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1

75 FR 82061 - Lake Champlain Sea Lamprey Control Alternatives Workgroup  

Federal Register 2010, 2011, 2012, 2013

...implementation of sea lamprey control techniques alternative to lampricide...enhance alternative sea lamprey control techniques. The meeting is...cancelled due to inclement weather. Any member of public who...Lake Champlain Sea Lamprey Control Alternatives Workgroup,...

2010-12-29

2

76 FR 12129 - Lake Champlain Sea Lamprey Control Alternatives Workgroup  

Federal Register 2010, 2011, 2012, 2013

...implementation of sea lamprey control techniques alternative to lampricide...enhance alternative sea lamprey control techniques. The meeting is...cancelled due to inclement weather. Any member of the public...Lake Champlain Sea Lamprey Control Alternatives Workgroup,...

2011-03-04

3

Limnology of Lake Champlain.  

National Technical Information Service (NTIS)

This report presents an exhaustive compilation of existing physical, chemical, and biological data on Lake Champlain. As a reference document, the report assembles both published and unpublished information. Data presentation is through text tables, illus...

G. E. Myer G. K. Gruendling

1979-01-01

4

75 FR 54163 - Office of the Secretary: Renewal of the Lake Champlain Sea Lamprey Control Alternatives Workgroup  

Federal Register 2010, 2011, 2012, 2013

...Secretary through the Fish and Wildlife Service and Lake Champlain Fish and Wildlife Management Cooperative...projects; Facilitating coordinated research between Lake Champlain and the Great Lakes; and Development of requests for...

2010-09-03

5

33 CFR 117.797 - Lake Champlain.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 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...

2013-07-01

6

33 CFR 117.797 - Lake Champlain.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 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...

2009-07-01

7

33 CFR 117.797 - Lake Champlain.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 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...

2010-07-01

8

33 CFR 117.993 - Lake Champlain.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 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...

2009-07-01

9

33 CFR 117.993 - Lake Champlain.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 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...

2010-07-01

10

Materials Budgets of Lake Champlain.  

National Technical Information Service (NTIS)

The objectives of the report were to ascertain the general water quality status of the tributaries discharging into Lake Champlain and to estimate the materials input to the lake. Water samples were collected from about 40 tributaries during the period 19...

E. B. Henson M. Potash

1976-01-01

11

Limnology of Lake Champlain: 1965-1970.  

National Technical Information Service (NTIS)

This five year study assembled information on physical, chemical, and biological characteristics of Lake Champlain, Vermont, one of the largest and deepest lakes of the USA. The determinations included currents of the lake, water thermal and optical featu...

E. B. Henson M. Potash

1970-01-01

12

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

USGS Publications Warehouse

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

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

2011-01-01

13

75 FR 21990 - Safety Zone; Extended Debris Removal in the Lake Champlain Bridge Construction Zone (Between...  

Federal Register 2010, 2011, 2012, 2013

...surrounding the Lake Champlain Bridge construction zone between Chimney...of materials, performance, design, or operation; test methods...Removal in the Lake Champlain Bridge Construction Zone (between...either side of the Lake Champlain Bridge construction zone, marked...

2010-04-27

14

Shoreline Stabilization Handbook for Lake Champlain and Other Inland Lakes.  

National Technical Information Service (NTIS)

This handbook is for area residents and government officials who are working to create and maintain a landscape that complements Lake Champlains setting and ecology, while enhancing opportunities for the enjoyment of its natural and recreational features....

2004-01-01

15

75 FR 22228 - Regulated Navigation Area; Lake Champlain Bridge Construction Zone, NY and VT  

Federal Register 2010, 2011, 2012, 2013

...Transportation Company, Champlain Bridge Marina, Van Slooten Marina...of materials, performance, design, or operation; test methods...Navigation Area; Lake Champlain Bridge Construction, Crown Point...south of the Lake Champlain Bridge construction zone at Crown...

2010-04-28

16

33 CFR 110.136 - Lake Champlain, NY and VT.  

Code of Federal Regulations, 2010 CFR

...Waters 1 2010-07-01 2010-07-01 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....

2010-07-01

17

33 CFR 110.136 - Lake Champlain, NY and VT.  

Code of Federal Regulations, 2010 CFR

...Waters 1 2009-07-01 2009-07-01 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....

2009-07-01

18

33 CFR 110.136 - Lake Champlain, NY and VT.  

Code of Federal Regulations, 2013 CFR

...1 2013-07-01 2013-07-01 false Lake Champlain, NY and VT. 110.136 Section 110.136 Navigation and Navigable...REGULATIONS Anchorage Grounds § 110.136 Lake Champlain, NY and VT. (a) Burlington Harbor, Vt. (1) The...

2013-07-01

19

33 CFR 165.T01-0176 - Regulated Navigation Area; Lake Champlain Bridge Construction, Crown Point, New York and Chimney...  

Code of Federal Regulations, 2010 CFR

... Regulated Navigation Area; Lake Champlain Bridge Construction, Crown Point... Regulated Navigation Area; Lake Champlain Bridge Construction, Crown Point... All navigable waters on Lake Champlain 300 yards to the north and...

2010-07-01

20

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

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 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...

2010-07-01

21

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

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 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...

2009-07-01

22

Detrital ooids of Holocene age in glaciomarine Champlain Sea sediments, Gatineau, Quebec, Canada  

Microsoft Academic Search

Detrital ooids, from 0.1 to 0.5 mm diameter, almost completely dominate two 0.3 m thick layers between one and two metres depth at a site in clay-size-rich, isostatically uplifted, glaciomarine, Champlain Sea sediments north of Gatineau, Quebec. The ooids, composed of layers of tangentially oriented, platy particles, are physical aggregations of glacially ground, rock flour with the identical mineral suite

J. Kenneth Torrance; Reed Kirkpatrick

2004-01-01

23

The deposition of mercury in throughfall and litterfall in the lake champlain watershed: A short-term study  

NASA Astrophysics Data System (ADS)

As part of an ongoing study of the atmospheric deposition of Hg in the Lake Champlain watershed, event throughfall, event precipitation, ambient, green foliage, and litterfall samples were collected and analyzed for Hg from a mixed hardwood forest in Underhill Center, VT, for six weeks during the months of August and September 1994. During this time period, the volume-weighted mean Hg concentration in throughfall (12.0 8.5 ng ? -1) was higher than in precipitation (6.5 2.8 ng ? -1). In August and September 1994, the total deposition of Hg in throughfall was estimated to be 3.1 ?gm -2 (1.9 ?g m -2 in precipitation) to the deciduous hardwood forests in the Lake Champlain basin. The mean Hg concentration in litterfall (53.2 11.4 ng g -1) was significantly greater than the mean concentration in green foliage (34.2 +7.2 ng g -1), suggesting uptake of Hg from the atmosphere by foliage. Estimated annual litterfall deposition to the Lake Champlain basin was 13 ?g m -2. This study suggests that throughfall and litterfall play a significant role in the cycling and deposition of Hg in the Lake Champlain watershed.

Rea, Anne W.; Keeler, Gerald J.; Scherbatskoy, Timothy

24

Wetlands in the Lake Champlain Region of Vermont: Present and Future Threats to the Resource. Boundary Determination and Background Information for the EPA's Proposed Advanced Identification.  

National Technical Information Service (NTIS)

EPA Region 1 Wetlands Protections Section is planning an Advanced Identification Project for the Lake Champlain Region of Vermont. 'Advanced Identification' refers to the two authorities EPA can utilize under Section 404 of the Clean Water Act to protect ...

M. A. Borre

1988-01-01

25

The Allerd Younger Dryas Holocene sequence in the west-central Champlain Sea, eastern Ontario: a record of glacial, oceanographic, and climatic changes  

NASA Astrophysics Data System (ADS)

The aragonite mineralogy and geochemistry of the mollusc faunas preserved at Navan and Bearbrook, Ontario, serve as proxies of original seawater chemistry. The composite section spanning 12,980 10,980 cal yr BP includes the Younger Dryas (YD) paleoclimatic oscillation. Oxygen isotopes demonstrate the onset of cooling with the YD event, in addition to the lowering of marine values by the influx of isotopically light glacial meltwater from Lake Agassiz. Impact of cooling and dilution is reduced or eliminated with the start of the Holocene, when water temperatures and salinities for Champlain Sea (CS) seawater were 8 16 C and 27 34 ppt, respectively. Overall, oxygen isotope values deceased to -3.5% during the YD mainly due to freshening by glacial meltwater. Carbon isotopes confirm the rise in atmospheric CO2 concentration at the YD Holocene transition. Marine strontium isotope values for the Allerd YD earliest Holocene range from 0.709151 (16,210 cal yr BP) to 0.709145 (12,980 cal yr BP) and 0.709142 (10,950 cal yr BP). The oceanographic changes recorded for the CS are in agreement with the evolutionary phases of Lake Agassiz and deglaciation dynamics of the Laurentide Ice Sheet. The volume and direction of meltwater discharge from Lake Agassiz alternated between the Gulf of Mexico during the Allerd, via the Great Lakes through the CS to the North Atlantic during the YD, and back to the Gulf of Mexico during the early Holocene, but with diminished impact.

Brand, Uwe; McCarthy, Francine M. G.

2005-07-01

26

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

2013-02-26

27

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

28

Champlain MBA  

Microsoft Academic Search

\\u000a Champlains newly designed MBA exploits an experientially-based format built around: (1) leadership, communication, and career\\u000a management, (2) contextualized student experiences, (3) integration of multiple functional disciplines, and (4) deliberate\\u000a skill development in life-long learning.\\u000a \\u000a \\u000a Five lines of research informed the specification of Champlains MBA:\\u000a \\u000a \\u000a (1)\\u000a \\u000a \\u000a Action learning frameworks for work-based projects\\u000a \\u000a \\u000a \\u000a \\u000a (2)\\u000a \\u000a \\u000a Knowledge management frameworks for life-long learning\\u000a \\u000a \\u000a \\u000a \\u000a (3)\\u000a \\u000a \\u000a Reflective

Donald R. Haggerty; Victor J. Stone

29

Great Lakes Region Sea Grant  

NSDL National Science Digital Library

Site dedicated to the Great Lakes Sea Grant program. Information on GLSG priorities and initiatives. Topics of increased importance to the Great Lakes include fisheries and invasive species. Links to sites featuring publications and photos of Great Lakes storms and seiches and wildlife.

30

High-water marks from flooding in Lake Champlain from April through June 2011 and Tropical Storm Irene in August 2011 in Vermont  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the Federal Emergency Management Agency, identified high-water marks after two floods in Vermont during 2011. Following a snowy winter, new monthly precipitation records were set in Burlington, Vermont, in April and May 2011, causing extensive flooding from April through June. The spring 2011 flooding resulted in a new record for stage (103.27 feet, referenced to the National Geodetic Vertical Datum of 1929) at the Lake Champlain at Burlington, Vt., gaging station (04294500). During August 28 and 29, 2011, tropical storm Irene delivered rainfall totals of 3 to more than 7 inches throughout Vermont, which resulted in extensive flooding and new streamflow records at nine streamgaging stations. Four presidential declarations of disaster were made following the 2011 flood events in Vermont. Thirty-nine high-water marks were identified and flagged to mark the highest levels of Lake Champlain from the May 2011 flooding, and 1,138 high-water marks were identified and flagged along Vermont rivers after flooding from tropical storm Irene in August 2011. Seventy-four percent of the high-water marks that were flagged were later found and surveyed to the North American Vertical Datum of 1988.

Medalie, Laura; Olson, S. A.

2013-01-01

31

66 FR 33233 - Improved Methods for Ballast Water Treatment and Management and Lake Champlain Canal Barrier...  

Federal Register 2010, 2011, 2012, 2013

...present in U.S. waters, or with the...resources and the economies that depend...of 1990 (16 U.S.C. 4701...coastal and Great Lakes ecosystems...by ballast water discharge in...shipping, and the changes in modern...

2001-06-21

32

The Sea Lamprey in the Great Lakes  

Microsoft Academic Search

The sea lamprey was inadvertently introduced above Niagara Falls by the development of the Welland Canal between Lakes Ontario and Erie. A major population did not develop in Lake Erie but the species rapidly established itself as a highly significant predator in all three upper lakes. Its most obvious effect was the virtual extermination of the lake trout which had

A. H. Lawrie

1970-01-01

33

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.

34

Contingent rating method for measuring the benefits of water-quality improvements: development and application. [St. Albans Bay, Lake Champlain  

Microsoft Academic Search

A new contigent valuation method was developed and tested for estimating the benefits from improving the water quality of a lake or stream. The need for such a method arises because of the public-goods nature of water quality. The contigent rating method is a technique that uses utility information to indirectly measure the benefits from an improvement in water quality

1983-01-01

35

The Sea Lamprey in Lake Erie: a Case History  

Microsoft Academic Search

Sea lampreys (Petromyzon marinus), first reported in Lake Erie in 1921, emigrated from Lake Ontario via the Welland Canal. It was not until the advent of pollution abatement, stream rehabilitation, and salmonid enhancement programs that sea lampreys proliferated. The Great Lakes Fishery Commission (GLFC), in co-operation with state, provincial, and federal fisheries agencies, implemented an integrated sea lamprey management (IMSL)

W. Paul Sullivan; Gavin C. Christie; Floyd C. Cornelius; Michael F. Fodale; David A. Johnson; Joseph F. Koonce; Geraldine L. Larson; Rodney B. McDonald; Katherine M. Mullett; Charles K. Murray; Phillip A. Ryan

2003-01-01

36

Lethality of Sea Lamprey Parasitism on Lake Sturgeon  

Microsoft Academic Search

Parasitism by sea lampreys Petromyzon marinus may contribute to the delayed recovery of imperiled populations of lake sturgeon Acipenser fulvescens in the Great Lakes. Our study objectives were to examine the survival, growth, and condition of four size-classes of lake sturgeon following a single sea lamprey attack. Lake sturgeon from one of four size-groups (I: 470-570 mm fork length; II:

Holly K. Patrick; Trent M. Sutton; William D. Swink

2009-01-01

37

Fisheries Education: From the Great Lakes to the Sea.  

ERIC Educational Resources Information Center

|Described are investigations related to fisheries education developed by the Ohio Sea Grant Education Office as a part of a series of Oceanic Education Activities for Great Lake Schools. The investigations discussed are "Yellow Perch in Lake Erie," which concerns fisheries management, and "It's Everyone's Sea: Or Is It," which focuses on fishing

Fortner, Rosanne; Mayer, Victor J.

1980-01-01

38

Concentration, flux, and the analysis of trends of total and dissolved phosphorus, total nitrogen, and chloride in 18 tributaries to Lake Champlain, Vermont and New York, 19902011  

USGS Publications Warehouse

Annual concentration, flux, and yield for total phosphorus, dissolved phosphorus, total nitrogen, and chloride for 18 tributaries to Lake Champlain were estimated for 1990 through 2011 using a weighted regression method based on time, tributary streamflows (discharges), and seasonal factors. The weighted regression method generated two series of daily estimates of flux and concentration during the period of record: one based on observed discharges and a second based on a flow-normalization procedure that removes random variation due to year-to-year climate-driven effects. The flownormalized estimate for a given date is similar to an average estimate of concentration or flux that would be made if all of the observed discharges for that date were equally likely to have occurred. The flux bias statistic showed that 68 of the 72 flux regression models were minimally biased. Temporal trends in the concentrations and fluxes were determined by calculating percent changes in flow-normalized annual fluxes for the full period of analysis (1990 through 2010) and for the decades 19902000 and 20002010. Basinwide, flow-normalized total phosphorus flux decreased by 42 metric tons per year (t/yr) between 1990 and 2010. This net result reflects a basinwide decrease in flux of 21 metric tons (t) between 1990 and 2000, followed by a decrease of 20 t between 2000 and 2010; both results were largely influenced by flux patterns in the large tributaries on the eastern side of the basin. A comparison of results for total phosphorus for the two separate decades of analysis found that more tributaries had decreasing concentrations and flux rates in the second decade than the first. An overall reduction in dissolved phosphorus flux of 0.7 t/yr was seen in the Lake Champlain Basin during the full period of analysis. That very small net change in flux reflects substantial reductions between 1990 and 2000 from eastern tributaries, especially in Otter Creek and the LaPlatte and Winooski Rivers that largely were offset by increases in the Missisquoi and Saranac Rivers in the second decade (between 2000 and 2010). The number of tributaries that had increases in dissolved phosphorus concentrations stayed constant at 13 or 14 during the period of analysis. Total nitrogen concentration and flux for most of the monitored tributaries in the Lake Champlain Basin have decreased since 1990. Between 1990 and 2010, flow-normalized total nitrogen flux decreased by 386 t/yr, which reflects an increase of 440 t/yr between 1990 and 2000 and a decrease of 826 t/yr between 2000 and 2010. All individual tributaries except the Winooski River had decreases in total nitrogen concentration and flux between 2000 and 2010. The decrease in total nitrogen flux over the period of record could be related to the decrease in nitrogen from atmospheric deposition observed in Vermont or to concurrent benefits realized from the implementation of agricultural best-management practices in the Lake Champlain Basin that were designed primarily to reduce phosphorus runoff. For chloride, large increases in flow-normalized concentrations and flux between 1990 and 2000 for 17 of the 18 tributaries diminished to small increases or decreases between 2000 and 2010. Between 1990 and 2010, flow-normalized flux increased by 32,225 t/yr, 78 percent of which (25,163 t) was realized during the first decade, from 1990 through 2000. The five tributaries that had decreasing concentration and flux of chloride between 2000 and 2010 were all on the eastern side of Lake Champlain, possibly related to reductions since 1999 in winter road salt application in Vermont. Positive correlations of phosphorus flux and changes in phosphorus concentration and flux in tributaries with phosphorus inputs to basins from point sources, suggest that point sources have an effect on stream phosphorus chemistry. Several measures of changes in agricultural statistics, such as agricultural land use, acres of land in farms, acres of cropland, and acres of corn for grain or seed, are positively correlated with changes in phosp

Medalie, Laura

2013-01-01

39

Ra and Th adsorption coefficients in lakesLake Kinneret (Sea of Galilee) natural experiment  

Microsoft Academic Search

The adsorption rate constants of Ra and Th were estimated from empirical data from a freshwater lake and its feeding saline springs. We utilized the unique setting of Lake Kinneret (Sea of Galilee, northern Israel) in which most of the Ra and Th nuclides are introduced into the lake by saline springs with high 226Ra activities and a high 224Ra\\/228Ra

Boaz Lazar; Yishai Weinstein; Adina Paytan; Einat Magal; Debbie Bruce; Yehoshua Kolodny

2008-01-01

40

Lake Trout, Sea Lampreys, and Overfishing in the Upper Great Lakes: A Review and Reanalysis  

Microsoft Academic Search

To assess the role of commercial fishing in the destruction of lake trout Salvelinus namaycush in Lakes Huron, Michigan, and Superior in the 1940s and 1950s, we reviewed the literature and analyzed catch and effort data for U.S. waters by regression analysis. There is abundant evidence of the effect of the sea lamprey Petromyzon marinus in the destruction of lake

Daniel W. Coble; Richard E. Bruesewitz; Thomas W. Fratt; Jeffrey W. Scheirer

1990-01-01

41

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

42

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

Microsoft Academic Search

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 (46C) and are more abundant than lean lake trout (Salvelinus namaycush) which occupy temperatures between 8 and 12C during summer thermal stratification. Using

Eric K. Moody; Brian C. Weidel; Tyler D. Ahrenstorff; William P. Mattes; James F. Kitchell

2011-01-01

43

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

44

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

45

Groundwater-Lake Interaction in the Dead Sea Area  

NASA Astrophysics Data System (ADS)

The Dead Sea hypersaline water system is unique in terms of its unusual geochemical composition, rapid lake level changes and water composition of the brines discharging along its shoreline. The Dead Sea can be used as a natural lab for studying groundwater-seawater interaction and saline water hydrological circulation along the aquifer-sea boundary. It provides an opportunity to follow the geochemical processes along a flow path from the lake into the aquifer and back into the lake. The lake level has been dropping since the 1960's due to human interference in its water budget, reaching a rate of 1 m/yr in recent years. Saline water circulation in coastal aquifers may be a major process that governs trace element mass balances in coastal areas. This study uses radium isotopes in order to quantify the lake water circulation in the Dead Sea aquifer. There are four naturally-occurring radium isotopes, with half-lives ranging from 3.7 days to 1600 years which are chain products of uranium and thorium isotopes. Radium isotopes are usually enriched in saline groundwater and therefore are good candidates for estimating seawater or hypersaline lake water circulation in the aquifer. Compared to most natural water bodies, the Dead Sea is extremely enriched in radium and barium, where both 226Ra and 228Ra activities and Ba concentration (145, 1-2 dpm/L and 5 mg/L, respectively) are 2-3 orders of magnitude higher than in ocean water, whereas the salinity of the Dead Sea is only 10 times higher. Circulated Dead Sea water in the aquifer contains decreased concentrations of 226Ra (60 dpm/L), Ba (1.5 mg/L), Sr (300 relative to 340 mg/L in the Dead Sea) and Sulfate (250 relative to 392 mg/L). We suggest that the low 226Ra and Ba concentrations are due to precipitation of barite and celestine from the supersaturated Dead Sea water on entering the aquifer. 228Ra and the shorter-lived 224Ra and 223Ra, which have much lower activities in the Dead Sea (up to 1.8, 3 and 0.8 dpm/L, respectively), are enriched in the circulated Dead Sea water (up to 25, 100 and 30 dpm/L, respectively) due to recoil and desorption. This implies that the circulation of Dead Sea water in the aquifer removes 226Ra and contributes 228Ra, 223Ra and 224Ra to the lake. Therefore, a major source with relatively high 228Ra/226Ra ratios is added to the Dead Sea mass balance. Following a flow path of saline water from the Dead Sea inland, barium and 226Ra decrease gradually and 228Ra increases gradually. This provides a method for calculating the DS mass balance, groundwater age or velocity and the rate of barite and celestine precipitation. 228Ra ages are around 2 and 13 yrs at 10 and 80 m from the shore inland, respectively. With this velocity (5-6 m/yr), the first order precipitation rate constant is 0.23 1/yr. Based on 226Ra and 228Ra mass balances in the Dead Sea, the calculated amount of Dead Sea water circulation is 200-300 million m3/yr, which is of the same order of magnitude as all other known Dead Sea water sources at present (160-340 million m3/yr) and therefore is a significant component in the Dead Sea mass balance.

Kiro, Y.; Weinstein, Y.; Starinsky, A.; Yechieli, Y.

2011-12-01

46

Gonadal Variation in Great Lakes Sea Lamprey, Petromyzon marinus, Larvae  

Microsoft Academic Search

The observation of atypical gonads in land-locked sea lamprey larvae from several streams tributary to the Great Lakes led to this descriptive study on typical male and female gonads, as well as atypical gonads. Typical male and female gonads examined in the present study have similar characteristics to those observed in the past; however, larvae with atypical gonads have some

Beverly J. Wicks; Leslie A. Barker; Bruce J. Morrison; William H. Beamish

1998-01-01

47

Growth of lake trout in Lake Superior before the maximum abundance of sea lampreys  

USGS Publications Warehouse

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 and 9th years the increments increased from 2.6 to 3.5 inches. Growth was calculated from a curvilinear body-scale relation. Intraseasonal growth in length extended from late April until well after October; most growth was in late summer and fall. The younger fish started growth earlier, and some mature fish did not increase in length until after the October spawning. Lake trout reached the minimum legal weight (1.5 pounds) in the 7th year of life and the average size taken in the commercial fishery (about 3 pounds) in the 8th year. The annual increase in weight in the 8th year of life was over 64%. Fish used in this study grew more slowly than those from Lakes Michigan and Huron taken during the period when sea lamprey abundance was increasing, but at about the same rate as lake trout of Lake Michigan before the sea lamprey appeared.

Rahrer, Jerold F.

1967-01-01

48

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

49

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

50

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

2009-08-04

51

Evidence that lake trout served as a buffer against sea lamprey predation on burbot in Lake Erie  

USGS Publications Warehouse

The population of burbot Lota lota in Lake Erie recovered during 1986-2003, mainly because of the control of sea lamprey Petromyzon marinus, which began in 1986, Burbot populations continued to grow during 1996-1998, when sea lamprey control was substantially reduced. We calculated mortality parameters for burbot in Lake Erie by estimating age at capture for 2,793 burbot caught in annual gill-net surveys of eastern Lake Erie from 1994 to 2003. Based on catch-curve analysis, annual mortality in Lake Erie during 1994-2003 was estimated as 33%. Annual mortality of the 1992 year-class of burbot was estimated as 30%. The mortality of burbot during the years of reduced sea lamprey control was not different from that during the 3 years preceding reduced control and was significantly lower than that during the entire portion of the time series in which full sea lamprey control was conducted. These results suggest that the reduction in sea lamprey control did not lead to increased burbot mortality. The catch per gill-net lift of large burbot (total length > 600 mm), the size preferred by sea lampreys, was lower than that of adult lake trout Salvelinus namaycush (age 5 and older; total length > 700 mm) before lampricide application was reduced. Although adult lake trout populations declined, the abundance of large burbot did not change during the period of reduced lampricide application. These results support a hypothesis that a healthy population of adult lake trout can serve as a buffer species, acting to reduce predation of burbot by sea lampreys when sea lamprey populations increase. Burbot attained sexual maturity at a relatively early age (3 or 4 years) and a total length (approximately 500 mm) that was smaller than the preferred prey size for sea lampreys. These characteristics and the buffering effect of the lake trout population enabled growth of the burbot population during the brief period when lamprey control was reduced.

Stapanian, M. A.; Madenjian, C. P.

2007-01-01

52

33 CFR 117.993 - Lake Champlain.  

Code of Federal Regulations, 2013 CFR

...number posted at the bridge. (c) The draw of the New England Central Railroad Bridge across Missiquoi Bay, mile...3) The draw may be operated either remotely by the New England Central Railroad train dispatcher located at St....

2013-07-01

53

Transient salt transport modeling of shallow brine beneath a freshwater lake, the Sea of Galilee, Israel  

NASA Astrophysics Data System (ADS)

During a lake highstand phase in the late Pleistocene the former saline Lake Lisan covered the topographic depression of Kinarot Basin currently occupied by the freshwater lake, Sea of Galilee. It was hypothesized that during this period, the dense saline waters of Lake Lisan percolated into the sediment. The recession of the saline lake from the basin and the rapid formation of a freshwater lake triggered solute transport from the sediment into the lake. A one-dimensional numerical model of solute transport that considers sediment compaction was developed to simulate chloride transport from the sediment into the lake. Simulation results were compared with measured chloride concentration profiles in sediment cores. On the basis of a sensitivity analysis, results are in agreement with the hypothesis that Lake Lisan solutes are currently discharged into the Sea of Galilee. The calculated upward water velocity in the sediment ranges between 9 and 22 mm yr-1.

Hurwitz, Shaul; Lyakhovsky, Vladimir; Gvirtzman, Haim

2000-01-01

54

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

55

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

56

Estimating Lake-wide Abundance of Spawning-phase Sea Lampreys ( Petromyzon marinus) in the Great Lakes: Extrapolating from Sampled Streams Using Regression Models  

Microsoft Academic Search

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.

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

2003-01-01

57

Defining Economic Injury Levels for Sea Lamprey Control in the Great Lakes Basin  

Microsoft Academic Search

We estimated economic injury levels (EILs) and associated optimal control budgets for sea lamprey Petromyzon marinus for each of the Great Lakes using common assumptions and consistent methods. The lake-specific EILs are defined as equilibrium sea lamprey abundances below which incremental increases in control expenditures do not pay for themselves in terms of benefits (in the form of increased harvest

Brian J. Irwin; Weihai Liu; James R. Bence; Michael L. Jones

2012-01-01

58

Effects of Improved Water Quality and Stream Treatment Rotation on Sea Lamprey Abundance: Implications for Lake Trout Rehabilitation in the Great Lakes  

Microsoft Academic Search

Efforts over the past 25 years to improve water quality in the Great Lakes basin may be counteracting progress toward lake trout rehabilitation that has been made possible by sea lamprey control. Improved water quality in streams has been linked to increased amounts of suitable sea lamprey spawning and ammocoete habitat leading to increased sea lamprey production. To assess the

C. Paola Ferreri; William W. Taylor; Joseph F. Koonce

1995-01-01

59

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

60

Movement of parasitic-phase sea lampreys in Lakes Huron and Michigan  

USGS Publications Warehouse

A program of tagging was carrie dout in the waters of northern Lake Huron during the fall and winter of 1951-52 in order to supplement the small amount of information available on movement of sea lampreys during their parasitic phase. A total of 219 parasitic-phase sea lampreys were tagged and released at three localities. Of this number 38 or 17.2 percent were recovered. One tag was recovered near North Manitou Island, Lake Michigan. The remaining 37 were take in Lake Huron or in streams tributary to that lake. The dispersal of tagged lampreys throughout Lake Huron was wide. Five marked individuals were taken in the southern part of the lake over 150 miles from the point of tagging; 4 of these 5 were captured in Canadian waters. The marked lampreys exhibited no distinct pattern of migration other than a tendency toward a general southeasterly movement in Lake Huron.

Smith, Bernard R.; Elliott, Oliver R.

1953-01-01

61

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

62

Development and validation of a regional coupled atmosphere lake model for the Caspian Sea Basin  

NASA Astrophysics Data System (ADS)

We present a validation analysis of a regional climate model coupled to a distributed one dimensional (1D) lake model for the Caspian Sea Basin. Two model grid spacings are tested, 50 and 20 km, the simulation period is 1989-2008 and the lateral boundary conditions are from the ERA-Interim reanalysis of observations. The model is validated against atmospheric as well as lake variables. The model performance in reproducing precipitation and temperature mean seasonal climatology, seasonal cycles and interannual variability is generally good, with the model results being mostly within the observational uncertainty range. The model appears to overestimate cloudiness and underestimate surface radiation, although a large observational uncertainty is found in these variables. The 1D distributed lake model (run at each grid point of the lake area) reproduces the observed lake-average sea surface temperature (SST), although differences compared to observations are found in the spatial structure of the SST, most likely as a result of the absence of 3 dimensional lake water circulations. The evolution of lake ice cover and near surface wind over the lake area is also reproduced by the model reasonably well. Improvements resulting from the increase of resolution from 50 to 20 km are most significant in the lake model. Overall the performance of the coupled regional climate1D lake model system appears to be of sufficient quality for application to climate change scenario simulations over the Caspian Sea Basin.

Turuncoglu, Ufuk Utku; Elguindi, Nellie; Giorgi, Filippo; Fournier, Nicolas; Giuliani, Graziano

2013-10-01

63

Development and validation of a regional coupled atmosphere lake model for the Caspian Sea Basin  

NASA Astrophysics Data System (ADS)

We present a validation analysis of a regional climate model coupled to a distributed one dimensional (1D) lake model for the Caspian Sea Basin. Two model grid spacings are tested, 50 and 20 km, the simulation period is 1989-2008 and the lateral boundary conditions are from the ERA-Interim reanalysis of observations. The model is validated against atmospheric as well as lake variables. The model performance in reproducing precipitation and temperature mean seasonal climatology, seasonal cycles and interannual variability is generally good, with the model results being mostly within the observational uncertainty range. The model appears to overestimate cloudiness and underestimate surface radiation, although a large observational uncertainty is found in these variables. The 1D distributed lake model (run at each grid point of the lake area) reproduces the observed lake-average sea surface temperature (SST), although differences compared to observations are found in the spatial structure of the SST, most likely as a result of the absence of 3 dimensional lake water circulations. The evolution of lake ice cover and near surface wind over the lake area is also reproduced by the model reasonably well. Improvements resulting from the increase of resolution from 50 to 20 km are most significant in the lake model. Overall the performance of the coupled regional climate1D lake model system appears to be of sufficient quality for application to climate change scenario simulations over the Caspian Sea Basin.

Turuncoglu, Ufuk Utku; Elguindi, Nellie; Giorgi, Filippo; Fournier, Nicolas; Giuliani, Graziano

2012-12-01

64

Long-Term Alterations to the Varna-Beloslav Lake Complex due to Human Activities (Bulgarian Black Sea Coast)  

Microsoft Academic Search

There are several larger lakes at the 412 km long Bulgarian Black Sea coastline, as each distinguishes with a specific hydrological regime and parameters. The deepest and the largest is the Varna Lake, located west from the Bay of Varna at the North Bulgarian coast. The lake is a firth formation at the river valley under a rising sea level

Hristo Stanchev; Veselin Peychev; Atanas Palazov; Margarita Stancheva

2010-01-01

65

Genetic Identification of Sea Lamprey, 'Petromyzon marinus', Populations from the Lake Superior Basin.  

National Technical Information Service (NTIS)

Sea lamprey (Petromyzon marinus) ammocoetes collected from eighteen locations within Lake Superior were electrophoretically analyzed for genetic variability at 25 enzyme loci. Enzyme expression did not vary between life states (ammocete vs. adult) or coll...

C. C. Krueger G. R. Spangler

1980-01-01

66

Taihu Lake, lower Yangtze drainage basin: evolution, sedimentation rate and the sea level  

NASA Astrophysics Data System (ADS)

The present study focuses on two Holocene sediment boreholes in Taihu Lake, sunk to examine the lake sediment including sedimentary texture and structure, microfossils, magnetic susceptibility and radiocarbon-dated Holocene stratigraphy. Results demonstrate that the early Taihu Lake area consisted primarily of West Taihu Lake depression and a low floodplain in the East Taihu Lake area. No hydraulic connection existed between the two sectors during the early Holocene when sea level stood at lower level. Core sediments, microfossil and magnetic evidence records that West Taihu Lake began to be inundated by brackish water prior to 6000 years ago, while East Taihu Lake still remained a freshwater setting. After 6000 B.P., a further rise in freshwater table in response to sea-level fluctuation progressively drowned the entire lake, coalescing the two parts after 4600-3500 B.P. Our coring revealed that the lacustrine sediment began to form in West Taihu Lake as early as 11,000 years ago, while it happened much later (only after 5700 B.P.) to form in East Taihu Lake. High sedimentation rates (0.42-0.35 mm/year) in lacustrine deposits of West Taihu Lake occurred between ~11,000 and 5000 B.P. In contrast, the high sedimentation rates (1.54 mm/year) in East Taihu Lake occurred only within a very short time period, from ~6500 to 5500 B.P. Since then, sedimentation rates have decelerated to a very low value (<0.10 mm/year) in both West and East Taihu Lakes. The low sedimentation rate of West and East Taihu Lake of the middle and late Holocene explains the deceleration of the sea-level rising after 5500 B.P. and the rapid coastal progradation seaward.

