif K. Kharaka

2002-01-01

392

Student Experiments at Sea (SEAS)  

NSDL National Science Digital Library

Interdisciplinary curriculum introduces the scientific process, experimental design and data analysis. Units on plate tectonics, hydrothermal vents, ridge visualization, surveying deep sea organisms. Students become the scientists, developing proposals for at-sea investigations, teacher coordinates submission to researchers studying the East Pacific Rise. Students retrieve, organize, analyze and report data from their experiment. Past experimental journals are posted. Free registration required to access curriculum and submit proposal.

2010-12-23

393

Water, Salt, Cotton and Soums: Shedding new Light on the Aral Sea Problem  

Microsoft Academic Search

In the late 1950ies, the Aral Sea, located in Central Asia, ranked as the fourth largest lake in the world. The annual water inflow by the Amu Darya and Syr Darya rivers balanced out the loss by evapotransporation at the 4 million ha of lake surface. Yet, since then, the area brought under irrigation by the use of the water

Christophera Martius; John Lamers; Paul L. G. Vlek; Omonbek Salaev

394

Pleurochrysis pseudoroscoffensis (Prymnesiophyceae) blooms on the surface of the Salton Sea, California  

Microsoft Academic Search

Dense populations of the coccolithophore Pleurochrysis pseudoroscoffensis were found in surface films at several locations around the Salton Sea in FebruaryAugust, 1999. An unidentified coccolithophorid was also found in low densities in earlier studies of the lake (19551956). To our knowledge, this is the first record of this widespread marine species in any lake. Samples taken from surface films typically

Kristen M. Reifel; Michael P. McCoy; MaryAnn Tiffany; Tonie E. Rocke; Charles C. Trees; Steven B. Barlow; D. John Faulkner; Stuart H. Hurlbert

2001-01-01

395

Sea level trends in South East Asian Seas (SEAS)  

NASA Astrophysics Data System (ADS)

Southeast Asian Seas (SEAS) span the largest archipelago in the global ocean and provide a complex oceanic pathway connecting the Pacific and Indian Oceans. The SEAS regional sea level trends are some of the highest observed in the modern satellite altimeter record that now spans almost two decades. Initial comparisons of global sea level reconstructions find that 17 year sea level trends over the past 60 years exhibit good agreement in areas and at times of strong signal to noise associated decadal variability forced by low frequency variations in Pacific trade winds. The SEAS region exhibits sea level trends that vary dramatically over the studied time period. This historical variation suggests that the strong regional sea level trends observed during the modern satellite altimeter record will abate as trade winds fluctuate on decadal and longer time scales. Furthermore, after removing the contribution of the Pacific Decadal Oscillation (PDO) to sea level trends in the past twenty years, the rate of sea level rise is greatly reduced in the SEAS region. As a result of the influence of the PDO, the SEAS regional sea level trends during 2010s and 2020s are likely to be less than the global mean sea level (GMSL) trend if the observed oscillations in wind forcing and sea level persist. Nevertheless, long-term sea level trends in the SEAS will continue to be affected by GMSL rise occurring now and in the future.

Strassburg, M. W.; Hamlington, B. D.; Leben, R. R.; Manurung, P.; Lumban Gaol, J.; Nababan, B.; Vignudelli, S.; Kim, K.-Y.

2014-10-01

396

Estimating the surface temperature of Lake Malawi using AVHRR and MODIS satellite imagery  

NASA Astrophysics Data System (ADS)

This paper discusses the potential offered by both Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery in estimating lake surface temperature. The findings from regression analysis show that MODIS/Terra Land Surface Temperature data (MOD11A1) and Ocean Color MODIS/Terra Sea Surface Temperature (SST)-SeaDAS data are closely related to in situ data as evidenced by a relatively high correlation coefficient ( r2 values of 0.7 and 0.74, respectively). In the light of the above, the developed algorithm may be used for estimating lake surface temperature over Lake Malawi from MODIS satellite imagery. Maps of temperature distribution that were generated for the lake from MODIS satellite imagery show that the circulation pattern of Lake Malawi is very complex, with no clear set pattern of temperature distribution over the entire lake. However, the persistence of a cold water zone between Salima and the northern part of Nkhotakota may be indicative of an upwelling region, ideal for the development of fishery industry. Inadequate satellite data made it difficult to assess whether or not the triple window equation previously developed by Wooster et al. [Wooster, M., Patterson, G., Loftie, R., Sear, C., 2001. Derivation and validation of the seasonal thermal structure of Lake Malawi using multi-satellite AVHRR observations. International Journal of Remote Sensing 22(15), 2953-2972] for estimating lake surface temperature using AVHRR was applicable to the entire lake.

Chavula, Geoffrey; Brezonik, Patrick; Thenkabail, Prasad; Johnson, Thomas; Bauer, Marvin

397

The Living Lakes  

NSDL National Science Digital Library

Living Lakes Partnership, a nonprofit organization has a goal to "create and support a network within which local lake organizations can find critical kinds of assistance for promoting sustainable development in lake areas." Their award winning site highlights nearly twenty lakes around the world, describing their individual, watershed, and biological characteristics as well as the geologic and human history of the area. The Living With Lakes section discusses lake management and conservation issues dealing with agriculture and urban areas (such as pollution and habitat loss). Other links include a photo gallery, news and events section, discussion groups, and much more. Visitors will enjoy the rich content and visuals that make up this site and will find themselves exploring it for some time and learning along the way.