Wang, Jian; Chen, Xia; Zhu, Xiao-hua; Liu, Jin-ling; Chang, William Y. B.

2001-11-01

67

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

68

Evidence that sea lamprey control led to recovery of the burbot population in Lake Erie  

USGS Publications Warehouse

Between 1987 and 2003, the abundance of burbot Lota lota in eastern Lake Erie increased significantly, especially in Ontario waters. We considered four hypotheses to explain this increase: (1) reduced competition with lake trout Salvelinus namaycush, the other major coldwater piscivore in Lake Erie; (2) increased abundance of the two main prey species, rainbow smelt Osmerus mordax and round goby Neogobius melanostomus; (3) reduced interference with burbot reproduction by alewives Alosa pseudoharengus; and (4) reduced predation by sea lampreys Petromyzon marinus on burbot. Species abundance data did not support the first three hypotheses. Our results suggested that the apparent recovery of the burbot population of Lake Erie was driven by effective sea lamprey control. Sea lamprey predation appeared to be the common factor affecting burbot abundance in Lakes Michigan, Huron, Erie, and Ontario. In addition, relatively high alewife density probably depressed burbot abundance in Lakes Ontario and Michigan. We propose that a healthy adult lake trout population may augment burbot recovery in some lakes by serving as a buffer against sea lamprey predation and will not negatively impact burbot through competition. ?? Copyright by the American Fisheries Society 2006.

Stapanian, M. A.; Madenjian, C. P.; Witzel, L. D.

2006-01-01

69

Investigating the Great Lakes Environment, Unit One: The Sea Lamprey Story.  

ERIC Educational Resources Information Center

Presented are 11 middle school activities dealing with the sea lamprey and its impact upon the Great Lakes. Included are background information, lesson outlines, references, masters for student worksheets, a wall map, game boards, and two filmstrip-tape units. Using these materials students can learn ecological concepts and some Great Lakes

Lin, Leslie; And Others

70

History of and Advances in Barriers as an Alternative Method to Suppress Sea Lampreys in the Great Lakes  

Microsoft Academic Search

The Great Lakes Fishery Commission (GLFC) continues to seek additional methods of sea lamprey (Petromyzon marinus) control to reduce reliance on chemical lampricides (pesticides) and increase the efficiency of the program. Barriers to migrating sea lampreys in tributaries can significantly reduce the spawning potential of sea lamprey in the Great Lakes. These barriers can be any natural or man-made structure

Dennis S. Lavis; Andrew Hallett; Ellie M. Koon; Tom C. McAuley

2003-01-01

71

Compensatory Mechanisms in Great Lakes Sea Lamprey Populations: Implications for Alternative Control Strategies  

Microsoft Academic Search

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)

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

2003-01-01

72

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

National Technical Information Service (NTIS)

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 th...

J. R. Bence R. A. Bergstedt G. C. Christie P. A. Cochran M. P. Ebener J. F. Koonce M. A. Rutter W. D. Swink

2002-01-01

73

An Improved Method to Estimate Sea Lamprey Wounding Rate on Hosts with Application to Lake Trout in Lake Huron  

Microsoft Academic Search

To better estimate wounding rates on hosts of sea lamprey (Petromyzon marinus) in the Great Lakes, methods were developed to fit a logistic model for the mean number of wounds per host as a function of host length. These methods were applied to the number of wounds (the sum of type A-I to A-III marks on hosts collected in spring)

Michael A. Rutter; James R. Bence

2003-01-01

74

Effect of size on lake trout survival after a single sea lamprey attack  

USGS Publications Warehouse

When lake trout Salvelinus namaycush were subjected to a single attack by a sea lamprey Petromyzon marinus in laboratory tests in 1986, percentage mortality was significantly higher in small fish (64%; 469-557 mm; N = 67) than in medium (44%; 559-643 mm; N = 45) or large fish (43%; 660-799 mm; N = 47). Additional studies conducted in 1987 with 55 medium (559-650 mm) and 52 large (660-825 mm) lake trout confirmed that there was no difference in mortality between the two larger size-groups. Mortality declined in lake trout over 559 mm, but was still greater than 43%. This level of mortality and the sea lampreys' apparently active selection of larger fish indicated that, contrary to previously published opinions, large size in lake trout (up to ?800 mm in length) might not allow better survival from single sea lamprey attacks.

Swink, William D.

1990-01-01

75

A numerical study on the influence of fractured regions on lake\\/groundwater interaction; the Lake Kinneret (Sea of Galilee) case  

Microsoft Academic Search

Increased lake salinity is a growing problem in arid and semi-arid regions. Operational management, which is based on a reliable hydrological understanding, has the potential to reduce the lake salinity. This is the case of the salinity in Lake Kinneret (Sea of Galilee), where saline water flows into the lake through on-shore and off-shore springs. Here, we present a time-dependent

Hila Abbo; Uri Shavit; Doron Markel; Alon Rimmer

2003-01-01

76

Lethality of sea lamprey attacks on lake trout in relation to location on the body surface  

USGS Publications Warehouse

We compared the locations of healed attack marks of the sea lamprey Petromyzon marinus on live lake trout Salvelinus namaycush with those of unhealed attack marks on dead lake trout to determine if the lethality of a sea lamprey attack was related to attack location. Lake trout were collected from Lake Ontario, live fish with gill nets in September 1985 and dead fish with trawls in October 19831986. Attack location was characterized by the percent distances from snout to tail and from the ventral to the dorsal midline. Kolmogorov-Smirnov two-sample tests did not detect significant differences in the distribution of attack location along either the anteroposterior axis or the dorsoventral axis. When attack locations were grouped into six anatomical regions historically used to record sea lamprey attacks, dead fish did not exhibit a significantly higher proportion of attacks in the more anterior regions. Even if the differences in attack location on live and dead fish were significant, they were too small to imply substantial spatial differences in attack lethality that should be accounted for when modeling the effects of sea lampreys feeding on lake trout. We suggest that the tendency for sea lamprey attacks to occur on the anterior half of the fish is related to the lower amplitude of lateral body movement there during swimming and thus the lower likelihood of being dislodged.

Bergstedt, Roger A.; Schneider, Clifford P.; O'Gorman, Robert

2001-01-01

77

Paleolimnological and geochronological studies of salt lakes of Crimea, the Black Sea area  

NASA Astrophysics Data System (ADS)

1. Crimea is one of the few places in the northern Black Sea region with mineral lakes with sediments that can give information about paleoclimate and environmental changes over a long time period. All of these lakes are shallow (c. 1-1.5 m), saline of marine origin (former marine bays and lagoons), the emergence of which took place in historical' time (c. 5000 yrs ago). 2. The thickness of sediments is reaching up to 20-25 m. The recovery of long sediment sequences permits comparative study of the complex interactions among humans, climate and environment in the Crimea. Moreover, it provides an opportunity to establish a direct chronological link between major ethno-historical and economic processes on the one hand and climatic changes such as wet-dry circles that affected the whole area on the other. 3. Two lake sediment sequences have been recovered from the Crimean Peninsula ((Lake Saki (45 06',8N; 33 33',2E, water depth ca 0.8 m, recovered sediments 4.2 m) and Lake Dzharylgach(45 34',7N; 32 51',7E, water depth ca 0.8 m, recovered sediments 4.15 m)) during the field campaign 2005, as part of the Joint Danish-Russian-Ukraine project called "Northern Black Sea in the 1st millennium BC: human history and climate changes". In 2006, a detailed examination of the cores was carried out by the team members from the Institute of Limnology, RAS, St Petersburg, the National Taras Shevchenko University of Kyiv, and the Institute of Physics of the Earth, NASU, Kiev. The detailed examination of the cores, which includes varve counting, lithostratigraphy, geochemistry, pollen, diatom and ostracods analyses is presently being carried out. The AMS 14C dating is being processed by the Radiocarbon Laboratory, Institute of Physics and Astronomy. 4. In the both studied lakes, marine sediments overlain by mineralized lake sediments were recovered. The oldest dates from marine sediment from both studied sequences are 5500-5370 cal BP (L.Saki) and 7200-7050 cal BP (L.Dzharylgach). 5. The transition from the open sea environment conditions to the lagoon and the closed mineralized lakes is dated ca 5610-5340 calendar yr BP for the Saki Lake and 5590-5350 calendar yr BP for the Dzharylgach Lake. A complete isolation of the Saki Lake from the Black Sea occurred ca. 5200 calendar yr BP and isolation of the Dzharylgach Lake occurred around 4700 calendar yr BP, 500 years later then Lake Saki, during the transgression phase of the Black Sea. 6. The analysis of ostracods of the Dzharylgach Lake revealed a significant change in their associations along the sediment sequence that corresponded with water-level changes and a connection with the Black Sea. This allowed outlining the lake's main development stages which resulted from the changing paleogeographical situation, climate, and, as a consequence, ecological conditions of the basin. 7. The ensuing glacio-eustatic New Black Sea transgression resulted in a gradual rise of sea level, which reached its maximum of 2.0-2.5 m at 5800-5600 BP. At this stage, sea water penetrated into the river valleys and formed the estuaries which eventually developed into the present-day limans. 8. Pollen diagrams illustrating the region's basic variations in vegetation and climate have been produced for both sediment sequences. 9. New results of our multi-proxy paleolimnological studies which is being carried out in the Crimean Peninsula will be presented during the Conference.

Subetto, D. A.; Sapelko, T. V.; Kuznetsov, D. D.; Ludikova, A. V.; Gerasimenko, N.; Stolba, V.; Bakhmutov, V.

2009-04-01

78

Diffusive flux of selenium between lake sediment and overlying water: Assessing restoration alternatives for the Salton Sea  

Microsoft Academic Search

Elevated concentrations of selenium are a concern for humans and wildlife at the Salton Sea, a large salt lake in the desert of southeastern California. As the lake is highly eutrophic and has become too saline for most fish, various restoration alternatives have been proposed. These would alter the water quality, volume, depth, and surface area of the Salton Sea

Earl R. Byron; Harry M. Ohlendorf

2007-01-01

79

Spatial Distribution of Mercury and Organochlorine Contaminants in Great Lakes Sea Lamprey ( Petromyzon marinus)  

Microsoft Academic Search

Adult sea lamprey (Petromyzon marinus) were collected during their spawning migration in streams entering each of the Great Lakes, except Lake Michigan. Skinless muscle tissue samples were analyzed for a range of organochlorine contaminants including p,p-DDE, total PCB, toxaphene, and mercury. Concentrations of p,p-DDE and PCBs were above the detection limit of 0.002 ?g\\/g in all samples. Levels of total

D. Cameron MacEachen; Ronald W. Russell; D. Michael Whittle

2000-01-01

80

An Economic Injury Level Approach to Establishing the Intensity of Sea Lamprey Control in the Great Lakes  

Microsoft Academic Search

Tightening budgetary constraints have forced the Great Lakes Fishery Commission to reevaluate the effectiveness of its program to control sea lamprey Petromyzon marinus in the Great Lakes. One rational option requires setting target levels of control for each of the Great Lakes. This paper is an analysis of an economic injury level approach to setting a target level of control

Joseph F. Koonce; Randy L. Eshenroder; Gavin C. Christie

1993-01-01

81

Seasonal Patterns in Growth, Blood Consumption, and Effects on Hosts by Parasitic-Phase Sea Lampreys in the Great Lakes: An Individual-Based Model Approach  

Microsoft Academic Search

An individual-based model (IBM) was developed for sea lamprey (Petromyzon marinus) populations in the Laurentian Great Lakes. The IBM was then calibrated to observed growth, by season, for sea lampreys in northern Lake Huron under two different water temperature regimes: a regime experienced by Seneca-strain lake trout (Salvelinus namaycush) and a regime experienced by Marquettestrain lake trout. Modeling results indicated

Charles P. Madenjian; Philip A. Cochran; Roger A. Bergstedt

2003-01-01

82

Alluvial deposition and lake-level fluctuations forced by Late Quaternary climate change: the Dead Sea case example  

Microsoft Academic Search

Based on geomorphic observations, we discuss lake-level fluctuations, alluvial deposition and river entrenchment in the Dead SeaWadi Araba area. The bulk of alluvium in the northern Wadi Araba was probably deposited before the Lisan period of lake transgression that started at about 70 kyears B.P. The lake reached a maximum elevation about 150 m below sea level (b.s.l.), possibly around

Y. Klinger; J. P. Avouac; D. Bourles; N. Tisnerat

2003-01-01

83

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

84

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

85

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

86

Estimating parasitic sea lamprey abundance in Lake Huron from heterogeneous data sources  

USGS Publications Warehouse

The Great Lakes Fishery Commission uses time series of transformer, parasitic, and spawning population estimates to evaluate the effectiveness of its sea lamprey (Petromyzon marinus) control program. This study used an inverse variance weighting method to integrate Lake Huron sea lamprey population estimates derived from two estimation procedures: 1) prediction of the lake-wide spawning population from a regression model based on stream size and, 2) whole-lake mark and recapture estimates. In addition, we used a re-sampling procedure to evaluate the effect of trading off sampling effort between the regression and mark-recapture models. Population estimates derived from the regression model ranged from 132,000 to 377,000 while mark-recapture estimates of marked recently metamorphosed juveniles and parasitic sea lampreys ranged from 536,000 to 634,000 and 484,000 to 1,608,000, respectively. The precision of the estimates varied greatly among estimation procedures and years. The integrated estimate of the mark-recapture and spawner regression procedures ranged from 252,000 to 702,000 transformers. The re-sampling procedure indicated that the regression model is more sensitive to reduction in sampling effort than the mark-re capture model. Reliance on either the regression or mark-recapture model alone could produce misleading estimates of abundance of sea lampreys and the effect of the control program on sea lamprey abundance. These analyses indicate that the precision of the lake-wide population estimate can be maximized by re-allocating sampling effort from marking sea lampreys to trapping additional streams.

Young, R. J.; Jones, M. L.; Bence, J. R.; McDonald, R. B.; Mullett, K. M.; Bergstedt, R. A.

2003-01-01

87

Estimating parasitic sea lamprey abundance in Lake Huron from heterogenous data sources  

USGS Publications Warehouse

The Great Lakes Fishery Commission uses time series of transformer, parasitic, and spawning population estimates to evaluate the effectiveness of its sea lamprey (Petromyzon marinus) control program. This study used an inverse variance weighting method to integrate Lake Huron sea lamprey population estimates derived from two estimation procedures: 1) prediction of the lake-wide spawning population from a regression model based on stream size and, 2) whole-lake mark and recapture estimates. In addition, we used a re-sampling procedure to evaluate the effect of trading off sampling effort between the regression and mark-recapture models. Population estimates derived from the regression model ranged from 132,000 to 377,000 while mark-recapture estimates of marked recently metamorphosed juveniles and parasitic sea lampreys ranged from 536,000 to 634,000 and 484,000 to 1,608,000, respectively. The precision of the estimates varied greatly among estimation procedures and years. The integrated estimate of the mark-recapture and spawner regression procedures ranged from 252,000 to 702,000 transformers. The re-sampling procedure indicated that the regression model is more sensitive to reduction in sampling effort than the mark-recapture model. Reliance on either the regression or mark-recapture model alone could produce misleading estimates of abundance of sea lampreys and the effect of the control program on sea lamprey abundance. These analyses indicate that the precision of the lake-wide population estimate can be maximized by re-allocating sampling effort from marking sea lampreys to trapping additional streams.

Young, Robert J.; Jones, Michael L.; Bence, James R.; McDonald, Rodney B.; Mullett, Katherine M.; Bergstedt, Roger A.

2003-01-01

88

The possibility and timing for a sea waterway via the Lake Iznik (Turkey)  

NASA Astrophysics Data System (ADS)

The Sea of Marmara is connected to the Black Sea through the Bosporus strait. The idea of another waterway existed between these seas during the late Quaternary is much of great interest to scientific community. Taking into account the marine microfaunal composition collected from lake surface sediments some researchers claim that there was an alternative waterway connection via the lakes of Iznik and Sapanca, located at the eastward extensions of the Gulf of Gemlik and Izmit Bay, respectively. In addition a Holocene age is suggested for the latest flooding event. On the contrary, other researchers who have questioned the possibility for a waterway connection through these lakes and the lower course of Sakarya River during the Holocene or the late Pleistocene, claim that a marine connection could not be possible for at least the past 500,000 years. On the basis of the global sea-level change and regional tectonic uplift rates, for example, a connection between the Lake Iznik and the Sea of Marmara may not have been possible after 310,000 years BP. Both of the lakes, representing adjacent E-W-oriented narrow depressions, are controlled by the transpressional effects of the northern and central segments of the North Anatolian Fault (NAF) zone since the Late Miocene - Pliocene. On the basis of available seismic reflection data, the deep trough along the southern margin of Lake Iznik has been evolved under the control of a releasing bend system. Similar to the Hersek Pass separating the outer and central sub-basins of the Izmit Bay at present, this system formed the Karsak Pass between the Lake Iznik and the Gulf of Gemlik, and the brackish waters discharged into the Sea of Marmara. At present, the central segment of the NAF cuts this system and extends towards the Gulf of Gemlik, which is separated from the Lake Iznik by the uplifted Karsak sill (+83 m), similar to the pressure ridge on the Hersek Delta. Therefore the main trough of the Lake Iznik existed before the evolution of the NAF, implying that the lake is a superimposed basin. The secondary normal faults observed in the lake and its environs are responsible for the vertical tectonic movements. Depending on these regional changes and those occurred in the east of the Lake Iznik, e.g. a transpressional interruption at Pamukova, the water discharge ceased at the end of middle Pleistocene, even more precise reconstruction of the sea flooding history of the region need other supportive data. The distribution of some dominant benthic foraminifers across the biogeographic barriers can be explained by adaptation of some marine microfaunal composition to their new home. The transition from normal-marine waterway to a brackish lake fauna must be marked by decreases in species diversity about 310,000 years ago. At present the water quality of the Lake Iznik is changing towards mesotrophic stage from brackish stage. Their biogeographic imprints should be looked for in the composition of the entire assemblage, in general, rather than in the presence or absence of a few dominant species.

Alpar, B.

2012-04-01

89

The lakes and seas of Titan: outstanding questions and future exploration  

NASA Astrophysics Data System (ADS)

More than 400 lakes have been identified near Titan's north pole, with sizes that range from a few km2 to seas in excess of 100,000 km2. The lakes and seas fill through rainfall and/or intersection with the subsurface liquid methane table, and provide the first evidence for an active condensable-liquid cycle on another planetary body. Many aspects of Titan's seas are unknown, including their composition, depth, and shoreline characteristics, but are key to understanding Titan's hydrological cycle. In addition to ethane, methane and nitrogen, Titan's seas will likely contain dissolved amounts of many other compounds. It is possible that further chemistry may take place, yielding prebiotic molecules impossible to form in the gas phase. It has even been suggested that autocatalytic chemical cycles might yield far-from-equilibrium abundance patterns or mimic the functionality of biological systems. The Titan Mare Explorer (TiME) is a Discovery-class mission to a Titan sea that provides in situ measurements to constrain Titan's active methane cycle as well as its intriguing prebiotic organic chemistry. The target for TiME is Ligeia Mare, at 78N, 250W, one of the largest seas identified on Titan. TiME would test the Advanced Stirling Radioisotope Generators (ASRGs), and would pioneer low-cost, outer solar system missions. Science objectives for TiME include measuring the chemistry of the sea to determine their role as a source and sink of methane and its chemical products, determining the depth of the sea to help constrain organic inventory, ascertaining marine processes including the nature of the sea surface and sea circulation, and determining sea surface meteorology. TiME science is fundamental, and will provide the first in situ exploration of an extraterrestrial sea, the first in situ measurements of an active liquid cycle beyond Earth, and aid in understanding the limits of life in our solar system.

Stofan, Ellen R.; Lunine, Jonathan; Lorenz, Ralph

2010-04-01

90

Classifying Sea Lamprey Marks on Great Lakes Lake Trout: Observer Agreement, Evidence on Healing Times between Classes, and Recommendations for Reporting of Marking Statistics  

Microsoft Academic Search

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

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

2003-01-01

91

Great Lakes as a Test Model for Profile Response to Sea Level Changes.  

National Technical Information Service (NTIS)

The average annual water level on Lake Michigan rose 0.8 m between 1967 and 1973 causing adjustments in nearshore processes and topography. Assuming 2 mm/yr as a typical rate for sea level rise, it would take 400 years to observe similar adjustments on an...

E. B. Hands

1984-01-01

92

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

93

Control of the sea lamprey (Petromyzon marinus) in Lake Superior, 1953-70  

USGS Publications Warehouse

Although sea lamprey control and heavy plantings of hatchery-reared stock had restored lake trout abundance to prelamprey levels in many areas by 1970, the trout had not yet become self-sustaining. Additional effort will be required to further reduce the effects of lamprey predation.

Smith, Bernard R.; Tibbles, J. James; Johnson, B. G. H.

1974-01-01

94

Selecting Great Lakes Streams for Lampricide Treatment Based On Larval Sea Lamprey Surveys  

Microsoft Academic Search

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

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

2003-01-01

95

Sea/lake water air conditioning at Naval facilities. Final report, October 1978-December 1979  

SciTech Connect

The sea/lake water air conditioning (AC) work at CEL and related efforts by others are summarized, along with annotated references. Computer models for estimating the capital costs and energy use for sea/lake water air conditioning (AC) systems are introduced, and the output from these models exercised on two Naval facilities are presented. It was found that (1) the computer models produced reasonable estimates of the capital cost and energy use of seawater AC systems; (2) the capital cost and energy use of such systems are sensitive to the pipeline length, which is dependent on the seawater temperature near the seafloor; (3) at a hypothetical typical Naval facility represented by the average of the two trial facilities, seawater AC requires 80% less energy than conventional AC, but the capital cost of seawater AC is 60% greater; and (4) at this typical facility the life cycle cost for seawater AC is 25% less than that of conventional AC. Sea/lake water AC is recommended for consideration as an alternative to conventional AC at Naval facilities that adjoin bodies of water, and it is also recommended that the computer models be used to make estimates of the capital cost and energy use of sea or lake water AC systems.

Ciani, J.B.

1980-05-01

96

Techniques and Methods for Estimating Abundance of Larval and Metamorphosed Sea Lampreys in Great Lakes Tributaries, 1995 to 2001  

Microsoft Academic Search

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

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

2003-01-01

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

Glacial Geology of the Champlain Valley: 1966-1970.  

National Technical Information Service (NTIS)

Detailed study of the distribution of surficial materials in the Champlain Valley, Vermont, established a framework for the glacial history and provided basic information relevant to water supply, waste disposal, and sand and gravel resources. Postglacial...

P. W. Wagner

1971-01-01

100

Big Sagebrush: A Sea Fragmented into Lakes, Ponds, and Puddles.  

National Technical Information Service (NTIS)

Pioneers traveling along the Oregon Trail from western Nebraska, through Wyoming and southern Idaho and into eastern Oregon, referred to their travel as an 800 mile journey through a sea of sagebrush, mainly big sagebrush ( Artemisia tridentata). Today ap...

B. L. Welch

2005-01-01

101

[Variability of myxospores in the myxosporidian genus Henneguya depending on host and geography in the transect "Khubsugul Lake (Mongolia)--Baikal Lake--Laptev Sea (Russia)"].  

PubMed

Analysis of variability and estimation of significance of the differences in morphometric parameters of spores have been carried out for three species of the genus Henneguya (Myxosporidia). Representatives of these species collected both in the same water body (but from different host species) and in geographically distant localities were compared. Thus, we compared samples of Henneguya zschokkei from different host species in Chivyrkui Bay of Baical Lake and in Laptev Sea, and also we compared samples of this species from Baikal Lake with those from Laptev Sea. Materials on Henneguya cerebralis from Baikal Lake were compared with those from Khubsugul Lake; samples of H. cutanea from one host species (Siberian dace) but from water bodies of different type (lake or river) were compared. PMID:21874845

Pronin, N M; Batueva, M D

102

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

103

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

104

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Champlain Valley Interstate Air Quality Control Region. 81.48 Section 81...CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain...

2013-07-01

105

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

Microsoft Academic Search

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

Karen Junge; Jody W. Deming; Hajo Eicken

2004-01-01

106

Variation in larval sea lamprey demographics among Great Lakes tributaries: A mixed-effects model analysis of historical survey data  

Microsoft Academic Search

Understanding variation in fish populations is valuable from both a management and an ecological perspective. Great Lakes sea lampreys are controlled primarily by treating tributaries with lampricides that target the larval stage. Great Lakes streams were divided into four categories based on their regularity of parasitic lamprey production inferred from the historic regularity of chemical treatments. This categorization was intended

Gretchen J. A. Hansen; Michael L. Jones

2009-01-01

107

Isolation of Aeromonas salmonicida from sea lamprey (Petromyzon marinus) with furuncle-like lesions in Lake Ontario.  

PubMed

For the past six decades, parasitic sea lampreys (Petromyzon marinus) have caused devastating losses to salmonid fisheries in the Great Lakes. To reduce the number of sea lampreys, the Great Lakes Fishery Commission began a large-scale program based on trapping male sea lampreys, sterilizing them, and releasing sterile males back into streams to compete with fertile males for spawning females. The transfer of lampreys among lakes can potentially lead to the transfer of various pathogens, and this has raised major concerns regarding the possibility of resident fish populations becoming infected by introduced pathogens. During a health inspection of sea lampreys collected from Lake Ontario, lampreys with obvious furuncle-like lesions (1-2 cm in diameter) were noticed. Most of the furuncles occupied the dorso-lateral musculature, and Aeromonas salmonicida subsp. salmonicida was isolated from the kidneys. This bacterium was cultured from kidneys of 2.5% of the sea lampreys collected from two locations within the Lake Ontario watershed in 2004. The identity of bacterial colonies was presumptively verified with biochemical reactions and confirmed with polymerase chain reaction. This is the first report of A. salmonicida infection in sea lamprey in the Great Lakes basin associated with furunculosis. PMID:17984256

Faisal, M; Eissa, A E; Elsayed, E E

2007-10-01

108

Modelling the recruitment effect in a small marine protected area: the example of saltwater lakes on the Island of Mljet (Adriatic Sea)  

Microsoft Academic Search

This paper analyzes potential recruitment effect of endangered bivalve Pinna nobilis in a small marine protected area-Little Lake (Adriatic Sea). A box model has been applied for the estimation of residence time of the lake, forced by tides only at the open end of the lake system. The residence time of Little Lake was estimated to be 54 days. In

Melita PEHARDA

109

Application of remote sensing techniques to understand the mechanisms behind the Caspian Sea lake-level fluctuations  

NASA Astrophysics Data System (ADS)

The Caspian Sea has exhibited significantly wide range of water-level fluctuations in its history. The primary factor for these oscillations has been overwhelmingly ascribed to climate-induced variations; geologic-related processes have been suggested to be trivial and negligible. This work processed TopexPoseidon data to estimate Lake-level heights for the Caspian Sea from the beginning of 1993 to August 2005. In order to improve the accuracy, the new Gravity Recovery and Climate Experiment orbits data, new Sea State Bias model, and Topex Microwave Radiometer drift correction were applied to the default altimetry data. The Caspian Sea hydrologic budget from 1998 to 2005 was also calculated using remote sensing and ground-based data. The National Center for Environmental Prediction Department of Energy Reanalysis 2 meteorological data provided all the variables necessary for the Penman method to estimate evaporation over the Caspian Sea. The Tropical Rainfall Measuring Mission rainfall data was utilized to estimate precipitation onto the Caspian Sea. This study reveals that lake-level changes from 1998 to 2005 are essentially controlled by meteorological factors based on the fact that a relatively minor difference between the water budget residuals and CSLL changes in the Caspian Sea. Moreover, the trend observed in the Caspian Sea lake level over the last several decades is closely correlated with Lake Van and Lake Urmia. However, the relatively higher dissimilarity present in 2000 and 2001 could imply that the Caspian Sea needs to lose some of its water to attain water balance. The two significant earthquakes with normal fault focal mechanisms and magnitudes of 6.8 and 6.5 Mw could be responsible for the Caspian Sea lake-level decline in 2000 and 2001. The contribution of submarine mud volcano eruptions to increase Caspian Sea lake level is likely to be negligible on the basis of submarine mud volcanic eruptions in 2003. Both the crustal deformation based on the GPS measurements in the Caspian Sea region and the amount of oil and natural gas production offshore the Caspian Sea are not causing considerable changes in the Caspian Sea lake level.

Ozyavas, Aziz

110

Microwave remote sensing of ice in Lake Melville and the Labrador Sea  

Microsoft Academic Search

Results from a joint experiment on microwave remote sensing of ice in the Labrador Sea and Lake Melville during March 1982 are presented. Data from sensors carried on the Canada Centre for Remote Sensing (CCRS) Convair-580, including Ku-band scatterometer and K-band radiometer profiles andX-, C-, andL-band synthetic aperture radar (SAR) imagery, were analyzed in conjunction with aerial photography and surface

SUSAN A. DIGBY-ARGUS; ROBERT K. HAWKINS; KESHAVA P. SINGH

1987-01-01

111

Landslides along the Jordanian Dead Sea coast triggered by the lake level lowering  

Microsoft Academic Search

The level of the Dead Sea lowers 1m\\/year and this rate is in acceleration. The decline is causing one of the major environmental\\u000a disasters of the twenty-first century. The freshwater resources management policy of Israel, Jordan, and Palestine controls\\u000a the phenomenon. Since the 1960s, the level of this terminal lake dropped by 28m and its surface shrunk by one-third. In

D. Closson; N. Abou Karaki; F. Hallot

2010-01-01

112

Strontium isotopic, chemical, and sedimentological evidence for the evolution of Lake Lisan and the Dead Sea  

Microsoft Academic Search

Precise strontium isotope ratios, combined with chemical analyses and sedimentological information, are used to monitor the water sources and the evolution of the Dead Sea and its late Pleistocene precursor, Lake Lisan (70-18 kyr B.P.). The materials analyzed include bulk aragonite, water-leached soluble salts, and residual aragonite and gypsum from the Lisan Formation in the Perazim Valley (near the SW

M. Stein; A. Starinsky; A. Katz; S. L. Goldstein; M. Machlus; A. Schramm

1997-01-01

113

Assessing the Application of SeaWiFS Ocean Color Algorithms to Lake Erie  

NASA Astrophysics Data System (ADS)

The feasibility of monitoring phytoplankton chlorophyll a concentrations in Lake Erie is assessed by applying globally calibrated ocean color algorithms to spatially and temporally collocated measurements of SeaWiFS remote sensing reflectance. Satellite-based chlorophyll a retrievals were compared with fluorescence-based measurements of chlorophyll a from 68 field samples collected across the lake between 1998 and 2002. Twelve ocean color algorithms, one regional algorithm derived for the Baltic Sea's Case 2 inland waters, and a set of regional algorithms developed for the western, central and eastern basins of Lake Erie were considered. While none of the ocean-color algorithms performed adequately, the outlook for the use of regionally calibrated and validated algorithms, with forms similar to the oceanic algorithms, is promising over the central and eastern basins of the lake. The application of several procedures for screening clouds and other atmospheric effects was found to significantly reduce a component of misfit due to unresolved atmospheric contamination in most regions of the lake. Statistical measures of performance for the regional algorithms were particularly good in the eastern basin, while additional improvements might be realized from a better understanding of other color-producing agents (CPAs) in the central basin. In the western basin, other CPAs confound the signal so significantly that different approaches to algorithm development will be needed. In the western basin of the lake, remaining errors due to unresolved atmospheric effects are expected to be small compared with errors remaining due to inadequate separation of chlorophyll a from other CPAs.

Witter, D. L.; Ortiz, J. D.; Palm, S.; Heath, R. T.; Budd, J. W.

2008-12-01

114

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

115

New Approach to Measuring the Frequency of Sea Lamprey Wounds in Fish Stocks in the Great Lakes  

Microsoft Academic Search

I constructed an improved index for measuring the frequency of wounds in prey fish stocks caused by sea lampreys Petromyzon marinus in the Great Lakes. Previous indices did not make use of all of the available data and did not correct for sampling and observational errors. I developed two statistical models and fitted them to sea lamprey wounding data for

Lawrence D. Jacobson

1989-01-01

116

The sources and evolution of sulfur in the hypersaline Lake Lisan (paleo-Dead Sea)  

NASA Astrophysics Data System (ADS)

?34S values in gypsum are used to evaluate the fate of sulfur in the hypersaline Lake Lisan, the late Pleistocene precursor of the Dead Sea (70 14 ka BP), and applied as a paleo-limnological tracer. The Ca-chloride Lake Lisan evolved through meromictic periods characterized by precipitation of authigenic aragonite and holomictic episodes characterized by enhanced gypsum precipitation. The lake deposited two major gypsum units: the Lower Gypsum unit (deposited at 56 ka) showing ?34S values of 18 20, and the Upper Gypsum unit (deposited at 17 ka) displaying significantly higher ?34S values of 26 28. Laminated and disseminated gypsum, residing within the aragonite, exhibit ?34S values in the range of - 26 to 1. The isotopic composition of the gypsum was dictated by freshwater sulfate input that replenished the upper layer of the lake (the mixolimnion), bacterial sulfate reduction (BSR) that occurred under the anoxic conditions of the lower brine (the monimolimnion), and mixing between these two layers. During meromictic periods, the sulfate reservoir in the lower brine was replenished by precipitation of gypsum from the upper layer, and its subsequent dissolution due to sulfate deficiency induced by BSR activity. This process describes a sulfur pump mechanism and its effect on ?34S in the water can be modeled by a modified Rayleigh distillation equation. Steady state ?34S values (40) were reached in the lower brine after long meromictic periods. Following overturn episodes, induced by diminishing freshwater input and lake level decline, large quantities of ?34S enriched gypsum precipitated. The negative ?34S values in laminated and disseminated gypsum provide evidence for BSR activity in the lower brine that removed isotopically depleted sulfides from the water column, causing significant isotopic enrichment of remaining sulfate. Following the lake desiccation, the sediments were exposed and the latter sulfides oxidized and re-crystallized as gypsum.