2002-01-01

398

Savage Seas  

NSDL National Science Digital Library

This companion site to the new PBS series offers a collection of informative pieces and activities centered around the world's oceans. The site is divided into four principal sections, each of which features an article, brief sidebars, video clips, and in some cases, animations. The first, The Captain's Bridge, explores shipwrecks, stormy seas, and ocean rescues. The second, The Crow's Nest, dives into the power of waves. The Deep Sea section takes users to the nether regions of the ocean, while The Weather Factory touches on cyclones, ice and icebergs, and El Nino. Additional features at the site include Ask the Expert, Facts from the Sea, an annotated collection of related sites, and information about the series.

399

Lake Mead, NV  

NASA Technical Reports Server (NTRS)

Lake Mead, Nevada, (36.0N, 114.5E) where the water from the Colorado River empties after it's 273 mile journey through the Grand Canyon of Arizona is the subject of this photo. Other features of interest are Hoover Dam on the south shore of Lake Mead where cheap hydroelectric power is secondary to the water resources made available in this northern desert region and the resort city of Las Vegas, just to the west of Lake Mead.

1982-01-01

400

Sea Launch  

NSDL National Science Digital Library

Sea Launch is an international satellite launch service company that has a unique way of delivering payloads into space. With the launch platform situated on the equator in the middle of the Pacific Ocean, a specially designed rocket propels satellites into orbit with very good accuracy. The Sea Launch home page has plenty of information about its operation, including an overview of the technology, statistics about its successes and failures, and Webcasts of many of its launches. A 200+ page user's guide goes into detail about all the various stages of a mission; everything from design considerations for the spacecraft to transportation to the launch site is mentioned in the document.

401

DISTRIBUTION AND ORIGIN OF DIATOMS IN THE BOTTOM SEDIMENTS OF THE SUEZ CANAL LAKES AND ADJACENT AREAS, EGYPT  

Microsoft Academic Search

The diatom assemblages in the bottom sediments of Timsah Lake and adjacent sites, including the Great Bitter Lake, the northern part of the Gulf of Suez and the Mediterranean Sea at the entrance of the northern canal, have been recovered and studied in detail. A total of 394 species and varieties belonging to 96 genera were identified. Of these, 263

Abdelfattah A. Zalat

2002-01-01

402

Lake Tahoe Data Clearinghouse  

NSDL National Science Digital Library

The Lake Tahoe Data Clearinghouse Web site is part of the US Geological Survey's Lake Tahoe Initiative. The agency's goal for the site is to facilitate the coordination of research, monitoring, and environmental-management activities in the Lake Tahoe Basin and to ensure the widest possible access to data and information resulting from such activities. Products available include Digital Elevation Models, Digital Orthophoto Quadrangles, Digital Line Graphs, Digital Raster Graphics, maps and soil information of the area, and much more. The downloads include clear descriptions and examples for those unsure of the particular data types, making their use a snap for researchers, professionals, or anyone interested in the Lake Tahoe region. [JAB

Hoong, Connie

403

Grays Lake Ecosystem  

NSDL National Science Digital Library

This case study looks at the marsh ecosystem of Grays Lake in southeast Idaho, and is hosted by the Northern Prairie Wildlife Research Center (NPWRC). Grays Lake has been the focus of numerous research studies to understand factors affecting breeding water birds, habitat management practices, populations, and geological factors. This report gives general information about the Grays Lake ecosystem, including climate, habitats, plant communities, wildlife, water, and geology. More specific details are given through flora and fauna lists, historical and cultural overviews, details about the Grays Lake National Wildlife Refuge, and research information on management of wetlands.

404

A Killer Lake  

NSDL National Science Digital Library

In 1986, Lake Nyos, a volcanic lake in Cameroon, released a huge amount of carbon dioxide gas, killing over 1,700 people in the surrounding area. This case study, developed for use in a limnology or aquatic biology course, explores that event, introducing students to concepts relating to lake formation, thermal stratification, and dissolved gases. Students interpret graphs showing temperature, dissolved oxygen, pH, and conductivity measurements for the lake, and then synthesize these different types of limnological data to solve the problem.

Horvath, Thomas

2005-10-01

405

A Killer Lake  

NSDL National Science Digital Library

In 1986, Lake Nyos, a volcanic lake located in Cameroon, Africa, released a huge amount of carbon dioxide gas, killing over 1,700 people and countless livestock and other animals in the area. This case, intended for use in a limnology or an aquatic biology course, explores that event, introducing students to concepts related to lake formation, thermal stratification, and dissolved gases. Students interpret graphs containing temperature, dissolved oxygen, pH, and conductivity data for the lake, and then synthesize these different types of limnological data to understand what happened.

Horvath, Thomas

2005-01-01

406

Great Lakes Literacy Principles  

NASA Astrophysics Data System (ADS)

Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These Great Lakes Literacy Principles represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

Fortner, Rosanne W.; Manzo, Lyndsey

2011-03-01

407

Lake Roosevelt Fisheries and Limnological Research : 1996 Annual Report.  

SciTech Connect

The Lake Roosevelt Monitoring/Data Collection Program resulted from a merger between the Lake Roosevelt Monitoring Program and the Lake Roosevelt Data Collection Project. This project will model biological responses to reservoir operations, evaluate the effects of releasing hatchery origin kokanee salmon and rainbow trout on the fishery, and evaluate the success of various stocking strategies. In 1996, limnological, reservoir operation, zooplankton, and tagging data were collected. Mean reservoir elevation, storage volume and water retention time were reduced in 1996 relative to the last five years. In 1996, Lake Roosevelt reached a yearly low of 1,227 feet above mean sea level in April, a yearly high of 1,289 feet in July, and a mean yearly reservoir elevation of 1,271.4 feet. Mean monthly water retention times in Lake Roosevelt during 1996 ranged from 15.7 days in May to 49.2 days in October. Average zooplankton densities and biomass were lower in 1996 than 1995. Daphnia spp. and total zooplankton densities peaked during the summer, whereas minimum densities occurred during the spring. Approximately 300,000 kokanee salmon and 400,000 rainbow trout were released into Lake Roosevelt in 1996. The authors estimated 195,628 angler trips to Lake Roosevelt during 1996 with an economic value of $7,629,492.

Cichosz, Thomas A.; Underwood, Keith D.; Shields, John; Scholz, Allan; Tilson, Mary Beth

1997-05-01

408

Sea ice in the China Sea  

SciTech Connect

In every winter, sea ice occurring in Bohai Sea and the North Yellow Sea is the first-year ice which is going through generating, developing and thawing processes. Therefore, it is necessary to spatially and temporally describe ice period, freezing range, thickness variations and general motion of sea ice. The purpose of this paper is to provide initial general situation and features of sea ice for forecasting and researching sea ice.

Deng Shuqi [National Research Center for Marine Environmental Forecasts, Beijing (China)

1993-12-31

409

The Use of Enzyme Hydrolysis to Assess the Seasonal Mobility and Bioavailability of Organic Phosphorus in Lake Sediments  

NASA Astrophysics Data System (ADS)

Lake sediments represent a significant internal source of phosphorus (P) in eutrophic freshwater systems during periods of high biological activity and oxygen depletion in sediments. Enzyme-labile and redox-sensitive P fractions may be a major component of the mobile sediment P pool which contributes to the development of harmful algal blooms. We present a high-through-put enzyme-based method for assessing potentially bioavailable (enzyme-labile) P in lake sediments and describe the relationship between enzyme-labile P, ascorbate-extractable (reactive) P and metals (Fe, Mn, Al, Ca), and P species identified using solution 31-P NMR spectroscopy. Sediment cores (0-10 cm) were collected from Lake Champlain over multiple years (Missisquoi Bay, VT, USA; 2007-2013). A principal components analysis of sediment properties suggests that enzyme-labile and reactive P, Mn, and Fe concentrations were more effective than the 31-P NMR methodology alone for differentiating algal bloom stage associated with periods of sediment anoxia. Bloom onset (July 2008) and peak bloom (August 2008, 2012) periods corresponded to the highest enzyme-labile P and lowest reactive P and metals proportions, despite 31-P NMR profiles which did not change significantly with respect to time and depth. High levels of reduced Fe and Mn ions were also detected in pore-water during this period, confirming previous reports that organic P bioavailability is linked to the redox status of sediments. High through-put analysis of enzyme-labile P fractions will provide spatially and temporally resolved information on bioavailable P pools at lower cost than traditional methods (i.e., 31-P NMR), and provide much-needed detail on aquatic P cycles during discrete stages of algal bloom development and sediment anoxia.

Giles, C. D.; Lee, L. G.; Cade-Menun, B. J.; Rutila, B. C.; Schroth, A. W.; Xu, Y.; Hill, J. E.; Druschel, G.

2013-12-01

410

Aral Sea; Irretrievable Loss or Irtysh Imports?  

Microsoft Academic Search

The Aral Sea has shrunk and become a large salt pan, because the water from the two rivers that used to feed the lake (Amu\\u000a Darya and Syr Darya) is almost entirely used for irrigation. In this paper some possibilities to return to the original (1960)\\u000a situation are studied. After discussing some of the alternatives, it is proposed to construct

Viorel Badescu; Roelof D. Schuiling

2010-01-01

411

Celtic Sea  

... carbonate. The plates, or coccoliths, give the ocean a milky white or turquoise appearance during intense blooms. The long-term flux of ... Sea for several weeks in summer. The coccoliths backscatter light from the water column to create a bright optical effect. Other algal ...

2013-04-17

412

Ten years of limnological monitoring of a modified natural lake in the tropics: Cote Lake, Costa Rica.  

PubMed

It is located 650m above sea level along the boundary between the North Caribbean and Pacific slopes, near the Southern end of the volcanic Guanacaste mountain range. In the early 1980s the lake's main outlet was dammed and the outflow was diverted into Arenal Reservoir. Lake Cote was first studied in 1990-1991, and later in 2001, before it was again modified by raising its dam by one meter to use its outflow for hydroelectricity. From 2002 to 2010 it has been monitored twice a year for changes in its limnology. Here I present a summary of its basic characteristics and an analysis of their changes through time. The lake is discontinuous polymictic, and sometimes develops a thermocline at 6m depth that may last for several days as evidenced by the occasional development of an anoxic layer close to the bottom. Since its modification for hydropower production, the surface water temperature has attained higher values than before. Oxygen levels in the lake show periods of hypoxia to anoxia in the hypolimnion, that have become more frequent since modification. Despite its turbid water, the lake has low levels of nutrient concentrations and of chlorophyll a. The trend in these parameters in recent times is a reduction in chlorophyll a and an increase in water transparency, implying a reduction in primary productivity. These changes are discussed in relationship with anthropogenic factors such as the modification of the lake and its management, changes in landscape around the lake and global climate change. PMID:25102640

Umaa, Gerardo

2014-06-01

413

Hydrogeology, hydrologic budget, and water chemistry of the Medina Lake area, Texas  