Torfstein, Adi; Gavrieli, Ittai; Stein, Mordechai

2005-07-01

117

Strontium isotopic, chemical, and sedimentological evidence for the evolution of Lake Lisan and the Dead Sea  

NASA Astrophysics Data System (ADS)

Precise strontium isotope ratios, combined with chemical analyses and sedimentological information, are used to monitor the water sources and the evolution of the Dead Sea and its late Pleistocene precursor, Lake Lisan (70-18 kyr B.P.). The materials analyzed include bulk aragonite, water-leached soluble salts, and residual aragonite and gypsum from the Lisan Formation in the Perazim Valley (near the SW shore of the Dead Sea). The residual aragonite and the associated soluble salts display systematic fluctuations in 17Sr/86Sr ratios between 0.70803 and 0.70806 and from 0.70805 to 0.70807, respectively. In individual soluble salt-residual aragonite pairs, the soluble salt displays a higher 87Sr/86Sr ratio. Gypsum samples yield 17Sr/86Sr ratios similar to the soluble salts from adjacent layers in the section. This shows that, in individual samples, the source of Sr in aragonite was distinct from that in soluble salts and the gypsum. The sterility of the Lisan sediments, their strictly nonbioturbated fine lamination, and their high content of chloride salts indicate that Lake Lisan was a saline, or even hypersaline water body. In the absence of alternative sources of HCO 3- and S0 42- the abundance of primary aragonite and gypsum in the Lisan column reflects an import of very large volumes of freshwater into the otherwise saline lake, resulting in a density stratification of this water body. The history of the upper water layer and that of the lower brine is reflected in the chemical and strontium isotope composition of the aragonite and in that of the associated soluble salts and in the gypsum samples, respectively. Whereas the bicarbonate and much of the Ca 2+ required for aragonite crystallization were supplied by the freshwater, the complementary Ca 2+ (and Sr 2+) were added by the lower brine. The upper water layer of Lake Lisan acted as a SO 42- capacitor during the lake's rise periods. It was removed therefrom, as prominent gypsum beds, upon climatic-induced (drier period) mixing or even complete overturn of the lake. The evolution of Lake Lisan took place between two distinct modes. The first was characterized by an extensive supply of freshwater and resulted in a rise of the lake's level, a (density) layered structure, and precipitation of aragonite. The second mode was marked by a diminishing freshwater input, resulting in mixing or complete overturn of its water, and precipitation of gypsum. These two modes reflect the climatic evolution of the region in the late Pleistocene which fluctuated between drier and wetter periods. The transition to the Holocene is accompanied by the dry up of Lake Lisan and its contraction to the present Dead Sea.

Stein, M.; Starinsky, A.; Katz, A.; Goldstein, S. L.; Machlus, M.; Schramm, A.

1997-09-01

118

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

Federal Register 2010, 2011, 2012, 2013

...system was modified by adding electric bridge opening motors to swing the draw open...in the event of a power outage, local bridge operation controls installed at the tenders building on the bridge to be used to locally operate the...

2013-03-06

119

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

120

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

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

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

123

U-series and oxygen isotope chronology of the mid-Pleistocene Lake Amora (Dead Sea basin)  

Microsoft Academic Search

This study establishes for the first time the chronology and limnological history of Lake Amora (Dead Sea basin, Israel), whose deposits (the Amora Formation) comprise one of the longest exposed lacustrine records of the Pleistocene time. The Amora Formation consists of sequences of laminated primary aragonite and silty-detritus, Ca-sulfate minerals, halite and clastic units. This sedimentary sequence was uplifted and

Adi Torfstein; Alexandra Haase-Schramm; Nicolas Waldmann; Yehoshua Kolodny; Mordechai Stein

2009-01-01

124

Development and Evaluation of a New Predictive Model for Metamorphosis of Great Lakes Larval Sea Lamprey ( Petromyzon marinus) Populations  

Microsoft Academic Search

Accurate forecasts of the number of larval sea lamprey (Petromyzon marinus) within a stream that will enter into metamorphosis are critical to currently used methods for allocating lampricide treatments among streams in the Great Lakes basin. To improve our ability to predict metamorphosis we used a mark-recapture technique, involving the marking of individual larval lamprey with sequentially coded wire tags,

Andrew J. Treble; Michael L. Jones; Todd B. Steeves

2008-01-01

125

A field test verifies that pheromones can be useful for sea lamprey ( Petromyzon marinus ) control in the Great Lakes  

Microsoft Academic Search

Pheromone-baited traps have proven highly effective for managing insect pests by selectively removing re- productively active adults prior to mating. Here, we report a field test of two pheromones produced by the sea lamprey, Petromyzon marinus, which may be useful for controlling pest populations in the Laurentian Great Lakes. In the Trout River, Michigan, we demonstrated that (i) 90% of

C. Michael Wagner; Michael L. Jones; Michael B. Twohey; Peter W. Sorensen

2006-01-01

126

Prehistoric dietary adaptations among hunter-fisher-gatherers from the Little Sea of Lake Baikal, Siberia, Russian Federation  

Microsoft Academic Search

Dietary adaptations of prehistoric hunter-gatherers from Neolithic and Early Bronze Age cemeteries in the Little Sea region of Cis-Baikal (the region to the west and north of Lake Baikal) are explored using stable isotopes of carbon and nitrogen. Stable isotope data, including stable carbon isotopes from bone carbonate, are presented for 22 individuals from the site of Kurma XI, dated

M. Anne Katzenberg; Hugh G. McKenzie; Robert J. Losey; Olga I. Goriunova; Andrzej Weber

127

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

128

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

2008-08-29

129

Application of Geophysical Methods and Numerical Models to Quantify Solute Transport Into a Fresh-Water Lake: Sea of Galilee, Israel  

NASA Astrophysics Data System (ADS)

The Sea of Galilee is the lowest freshwater lake on Earth, covering a pull-apart basin along the Dead Sea transform. Saline groundwater emerges through onshore and offshore springs and through flux from the lake's sediments. In this study, we combined geophysics, geology and numerical models to quantify groundwater and chloride discharge rates into the Sea of Galilee. The results have practical implications for management of the lake and the surrounding aquifers. Multi-channel seismic reflection data define two distinct zones beneath the lake: a deep graben (aquitard) that underlies most of the lake, and shallow pre-rift units (aquifers) underlying the northwestern faulted part of the lake. Applying the novel surface marine modification of the TDEM (Time Domain Electromagnetic) method, the spatial distribution of brines in the sediments below the lake was delineated. Resistivities of 1.0 and 0.5 ohm-m were detected at depths of about 10 m below the lake bottom in most of the lake area, equivalent to approximately 11,000 and 22,000 mgCl/l, respectively. Relatively fresh groundwater was detected beneath most of the shoreline. It is hypothesized that the brine was leached from the sediments beneath the lake's margins due to forceful topography-driven flow systems, but still is trapped beneath the central part of the lake. The detection of shallow brine in the lake's sediment has lead us to propose that in the late Pleistocene, during a short high-stand phase of former Lake Lisan, its saline water percolated into the subsurface. Since its recession and the instantaneous formation of the freshwater lake, the Sea of Galilee, the previously intruded brine has been flushed backwards towards the lake. Numerical simulations of fluid flow and of solute and heat transport show that a high-stand period of approximately 1,000 years in Lake Lisan was sufficient for saline water to percolate deep into the subsurface. Results of 1-D advective-dispersive chloride transport numerical simulations that take into account sedimentation and compaction at the lake bottom were compared with measured chloride concentration profiles in sediment cores. The calculated results validate the hypothesis that Lake Lisan solutes are currently discharged into the Sea of Galilee, and indicate that upward water velocity in the sediment ranges between 9 and 22 mm/year, implying that the total solute discharge into the lake induced by compaction is less than 5% of the total discharge.

Hurwitz, S.; Gvirtzman, H.

2002-12-01

130

Discussion: a critique of Possible waterways between the Marmara Sea and the Black Sea in the late Quaternary: evidence from ostracod and foraminifer assemblages in lakes ?znik and Sapanca, Turkey, Geo-Marine Letters, 2011  

NASA Astrophysics Data System (ADS)

The identification of past connection routes between the Black Sea and the Sea of Marmara, other than the traditional one through to the Bosphorus Strait, would be of considerable interest to the international scientific community. Nazik et al. (Geo-Mar Lett 31:75-86 (2011) doi:10.1007/s00367-010-0216-9) suggest the possibility of two alternative waterway connections via lakes Sapanca and ?znik. Their Black Sea to Sea of Marmara multi-connection hypothesis, which is based on undated marine fossils collected in both lakes from surficial grab samples, conflicts with many earlier studies. In this contribution, the hypothesis and the underlying data are discussed in the light of previous tectonic, sedimentological and limnological findings showing that it is impossible to have had marine connections through lakes Sapanca and ?znik during the last 11.5 ka. Global sea-level trends and tectonic uplift rates would accommodate a connection between the Sea of Marmara and Lake ?znik in the middle Pleistocene. Uplift rates for the northern block of the North Anatolian Fault, when compared with the global sea-level curve, clearly indicate that there cannot have been a connection through the ?zmit Gulf-Lake Sapanca-Sakarya Valley for at least the past 500 ka. Moreover, borehole sediments along the western shores of Lake Sapanca, which reach down to the bedrock, do not contain any marine fossils.

Yalt?rak, Cenk; lgen, Umut B.; Zabc?, Cengiz; Franz, Sven Oliver; n, Sena Aker; Sak?n, Mehmet; a?atay, M. Nam?k; Alpar, Bedri; ztrk, Kurultay; Tuno?lu, Cemal; nl, Selma

2012-06-01

131

Chemical tracing of salinity sources in Lake Kinneret (Sea of Galilee), Israel  

Microsoft Academic Search

Lake Kinneret is a freshwater lake in northern Israel that receives a major part of its salt input from unmonitored springs that discharge through the lake's bottom. We attempt to characterize the nature of these springs by estimating their chemical composition. While the springs around Lake Kinneret are subject to wide spatial and temporal variations in their ionic concentrations, specific

Yehoshua Kolodny; Amitai Katz; Abraham Starinsky; Tamar Moise; Ehud Simon

1999-01-01

132

Low-head Sea Lamprey Barrier Effects on Stream Habitat and Fish Communities in the Great Lakes Basin  

Microsoft Academic Search

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

Hope R. Dodd; Daniel B. Hayes; Jeffery R. Baylis; Leon M. Carl; Jon D. Goldstein; Robert L. McLaughlin; David L. G. Noakes; Louise M. Porto; Michael L. Jones

2003-01-01

133

Remote sensing algorithms for lakes Vattern and Vanern, Sweden, based on the SeaWiFS and MERIS bands  

NASA Astrophysics Data System (ADS)

Through a combination of modeling and field work, we have investigated the possibilities of developing algorithms for the SeaWiFS and MERIS sensors which estimate the concentrations of chlorophyl a and phaeophytin a, dissolved yellow substances, and suspended particulate inorganic material in the upper water layer of Lakes Vaettern, and Vaenern the two largest lakes in Sweden. These concentrations are linked to the absorption and backscattering coefficients through a series of empirical relationships and ultimately radiance reflectance is estimated as a function of the ratio of backscattering to absorption. Model parameterization, i.e. the development of the empirical relationships linking the optically active substances to the inherent optical properties is based on both in situ measurements, and laboratory analyses specific to each lake. The frequency distributions of the optically active concentrations in each lake were estimated form long term monitoring data collected by the Swedish Environmental Protection Agency. Simulations which randomly varied the optically active substances based on their frequency distributions were used to generate synthetic data sets which could be used to examine possible remote sensing algorithms. The results of our modeling, suggest that both SeaWiFS and MERIS can provide useful estimates of yellow substances and SPIM in these two lakes. Accurate estimates of chlorophyll depend on measurements of radiance reflectance in the 660nm-680nm chlorophyll absorption band, in order to minimize interference from yellow substance absorption. As a result only the MERIS band 9: band 7 ratio was able to provide useful estimates of chlorophyll concentrations, and the accuracy of these estimates was influenced by variations in yellow substance absorption and variations in the shape of yellow substance absorption spectra measured in each lake.

Pierson, Donald C.; Stroembeck, Niklas

2000-12-01

134

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

135

Greigite detected as dominating remanence carrier in Late Pleistocene sediments, Lisan formation, from Lake Kinneret (Sea of Galilee), Israel  

NASA Astrophysics Data System (ADS)

A rock magnetic investigation of three sedimentary cores of Lisan formation of late Pleistocene age from Lake Kinneret (Sea of Galilee) northern Israel demonstrates that the magnetization of these sediments is controlled by various degrees of a secondary chemical remanent magnetization (CRM) carried by greigite (Fe3S4). This CRM is superimposed on a primary detrital remanent magnetization (DRM) that resides in Ti-magnetite. This finding is independently confirmed by X-ray diffraction (XRD) measurements performed on magnetic extracts of the sediments. The domain state of the greigite is largely single domain behaviour (SD), thus dominating the magnetization. Therefore, the magnetic record retrieve from of these sediments is not reflecting geomagnetic variations but rather chemical rock magnetic properties, resulting from diagenetic processes. The results of our study suggest that paleomagnetic record of greigite bearing sediments should be interpreted with caution because of the following reasons: 1. Geomagnetic secular variations can be biased, due to large coercivity overlap between magnetite and greigite. 2. Alternating field (AF) demagnetization can produce erroneous directions due to vector distortion by acquisition of a gyro-remnant magnetization (GRM). 3. Estimation of relative paleointensity can be hampered by large-scale variations in natural remnant magnetization (NRM) intensity, caused by the acquisition of a secondary CRM of unknown age and unknown extent superimposed on the DRM. The precipitation of greigite requires reducing conditions at the sediment-water interface and/or interstitial water, associated with the presence of sulphur and iron oxides. Reducing conditions are typical of stratified lakes and other stratified water bodies, such as the Dead Sea, paleo-Lake Lisan, temporarily the Eastern Mediterranean Sea, the Caspian Sea, the Black Sea and many other marine basins. According to our findings, paleomagnetic records from such environments carried dominantly by greigite therefore should be treated with care.

Ron, H.; Nowaczyk, N. R.; Frank, U.; Schwab, M. J.; Naumann, R.; Striewski, B.; Agnon, A.

2007-07-01

136

Climate-induced variations in lake levels: A mechanism for short-term sea level change during non-glacial times  

SciTech Connect

Variations in insolation due to periodic orbital parameters can cause climatic changes and associated variations in the intensity of monsoonal circulation. This can lead to significant variations in the levels of internally draining lakes on timescales of 10,000 to 100,000 years in regions affected by the monsoon (20,000 years for orbital precession). These variations may be responsible for small scale (few meters) eustatic sea level changes in an ice-free Earth, and may contribute to sea level changes in the presence of ice as well. The authors have estimated the volume of empty present lake basins in the regions of Asia and North Africa influenced by the monsoon. The surface water volume alone of these basins is equivalent to a two meter difference in sea level, but is considerably augmented by groundwater associated with an increase in lake level. The lake variation mechanism for sea level change has its basis in the Quaternary record of climate change and associated explanatory models. However, the argument also applies to earlier, non-glacial periods of geologic time. Clear evidence for the presence of ice in the Triassic is lacking. However, there is evidence for short-term periodic fluctuations of lake levels as well as sea level during that time. These sea level changes, as well as those in the Devonian, Jurassic, and Cretaceous, may be driven by periodic fluctuation in lacustrine and groundwater storage resulting from orbitally forced changes in monsoon intensity, even in the absence of significant glacial ice.

Jacobs, D. (American Museum of Natural History, N.Y. (United States)); Sahagian, D. (Ohio State Univ., Columbus, OH (United States). Dept of Geological Sciences)

1992-01-01

137

Massive infestation by Amyloodinium ocellatum (Dinoflagellida) of fish in a highly saline lake, Salton Sea, California, USA.  

PubMed

Persistent fish infestation by the parasitic dinoflagellate Amyloodinium ocellatum was found at a highly saline lake, Salton Sea, California, USA. The seasonal dynamics of the infestation of young tilapia was traced in 1997-1998. First appearing in May, it became maximal in June-August, decreased in October and was not detectable in November. Outbreak of the infestation and subsequent mortality of young fish was registered at the Sea at a water temperature and salinity of 40 degrees C and 46 ppt, respectively. Some aspects of the ultrastructure of parasitic trophonts of A. ocellatum and their location on the fish from different size groups are considered. The interactions of parasitological and environmental factors and their combined effect upon fish from the Salton Sea are discussed. PMID:11407406

Kuperman, B I; Matey, V E

1999-12-22

138

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.  

Code of Federal Regulations, 2012 CFR

...The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the territorial...outermost boundaries of the area so delimited): In the State of Vermont: Addison County, Chittenden County, Franklin County,...

2012-07-01

139

Development of the Champlain primary care cardiovascular disease prevention and management guideline  

PubMed Central

Abstract Problem addressed A well documented gap remains between evidence and practice for clinical practice guidelines in cardiovascular disease (CVD) care. Objective of program As part of the Champlain CVD Prevention Strategy, practitioners in the Champlain District of Ontario launched a large quality-improvement initiative that focused on increasing the uptake in primary care practice settings of clinical guidelines for heart disease, stroke, diabetes, and CVD risk factors. Program description The Champlain Primary Care CVD Prevention and Management Guideline is a desktop resource for primary care clinicians working in the Champlain District. The guideline was developed by more than 45 local experts to summarize the latest evidence-based strategies for CVD prevention and management, as well as to increase awareness of local community-based programs and services. Conclusion Evidence suggests that tailored strategies are important when implementing specific practice guidelines. This article describes the process of creating an integrated clinical guideline for improvement in the delivery of cardiovascular care.

Montoya, Lorraine; Liddy, Clare; Hogg, William; Papadakis, Sophia; Dojeiji, Laurie; Russell, Grant; Akbari, Ayub; Pipe, Andrew; Higginson, Lyall

2011-01-01

140

U-series and oxygen isotope chronology of the mid-Pleistocene Lake Amora (Dead Sea basin)  

NASA Astrophysics Data System (ADS)

This study establishes for the first time the chronology and limnological history of Lake Amora (Dead Sea basin, Israel), whose deposits (the Amora Formation) comprise one of the longest exposed lacustrine records of the Pleistocene time. The Amora Formation consists of sequences of laminated primary aragonite and silty-detritus, Ca-sulfate minerals, halite and clastic units. This sedimentary sequence was uplifted and tilted by the rising Sedom salt diapir, exposing 320 m of sediments on the eastern flanks of Mt. Sedom (the Arubotaim Cave (AC) section). The chronology of the AC section is based on U-disequilibrium dating ( 230Th- 234U and 234U- 238U ages) combined with floating ?18O stratigraphy and paleomagnetic constraints. The determination of the 230Th- 234U ages required significant corrections to account for detrital Th and U. These corrections were performed on individual samples and on suites of samples from several stratigraphic horizons. The most reliable corrected ages were used to construct an age-elevation model that was further tuned to the oxygen isotope record of east Mediterranean foraminifers (based on the long-term similarity between the sea and lake oxygen isotope archives). The combined U-series- ?18O age-elevation model indicates that the (exposed) Amora sequence was deposited between 740 and 70 ka, covering seven glacial-interglacial cycles (Marine Isotope Stages (MIS) 18 to 5). Taking the last glacial Lake Lisan and the Holocene Dead Sea lacustrine systems as analogs of the depositional-limnological environment of Lake Amora, the latter oscillated between wet (glacial) and more arid (interglacial) conditions, represented by sequences of primary evaporites (aragonite and gypsum that require enhanced supply of freshwater to the lakes) and clastic sediments, respectively. The lake evolved from a stage of rapid shifts between high and low-stand conditions during 740 to 550 ka to a sabkha-like environment that existed (at the AC site) between 550 and 420 ka. This stage was terminated by a dry spell represented by massive halite deposition at 420 ka (MIS12-11). During MIS10-6 the lake fluctuated between lower and higher stands reaching its highest stand conditions at the late glacial MIS6, after which a significant lake level decline corresponds to the transition to the last interglacial (MIS5) low-stand lake, represented by the uppermost part of the Formation. ?18O values in the primary aragonite range between 6.0 and -1.3 , shifting cyclically between glacial and interglacial intervals. The lowest ?18O values are observed during interglacial stages and may reflect short and intense humid episodes that intermittently interrupted the overall arid conditions. These humid episodes, expressed also by enhanced deposition of travertines and speleothems, seem to characterize the Negev Desert, and in contrast to the overall dominance of the Atlantic-Mediterranean system of rain patterns in the Dead Sea basin, some humid episodes during interglacials may be traced to southern sources.

Torfstein, Adi; Haase-Schramm, Alexandra; Waldmann, Nicolas; Kolodny, Yehoshua; Stein, Mordechai

2009-05-01

141

Effects of sea lamprey (Petromyzon marinus) control in the Great Lakes on aquatic plants, invertebrates and amphibians  

USGS Publications Warehouse

The chemicals 3-trifluoromethyl-4-nitrophenol (TFM) or a combination of TFM and 2a??,5-dichloro-4a??-nitrosalicylanilide (Bayer 73) have been used to control the sea lamprey (Petromyzon marinus) in the Great Lakes for about 20 yr. These chemicals cause some mortalities of Oligochaeta and Hirudinea, immature forms of Ephemeroptera (Hexagenia sp.), and certain Trichoptera, Simuliidae, and Amphibia (Necturus sp.). The combination of TFM and Bayer 73 may affect some Pelecypoda and Gastropoda, but its overall effects on invertebrates are probably less than those of TFM alone. Granular Bayer 73 is likely to induce mortalities among oligochaetes, microcrustaceans, chironomids, and pelecypods. No evidence exists that the lampricides have caused the catastrophic decline or disappearance of any species. The overall impact of chemical control of sea lampreys on aquatic communities has been minor compared with the benefits derived.

Gilderhus, P. A.; Johnson, B. G. H.

1980-01-01

142

Heavy metal-antibiotic resistant bacteria in a lake recreational area  

Microsoft Academic Search

We undertook this study to determine the impact of urbanization on the microbial content of waters of a major recreational area of Lake Champlain. We followed changes in the numbers of total coliforms, fecal coliforms, fecal streptococci, and ascertained resistance of coliforms to heavy metals and antibiotics. We determined the distribution of these bacterial indicators of pollution by examining water

Robert E. Sjogren; Jennifer Port

1981-01-01

143

Reply to Discussion: a critique of Possible waterways between the Marmara Sea and the Black Sea in the late Quaternary: evidence from ostracod and foraminifer assemblages in lakes ?znik and Sapanca, Turkey, Geo-Marine Letters, 2011  

NASA Astrophysics Data System (ADS)

In their discussion of our 2011 paper dealing with possible waterways between the Marmara Sea and the Black Sea in the "late" Quaternary, based on data from ostracod and foraminifer assemblages in lakes ?znik and Sapanca, Turkey, Yalt?rak et al. (Geo-Mar Lett 32:267-274, 2012) essentially reject the idea of any links whatsoever, be they between the Marmara Sea and the lakes ?znik and Sapanca, or further to the Black Sea via the valley of the Sakarya River. The evidence they provide in support of their view, however, is essentially circumstantial, in part conjectural, and also inconclusive considering the findings in favour of linkage between the Marmara Sea and the lakes at the very least, while the proposed connection with the Sakarya River valley remains speculative because of the lack of unambiguous data. On the other hand, Yalt?rak et al. (Geo-Mar Lett 32:267-274, 2012) do raise valid points of concern which deserve careful future investigation, the most important being the possibility of sample contamination from dumped marine sediment used for construction purposes along some parts of the shore of Lake ?znik. We agree that a concerted multidisciplinary effort is required to address the many unresolved issues in connection with the potential waterways proposed by us and others before us.

Nazik, Atike; Meri, Engin; Av?ar, Niyazi

2012-06-01

144

Unveiling microbial life in the new deep-sea hypersaline Lake Thetis. Part II: a metagenomic study.  

PubMed

So far only little is known about the microbial ecology of Mediterranean deep-sea hypersaline anoxic lakes (DHALs). These brine lakes were formed by evaporite dissolution/brine seeps and are important model environments to provide insights into possible metabolisms and distributions of microorganisms on the early Earth. Our study on the Lake Thetis, a new thalassohaline DHAL located South-East of the Medriff Corridor, has revealed microbial communities of contrasting compositions with a high number of novel prokaryotic candidate divisions. The major finding of our present work is co-occurrence of at least three autotrophic carbon dioxide fixation pathways in the brine-seawater interface that are likely fuelled by an active ramified sulphur cycle. Genes for the reductive acetyl-CoA and reductive TCA pathways were also found in the brine suggesting that these pathways are operational even at extremely elevated salinities and that autotrophy is more important in hypersaline environments than previously assumed. Surprisingly, genes coding for RuBisCo were found in the highly reduced brine. Three types of sulphide oxidation pathways were found in the interface. The first involves a multienzyme Sox complex catalysing the complete oxidation of reduced sulphur compounds to sulphate, the second type recruits SQR sulphide:quinone reductase for oxidation of sulphide to elemental sulphur, which, in the presence of sulphide, could further be reduced by polysulphide reductases in the third pathway. The presence of the latter two allows a maximal energy yield from the oxidation of sulphide and at the same time prevents the acidification and the accumulation of S(0) deposits. Amino acid composition analysis of deduced proteins revealed a significant overrepresentation of acidic residues in the brine compared with the interface. This trait is typical for halophilic organisms as an adaptation to the brine's extreme hypersalinity. This work presents the first metagenomic survey of the microbial communities of the recently discovered Lake Thetis whose brine constitutes one of saltiest water bodies ever reported. PMID:22040283

Ferrer, Manuel; Werner, Johannes; Chernikova, Tatyana N; Bargiela, Rafael; Fernndez, Luca; La Cono, Violetta; Waldmann, Jost; Teeling, Hanno; Golyshina, Olga V; Glckner, Frank Oliver; Yakimov, Michail M; Golyshin, Peter N

2011-10-31

145

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

2011-07-13

146

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

Microsoft Academic Search

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

Michael M Hansen; Dylan J Fraser; Thomas D Als; Karen-Lise D Mensberg

2008-01-01

147

Relative Importance of Water Temperature, Water Level, and Lunar Cycle to Migratory Activity in Spawning-Phase Sea Lampreys in Lake Ontario  

Microsoft Academic Search

We analyzed historical trapping records from six Lake Ontario tributaries to (1) compare the relative importance of water temperature, water level, and lunar cycle to migratory activity in upstream-migrating sea lampreys Petromyzon marinus and (2) determine whether the relative importance of these variables differs among streams. We found significant stream-dependent differences in the relative importance of the environmental variables. Water

Thomas R. Binder; Robert L. McLaughlin; D. Gordon McDonald

2010-01-01

148

Factors affecting recruitment dynamics of Great Lakes sea lamprey ( Petromyzon marinus) populations  

Microsoft Academic Search

Knowledge of stockrecruitment dynamics is as important for control of pest species such as the sea lamprey (Petromyzon marinus) as it is for sustainable harvest management of exploited fish species. A better understanding of spatial and temporal variation in recruitment of pest populations may inform managers on where and when to effectively apply different control methods. Sea lamprey stockrecruitment data

Heather A. Dawson; Michael L. Jones

2009-01-01

149

An Assessment of Age Determination Methods for Great Lakes Larval Sea Lampreys  

Microsoft Academic Search

Estimating the age composition and recruitment of populations of invasive sea lampreys Petromyzon marinus necessitates the validation and improvement of age assessment methods that rely on statoliths and length-frequency data. Determining age based on length-frequency distributions is subjective because of heterogeneity in the growth rates of larval sea lampreys (ammocoetes) within and across streams and the resulting overlap in lengths

Heather A. Dawson; Michael L. Jones; Kim T. Scribner; Stacy A. Gilmore

2009-01-01

150

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

151

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

152

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

153

Optimizing Larval Assessment to Support Sea Lamprey Control in the Great Lakes  

Microsoft Academic Search

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

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

2003-01-01

154

Migration history of North Sea houting ( Coregonus oxyrinchus L.) caught in Lake IJsselmeer (The Netherlands) inferred from scale transects of 88 Sr: 44 Ca ratios  

Microsoft Academic Search

.North Sea houting, Coregonus oxyrinchus, became extinct in the River Rhine in the 1940 s and was reintroduced in the 1990 s. To study the migration history of individuals,\\u000a the 88Sr:44Ca ratio of scales of 39 houting (1044 cm TL) caught in Lake IJsselmeer was analysed using laser ablation inductively coupled\\u000a plasma mass spectrometry (LA-ICP-MS). Scales of houting inhabiting freshwater

Jost Borcherding; Carola Pickhardt; Hendrik V. Winter; J. Sabine Becker

2008-01-01

155

Analysis of Lake Baikal's phytoplankton and fluvial input dynamics using SeaWiFS satellite data within the Scope of the Paleoclimate Project CONTINENT  

NASA Astrophysics Data System (ADS)

Multispectral ocean colour satellite data provide a new tool for spatial and temporal limnological data overview. The Ulaan Baatar (Mongolia) HRPT (high resolution picture transmission) station provides the paleoclimate EC-Project CONTINENT "High Resolution CONTINENTal Paleoclimate Record in Lake Baikal (Siberia, Russia)" with daily SeaWiFS data covering the area of south-eastern Siberia. After a SeaWiFS data processing chain with radiometric and atmospheric correction, we use the water leaving reflectances to gain information on phytoplankton and suspended sediment whose dynamics are a response to the present climate forcing. During the CONTINENT Summer cruises in 2001 and 2002, we were able to verify the spectral analysis of SeaWiFS satellite data with a high quality calibration/validation ground truth data set (field spectrometer and fluorometer measurement activities simultaneously to water sampling activities for pigment and suspended matter SPM and DOC analysis and algae counting). The fluviatil input into Lake Baikal is visible in the SeaWiFS data due to its higher loads of suspended matter, further particularly due to the presence of coloured dissolved organic matter (cDOM). These coloured fraction of DOM (mainly humic acids) originate from the bog areas and swampy basins within the Lake Baikal watershed. The so called yellow substances react optically with a strong absorption in the blue spectral bands of SeaWiFS and are therefore ideal tracers for the river input even over long distances from the river inflow. The phytoplankton main pigment chlorophyll-a is made visible by its absorption band in the blue which results in a green reflectance peak. Additional pigment groups (carotinoids, phycobilins) differentiate the spectral shape of the water leaving reflectance depending on the respective main phytoplankton composition. On satellite images obtained in late Summer, we can differentiate between diatom and cyanobacteria-picoplankton dominated surface water areas. This first step of classifying and monitoring the optically visible climate proxies within the lake's surface water layer is followed by semi-analytical bio-optical modelling for quantifying the phytoplankton biomass and the terrigenous input. In summary, the monitoring results from the SeaWiFS time series 2001 to 2003 will then be linked to the mooring data (South Basin and North Basin) and will be incorporated into the CONTINENT water column transfer model for Lake Baikal.

Heim, B.; Oberhaensli, H.; Kaufmann, H.

2003-04-01

156

Socioeconomic Aspects of Lake Trout Rehabilitation in the Great Lakes  

Microsoft Academic Search

During the 1940s and 1950s, the major fisheries for lake trout Salvelinus namaycush in the Great Lakes declined precipitously because of predation by sea lampreys Petromyzon marinus and overfishing. The need to control the sea lamprey and rehabilitate lake trout resulted in the establishment of institutional arrangements among the responsible state, provincial, and federal fishery agencies. The early arrangements were

Randy L. Eshenroder

1987-01-01

157

Multilevel empirical bayes modeling for improved estimation of toxicant formulations to suppress parasitic sea lamprey in the upper great lakes.  

PubMed

Estimation of extreme quantal-response statistics, such as the concentration required to kill 99.9% of test subjects (LC99.9), remains a challenge in the presence of multiple covariates and complex study designs. Accurate and precise estimates of the LC99.9 for mixtures of toxicants are critical to ongoing control of a parasitic invasive species, the sea lamprey, in the Laurentian Great Lakes of North America. The toxicity of those chemicals is affected by local and temporal variations in water chemistry, which must be incorporated into the modeling. We develop multilevel empirical Bayes models for data from multiple laboratory studies. Our approach yields more accurate and precise estimation of the LC99.9 compared to alternative models considered. This study demonstrates that properly incorporating hierarchical structure in laboratory data yields better estimates of LC99.9 stream treatment values that are critical to larvae control in the field. In addition, out-of-sample prediction of the results of in situ tests reveals the presence of a latent seasonal effect not manifest in the laboratory studies, suggesting avenues for future study and illustrating the importance of dual consideration of both experimental and observational data. PMID:21361894

Hatfield, Laura A; Gutreuter, Steve; Boogaard, Michael A; Carlin, Bradley P

2011-03-01

158

Multilevel empirical Bayes modeling for improved estimation of toxicant formulations to suppress parasitic sea lamprey in the upper Great Lakes  

PubMed Central

Summary Estimation of extreme quantal-response statistics, such as the concentration required to kill 99.9% of test subjects (LC99.9), remains a challenge in the presence of multiple covariates and complex study designs. Accurate and precise estimates of the LC99.9 for mixtures of toxicants is critical to ongoing control of a parasitic invasive species, the sea lamprey, in the Laurentian Great Lakes of North America. The toxicity of those chemicals is affected by local and temporal variations in water chemistry, which must be incorporated into the modeling. We develop multilevel empirical Bayes models for data from multiple laboratory studies. Our approach yields more accurate and precise estimation of the LC99.9 compared to alternative models considered. This study demonstrates that properly incorporating hierarchical structure in laboratory data yields better estimates of LC99.9 stream treatment values that are critical to larvae control in the field. In addition, out-of-sample prediction of the results of in situ tests reveals the presence of a latent seasonal effect not manifest in the laboratory studies, suggesting avenues for future study and illustrating the importance of dual consideration of both experimental and observational data.

Hatfield, Laura A.; Gutreuter, Steve; Boogaard, Michael A.; Carlin, Bradley P.

2011-01-01

159

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

2013-07-21

160

Laurentian Great Lakes Basin Climate Change Adaptation.  

National Technical Information Service (NTIS)

The NOAA Great Lakes Regional Collaboration Team, Great Lakes Sea Grant Network, and Old Woman Creek National Estuarine Research Reserve are working with the Great Lakes & Saint Lawrence Cities Initiative to develop specialized training to build the capac...

D. Forsythe D. Nelson H. Elmer R. Held S. Casey

2011-01-01

161

15alpha-hydroxytestosterone induction by GnRH I and GnRH III in Atlantic and Great Lakes sea lamprey (Petromyzon marinus L.).  