USGS Publications Warehouse

A three-phase study of the Medina Lake area in Texas was done to assess the hydrogeology and hydrology of Medina and Diversion Lakes combined (the lake system) and to determine what fraction of seepage losses from the lake system might enter the regional ground-water-flow system of the Edwards and (or) Trinity aquifers. Phase 1 consisted of revising the geologic framework for the Medina Lake area. Results of field mapping show that the upper member of the Glen Rose Limestone underlies Medina Lake and the intervening stream channel from the outflow of Medina Lake to the midpoint of Diversion Lake, where the Diversion Lake fault intersects Diversion Lake. A thin sequence of strata consisting primarily of the basal nodular and dolomitic members of the Kainer Formation of the Edwards Group, is present in the southern part of the study area. On the southern side of Medina Lake, the contact between the upper member of the Glen Rose Limestone and the basal nodular member is approximately 1,000 feet above mean sea level, and the contact between the basal nodular member and the dolomitic member is approximately 1,050 feet above mean sea level. The most porous and permeable part of the basal nodular member is about 1,045 feet above mean sea level. At these altitudes, Medina Lake is in hydrologic connection with rocks in the Edwards aquifer recharge zone, and Medina Lake appears to lose more water to the ground-water system along this bedding plane contact. Hydrologic budgets calculated during phase 2 for Medina Lake, Diversion Lake, and Medina/Diversion Lakes combined indicate that: (1) losses from Medina and Diversion Lakes can be quantified; (2) a portion of those losses are entering the Edwards aquifer; and (3) losses to the Trinity aquifer in the Medina Lake area are minimal and within the error of the hydrologic budgets. Hydrologic budgets based on streamflow, precipitation, evaporation, and change in lake storage were used to quantify losses (recharge) to the ground-water system from Medina Lake, Diversion Lake, and Medina/Diversion Lakes combined during October 1995?September 1996. Water losses from Medina Lake to the Edwards/Trinity aquifers ranged from -14.0 to 135 acre-feet per day; Diversion Lake ranged from -1.2 to 93.1 acre-feet per day; and Medina/Diversion Lakes combined ranged from 36.1 to 119 acre-feet per day. Monthly average recharge during December 1995?July 1996 was estimated using an alternative method developed during this study (current study method) and compared to monthly average recharge during December 1995?July 1996 estimated using the existing USGS method and the Trans-Texas method. Recharge to the Edwards aquifer estimated using the current study method was about 69 and 73 percent of the recharge estimated using the USGS and Trans-Texas methods, respectively. The USGS and Trans-Texas methods overestimated recharge from Medina Lake compared to the recharge estimated with the current study method when Medina Lake stage was between about 1,027 and 1,032 feet above mean sea level and underestimated recharge from Medina Lake when lake stage was between about 1,036 and 1,045 feet above mean sea level. The USGS and Trans-Texas methods underestimated recharge from Diversion Lake compared to the recharge estimated with the current study method when Diversion Lake stage was greater than 913 feet above mean sea level and overestimated recharge from Diversion Lake when lake stage was less than 913 feet above mean sea level. The water quality of Medina Lake and Medina River and in selected wells and springs in the Edwards and Trinity aquifers was characterized during phase 3 of the study. Environmental isotope analyses and geochemical modeling also were used to determine where water losses from the lake system might be entering the ground-water-flow system. Isotopic ratios of deuterium, oxygen, and strontium were analyzed in selected surface-water, lake-water, and ground-water samples to trace the isotopi

Lambert, Rebecca B.; Grimm, Kenneth C.; Lee, Roger W.

2000-01-01

414

Crater Lake revealed  

USGS Publications Warehouse

Around 500,000 people each year visit Crater Lake National Park in the Cascade Range of southern Oregon. Volcanic peaks, evergreen forests, and Crater Lakes incredibly blue water are the parks main attractions. Crater Lake partially fills the caldera that formed approximately 7,700 years ago by the eruption and subsequent collapse of a 12,000-foot volcano called Mount Mazama. The caldera-forming or climactic eruption of Mount Mazama drastically changed the landscape all around the volcano and spread a blanket of volcanic ash at least as far away as southern Canada. Prior to the climactic event, Mount Mazama had a 400,000 year history of cone building activity like that of other Cascade volcanoes such as Mount Shasta. Since the climactic eruption, there have been several less violent, smaller postcaldera eruptions within the caldera itself. However, relatively little was known about the specifics of these eruptions because their products were obscured beneath Crater Lakes surface. As the Crater Lake region is still potentially volcanically active, understanding past eruptive events is important to understanding future eruptions, which could threaten facilities and people at Crater Lake National Park and the major transportation corridor east of the Cascades. Recently, the lake bottom was mapped with a high-resolution multibeam echo sounder. The new bathymetric survey provides a 2m/pixel view of the lake floor from its deepest basins virtually to the shoreline. Using Geographic Information Systems (GIS) applications, the bathymetry data can be visualized and analyzed to shed light on the geology, geomorphology, and geologic history of Crater Lake.

Ramsey, David W.; Dartnell, Peter; Bacon, Charles R.; Robinson, Joel E.; Gardner, James V.

2003-01-01

415

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research  

E-print Network

The rehabilitation of extirpated lake trout (Salvelinus namaycush) in the Great Lakes and Lake Champlain has been. © 2009 Elsevier Inc. All rights reserved. Introduction Lake trout (Salvelinus namaycush) is the focus

Marsden, Ellen

416

The Great Lakes.  

ERIC Educational Resources Information Center

The Great Lakes are one of the world's greatest reserviors of fresh water, the foundation of Ontario's economic development, a primary force in ecological systems, and a base for pleasure and recreation. These lakes and their relationship with people of Canada and the United States can be useful as a subject for teaching the impact of human

Seasons, 1987

1987-01-01

417

Great Lakes: Great Gardening.  

ERIC Educational Resources Information Center

This folder contains 12 fact sheets designed to improve the quality of gardens near the Great Lakes. The titles are: (1) "Your Garden and the Great Lakes"; (2) "Organic Gardening"; (3) "Fruit and Vegetable Gardening"; (4) "Composting Yard Wastes"; (5) "Herbicides and Water Quality"; (6) "Watering"; (7) "Soil Erosion by Water"; (8) "Soil

New York Sea Grant Inst., Albany, NY.