PubMed

The sea lamprey (Petromyzon marinus L.) represents one of the two most ancient classes of vertebrates and possesses a functional hypothalamus-pituitary-gonadal axis. However, the presence and functionality of androgens in the sea lamprey remain elusive. Recently, 15alpha-hydroxytestosterone (15alpha-T) has been found in sea lamprey gonads and blood plasma. In this study we examined changes of circulatory concentrations of 15alpha-T in response to gonadotropin releasing hormone (GnRH) treatments. Plasma concentrations of 15alpha-T in sea lamprey increased 2-5 times for all GnRH-injected sea lamprey compared to controls (P < 0.001). However, there were no differences among responses: (1) to the two forms of GnRH (lamprey GnRH I or lamprey GnRH III), (2) to the doses delivered (50, 100, or 200 microg/kg), or (3) between post-injection sample intervals (8 or 24 h). Between lampreys from the Atlantic Ocean and Great Lakes sites, two of seven GnRH form and dosage comparisons showed between-site differences, but were not believed to represent an overall between-site difference. These are the first data to show a response of a C19 steroid to GnRH stimulation in sea lamprey. PMID:15028532

Young, Bradley A; Bryan, Mara B; Sower, Stacia A; Scott, Alexander P; Li, Weiming

2004-04-01

162

Primary producing prokaryotic communities of brine, interface and seawater above the halocline of deep anoxic lake L'Atalante, Eastern Mediterranean Sea.  

PubMed

Meso- and bathypelagic ecosystems represent the most common marine ecological niche on Earth and contain complex communities of microorganisms that are for the most part ecophysiologically poorly characterized. Gradients of physico-chemical factors (for example, depth-related gradients of light, temperature, salinity, nutrients and pressure) constitute major forces shaping ecosystems at activity 'hot spots' on the ocean floor, such as hydrothermal vents, cold seepages and mud volcanoes and hypersaline lakes, though the relationships between community composition, activities and environmental parameters remain largely elusive. We report here results of a detailed study of primary producing microbial communities in the deep Eastern Mediterranean Sea. The brine column of the deep anoxic hypersaline brine lake, L'Atalante, the overlying water column and the brine-seawater interface, were characterized physico- and geochemically, and microbiologically, in terms of their microbial community compositions, functional gene distributions and [(14)C]bicarbonate assimilation activities. The depth distribution of genes encoding the crenarchaeal ammonia monooxygenase alpha subunit (amoA), and the bacterial ribulose-1,5-biphosphate carboxylase/oxygenase large subunit (RuBisCO), was found to coincide with two different types of chemoautotrophy. Meso- and bathypelagic microbial communities were enriched in ammonia-oxidizing Crenarchaeota, whereas the autotrophic community at the oxic/anoxic interface of L'Atalante lake was dominated by Epsilonproteobacteria and sulfur-oxidizing Gammaproteobacteria. These autotrophic microbes are thus the basis of the food webs populating these deep-sea ecosystems. PMID:18059497

Yakimov, Michail M; La Cono, Violetta; Denaro, Renata; D'Auria, Giuseppe; Decembrini, Franco; Timmis, Kenneth N; Golyshin, Peter N; Giuliano, Laura

2007-10-04

163

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

164

@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.

165

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

Code of Federal Regulations, 2013 CFR

...northeasterly end of Marble Island, and west of a line extending from the northeasterly end of Marble Island to the northeasterly side of Cave Island, and southerly to the point on the lower east side of Mallets Head. (f) St. Albans Bay, Vt. An area...

2013-07-01

166

Survival of Juvenile Lake Trout Stocked in Western Lake Huron during 19741992  

Microsoft Academic Search

The population of lake trout Salvelinus namaycush in the main basin of Lake Huron collapsed in the late 1940s from the combined effects of overfishing and predation by sea lampreys Petromyzon marinus. Stocking juvenile lake trout has been one of the key management strategies in efforts toward lake trout rehabilitation. However, the survival of juvenile stocked lake trout has decreased

Michael J. Wilberg; James R. Bence; James E. Johnson

2002-01-01

167

Recruitment Dynamics of Lake Trout in Western Lake Superior during 19881995  

Microsoft Academic Search

Stocks of lake trout Salvelinus namaycush in Lake Superior are recovering from historical collapse. Stocking, control of sea lampreys Petromyzon marinus, and harvest restrictions have aided lake trout recovery, but the contribution of stocked lake trout to contemporary recruitment has not been quantified in western Lake Superior. Using variants of the Ricker stockrecruit model, we evaluated the production of age-7

Lisa M. Corradin; Michael J. Hansen; Donald R. Schreiner; Michael J. Seider

2008-01-01

168

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

169

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

170

Preferred Temperatures of Juvenile Lake Whitefish  

Microsoft Academic Search

Lake whitefish (Coregonus clupeaformis) supported valuable commercial fisheries in all of the Great Lakes until the 1950s to 1960s when their populations collapsed due to overfishing, pollution, and predation by the exotic sea lamprey (Petromyzon marinus). Reduction of these population stresses has permitted significant recovery of the lake whitefish in the upper three Great Lakes since the 1980s, and limited

Thomas A. Edsall

1999-01-01

171

Phylogenetic status of brown trout Salmo trutta populations in five rivers from the southern Caspian Sea and two inland lake basins, Iran: a morphogenetic approach.  

PubMed

Interrelationships, origin and phylogenetic affinities of brown trout Salmo trutta populations from the southern Caspian Sea basin, Orumieh and Namak Lake basins in Iran were analysed from complete mtDNA control region sequences, 12 microsatellite loci and morphological characters. Among 129 specimens from six populations, seven haplotypes were observed. Based on mtDNA haplotype data, the Orumieh and southern Caspian populations did not differ significantly, but the Namak basin-Karaj population presented a unique haplotype closely related to the haplotypes of the other populations (01% Kimura two-parameter, K2P divergence). All Iranian haplotypes clustered as a distinct group within the Danube phylogenetic grouping, with an average K2P distance of 041% relative to other Danubian haplotypes. The Karaj haplotype in the Namak basin was related to a haplotype (Da26) formerly identified in the Tigris basin in Turkey, to a Salmo trutta oxianus haplotype from the Aral Sea basin, and to haplotype Da1a with two mutational steps, as well as to other Iranian haplotypes with one to two mutational steps, which may indicate a centre of origin in the Caspian basin. In contrast to results of the mtDNA analysis, more pronounced differentiation was observed among the populations studied in the morphological and microsatellite DNA data, except for the two populations from the Orumieh basin, which were similar, possibly due to anthropogenic causes. PMID:23020557

Hashemzadeh Segherloo, I; Farahmand, H; Abdoli, A; Bernatchez, L; Primmer, C R; Swatdipong, A; Karami, M; Khalili, B

2012-10-01

172

Lake trout rehabilitation in Lake Huron  

USGS Publications Warehouse

Efforts to restore lake trout (Salvelinus namaycush) in Lake Huron after their collapse in the 1940s were underway in the early 1970s with completion of the first round of lampricide applications in tributary streams and the stocking of several genotypes. We assess results of rehabilitation and establish a historical basis for comparison by quantifying the catch of spawning lake trout from Michigan waters in 1929-1932. Sixty-eight percent of this catch occurred in northern waters (MH-1) and most of the rest (15%) was from remote reefs in the middle of the main basin. Sea lampreys (Petromyzon marinus) increased in the early 1980s in the main basin and depressed spawning populations of lake trout. This increase was especially severe in northern waters and appeared to be associated with untreated populations in the St. Marys River. Excessive commercial fishing stemming from unresolved treaty rights also contributed to loss of spawning fish in northern Michigan waters. Seneca-strain lake trout did not appear to be attacked by sea lampreys until they reached a size > 532 mm. At sizes > 632 mm, Seneca trout were 40-fold more abundant than the Marquette strain in matched-planting experiments. Natural reproduction past the fry stage has occurred in Thunder Bay and South Bay, but prospects for self-sustaining populations of lake trout in the main basin are poor because sea lampreys are too abundant, only one side of the basin is stocked, and stocking is deferred to allow commercial gillnetting in areas where most of the spawning occurred historically. Backcross lake trout, a lake trout x splake (s. Fontinalis x s. Namaycush) hybrid, did not reproduce in Georgian Bay, but this genotype is being replaced with pure-strain lake trout, whose early performance appears promising.

Eshenroder, Randy L.; Payne, N. Robert; Johnson, James E.; Bowen, Charles, II; Ebener, Mark P.

1995-01-01

173

Effectiveness of Using Backpack Electrofishing Gear for Collecting Sea Lamprey ( Petromyzon marinus) Larvae in Great Lakes Tributaries  

Microsoft Academic Search

The effects of water depth, larval density, stream conductance, temperature, lamprey length, and larval escapement were examined to determine the efficiency of sampling sea lamprey (Petromyzon marinus) larvae using direct current (DC) backpack electrofishing gear. A higher proportion of larvae of all sizes were collected per unit sampling effort when sample sites were shallower, contained fewer larvae, or were in

Todd B. Steeves; Jeffrey W. Slade; Michael F. Fodale; Douglas W. Cuddy; Michael L. Jones

2003-01-01

174

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.

2008-01-01

175

Failure of ATP supply to match ATP demand: The mechanism of toxicity of the lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), used to control sea lamprey ( Petromyzon marinus) populations in the Great Lakes  

Microsoft Academic Search

Although the pesticide, 3-trifluoromethyl-4-nitrophenol (TFM), has been extensively used to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes, it is surprising that its mechanism(s) of toxicity is unresolved. A better knowledge of the mode of toxicity of this pesticide is needed for predicting and improving the effectiveness of TFM treatments on lamprey, and for risk assessments regarding

Oana Birceanu; Grant B. McClelland; Yuxiang S. Wang; Michael P. Wilkie

2009-01-01

176

An Objective Method for Forecasting Winds Over Lake Erie and Lake Ontario.  

National Technical Information Service (NTIS)

An objective method for forecasting surface winds over Lake Erie and Lake Ontario is presented. The developmental data consists of 1000-mb geostrophic wind and sea-level pressure forecasts from the Subsynoptic Advection Model for eight United States citie...

C. S. Barrientos

1971-01-01

177

An Objective Method for Forecasting Winds over Lake Erie and Lake Ontario.  

National Technical Information Service (NTIS)

An objective method for forecasting surface winds over Lake Erie and Lake Ontario is presented. The developmental data consisted of 1000-mb geostrophic wind and sea-level pressure forecasts from the Subsynoptic Advection Model for eight United States citi...

C. S. Barrientos

1970-01-01

178

Microbial Community of a Hydrothermal Mud Vent Underneath the Deep-Sea Anoxic Brine Lake Urania (Eastern Mediterranean)  

NASA Astrophysics Data System (ADS)

The composition of a metabolically active prokaryotic community thriving in hydrothermal mud fluids of the deep-sea hypersaline anoxic Western Urania Basin was characterized using rRNA-based phylogenetic analysis of a clone library. The physiologically active prokaryotic assemblage in this extreme environment showed a great genetic diversity. Most members of the microbial community appeared to be affiliated to yet uncultured organisms from similar ecosystems, i.e., deep-sea hypersaline basins and hydrothermal vents. The bacterial clone library was dominated by phylotypes affiliated with the epsilon- Proteobacteria subdivision recognized as an ecologically significant group of bacteria inhabiting deep-sea hydrothermal environments. Almost 18% of all bacterial clones were related to delta- Proteobacteria, suggesting that sulfate reduction is one of the dominant metabolic processes occurring in warm mud fluids. The remaining bacterial phylotypes were related to alpha- and beta- Proteobacteria, Actinobacteria, Bacteroides, Deinococcus-Thermus, KB1 and OP-11 candidate divisions. Moreover, a novel monophyletic clade, deeply branched with unaffiliated 16S rDNA clones was also retrieved from deep-sea sediments and halocline of Urania Basin. Archaeal diversity was much lower and detected phylotypes included organisms affiliated exclusively with the Euryarchaeota. More than 96% of the archaeal clones belonged to the MSBL-1 candidate order recently found in hypersaline anoxic environments, such as endoevaporitic microbial mats, Mediterranean deep-sea mud volcanoes and anoxic basins. Two phylotypes, represented by single clones were related to uncultured groups DHVE-1 and ANME-1. Thus, the hydrothermal mud of hypersaline Urania Basin seems to contain new microbial diversity. The prokaryotic community was significantly different from that occurring in the upper layers of the Urania Basin since 60% of all bacterial and 40% of all archaeal phylotypes were obtained only from mud fluids. The uniqueness of the composition of the active prokaryotic community could be explained by the complex environmental conditions at the site. The interaction of oxygenated warm mud fluids with the cold hypersaline brine of the Urania Basin seems to simultaneously select for various metabolic processes, such as aerobic and anaerobic heterotrophy, sulfide- and methane-dependent chemotrophy along with anaerobic oxidation of methane, sulfate- and metal-reduction.

Yakimov, Michail M.; Giuliano, Laura; Cappello, Simone; Denaro, Renata; Golyshin, Peter N.

2007-04-01

179

Downstream migration of recently transformed sea lampreys before and after treatment of a Lake Michigan tributary with a lampricide  

USGS Publications Warehouse

After the Pere Marquette River was treated with a lampricide in May 1964, the number of recently transformed sea lampreys (Petromyzon marinus) collected in the water-intake structure of a chemical plant near the mouth of the stream dropped 99.5%, from 13,913 (average for 1962-63 and 1963-64) to 76 (average for the next four migration seasons). Average length of the lampreys caught increased markedly after the treatment. In five of the six migration seasons, the catch of downstream migrants was higher in the fall than in the spring.

Hodges, John W.

1972-01-01

180

Multilevel eEmpirical Bayes modeling for improved estimation of toxicant formulations tosuppress parasitic sea lamprey in the Upper Great Lakes  

USGS Publications Warehouse

Estimation of extreme quantal-response statistics, such as the concentration required to kill 99.9% of test subjects (LC99.9), remains a challenge in the presence of multiple covariates and complex study designs. Accurate and precise estimates of the LC99.9 for mixtures of toxicants are critical to ongoing control of a parasitic invasive species, the sea lamprey, in the Laurentian Great Lakes of North America. The toxicity of those chemicals is affected by local and temporal variations in water chemistry, which must be incorporated into the modeling. We develop multilevel empirical Bayes models for data from multiple laboratory studies. Our approach yields more accurate and precise estimation of the LC99.9 compared to alternative models considered. This study demonstrates that properly incorporating hierarchical structure in laboratory data yields better estimates of LC99.9 stream treatment values that are critical to larvae control in the field. In addition, out-of-sample prediction of the results of in situ tests reveals the presence of a latent seasonal effect not manifest in the laboratory studies, suggesting avenues for future study and illustrating the importance of dual consideration of both experimental and observational data.

Hatfield, Laura A.; Gutreuter, Steve; Boogaard, Michael A.; Carlin, Bradley P.

2011-01-01

181

Dead sea asphalts: historical aspects  

Microsoft Academic Search

Asphalts are present in the Dead Sea basin in three forms: (1) huge blocks, up to 100 tons in weight, composed of extremely pure (>99.99%) solid asphalt occasionally found floating on the lake, (2) veins, seepages, and cavity and fissure fillings in Lower Cretaceous to Holocene rocks, and (3) ozocerite veins on the eastern shore of the lake. Dead Sea

Nissenbaum

1978-01-01

182

Holocene lake development of two Dalmatian lagoons (Malo and Veliko Jezero, Isle of Mljet) in respect to changes in Adriatic sea level and climate  

Microsoft Academic Search

Within the Austrian IGBP\\/PAGES project Palaeolimnology of AdriaticAlpine Lakes (PAAL), geochemical and diatom analyses were performed on sediment cores of Malo and Veliko Jezero, two karstic coastal lakes on the island Mljet, Croatia. Combined with diatom calibration, they provide evidence of remarkable environmental changes during the Holocene. The formation of the lakes in the early Holocene was triggered by a

Sybille Wunsam; R. Schmidt; J. Mller

1999-01-01

183

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

184

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

185

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

186

Integrated analysis of magnetic, paleomagnetic and radiometric data in the Lake Kinneret area (northern Israel)  

Microsoft Academic Search

Lake Kinneret (Sea of Galilee) is a main source of fresh water in Israel. The lake is located in the area of complicated tectonic setting at the northern continuation of the Dead Sea Rift. Absence of wells in the lake basin significantly complicates geological-geophysical data analysis. Map of the total magnetic field of the Lake Kinneret area (ship survey) shows

L. Eppelbaum; Z. Ben-Avraham; Y. Katz

2003-01-01

187

Langmuir circulation driving sediment entrainment into newly formed ice: Tank experiment results with application to nature (Lake Hattie, United States; Kara Sea, Siberia)  

NASA Astrophysics Data System (ADS)

Langmuir circulation (Lc) was generated under freezing conditions in saltwater tank experiments through surface wind stress and cross-waves interacting with subsurface return flow. Fine-grained sediments distributed in the tank prior to frazil crystal formation were aligned in parallel streaks in Lc bottom convergence zones. Downwelling at Lc surface convergence zones aligned floating frazil in wind-parallel rows, and individual crystals rotated on helical paths down to the tank bottom and up again to the surface. The crystals interacted with suspended particles in the water column, and with sediment on the tank bottom, preferentially collecting fine-grained particles and enhancing their entrainment into new ice. Evidence includes higher sediment concentrations in ice and ice-interstitial water (ice pore water) as compared to the tank water. Both tank ice and ice interstitial water contain more silt-sized particles than tank water suspension load and tank bottom sediment. Sand is reduced in the ice, and clay is about the same concentration in all samples. This points to preferential entrainment of fine particles in newly formed ice supported by Lc-driven circulation. Comparable results of Lc-supported ice particle entrainment were found in Lake Hattie. Comparison of ice sediment from tank experiments run with Kara Sea material to ice particles from the natural Kara setting showed both types of ice sediment have very similar grain size distributions and mineralogical compositions. Results from experiments and nature help to better understand the potentially Lc-driven entrainment of sediment into ice formed in shallow freezing waters.

Dethleff, Dirk; Kempema, E. W.

2007-02-01

188

Genetic Diversity of Wild and Hatchery Lake Trout Populations: Relevance for Management and Restoration in the Great Lakes  

Microsoft Academic Search

The biological diversity of lake trout Salvelinus namaycush in the upper Great Lakes was historically high, consisting of many recognizable morphological types and discrete spawning populations. During the 1950s and 1960s, lake trout populations were extirpated from much of the Great Lakes primarily as a result of overfishing and predation by the parasitic sea lamprey Petromyzon marinus. Investigations of how

Kevin S. Page; Kim T. Scribner; Mary Burnham-Curtis

2004-01-01

189

The National Sea Grant Program.  

ERIC Educational Resources Information Center

|Described is the National Sea Grant College Program which supports education and training, research, and advisory extension services through the National Office of Sea Grant and the Sea Grant Network of 30 programs in coastal and Great Lake states. Water-related topics include water's relationship to nature, society, and human expression.

Spector, Barbara S.

1980-01-01

190

Lakes, Lagerstaetten, and Evolution  

NASA Astrophysics Data System (ADS)

The diversity of terrestrial systems is estimated to be greater than in the marine realm. However no hard data yet exists to substantiate this claim. Ancient lacustrine deposits may preserve an exceptionally diverse fossil fauna and aid in determining continental faunal diversities. Fossils preserved in lake deposits, especially those with exceptional preservation (i.e. Konservat Lagerstaetten), may represent a dependable method for determining species diversity changes in the terrestrial environment because of their faunal completeness. Important Konservat Lagerstaetten, such as the Green River Formation (US) and Messel (Germany), both Eocene in age, are found in lake sediments and show a remarkable faunal diversity for both vertebrates and invertebrates. To date information from nearly 25 lake lagerstaetten derived from different types of lake basins from the Carboniferous to the Miocene have been collected and described. Carboniferous sites derive from the cyclothems of Midcontinent of the US while many Cenozoic sites have been described from North and South America as well as Europe and Australia. Asian sites contain fossils from the Mesozoic and Cenozoic. With this data, insight into the evolutionary processes associated with lake systems can be examined. Do lakes act as unique evolutionary crucibles in contrast to marine systems? The speciation of cichlid fishes in present-day African lakes appears to be very high and is attributed to the diversity of environments found in large rift lakes. Is this true of all ancient lakes or just large rift lakes? The longevity of a lake system may be an important factor in allowing speciation and evolutionary processes to occur; marine systems are limited only in the existence of environments as controlled by tectonics and sea level changes, on the order of tens of millions of years. Rift lakes are normally the longest lived in the millions of years. Perhaps there are only certain types of lakes in which speciation of nonmarine organisms, and thus the evolution of freshwater organisms, can occur in a short geologic timespan. Because of their unique and varied conditions, the evolution of nonmarine organisms may be linked to lake basin type as well as lake longevity.

Kordesch, E. G.; Park, L. E.

2001-12-01

191

Bacterial Diversity in the Haloalkaline Lake Elmenteita, Kenya  

Microsoft Academic Search

Lake Elmenteita is one of the alkaline saline lakes within the Kenyan Rift valley. The lake is situated on the floor of the\\u000a Kenyan Rift Valley at 1,776m above sea level and has no direct outlet. The microbial diversity of the lake was investigated\\u000a using a culture-independent approach. Five different sampling points were selected randomly within the lake. Wet sediments

R. Mwirichia; S. Cousin; A. W. Muigai; H. I. Boga; E. Stackebrandt

2011-01-01

192

Fish community change in Lake Superior, 19702000  

Microsoft Academic Search

Abstract: Changes,in Lake Superiors 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

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

2003-01-01

193

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

194

15?-Hydroxytestosterone induction by GnRH I and GnRH III in Atlantic and Great Lakes sea lamprey ( Petromyzon marinus L.)  

Microsoft Academic Search

The sea lamprey (Petromyzon marinus L.) represents one of the two most ancient classes of vertebrates and possesses a functional hypothalamuspituitarygonadal axis. However, the presence and functionality of androgens in the sea lamprey remain elusive. Recently, 15?-hydroxytestosterone (15?-T) has been found in sea lamprey gonads and blood plasma. In this study we examined changes of circulatory concentrations of 15?-T in

Bradley A. Young; Mara B. Bryan; Stacia A. Sower; Alexander P. Scott; Weiming Li

2004-01-01

195

Status of lake trout rehabilitation on Six Fathom Bank and Yankee Reef in Lake Huron  

USGS Publications Warehouse

Six Fathom Bank, an offshore reef in the central region of Lake Huron's main basin, was stocked annually with hatchery-reared lake trout Salvelinus namaycush during 1985-1998, and nearby Yankee Reef was stocked with hatchery-reared lake trout in 1992, 1997, and annually during 1999-2001. We conducted gill-net surveys during spring and fall to evaluate performances of each of the various strains of lake trout, as well as the performance of the entire lake trout population (all strains pooled), on these two offshore reefs during 1992-2000. Criteria to evaluate performance included the proportion of 'wild' fish within the population, spawner density, adult survival, growth, maturity, and wounding rate by sea lamprey Petromyzon marinus. Although naturally reproduced age-0 lake trout fry were caught on Six Fathom Bank and Yankee Reef, wild lake trout did not recruit to the adult population to any detectable degree. The density of spawning lake trout on Six Fathom Bank (>100 fish/305 m of gill net) during 1995-1998 appeared to be sufficiently high to initiate a self-sustaining population. However, annual mortality estimates for all lake trout strains pooled from catch curve analyses ranged from 0.48 to 0.62, well exceeding the target level of 0.40 suggested for lake trout rehabilitation. Annual mortality rate for the Seneca Lake strain (0.34) was significantly lower than that for the Superior-Marquette (0.69) and Lewis Lake (0.69) strains. This disparity in survival among strains was probably attributable to the lower sea-lamprey-induced mortality experienced by the Seneca Lake strain. The relatively high mortality experienced by adult lake trout partly contributed to the lack of successful natural recruitment to the adult population on these offshore reefs, but other factors were probably also involved. We recommend that both stocking of the Seneca Lake strain and enhanced efforts to reduce sea lamprey abundance in Lake Huron be continued.

Madenjian, Charles P.; DeSorcie, Timothy J.; McClain, Jerry R.; Woldt, Aaron P.; Holuszko, Jeffrey D.; Bowen, Charles A., II

2004-01-01

196

Marine Incursion: The Freshwater Herring of Lake Tanganyika Are the Product of a Marine Invasion into West Africa  

Microsoft Academic Search

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

Anthony B. Wilson; Guy G. Teugels; Axel Meyer

2008-01-01

197

Failure of ATP supply to match ATP demand: the mechanism of toxicity of the lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), used to control sea lamprey (Petromyzon marinus) populations in the Great Lakes.  

PubMed

Although the pesticide, 3-trifluoromethyl-4-nitrophenol (TFM), has been extensively used to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes, it is surprising that its mechanism(s) of toxicity is unresolved. A better knowledge of the mode of toxicity of this pesticide is needed for predicting and improving the effectiveness of TFM treatments on lamprey, and for risk assessments regarding potential adverse effects on invertebrate and vertebrate non-target organisms. We investigated two hypotheses of TFM toxicity in larval sea lamprey. The first was that TFM interferes with oxidative ATP production by mitochondria, causing rapid depletion of energy stores in vital, metabolically active tissues such as the liver and brain. The second was that TFM toxicity resulted from disruption of gill-ion uptake, adversely affecting ion homeostasis. Exposure of larval sea lamprey to 4.6 m gl(-1) TFM (12-h LC50) caused glycogen concentrations in the brain to decrease by 80% after 12h, suggesting that the animals increased their reliance on glycolysis to generate ATP due to a shortfall in ATP supply. This conclusion was reinforced by a 9-fold increase in brain lactate concentration, a 30% decrease in brain ATP concentration, and an 80% decrease in phosphocreatine (PCr) concentration after 9 and 12h. A more pronounced trend was noted in the liver, where glycogen decreased by 85% and ATP was no longer detected after 9 and 12h. TFM led to marginal changes in whole body Na(+), Cl(-), Ca(2+) and K(+), as well as in plasma Na(+) and Cl(-), which were unlikely to have contributed to toxicity. TFM had no adverse effect on Na(+) uptake rates or gill Na(+)/K(+)-ATPase activity. We conclude that TFM toxicity in the sea lamprey is due to a mismatch between ATP consumption and ATP production rates, leading to a depletion of glycogen in the liver and brain, which ultimately leads to neural arrest and death. PMID:19716611

Birceanu, Oana; McClelland, Grant B; Wang, Yuxiang S; Wilkie, Michael P

2009-07-23

198

Petroleum and chlorinated hydrocarbons in water from Lake Manzala and associated canals  

Microsoft Academic Search

Lake Manzala is located at the north eastern edge of Nile Delta in Egypt. It is separated from the Mediterranean sea by a sandy beach ridge. However, the lake is in connection with the sea through three opening nearby Port Said. The area of the lake is about 769 Km² and relatively shallow with an average depth of 1.3 m.

M. I. Badawy; R. A. Wahaab; H. F. Abou Waly

1995-01-01

199

Great Lakes estuaries  

Microsoft Academic Search

ConclusionsAccording to the geomorphology and physiography classification scheme for estuaries proposed by Pritchard (1967) and presented\\u000a in Kennish (1986), Great Lakes estuaries can be classified as Type A: drowned river valleys or rias. The termination of Wisconsinian\\u000a glaciation, which resulted in a eustatic rise in sea level of somewhat over 100 m and the formation of such Atlantic coast\\u000a estuaries

Charles E. Herdendorf

1990-01-01

200

Toxic chemicals in the Great Lakes  

Microsoft Academic Search

The Sea Grant program at the Univ. of Wisconsin is sponsoring studies of toxic chemicals in the Great Lakes. Since the DDT crisis of the 1960's, numerous chemical contaminants have been discovered in the Great Lakes, including PCB's, dioxins, heavy metals, and petroleum products. PCB research has focused on the movement of PCB's through the food chain, their effects on

1979-01-01

201

The Lake Erie response to the January 26, 1978, cyclone  

Microsoft Academic Search

A descriptive analysis of the response of Lake Erie to the passage of the blizzard cyclone of January 26, 1978, is presented. This intense extratropical cyclone, the worst ever to cross the Ohio Valley and Great Lakes regiion of the United States, set numerous record low sea level pressure readings at nearly every recording station surrounding Lake Erie and subjected

J. Steven Dingman; Keith W. Bedford

1984-01-01

202

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

203

Estimated background concentrations of sulfate in dilute lakes  

Microsoft Academic Search

Lake water sulfate values were examined for two areas in western Norway and the western US presently receiving low levels of sulfate in atmospheric deposition. Data from these areas were used to estimate background concentrations of sulfate in lakes found in areas currently receiving acidic deposition. The two areas contain dilute lakes with concentrations of sea-salt corrected Ca + Mg

David F Brakke; Ame Henriksen; Stephen A. Norton

1989-01-01

204

Rehabilitation of lake trout in the Apostle Islands region of Lake Superior  

USGS Publications Warehouse

Marked success of rehabilitation of lake trout in Lake Superior has been due principally to the control of the sea lamprey and closure of the lake trout fishery in 1962 and large-scale plantings of yearling lake trout in 1959-66. After the sea lamprey became established in the late 1940s, spawning stocks of lake trout began to decrease and were almost nonexistent by 1960-61. After control of the sea lamprey and closure of the commercial fishery for lake trout in 1962, the abundance of spawning stocks began to rise and reached the highest levels on record in 1964-66. Successful spawning in 1964 and 1965 was demonstrated by catches of age-0 lake trout in 1965 and 1966, the first evidence of natural reproduction since 1959. Plantings of hatchery-reared lake trout in Wisconsin waters of Lake Superior began in 1952. The percentage of hatchery-reared fish in catches of juvenile lake trout increased almost steadily from 1953 to 1965 (when nearly all were of hatchery origin). The abundance of juvenile fish increased from 1959 to 1962 and remained nearly constant in 1962-66. The success of lake trout plantings was highest in 1959-61 but generally declined after 1961; the success of the plantings was inversely related to the abundance of older lake trout. Annual increments of growth of hatchery-reared lake trout varied from 1.1 to 5.0 inches after planting. The average lengths of fish of identical age-groups varied according to gear of capture, depth of water, and season. More than 65% of the season's growth of age-III lake trout took place after September. The findings indicate that the present rate of stocking lake trout may be higher than necessary to maintain optimum abundance.

Dryer, William R.; King, George R.

1968-01-01

205

Historic and Modern Abundance of Wild Lean Lake Trout in Michigan Waters of Lake Superior: Implications for Restoration Goals  

Microsoft Academic Search

Populations of lake trout Salvelinus namaycushin Lake Superior collapsed in the late 1950s due to overfishing and predation by sea lampreysPetromyzon marinus. A binational effort to restore the lean morphotype of lake trout began with the stocking of hatchery-reared fish followed by the chemical control of sea lampreys and closure of the commercial fishery. Previous com- parisons of the contemporary

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

2003-01-01

206

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...

207

AN INTRODUCTION TO THE PHYSICS AND CHEMISTRY OF SOME LAKES IN NORTHERN ZULULAND  

Microsoft Academic Search

1. Lakes Sibayi and Nhlange on the coastal plain of northern Zululand are warm shallow lakes which exhibit a complex pattern of stratification during summer. In Lake Sifungwe a permanent halocline was found at 10 metres. The source of this deep salt layer is the sea, to which the lake is connected via the Kosi estuary.2. Dissolved oxygen never reaches

B. R. Allanson; J. D. van Wyk

1969-01-01

208

Lake fisheries need lamprey control and research  

USGS Publications Warehouse

Since 1921, when the first sea lamprey was recorded from Lake Erie, concern about this parasite in the Great Lakes above Niagara Falls, where previously it had never occurred, grew successively. At first, the concern was shared only in scientific circles, but as the parasite continued its persistent and rapid spread throughout the upper Great Lakes this concern was voiced by state conservation departments, the U.S. Fish and Wildlife Service, and interested fishermen. Catches of lake trout especially, and other species secondarily, began to fall below anything representing normal fluctuations in abundance. The fishing industry on Lake Huron and Lake Michigan became extremely concerned due to the fact that income was diminishing greatly. Producers on Lake Superior were fearful that the same decline in production would soon characterize their fishery.

Moffett, James W.

1953-01-01

209

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) 7½ minute topographic quadrangle maps that cover the State of Connecticut, plus other officially named lakes i...

210

Glacioisostasy and Lake-Level Change at Moosehead Lake, Maine  

USGS Publications Warehouse

Reconstructions of glacioisostatic rebound based on relative sea level in Maine and adjacent Canada do not agree well with existing geophysical models. In order to understand these discrepancies better, we investigated the lake-level history of 40-km-long Moosehead Lake in northwestern Maine. Glacioisostasy has affected the level of Moosehead Lake since deglaciation ca. 12,500 14C yr B.P. Lowstand features at the southeastern end and an abandoned outlet at the northwestern end of the lake indicate that the lake basin was tilted down to the northwest, toward the retreating ice sheet, by 0.7 m/km at 10,000 14C yr B.P. Water level then rose rapidly in the southeastern end of the lake, and the northwestern outlet was abandoned, indicating rapid relaxation of landscape tilt. Lowstand features at the northwestern end of the lake suggest that the lake basin was tilted to the southeast at ca. 8750 14C yr B.P., possibly as the result of a migrating isostatic forebulge. After 8000 14C yr B.P., water level at the southeastern end was again below present lake level and rose gradually thereafter. We found no evidence suggesting that postglacial climate change significantly affected lake level. The rebound history inferred from lake-level data is consistent with previous interpretations of nearby relative sealevel data, which indicate a significantly steeper and faster-moving ice-proximal depression and ice-distal forebulge than geophysical models predict. ?? 1998 University of Washington.

Balco, G.; Belknap, D. F.; Kelley, J. T.

1998-01-01

211

Sea Grant: Enhancing K-12 Education.  

ERIC Educational Resources Information Center

|Sea Grant is a major contributor to marine and aquatic education in K-12 classrooms through curriculum development, teacher education, school programs at field sites, and educational research. Describes Sea Grant's efforts in these areas. Specific programs outlined include Operation Pathfinder, Ohio Sea Grant Partnerships for Great Lakes

Fortner, Rosanne W.

1998-01-01

212

Climate-induced variations in lake levels: A mechanism for short-term sea level change during non-glacial times  

Microsoft Academic Search

Variations in insolation due to periodic orbital parameters can cause climatic changes and associated variations in the intensity of monsoonal circulation. This can lead to significant variations in the levels of internally draining lakes on timescales of 10,000 to 100,000 years in regions affected by the monsoon (20,000 years for orbital precession). These variations may be responsible for small scale

D. Jacobs; D. Sahagian

1992-01-01

213

3 CFR - National Policy for the Oceans, Our Coasts, and the Great Lakes  

Code of Federal Regulations, 2010 CFR

...resilient, and sustainable oceans, coasts, and Great Lakes...future generations. Yet, the oceans, coasts, and Great Lakes...Challenges include water pollution and degraded coastal water...disease, rising sea levels, and ocean acidification. Oceans...

2010-01-01

214

Population Dynamics of Lake Ontario Lake Trout during 19852007  

Microsoft Academic Search

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

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

2011-01-01

215

Lake Thompson, Mojave Desert, California: A Desiccating Late Quaternary Lake System.  