418

Great Lakes Teacher's Guide.  

ERIC Educational Resources Information Center

The Great Lakes are one of the world's greatest reservoirs of fresh water, the foundation of Ontario's economic development, a primary force in ecological systems, and a base for pleasure and recreation. They are also a magnificent resource for the teachers of Ontario. Study of the Great Lakes can bring to life the factors that shape the ecology

Reid, Ron

419

The lakes of Titan  

USGS Publications Warehouse

The surface of Saturn's haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface. Initial visible and radar imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on the surface. Here we provide definitive evidence for the presence of lakes on the surface of Titan, obtained during the Cassini Radar flyby of Titan on 22 July 2006 (T16). The radar imaging polewards of 70?? north shows more than 75 circular to irregular radar-dark patches, in a region where liquid methane and ethane are expected to be abundant and stable on the surface. The radar-dark patches are interpreted as lakes on the basis of their very low radar reflectivity and morphological similarities to lakes, including associated channels and location in topographic depressions. Some of the lakes do not completely fill the depressions in which they lie, and apparently dry depressions are present. We interpret this to indicate that lakes are present in a number of states, including partly dry and liquid-filled. These northern-hemisphere lakes constitute the strongest evidence yet that a condensable-liquid hydrological cycle is active in Titan's surface and atmosphere, in which the lakes are filled through rainfall and/or intersection with the subsurface 'liquid methane' table. ??2007 Nature Publishing Group.

Stofan, E. R.; Elachi, C.; Lunine, J. I.; Lorenz, R. D.; Stiles, B.; Mitchell, K. L.; Ostro, S.; Soderblom, L.; Wood, C.; Zebker, H.; Wall, S.; Janssen, M.; Kirk, R.; Lopes, R.; Paganelli, F.; Radebaugh, J.; Wye, L.; Anderson, Y.; Allison, M.; Boehmer, R.; Callahan, P.; Encrenaz, P.; Flamini, E.; Francescetti, G.; Gim, Y.; Hamilton, G.; Hensley, S.; Johnson, W. T. K.; Kelleher, K.; Muhleman, D.; Paillou, P.; Picardi, G.; Posa, F.; Roth, L.; Seu, R.; Shaffer, S.; Vetrella, S.; West, R.

2007-01-01

420

The lakes of Titan  

NASA Astrophysics Data System (ADS)

The surface of Saturn's haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface. Initial visible and radar imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on the surface. Here we provide definitive evidence for the presence of lakes on the surface of Titan, obtained during the Cassini Radar flyby of Titan on 22 July 2006 (T16). The radar imaging polewards of 70 north shows more than 75 circular to irregular radar-dark patches, in a region where liquid methane and ethane are expected to be abundant and stable on the surface. The radar-dark patches are interpreted as lakes on the basis of their very low radar reflectivity and morphological similarities to lakes, including associated channels and location in topographic depressions. Some of the lakes do not completely fill the depressions in which they lie, and apparently dry depressions are present. We interpret this to indicate that lakes are present in a number of states, including partly dry and liquid-filled. These northern-hemisphere lakes constitute the strongest evidence yet that a condensable-liquid hydrological cycle is active in Titan's surface and atmosphere, in which the lakes are filled through rainfall and/or intersection with the subsurface `liquid methane' table.

Stofan, E. R.; Elachi, C.; Lunine, J. I.; Lorenz, R. D.; Stiles, B.; Mitchell, K. L.; Ostro, S.; Soderblom, L.; Wood, C.; Zebker, H.; Wall, S.; Janssen, M.; Kirk, R.; Lopes, R.; Paganelli, F.; Radebaugh, J.; Wye, L.; Anderson, Y.; Allison, M.; Boehmer, R.; Callahan, P.; Encrenaz, P.; Flamini, E.; Francescetti, G.; Gim, Y.; Hamilton, G.; Hensley, S.; Johnson, W. T. K.; Kelleher, K.; Muhleman, D.; Paillou, P.; Picardi, G.; Posa, F.; Roth, L.; Seu, R.; Shaffer, S.; Vetrella, S.; West, R.

2007-01-01

421

Evaporation From Lake Superior  

NASA Astrophysics Data System (ADS)

Evaporation is a critical component of the water balance of each of the Laurentian Great Lakes, and understanding the magnitude and physical controls of evaporative water losses are important for several reasons. Recently, low water levels in Lakes Superior and Michigan/Huron have had socioeconomic, ecological, and even meteorological impacts (e.g. water quality and quantity, transportation, invasive species, recreation, etc.). The recent low water levels may be due to increased evaporation, but this is not known as operational evaporation estimates are currently calculated as the residual of water or heat budgets. Perhaps surprisingly, almost nothing is known about evaporation dynamics from Lake Superior and few direct measurements of evaporation have been made from any of the Laurentian Great Lakes. This research is the first to attempt to directly measure evaporation from Lake Superior by deploying eddy covariance instrumentation. Results of evaporation rates, their patterns and controlling mechanisms will be presented. The direct measurements of evaporation are used with concurrent satellite and climate model data to extrapolate evaporation measurements across the entire lake. This knowledge could improve predictions of how climate change may impact the lake's water budget and subsequently how the water in the lake is managed.

Spence, C.; Blanken, P.; Hedstrom, N.; Leshkevich, G.; Fortin, V.; Charpentier, D.; Haywood, H.

2009-05-01

422

Lessons from a Lake.  

ERIC Educational Resources Information Center

Describes a study that included classroom lessons on hydroelectric power, the history and construction of a nearby lake, data recording, the use of field guides, and methods of counting natural populations. The study culminated in a field trip to the lake. (JRH)

Goethals, Susan

1997-01-01

423

Antarctic subglacial lake discharges  

NASA Astrophysics Data System (ADS)

Antarctic subglacial lakes were long time supposed to be relatively closed and stable environments with long residence times and slow circulations. This view has recently been challenged with evidence of active subglacial lake discharge underneath the Antarctic ice sheet. Satellite altimetry observations witnessed rapid changes in surface elevation across subglacial lakes over periods ranging from several months to more than a year, which were interpreted as subglacial lake discharge and subsequent lake filling, and which seem to be a common and widespread feature. Such discharges are comparable to jkulhlaups and can be modeled that way using the Nye-Rthlisberger theory. Considering the ice at the base of the ice sheet at pressure melting point, subglacial conduits are sustainable over periods of more than a year and over distances of several hundreds of kilometers. Coupling of an ice sheet model to a subglacial lake system demonstrated that small changes in surface slope are sufficient to start and sustain episodic subglacial drainage events on decadal time scales. Therefore, lake discharge may well be a common feature of the subglacial hydrological system, influencing the behavior of large ice sheets, especially when subglacial lakes are perched at or near the onset of large outlet glaciers and ice streams. While most of the observed discharge events are relatively small (101-102 m3 s-1), evidence for larger subglacial discharges is found in ice free areas bordering Antarctica, and witnessing subglacial floods of more than 106 m3 s-1 that occurred during the middle Miocene.

Pattyn, Frank

424

Lake Wobegon Dice  

ERIC Educational Resources Information Center

We introduce Lake Wobegon dice, where each die is "better than the set average." Specifically, these dice have the paradoxical property that on every roll, each die is more likely to roll greater than the set average on the roll, than less than this set average. We also show how to construct minimal optimal Lake Wobegon sets for all "n" [greater

Moraleda, Jorge; Stork, David G.

2012-01-01

425

Venezuela: Lake Maracaibo  

article title: Oil Slicks on Lake Maracaibo, Venezuela View Larger Image Several oil slicks occurred on Lake Maracaibo in northwestern Venezuela between ... wave facets divert reflected rays into many directions. An oil film dampens the presence of small wind-driven "capillary" waves, resulting ...

2013-04-18

426

Great Lakes: chemical monitoring  

Microsoft Academic Search

The article discusses a symposium sponsored by the 10th Great Lakes Regional Meeting of the American Chemical Society (ACS) that addressed various aspects of the theme ''Chemistry of the Great Lakes''. The symposium attempted to gather together environmental information produced by chemists, and included: watershed studies, involving investigation of the sources, transport, and fate of sterols in the Menomonee River;

Joseph J. Delfino

1976-01-01

427

Mirror Lake Spring 2008  

E-print Network

. This was the first recorded bloom on Mirror Lake. Prompted partially by the algal bloom of 2007, the fall semester a cyanobacterial bloom took place at Mirror Lake, causing local authorities (though not the New Hampshire exceeds the 10 µg/l value necessary for cyanobacterial blooms (Table 1.1), and a high concentration

New Hampshire, University of

428

Growth and Survival of Newly Parasitic Sea Lampreys at Representative Winter Temperatures  

Microsoft Academic Search

Larval sea lampreys Petromyzon marinus begin to metamorphose into their parasitic phase in July and migrate to the Great Lakes either in autumn, when they immediately feed on fish, or in spring after overwintering in the stream substrate. Survival and growth of newly parasitic autumn migrants (mean weight, 4.18 g) differed significantly between temperature treatments when sea lampreys were held

William D. Swink

1995-01-01

429

Modelling the impact of Global Change on the hydrological system of the Aral Sea basin  

Microsoft Academic Search

During the last decades the Aral Sea basin has suffered an enormous depletion of water resources within its lakes and rivers with consequences for society, economy, and nature. Within this model study, Global Change impacts on the Amu Darya and Syr Darya rivers, as well as on the Aral Sea itself, are being analysed for the period 19582002. In a

T. Aus der Beek; F. Vo; M. Flrke

2011-01-01

430

Is the abrupt drowning of the Black Sea shelf at 7150 yr bp a myth?  

Microsoft Academic Search

Sedimentological and chronostratigraphic studies of the coastal plain sediments of the Black Sea near the Sakarya River (Turkey) and seismicstratigraphic survey of the shelf sediments off this river's mouth were carried out. The results indicate that just prior to its flooding by the Mediterranean waters at about 7200yrbp, the Black Sea was a fresh water lake, emptying its waters into

Naci Grr; M. Nam?k a?atay; mer Emre; Bedri Alpar; Mehmet Sak?n; Ye?im ?slamo?lu; Oya Algan; Tevfik Erkal; Mustafa Keer; Remzi Akkk; Glin Karl?k

2001-01-01

431

Global Warming and Sea Level Rise: the Past, Present, and Future  

E-print Network

1 Global Warming and Sea Level Rise: the Past, Present, and Future Paul Liu jpliu@ncsu.edu MEAS recent Warming up, With some cooling events #12;The time series shows the combined global land and marine;19 Evidence · Ice cores · Deep sea cores · Coral reef · Lake · Loess · Stalagmite · ... #12;20 Drill

Parker, Matthew D. Brown

432

The benthic invertebrates of the Salton Sea: distribution and seasonal dynamics  

Microsoft Academic Search

The Salton Sea, California's largest inland water body, is an athalassic saline lake with an invertebrate fauna dominated by marine species. The distribution and seasonal dynamics of the benthic macroinvertebrate populations of the Salton Sea were investigated during 1999 in the first survey of the benthos since 1956. Invertebrates were sampled from sediments at depths of 212 m, shallow water