National Technical Information Service (NTIS)

In late Pleistocene time, Lake Thompson rose to 710 meters above sea level and covered 950 square kilometers of the western Mojave Desert, California. During the Holocene time, the lake desiccated and is today represented mainly by Rogers, Rosamond, and B...

A. R. Orme R. Yuretich

2004-01-01

216

Lake trout population dynamics in the Northern Refuge of Lake Michigan: implications for future rehabilitation  

USGS Publications Warehouse

The Northern Refuge was established in 1985 as part of the lake trout Salvelinus namaycush rehabilitation effort for Lake Michigan. To evaluate progress toward lake trout rehabilitation in the Northern Refuge, we conducted annual (19912008) gill-net surveys in the fall to assess the adult population and beam trawl surveys in the spring to assess naturally reproduced age-0 lake trout. Our criteria for evaluating progress included the density of wild age-0 fish within the Northern Refuge, the proportion of wild fish within the adult population, density of spawners, adult survival, growth, and wounding rate by sea lampreys Petromyzon marinus. No wild age-0 lake trout were caught in the Northern Refuge during 19912008. Overall, wild lake trout did not recruit to the adult population to any detectable degree. The mean density of spawning lake trout decreased from 45 fish305 m of gill net?1d?1 during 19911999 to only 4 fish305 m?1d?1 during 20002008. Although the sea lamprey wounding rate more than doubled between these two time periods, catch curve analysis revealed that mortality of adult lake trout actually decreased between the two periods. Therefore, the 90% decrease in abundance of spawning lake trout between the two periods could not be attributed to increased sea lamprey predation but instead was probably due in part to the reduced lake trout stocking rate during 19952005. The paucity of natural reproduction in the Northern Refuge during 19912008 most likely resulted from alewife Alosa pseudoharengus interference with lake trout reproduction and from the relatively low lake trout spawner density during 20002008. Our results suggest that the annual stocking rate of lake trout yearlings should be increased to at least 250,000 fish/reef to achieve greater densities of spawners.

Madenjiana, Charles P.; Desorcie, Timothy J.

2010-01-01

217

Salt lake at record levels  

NASA Astrophysics Data System (ADS)

Utah's Great Salt Lake rose 1.6 m between September 1982 and June 1983, the greatest seasonal rise measured in 136 years of record, according to a report published by Ted Arnow, chief of the U.S. Geological Survey (USGS) Water Resources District Office in Salt Lake City. The lake, which continued to rise after Arnow wrote his report, rose 25 cm in December, a record for a 1-month period. On January 1 the lake's height was measured at 1282.03 m above sea level, the highest since 1887.The combined effects of above average rainfall in 1982, above average snowfall in the autumn of 1982 and the spring of 1983, and unseasonably cool weather during the spring of 1983 led to the record rise.

218

Asynchronous ice lobe retreat and glacial Lake Bascom: Deglaciation of the Hoosic and Vermont valleys, southwestern Vermont  

SciTech Connect

Deglaciation of the Hoosic River drainage basin in southwestern Vermont was more complex than previously described. Detailed surficial mapping, stratigraphic relationships, and terrace levels/delta elevations reveal new details in the chronology of glacial Lake Bascom: (1) a pre-Wisconsinan proglacial lake was present in a similar position to Lake Bascom as ice advanced: (2) the northern margin of 275m (900 ft) glacial Lake Bascom extended 10 km up the Vermont Valley; (3) the 215m (705 ft) Bascom level was stable and long lived; (4) intermediate water planes existed between 215m and 190m (625 ft) levels; and (5) a separate ice tongue existed in Shaftsbury Hollow damming a small glacial lake, here named glacial Lake Emmons. This information is used to correlate ice margins to different lake levels. Distance of ice margin retreat during a lake level can be measured. Lake levels are then used as control points on a Lake Bascom relative time line to compare rate of retreat of different ice tongues. Correlation of ice margins to Bascom levels indicates ice retreat was asynchronous between nearby tongues in southwestern Vermont. The Vermont Valley ice tongue retreated between two and four times faster than the Hoosic Valley tongue during the Bascom 275m level. Rate of retreat of the Vermont Valley tongue slowed to one-half of the Hoosic tongue during the 215m--190m lake levels. Factors responsible for varying rates of retreat are subglacial bedrock gradient, proximity to the Hudson-Champlain lobe, and the presence of absence of a calving margins. Asynchronous retreat produced splayed ice margins in southwestern Vermont. Findings from this study do not support the model of parallel, synchronous retreat proposed by many workers for this region.

Small, E.; Desimone, D. (Williams Coll., Williamstown, MA (United States). Dept. of Geology)

1993-03-01

219

Lake trout population dynamics at Drummond Island Refuge in Lake Huron: Implications for future rehabilitation  

USGS Publications Warehouse

The Drummond Island Refuge (DIR) was established in 1985 as part of the rehabilitation effort for lake trout Salvelinus namaycush in Lake Huron. Since then, several strains of hatchery-reared lake trout have been stocked annually at the DIR. An intensive lampricide treatment of the St. Marys River during 1998-2001 was expected to lower the abundance of sea lamprey Petromyzon marinus within the DIR by 2000. We conducted annual gill-net surveys during spring and fall to evaluate the performance of each of the strains of lake trout as well as that of the entire lake trout population (all strains pooled) in the DIR during 1991-2005. The criteria to evaluate performance included the proportion of "wild" fish within the population, spawner density, adult survival, growth, maturity, and wounding rate by sea lampreys. Wild lake trout did not recruit to the adult population to any detectable degree. During 1991-2005, the average density of spawning lake trout appeared to be marginally sufficient to initiate a self-sustaining population. Survival of the Seneca Lake (SEN) strain of lake trout was significantly higher than that of the Superior-Marquette (SUP) strain, in part because of the higher sea-lamprey-induced mortality suffered by the SUP strain. However, other factors were also involved. Apparently SUP fish were more vulnerable to fishing conducted in waters near the refuge boundaries than SEN fish. The St. Marys River treatment appeared to be effective in reducing the sea lamprey wounding rate on SEN fish. We recommend that the stocking of SEN lake trout in the DIR, control of sea lampreys in the St. Marys River, and reduction of commercial fishery effort in waters near the DIR be maintained. ?? Copyright by the American Fisheries Society 2008.

Madenjian, C. P.; Ebener, M. P.; Desorcie, T. J.

2008-01-01

220

Movement and recapture of parasitic-phase sea lampreys (Petromyzon marinus) tagged in the St. Marys River and Lakes Huron and Michigan, 1963-67  

USGS Publications Warehouse

Four sea lampreys 345-445 mm long when tagged in November or early December were recovered in mid-September of the following year, at least 2 months after the end of the normal spawning season. Suggested possible reasons for this unusual occurrence are the extension of the parasitic phase of the life cycle beyond the usual 12 to 20 months, late-season maturation of the gonads, disease, or deleterious effects of the tags.

Moore, Harry H.; Dahl, Frederick H.; Lamsa, Aarne K.

1974-01-01

221

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.

222

The Role of the Great Lakes Fishery Commission in the Solution of Great Lakes Problems  

Microsoft Academic Search

The Great Lakes Fishery Commission was established by treaty between the United States and Canada. Under the terms of the Convention the Commission is charged with the implementation of a program for the control of the sea lamprey and with the coordination of fishery research by various agencies. In-the performance of its duties with respect to sea lamprey the Commission

John L. Farley

1957-01-01

223

Archaea in Yellowstone Lake  

PubMed Central

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, ?6984% of the 454-FLX reads matched archaeal clones representing organisms that are Nitrosopumilus maritimus-like (9697% 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.

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

2011-01-01

224

LAKE FORK  

EPA Science Inventory

The Lake Fork of the Arkansas River Watershed has been adversely affected through mining, water diversion and storage projects, grazing, logging, and other human influences over the past 120 years. It is the goals of the LFWWG to improve the health of Lake fork by addressing th...

225

Mormon Lake.  

National Technical Information Service (NTIS)

It is recommended that Mormon Lake be established as a scenic and recreation natural area. The area has a long history of disturbance and is heavily used by humans at present. The area is dominated by intermittant Mormon Lake itself and typical Transition...

E. L. Smith G. L. Bender

1973-01-01

226

A review of the history of the Baltic Sea, 13.0-8.0 ka BP  

Microsoft Academic Search

The dynamic history of the Baltic Sea during the millennia following the last deglaciation has been one of the main topics for many generations of Quaternary geologists around the Baltic Sea. Based on the present-state-of-knowledge and certain hypotheses, a model for the development during the Baltic Ice Lake, Yoldia Sea, and Ancylus Lake stages are presented. The resund Strait was

Svante Bjrck

1995-01-01

227

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

228

Aromatic hydrocarbon degradation patterns and catechol 2,3-dioxygenase genes in microbial cultures from deep anoxic hypersaline lakes in the eastern Mediterranean sea.  

PubMed

Several mixed cultures able to grow on different aromatic hydrocarbons were obtained from different depths (between 3500 and 3660 m under the sea surface) of water/brine interfaces (1 to 5 m over the estimated brine surface) of three deep hypersaline anoxic basins (Urania, Discovery and Atalante) in the eastern Mediterranean sea. Eight strains which completely removed toluene from the medium in six to 10 days were isolated from one of the mixed cultures obtained from the Urania basin. The strains grew on toluene and yeast extract in the presence of NaCl concentrations of up to 50 and 100 g l(-1), respectively, indicating that they are halotolerant rather than halophilic. Even though DNA fingerprinting methods showed that the strains were strictly related, two groups could be found on the basis of the plasmid profile. Metabolic profiling and partial sequencing (350 bp) of the 16S rDNA showed that the strains were related to Pseudomonas mendocina. A 320 bp fragment of the catechol 2,3-dioxygenase gene from all the strains was aimplified by PCR. The sequence of the fragment showed 100% identity with xylE from pWW53 of Pseudomonas putida MT53 isolated from soil. Southern hybridisation experiments showed that catechol 2,3-dioxygenase is plasmid encoded. PMID:11372653

Brusa, T; Borin, S; Ferrari, F; Sorlini, C; Corselli, C; Daffonchio, D

2001-01-01

229

Lake Pillsbury, Lake County, California.  

National Technical Information Service (NTIS)

Annual total phosphorus and total nitrogen loadings to the lake were estimated and subdivided according to either point or non-point source origion. An assessment of the lake's trophic condition and limiting nutrient is also provided. All data collected b...

1978-01-01

230

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

231

Intermediate results of the radar backscatter study of sea ice in the Beaufort Sea  

Microsoft Academic Search

As a part of the Beaufort Sea segment of the Surveillance Satellite Project (SURSAT), a team of investigators from the University of Kansas conducted experiments to obtain quantitative measurements of radar backscatter from sea ice during the month of March 1979. Thick first-year sea ice, thin first-year sea ice, and an inland fresh water lake were studied using a surface-based

C. V. Delker; R. G. Onstott; R. K. Moore

1980-01-01

232

Cassini Imaging Observations of Titan's High-Latitude Lakes  

NASA Astrophysics Data System (ADS)

ISS observations suggest that Titan's South Pole harbors surface reservoirs of liquid hydrocarbons, as have also been observed at high northern latitudes. The images provide information on the size and spatial distributions of Titan's lakes and seas.

Turtle, E. P.; Perry, J. E.; McEwen, A. S.; West, R. A.; Del Genio, A. D.; Barbara, J.; Dawson, D. D.; Porco, C. C.

2008-03-01

233

Lake Taneycomo  

Microsoft Academic Search

Significant changes in the fishery of 1,730-acre Lake Taneycomo resulted from the construction of Table Rock Dam immediately upstream on White River because water, released through the dam from a relatively low level, is consequently quite cool. Discharge temperatures range from 40 to 60 F, and the cold water influences a large portion of Lake Taneycomo.Netting indicated an excellent population

James P. Fry; Willis D. Hanson

1968-01-01

234

Hydrology, water quality, and nutrient loads to Lake Catherine and Channel Lake, near Antioch, Lake County, Illinois  

USGS Publications Warehouse

From April 21, 1998, through April 30, 1999, the U.S. Geological Survey, in cooperation with the Fox Waterway Agency, conducted an investigation designed to characterize the hydrology, water quality, hydrologic budget, sediment budget, and nutrient budget of Lake Catherine and Channel Lake, Lake County, Illinois. These lakes are the northernmost lakes of the Fox Chain of Lakes. Lake Catherine and Channel Lake are divided into two basins by a submerged ridge but are continuous at the surface. The lakes are marginally to moderately eutrophic. Lake Catherine and Channel Lake have a combined volume of 7,098 acre-feet at a stage of about 736.5 feet above sea level. Lake Catherine and Channel Lake are subject to thermal stratification. Although most of the water in the lakes is well oxidized, nearly anoxic conditions were present at the bottom of Lake Catherine and Channel Lake during part of the summer in 1998. Water enters Lake Catherine and Channel Lake as inflow from surface water in the watershed (61.9 percent), inflow through the State Highway 173 bridge openings (20.7 percent), direct precipitation (8.2 percent), inflow from storm drains (7.2 percent), and inflow of ground water (2.0 percent). Water exits Lake Catherine and Channel Lake as outflow through the State Highway 173 bridge openings (87.8 percent), evaporation (7.2 percent), and as outflow to ground water (5.0 percent). About 5,200 pounds of phosphorus and 107,200 pounds of nitrogen compounds were added to the lakes during the period of investigation. Phosphorus compounds were derived from primarily internal regeneration (40.2 percent), inflow from surface water in the watershed (30.9 percent), inflow from storm drains (12.5 percent), and inflow through the State Highway 173 bridge openings (9.8 percent). Inflowing ground water, waterfowl excrement, precipitation, and atmospheric deposition of particulate matter account for 6.6 percent of the phosphorus load. Nitrogen was derived from inflow of surface water from within the watershed (52.9 percent), internal regeneration (19.5 percent), inflow through the State Highway 173 bridge openings (10.7 percent), precipitation (7 percent), and inflow from storm drains (6.5 percent). Inflowing ground water, waterfowl excrement, and atmospheric deposition of particulate matter account for about 3.4 percent of the nitrogen load. About 2,220 pounds of phosphorus and 52,300 pounds of nitrogen compounds are removed from the lakes, primarily through the openings at State Highway 173. Nitrate, nitrite, ammonia, and dissolved phosphorus are utilized by algae and aquatic macrophytes. Uptake of these nutrients by aquatic macrophytes and algae temporarily removes them from the water column but not from the lake basin. Because the amount of nutrients entering the lake greatly exceeds the amount leaving, the nutrients are concentrated in the sediments at the lake bottom, where the nutrients can be used by the rooted aquatic macrophytes (rooted aquatic plant large enough to be visible to the unaided eye) and released to the water column during reducing conditions. The buildup of nitrogen and phosphorus compounds in the lakes has the potential over time to stimulate algal and plant growth to nuisance levels that have the potential to affect the fishery and detract from the aesthetic quality of these lakes.

Kay, Robert T.; Johnson, Gary P.; Schrader, David L.

2000-01-01

235

Planning for a wider range of water levels along great lakes and ocean coasts  

Microsoft Academic Search

The 1985 and 1986 period of record high water levels on the Great Lakes had some similarities to the situation that may eventually confront the ocean coasts if sea levels rise and global warming occurs. Institutional responses to the Great Lakes situation are described and suggested as a dress rehearsal for future responses to sea level rise.

J. Philip Keillor

1990-01-01

236

Patterns of spread of the zebra mussel (Dreissena polymorphs (Pallas)): the continuing invasion of Belarussian Lakes  

Microsoft Academic Search

The invasion of the freshwaters of Belarus by the zebra mussel, Dreissena polymorpha (Pallas), began at least 200 years ago by the opening of shipping canals linking the Black Sea and Baltic Sea drainage basins. However, zebra mussels have invaded only 93 (16.87o) of 553 studied lakes; at least 20 of these lakes were invaded within in the past 30

Alexander Y. Karatayevr; Lyubov E. Burlakoval; Ladd E. Johnson

2003-01-01

237

Patterns of Spread of the Zebra Mussel ( Dreissena polymorpha (Pallas)): the Continuing Invasion of Belarussian Lakes  

Microsoft Academic Search

The invasion of the freshwaters of Belarus by the zebra mussel, Dreissena polymorpha (Pallas), began at least 200 years ago by the opening of shipping canals linking the Black Sea and Baltic Sea drainage basins. However, zebra mussels have invaded only 93 (16.8%) of 553 studied lakes; at least 20 of these lakes were invaded within in the past 30

Alexander Y. Karatayev; Lyubov E. Burlakova; Dianna K. Padilla; Ladd E. Johnson

2003-01-01

238

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

239

Variation of Great Lakes water levels derived from Geosat altimetry  

Microsoft Academic Search

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

Charles S. Morris; Stephen K. Gill

1994-01-01

240

Variation of Great Lakes water levels derived from Geosat altimetry  

Microsoft Academic Search

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

Charles S. Morris; Stephen K. Gill

1994-01-01

241

Australian salt lakes: their history, chemistry, and biota a review  

Microsoft Academic Search

A vast number of large lakes ( 100 km2) are typically very old features of the Australian landscape; they occupy areas which have changed little tectonically (e.g., they occupy ancient drainage systems in Western Australia or lie in deep depressions such as the Great Artesian Basin: Lake Eyre) and have not been transgressed by the sea since at least the

Patrick De Deckker

1983-01-01

242

Basic limnology of fifty-one lakes in Costa Rica.  

PubMed

We visited 51 lakes in Costa Rica as part of a broad-based survey to document their physical and chemical characteristics and how these relate to the mode of formation and geographical distribution of the lakes. The four oxbow lakes were low in elevation and tended to be turbid, high in conductivity and CO2, but low in dissolved O2; one of these, L. Gandoca, had a hypolimnion essentially composed of sea water. These were similar to the four wetland lakes, but the latter instead had low conductivities and pH, and turbidity was often due to tannins rather than suspended sediments. The thirteen artificial lakes formed a very heterogenous group, whose features varied depending on local factors. The thirteen lakes dammed by landslides, lava flows, or lahars occurred in areas with steep slopes, and were more likely to be stratified than most other types of lakes. The eight lakes that occupy volcanic craters tended to be deep, stratified, clear, and cool; two of these, L. Hule and L. Ro Cuarto, appeared to be oligomictic (tending toward meromictic). The nine glacial lakes, all located above 3440 m elevation near Cerro Chirrip, were clear, cold, dilute, and are probably polymictic. Cluster analysis resulted in three significant groups of lakes. Cluster 1 included four calcium-rich lakes (average 48 mg l-1), Cluster 2 included fourteen lakes with more Si than Ca+2 and higher Cl- than the other clusters, and Cluster 3 included the remaining thirty-three lakes that were generally less concentrated. Each cluster included lakes of various origins located in different geographical regions; these data indicate that, apart from the high-altitude glacial lakes and lakes in the Miravalles area, similarity in lake chemistry is independent of lake distribution. PMID:15162686

Haberyan, Kurt A; Horn, Sally P; Umaa, Gerardo

2003-03-01

243

Restoration and recovery of shallow eutrophic lake ecosystems in The Netherlands: epilogue  

Microsoft Academic Search

During the symposium Restoration and recovery of shallow lake ecosystems in The Netherlands studies on restoration of eutrophic lakes were addressed and discussed. Many Dutch shallow lakes have received high external loadings of phosphorus through supply water that is influenced by the River Rhine and loadings in The Netherlands. Two important Action Plans (the Rhine Action Plan, the North Sea

Louis Van Liere; Ramesh D. Gulati

1992-01-01

244

Groundwater Contribution to Central Asia Lakes Water Supplies and Water Quality  

Microsoft Academic Search

The Central Asia Lakes area (the Aral Sea, the Balkhash Lake, the Issyk-Kul Lake, etc.) is the most convincing example of the development of the desertification process in the arid zone, the specific features of which depend on the current structural dynamic condition of economy, the trend and degree of use of the natural (water) resources. This area is a

E. A. Kontar; A. Yu. Tkachev; D. V. Nikiforov

245

Hydrology of Lake Panasoffkee, Sumter County, Florida  

USGS Publications Warehouse

Lake Panasoffkee, in midwest Sumter County of central Florida, receives water from three creeks and discharges water through Outlet River at an average daily rate of 207 cubic feet per second. The eastern shore of the lake is marsh and wooded swamp with inflow to the lake coming from the northeast and southeast. About 15 percent of the basin contributes surface water to the lake and about 50 percent of the 420-square-mile topographic drainage basin contributes ground water to the lake. The water from the remainder of the basin either evaporates from low areas or directly recharges the Floridan aquifer for discharge outside the basin. The maximum stage on record is 44.28 feet above mean sea level and the minimum stage on record is 37.65 feet above. The lake level is partly affected by the Wysong Dam and has stabilized in recent years at about 40.95 feet above mean sea level. The quality of the water is generally good. The lake supports a favorably balanced fish population even though minor fish kills were reported in 1973 and 1974. These kills were probably the result of algal blooms. (Woodard-USGS)

Taylor, G. F.

1977-01-01

246

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

247

Lake Basin Management Initiative Thematic Paper Conservation and Management Challenges of Saline Lakes: A Review of Five Experience Briefs  

Microsoft Academic Search

Saline lakes occur throughout the world and have significant economic, ecological, biodiversity, and cultural value. In addition to the wide array of human-caused impacts they experience in common with their freshwater counterparts, they are particularly vulnerable to changing hydrologic regimes due to climate change or water diversions. We review experience briefs addressing management issues at five lakes: Aral Sea (Kazakhstan\\/Uzbekistan),

Robert Jellison; Yegor S. Zadereev; Priya Arora DasSarma; John M. Melack; Andrei G. Degermendzhy; Shiladitya DasSarma

248

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.

249

Sea Education Association (SEA)  

NSDL National Science Digital Library

The Sea Education Association (SEA) in Woods Hole, MA provides undergraduates with an opportunity to participate in an academic study-abroad program called the SEA Semester. The program combines intensive research in the areas of oceanography, maritime studies, and nautical science with hands-on experience aboard a traditional sailing ship. Piloting, celestial navigation, and practical seamanship are learned together with oceanographic sampling techniques and marine laboratory procedures. Critical thinking, problem-solving, team-building and leadership skills are emphasized throughout the program. SEA Semester is appropriate for students in marine biology, geology and physical science, environmental studies, American studies, and most other areas within the liberal arts and sciences. Academic credit for SEA Semester is obtained through Boston University.

250

Asian great lakes, especially Lake Biwa  

Microsoft Academic Search

The geological and biological history of Asian great lakes, especially Lake Biwa in Japan, are reviewed. The origins and affiliations of endemic flora and fauna are interpreted in light of current understanding of Lake Biwa. Recent historical changes in the lake, including detrimental impacts on native fauna and water quality are summarized. The social and cultural values associated with Asian

Hiroya Kawanabe

1996-01-01

251

10Be in Lake Lisan sediments A proxy for production or climate?  

Microsoft Academic Search

The geochemical behavior of 10Be in the modern Dead Sea hydrologicallimnological system was studied in order to evaluate the feasibility of using Dead Sea and Lake Lisan (the late Pleistocene precursor of the Dead Sea) sediments as archives of the variations in the 10Be production rate. 10Be concentrations in detrital and aragonite material from Lake Lisan laminated sediments were compared

Reuven Belmaker; Boaz Lazar; Natalya Tepelyakov; Mordechai Stein; Jrg Beer

2008-01-01

252

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

253

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

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

254

Ocean and Great Lakes Awareness Survey.  

ERIC Educational Resources Information Center

|This survey was developed by the Ohio Sea Grant Education Program in 1979. It is been used every four years as a repeated measure of Ohio students' knowledge and attitudes about the oceans and Great Lakes, charting changes in those attributes as means of determining how well Ohio citizens are being prepared for decisionmaking about those bodies

Fortner, Rosanne W.

255

Great lakes: A Look to the Future  

Microsoft Academic Search

Trace toxic contaminants will be the major research focus in the years ahead, since our inland seas appear to be especially sensitive to contaminants. During the 1970s, however, attention centered on pollution from municipal sewage treatment plants. By year 2000 controls are predicted to reduce phosphorus inputs to the Great Lakes from municipal sources by more than half current levels.

W. C. Sonzogni

1982-01-01

256

Diversity of Aphanizomenon flos-aquae (cyanobacterium) populations along a Baltic Sea salinity gradient.  

PubMed

Colony-forming cyanobacteria of the genus Aphanizomenon form massive blooms in the brackish water of the Baltic Sea during the warmest summer months. There have been recent suggestions claiming that the Baltic Sea Aphanizomenon species may be different from Aphanizomenon flos-aquae found in lakes. In this study, we examined variability in the morphology and 16S-23S rRNA internal transcribed spacer (ITS) sequences of A. flos-aquae populations along a salinity gradient from a string of lakes to a fjord-like extension of the Baltic Sea to the open Baltic Sea. Morphological differences among the populations were negligible. We found that the Baltic Sea was dominated (25 out of 27 sequences) by one ITS1-S (shorter band of ITS 1 [ITS1]) genotype, which also was found in the lakes. The lake populations of A. flos-aquae tended to be genetically more diverse than the Baltic Sea populations. Since the lake ITS1-S genotypes of A. flos-aquae are continuously introduced to the Baltic Sea via inflowing waters, it seems that only one ITS1 genotype is able to persist in the Baltic Sea populations. The results suggest that one of the ITS1-S genotypes found in the lakes is better adapted to the conditions of the Baltic Sea and that natural selection removes most of the lake genotypes from the Baltic Sea A. flos-aquae populations. PMID:12406717

Laamanen, Maria J; Forsstrm, Laura; Sivonen, Kaarina

2002-11-01

257

Low frequency response of the lake level on climate effects  

NASA Astrophysics Data System (ADS)

From the historical water level gauge records in Great Lakes, the long periodicity can be found by simply checking the epoch of the lowest water level using100-year records as well as detected in global mean sea level changes. This low frequency could significantly affect the local water supply and ecosystem; however, it can not be recognized in climate and hydrologic models or in situ data. In this study, a novel technique, Ensemble EMD method, is therefore used to analyze the low-frequency spectrum of water gauge data in Great Lakes and Lake Winnipeg. The estimated frequencies in different lakes will be particularly compared and discussed.

Lin, L. C.; Kuo, C. Y.; Shum, C. K.

2009-04-01

258

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

259

Species succession and fishery exploitation in the Great Lakes  

USGS Publications Warehouse

The species composition of fish in the Great Lakes has undergone continual change since the earliest records. Some changes were caused by enrichment of the environment, but others primarily by an intensive and selective fishery for certain species. Major changes related to the fishery were less frequent before the late 1930's than in recent years and involved few species. Lake sturgeon (Acipenser fulvescens) were overexploited knowingly during the late 1800's because they interfered with fishing for preferred species; sturgeon were greatly reduced in all lakes by the early 1900's. Heavy exploitation accompanied sharp declines of lake herring (Leucichthys artedi) in Lake Erie during the 1920's and lake whitefish (Coregonus clupeaformis) in Lake Huron during the 1930's. A rapid succession of fish species in Lakes Huron, Michigan, and Superior that started about 1940 has been caused by selective predation by the sea lamprey (Petromyzon marinus) on native predatory species, and the resultant shifting emphasis of the fishery and species interaction as various species declined. Lake trout (Salvelinus namaycush) and burbot (Lota lota), the deepwater predators, were depleted first; this favored their prey, the chubs (Leucichthys spp.). The seven species of chubs were influenced differently according to differences in size. Fishing emphasis and predation by sea lampreys were selective for the largest species of chubs as lake trout and burbot declined. A single slow-growing chub, the bloater, was favored and increased, but as the large chubs declined the bloater was exploited by a new trawl fishery. The growth rate and size of the bloater increased, making it more vulnerable to conventional gillnet fishery and lamprey predation. This situation in Lakes Michigan and Huron favored the small alewife (Alosa pseudoharengus) which had recently become established in the upper Great Lakes, and the alewife increased rapidly and dominated the fish stocks of the lakes. The successive collapses of various stocks after periods of stable production may give some indication of their sustainable yield. The sea lamprey is being brought under control in Lakes Superior, Michigan, and Huron; lake trout are being established; and chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), kokanee salmon (O. nerka), and the splake, a hybrid of lake trout and brook trout (Salvelinus fontinalis), are being introduced to reestablish a new species balance. Fish stocks are in a state of extreme instability in these lakes. Careful control of stocking programs and fisheries, and coordination of management among the various states of the United States and the province of Canada (Ontario) which manage the fish stocks, will be required to restore and maintain a useful fishery balance.

Smith, Stanford H.

1968-01-01

260

The Lake Erie Response to the January 26, 1978, Cyclone  

NASA Astrophysics Data System (ADS)

A descriptive analysis of the reponse of Lake Erie to the passage of the blizzard cyclone of January 26, 1978, is presented. This intense extratropical cyclone, the worst ever to cross the Ohio Valley and Great Lakes region of the United States, set numerous record low sea level pressure readings at nearly every recording station surrounding Lake Erie and subjected the lake region to sharp temperature drops and high winds. The lake surface was significantly ice covered during the storm event; it remained virtually intact on the entire Western Basin, and partial ice cover breakup occurred over the Central Basin. The investigation of the water level fluctuations induced by the cyclone are based on data acquired from normal meteorological and water level monitoring stations surrounding the lake. The most unusual aspects of the water surface fluctuations include the observance of a pressure suction induced rise in water level in the Western Basin before the storm passed north of the lake; a maximum storm surge setup occurring between Marblehead, Ohio, and Port Colborne, Canada, and not between the ends of the lake; and a separate oscillatory surge occurring at Port Stanley, Canada. The probable causes and reasons for these fluctuations are thoroughly analyzed in the context of existing theories that deal with how a lake surface responds to external atmospheric forcing functions such as wind stress, sea level pressure changes, and resonance. The effect of the ice cover on the water level fluctuations is also presented.

Dingman, J. Steven; Bedford, Keith W.

1984-07-01

261

The Lake Erie response to the January 26, 1978, cyclone  

NASA Astrophysics Data System (ADS)

A descriptive analysis of the response of Lake Erie to the passage of the blizzard cyclone of January 26, 1978, is presented. This intense extratropical cyclone, the worst ever to cross the Ohio Valley and Great Lakes regiion of the United States, set numerous record low sea level pressure readings at nearly every recording station surrounding Lake Erie and subjected the lake region to sharp temperature drops and high winds. The lake surface was significantly ice covered during the storm event; it remained virtually intact on the entire Western Basin, and partial ice cover breakup occurred over the Central Basin. The investigation of the water level fluctuations induced by the cyclone are based on data acquired from normal meterological and water level monitoring stations surrounding the lake. The most unusual aspects of the water surface fluctuations include the observance of a pressure suction induced rise in water level in the Western Basin before the storm passed north of the lake; a maximum storm surge setup occurring between Marblehed, Ohio, and Port Colborne, Canada, and not between the ends of the lake; and a separate oscillatory surge occurring at Port Stanley, Canada. The probable causes and reasons for these fluctuations are thoroughly analyzed in the context of existing theories that deal with how a lake surface responds to external atmospheric forcing functions such as wind stress, sea level pressure changes, and resonance. The effect of the ice cover on the water level fluctuations is also presented.

Dingman, J. Steven; Bedford, Keith W.

262

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

263

Thermal, mixing, and oxygen regimes of the Salton Sea, California, 19971999  

Microsoft Academic Search

The Salton Sea is a shallow (mean depth = 8 m; maximum depth = 15 m), saline (4145 g l-1), intermittently mixing, 57 km long, 980 km2 lake located in the arid southwestern United States. The Sea is a wind driven system, with predominant winds paralleling the long axis of the lake, being strongest in spring and weakest in summer

James M. Watts; Brandon K. Swan; MaryAnn Tiffany; Stuart H. Hurlbert

2001-01-01

264

Historic and modern abundance of wild lean lake trout in Michigan waters of Lake Superior: Implications for restoration goals  

USGS Publications Warehouse

Populations of lake trout Salvelinus namaycush in Lake Superior collapsed in the late 1950s due to overfishing and predation by sea lampreys Petromyzon marinus. A binational effort to restore the lean morphotype of lake trout began with the stocking of hatchery-reared fish followed by the chemical control of sea lampreys and closure of the commercial fishery. Previous comparisons of the contemporary abundance of wild lean lake trout with that from historic commercial fishery statistics indicate that abundance was higher historically. However, this conclusion may be biased because several factors- the inclusion of siscowet (the 'fat' morphotype of lake trout) in the catch statistics, the soak time of nets, seasonal effects on catch per effort, and the confounding effects of effort targeted at lake whitefish Coregonus clupeaformis- were not accounted for. We developed new indices of historic lean lake trout abundance that correct for these biases and compared them with the assessment data from 1984 to 1998 in Michigan waters of Lake Superior. The modern (1984-1998) abundance of wild lean lake trout is at least as high as that during 1929-1943 in six of eight management areas but lower in one area. Measures to promote and protect naturally reproducing populations have been more successful than previously realized.

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

2003-01-01

265

Great Lakes Restoration Crosscut.  

National Technical Information Service (NTIS)

This crosscut budget provides information on Federal funding for Great Lakes restoration work in the following formats: Total Federal funding by agency, which includes national and Great Lakes programs, as well as Great Lakes projects, FYs 2004 enacted-20...

2008-01-01

266

Sea Grant and Invasive Aquatic Plants: A National Outreach Initiative  

Microsoft Academic Search

The National Sea Grant College Program is a NOAA-fund- ed, university-based research and outreach program located in universities in 30 coastal and Great Lake states and Puerto Rico. With a primary mission to \\

HEATHER M. CRAWFORD; DOUGLAS A. JENSEN; BARBARA PEICHEL; PATRICE M. CHARLEBOIS; BARBARA A. DOLL; STRATFORD H. KAY; VICTOR A. RAMEY

267

Associations between water chemistry and fish community composition: a comparison between isolated and connected lakes in northern Sweden  

Microsoft Academic Search

SUMMARY 1. The correlation between water chemistry, physical variables and fish community composition was examined in 40 small (30 ha) coastal lakes in northern Sweden. Twenty of the 40 lakes were isolated from other water bodies and 20 were connected to the Baltic Sea. Lakes were fished in summer, using three different methods. Water chemistry was sampled in late winter

JOHANNA OHMAN; I SHI; GORAN E NGLUND; A NDREAS B LOM; EMMA L INDGREN; H JALMAR L AUDON

268

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

269

Salinity and fish effects on Salton Sea microecosystems: benthos  

Microsoft Academic Search

The Salton Sea, the largest lake in California, has a surface elevation 69 m below sea level which is maintained predominantly\\u000a by the balance of agricultural runoff and evaporation. The lack of outflowing streams is resulting in a gradual buildup of\\u000a salts in the lake, increasing the salinity. A 15 month microcosm experiment was conducted to determine the effects of

E. Paul Simpson; Maria R. Gonzlez; Cheryl M. Hart; Stuart H. Hurlbert

1998-01-01

270

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

271

Boll Weevil Eradication: A Model for Sea Lamprey Control?  