P. M. Detwiler; Marie F. Coe; Deborah M. Dexter

2002-01-01

433

Disiccation of the Aral Sea: A Water Management Disaster in the Soviet Union  

Microsoft Academic Search

The Aral Sea in the Soviet Union, formerly the world's fourth largest lake in area, is disappearing. Between 1960 and 1987, its level dropped nearly 13 meters, and its area decreased by 40 percent. Recession has resulted from reduced inflow caused primarily by withdrawals of water for irrigation. Severe environmental problems have resulted. The sea could dry to a residual

Philip P. Micklin

1988-01-01

434

The conservation ecology of the Podonidae from the Caspian and Aral seas  

Microsoft Academic Search

Results of five expeditions to the Caspian Sea and 17 expeditions to the Aral Sea from 19761993 are presented. In these two large salt lakes, nine species of Podonidae were found, all of which were fairly euryhaline, except Caspievadne maximowitschi. Further, all of them were thermophilic, except Cornigerius bicornis, Caspievadne maximowitschi, and Pleopis polyphemoides. Sexual reproduction of the Podonidae in

N. V. Aladin

1995-01-01

435

Dramatic Evaporation of the Aral Sea (with dates)  

NSDL National Science Digital Library

DISAPPEARING WATER: THE ARAL SEA OVER TIME, FROM 1973 TO 2001 A time series is a powerful illustrative tool. Where in the case of Las Vegas we see the direct effects of people on the land, in the case of the Aral Sea, separating the countries of Kazakhstan and Uzbekistan, we see indirect, but no less dramatic effects on a different part of the world. The Aral Sea is actually not a sea at all. It is an immense lake, a body of fresh water, although that particular description of its contents might now be more a figure of speech than practical fact. In the last thirty years, more than sixty percent of the lake has disappeared. As youll see in the visualization, the change over time is dramatic. In the 1970s, farmers and state offices opened significant diversions from the rivers supplying water to the lake, sending millions of gallons to irrigate cotton fields and rice paddies. So voluminous were these irrigation sluices that concentrations of salts and minerals began to rise in the shrinking body of water. That change in chemistry has led to staggering alterations in the lakes ecology, causing precipitous drops in the Arals fish population. A secondary effect of this reduction in the Aral Seas overall size is the rapid exposure of the lake bed. Powerful winds that blow across this part of Asia routinely pick up and deposit tens of thousands of tons of now exposed soil every year. This has not only contributed to significant reduction in breathable air quality for nearby residents, but also appreciably affected crop yields due to those heavily salt laden particles falling on arable land. In the following sequence of images, we see a series of Landsat scenes taken several years apart. As the years pass, we see the profound reduction in overall area covered by the Aral, and a commensurate increase in land area as the floor of the sea now lies exposed.

Thomson, Joycelyn; Williams, Darrel

2001-04-19

436

Acidification of Adirondack lakes  

SciTech Connect

The acidification of lakes in the Adirondack Mountain region of New York was estimated directly by comparing data from historic (1929-1934) and modern (1975-1985) regional surveys of lake chemistry. The authors performed new analyses concerning the quality of the data, rejecting all historic pH data and many modern alkalinity values. When the historic data were corrected for a bias between titration procedures, they found a median loss of 50 ..mu..equiv/L alkalinity in 274 lakes with paired data. Eighty percent of the lakes showed a decline in alkalinity. The observed acidification was greatest in the lakes at high elevation and was of the same magnitude as the current precipitation acidity in the region.

Asbury, C.E.; Vertucci, F.A.; Mattson, M.D.; Likens, G.E.

1989-03-01

437

Database compilation: hydrology of Lake Tiberias (Jordan Valley)  

NASA Astrophysics Data System (ADS)

A long-term series of water balance data over the last 50 years is compiled to gain insights into the hydrology of the Lake Tiberias (LT) and surrounding aquifers. This database is used within the framework of a German-Israeli-Jordanian project (DFG Ma4450-2) in which numerical modeling is applied to study the mechanisms of deep fluid transport processes affecting the Tiberias basin. The LT is the largest natural freshwater lake in Israel. It is located in the northern part of the Dead Sea Rift. The behavior of the lake level is a result of the regional water balance caused mainly by interaction of two factors: (i) fluctuations of water inflow to the Lake, (ii) water exploitation in the adjacent aquifers and consumptions from the lake (pumping, diversion, etc). The replenishment of the lake occurs through drainage from surrounding mountains (Galilee, Golan Heights), entering the lake through the Jordan River and secondary streams (85%), direct precipitation (11%), fresh-saline springs discharging along the shoreline, divertion from Yarmouk river and internal springs and seeps. The major losses occur through the National Water Carrier (ca. 44%), evaporation (38%), local consumption and compensation to Jordan (in sum 12%). In spite of the increasing role of water exploitation, the natural inflow to the Lake remains the dominant factor of hydrological regime of the Tiberias Lake. Additionally, series of natural yield to the LT are reconstructed with precipitation data measured in the Tiberias basin (1922-2012). The earlier period (1877-1921) is evaluated considering long rainfall records at Beirut and Nazareth stations (Middle East Region). This data enables to use the LT yield as a complex indicator of the regional climate change. Though the data applies to the LT, this example shows the importance of large database. Their compilation defines the correct set-up of joint methodologies such as numerical modeling and hydrochemical analyses aimed to understand large-scale hydrological processes.

Shentsis, Izabela; Rosenthal, Eliyahu; Magri, Fabien

2014-05-01

438

Polar lake circulation during ice break-up  

NASA Astrophysics Data System (ADS)

An extensive dataset on lake physical properties has been collected during the final stage of the ice-covered period in May-June 2013 in polar Lake Kilpisjrvi, Finland. The data reveal several important features of lake dynamics, which shed new light on the mechanism of ice cover break-up and ice melting in lakes and marginal seas. CTD transects with high spatial resolution showed up a 300m-wide upwelling zone in the center of the lake, driven by downslope converging flow of warm waters from open-water 'moat' along the lake shoreline. The resulting radial density gradient, balanced by the Coriolis force, created a lake-wide anti-cyclonically rotating gyre with a measured peak azimuthal velocity of 0.05 m/s. Appreciable marginal heating is driven in polar enclosed basins by high amount of solar radiation and by surface inflow of meltwater. Hence, quasi-geostrophic anticyclonic circulation is suggested to be a general feature of polar lakes, redistributing heat within a water body and potentially accelerating ice melting. In addition, high-resolution records of pressure, current velocities and water temperature revealed under-ice seiches with periods of 10 to 25 min. The ice breakup was associated with 10 times increase of seiche amplitudes under ice. The seiches decayed within 10-15 hours; during this short period, the previously ice-covered lake became ice-free. We suggest that seiche-driven vertical motions of the soft ice sheet contribute significantly to breaking and melting of seasonal ice in enclosed reservoirs.

Kirillin, Georgiy; Forrest, Alexander; Graves, Kelly; Laval, Bernard

2014-05-01

439

Geochronology and Stratigraphy of Pluvial Argentinean Lakes: Implications for Quaternary Climate Change  

NASA Astrophysics Data System (ADS)

Shoreline deposits of pluvial lake systems can provide direct evidence of the timing and duration of lake high stands. Complemented by careful stratigraphic and geochemical analysis, these records also contain important paleoenvironmental information. Two lake systems were studied as part of a global effort to understand major climatic changes during the Last Glacial Maximum (LGM: 24-18 ka) and the following deglaciation (18-13 ka). Today, both of the studied regions are arid, and the lake basins contain much smaller lakes than in the past. Laguna Cari-Laufquen is located at 41S and the modern basin is occupied by two lakes: Cari-Laufquen Grande and Chica. Preserved shorelines and sediments show these two lakes rose and merged multiple times during the Late Quaternary. An extensive radiocarbon geochronology show the lake was the highest during the LGM, with several smaller, more recent lake oscillations in the last thousand years. The second lake system in this study is Laguna Bebedero, located at 33S in western Argentina. Previous studies show the highest shorelines date to 23-16,000 yrs BP. Our new radiocarbon dates help constrain the timing of the highstands - and show highstands during the deglacial period. Our lake highstand evidence provides a unique opportunity to reconstruct shifts in Atlantic (easterly)- or Pacific (westerly)-driven moisture. Geochemical studies of shell, water chemical analysis, and geospatial analysis also help to constrain hydrologic balance and paleoenvironmental conditions. Comparison of paleohydrologic records in South America. From top: Cariaco Basin - reconstructed sea-surface temperatures from Lea et al., 2003, Bolivian Lakes - Uyuni lake system phases from shoreline data (Placzek et al., 2006), Atacama Wetlands - wet events above local water table (Quade et al., 2008), Laguna Bebedero and Laguna Cari-Laufquen - lake level changes from this study.

Cartwright, A.

2009-12-01

440

Evidence of offshore lake trout reproduction in Lake Huron  

USGS Publications Warehouse

Six Fathom Bank-Yankee Reef, an offshore reef complex, was an historically important spawning area believed to represent some of the best habitat for the rehabilitation of lake trout Salvelinus namaycush in Lake Huron. Since 1986, lake trout have been stocked on these offshore reefs to reestablish self-sustaining populations. We sampled with beam trawls to determine the abundance of naturally reproduced age-0 lake trout on these offshore reefs during May-July in 1994-1998 and 2000-2002. In total, 123 naturally reproduced lake trout fry were caught at Six Fathom Bank, and 2 naturally reproduced lake trout fry were caught at nearby Yankee Reef. Our findings suggest that this region of Lake Huron contains suitable habitat for lake trout spawning and offers hope that lake trout rehabilitation can be achieved in the main basin of Lake Huron.

DeSorcie, Timothy J.; Bowen, Charles A., II

2003-01-01

441

Marine incursion: the freshwater herring of Lake Tanganyika are the product of a marine invasion into west Africa.  

PubMed

The spectacular marine-like diversity of the endemic fauna of Lake Tanganyika, the oldest of the African Great Lakes, led early researchers to suggest that the lake must have once been connected to the ocean. Recent geophysical reconstructions clearly indicate that Lake Tanganyika formed by rifting in the African subcontinent and was never directly linked to the sea. Although the Lake has a high proportion of specialized endemics, the absence of close relatives outside Tanganyika has complicated phylogeographic reconstructions of the timing of lake colonization and intralacustrine diversification. The freshwater herring of Lake Tanganyika are members of a large group of pellonuline herring found in western and southern Africa, offering one of the best opportunities to trace the evolutionary history of members of Tanganyika's biota. Molecular phylogenetic reconstructions indicate that herring colonized West Africa 25-50MYA, at the end of a major marine incursion in the region. Pellonuline herring subsequently experienced an evolutionary radiation in West Africa, spreading across the continent and reaching East Africa's Lake Tanganyika during its early formation. While Lake Tanganyika has never been directly connected with the sea, the endemic freshwater herring of the lake are the descendents of an ancient marine incursion, a scenario which may also explain the origin of other Tanganyikan endemics. PMID:18431469

Wilson, Anthony B; Teugels, Guy G; Meyer, Axel

2008-01-01