Microsoft Academic Search

Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying

James W. Smith; William D. Swink

2003-01-01

272

TEACH Great Lakes  

NSDL National Science Digital Library

The Education And Curriculum Home site (TEACH) is a new component of the Great Lakes Information Network, with a focus on advancing Great Lakes-related educational materials for the broad audience of educators and students in the Great Lakes region and beyond. TEACH features mini-lessons on Great Lakes topics: environment, history and culture, geography, pollution, careers, and business. Geared for elementary through high school students, the modules are continually expanded and updated and include links to a glossary to help explain scientific terms and acronyms. Also included is a section for questions and answers, and education links. Specific topics within the site include: Great Lakes native flora, water levels on the Great Lakes, native peoples of the Great Lakes region, Great Lakes law and policy, introduction to the Great Lakes, how the lakes were formed, Great Lakes shoreline geology, non-native species, and urban sprawl.

273

Tyee Lake project: Alaska's second lake tap  

Microsoft Academic Search

Environmentally, as well as in terms of pure water energy efficiency, lake taps are an ideal source of power. The basic concept is to tap into the bottom of a high mountain lake to use the high static head of water to spin turns. The Lake Tyee project starts with a tunnel at the lowest possible topographic point and uses

1983-01-01

274

Lake Trout Rehabilitation in Lake Ontario 2005  

Microsoft Academic Search

Abstract Each year we report ,on the ,progress toward rehabilitation of the ,Lake Ontario lake trout population covering the results of stocking, annual assessment surveys, creel surveys, and evidence of natural reproduction observed from all standard surveys performed by USGS and NYSDEC. During 2005, the number of yearling lake trout stocked in May was 45% below the target level of

B. f. Lantry; S. E. Prindle

275

Lake Effects: The Lake Superior Curriculum Guide.  

ERIC Educational Resources Information Center

|This curriculum guide was launched in response to a need for Lake Superior-specific educational materials and contains lessons and activities that can be used to teach about Lake Superior. The lessons in this book are divided into four sections. Each of the first three sections has a background section that provides basic information about Lake

Beery, Tom; And Others

276

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

277

Biogeochemistry of the Salton Sea, California  

NASA Astrophysics Data System (ADS)

The Salton Sea is a saline, closed basin lake 70 meters below MSL in the southern desert of California. It is the largest lake in California with a surface area of 945 km2 and an annual inflow of 1,600 million m3. The Sea is hypereutrophic due to nutrient inputs from farm runoff, and anaerobic conditions in the bottom water result in summer and fall releases of hydrogen sulfide and fish kills. The salinity of the Sea is 47 g/L and rising, with an annual salt load of 4 million metric tons. Plans are being developed for construction of a salt repository to control salinization, improve water quality, and maintain the Sea as a refuge for migratory waterfowl. We estimate 700,000 metric tons of calcite are precipitating in the Sea each year, along with 7,000 tons of iron sulfide minerals. Potentially, 70,000 metric tons of hydrogen sulfide are produced in the Sea each year. Measurements of hydrogen sulfide production, reoxidation in the water column, and atmospheric releases will be reported. Hydrodynamic modeling of the current Sea, and the proposed smaller Sea, indicate that partitioning the Sea could lead to persistent stratification and episodic releases of hydrogen sulfide during fall mixing.

Amrhein, C.; Reese, B. K.; Anderson, M. A.

2006-12-01

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

ALKYLPHENOLS, POLYCYCLIC AROMATIC HYDROCARBONS, AND ORGANOCHLORINES IN SEDIMENT FROM LAKE SHIHWA, KOREA:INSTRUMENTAL AND BIOANALYTICAL CHARACTERIZATION  

Microsoft Academic Search

AbstractLake Shihwa is an artificial lake, located on the west coast of Korea, that has experienced environmental deterioration since 1994, when it was formed by construction of a sea dike. This study used instrumental analysis and in vitro bioassays to characterize organic,contaminants,in sediment,collected from,11 stations on Lake Shihwa. Alkylphenol,(AP) concentrations,in Lake Shihwa sediment ranged from 20.2 to 1,820 ng\\/g nonylphenol

Jong Seong Khim; Daniel L. Villeneuve; Kurunthachalam Kannan; Kyu Tae Lee; Shane A. Snyder; Chul-Hwan Koh; John P. Giesy

1999-01-01

280

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

281

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

282

Hazardous crater lakes studied  

Microsoft Academic Search

Crater lakes usually sit on top of volcanic conduits and act as condensers of magmatic vapor. Studies of crater lakes can therefore provide information on both deep magmatic activity and variations in the degassing state of a shallow magmatic body. The Lake Nyos gas disaster of August 1986 and a similar event in August 1984 at Lake Monoun, both in

Minoru Kusakabe

1993-01-01

283

Technologies for lake restoration  

Microsoft Academic Search

Lakes are suffering from different stress factors and need to be restored using different approaches. The eutrophication remains as the main water quality management problem for inland waters: both lakes and reservoirs. The way to curb the degradation is to stop the nutrient sources and to accelerate the restoration with help of in-lake technologies. Especially lakes with a long retention

Helmut KLAPPER

2003-01-01

284

Karst system developed in salt layers of the Lisan Peninsula, Dead Sea, Jordan  

Microsoft Academic Search

The Lisan Peninsula, Jordan, is a massive salt layer accumulated in the inner part of the Dead Seas precursory lakes. This\\u000a tongue-shaped, emergent land results in a salt diapir uplifted in the Dead Sea strike-slip regional stress field and modified\\u000a by the water level fluctuations of the last lake during the Holocene. These two elements, associated with dissolution caused\\u000a by

Damien Closson; Philip E. LaMoreaux; Najib Abou Karaki; Hassan al-Fugha

2007-01-01

285

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

286

Rediscovery of lake balls in Lake Michigan  

USGS Publications Warehouse

For the first time in 70 years, the occurrence of a 'lake ball' in Lake Michigan is here reported in the literature. According to a published system of classification, the object we collected in 1978 was a 'false' lake ball. Dissection revealed that it was colonized by 5 chironomid larvae and 162 oligochaetes. The species and numerical proportions of the oligochaetes indicated that it was formed in or near the mouth of a eutrophic tributary rather than in the open waters of Lake Michigan where it was found. Because of their mobility, false lake balls may be ecologically important, serving as natural vehicles for the dispersal of invertebrates.

Schloesser, Donald W.; Hiltunen, Jarl K.; Owens, Randall W.

1983-01-01

287

The Lakes of Canada  

NSDL National Science Digital Library

This information about Canadian lakes includes a general overview of the lakes, which are divided into four quadrants. In each area the origins and general characteristics of the lakes are discussed. The site also features an interactive map. At each lake location there is information on the physical attributes, general description, and watershed of the lake. Four additional chapters contain detailed information, which distinguishes lakes from other aquatic environments, explains the mechanisms by which lakes in Canada were created, discusses lake morphology, distribution of light and heat, and water movement, and discusses seasonal distribution as well as variations in distribution and concentration of oxygen. Aspects of nitrogen, phosphorus, and organic carbon cycling that pertain to lakes are addressed. In addition, one chapter provides statistical facts about different Canadian lakes.

288

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

289

Two Antarctic desert lakes  

Microsoft Academic Search

The optical and biological propertics of ice-covcrcd Lakes Vanda and Bonncy, Antarctica, were observed during two austral summers. The lakes arc among the clearest known, with extinction coefficients as low as 0.031 for blue light in Lake Vanda and 0.069 for green light in Lake Bonney. Temperature and conductivity measurements in a shallow lake on Cape Evans, Antarctica, suggest a

CHARLES R. GOLDMAN; DAVID T. MASON; JOHN E. HOBBIE

1967-01-01

290

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

291

Restoring the Shrinking Dead Sea The Environmental Imperative  

Microsoft Academic Search

The Dead Sea is a part of the Jordan Rift Valley (JRV) which extends for more than 400 km from Lake Tiberias in the north to the Gulf of Aqaba in the south and includes the Jordan River Valley, the Dead Sea (DS) and Wadi Araba. Its unique climatic conditions, its good soils, availability of water and irrigation form a

Elias Salameh; Hazim El-Naser

292

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

293

Remote sensing of the Dead Sea surface temperature  

Microsoft Academic Search

The Dead Sea is a unique terminal lake located at the lowest place on Earth's surface. It has the highest surface temperature, salinity, and density among Earth's large water bodies, and its level is currently dropping at a rate of ?1 m\\/a. Knowledge of the Dead Sea thermal and saline structure is based on meteorological and hydrological measurements from a

R. Nehorai; I. M. Lensky; N. G. Lensky; S. Shiff

2009-01-01

294

Remote sensing of the Dead Sea surface temperature  

Microsoft Academic Search

The Dead Sea is a unique terminal lake located at the lowest place on Earth's surface. It has the highest surface temperature, salinity, and density among Earth's large water bodies, and its level is currently dropping at a rate of 1 m\\/a. Knowledge of the Dead Sea thermal and saline structure is based on meteorological and hydrological measurements from a

R. Nehorai; I. M. Lensky; N. G. Lensky; S. Shiff

2009-01-01

295

Dynamics of the carbon dioxide system in the Dead Sea  

Microsoft Academic Search

Because the Dead Sea is a Ca-chloride hypersaline lake and is virtually lifeless, it is an excellent system to investigate the physical and chemical paths of the carbon cycle in terrestrial aquatic environments that are generally overwhelmed by biologic carbon fluxes. The Dead Sea is known to form massive aragonite deposits in the form of varves at present and during

Eugeni Barkan; Boaz Luz; Boaz Lazar

2001-01-01

296

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 ...

297

The U.S. Great Lakes Commercial Fishing Industry--Past, Present, and Potential.  

National Technical Information Service (NTIS)

Overfishing, predators (sea lamprey), contaminants and increasingly restrictive state regulations have reduced the U.S. Great Lakes commercial fishing industry to a mere shadow of its former prominence. At this time there is little chance that the number ...

1977-01-01

298

Assessing Assessment: Can the Expected Effects of the St. Marys River Sea Lamprey Control Strategy Be Detected?  

Microsoft Academic Search

In 1997 the Great Lakes Fishery Commission approved a 5-year (1998 to 2002) control strategy to reduce sea lamprey (Petromyzon marinus) production in the St. Marys River, the primary source of parasitic sea lampreys in northern Lake Huron. An assessment plan was developed to measure the success of the control strategy and decide on subsequent control efforts. The expected effects

Jean V. Adams; Roger A. Bergstedt; Gavin C. Christie; Douglas W. Cuddy; Michael F. Fodale; John W. Heinrich; Michael L. Jones; Rodney B. McDonald; Katherine M. Mullett; Robert J. Young

2003-01-01

299

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

Microsoft Academic Search

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

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

2009-01-01

300

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

301

Holocene trophic state history of a subtropical blackwater lake, South Georgia, USA  

Microsoft Academic Search

Organic-rich sediment from Lake Louise, a dystrophic sinkhole lake in south Georgia, displays variations in C, N, P, C\\/N,\\u000a ?13C, ?15N, biogenic silica (BSi) and diatom flora that document changes in trophic state over the past~9,500 years. The lake initially\\u000a was oligotrophic and moderately productive, but by the middle Holocene a rising regional water table, driven by eustatic sea\\u000a level

Jeffrey H. TepperJames; James A. Hyatt

2011-01-01

302

Palaeohydrological significance of late Quaternary strontium isotope ratios in a tropical lake  

Microsoft Academic Search

Ostracods preserved in late Quaternary sediments of Wallywash Great Pond, a fresh coastal lake in SW Jamaica, record temporal variations in the strontium-isotope composition of lake water. Oxygen-isotope and Sr\\/Ca ratios in ostracods reveal temporal variations in the lake's hydrology, related to effective precipitation, and in its salinity related to varying marine-saline groundwater input from changes in relative sea level.

J. A. Holmes; D. P. F. Darbyshire; T. H. E. Heaton

2007-01-01

303

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

304

Vertical distribution and rotifer concentrations in the chemocline of meromictic lakes  

Microsoft Academic Search

The vertical distribution of planktonic rotifers has been analysed in relation to season in several meromictic lakes; a coastal lagoon with sea-water intrusion and three dissolution lakes from two karstic systems. Two species, Filinia hofmanni and a form of Anuraeopsis fissa have been found to be more or less restricted to the chemocline or adjacent strata any time they occurred.

Mara R. Miracle; Eduardo Vicente

1983-01-01

305

Tracing the sources of PCDD\\/Fs and PCBs in Lake Baikal  

Microsoft Academic Search

Lake Baikal is a unique freshwater ecosystem that has been declared a UNESCO World Heritage Site. It contains high levels of PCBs, and Baikal seal were recently found to have PCDD\\/F concentrations comparable to those in the Baltic Sea. In this work fish and soil were analyzed to trace the sources of these compounds to the lake. The fish samples

Alexander A. Mamontov; Elena A. Mamontova; Evgenia N. Tarasova; Michael S. McLachlan

2000-01-01

306

Oceanography of a tidally choked fjord: Lake Melville, Labrador  

NASA Astrophysics Data System (ADS)

Lake Melville is large and complex sub-Arctic fjord that is a major outlet for freshwater on the Labrador coast. Although it has been the subject of exploration for centuries, we still know relatively little about its oceanography. We are studying the influence of changes in the fresh water discharge on the dynamics and ecosystem of Lake Melville in Labrador and how they interact with long-term climatic variability. Enormous hydroelectric developments have changed the freshwater runoff dynamics with unknown implications for the local and regional oceanography. The fjord is tidally choked, leading to intense flows at the entrance of 3-4 m/s. We will review the role of mixing and seasonal cycles in determining water properties in the lake and how changing climatic and freshwater conditions influence the oceanography and sea-ice dynamics. We will present historical data for the Lake together with results from our recent oceanographic work. We will compare our current measurements with results of a high resolution, variable element, coupled ocean-ice model for the Lake. The long-term exchange between the Labrador Sea and Lake Melville will be studied with this high-resolution ocean model. The implications of interannual ocean and atmospheric variability on the Lake ocean ecosystem will be discussed.

deYoung, Brad; Lu, Zhaoshi; Demirov, Entcho

2013-04-01

307

Temporal and spatial variability of Great Lakes ice cover, 1973-2010  

NASA Astrophysics Data System (ADS)

This study examines temporal and spatial variability of ice cover in the Great Lakes using historical satellite measurements from 1973 to 2010. The seasonal cycle of ice cover was constructed for all the lakes including Lake St. Clair. A unique feature found in the seasonal cycle is that the standard deviations (i.e., variability) of ice cover are larger than the climatological means for all the lakes. This indicates that Great Lakes ice cover experiences large variability in response to predominant natural internal climate forcing and has poor predictability. Spectral analysis shows that lake ice has both quasi-decadal and interannual time scales of ~8 years and ~4 years. There was a significant downward trend from 1973 to the present for all the lakes, with Lake Ontario having the largest, and Lakes Erie and St. Clair having the smallest. An EOF (empirical orthogonal function) analysis indicates that a major response of ice cover to atmospheric forcing is in phase in all six lakes, accounting for 80.8% of the total variance. The second mode shows an out-of-phase spatial variability between the Upper Lakes and Lower Lakes, accounting for 10.7% of the total variance. The regression of the first EOF-mode time series to sea level pressure, surface air temperature, and surface wind shows that lake ice mainly responds to the combined AO (Arctic Oscillation) and ENSO (El Nino and Southern Oscillation) patterns.

Wang, J.; Bai, X.; Hu, H.; Clites, A.; Colton, M. C.; Lofgren, B. M.

2011-12-01

308

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

309

Thermal regimes of Florida lakes  

Microsoft Academic Search

Water column temperatures were determined monthly for 24 lakes and bimonthly for 5 lakes in peninsular Florida during 1979. Three geographical groups (north, central, south) were delineated from mean monthly water column temperatures for individual lakes. On a monthly basis, northern lakes were least similar to southern lakes, while central Florida lakes displayed greater affinity to the southern than to

John R. Beaver; Thomas L. Crisman; James S. Bays

1981-01-01

310

Abundance of picophytoplankton in the halocline of a meromictic lake, Lake Suigetsu, Japan  

Microsoft Academic Search

Numerous (0.5 to 4.8 105 cells\\/ml), small phytoplankton (smaller than 0.51 12 ?m in cell size, picophytoplankton) were distributed in the halocline\\u000a (depth 212 m, 414 practical salinity units) of the saline meromictic lake, Lake Suigetsu (3535? N, 13552? E), located\\u000a in the central part of the coast of Wakasa Bay along the Japan Sea in Fukui Prefecture,

Mari Okada; Yukiko Taniuchi; Akio Murakami; Shinichi Takaichi; Shinya Ohtake; Kaori Ohki

2007-01-01

311

Treatment of East Bay, Alger County, Michigan, with toxaphene for control of sea lampreys  

USGS Publications Warehouse

An experiment was conducted to determine whether toxaphene can be used to eradicate lake-dwelling sea lampreys and to determine its effect on fish populations. In East Bay, a 78-acre lake on the Sucker River, Alger County, Mich., an estimated concentration of 100 parts per billion was maintained for 14 days. The sea lamprey larvae were more resistant to toxaphene than were the fish, but a complete kill was indicated. One year after treatment, sea lampreys were absent from the lake, while the fish population had recovered.

Gaylord, William E.; Smith, Bernard R.

1966-01-01

312

Sea Grant Nonindigeneous Species Site  

NSDL National Science Digital Library

The National Sea Grant College Program, in conjunction with the Great Lakes Sea Grant Network, has recently launched the Sea Grant Nonindigenous Species Site (SGNIS). Intended to serve as a national information center, SGNIS is structured as a database and provides "a comprehensive collection of research publications and education materials ... on zebra mussels and other aquatic nuisance species." The database is searchable by Title, Authors, Organization, Date of publication, or Keywords (subject), and typical returns provide hyperlinks to abstracts, and in come cases, the full text (.pdf format) of published articles. In addition to the publications listed here, a selection of external links points users to additional sites. This is an excellent resource, well conceived and up to date.

313

Lake Barkley Regional Plan.  

National Technical Information Service (NTIS)

The Lake Barkley Regional Plan includes (a) land use recommendations for the unincorporated portions of Lyon and Trigg Counties affected by the Lake, (b) seperate recommendations for revisions to the Cadiz General Plan, (c) recommendations for coordinatio...

D. P. Fogle

1965-01-01

314

The Pantanal lakes  

Microsoft Academic Search

\\u000a More than anything else, the Pantanal is a land of lakes. There exists no census, but a prudent estimate would put the number\\u000a of lakes in the tens of thousands. Most of them are small lakes of 500 to 1000 m diameter. On the lands of one farm alone\\u000a (Fazenda Nhumirim), there are some 100 such small lakes (Mouro et

F. D. Por

315

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

316

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

317

Quantifying anoxia in lakes  

Microsoft Academic Search

The anoxic factor (AF, days per year or per season) can be used to quantify anoxia in stratified lakes. AF is calculated from oxygen profiles measured in the stratified season and lake surface area (A,) as AF represents the number of days that a sediment area, equal to the whole-lake surface area, is overlain by anoxic water. Average AF for

Gertrud K. Niirnberg

1995-01-01

318

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.

319

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

Horvath, Thomas

2005-01-01

320

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

321

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.

322

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

323

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

324

The second population of Arctic charr Salvelinus alpinus complex (Salmoniformes, Salmonidae) in the Lake Baikal basin, the highest mountain charr population in Russia  

Microsoft Academic Search

We report the finding of the second population of Arctic charr in Lake Baikal basin, in a nameless lake in the Barguzin mountain\\u000a range in the outlet of the Svetlaya River. The lake is situated at an altitude of 1766 m above sea level; this is the highest\\u000a lake inhabited by this species in the territory of Russia. Two abundant

V. P. Samusenok; S. S. Alekseyev; A. N. Matveev; N. V. Gordeeva; A. L. Yurev; A. I. Vokin

2006-01-01

325

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.

326

Effects of Repeated TFM Applications on Riffle Macroinvertebrate Communities in Four Great Lakes Tributaries  

Microsoft Academic Search

As part of the sea lamprey control program in the Great Lakes, a suite of about 150 sea lamprey producing streams have been regularly treated with the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) every 3 to 5 years since 1958. State, provincial, and tribal agencies in the basin supported the use of TFM and urged that the risk to nontarget organisms be minimized.

John W. Weisser; Jean V. Adams; Richard J. Schuldt; Gregg A. Baldwin; Dennis S. Lavis; Jeffrey W. Slade; John W. Heinrich

2003-01-01

327

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

328

Hazardous crater lakes studied  

NASA Astrophysics Data System (ADS)

Crater lakes usually sit on top of volcanic conduits and act as condensers of magmatic vapor. Studies of crater lakes can therefore provide information on both deep magmatic activity and variations in the degassing state of a shallow magmatic body. The Lake Nyos gas disaster of August 1986 and a similar event in August 1984 at Lake Monoun, both in Cameroon, resulted from the accumulation of magmatic CO2 in the bottom layers of the lakes. Geochemical monitoring of crater lakes is a promising tool for forecasting not only limnic but also volcanic eruptions. Acid-mineralized waters formed by condensation of hot magmatic volatiles in crater lakes are thought to bear some resemblance to hydrothermal fluids acting in the genesis of acid-sulfate alteration and Au-Cu-Ag mineralization of volcanic-hosted precious metal deposits.

Kusakabe, Minoru

329

Water quality of Lake Austin and Town Lake, Austin, Texas  

SciTech Connect

Lake Austin and Town Lake are impoundments on the Colorado River in Travis County, central Texas, and are a source of water for municipal industrial water supplies, electrical-power generation, and recreation for more than 500,000 people in the Austin metropolitan area. Small vertical temperature variations in both lakes were attributed to shallow depths in the lakes and short retention times of water in the lakes during the summer months. The largest areal variations in dissolved oxygen generally occur in Lake Austin during the summer as a result of releases of water from below the thermocline in Lake Travis. Except for iron, manganese, and mercury, dissolved concentrations of trace elements in water collected from Lake Austin and Town Lake did not exceed the primary or secondary drinking water standards set by the US Environmental Protection Agency. Little or no effect of stormwater runoff on temperature, dissolved oxygen, or minor elements could be detected in either Lake Austin or Town Lake. Little seasonal or areal variation was noted in nitrogen concentrations in Lake Austin or Town lake. Total phosphorus concentrations generally were small in both lakes. Increased concentrations of nitrogen and phosphorus were detected after storm runoff inflow in Town Lake, but not in Lake Austin; densities of fecal-coliform bacteria increased in Lake Austin and Town Lake, but were substantially greater in Town Lake than in Lake Austin. 18 refs., 38 figs., 59 tabs.

Andrews, F.L.; Wells, F.C.; Shelby, W.J.; McPherson, E.M.

1988-01-01

330

Primary producer dynamics associated with evaporative concentration in a shallow, equatorial soda lake (Lake Elmenteita, Kenya)  

Microsoft Academic Search

Lake Elmenteita (027'S, 3615'E) lies on the floor of the rift valley at 1776 m above sea level in Kenya. As a consequence of lower than average rainfall, the mean depth decreased from 1.1 to 0.65 m during the study period (February 1973 to August 1974). The initiation of major biological changes coincided with a period of rapid evaporative concentration

John M. Melack

1988-01-01

331

Changes of sea level, landscape and culture: A review of the south-western Baltic area between 8800 and 4000 BC  

Microsoft Academic Search

The global warming at the end of the last glacial period led to a sea level rise, which induced substantial long-term landscape changes in the southwestern Baltic Sea. During the Preboreal and Boreal periods, this region, bordering on the Ancylus Lake in the east, was dry land with numerous lakes and rivers. However, with the beginning of the Littorina Transgression

Ulrich Schmlcke; Elisabeth Endtmann; Stefanie Klooss; Michael Meyer; Dierk Michaelis; Bjrn-Henning Rickert; Doreen Rler

2006-01-01

332

Sea turtles  

Microsoft Academic Search

odern sea turtles are an important component of a wide range of tropical, temperate, and cold water marine ecosystems . Their inclusion on various lists of endangered specie s reflects past over-exploitation and the current need for better management . Today, seven or eight species of sea turtles are recognised, in two families and six genera. Adults typically migrate between

Catherine M. F. Lohmann; Kenneth J. Lohmann

2006-01-01

333

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

334

Modeling Mesoscale Diffusion and Transport Processes for Releases Within Coastal Zones during Land/Sea Breezes.  

National Technical Information Service (NTIS)

This document discusses the impacts of coastal mesoscale regimes (CMRs) upon the transport and diffusion of potential accidental radionuclide releases from a shoreling nuclear power plant. Case studies illustrate land breezes, sea/lake breeze inflows and ...

C. S. Keen J. A. Schuh W. A. Lyons

1983-01-01

335

Simulering av TNT-Laeckage i Havsmiljoe (Simulation of TNT Leakage in Sea Environment).  

National Technical Information Service (NTIS)

After World War II, since no destruction plant for explosives was available, explosives were dumped in various places in Sweden. Between 1940 and 1968 munitions were dumped in lakes, abounded mineshafts and sea area. Presently, the Swedish Armed Forces is...

A. C. Andersson J. Eriksson L. Haegglund Y. Nygren T. Johansson

2001-01-01

336

Integrated analysis of magnetic, paleomagnetic and KAr data in a tectonic complex region: An example from the Sea of Galilee  

Microsoft Academic Search

Sea of Galilee (Lake Kinneret) is located in northern Israel in the area of complex tectonic setting where the Dead Sea Transform crosscuts other fault systems. Practical absence of wells in the sea hinders geological-geophysical data interpretation. Map of the total magnetic field shows an intricate pattern of the magnetic field distribution caused by a combined influence of the basalt

Lev Eppelbaum; Zvi Ben-Avraham; Youri Katz

2004-01-01

337

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

338

Large Lake Sampling Program Assessment Report for Leech Lake, 1995.  

National Technical Information Service (NTIS)

The Large Lake Monitoring Program was implemented to monitor and evaluate fish populations within Minnesota's large walleye lakes. For Leech Lake, this program includes annual fish population monitoring, natural reproduction checks, water quality monitori...

N. A. Haukos

1995-01-01

339

14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.  

Code of Federal Regulations, 2010 CFR

... false Special requirements, Lake Campbell and Sixmile Lake Airports. 93.69...93.69 Special requirements, Lake Campbell and Sixmile Lake Airports. Each person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall...

2010-01-01

340

14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.  

Code of Federal Regulations, 2010 CFR

... false Special requirements, Lake Campbell and Sixmile Lake Airports. 93.69...93.69 Special requirements, Lake Campbell and Sixmile Lake Airports. Each person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall...

2009-01-01

341

Tyee Lake project: Alaska's second lake tap  

SciTech Connect

Environmentally, as well as in terms of pure water energy efficiency, lake taps are an ideal source of power. The basic concept is to tap into the bottom of a high mountain lake to use the high static head of water to spin turns. The Lake Tyee project starts with a tunnel at the lowest possible topographic point and uses the elevation differential between the lake bottom and originating point of the tunnel to multiply the height of the hydrostatic head. The water will generate 20 MW with a capacity to take on another 10-MW generator. The power generating system will be concealed inside the mountain with a small powerhouse and tail race visible. The cost of the project was over $60 million.

Sieber, O.V.

1983-12-01

342

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

343

Resistance to 3-trifluoromethyl-4-nitrophenol (TFM) in sea lamprey  

USGS Publications Warehouse

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) has been used in the United States and Canada for more than 30 years to control populations of sea lamprey (Petromyzon marinus) in the Great Lakes. There is concern that sea lamprey might become resistant to TFM. Lampricide toxicity tests have been conducted at the Hammond Bay Biological Station, Millersburg, Michigan, since the 1950s and examination of TFM toxicity data for larval lamprey from 1963 to 1987 indicated that sea lamprey have not developed increased resistance to TFM. Maintenance of current control practices are unlikely to cause the development of TFM-resistant sea lamprey strains in the foreseeable future.

Scholefield, R. J.; Seelye, J. G.

1990-01-01

344

Is Lake Prespa Jeopardizing the Ecosystem of Ancient Lake Ohrid?  

Microsoft Academic Search

Lake Prespa and Lake Ohrid, located in south-eastern Europe, are two lakes of extraordinary ecological value. Although the\\u000a upstream Lake Prespa has no surface outflow, its waters reach the 160m lower Lake Ohrid through underground hydraulic connections.\\u000a Substantial conservation efforts concentrate on oligotrophic downstream Lake Ohrid, which is famous for its large number of\\u000a endemic and relict species. In this

A. Matzinger; M. Jordanoski; E. Veljanoska-Sarafiloska; M. Sturm; B. Mller; A. West

2006-01-01

345

Illinois-Indiana Sea Grant K-12 Education Resources  

NSDL National Science Digital Library

This collection of Illinois-Indiana Sea Grant education resources includes several activities that introduce students to invasive species and seafood contamination. The goal of these activities is to educate not only students but adults on the issues of the Great Lakes. These resources also offer a multi-disciplinary approach to learning by integrating science with content areas such as math, language arts, geography, and the cultural arts. Resources are applicable to regions outside the Great Lakes.

346

Artificial propagation of the sea lamprey Petromyzon marinus  

USGS Publications Warehouse

Observations on the gland products, gonads, and general characteristics of sexually mature sea lampreys, Petromyzon marinus (Linnaeus), from Lake Huron, and a need to obtain some information on very young larval lampreys, prompted an experiment on the stripping and hatching of eggs. Seventeen specimens were selected from a group of spawning migrants which had been trapped in the Ocqueoc River, Michigan, during June and held in live-cars in the lake until early August.

Lennon, Robert E.

1955-01-01

347

Is There a Paleolimnological Explanation for Walking on Water in the Sea of Galilee?  

Microsoft Academic Search

Lake Kinneret (the Sea of Galilee) is a small freshwater lake (148km2 and a mean depth of 20m) situated in northern Israel. Throughout recent history there have been no known records of a total\\u000a ice formation on its top. Furthermore, given that convection requires an initial cooling of the entire lake down to 4C,\\u000a it is difficult to imagine how

Doron Nof; Ian McKeague; Nathan Paldor

2006-01-01

348

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

349

The Lake Peten-Itza (Guatemala) Drilling Project: Tracking Late Quaternary Environmental Change in the Lowland Neotropics  

Microsoft Academic Search

During the last glaciation, all shallow lake basins in the northern lowland Neotropics were dry because of increased aridity and\\/or lowered sea level Consequently, no long continous paleoclimate records have yet to be recovered from this climatically sensitive region. Detailed seismic surveys of Lake Peten-Itza have revealed that Lake Peten-Itza is deep (160 m) and possesses a thick (>100 m)

F. S. Anselmetti; D. A. Hodell; D. Ariztegui; M. Brenner; J. H. Curtis; G. Haug; M. Hillesheim; J. A. McKenzie

2004-01-01

350

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

351

Human Effects on Varna-Beloslav Lake Complex and Detection of Long-Term Changes  

NASA Astrophysics Data System (ADS)

There are several larger lakes at the 412 km long Bulgarian Black Sea coastline, as each distinguishes with a specific hydrological regime and parameters. The deepest and the largest is the Varna Lake, located west from the Bay of Varna at the North Bulgarian coast. The lake is a firth formation at the river valley under a rising sea level during the Holocene, when it was divided from the sea by a large sandy spit. In 1900s with construction of Varna Port a navigational channel between Varna Lake and the sea was built, while in 1920s it was artificially connected to the inland Beloslav Lake by other navigational channel. Since the beginning of the past century the both lakes have been subject of many direct human impacts, such as: digging of three navigational channels; situating a number of ports with different functions; constantly performed dredging activities etc. The aim of this study was to trace the long-term changes to the lakes of Varna and Beloslav mostly related to human activities over a 100-year period. Two types of data were used: historical topographic map from 1910 in scale 1:200 000 and nautical maps in scale 1:10 000 from 1994. The data were processed and analysed with support of GIS and modelling in order to quantify the changes of areas and volumes of the lakes, as well as of the navigational channel between them. The findings from the study clearly reveal significant alterations of the two lakes that have been caused by increased anthropogenic impacts over the whole past century. Irreversible changes and modifications of the lakes features and coastal section around, as well as alterations of the areas and hydrological regime of the whole lake system were identified. In order to evaluate the anthropogenic impacts a coastline segmentation of the study area was performed as the lengths of natural and armoured coasts were determined. This in turn allowed finding the extent of technogenous occupation of the coast: 11107 m or about 24% from the total 46112 m long lakes coastline were armoured. Adding also two navigational channels having a total length of 8500 m, then the length of the technogenous coast has reached up to 42 %. In relation with required maintenance of the safe shipping depth and following permanent dredging works, it is suggests the examined Varna-Beloslav Lake system would experience continuative impacts and negative effects. At present, a new project for replacement of the Varna Port East to the northernmost part of the Varna Lake has been operating and this would suppose additional dredging activities leading to new changes of the coastline and bottom features of both lakes.

Palazov, Atanas; Stanchev, Hristo; Stancheva, Margarita

2013-04-01

352

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

353

Great Lakes Monthly Hydrologic Data.  

National Technical Information Service (NTIS)

Accurate hydrologic data (over-land precipitation, over-lake precipitation, runoff, lake evaporation, net basin supplies, connecting channel flows, diversion flows, beginning-of-month lake levels, and changes in storage) are required for simulation, forec...

T. E. Croley T. S. Hunter

1994-01-01

354

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

355

Great Lakes water levels  

Microsoft Academic Search

A new publication, Great Lakes Water Levels, 1860-1970, has been issued by the Lakes Survey Center of the National Oceanic and Atmospheric Administration. \\u000a\\u000aThe book contains tabular records of monthly and annual average water surface elevations for each of the more than 50 permanent gages in the Lake Survey network. There are also summaries of the average and extreme levels

Anonymous

1971-01-01

356

Big lake records preserved in a little lakes sediment: an example from Silver Lake, Michigan, USA  

Microsoft Academic Search

We reconstruct postglacial lake-level history within the Lake Michigan basin using soil stratigraphy, ground-penetrating radar\\u000a (GPR), sedimentology and 14C data from the Silver Lake basin, which lies adjacent to Lake Michigan. Stratigraphy in nine vibracores recovered from the\\u000a floor of Silver Lake appears to reflect fluctuation of water levels in the Lake Michigan basin. Aeolian activity within the\\u000a study area

Timothy G. Fisher; Walter L. Loope; William Pierce; Harry M. Jol

2007-01-01

357

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

358

Sea Legs  

NASA Astrophysics Data System (ADS)

Forty-foot, storm-swept seas, Spitzbergen polar bears roaming vast expanses of Arctic ice, furtive exchanges of forbidden manuscripts in Cold War Moscow, the New York city fashion scene, diving in mini-subs to the sea floor hot srings, life with the astronauts, romance and heartbreak, and invading the last bastions of male exclusivity: all are present in this fast-moving, non-fiction account of one woman' fascinating adventures in the world of marine geology and oceanography.

Macdonald, Kenneth C.

359

Virus-host interactions in salt lakes.  

PubMed

Natural hypersaline waters are widely distributed around the globe, as both continental surface waters and sea floor lakes, the latter being maintained by the large density difference between the hypersaline and overlying marine water. Owing to the extreme salt concentrations, close to or at saturation (approximately 35%, w/v), such waters might be expected to be devoid of life but, in fact, maintain dense populations of microbes. The majority of these microorganisms are halophilic prokaryotes belonging to the Domain Archaea, 'haloarchaea'. Viruses infecting haloarchaea are a vital part of hypersaline ecosystems, in many circumstances outnumbering cells by 10-100-fold. However, few of these 'haloviruses' have been isolated and even fewer have been characterised in molecular detail. In this review, we explore the methods used by haloviruses to replicate within their hosts and consider the implications of haloviral-haloarchaeal interactions for salt lake ecology. PMID:17714980

Porter, Kate; Russ, Brendan E; Dyall-Smith, Michael L

2007-08-21

360

Valley network-fed, open-basin lakes on Mars: Distribution and implications for Noachian surface and subsurface hydrology  

NASA Astrophysics Data System (ADS)

A new catalog of 210 open-basin lakes (lakes with outlet valleys) fed by valley networks shows that they are widely distributed in the Noachian uplands of Mars. In order for an outlet valley to form, water must have ponded in the basin to at least the level of the outlet. We use this relationship and the present topography to directly estimate the minimum amount of water necessary to flood these basins in the past. The volumes derived for the largest lakes (310 to 210 km) are comparable to the largest lakes and small seas on modern Earth, such as the Caspian Sea, Black Sea, and Lake Baikal. We determine a variety of other morphometric properties of these lakes and their catchments (lake area, mean depth, volume, shoreline development, outlet elevation, and watershed area). Most candidate lakes have volumes proportional to and commensurate with their watershed area, consistent with precipitation as their primary source. However, other lakes have volumes that are anomalously large relative to their watershed areas, implying that groundwater may have been important in their filling. Candidate groundwater-sourced lakes are generally concentrated in the Arabia Terra region but also include the Eridania basin [Irwin, R.P., Howard, A.D., Maxwell, T.A., 2004a. J. Geophys. Res. 109, doi: 10.1029/2004JE002287. E12009; Irwin, R.P., Watters, T.R., Howard, A.D. Zimbelman, J.R., 2004b. J. Geophys. Res. 109, doi: 10.1029/2004JE002248. E09011] and several lakes near the dichotomy boundary. This areal distribution is broadly consistent with where groundwater should have reached the surface as predicted by current models. Both surface runoff and groundwater flow appear to have been important sources for lakes and lake chains, suggesting a vertically integrated hydrological system, the absence of a global cryosphere, and direct communication between the surface and subsurface hydrosphere of early Mars.

Fassett, Caleb I.; Head, James W.

2008-11-01

361

Returns of hatchery-reared lake trout in southern Lake Superior, 1955-62  

USGS Publications Warehouse

Experimental plantings of fin-clipped lake trout (Salvelinus namaycush) of various ages have been made in southern Lake Superior since 1952. The catch of planted lake trout by the commercial fishery was used to measure the success of stocking. Estimates of total returns were based on samples of 8.2 to 21.2% of the Wisconsin catches in 1955-62 and 36.4 to 46.8% of the Michigan catches in 1959-62. Marked lake trout were assigned to various plantings according to the fin mark, length of fish, readings of age from scales, and locations of capture. Estimated returns from Wisconsin plantings of 9-month-old lake trout varied from 2.1 to 6.4%. Wisconsin releases of 16-month-old fish yielded returns of 5.7 to 37.3%. Returns from plantings in Michigan were 0.3% for 9-month-old fish and 1.5 to 3.8% for 16-month-old fish. The ratios of the returns from plantings of 16-month-old fish to those of 9-month-old fish were 3.9:1 for Wisconsin releases and 6.7:1 for Michigan releases. Lake trout planted in Wisconsin generally survived better than those released in Michigan. Returns from fish planted at ages of 17 to 40 months in Michigan in 1958-59 were far greater than those from 16-month-old fish released in Michigan, but were not as high as from the most successful plantings of 16-month-old fish in Wisconsin. Lake trout released in 1960 from shore and from boats survived equally well. Average size of lake trout at release was more closely related to survival than any other factor. All except 1 of 10 highly successful releases were of fish larger than 22 per lb, and all 6 poor releases were of fish smaller than 34 per lb. Fish that ran 22 to 33 per lb survived only moderately well. A size of 17 to 20 fish per lb appears to be close to optimum. Abundance of native lake trout, American smelt (Osmerus mordax), and sea lampreys (Petromyzon marinus) all appeared to be unrelated to stocking success. The only apparent method of rapidly improving the success of stocking is to rear all lake trout to an average size of 17 to 20 per lb.

Pycha, Richard L.; King, George R.

1967-01-01

362

Seismic investigation of Lake Issyk-Kul, Kyrgyzstan  

NASA Astrophysics Data System (ADS)

Lake Issyk-Kul is located in an intramontane basin of the Tien Shan mountains in Kyrgyzstan, Central Asia. It has formed in a tectonically active region with W-E striking major thrust zones north and south of the lake. The lake's modern surface level is at 1607 m above sea level, maximum depth in the central basin of the lake is roughly 670 m, and the total water volume is around 1736 km3. The lake is elongated with 180 km in west-east and 60 km in south-north direction. With a surface area of 6232 km2, Lake Issyk-Kul is the second largest lake in the higher altitudes. The lake is characterized by two large delta areas at its western and eastern end, with the deltaic area being as wide as up to 60 km in the eastern and 40 km in the western part, and by steep slopes at the northern and southern shore with only a rather narrow shallower shelf area. The lake contains the sediments of the past up to several million years, and has been proposed as a future target for deep drilling within ICDP. Three seismic surveys by Russian and Belgian groups in 1982, 1997 and 2001 revealed a thick sediment infill in Lake Issyk-Kul. At both the western and the eastern end of the lake, large delta systems were formed by actual and previous inlets, namely the Tyup and Djyrgalan rivers in the eastern part of the lake (still active) and the Chu River at the western end (currently bypassing the lake). Large sub-aquatic channel systems are visible in the lake's bathymetry in the shallower part of the delta systems close to the river mouths. They were quite likely formed by these rivers during a former lake level lowstand. The delta system consists of stacked prograding delta lobes with a characteristic topset-foreset-bottomset configuration. These lobes together with sub-aerial terraces found at several spots around the lake witness lake level fluctuations of up to >400 m. The sediments in the central plain of Lake Issyk-Kul are mainly well-layered with many turbiditic sequences intercalated with pelagic background sedimentation. Sediments are slightly inclined towards south with increasing angles with depth, suggesting a halfgraben structure of the lake basin. Mass transport deposits such as debris flows are a common feature close to the steeper flanks around the central plain. The southern flank is characterized by many small terraces and several canyons that are related to the small inlets at the southern shore. The northern flank, however, shows a small, shallow shelf area of 25 to 30 m water depth. This area is characterized by glacial outwash sediments brought to the lake by small rivers that drain the large terminal moraines which are located north of the lake.

Gebhardt, C.; Naudts, L.; De Mol, L.; De Batist, M.

2012-04-01

363

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.

364

Cyanide Soap? Dissolved material in Titan's Seas  

NASA Astrophysics Data System (ADS)

Although it is evident that Titan's lakes and seas are dominated by ethane, methane, nitrogen, and (in some models) propane, there is divergence on the predicted relative abundance of minor constituents such as nitriles and C-4 alkanes. Nitriles such as hydrogen cyanide and acetonitrile, which have a significant dipole moment, may have a disproportionate influence on the dielectric properties of Titan seas and may act to solvate polar molecules such as water ice. The hypothesis is offered that such salvation may act to enhance the otherwise negligible solubility of water ice bedrock in liquid hydrocarbons. Such enhanced solubility may permit solution erosion as a formation mechanism for the widespread pits and apparently karstic lakes on Titan. Prospects for testing this hypothesis in the laboratory, and with measurements on Titan, will be discussed.

Lorenz, R. D.; Lunine, J. I.; Neish, C. D.

2011-10-01

365

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

366

Conservation of salt lakes  

Microsoft Academic Search

Salt lakes have a variety of important uses and values, including especially both economic and scientific ones. These uses and values have been and are increasingly subject to degradation from a variety of impacts: diversion of inflows, pollution, agricultural practices, and introduction of exotic species are among the more important. Recognition of these impacts upon salt lakes has led to

W. D. Williams

1993-01-01

367

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

368

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

369

Lake Nyos Dam  

Microsoft Academic Search

Lake Nyos, or to be more precise, the upper 38 m of Lake Nyos, is held back by a natural dam (Figure 1) which, if it were to fail, would wreak havoc in the valleys to the north and cause a serious flood to surge down the Katsina Ala into Nigeria. Lockwood et al., [1987], who have been investigating the

S. J. Freeth

1988-01-01

370

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

371

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

372

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.

373

Lake circulation and sediment transport in Lake Myvatn  

Microsoft Academic Search

Lake circulation and sediment transport in Lake Myvatn have been calculated using AQUASEA, a numerical model developed by Vatnaskil Consulting Engineers. The goal of the modelling was to calculate changes in sediment transport within the lake due to changes in lake bathymetry caused by diatomite mining. The model uses the Galerkin finite element method and consists of a hydrodynamic flow

Snorri Pll Kjaran; Sigurdur Lrus Hlm; Eric Matthew Myer

2004-01-01

374

Spatial patterns in PCB concentrations of Lake Michigan lake trout  

USGS Publications Warehouse

Most of the PCB body burden in lake trout (Salvelinus namaycush) of the Great Lakes is from their food. PCB concentrations were determined in lake trout from three different locations in Lake Michigan during 1994-1995, and lake trout diets were analyzed at all three locations. The PCB concentrations were also determined in alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), bloater (Coregonus hoyi), slimy sculpin (Cottus cognatus), and deepwater sculpin (Myoxocephalus thompsoni), five species of prey fish eaten by lake trout in Lake Michigan, at three nearshore sites in the lake. Despite the lack of significant differences in the PCB concentrations of alewife, rainbow smelt, bloater, slimy sculpin, and deepwater sculpin from the southeastern nearshore site near Saugatuck (Michigan) compared with the corresponding PCB concentrations from the northwestern nearshore site near Sturgeon Bay (Wisconsin), PCB concentrations in lake trout at Saugatuck were significantly higher than those at Sturgeon Bay. The difference in the lake trout PCB concentrations between Saugatuck and Sturgeon Bay could be explained by diet differences. The diet of lake trout at Saugatuck was more concentrated in PCBs than the diet of Sturgeon Bay lake trout, and therefore lake trout at Saugatuck were more contaminated in PCBs that Sturgeon Bay lake trout. These findings were useful in interpreting the long-term monitoring series for contaminants in lake trout at both Saugatuck and the Wisconsin side of the lake.

Madenjian, Charles P.; DeSorcie, Timothy J.; Stedman, Ralph M.; Brown, Edward H., Jr.; Eck, Gary W.; Schmidt, Larry J.; Hesselberg, Robert J.; Chernyak, Sergei M.; Passino-Reader, Dora R.

1999-01-01

375

Lake Trout Rehabilitation in Lake Erie: A Case History  

Microsoft Academic Search

Native lake trout (Salvelinus namaycush) once thrived in the deep waters of eastern Lake Erie. The impact of nearly 70 years of unregulated exploitation and over 100 years of progressively severe cultural eutrophication resulted in the elimination of lake trout stocks by 1950. Early attempts to restore lake trout by stocking were unsuccessful in establishing a self-sustaining population. In the

Floyd C. Cornelius; Kenneth M. Muth; Roger Kenyon

1995-01-01

376

Spatial patterns in meiobenthic assemblages in intermittently open/closed coastal lakes in New South Wales, Australia  

NASA Astrophysics Data System (ADS)

Intermittently closed and open lakes and lagoons (ICOLLs) are important features of the Australian coastline. Local authorities frequently open lakes by bulldozing or dredging the mouths, in an effort to improve water-quality and to reduce the risk of flooding and these interventions provided an opportunity to examine large-scale patterns in meiobenthos in relation to isolation from the sea. Even at a coarse level of taxonomic resolution (phylum, class and order), consistent differences between assemblages of meiobenthos in different reaches of the lakes and between open and closed lakes were revealed. The abundance of meiobenthos generally decreased with increasing distance from the sea. Multivariate analyses showed that nematodes, copepods and turbellarians were characteristic of assemblages near the mouths of lakes while polychaetes and oligochaetes characterised those in more isolated areas. Furthermore, assemblages in the inner reaches of open lakes also differed from those in closed lakes. Isolated localities were less diverse and more spatially variable. Differences in meiobenthos between natural lakes and those that are artificially opened became apparent when open and closed were analysed separately. Lakes that are kept open artificially are similar to naturally open lakes despite other impacts associated with human activities. These results are considered in the context of isolation and the implications of proposed changes in the way mouths are manipulated are discussed.

Dye, A. H.; Barros, F.

2005-03-01

377

Marine Incursion: The Freshwater Herring of Lake Tanganyika Are the Product of a Marine Invasion into West Africa  

PubMed Central

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 2550MYA, 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.

Wilson, Anthony B.; Teugels, Guy G.; Meyer, Axel

2008-01-01

378

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

379

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

380

Eutrophication factors in north central Florida lakes  

Microsoft Academic Search

Nutrient loading rates were estimated for Anderson-Cue Lake in Florida. The lake was artificially spiked with phosphorus. Nutrient budgets for the lake and other lakes were compared. Nutrient sources and sinks for lakes were identified. A partial nutrient budget for Anderson-Cue lake was prepared, and the chemical composition of the lake's water was compared to rainwater. 5 tables.

P. L. Brezonik; W. H. Morgan; E. E. Shannon; H. D. Putnam

1969-01-01

381

Epidemiology of Great Lakes bald eagles.  

PubMed

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 the same chemicals were produced and released. Organochlorine chemicals appear as a unique stress on Great Lakes bald eagle populations when compared with stresses on successful populations of bald eagles continentwide. Shoreline birds bear significantly higher concentrations of these persistent toxics than inland birds. Association between contaminated prey and elevated concentrations of PCBs, DDT, and DDE in Great Lakes bald eagles are presented. A fledging ratio is used to support the hypothesis that maternal prezygotic exposure affects the viability of embryos and chicks. The ratio of the mean number of fledglings per successful territory to the mean number of fledglings per active territory, when the numerator is greater than 1.4, provides an index of exposure to contaminants by parental animals and affected offspring. When the ratio is greater than 2, parental exposure to organochlorine chemicals should be considered. The adverse effects of prezygotic exposure to the same contaminants in other animal species dependent upon Great Lakes fish, and extrabasin bald eagle populations dependent upon contaminated fish, provide consistency to the argument. The mechanism of action of the organochlorine chemicals further strengthens the causal argument indicting DDT, DDE, and PCBs. A strong association between DDT/DDE and bald eagle reproductive success is provided. However, the role of PCBs is not ruled out. Only data for total PCB concentrations in bald eagle tissue are available, and until specific PCB congeners are quantified there will be uncertainty concerning PCB's role in the Great Lakes bald eagle's lack of success. PMID:1875429

Colborn, T

1991-08-01

382

Silica dynamics in a pampean lake (Lake Chascoms, Argentina)  

Microsoft Academic Search

Silica dynamics in a pampean lake, Lake Chascoms (Chaco-Pampa plain, Argentina) is described. Pampean lakes are shallow alkaline ecosystems, with circulation pattern corresponding to polymictic lakes, due to the nearly continuous vertical mixing that promotes a high concentration of suspended particulate matter and low transparency. A silica budget was calculated in Lake Chascoms in 19992000 using a one-box model that

Patricia Miretzky; Alicia Fernndez Cirelli

2004-01-01

383

THE THREE STAGE SEA LEVEL RISE ASSESSMENT OF VULNERABILITY TO ESTUARINE SHORES (3SAVES)  

Microsoft Academic Search

Coastal sea level rise has been making headlines from Byron to Bega, as councils continue to focus on mitigating and adapting to coastal recession. However, with over 130 estuaries along the NSW coast, relatively little work has been done on how these unique and often heavily developed shorelines may respond to rising sea levels. Lake Macquarie City Council, with assistance

H Stevens

384

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

385

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

386

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

387

The origin of gas seeps and shallow gas in northern part of South China Sea  

Microsoft Academic Search

The northern part of South China Sea is of passive continental margin, which geologic units include shelf, slope and deep sea basin. There are rifting basins forming during Paleogene (or Cretaceous ?) to Quaternary developed on shelf and slope, which sediments are dominated by fluvial and lake clastic rock of Paleogene, and marine clastic rock and carbonate of Neogene -

M. Li; X. Jin

2003-01-01

388

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

389

Rising seas  

SciTech Connect

Predicting exactly how - or whether - sea level will shift in response to global warming remains a significant challenge. Scientists trained in many separate disciplines are attempting to glean answers using a variety of experimental approaches, ranging from drilling into the Antarctic ice cap to bouncing radar off the ocean from space. With such efforts, investigators have learned a great deal about how sea level has varied in the past and how it is currently changing. For example, most of these scientists agree that the ocean has been creeping upward by two millimeters a year for at least the past several decades. But determining whether a warmer climate will lead to a sudden acceleration in the rate of sea level rise remains an outstanding question. This article discusses the uncertainties, historical data, and possibilities regarding this issue.

Schneider, D.

1997-03-01

390

Boll weevil eradication: A model for sea lamprey control?  

USGS Publications Warehouse

Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying on pesticides evolved into an integrated program that included recommended farming practices and poisoned baits. However, the discovery of a boll weevil sex pheromone in 1964 allowed adoption of an ongoing program of eradication. Despite opposition over concept and cost, insecticides, pheromone traps, poisoned baits, and approved farming practices were used to eradicate boll weevils from Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama by 1999. Using the working back approach along the path of the original invasion, eradication was nearly completed by 2002 in Mississippi and eradication programs were underway in Arkansas, Tennessee, Oklahoma, Louisiana, and parts of Texas. Insecticide use for cotton production decreased 50 to 90%, and cotton yields and farm income increased an average of 78 kg/ha and $190 U.S./ha in areas where boll weevils were eradicated. For sea lampreys, integrated management uses lampricides, barriers to migration, trapping, and release of sterilized males. Although sea lamprey eradication is not currently feasible, recent research on larval and sex pheromones might provide the tools to make it possible. A successful eradication program for sea lampreys starting in Lake Superior and expanding to the lower Great Lakes would ultimately provide huge ecological and economic benefits by eliminating lampricide applications, removing barriers that block teleost fishes, and facilitating the recovery of lake trout. Should the opportunity arise, the concept of sea lamprey eradication should not be rejected out of hand. The successful boll weevil eradication program shows that sea lamprey eradication might be achievable.

Smith, J. W.; Swink, W. D.

2003-01-01

391

Yellowstone lake nanoarchaeota.  

PubMed

Considerable Nanoarchaeota novelty and diversity were encountered in Yellowstone Lake, Yellowstone National Park (YNP), where sampling targeted lake floor hydrothermal vent fluids, streamers and sediments associated with these vents, and in planktonic photic zones in three different regions of the lake. Significant homonucleotide repeats (HR) were observed in pyrosequence reads and in near full-length Sanger sequences, averaging 112 HR per 1349 bp clone and could confound diversity estimates derived from pyrosequencing, resulting in false nucleotide insertions or deletions (indels). However, Sanger sequencing of two different sets of PCR clones (110 bp, 1349 bp) demonstrated that at least some of these indels are real. The majority of the Nanoarchaeota PCR amplicons were vent associated; however, curiously, one relatively small Nanoarchaeota OTU (71 pyrosequencing reads) was only found in photic zone water samples obtained from a region of the lake furthest removed from the hydrothermal regions of the lake. Extensive pyrosequencing failed to demonstrate the presence of an Ignicoccus lineage in this lake, suggesting the Nanoarchaeota in this environment are associated with novel Archaea hosts. Defined phylogroups based on near full-length PCR clones document the significant Nanoarchaeota 16S rRNA gene diversity in this lake and firmly establish a terrestrial clade distinct from the marine Nanoarcheota as well as from other geographical locations. PMID:24062731

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

2013-09-11

392

Yellowstone Lake Nanoarchaeota  

PubMed Central

Considerable Nanoarchaeota novelty and diversity were encountered in Yellowstone Lake, Yellowstone National Park (YNP), where sampling targeted lake floor hydrothermal vent fluids, streamers and sediments associated with these vents, and in planktonic photic zones in three different regions of the lake. Significant homonucleotide repeats (HR) were observed in pyrosequence reads and in near full-length Sanger sequences, averaging 112 HR per 1349 bp clone and could confound diversity estimates derived from pyrosequencing, resulting in false nucleotide insertions or deletions (indels). However, Sanger sequencing of two different sets of PCR clones (110 bp, 1349 bp) demonstrated that at least some of these indels are real. The majority of the Nanoarchaeota PCR amplicons were vent associated; however, curiously, one relatively small Nanoarchaeota OTU (71 pyrosequencing reads) was only found in photic zone water samples obtained from a region of the lake furthest removed from the hydrothermal regions of the lake. Extensive pyrosequencing failed to demonstrate the presence of an Ignicoccus lineage in this lake, suggesting the Nanoarchaeota in this environment are associated with novel Archaea hosts. Defined phylogroups based on near full-length PCR clones document the significant Nanoarchaeota 16S rRNA gene diversity in this lake and firmly establish a terrestrial clade distinct from the marine Nanoarcheota as well as from other geographical locations.

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

2013-01-01

393

Factors of ecologic succession in oligotrophic fish communities of the Laurentian Great Lakes  

USGS Publications Warehouse

Oligotrophic fish communities of the Great Lakes have undergone successive disruptions since the mid-1800s. Major contributing factors have been intensive selective fisheries, extreme modification of the drainage, invasion of marine species, and progressive physical-chemical changes of the lake environments. Lake Ontario was the first to be affected as its basin was settled and industrialized earliest, and it was the first to be connected by canals to the mid-Atlantic where the alewife (Alosa pseudoharengus) and sea lamprey (Petromyzon marinus) which ultimately became established in the Great Lakes were abundant. Oligotrophic fish communities were successively disrupted in Lakes Erie, Huron, Michigan, and Superior as the affects of population growth, industrialization, and marine invaders spread upward in the Laurentian drainage. The degree and sequence of response of families of fish and species within families differed for each factor, but the sequence of change among families and species has been the same in response to each factor as it affected various lakes at different times. The ultimate result of the disruption of fish communities has been a reduction of productivity of oligotrophic species that ranges from extreme in Lake Ontario to moderate in Lake Superior, and which has reached a state of instability and rapid change in the upper three Great Lakes by the mid-1900s similar to the situation in Lake Ontario in the mid-1800s. Since oligotrophic species (primarily salmonines, coregonines, and deepwater cottids) are the only kinds of fish that fully occupied the entire volume of the deepwater Great Lakes (Ontario, Huron, Michigan, and Superior), the fish biomass of these lakes has been reduced as various species declined or disappeared. In Lake Erie, which is shallow, and in the shallow bays of the deep lakes, oligotrophic species were replaced by mesotrophic species, primarily percids, which have successively increased and declined. All oligotrophic species are greatly reduced or extinct in lakes Ontario and Erie, and are in various stages of decline in lakes Huron, Michigan, and Superior, from greatest to least, respectively. The percids appear to be near the end of their sequence of succession in lakes Erie, Ontario, and Huron (primarily Saginaw Bay) where only the yellow perch (Perca flavescens) remains abundant. The yellow perch appears to be on the brink of decline in Lake Erie, which has been more severely influenced by water quality change than the other lakes.

Smith, Stanford H.

1972-01-01

394

33 CFR 162.130 - Connecting waters from Lake Huron to Lake Erie; general rules.  

Code of Federal Regulations, 2010 CFR

...from Lake Huron to Lake Erie; general rules. (a) Purpose. The regulations in...connecting Lake Huron to Lake Erie (including the River Rouge) to prevent...navigation channels at the head of Lake Erie. District...

2009-07-01

395

33 CFR 162.130 - Connecting waters from Lake Huron to Lake Erie; general rules.  

Code of Federal Regulations, 2010 CFR

...from Lake Huron to Lake Erie; general rules. (a) Purpose. The regulations in...connecting Lake Huron to Lake Erie (including the River Rouge) to prevent...navigation channels at the head of Lake Erie. District...

2010-07-01

396

SIGNIFICANCE OF REGIONAL LAKE QUALITY PATTERNS TO MANAGEMENT/RESTORATION OF SPECIFIC LAKES  

EPA Science Inventory

Understanding regional lake quality patterns is important to lake management and restoration. t puts specific lake conditions into perspective, provides basis for establishing lake quality goals, assists identification of lakes most likely to benefit from protection and restorati...

397

Dating Taal Lake sediment of Philippines by using the bomb radiocarbon curve  

Microsoft Academic Search

Taal Lake is located in Batangas Province of central Philippines (14 00.1'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

H. Li; X. Xu

2008-01-01

398

Atmospheric loading of polycyclic aromatic hydrocarbons to Lake Michigan as recorded in the sediments  

Microsoft Academic Search

Five sediment cores from a north-south transect of Lake Michigan were collected using box cores deployed from the RV Lake Guardian and from a submersible (Johnson Sea Link II, RV Seaward Johnson). The sediments, analyzed for PAHs (n = 28) and ²¹°Pb to obtain accumulation rates and inventories of PAHs, were used to determine the role of the atmosphere in

Matt F. Simcik; Steven J. Eisenreich; Katherine A. Golden; Shi-Ping Liu; Elisabeth Lipiatou; Deborah L. Swackhamer; David T. Long

1996-01-01

399

Association between winter precipitation and water level fluctuations in the Great Lakes and atmospheric circulation patterns  

SciTech Connect

Atmospheric precipitation in the Great Lakes basin, as a major mediating variable between atmospheric circulation and lake levels, is analyzed relative to both. The effect of cumulative winter precipitation on lake levels varies from lake to lake and depends on both the state of the lake level itself and air temperature. For periods with a quasi-stable temperature regime, the correlation coefficient between winter precipitation and changes in lake levels from November to spring months reaches 0.8. An analysis of composite maps of mean winter 700-mb heights and sea level pressure for the years with well-above and well-below normal precipitation in the lower Great Lakes basin (Lakes Michigan-Huron, St. Clair, Erie, and Ontario) has shown that changes in precipitation are associated with the wave train structure in the lower and midtroposphere that is similar to the Pacific/North American (PNA) teleconnection pattern. During the positive phase of the PNA-like pattern, when the upper-atmospheric ridge/trough system is amplified, cyclones passing over the Great Lakes basin are frequently of Alberta (Canada) origin and carry relatively small amounts of precipitation. As a result, lake levels tend to decline. On the contrary, during the negative phase of the pattern when the atmospheric circulation is more zonal, the main storm track is oriented from the southwest to the northeast and cyclones bring enough precipitation to induce a rise in lake levels. The effect of the position of the upper-atmospheric trough over the east coast of North America on the precipitation regime in the Great Lakes basin is also demonstrated. 42 refs., 11 figs., 4 tabs.

Rodionov, S.N. [National Center for Atmospheric Research, Boulder, CO (United States)

1994-11-01

400

Declining survival of lake trout stocked during 1963-1986 in U.S. waters of Lake Superior  

USGS Publications Warehouse

The average catch per effort (CPE) values for the 1963-1982 year-classes of stocked lake trout Salvelinus namaycush caught at age 7 in gill nets and for the 1976-1986 year-classes caught at ages 2-4 in trawls declined significantly in U.S. waters of Lake Superior. The declines in CPE were not explained by reduced stocking, but rather by significant declines in survival indices of the year-classes of stocked lake trout. Increases in mortality occurred in year-classes before the fish reached ages 2-4, before they were recruited into the sport and commercial fisheries, and before they reached sizes vulnerable to sea lamprey predation. We conclude that declining abundance of stocked lake trout resulted from increased mortality, which may have been caused by competition, predation, or by a combination of these and other factors. Restoration of lake trout in Lake Superior may now depend on prudent management of naturally reproducing stocks rather than on stocking of hatchery-reared fish.

Hansen, Michael J.; Ebener, Mark P.; Schorfhaar, Richard G.; Schram, Stephen T.; Schreiner, Donald R.; Selgeby, James H.

1994-01-01

401

The storage and release of water from a large glacier-dammed lake; Russell Lake near Yakutat, Alaska, 1986  

USGS Publications Warehouse

In May 1986, the entrance to Russell Fiord, Alaska, was blocked by the advancing Hubbard Glacier, forming a 34-mile long ice-dammed lake. Runoff to the lake, mainly runoff from melting snow and glacier ice, filled the lake to an elevation of 83 feet above sea level by October 8, when the ice dam failed. The lake level rose at an average rate of 0.6 ft/day, and average daily inflow to the lake was calculated to be 16,500 cu ft/sec. After failure of the ice dam, the water level fell to the former high tide level of Russell Fiord within 24 hours. Average discharge through the breach in the ice dam during a 4-hr period of maximum water level decline is estimated to have been 3.8 million cu ft/sec. The formation and breakout of the lake is expected to be repeated as the Hubbard Glacier continues to advance, though the timing of the phenomenon cannot be predicted with certainty. (USGS)

Seitz, H. R.; Thomas, D. S.; Tomlinson, Bud

1986-01-01

402

The sediment record of Lake Ohrid (Albania/Macedonia)  

NASA Astrophysics Data System (ADS)

Lake Ohrid, a transboundary lake shared by the former Yugoslav Republic of Macedonia and the Republic of Albania is with its likely Pliocene age, considered to be the oldest existing lake in Europe. Since 2004 numerous sediment successions have been recovered from Lake Ohrid in order to investigate modern and past sedimentation patterns, to establish a tephrostratigraphic and chronological framework, and to infer past climatic and environmental changes. Frequent occurrences of well-dated tephra and cryptotephra layers as well as radiocarbon, electron spin resonance, and luminescence dating allowed the establishment of a chronological framework for the recovered sediment successions. These data revealed that the sediment successions recovered so far in part reach well back into MIS 6. Despite distinct spatial heterogeneity in sediment composition, Lake Ohrid appears to have reacted uniformly to climatic forcing on changes in catchment configuration, limnology and hydrology in the past as evidenced by contemporaneous changes in sediment composition in successions from different parts of the lake basin. The interplay of climatic forced factors has varied significantly in the course of the last glacial-interglacial cycle and led to distinctly different sediment characteristics during glacial and interglacial phases at Lake Ohrid. Beside this general pattern tied to high amplitude climate fluctuations, short-term climatic fluctuations of reduced amplitude are also recorded in the sediment successions and generally well correlated to other paleoclimate records in the Mediterranean. Initial quantitative inferences of past lake surface temperatures using the TEX86 paleothermometer revealed c. 5-6C lower temperatures in the glacial compared with the interglacial periods. The reconstructed glacial and interglacial temperatures from Lake Ohrid correspond relatively well with temperature anomalies derived from sea surface temperature reconstructions in the marine (-4C) and pollen-based temperature reconstructions in the terrestrial (-9C) vicinity. Moreover, the detection of subaquatic terrace levels implies that pronounced climate fluctuations in the past had substantial impact on the hydrological budget of the lake and led to significant lake level lowering. Dating and sedimentological analyses of sediment successions recovered from these subaquatic terrace levels point to significant lake level low stands during MIS 6, MIS 5.5, and during the last glacial inception. In order to recover longer sediment succession extending back into Pliocene times from this promising site an ICDP deep drilling campaign is envisaged and scheduled for 2011.

Vogel, H.; Wagner, B.; Sulpizio, R.; Zanchetta, G.; Schouten, S.; Leng, M. J.; Wessels, M.; Nowaczyk, N.; Hilgers, A.

2009-12-01

403

REPRODUCTION AND SURVIVAL OF THE PILEWORM NEREIS SUCCINEA IN HIGHER SALTON SEA SALINITIES  

Microsoft Academic Search

The Salton Sea is a large (200 square miles) closed salt lake in a below-sealevei depression in the Colorado Desert of southeastern California. The Sea was formed accidentally from 1905 to 1907 when flood waters of the Colorado River broke through poorly constructed i-ieadgates of an irrigation canal. Following repair of the break, ti-ic new Salton Sea evaporated to a

DEIRDRE L. KUHL

404

Coast of change: habitat loss and transformations in the Wadden Sea  

Microsoft Academic Search

In the southern North Sea, coastal people commenced with habitat conversions 1,000years ago. Partly interrupted in late medieval times by large-scale inundations of marshland, progressive embankments transformed the landward half of the amphibic transition zone between a limno-terrestric and a brackish-marine ecosystem into arable land and freshwater lakes. Sea walls rigidly separated the land from the sea. Dynamic transitional habitats

Karsten Reise

2005-01-01

405

Estimating Populations of Larval Sea Lamprey with Electrofishing Sampling Methods  

Microsoft Academic Search

Habitat classification and depletion sampling provided data for population estimates oflarval sea lamprey Petromyzon marinus in six streams tributary to the Great Lakes. At randomly chosen transects, the substrate was classified as to its suitability as habitat for larval lamprey. Depletion sampling at each transect with electroshockers produced density estimates. Population estimates were calculated from the mean density over all

Tiina A. Pajos; Jerry G. Weise

1994-01-01

406

Water input requirements of the rapidly shrinking Dead Sea  

NASA Astrophysics Data System (ADS)

The deepest point on Earth, the Dead Sea level, has been dropping alarmingly since 1978 by 0.7 m/a on average due to the accelerating water consumption in the Jordan catchment and stood in 2008 at 420 m below sea level. In this study, a terrain model of the surface area and water volume of the Dead Sea was developed from the Shuttle Radar Topography Mission data using ArcGIS. The model shows that the lake shrinks on average by 4 km2/a in area and by 0.47 km3/a in volume, amounting to a cumulative loss of 14 km3 in the last 30 years. The receding level leaves almost annually erosional terraces, recorded here for the first time by Differential Global Positioning System field surveys. The terrace altitudes were correlated among the different profiles and dated to specific years of the lake level regression, illustrating the tight correlation between the morphology of the terrace sequence and the receding lake level. Our volume-level model described here and previous work on groundwater inflow suggest that the projected Dead Sea-Red Sea channel or the Mediterranean-Dead Sea channel must have a carrying capacity of >0.9 km3/a in order to slowly re-fill the lake to its former level and to create a sustainable system of electricity generation and freshwater production by desalinization. Moreover, such a channel will maintain tourism and potash industry on both sides of the Dead Sea and reduce the natural hazard caused by the recession.

Abu Ghazleh, Shahrazad; Hartmann, Jens; Jansen, Nils; Kempe, Stephan

2009-05-01

407

Great Lakes Water Quality.  

National Technical Information Service (NTIS)

The report provides an assessment of the present water quality of the Great Lakes and their connecting channels and critically examines the data collection and analysis programs available for this evaluation. The status of remedial programs being implemen...

1974-01-01

408

Great Lakes Water Quality.  

National Technical Information Service (NTIS)

The report is the first Annual Report of the International Joint Commission pursuant to the Great Lakes Water Quality Agreement between the United States and Canada signed April 15, 1972. The Commission's report takes cognizance of significant development...

1972-01-01

409

The Lake Erie Inquiry.  

ERIC Educational Resources Information Center

|Describes experiences, or "lab puzzles," which will help students develop problem-solving skills in a laboratory setting. Outlines procedures for developing techniques, setting boundaries, and finding the number of molecules of water in Lake Erie. (RT)|

Wherley, James M.

1989-01-01

410

Limnology of Lake Minnetonka.  

National Technical Information Service (NTIS)

Fluctuations of population densities of phytoplankton in 4 basins of Lake Minnetonka in Minnesota were inferred from changes of concentrations of chlorophyll a and particulate organic carbon during the ice-fee season. Concentrations of chlorophyll a durin...

R. O. Megard

1974-01-01

411

Mormon Lake Cliffs.  

National Technical Information Service (NTIS)

An establishment of a scientific or educational natural area on the east side of Mormon Lake has been proposed. The area supports an unusual floral assemblage and may be important to vertebrates (especially migrating songbirds) as well. The cliffs include...

E. L. Smith G. L. Bender

1973-01-01

412

Great Lakes literacy principles  

Microsoft Academic Search

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

Rosanne W. Fortner; Lyndsey Manzo

2011-01-01

413

From Sea to Shining Sea  

ERIC Educational Resources Information Center

|Deep down in the depths of the sea, beautiful fish, mysterious ocean life, and unusual plants glimmer and glow in the eerie atmosphere of an ever-changing ocean. This article describes how, with this vision and a purpose in mind, three teachers pulled open classroom walls and joined forces so their second graders could create a mammoth 30 x 75"

Scott, Beverly

2005-01-01

414

A 1-Myr Record of Paleoclimates from Lake Khubsugul, Mongolia  

NASA Astrophysics Data System (ADS)

The ancient Lake Khubsugul in North Mongolia is situated at the far reach of moisture from the North Atlantic into continental Asia. It is remote from the Pacific Ocean and shielded from the Chinese Sea and the Indian Ocean by high mountains. Information on the paleoclimates in this territory is scarce and sometimes controversial. In winter of 2003, due to a joint project (Khubsugul Drilling Project or KDP) of the Siberian Branch of the Russian Academy of Sciences and the Academy of Sciences of Mongolia, a 53-m drilling core (KDP-1) of sediments of Lake Khubsugul was obtained. This article describes the first results of paleomagnetic and geochemical studies of this core, which was found to span the time interval of the last 1.05 Myr. The data suggest that global climate oscillations manifested themselves in repeated desiccation and filling of the lake due to changes in humidity.

Fedotov, Andrey; Kazansky, Aleksey Y.; Tomurhuu, Dondovyn; Matasova, Galina; Ziborova, Galina; Zheleznyakova, Tatyana; Vorobyova, Svetlana; Phedorin, Michael; Goldberg, Evgeny; Oyunchimeg, Tserentdash; Narantsetseg, Tserendash; Vologina, Elena; Yuldashev, Alexander; Kalugin, Ivan; Tomurtogoo, Onongyn; Grachev, Michael

2004-10-01

415

An ecologic and taxonomic study on phytoplankton of a shallow lake, Turkey.  

PubMed

The middle Black sea region has quite large wetlands, including lakes, rivers, ponds, marshs and large reservoirs. Lake Cernek is one of the most valuable wetlands in Kizilirmak Delta. The lake and its environment have a high biodiversity due to species richness and natural habitats. Therefore, it has been recognized as a Ramsar site. The phytoplankton of lake Cemek consisted of 104 taxa belonging to Cyanobacteria, Bacillariophyta, Chlorophyta, Cryptophyta, Dinophyta, Euglenophyta and Xanthophyta divisions. Chlorophyta (46%) and Bacillariophyta (23%) members were dominant species. These were followed by Cyanobacteria (16%) and Euglenophyta (11%) members. Chlorella, Monoraphidium, Oocystis, Pediastrum and Scenedesmus from Chlorophyceae and also Anabaena, Chroococcus and Microcystis species from Cyanophyceae sometimes made water blooms. Blue green algae constituted algal communities in the surface of the lake in summer months. Algal community and its important species were grouped in terms of bray curtis similarity index, by taking into consideration the phytoplankton dynamics and months. PMID:17929763

Tas, Beyhan; Gonulol, Arif

2007-04-01

416

TOXAPHENE STUDY OF GREAT LAKES TRIBUTARY SEDIMENTS  

EPA Science Inventory

The Product is the paper "Pulp and Paper Mills as Sources of Toxaphene to Lake Superior and Northern Lake Michigan" published in the Journal of Great Lakes Research, 25(2):383-394 International Association of Great Lakes 1999....

417

Climate implications of changing Arctic sea ice  

NASA Astrophysics Data System (ADS)

Straddling the mid-Atlantic ridge, Iceland may be best known to the world for its fiery volcanic history, violent earthquakes, and massive jkulhlaupsepisodic outbursts of sub-glacial lakes melted by underlying magma. But this poem, written by Matthias Jochumsson in 1888 and titled simply The Sea Ice [Jochumsson, 1915] illustrates why the most insidious disruption to the Icelandic people is the havoc wrought by the quiet approach of sea ice. No other natural disaster has brought such cruelty famine, and death. From Jochumsson: Where is the ocean, where is the bright, free, silvery ocean? When you [sea ice] appear, the nation and its history are extinguished; then is death, and deep, dark night

Miller, Gifford H.; Geirsdottir, slaug; Koerner, Roy M.

418

Development of sea lamprey (Petromyzon marinus) larvicides  

USGS Publications Warehouse

Larvicides are used to control sea lamprey (Petromyzon marinus) in the Great Lakes. These larvicides are useful because they are more toxic to sea lamprey than fish species found in the same habitat. The lampricides come from two classes of chemical compounds: (1) halonitrophenols, and (2) halonitrosalicylanilides. Selectivity of the larvicides appears to be based on the differences in the ability of sea lamprey larvae and fishes to detoxify and/or excrete the chemicals. Glucuronide conjugation is an important mechanism for detoxification of these larvicides by fish, and selectivity of larvicides may be due to differences in glucuronyl transferase activity between lamprey and fishes. If more detailed information were available on uptake, metabolism, excretion, and the biochemistry and physiology of lamprey as compared to fishes, it might be possible to design chemicals that would be more selective than those now in use.

Howell, John H.; Lech, John J.; Allen, John L.

1980-01-01

419

Estimation of evaporation from the Dead Sea  

NASA Astrophysics Data System (ADS)

A project to link the Dead Sea to the Red Sea via a canal is undergoing extensive study. As part of this study, a method to estimate evaporation from the Dead Sea is required as it is a hypersaline lake in which standard methods cannot be applied. Two methods based on Penman and Dalton formulae were examined. The method derived here is a modified Penman model that estimates the evaporation as a function of salinity, humidity, air temperature and wind speed. Other parameters such as water temperature are included implicitly in the model. The results obtained were verified as satisfactory agreement was achieved by comparison with previous measurements. A short-cut relationship to estimate evaporation as a function of salinity only was also derived.

Asmar, B. N.; Ergenzinger, Peter

1999-12-01

420

Availability of lake trout reproductive habitat in the Great Lakes  

USGS Publications Warehouse

A decades-long program to reestablish self-sustaining stocks of lake trout (Salvelinus namaycush) in the four lower Great Lakes produced excellent fisheries supported by stocked fish. These fish spawned widely and small numbers of their offspring were collected intermittently from Lakes Michigan, Huron, and Ontario, but no self-sustaining stocks were established. Irt this paper we address habitat sufficiency as a factor in the failure of stocked lake trout to established self-sustaining populations in the four lower Great Lakes. We present the previously unpublished results of lake trout spawning habitat surveys conducted at seven sites in the Great Lakes since 1987 and we compare them with the published results of similar surveys conducted at 24 other sites in the four lower lakes since 1981. Our evaluation indicates all but two of these sites can support the production of viable fry from spawnings by the shallow-water strains of lake trout that are stocked in the Great Lakes. However, some of the best spawning, egg, and fry habitat in the lower Great Lakes seems to be at deeper offshore sites that may be unattractive to these shallow-water strains. Thus, we suggest also stocking the lower four lakes with strains from Lake Superior that might more fully exploit the best spawning habitat at these deeper, offshore sites.

Edsall, Thomas A.; Kennedy, Gregory W.

1995-01-01

421

Sea Ice  

NSDL National Science Digital Library

In this resource, students will discover that there are notable differences between sea ice and fresh-water ice, such as density. In on segment, students learn that the first sign of freezing on the sea is an oily appearance of the water caused by the formation of needle-like crystals. The site explains the relationship between growth and the rate at which heat flows from the water and that the ice pack can alter its shape and dimension due to the movement of winds, currents, thermal expansion, and contraction of the ice. Types of ice described here include new ice, nilas, young ice, first-year ice, and old ice while the forms of ice covered include pancake ice, brash ice, ice cake, floe, and fast ice. The site also explains the meteorological and oceanographic factors that control the amount and movement of ice.

422

Microbial water quality of recreational lakes near Tbilisi, Georgia.  

PubMed

Microbial safety of recreational water is one of the major human public health issues in developing countries. Three water bodies, the Tbilisi Sea, Kumisi and Lisi lakes, in the South Caucasus region near Tbilisi, Georgia, were monitored in 2006-2009 to determine microbiological quality using standard methods. Microbial pollution indicators were determined in parallel with phytoplankton abundance and measurement of a number of physical-chemical parameters. Kumisi Lake, a brackish water body in an active agricultural area, appeared to be the most polluted, whereas the Tbilisi Sea, a freshwater reservoir was the least polluted. High values for fecal indicators in all three lakes in summer and early autumn were revealed. In our study, total enterococci counts (TEC) appeared to be a better indicator than either fecal or total coliform counts for the evaluation of fresh and brackish microbial water quality. We found significant correlation between total Vibrio counts and TEC for all three water bodies. Prevalence of somatic coliphages and V. cholerae-specific phages as additional water pollution indicator significantly correlated with abundance of the host bacteria. Particular phytoplankton groups in the lakes responded to the changes of fecal indicators; however, no correlation was observed between dominant zooplankton taxonomic groups and microbial parameters. PMID:23708580

Jaiani, Ekaterine; Kokashvili, Tamar; Mitaishvili, Nino; Elbakidze, Tinantin; Janelidze, Nino; Lashkhi, Nino; Kalandadze, Rusudan; Mikashavidze, Eteri; Natroshvili, Gulnara; Whitehouse, Chris A; Huq, Anwar; Tediashvili, Marina

2013-06-01

423

Sea World  

NSDL National Science Digital Library

Excellent resource for information and teaching activities on marine life, designed primarily for elementary level. Teachers can sign up for a monthly e-newsletter (or access archived newsletters) filled with classroom activities, current information, and special links. Also features a searchable database of Sea World education materials and information on camps, marine science careers, and Shamu TV, an award-winning series broadcast around the country via satellite and cable.

424

Contaminants in American alligator eggs from Lake Apopka, Lake Griffin, and Lake Okeechobee, Florida  

USGS Publications Warehouse

Residues of organochlorine pesticides, polychlorinated biphenyls (PCBs), and 16 elements were measured in American alligator (Alligator mississippiensis) eggs collected in 1984 from Lakes Apopka, Griffin, and Okeechobee in central and south Florida. Organochlorine pesticides were highest in eggs from Lake Apopka. None of the elements appeared to be present at harmful concentrations in eggs from any of the lakes. A larger sample of eggs was collected in 1985, but only from Lakes Griffin, a lake where eggs were relatively clean, and Apopka, where eggs were most contaminated. In 1985, hatching success of artificially incubated eggs was lower for Lake Apopka, and several organochlorine pesticides were higher than in eggs from Lake Griffin. However, within Lake Apopka, higher levels of pesticides in chemically analyzed eggs were not associated with reduced hatching success of the remaining eggs in the clutch. Therefore, it did not appear that any of the pesticides we measured were responsible for the reduced hatching of Lake Apopka eggs.

Heinz, G.H.; Percival, H.F.; Jennings, M.L.

1991-01-01

425

Evidence of Lake Trout reproduction at Lake Michigan's mid-lake reef complex  

USGS Publications Warehouse

The Mid-Lake Reef Complex (MLRC), a large area of deep (> 40 m) reefs, was a major site where indigenous lake trout (Salvelinus namaycush) in Lake Michigan aggregated during spawning. As part of an effort to restore Lake Michigan's lake trout, which were extirpated in the 1950s, yearling lake trout have been released over the MLRC since the mid-1980s and fall gill net censuses began to show large numbers of lake trout in spawning condition beginning about 1999. We report the first evidence of viable egg deposition and successful lake trout fry production at these deep reefs. Because the area's existing bathymetry and habitat were too poorly known for a priori selection of sampling sites, we used hydroacoustics to locate concentrations of large fish in the fall; fish were congregating around slopes and ridges. Subsequent observations via unmanned submersible confirmed the large, fish to be lake trout. Our technological objectives were driven by biological objectives of locating where lake trout spawn, where lake trout fry were produced, and what fishes ate lake trout eggs and fry. The unmanned submersibles were equipped with a suction sampler and electroshocker to sample eggs deposited on the reef, draw out and occasionally catch emergent fry and collect egg predators (slimy sculpin Cottus cognatus). We observed slimy sculpin to eat unusually high numbers of lake trout eggs. Our qualitative approaches are a first step toward quantitative assessments of the importance of lake trout spawning on the MLRC.

Janssen, J.; Jude, D. J.; Edsall, T. A.; Paddock, R. W.; Wattrus, N.; Toneys, M.; McKee, P.

2006-01-01

426

Satellite view of Swim Lake and nearby lakes.  

USGS Multimedia Gallery

Satellite view of Swim Lake (upper right) and nearby lakes in Polk County, Florida, surrounded by citrus groves. Courtesy Florida State University, 2008; Southwest Florida Water Management District, 2008....

2009-06-12

427

Hydrogeologic Controls on Lake Level at Mountain Lake, Virginia  

NASA Astrophysics Data System (ADS)

Mountain Lake in Giles County, Virginia has a documented history of severe natural lake-level changes involving groundwater seepage that extend over the past 4200 years. Featured in the 1986 movie Dirty Dancing, the natural lake dried up completely in September 2008 and levels have not yet recovered. A hydrogeologic investigation was undertaken in an effort to determine the factors influencing lake level changes. A daily water balance, dipole-dipole electrical resistivity surveying, well logging and chemical sampling have shed light on: 1) the influence of a fault not previously discussed in literature regarding the lake, 2) the seasonal response to precipitation of a forested first-order drainage system in fractured rock, and 3) the possibility of flow pathways related to karst features. Geologic controls on lake level were investigated using several techniques. Geophysical surveys using dipole-dipole resistivity located possible subsurface flowpaths both to and from the lake. Well logs, lineament analysis, and joint sampling were used to assess structural controls on lake hydrology. Major ions were sampled at wells, springs, streams, and the lake to evaluate possible mixing of different sources of water in the lake. Groundwater levels were monitored for correlation to lake levels, rainfall events, and possible seismic effects. The hydrology of the lake was quantified with a water balance on a daily time step. Results from the water balance indicate steady net drainage and significant recharge when vegetation is dormant, particularly during rain-on-snow melt events. The resistivity survey reveals discrete areas that represent flow pathways from the lake, as well as flowpaths to springs upgradient of the lake located in the vicinity of the fault. The survey also suggests that some flowpaths may originate outside of the topographic watershed of the lake. Chemical evidence indicates karst may underlie the lakebed. Historical data suggest that artificial intervention to mitigate seepage would be required for lake level recovery in the near future.

Roningen, J. M.; Burbey, T. J.

2011-12-01

428

Sensitivity of Lake-Enhanced Snowfall to Lake Ice Cover in the Great Lakes Region  

NASA Astrophysics Data System (ADS)

The Great Lakes exert a significant influence on the regional climate of northern United States and southern Canada, including enhancement of cold-season precipitation on and downwind of the leeward shores. Lake-enhanced snowfall occurs when air that is significantly colder than the lake's surface temperature travels over the lake. Enhanced surface sensible and latent heat fluxes relative to the surrounding land surface result in moistening and destabilization of the atmosphere and subsequent development of low-level convection. In the Great Lakes region, lake-enhanced snow occurs during late fall through early winter, with decreasing numbers of events in the late winter due to the formation of widespread lake ice. Lake ice reduces both sensible and latent heat fluxes from the surface, thereby increasing atmospheric stability and reducing lake induced convection. The degree to which ice coverage may change in future climate scenarios is largely unknown, but it is clear that any change to the fraction and duration of lake ice coverage will have an effect on lake-atmosphere interaction and the development and intensity of lake-enhanced precipitation. This study uses the NCAR Weather, Research, and Forecasting (WRF) model to examine how changes in Great Lakes fractional ice coverage affect the presence, intensity, and quantity of lake-enhanced precipitation. Sensitivity studies are used to evaluate the evolution and change in intensity of lake-enhanced snowfall in the Great Lakes region for scenarios that include (1) lake ice cover obtained from analysis fields (control simulation), (2) ice-free lakes, and (3) 100% ice coverage. Distinct lake-effect snow bands were observed in both the control and ice-free simulations, with placement of these bands further to the south and propagating further inland in the ice-free case. Melted precipitation totals increased on the order of 10 mm for ice-free lakes along the southern edges of Lake Superior, Lake Erie, and the eastern coast of Lake Ontario, while complete ice coverage extinguished nearly all lake-effect snow bands.

Wright, D. M.; Posselt, D. J.; Steiner, A. L.

2011-12-01

429

42. Peaks of Otter, Abbott Lake. View across lake to ...  

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

42. Peaks of Otter, Abbott Lake. View across lake to peaks of Outter Lodge, completed in 1964. Construction of the lake got underway in 1964. Looking east-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

430

Biogeochemical silica mass balances in Lake Michigan and Lake Superior  

Microsoft Academic Search

Silica budgets for Lake Michigan and Lake Superior differ in several respects. Mass balance calculations for both lakes agree with previous studies in that permanent burial of biogenic silica in sediments may be only about 5% of the biogenic silica produced by diatoms. Because dissolution rates are large, good estimates of permanent burial of diatoms can not be obtained indirectly

Claire L. Schelske

1985-01-01

431

Phytoplankton periodicity in a subtropical lake (Lake Kinneret, Israel)  

Microsoft Academic Search

Lake kinneret is a subtropical monomictic lake characterized by a Pyrrhophyta-Chlorophyta assemblage, supplemented by Cyanophyta in some years. Concerning their abundance and seasonal occurrence, the phytoplanktonic algae belong to two groups: algae appearing in quantity at a definite annual period and algae present throughout the year. Four stages of algal succession occur in the lake. There is a marked periodicity

Utsa Pollingher

1986-01-01

432

Swan Lake Restoration. Phase 1.  

National Technical Information Service (NTIS)

Shallowness, siltation/sedimentation, low water levels, and dense algal blooms in Swan Lake, Iowa have dropped oxygen concentrations below levels that can support fish. The recommendations are: lake deepening (dredging), reduction of shallow areas, expans...

R. Bachmann B. Lohnes D. Bonneau

1982-01-01

433

Great Lakes Monthly Hydrologic Data.  

National Technical Information Service (NTIS)

This report summarizes the monthly hydrologic data currently used by the Great Lakes Environmental Research Laboratory in their hydrologic and water resource studies of the Great Lakes. The data consist of precipitation, runoff, evaporation, connecting ch...

F. H. Quinn R. N. Kelley

1983-01-01

434

Lake-level variation in the Lahontan basin for the past 50,000 years  

USGS Publications Warehouse

Selected radiocarbon data on surficial materials from the Lahontan basin, Nevada and California, provide a chronology of lake-level variation for the past 50,000 yr. A moderate-sized lake connected three western Lahontan subbasins (the Smoke Creek-Black Rock Desert subbasin, the Pyramid Lake subbasin, and the Winnemucca Dry Lake subbasin) from about 45,000 to 16,500 yr B.P. Between 50,000 and 45,000 yr B.P., Walker Lake rose to its sill level in Adrian Valley and spilled to the Carson Desert subbasin. By 20,000 yr B.P., lake level in the western Lahontan subbasins had risen to about 1265 m above sea level, where it remained for 3500 yr. By 16,000 yr B.P., lake level in the western Lahontan subbasins had fallen to 1240 m. This recession appears synchronous with a desiccation of Walker Lake; however, whether the Walker Lake desiccation resulted from climate change or from diversion of the Walker River is not known. From about 15,000 to 13,500 yr B.P., lake level rapidly rose, so that Lake Lahontan was a single body of water by 14,000 yr B.P. The lake appears to have reached a maximum highstand altitude of 1330 m by 13,500 yr B.P., a condition that persisted until about 12,500 yr B.P., at which time lake level fell ???100 m. No data exist that indicate the level of lakes in the various subbasins between 12,000 and 10,000 yr B.P. During the Holocene, the Lahontan basin was the site of shallow lakes, with many subbasins being the site of one or more periods of desiccation. The shape of the lake-level curve for the three western subbasins indicates that past changes in the hydrologic balance (and hence climate) of the Lahontan basin were large in magnitude and took place in a rapid step-like manner. The rapid changes in lake level are hypothesized to have resulted from changes in the mean position of the jet stream, as it was forced north or south by the changing size and shape of the continental ice sheet. ?? 1987.

Benson, L. V.; Thompson, R. S.

1987-01-01

435

Mono Lake Excursion Reviewed  

NASA Astrophysics Data System (ADS)

The Mono Lake Excursion as recorded in the Mono Basin, CA, has an older part that is about negative 30 degrees inclination and about 300 degrees declination during low relative field intensity. Those paleomagnetic directions are closely followed by greater than 80 degrees positive inclination and east declination of about 100 degrees during higher relative field intensity. A path of the Virtual Geomagnetic Poles (VGPs) for the older part followed from old to young forms a large clockwise loop that reaches 35 degrees N latitude and is centered at about 35 degrees E longitude. That loop is followed by a smaller one that is counterclockwise and centered at about 70 degrees N latitude and 270 degrees E longitude (Denham & Cox, 1971; Denham, 1974; Liddicoat & Coe, 1979). The Mono Lake Excursion outside the Mono Basin in western North America is recorded as nearly the full excursion at Summer Lake, OR (Negrini et al., 1984), and as the younger portion of steep positive inclination/east declination in the Lahontan Basin, NV. The overall relative field intensity during the Mono Lake Excursion in the Lahontan Basin mirrors very closely the relative field intensity in the Mono Basin (Liddicoat, 1992, 1996; Coe & Liddicoat, 1994). Using 14C and 40Ar/39Ar dates (Kent et al., 2002) and paleoclimate and relative paleointensity records (Zimmerman et al., 2006) for the Mono Lake Excursion in the Mono Basin, it has been proposed that the Mono Lake Excursion might be older than originally believed and instead be the Laschamp Excursion at about 40,000 yrs B.P. (Guillou et al., 2004). On the contrary, we favor a younger age for the Mono Lake Excursion, about 32,000 yrs B.P., using the relative paleointensity in the Mono Basin and Lahontan Basin and 14C dates from the Lahontan Basin (Benson et al., 2002). The age of about 32,000 yrs B.P. is also in accord with the age (32,000- 34,000 yrs B.P.) reported by Channell (2006) for the Mono Lake Excursion at ODP Site 919 in the Irminger Basin in the North Atlantic Ocean, which contains as well an excursion lower in the core at about 40,000 yrs B.P. that he identifies as the Laschamp Excursion. The paths of VGPs for the Irminger Basin and the younger half of the Mono Lake Excursion in the Mono Basin are similar in that they are counterclockwise loops and nearly adjacent to each other, and quite different from the VGP path for the Laschamp Excursion.

Liddicoat, J. C.; Coe, R. S.

2007-05-01

436

Geology and geomorphology of Bear Lake Valley and upper Bear River, Utah and Idaho  

USGS Publications Warehouse

Bear Lake, on the Idaho-Utah border, lies in a fault-bounded valley through which the Bear River flows en route to the Great Salt Lake. Surficial deposits in the Bear Lake drainage basin provide a geologic context for interpretation of cores from Bear Lake deposits. In addition to groundwater discharge, Bear Lake received water and sediment from its own small drainage basin and sometimes from the Bear River and its glaciated headwaters. The lake basin interacts with the river in complex ways that are modulated by climatically induced lake-level changes, by the distribution of active Quaternary faults, and by the migration of the river across its fluvial fan north of the present lake. The upper Bear River flows northward for ???150 km from its headwaters in the northwestern Uinta Mountains, generally following the strike of regional Laramide and late Cenozoic structures. These structures likely also control the flow paths of groundwater that feeds Bear Lake, and groundwater-fed streams are the largest source of water when the lake is isolated from the Bear River. The present configuration of the Bear River with respect to Bear Lake Valley may not have been established until the late Pliocene. The absence of Uinta Range-derived quartzites in fluvial gravel on the crest of the Bear Lake Plateau east of Bear Lake suggests that the present headwaters were not part of the drainage basin in the late Tertiary. Newly mapped glacial deposits in the Bear River Range west of Bear Lake indicate several advances of valley glaciers that were probably coeval with glaciations in the Uinta Mountains. Much of the meltwater from these glaciers may have reached Bear Lake via groundwater pathways through infiltration in the karst terrain of the Bear River Range. At times during the Pleistocene, the Bear River flowed into Bear Lake and water level rose to the valley threshold at Nounan narrows. This threshold has been modified by aggradation, downcutting, and tectonics. Maximum lake levels have decreased from as high as 1830 m to 1806 m above sea level since the early Pleistocene due to episodic downcutting by the Bear River. The oldest exposed lacustrine sediments in Bear Lake Valley are probably of Pliocene age. Several high-lake phases during the early and middle Pleistocene were separated by episodes of fluvial incision. Threshold incision was not constant, however, because lake highstands of as much as 8 m above bedrock threshold level resulted from aggradation and possibly landsliding at least twice during the late-middle and late Pleistocene. Abandoned stream channels within the low-lying, fault-bounded region between Bear Lake and the modern Bear River show that Bear River progressively shifted northward during the Holocene. Several factors including faulting, location of the fluvial fan, and channel migration across the fluvial fan probably interacted to produce these changes in channel position. Late Quaternary slip rates on the east Bear Lake fault zone are estimated by using the water-level history of Bear Lake, assuming little or no displacement on dated deposits on the west side of the valley. Uplifted lacustrine deposits representing Pliocene to middle Pleistocene highstands of Bear Lake on the footwall block of the east Bear Lake fault zone provide dramatic evidence of long-term slip. Slip rates during the late Pleistocene increased from north to south along the east Bear Lake fault zone, consistent with the tectonic geomorphology. In addition, slip rates on the southern section of the fault zone have apparently decreased over the past 50 k.y. Copyright ?? 2009 The Geological Society of America.

Reheis, M. C.; Laabs, B. J. C.; Kaufman, D. S.

2009-01-01

437

Lake Nyos Dam  

NASA Astrophysics Data System (ADS)

Lake Nyos, or to be more precise, the upper 38 m of Lake Nyos, is held back by a natural dam (Figure 1) which, if it were to fail, would wreak havoc in the valleys to the north and cause a serious flood to surge down the Katsina Ala into Nigeria. Lockwood et al., [1987], who have been investigating the Lake Nyos gas disaster, which killed an estimated 1700 people in August 1986, presented a paper on the potential for disastrous failure of the Lake Nyos dam to the AGU Fall Meeting. Part of what they said was subsequently reported in New Scientist (December 10, 1987, p. 18). They have placed on record their view that the dam is only 400 years old and are reported to have stated that it is eroding away at the alarming rate of 1.5 m/yr. If their figures are correct, then surely the dam will fail within a decade or two at the most, and there is indeed cause for alarm and immediate action. However, teams from Cameroon, France, Italy, Japan , Switzerland, Britain, Nigeria, and Germany also visited Lake Nyos in the immediate aftermath of the gas disaster, and none of their reports have suggested that the dam is in itself an imminent threat.

Freeth, S. J.

438

33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.  

Code of Federal Regulations, 2010 CFR

...Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. 162.220...Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake...that portion of Lake Mohave (Colorado River) extending 4,500 feet...

2010-07-01

439

33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.  

Code of Federal Regulations, 2010 CFR

...Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. 162.220...Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake...that portion of Lake Mohave (Colorado River) extending 4,500 feet...

2009-07-01

440

Living with the Great Lakes  

NSDL National Science Digital Library

This site was developed to assist students and educators with learning about the Great Lakes. The topics discussed include, grain size, langmuir circulation, longshore current, beach drift, river plumes, lake stratification, and waves. Lesson plans can be found on the following subjects: lake levels, sediments, stream flow, and water quality. Also included is a virtual flight along the Eastern Lake Michigan Shoreline which includes topo maps, 3D maps, and photos. A directory of related links is also available.

Videtich, Patricia

441

Living With the Great Lakes  

NSDL National Science Digital Library

This site was developed to assist students and educators with learning about the Great Lakes. The links provide materials on basic earth science concepts, a set of lesson plans on the lakes, and other Great Lakes topics. Concepts covered include Langmuir circulation, longshore current and beach drift, sediments, stream flow, seasonal stratification and water quality.

442

Exploring Subglacial Antarctic Lake Environments  

Microsoft Academic Search

While subglacial lakes have been suspected, and speculated about, for more than 50 years, recent analyses of historical and new data have shown that liquid water environments are common beneath the vast Antarctic Ice Sheet. Airborne radar surveys have now documented more than 145 subglacial lakes, the largest being Lake Vostok located 4 km beneath the vast East Antarctic Ice

J. C. Priscu; M. C. Kennicutt III; R. E. Bell; S. A. Bulat; J. C. Ellis-Evans; V. V. Lukin; J.-R. Petit; R. D. Powell; M. J. Siegert; I. Tabacco

2005-01-01

443

Great Lakes: Great Decisions (A)  

Microsoft Academic Search

One of the few remaining producers of lead additives must decide whether to continue producing them for use abroad. Banned in the United States, lead additives were still legal in developing nations. Ellie Shannon, the division manager overseeing bromine production for the Indiana-based Great Lakes Chemical Corporation (Great Lakes), must advise Great Lakes' directors on whether the company should 1)

R. Freeman; Andrew Wicks; Patricia Werhane; Jenny Mead

444

Ecological study of Ghodaghodi lake  

Microsoft Academic Search

Wetlands comprise 5% of world's total land areas of Nepal. The present study Ghodaghodi Lake in the Far-West Nepal Terai manifested the physicochemical contamination in the lake. All the parameters were within the WHO guideline values except for Phosphate and Dissolved Oxygen. Water depth varies form 1-4 m. High phosphate level suggested that the lake is hypertrophic. Dissolved oxygen was

J. Diwakar; S Barjracharya; U. R. Yadav

2009-01-01

445

Sea Cucumbers  

NSDL National Science Digital Library

What reef animal comes in a rainbow of crazy colors, can throw out its innards to immobilize predators, then creep away and regrow a brand-new stomach? Its the sea cucumber, prized as a gastronomic delight by some cultures and beginning to yield some of its secrets to scientists. Follow host Ari Daniel Shapiro from a Chinatown market to the reefs of Fiji to learn more about this amazing creature. Also included is a Learn More section that provides background information on the scientists recorded in the podcast, lessons, images, and cool facts.

2009-01-01

446

Titan Mare Explorer (TiME) : A Discovery Mission to Titan's Hydrocarbon Seas  

NASA Astrophysics Data System (ADS)

The discovery of lakes in Titan's high latitudes confirmed the expectation that liquid hydrocarbons exist on the surface of the haze-shrouded moon. The lakes fill through drainage of subsurface runoff and/or intersection with the subsurface alkanofer, providing the first evidence for an active condensable-liquid hydrological cycle on another planetary body. The unique nature of Titan's methane cycle, along with the prebiotic chemistry and implications for habitability of Titan's lakes, make the lakes of the highest scientific priority for in situ investigation. The Titan Mare Explorer mission is an ASRG (Advanced Stirling Radioisotope Generator)-powered mission to a lake on Titan. The mission would be the first exploration of a planetary sea beyond Earth, would demonstrate the ASRG both in deep space and a non-terrestrial atmosphere environment, and pioneer low-cost outer planet missions. The scientific objectives of the mission are to: determine the chemistry of a Titan lake to constrain Titan's methane cycle; determine the depth of a Titan lake; characterize physical properties of liquids; determine how the local meteorology over the lakes ties to the global cycling of methane; and analyze the morphology of lake surfaces, and if possible, shorelines, in order to constrain the kinetics of liquids and better understand the origin and evolution of Titan lakes. The focused scientific goals, combined with the new ASRG technology and the unique mission design, allows for a new class of mission at much lower cost than previous outer planet exploration has required.

Lorenz, Ralph D.; Stofan, Ellen; T. H. E. Time Team

2010-05-01

447

Mammals of the Sea.  

ERIC Educational Resources Information Center

|Presents information on sea mammals, including definitions and characteristics of cetaceans, pinnipeds, and sirenians. Contains descriptions of the teaching activities "Whale Music,""Draw A Whale to Scale,""Adopt a Sea Mammal," and "Sea Mammal Sleuths." (TW)|

Naturescope, 1986

1986-01-01

448

Tracking Sea Otters  

USGS Multimedia Gallery

USGS sea otter researcher Tim Tinker drives the boat on an expedition to track and observe sea o